Paola Spriano

Physicians who treat patients are potentially exposed to two opposing psychological processes: A positive feeling related to the experience of helping someone in need and, on the other hand, the adverse experience of seeing someone’s suffering and being frustrated about their inability to help. The ability to share the feelings of others is often referred to as empathy, while the ability to care for and show interest in others is the key aspect of compassion. Empathy makes it possible to share the positive and negative feelings of others in the same way: We can therefore feel happy when we indirectly share others’ joy and sad when we indirectly share others’ suffering.

Empathy in healthcare professionals is associated with patient satisfaction, diagnostic accuracy, adherence to treatment recommendations, clinical outcomes, clinical expertise, and physician retention. However, evidence indicates a tendency for empathy to decline during physicians’ training and specialization.
 

Estimating Empathy

Empathy studies are primarily based on observational data that include physician self-assessment or patient-perceived empathy. External evaluation of empathy by the recipient or observer is not the dominant approach, and a systematic review of the topic showed that, in 331 of the 470 studies examined (70.4%), individuals self-reported their level of empathy. The self-assessment system, particularly for doctors, is more likely to measure the doctor’s attitudes about empathy than empathy itself. The lack of correlation between physician and patient empathy assessments made it clear that patients cannot be disregarded when assessing physician empathy.

Consultation and Relational Empathy (CARE) is the primary assessment tool available to patients to measure physician empathy. It is a reliable and consistent system, particularly in primary care scenarios.

The CARE measure captures even small nuances of patient interactions with the physician and has been confirmed as a valuable tool in assessing the relational components of empathy.
 

Doctor-Patient Relationship

Communication with the physician is generally considered an important element of chronic pain care because it affects patient engagement and decision-making. A collaborative approach involving the patient and clinician in clinical decisions was associated with adherence to pain treatment and improved outcomes among patients with chronic lower back pain. The study conducted in a primary care setting of 1352 participants showed findings regarding physician empathy that did not necessarily involve a therapeutic alliance with the patient based on collaborative communication or expectation of a therapeutic effect of pharmacotherapy. Physician empathy remained the strongest factor associated with patient satisfaction, even after considering various potential confounders, including communication with the physician. In addition, ongoing empathy, especially when reported by patients with a long-term relationship with the physician, supported the hypothesis of a possible lasting effect on patient satisfaction.

Treating Chronic Pain

Empathy is an aspect of the doctor-patient relationship that may be particularly important in patients with chronic pain. A cohort study of 1470 patients with chronic low back pain analyzed whether and how it correlated with chronic pain outcomes. Patients reported their physician’s empathy at the time of enrollment using the CARE measure, which included 10 items on physician’s empathy characteristics during meetings. Physicians whose scores were 30 or higher (ie, rated as good, very good, or excellent in most items) were classified as very empathetic physicians (VEPs), while those whose scores were 29 or lower (ie, rated as poor or passable in most items) were classified as slightly empathetic physicians (SEPs).

Pain intensity was measured with a numerical rating scale (0-10) for the typical pain level within 7 days before each encounter. The long-term stability of CARE scores was assessed in patients who maintained the same physician for more than 24 months. The study showed the following results:

• The CARE score was inversely associated with pain intensity (P < .001).
• Pain intensity was lower in patients in the VEP group than those in the SEP group (6.3 vs 6.7; P < .001).
• The likelihood of having a more empathetic physician generally increased with the decrease in the cut point of the CARE score for greater or less empathy of the physician.
• The extent of the physician’s empathy effects exceeded that reported for nonpharmacological treatments, current opioid use, and lumbar spine surgery.
• The effects of the interaction of empathy with time tended to favor the VEP group with regard to pain but were not statistically significant.

Empathy is an essential aspect of the patient-physician relationship (particularly in delivering care), and these findings demonstrate its relevance in pain therapy. Empathy has high therapeutic value, compared with many pain treatments that are often recommended in clinical practice.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Physicians who treat patients are potentially exposed to two opposing psychological processes: A positive feeling related to the experience of helping someone in need and, on the other hand, the adverse experience of seeing someone’s suffering and being frustrated about their inability to help. The ability to share the feelings of others is often referred to as empathy, while the ability to care for and show interest in others is the key aspect of compassion. Empathy makes it possible to share the positive and negative feelings of others in the same way: We can therefore feel happy when we indirectly share others’ joy and sad when we indirectly share others’ suffering.

Empathy in healthcare professionals is associated with patient satisfaction, diagnostic accuracy, adherence to treatment recommendations, clinical outcomes, clinical expertise, and physician retention. However, evidence indicates a tendency for empathy to decline during physicians’ training and specialization.
 

Estimating Empathy

Empathy studies are primarily based on observational data that include physician self-assessment or patient-perceived empathy. External evaluation of empathy by the recipient or observer is not the dominant approach, and a systematic review of the topic showed that, in 331 of the 470 studies examined (70.4%), individuals self-reported their level of empathy. The self-assessment system, particularly for doctors, is more likely to measure the doctor’s attitudes about empathy than empathy itself. The lack of correlation between physician and patient empathy assessments made it clear that patients cannot be disregarded when assessing physician empathy.

Consultation and Relational Empathy (CARE) is the primary assessment tool available to patients to measure physician empathy. It is a reliable and consistent system, particularly in primary care scenarios.

The CARE measure captures even small nuances of patient interactions with the physician and has been confirmed as a valuable tool in assessing the relational components of empathy.
 

