Atrial fibrillation is being seen with increasing frequency in patients admitted to U.S. hospitals for exacerbations of end-stage chronic obstructive pulmonary disease, based on a retrospective analysis of data from the Nationwide Inpatient Sample.
The prevalence of atrial fibrillation (AFib) among patients with end-stage chronic obstructive pulmonary disease (COPD) on home oxygen who were admitted with COPD exacerbations increased from 12.9% in 2003 to 21.3% in 2014, according to Xiaochun Xiao of the department of health statistics at Second Military Medical University in Shanghai and colleagues.
Additionally, “we found that comorbid [AFib] was associated with an increased risk of the need for mechanical ventilation, especially invasive mechanical ventilation. Moreover, comorbid [AFib] was associated with adverse clinical outcomes, including increased in-hospital death, acute respiratory failure, acute kidney injury, sepsis, and stroke,” the researchers wrote in the study published in the journal CHEST.
Patients included in the study were aged at least 18 years, were diagnosed with end-stage COPD and on home oxygen, and were hospitalized because of a COPD-related exacerbation. Based on 1,345,270 weighted hospital admissions of adults with end-stage COPD on home oxygen who met the inclusion criteria for the study, 18.2% (244,488 admissions) of patients had AFib, and the prevalence of AFib in COPD patients increased over time from 2003 (12.9%) to 2014 (21.3%; P less than .0001).
Patients with AFib, compared with patients without AFib, were older (75.5 years vs. 69.6 years; P less than .0001) and more likely to be male (50.7% vs. 59.1%; P less than .0001) and white (80.9% vs. 74.4%; P less than .0001). Patients with AFib also had higher stroke risk reflected in higher CHA2DS2-VASc scores (3.26 vs. 2.45; P less than .0001), and higher likelihood of in-hospital mortality and readmission reflected in Elixhauser scores greater than or equal to 4 (51.2% vs. 35.6%).
In addition, the prevalence of AFib increased with increasing income. Larger hospitals in terms of bed size, urban environment, and Medicare insurance status also were associated with a higher AFib prevalence.
AFib was associated with an increased cost of $1,415 and an increased length of stay of 0.6 days after adjustment for potential confounders. AFib also predicted risk for several adverse events, including stroke (odds ratio, 1.80; in-hospital death, [OR, 1.54]), invasive mechanical ventilation (OR, 1.37), sepsis (OR, 1.23), noninvasive mechanical ventilation (OR, 1.14), acute kidney injury (OR, 1.09), and acute respiratory failure (OR, 1.09).
The researchers noted the database could have potentially overinflated AFib prevalence, as they could not differentiate index admissions and readmissions. The database also does not contain information about secondary diagnoses codes present on admission, which could make it difficult to identify adverse events that occurred during hospitalization.
“Our findings should prompt further efforts to identify the reasons for increased [AFib] prevalence and provide better management strategies for end-stage COPD patients comorbid with [AFib],” the researchers concluded.
This study was funded by a grant from the Fourth Round of the Shanghai 3-year Action Plan on Public Health Discipline and Talent Program. The authors reported no relevant conflict of interest.
SOURCE: Xiao X et al. CHEST. 2019 Jan 23. doi: 10.1016/j.chest.2018.12.021.