The relationship between antihypertensive combination therapies comprising diuretics and/or beta-blockers and the risk of new-onset diabetes: a retrospective longitudinal cohort study.

We investigate the associations of antihypertensive drugs in double and triple combination regimens comprising diuretics and/or beta-blockers on the development of new-onset diabetes (NOD). This study was a retrospective cohort study carried out using data from claim forms provided to the central regional branch of the Bureau of National Health Insurance (BNHI) in Taiwan from January 2001 to December 2006. We estimated the odds ratios (ORs) of NOD associated with antihypertensive combination therapy use; non-NOD individuals served as the reference group. A total of 2361 NOD cases were identified among the 12,386 hypertensive patients (6143 men and 6243 women, aged 28-86 years (mean age: 68+11)) during the study period. The risk of NOD was higher after adjusting for age and sex among users of double combinations of diuretics plus beta-blockers (adjusted OR, 1.25; 95% confidence interval (CI): 1.12-1.58), diuretics plus calcium channel blockers (CCBs; adjusted OR: 1.14; 95% CI: 1.06-1.26) and beta-blockers plus calcium channel blockers (adjusted OR: 1.12; 95% CI: 1.04-1.29) than that among non-users. Patients who took angiotensin-converting enzyme (ACE) inhibitors, or alpha-blockers as part of a double-drug regimen were at a lower risk of developing NOD than were non-users. Double- or triple-drug combinations comprising angiotensin receptor blockers (ARBs) and vasodilators were not associated with risk of NOD. The results of this study suggest that users of double-drug combination therapies containing diuretics and/or beta-blockers and an ACE inhibitor or alpha-blocker are at a significantly lower risk of developing NOD than are other classes.