Doctor-Patient Relationship

Communication with the physician is generally considered an important element of chronic pain care because it affects patient engagement and decision-making. A collaborative approach involving the patient and clinician in clinical decisions was associated with adherence to pain treatment and improved outcomes among patients with chronic lower back pain. The study conducted in a primary care setting of 1352 participants showed findings regarding physician empathy that did not necessarily involve a therapeutic alliance with the patient based on collaborative communication or expectation of a therapeutic effect of pharmacotherapy. Physician empathy remained the strongest factor associated with patient satisfaction, even after considering various potential confounders, including communication with the physician. In addition, ongoing empathy, especially when reported by patients with a long-term relationship with the physician, supported the hypothesis of a possible lasting effect on patient satisfaction.

Treating Chronic Pain

Empathy is an aspect of the doctor-patient relationship that may be particularly important in patients with chronic pain. A cohort study of 1470 patients with chronic low back pain analyzed whether and how it correlated with chronic pain outcomes. Patients reported their physician’s empathy at the time of enrollment using the CARE measure, which included 10 items on physician’s empathy characteristics during meetings. Physicians whose scores were 30 or higher (ie, rated as good, very good, or excellent in most items) were classified as very empathetic physicians (VEPs), while those whose scores were 29 or lower (ie, rated as poor or passable in most items) were classified as slightly empathetic physicians (SEPs).

Pain intensity was measured with a numerical rating scale (0-10) for the typical pain level within 7 days before each encounter. The long-term stability of CARE scores was assessed in patients who maintained the same physician for more than 24 months. The study showed the following results:

• The CARE score was inversely associated with pain intensity (P < .001).
• Pain intensity was lower in patients in the VEP group than those in the SEP group (6.3 vs 6.7; P < .001).
• The likelihood of having a more empathetic physician generally increased with the decrease in the cut point of the CARE score for greater or less empathy of the physician.
• The extent of the physician’s empathy effects exceeded that reported for nonpharmacological treatments, current opioid use, and lumbar spine surgery.
• The effects of the interaction of empathy with time tended to favor the VEP group with regard to pain but were not statistically significant.

Empathy is an essential aspect of the patient-physician relationship (particularly in delivering care), and these findings demonstrate its relevance in pain therapy. Empathy has high therapeutic value, compared with many pain treatments that are often recommended in clinical practice.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Physicians who treat patients are potentially exposed to two opposing psychological processes: A positive feeling related to the experience of helping someone in need and, on the other hand, the adverse experience of seeing someone’s suffering and being frustrated about their inability to help. The ability to share the feelings of others is often referred to as empathy, while the ability to care for and show interest in others is the key aspect of compassion. Empathy makes it possible to share the positive and negative feelings of others in the same way: We can therefore feel happy when we indirectly share others’ joy and sad when we indirectly share others’ suffering.

Empathy in healthcare professionals is associated with patient satisfaction, diagnostic accuracy, adherence to treatment recommendations, clinical outcomes, clinical expertise, and physician retention. However, evidence indicates a tendency for empathy to decline during physicians’ training and specialization.
 

Estimating Empathy

Empathy studies are primarily based on observational data that include physician self-assessment or patient-perceived empathy. External evaluation of empathy by the recipient or observer is not the dominant approach, and a systematic review of the topic showed that, in 331 of the 470 studies examined (70.4%), individuals self-reported their level of empathy. The self-assessment system, particularly for doctors, is more likely to measure the doctor’s attitudes about empathy than empathy itself. The lack of correlation between physician and patient empathy assessments made it clear that patients cannot be disregarded when assessing physician empathy.

Consultation and Relational Empathy (CARE) is the primary assessment tool available to patients to measure physician empathy. It is a reliable and consistent system, particularly in primary care scenarios.

The CARE measure captures even small nuances of patient interactions with the physician and has been confirmed as a valuable tool in assessing the relational components of empathy.
 

Doctor-Patient Relationship

Communication with the physician is generally considered an important element of chronic pain care because it affects patient engagement and decision-making. A collaborative approach involving the patient and clinician in clinical decisions was associated with adherence to pain treatment and improved outcomes among patients with chronic lower back pain. The study conducted in a primary care setting of 1352 participants showed findings regarding physician empathy that did not necessarily involve a therapeutic alliance with the patient based on collaborative communication or expectation of a therapeutic effect of pharmacotherapy. Physician empathy remained the strongest factor associated with patient satisfaction, even after considering various potential confounders, including communication with the physician. In addition, ongoing empathy, especially when reported by patients with a long-term relationship with the physician, supported the hypothesis of a possible lasting effect on patient satisfaction.

Treating Chronic Pain

Empathy is an aspect of the doctor-patient relationship that may be particularly important in patients with chronic pain. A cohort study of 1470 patients with chronic low back pain analyzed whether and how it correlated with chronic pain outcomes. Patients reported their physician’s empathy at the time of enrollment using the CARE measure, which included 10 items on physician’s empathy characteristics during meetings. Physicians whose scores were 30 or higher (ie, rated as good, very good, or excellent in most items) were classified as very empathetic physicians (VEPs), while those whose scores were 29 or lower (ie, rated as poor or passable in most items) were classified as slightly empathetic physicians (SEPs).

Pain intensity was measured with a numerical rating scale (0-10) for the typical pain level within 7 days before each encounter. The long-term stability of CARE scores was assessed in patients who maintained the same physician for more than 24 months. The study showed the following results:

• The CARE score was inversely associated with pain intensity (P < .001).
• Pain intensity was lower in patients in the VEP group than those in the SEP group (6.3 vs 6.7; P < .001).
• The likelihood of having a more empathetic physician generally increased with the decrease in the cut point of the CARE score for greater or less empathy of the physician.
• The extent of the physician’s empathy effects exceeded that reported for nonpharmacological treatments, current opioid use, and lumbar spine surgery.
• The effects of the interaction of empathy with time tended to favor the VEP group with regard to pain but were not statistically significant.

