Associations between chronic comorbidity and exacerbation risk in primary care patients with COPD

COPD often coexists with chronic conditions that may influence disease prognosis. We investigated associations between chronic (co)morbidities and exacerbations in primary care COPD patients.

Retrospective cohort study based on 2012-2013 electronic health records from 179 Dutch general practices. Comorbidities from patients with physician-diagnosed COPD were categorized according to International Classification of Primary Care (ICPC) codes. Chi-squared tests, uni- and multivariable logistic, and Cox regression analyses were used to study associations with exacerbations, defined as oral corticosteroid prescriptions.

Fourteen thousand six hundred three patients with COPD could be studied (mean age 67 (SD 12) years, 53% male) for two years. At baseline 12,826 (88%) suffered from ≥1 comorbidities, 3263 (22%) from ≥5. The most prevalent comorbidities were hypertension (35%), coronary heart disease (19%), and osteoarthritis (18%). Several comorbidities showed statistically significant associations with frequent (i.e., ≥2/year) exacerbations: heart failure (odds ratio [OR], 95% confidence interval: 1.72; 1.38-2.14), blindness & low vision (OR 1.46; 1.21-1.75), pulmonary cancer (OR 1.85; 1.28-2.67), depression 1.48; 1.14-1.91), prostate disorders (OR 1.50; 1.13-1.98), asthma (OR 1.36; 1.11-1.70), osteoporosis (OR 1.41; 1.11-1.80), diabetes (OR 0.80; 0.66-0.97), dyspepsia (OR 1.25; 1.03-1.50), and peripheral vascular disease (OR 1.20; 1.00-1.45). From all comorbidity categories, having another chronic respiratory disease beside COPD showed the highest risk for developing a new exacerbation (Cox hazard ratio 1.26; 1.17-1.36).

Chronic comorbidities are highly prevalent in primary care COPD patients. Several chronic comorbidities were associated with having frequent exacerbations and increased exacerbation risk.