Relationship between glycemic control and chronic obstructive pulmonary disease in patients with type 2 diabetes: A nested case-control study

AIMS To evaluate the relationship between glycemic control and plasma glycated hemoglobin (HbA1c) levels in patients with type 2 diabetes mellitus (T2D) and the risk of chronic obstructive pulmonary disease (COPD). METHODS We conducted a population-based, retrospective, nested, case-control study involving 124,876 patients with DM2 from the Canary Islands, Spain. From the cohort, we selected all COPD cases and, for each case, five control subjects who were COPD free. We analyzed the association between glycemic control, HbA1c level and incident COPD. RESULTS A total of 1320 incidence cases of COPD (1.06%) were identified and matched individually with 6600 controls according to age and sex. After multivariate adjustment, the COPD risk increased among patients with poor glycemic control compared to patients with good glycemic control [HbA1c levels