Empathy is an essential aspect of the patient-physician relationship (particularly in delivering care), and these findings demonstrate its relevance in pain therapy. Empathy has high therapeutic value, compared with many pain treatments that are often recommended in clinical practice.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Coffee and tea are among the plants that are highest in caffeine. Their use as beverages makes caffeine the most consumed psychoactive agent in the world. Coffee is commonly used to increase alertness and work productivity. Synthetic caffeine is added to soft drinks, energy drinks, and products intended to reduce fatigue or promote weight loss.

The caffeine content varies with the type of drink: It is high in coffee, energy drinks, and caffeine tablets; intermediate in tea; and low in soft drinks. Coffee is the predominant source of the caffeine ingested by adults. The evidence for caffeine’s effects on people is ambiguous, and some risks and benefits deserve special attention because of the impact they may have on our health.
 

Characteristics of Caffeine

Caffeine is a methylxanthine that is completely absorbed 45 minutes after ingestion, peaking between 15 minutes and 2 hours. The half-life of caffeine varies according to age. In adults, it is 2.5-4.5 hours; in newborns, 80 hours; in children older than 6 months, it remains stable over time with respect to weight. Smoking accelerates caffeine metabolism by reducing the half-life by 50%. Oral contraceptives, however, double caffeine’s half-life. Caffeine metabolism is reduced during pregnancy (it is greater in the first trimester), with a half-life of more than 15 hours. Caffeine clearance can be slowed by several classes of drugs (eg, quinolones, cardiovascular drugs, bronchodilators, and antidepressants) that increase its half-life because they are metabolized by the same liver enzymes.

Caffeine passes the blood-brain barrier and, having an adenosine-like structure, inhibits adenosine’s effects by binding to adenosine receptors. In the brain, caffeine reduces fatigue, increases alertness, reduces reaction times, may reduce the risk for depression, and increases the effectiveness of nonsteroidal anti-inflammatory drugs in treating headaches and other types of pain.
 

Caffeine and Chronic Diseases

The evidence available on the relationship between caffeine and health has several methodological limitations. Observations of the acute effects of caffeine may not reflect long-term effects because tolerance to caffeine’s effects may develop over time. Smoking and unhealthy lifestyles are confounding factors in epidemiological studies of caffeine intake. In addition, the estimate of the amount and frequency of caffeine intake is often inaccurate because it is mainly based on self-assessment systems. Finally, prospective studies of caffeine consumption are mainly based on coffee and tea consumption, but it is unclear how much the observed outcomes can be translated to intake of other beverages such as energy drinks.

Considering the very high prevalence of arterial hypertension worldwide (31.1% of adults), many questions have been raised about the influence of coffee consumption on blood pressure (BP) and the risk for arterial hypertension. Administration of 200-300 mg caffeine is shown to induce a mean increase of 8.1 mm Hg systolic BP and 5.7 mm Hg diastolic BP. The increase is observed in the first hour after caffeine intake and lasts no longer than 3 hours.

Yet, the moderate and usual consumption of coffee does not increase, but may even reduce, the risk of developing high BP. In contrast, occasional coffee consumption can have hypertensive effects, and moderate and usual consumption in patients with high BP does not appear to increase the risk for uncontrolled BP and can reduce the risk for death from any cause. The inverse association between coffee consumption and hypertension risk was confirmed in a review and meta-analysis of cross-sectional and cohort studies.

With respect to lipid metabolism, cholesterol levels may increase after caffeine consumption because of cafestol. Concentrations of cafestol are high in unfiltered coffee, intermediate in espresso and moka pot coffee, and negligible in instant or filtered coffee. Studies on the impact of coffee on lipid levels have led to inconsistent results, however. Data have shown that people who drink more coffee have higher triglycerides, total cholesterol, and low-density lipoprotein cholesterol (LDL-C) levels. Other data have shown that caffeine promotes LDL receptor expression and clearance of LDL cholesterol.

Experimental and cohort studies have not shown an association between coffee consumption and atrial fibrillation (AF). In fact, evidence suggests that coffee consumption tends to reduce the risk for AF in a dose-response relationship. Similarly, coffee consumption is not associated with increased risk for cardiovascular events in the general population or among patients with a history of hypertension, diabetes, or cardiovascular disease.

The Coffee and Real-Time Atrial and Ventricular Ectopy study evaluated the acute effects of coffee consumption on cardiac ectopy using wearable sensors with continuous recording. It did not demonstrate any increase in daily premature atrial contractions with coffee consumption, compared with abstaining from caffeine. 

In patients with type 2 diabetes, a study performed in Japan showed that coffee consumption was associated with reduced all-cause mortality. The results suggested a dose-response relationship, and drinking coffee and green tea appeared to reduce mortality risk further. The results were not generalizable, however, because of the study population’s ethnic homogeneity.
 

Dose and Toxicity

Caffeine at high doses (> 400 mg daily) and in susceptible patients can induce anxiety, but the effects of caffeine on sleep and anxiety can differ from patient to patient. This variation reflects differences in caffeine metabolism rate and adenosine receptor gene variants.

High caffeine intake can stimulate diuresis, but without causing damaging effects on hydration when taking moderate doses of caffeine (≤ 400 mg daily) for long periods. Stopping caffeine suddenly, in a regular consumer, can lead to withdrawal symptoms such as headache, asthenia, decreased attention, depressed mood, and flu-like symptoms.

The toxic effects of caffeine occur with intake > 1.2 g. A dose of 10-14 g is considered fatal. Caffeine overdose is rare when considering traditional methods of intake (coffee and tea) because 70-100 cups of coffee should be sufficient for caffeine poisoning. Severe events can occur following the use of caffeine tablets or as energy drinks for the following reasons:

• The episodic consumption of caffeine does not allow for tolerance to develop.
• Young people are more vulnerable to the effects of caffeine.
• Caffeine has a synergistic effect in combination with other components in energy drinks.
• Taking caffeine in combination with alcohol or intense exertion causes serious, even fatal, outcomes.

