Diabetes risks and outcomes in chronic obstructive pulmonary disease patients: Two nationwide population-based retrospective cohort studies

The relationship between chronic obstructive pulmonary disease (COPD) and diabetes remains incompletely understood. This study evaluated diabetes risk and post-diabetes outcomes in COPD patients with and without exacerbations. We identified 4671 adults newly diagnosed with COPD exacerbations and 9342 adults newly diagnosed with COPD without exacerbations during 2000-2008 using Taiwan's National Health Insurance Research Database. A comparison cohort of 18684 adults without COPD, matched by age and sex, was randomly selected from the same dataset for the control group. Diabetes events during 2000-2013 were ascertained from medical claims during the follow-up period. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of diabetes associated with COPD with or without exacerbations were calculated. We conducted another nested cohort study of 395516 patients with diabetes hospitalization during 2002-2013 and calculated adjusted odds ratios (ORs) and 95% CIs of histories of COPD and COPD exacerbations associated with adverse events after diabetes admission. During the follow-up period, the incidences of diabetes for patients without COPD and for patients with COPD without or with exacerbations were 3.4, 4.1 and 7.4 per 1000 person-years, respectively (P < 0.0001). Increased risk of diabetes for patients with COPD without exacerbations (HR 1.09, 95% CI 1.02-1.17) and COPD with exacerbations (HR 2.18, 95% CI 1.88-2.52) was noted. Post-diabetes pneumonia (OR 3.28, 95% CI 3.13-3.43), intensive care admission (OR 1.32, 95% CI 1.26-1.39) and mortality (OR 2.06, 95% CI 1.88-2.25) were associated with COPD exacerbations. Prevention and intervention strategies for diabetes and post-diabetes outcomes are needed for this susceptible population.