In patients with heart disease, is the benefit of lipid-lowering therapy with statins similar in older patients to that in younger patients?

BACKGROUND: Some physicians seem reluctant to treat older patients with statins to lower lipids; they think statins are more effective in high-risk younger patients. This study used existing data from a large study of both older and younger patients to compare the level of benefit in these 2 types of patients.

POPULATION STUDIED: The authors enrolled 9014 patients from 87 centers in Australia and New Zealand who were between the ages of 31 and 75 years. Patients had a history of a myocardial infarction or had been hospitalized for unstable angina. Their baseline total cholesterol was between 155 and 271 mg per dL.

STUDY DESIGN AND VALIDITY: This subgroup analysis of the previously published Long-Term Intervention with Pravastatin in Ischemic Disease (LIPID) study¹ compared the outcomes of the 3514 patients between the ages of 65 and 75 years with the remaining population younger than 65 years. This double-blind placebo-controlled clinical trial randomized patients to receive either placebo or pravastatin (Pravachol) 40 mg per day for an average of 6.1 years. Other lipid-lowering therapy could be used at the discretion of the patients’ usual physician. Both groups received education on a low cholesterol diet. The randomization method and allocation concealment were not specifically addressed.² The groups were similar at the outset of the trial. Data were analyzed on an intention-to-treat basis. An outcomes assessment committee blinded to treatment group assignment reviewed all deaths, myocardial infarctions, and strokes. Although no difference in the relative risk of outcomes was found between age groups, the study was not powered to detect such differences in outcomes by age.

OUTCOMES MEASURED: The main outcome measure was death resulting from coronary heart disease. Secondary end points included nonfatal myocardial infarction (MI), stroke, coronary revascularization, death of any cause including cardiovascular, and duration of hospital stay.

RESULTS: As would be expected, the death rate was higher during the 6 years of study in the group 65 years and older (20.6%) than in the group aged 34 to 64 (9.8%). The risk of MI, unstable angina, and stroke was also significantly higher, though not as marked. In patients older than 65 years, pravastatin decreased overall mortality 21% (95% confidence interval [CI], 7%-32%) and heart disease-related death by 24% (95% CI, 7%-38%), as well as decreasing the rate of MI or stroke. Although the relative risk reduction was similar in older and younger groups, the absolute risk reduction and number needed to treat (NNT) were approximately twice that seen in younger patients. Among older patients, 22 patients would have to be treated for 6 years to prevent 1 of them from dying during this period (NNT=22; 95% CI, 17-36), and 35 to prevent 1 heart disease–related death (NNT=35; 95% CI, 24-67). This benefit was due to the fact that the rate of adverse outcomes (eg, heart disease–related death) was greater in the older age group. There were no differences in the relative risk of the secondary end points by age. The rates of adverse events were not significantly different by age groups.

BACKGROUND: Some physicians seem reluctant to treat older patients with statins to lower lipids; they think statins are more effective in high-risk younger patients. This study used existing data from a large study of both older and younger patients to compare the level of benefit in these 2 types of patients.

POPULATION STUDIED: The authors enrolled 9014 patients from 87 centers in Australia and New Zealand who were between the ages of 31 and 75 years. Patients had a history of a myocardial infarction or had been hospitalized for unstable angina. Their baseline total cholesterol was between 155 and 271 mg per dL.

STUDY DESIGN AND VALIDITY: This subgroup analysis of the previously published Long-Term Intervention with Pravastatin in Ischemic Disease (LIPID) study¹ compared the outcomes of the 3514 patients between the ages of 65 and 75 years with the remaining population younger than 65 years. This double-blind placebo-controlled clinical trial randomized patients to receive either placebo or pravastatin (Pravachol) 40 mg per day for an average of 6.1 years. Other lipid-lowering therapy could be used at the discretion of the patients’ usual physician. Both groups received education on a low cholesterol diet. The randomization method and allocation concealment were not specifically addressed.² The groups were similar at the outset of the trial. Data were analyzed on an intention-to-treat basis. An outcomes assessment committee blinded to treatment group assignment reviewed all deaths, myocardial infarctions, and strokes. Although no difference in the relative risk of outcomes was found between age groups, the study was not powered to detect such differences in outcomes by age.