Products Containing Caffeine

Evidence supports the relationship between high consumption (approximately 1 L) of energy drinks with a caffeine content of 320 mg and short-term cardiovascular adverse events, such as increased BP, QT-segment prolongation corrected for heart rate, and palpitations. These tests prompt the recommendation to avoid consuming these beverages in high quantities and in association with alcohol.

Weight loss products generally contain caffeine coupled with herbal extracts that are expected to improve fat metabolism, lipolysis, and oxidation. These products, because of their easy availability, presumed benefits, and high caffeine concentration, may be more susceptible to misuse because they can be taken in larger portions than recommended. The combination of multiple ingredients, concentrated amounts of caffeine, and excessive consumption increases the likelihood of adverse effects.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Coffee and tea are among the plants that are highest in caffeine. Their use as beverages makes caffeine the most consumed psychoactive agent in the world. Coffee is commonly used to increase alertness and work productivity. Synthetic caffeine is added to soft drinks, energy drinks, and products intended to reduce fatigue or promote weight loss.

The caffeine content varies with the type of drink: It is high in coffee, energy drinks, and caffeine tablets; intermediate in tea; and low in soft drinks. Coffee is the predominant source of the caffeine ingested by adults. The evidence for caffeine’s effects on people is ambiguous, and some risks and benefits deserve special attention because of the impact they may have on our health.
 

Characteristics of Caffeine

Caffeine is a methylxanthine that is completely absorbed 45 minutes after ingestion, peaking between 15 minutes and 2 hours. The half-life of caffeine varies according to age. In adults, it is 2.5-4.5 hours; in newborns, 80 hours; in children older than 6 months, it remains stable over time with respect to weight. Smoking accelerates caffeine metabolism by reducing the half-life by 50%. Oral contraceptives, however, double caffeine’s half-life. Caffeine metabolism is reduced during pregnancy (it is greater in the first trimester), with a half-life of more than 15 hours. Caffeine clearance can be slowed by several classes of drugs (eg, quinolones, cardiovascular drugs, bronchodilators, and antidepressants) that increase its half-life because they are metabolized by the same liver enzymes.

Caffeine passes the blood-brain barrier and, having an adenosine-like structure, inhibits adenosine’s effects by binding to adenosine receptors. In the brain, caffeine reduces fatigue, increases alertness, reduces reaction times, may reduce the risk for depression, and increases the effectiveness of nonsteroidal anti-inflammatory drugs in treating headaches and other types of pain.
 

Caffeine and Chronic Diseases

The evidence available on the relationship between caffeine and health has several methodological limitations. Observations of the acute effects of caffeine may not reflect long-term effects because tolerance to caffeine’s effects may develop over time. Smoking and unhealthy lifestyles are confounding factors in epidemiological studies of caffeine intake. In addition, the estimate of the amount and frequency of caffeine intake is often inaccurate because it is mainly based on self-assessment systems. Finally, prospective studies of caffeine consumption are mainly based on coffee and tea consumption, but it is unclear how much the observed outcomes can be translated to intake of other beverages such as energy drinks.

Considering the very high prevalence of arterial hypertension worldwide (31.1% of adults), many questions have been raised about the influence of coffee consumption on blood pressure (BP) and the risk for arterial hypertension. Administration of 200-300 mg caffeine is shown to induce a mean increase of 8.1 mm Hg systolic BP and 5.7 mm Hg diastolic BP. The increase is observed in the first hour after caffeine intake and lasts no longer than 3 hours.

Yet, the moderate and usual consumption of coffee does not increase, but may even reduce, the risk of developing high BP. In contrast, occasional coffee consumption can have hypertensive effects, and moderate and usual consumption in patients with high BP does not appear to increase the risk for uncontrolled BP and can reduce the risk for death from any cause. The inverse association between coffee consumption and hypertension risk was confirmed in a review and meta-analysis of cross-sectional and cohort studies.

With respect to lipid metabolism, cholesterol levels may increase after caffeine consumption because of cafestol. Concentrations of cafestol are high in unfiltered coffee, intermediate in espresso and moka pot coffee, and negligible in instant or filtered coffee. Studies on the impact of coffee on lipid levels have led to inconsistent results, however. Data have shown that people who drink more coffee have higher triglycerides, total cholesterol, and low-density lipoprotein cholesterol (LDL-C) levels. Other data have shown that caffeine promotes LDL receptor expression and clearance of LDL cholesterol.

Experimental and cohort studies have not shown an association between coffee consumption and atrial fibrillation (AF). In fact, evidence suggests that coffee consumption tends to reduce the risk for AF in a dose-response relationship. Similarly, coffee consumption is not associated with increased risk for cardiovascular events in the general population or among patients with a history of hypertension, diabetes, or cardiovascular disease.

The Coffee and Real-Time Atrial and Ventricular Ectopy study evaluated the acute effects of coffee consumption on cardiac ectopy using wearable sensors with continuous recording. It did not demonstrate any increase in daily premature atrial contractions with coffee consumption, compared with abstaining from caffeine. 

In patients with type 2 diabetes, a study performed in Japan showed that coffee consumption was associated with reduced all-cause mortality. The results suggested a dose-response relationship, and drinking coffee and green tea appeared to reduce mortality risk further. The results were not generalizable, however, because of the study population’s ethnic homogeneity.
 

