Risk factors for 30-day hospital readmission after an exacerbation of chronic obstructive pulmonary disease (COPD) differed by sex, according to a study published in the Annals of the American Thoracic Society.
Researchers of this retrospective analysis assessed the sex differences of comorbidities associated with COPD exacerbation in veterans to determine risk factors for 30-day hospital readmission. Veterans from Veterans Health Affairs facilities were included in this study if they were hospitalized for a COPD exacerbation, as identified by the International Classification of Disease, 9th Revision codes for COPD and emphysema. Demographic information, clinical data, mental health conditions, smoking status, medication usage, and hospitalization accounts were collected from electronic medical records.
Of the 48,888 patients hospitalized during the course of 4 years for COPD exacerbation, 4% were women. Compared with men, women were younger (62 years vs 69 years) and were more likely to be a current smoker (71% vs 62%), have asthma (39% vs 17%), have psychiatric comorbidities, and have a drug use disorder (15% vs 12%). For treatment before hospitalization, women were more likely than men to receive nicotine replacement therapies (24% vs 15%; P <.01) and less likely to receive antimuscarinics (43% vs 48%; P <.01) or combined long-acting beta agonist/inhaled corticosteroid inhalers (61% vs 64%; P =.04).
The 30-day hospital readmission rate was lower in women (20% vs 22%; P =.01) than in men. Using a multivariable logistic regression model stratified by sex, the variables of older age, congestive heart failure, anxiety, and drug use were associated with 30-day hospital readmission for both sexes while race, diabetes, major depressive disorder, alcohol use, and antimuscarinic inhaler usage were significant risks for readmission in men.
Limitations to this study included its retrospective design, the potential for a sex bias in COPD exacerbation coding, a lack of data on spirometry values, socioeconomic status, and symptom burden, and the potential for the younger average age of the women’s cohort to affect group differences.
“Women veterans with COPD have a unique phenotype compared to men, including a younger presentation, higher smoking rates, and unique comorbidities,” the researchers concluded.
Bade BC, DeRycke EC, Ramsey C, et al. Sex differences in veterans admitted to the hospital for COPD exacerbation [published online March 1, 2019]. Ann Am Thorac Soc. doi:10.1513/AnnalsATS.201809-615OC