OUTCOMES MEASURED: The main outcome measure was death resulting from coronary heart disease. Secondary end points included nonfatal myocardial infarction (MI), stroke, coronary revascularization, death of any cause including cardiovascular, and duration of hospital stay.

RESULTS: As would be expected, the death rate was higher during the 6 years of study in the group 65 years and older (20.6%) than in the group aged 34 to 64 (9.8%). The risk of MI, unstable angina, and stroke was also significantly higher, though not as marked. In patients older than 65 years, pravastatin decreased overall mortality 21% (95% confidence interval [CI], 7%-32%) and heart disease-related death by 24% (95% CI, 7%-38%), as well as decreasing the rate of MI or stroke. Although the relative risk reduction was similar in older and younger groups, the absolute risk reduction and number needed to treat (NNT) were approximately twice that seen in younger patients. Among older patients, 22 patients would have to be treated for 6 years to prevent 1 of them from dying during this period (NNT=22; 95% CI, 17-36), and 35 to prevent 1 heart disease–related death (NNT=35; 95% CI, 24-67). This benefit was due to the fact that the rate of adverse outcomes (eg, heart disease–related death) was greater in the older age group. There were no differences in the relative risk of the secondary end points by age. The rates of adverse events were not significantly different by age groups.

BACKGROUND: Some physicians seem reluctant to treat older patients with statins to lower lipids; they think statins are more effective in high-risk younger patients. This study used existing data from a large study of both older and younger patients to compare the level of benefit in these 2 types of patients.

POPULATION STUDIED: The authors enrolled 9014 patients from 87 centers in Australia and New Zealand who were between the ages of 31 and 75 years. Patients had a history of a myocardial infarction or had been hospitalized for unstable angina. Their baseline total cholesterol was between 155 and 271 mg per dL.

STUDY DESIGN AND VALIDITY: This subgroup analysis of the previously published Long-Term Intervention with Pravastatin in Ischemic Disease (LIPID) study¹ compared the outcomes of the 3514 patients between the ages of 65 and 75 years with the remaining population younger than 65 years. This double-blind placebo-controlled clinical trial randomized patients to receive either placebo or pravastatin (Pravachol) 40 mg per day for an average of 6.1 years. Other lipid-lowering therapy could be used at the discretion of the patients’ usual physician. Both groups received education on a low cholesterol diet. The randomization method and allocation concealment were not specifically addressed.² The groups were similar at the outset of the trial. Data were analyzed on an intention-to-treat basis. An outcomes assessment committee blinded to treatment group assignment reviewed all deaths, myocardial infarctions, and strokes. Although no difference in the relative risk of outcomes was found between age groups, the study was not powered to detect such differences in outcomes by age.

OUTCOMES MEASURED: The main outcome measure was death resulting from coronary heart disease. Secondary end points included nonfatal myocardial infarction (MI), stroke, coronary revascularization, death of any cause including cardiovascular, and duration of hospital stay.

RESULTS: As would be expected, the death rate was higher during the 6 years of study in the group 65 years and older (20.6%) than in the group aged 34 to 64 (9.8%). The risk of MI, unstable angina, and stroke was also significantly higher, though not as marked. In patients older than 65 years, pravastatin decreased overall mortality 21% (95% confidence interval [CI], 7%-32%) and heart disease-related death by 24% (95% CI, 7%-38%), as well as decreasing the rate of MI or stroke. Although the relative risk reduction was similar in older and younger groups, the absolute risk reduction and number needed to treat (NNT) were approximately twice that seen in younger patients. Among older patients, 22 patients would have to be treated for 6 years to prevent 1 of them from dying during this period (NNT=22; 95% CI, 17-36), and 35 to prevent 1 heart disease–related death (NNT=35; 95% CI, 24-67). This benefit was due to the fact that the rate of adverse outcomes (eg, heart disease–related death) was greater in the older age group. There were no differences in the relative risk of the secondary end points by age. The rates of adverse events were not significantly different by age groups.