Dose and Toxicity

Caffeine at high doses (> 400 mg daily) and in susceptible patients can induce anxiety, but the effects of caffeine on sleep and anxiety can differ from patient to patient. This variation reflects differences in caffeine metabolism rate and adenosine receptor gene variants.

High caffeine intake can stimulate diuresis, but without causing damaging effects on hydration when taking moderate doses of caffeine (≤ 400 mg daily) for long periods. Stopping caffeine suddenly, in a regular consumer, can lead to withdrawal symptoms such as headache, asthenia, decreased attention, depressed mood, and flu-like symptoms.

The toxic effects of caffeine occur with intake > 1.2 g. A dose of 10-14 g is considered fatal. Caffeine overdose is rare when considering traditional methods of intake (coffee and tea) because 70-100 cups of coffee should be sufficient for caffeine poisoning. Severe events can occur following the use of caffeine tablets or as energy drinks for the following reasons:

• The episodic consumption of caffeine does not allow for tolerance to develop.
• Young people are more vulnerable to the effects of caffeine.
• Caffeine has a synergistic effect in combination with other components in energy drinks.
• Taking caffeine in combination with alcohol or intense exertion causes serious, even fatal, outcomes.

Products Containing Caffeine

Evidence supports the relationship between high consumption (approximately 1 L) of energy drinks with a caffeine content of 320 mg and short-term cardiovascular adverse events, such as increased BP, QT-segment prolongation corrected for heart rate, and palpitations. These tests prompt the recommendation to avoid consuming these beverages in high quantities and in association with alcohol.

Weight loss products generally contain caffeine coupled with herbal extracts that are expected to improve fat metabolism, lipolysis, and oxidation. These products, because of their easy availability, presumed benefits, and high caffeine concentration, may be more susceptible to misuse because they can be taken in larger portions than recommended. The combination of multiple ingredients, concentrated amounts of caffeine, and excessive consumption increases the likelihood of adverse effects.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Coffee and tea are among the plants that are highest in caffeine. Their use as beverages makes caffeine the most consumed psychoactive agent in the world. Coffee is commonly used to increase alertness and work productivity. Synthetic caffeine is added to soft drinks, energy drinks, and products intended to reduce fatigue or promote weight loss.

The caffeine content varies with the type of drink: It is high in coffee, energy drinks, and caffeine tablets; intermediate in tea; and low in soft drinks. Coffee is the predominant source of the caffeine ingested by adults. The evidence for caffeine’s effects on people is ambiguous, and some risks and benefits deserve special attention because of the impact they may have on our health.
 

Characteristics of Caffeine

Caffeine is a methylxanthine that is completely absorbed 45 minutes after ingestion, peaking between 15 minutes and 2 hours. The half-life of caffeine varies according to age. In adults, it is 2.5-4.5 hours; in newborns, 80 hours; in children older than 6 months, it remains stable over time with respect to weight. Smoking accelerates caffeine metabolism by reducing the half-life by 50%. Oral contraceptives, however, double caffeine’s half-life. Caffeine metabolism is reduced during pregnancy (it is greater in the first trimester), with a half-life of more than 15 hours. Caffeine clearance can be slowed by several classes of drugs (eg, quinolones, cardiovascular drugs, bronchodilators, and antidepressants) that increase its half-life because they are metabolized by the same liver enzymes.

Caffeine passes the blood-brain barrier and, having an adenosine-like structure, inhibits adenosine’s effects by binding to adenosine receptors. In the brain, caffeine reduces fatigue, increases alertness, reduces reaction times, may reduce the risk for depression, and increases the effectiveness of nonsteroidal anti-inflammatory drugs in treating headaches and other types of pain.
 

Caffeine and Chronic Diseases

The evidence available on the relationship between caffeine and health has several methodological limitations. Observations of the acute effects of caffeine may not reflect long-term effects because tolerance to caffeine’s effects may develop over time. Smoking and unhealthy lifestyles are confounding factors in epidemiological studies of caffeine intake. In addition, the estimate of the amount and frequency of caffeine intake is often inaccurate because it is mainly based on self-assessment systems. Finally, prospective studies of caffeine consumption are mainly based on coffee and tea consumption, but it is unclear how much the observed outcomes can be translated to intake of other beverages such as energy drinks.

Considering the very high prevalence of arterial hypertension worldwide (31.1% of adults), many questions have been raised about the influence of coffee consumption on blood pressure (BP) and the risk for arterial hypertension. Administration of 200-300 mg caffeine is shown to induce a mean increase of 8.1 mm Hg systolic BP and 5.7 mm Hg diastolic BP. The increase is observed in the first hour after caffeine intake and lasts no longer than 3 hours.

Yet, the moderate and usual consumption of coffee does not increase, but may even reduce, the risk of developing high BP. In contrast, occasional coffee consumption can have hypertensive effects, and moderate and usual consumption in patients with high BP does not appear to increase the risk for uncontrolled BP and can reduce the risk for death from any cause. The inverse association between coffee consumption and hypertension risk was confirmed in a review and meta-analysis of cross-sectional and cohort studies.

With respect to lipid metabolism, cholesterol levels may increase after caffeine consumption because of cafestol. Concentrations of cafestol are high in unfiltered coffee, intermediate in espresso and moka pot coffee, and negligible in instant or filtered coffee. Studies on the impact of coffee on lipid levels have led to inconsistent results, however. Data have shown that people who drink more coffee have higher triglycerides, total cholesterol, and low-density lipoprotein cholesterol (LDL-C) levels. Other data have shown that caffeine promotes LDL receptor expression and clearance of LDL cholesterol.

Experimental and cohort studies have not shown an association between coffee consumption and atrial fibrillation (AF). In fact, evidence suggests that coffee consumption tends to reduce the risk for AF in a dose-response relationship. Similarly, coffee consumption is not associated with increased risk for cardiovascular events in the general population or among patients with a history of hypertension, diabetes, or cardiovascular disease.

The Coffee and Real-Time Atrial and Ventricular Ectopy study evaluated the acute effects of coffee consumption on cardiac ectopy using wearable sensors with continuous recording. It did not demonstrate any increase in daily premature atrial contractions with coffee consumption, compared with abstaining from caffeine. 

In patients with type 2 diabetes, a study performed in Japan showed that coffee consumption was associated with reduced all-cause mortality. The results suggested a dose-response relationship, and drinking coffee and green tea appeared to reduce mortality risk further. The results were not generalizable, however, because of the study population’s ethnic homogeneity.
 

Dose and Toxicity

Caffeine at high doses (> 400 mg daily) and in susceptible patients can induce anxiety, but the effects of caffeine on sleep and anxiety can differ from patient to patient. This variation reflects differences in caffeine metabolism rate and adenosine receptor gene variants.

High caffeine intake can stimulate diuresis, but without causing damaging effects on hydration when taking moderate doses of caffeine (≤ 400 mg daily) for long periods. Stopping caffeine suddenly, in a regular consumer, can lead to withdrawal symptoms such as headache, asthenia, decreased attention, depressed mood, and flu-like symptoms.

The toxic effects of caffeine occur with intake > 1.2 g. A dose of 10-14 g is considered fatal. Caffeine overdose is rare when considering traditional methods of intake (coffee and tea) because 70-100 cups of coffee should be sufficient for caffeine poisoning. Severe events can occur following the use of caffeine tablets or as energy drinks for the following reasons:

• The episodic consumption of caffeine does not allow for tolerance to develop.
• Young people are more vulnerable to the effects of caffeine.
• Caffeine has a synergistic effect in combination with other components in energy drinks.
• Taking caffeine in combination with alcohol or intense exertion causes serious, even fatal, outcomes.

Products Containing Caffeine

Evidence supports the relationship between high consumption (approximately 1 L) of energy drinks with a caffeine content of 320 mg and short-term cardiovascular adverse events, such as increased BP, QT-segment prolongation corrected for heart rate, and palpitations. These tests prompt the recommendation to avoid consuming these beverages in high quantities and in association with alcohol.

Weight loss products generally contain caffeine coupled with herbal extracts that are expected to improve fat metabolism, lipolysis, and oxidation. These products, because of their easy availability, presumed benefits, and high caffeine concentration, may be more susceptible to misuse because they can be taken in larger portions than recommended. The combination of multiple ingredients, concentrated amounts of caffeine, and excessive consumption increases the likelihood of adverse effects.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Postoperative cognitive dysfunction (POCD) is a form of cognitive decline that involves a functional deterioration of activities of the nervous system, such as selective attention, vigilance, perception, learning, memory, executive function, verbal and language abilities, emotion, visuospatial and visuomotor skills. It occurs in the absence of cranial trauma or other brain injuries, and prevalence rates range from 36.6% in young adults to 42.4% in older adults, as a consequence of significant invasive procedures such as cardiac, noncardiac, and carotid surgeries that are lengthy and intensive.

Alzheimer’s disease (AD), the most common form of dementia, accounts for about two thirds of all cases of dementia globally. It is estimated that 41 million patients with dementia remain undiagnosed worldwide, and 25% of patients are diagnosed only when they are fully symptomatic. AD is a neurodegenerative disorder defined by neuropathologic changes, including beta-amyloid (Abeta) plaques composed of aggregated Abeta and neurofibrillary tangles containing aggregated tau proteins.

Patients with AD are unaware of their condition. Dementia, especially in its early stages, is often a hidden disease. Even when suspected, patients and families may believe that the symptoms are part of normal aging and may not report them to the doctor. In these patients, surgery may unmask subclinical dementia.

The complex correlation between POCD and AD has sparked debate following numerous anecdotal reports of how older adults undergoing surgical procedures may experience long-term cognitive decline with clinical characteristics such as those of patients with dementia. Despite advances in knowledge, it is still difficult to establish a priori how much surgery and anesthesia can increase the risk or accelerate the progression of a prodromal and asymptomatic AD condition (stages I-II) to clinically evident stage III AD. The current trend of an aging population poses a challenge for anesthesiology surgery because as the age of patients undergoing surgery increases, so does the likelihood of developing POCD.

Recent research in these fields has improved knowledge of the characteristics, epidemiology, risk factors, pathogenesis, and potential prevention strategies associated with POCD. It has improved the perspectives of future prevention and treatment.
 

Definition and Diagnostic Criteria

POCD, according to the cognitive impairment classification in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, is characterized by mild neurologic disturbance resulting from routine surgical procedures, excluding conditions such as deafness, dementia, or amnesia. The definition of POCD involves prolonged cognitive decline that can last for weeks, months, or even years. POCD may be confused with postoperative delirium, an acute and fluctuating disorder of consciousness that typically occurs within 3 days of surgery.

The diagnosis of POCD is based primarily on neurocognitive function scales. Widely used assessments include the Montreal Cognitive Assessment, the Wechsler Memory Scale, and the Mini-Mental State Examination.
 

Epidemiology

POCD is prevalent among patients undergoing cardiac or orthopedic surgery. In patients undergoing aortic-coronary bypass and cardiopulmonary bypass, 50%-70% develop POCD 1 week after surgery. In addition, 10%-30% experience long-term effects on cognitive function at 6 months after the procedure. In patients undergoing hip arthroplasty, 20%-50% exhibit POCD within 1 week of surgery, with 10%-14% still presenting it after 3 months.

Risk Factors

Age

POCD is typically observed in patients older than 65 years. However, after surgery, around 30% of younger patients and about 40% of older patients develop POCD at the time of hospital discharge. Specifically, 12.7% of older patients continue to have POCD 3 months after surgery, compared with 5% of younger patients.

Type of Surgery 

Hip and knee arthroplasty procedures entail a higher risk for POCD than general surgery. The same is true of cardiac surgery, especially aortic-coronary bypass and cardiopulmonary bypass.

Types of Anesthesia 

Initial assessments of postoperative cognitive function in cardiac surgery did not provide significant correlations between observed changes and the type of anesthesia because of the high number of confounding factors involved. A more recent meta-analysis of 28 randomized clinical trials concluded that the incidence of POCD is lower in surgeries using intravenous anesthesia with propofol than in those using inhalation anesthesia with isoflurane or sevoflurane.

Pain

Postoperative pain is a common issue, mainly resulting from substantial surgical trauma or potential wound infection. Patient-controlled postoperative analgesia independently increases the risk for POCD, compared with oral postoperative analgesia. Meta-analyses indicate that persistent pain can lead to a decline in patients’ cognitive abilities, attention, memory, and information processing.

Evolving Scenarios

Current research on POCD has deepened our understanding of its pathogenesis, implicating factors such as central nervous system inflammation, neuronal apoptosis, synaptic plasticity damage, abnormal tau protein modification, chronic pain, and mitochondrial metabolic disorders. Several neuroprotective drugs are currently under study, but none have shown consistent benefits for the prevention and treatment of POCD. The available evidence on the subject does not unambiguously guide the practicing physician. But neither does it exclude the importance of a careful assessment of POCD risk factors and the cognitive status of an older patient before surgery to provide useful information to the patient, family, and doctors when deciding on appropriate and shared procedures.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Postoperative cognitive dysfunction (POCD) is a form of cognitive decline that involves a functional deterioration of activities of the nervous system, such as selective attention, vigilance, perception, learning, memory, executive function, verbal and language abilities, emotion, visuospatial and visuomotor skills. It occurs in the absence of cranial trauma or other brain injuries, and prevalence rates range from 36.6% in young adults to 42.4% in older adults, as a consequence of significant invasive procedures such as cardiac, noncardiac, and carotid surgeries that are lengthy and intensive.

Alzheimer’s disease (AD), the most common form of dementia, accounts for about two thirds of all cases of dementia globally. It is estimated that 41 million patients with dementia remain undiagnosed worldwide, and 25% of patients are diagnosed only when they are fully symptomatic. AD is a neurodegenerative disorder defined by neuropathologic changes, including beta-amyloid (Abeta) plaques composed of aggregated Abeta and neurofibrillary tangles containing aggregated tau proteins.

Patients with AD are unaware of their condition. Dementia, especially in its early stages, is often a hidden disease. Even when suspected, patients and families may believe that the symptoms are part of normal aging and may not report them to the doctor. In these patients, surgery may unmask subclinical dementia.

The complex correlation between POCD and AD has sparked debate following numerous anecdotal reports of how older adults undergoing surgical procedures may experience long-term cognitive decline with clinical characteristics such as those of patients with dementia. Despite advances in knowledge, it is still difficult to establish a priori how much surgery and anesthesia can increase the risk or accelerate the progression of a prodromal and asymptomatic AD condition (stages I-II) to clinically evident stage III AD. The current trend of an aging population poses a challenge for anesthesiology surgery because as the age of patients undergoing surgery increases, so does the likelihood of developing POCD.

Recent research in these fields has improved knowledge of the characteristics, epidemiology, risk factors, pathogenesis, and potential prevention strategies associated with POCD. It has improved the perspectives of future prevention and treatment.
 

Definition and Diagnostic Criteria

POCD, according to the cognitive impairment classification in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, is characterized by mild neurologic disturbance resulting from routine surgical procedures, excluding conditions such as deafness, dementia, or amnesia. The definition of POCD involves prolonged cognitive decline that can last for weeks, months, or even years. POCD may be confused with postoperative delirium, an acute and fluctuating disorder of consciousness that typically occurs within 3 days of surgery.

The diagnosis of POCD is based primarily on neurocognitive function scales. Widely used assessments include the Montreal Cognitive Assessment, the Wechsler Memory Scale, and the Mini-Mental State Examination.
 

Epidemiology

POCD is prevalent among patients undergoing cardiac or orthopedic surgery. In patients undergoing aortic-coronary bypass and cardiopulmonary bypass, 50%-70% develop POCD 1 week after surgery. In addition, 10%-30% experience long-term effects on cognitive function at 6 months after the procedure. In patients undergoing hip arthroplasty, 20%-50% exhibit POCD within 1 week of surgery, with 10%-14% still presenting it after 3 months.

Risk Factors

Age

POCD is typically observed in patients older than 65 years. However, after surgery, around 30% of younger patients and about 40% of older patients develop POCD at the time of hospital discharge. Specifically, 12.7% of older patients continue to have POCD 3 months after surgery, compared with 5% of younger patients.

Type of Surgery 

Hip and knee arthroplasty procedures entail a higher risk for POCD than general surgery. The same is true of cardiac surgery, especially aortic-coronary bypass and cardiopulmonary bypass.

Types of Anesthesia 

Initial assessments of postoperative cognitive function in cardiac surgery did not provide significant correlations between observed changes and the type of anesthesia because of the high number of confounding factors involved. A more recent meta-analysis of 28 randomized clinical trials concluded that the incidence of POCD is lower in surgeries using intravenous anesthesia with propofol than in those using inhalation anesthesia with isoflurane or sevoflurane.

Pain

Postoperative pain is a common issue, mainly resulting from substantial surgical trauma or potential wound infection. Patient-controlled postoperative analgesia independently increases the risk for POCD, compared with oral postoperative analgesia. Meta-analyses indicate that persistent pain can lead to a decline in patients’ cognitive abilities, attention, memory, and information processing.

Evolving Scenarios

Current research on POCD has deepened our understanding of its pathogenesis, implicating factors such as central nervous system inflammation, neuronal apoptosis, synaptic plasticity damage, abnormal tau protein modification, chronic pain, and mitochondrial metabolic disorders. Several neuroprotective drugs are currently under study, but none have shown consistent benefits for the prevention and treatment of POCD. The available evidence on the subject does not unambiguously guide the practicing physician. But neither does it exclude the importance of a careful assessment of POCD risk factors and the cognitive status of an older patient before surgery to provide useful information to the patient, family, and doctors when deciding on appropriate and shared procedures.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.

Postoperative cognitive dysfunction (POCD) is a form of cognitive decline that involves a functional deterioration of activities of the nervous system, such as selective attention, vigilance, perception, learning, memory, executive function, verbal and language abilities, emotion, visuospatial and visuomotor skills. It occurs in the absence of cranial trauma or other brain injuries, and prevalence rates range from 36.6% in young adults to 42.4% in older adults, as a consequence of significant invasive procedures such as cardiac, noncardiac, and carotid surgeries that are lengthy and intensive.

Alzheimer’s disease (AD), the most common form of dementia, accounts for about two thirds of all cases of dementia globally. It is estimated that 41 million patients with dementia remain undiagnosed worldwide, and 25% of patients are diagnosed only when they are fully symptomatic. AD is a neurodegenerative disorder defined by neuropathologic changes, including beta-amyloid (Abeta) plaques composed of aggregated Abeta and neurofibrillary tangles containing aggregated tau proteins.

Patients with AD are unaware of their condition. Dementia, especially in its early stages, is often a hidden disease. Even when suspected, patients and families may believe that the symptoms are part of normal aging and may not report them to the doctor. In these patients, surgery may unmask subclinical dementia.

The complex correlation between POCD and AD has sparked debate following numerous anecdotal reports of how older adults undergoing surgical procedures may experience long-term cognitive decline with clinical characteristics such as those of patients with dementia. Despite advances in knowledge, it is still difficult to establish a priori how much surgery and anesthesia can increase the risk or accelerate the progression of a prodromal and asymptomatic AD condition (stages I-II) to clinically evident stage III AD. The current trend of an aging population poses a challenge for anesthesiology surgery because as the age of patients undergoing surgery increases, so does the likelihood of developing POCD.

Recent research in these fields has improved knowledge of the characteristics, epidemiology, risk factors, pathogenesis, and potential prevention strategies associated with POCD. It has improved the perspectives of future prevention and treatment.
 

Definition and Diagnostic Criteria

POCD, according to the cognitive impairment classification in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, is characterized by mild neurologic disturbance resulting from routine surgical procedures, excluding conditions such as deafness, dementia, or amnesia. The definition of POCD involves prolonged cognitive decline that can last for weeks, months, or even years. POCD may be confused with postoperative delirium, an acute and fluctuating disorder of consciousness that typically occurs within 3 days of surgery.

The diagnosis of POCD is based primarily on neurocognitive function scales. Widely used assessments include the Montreal Cognitive Assessment, the Wechsler Memory Scale, and the Mini-Mental State Examination.
 

Epidemiology

POCD is prevalent among patients undergoing cardiac or orthopedic surgery. In patients undergoing aortic-coronary bypass and cardiopulmonary bypass, 50%-70% develop POCD 1 week after surgery. In addition, 10%-30% experience long-term effects on cognitive function at 6 months after the procedure. In patients undergoing hip arthroplasty, 20%-50% exhibit POCD within 1 week of surgery, with 10%-14% still presenting it after 3 months.

Risk Factors

Age

POCD is typically observed in patients older than 65 years. However, after surgery, around 30% of younger patients and about 40% of older patients develop POCD at the time of hospital discharge. Specifically, 12.7% of older patients continue to have POCD 3 months after surgery, compared with 5% of younger patients.

Type of Surgery 

Hip and knee arthroplasty procedures entail a higher risk for POCD than general surgery. The same is true of cardiac surgery, especially aortic-coronary bypass and cardiopulmonary bypass.

Types of Anesthesia 

Initial assessments of postoperative cognitive function in cardiac surgery did not provide significant correlations between observed changes and the type of anesthesia because of the high number of confounding factors involved. A more recent meta-analysis of 28 randomized clinical trials concluded that the incidence of POCD is lower in surgeries using intravenous anesthesia with propofol than in those using inhalation anesthesia with isoflurane or sevoflurane.

Pain

Postoperative pain is a common issue, mainly resulting from substantial surgical trauma or potential wound infection. Patient-controlled postoperative analgesia independently increases the risk for POCD, compared with oral postoperative analgesia. Meta-analyses indicate that persistent pain can lead to a decline in patients’ cognitive abilities, attention, memory, and information processing.

Evolving Scenarios

Current research on POCD has deepened our understanding of its pathogenesis, implicating factors such as central nervous system inflammation, neuronal apoptosis, synaptic plasticity damage, abnormal tau protein modification, chronic pain, and mitochondrial metabolic disorders. Several neuroprotective drugs are currently under study, but none have shown consistent benefits for the prevention and treatment of POCD. The available evidence on the subject does not unambiguously guide the practicing physician. But neither does it exclude the importance of a careful assessment of POCD risk factors and the cognitive status of an older patient before surgery to provide useful information to the patient, family, and doctors when deciding on appropriate and shared procedures.

This story was translated from Univadis Italy, which is part of the Medscape professional network, using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.