| Abstrakt: |
Recently published results from observational studies suggest that compared with sulfunylurea therapy (SU), metformin (MET) may protect against mortality whereas the effect of MET and SU combination has on mortality is controversial. These studies were however conducted on data gathered in the early 1990's when first generation SUs were still largely being used, We conducted a population-based cohort study using Quebec Health data. Eligible for cohort entry were individuals aged ≥ 66 years, newly dispensed an oral antidiabetics (OAD) during 1998-2003 with continuous drug plan coverage of ≥ 1 year before OAD initiation. Individuals were followed from treatment initiation up to either December 31, 2004, ineligibility to the drug plan, discontinuation of OAD, add-on of another OAD, or death. The outcome was death from any cause. Hazard ratios (HR) and their 95% confidence intervals (CI) were calculated using multivariate Cox regression analysis models. Potential confounding variables included age, sex, use of nitrates in the year preceding OAD initiation, and co-morbidity score. A total of 36,429, 18,528, and 2,548 individuals received as their initial therapy MET, a SU, or a combination of MET and SU, respectively. During each of the first three 1.75-year periods following OAD initiation, the risk of all-cause mortality was lower among individuals initially dispensed MET than among those who received a SU (adjusted HRs: 0.63, 0.76 and 0.83; P< 0.05). Compared with individuals initially dispensed a SU, those who received a combination therapy had an increased risk during each of the first two 1.75-year periods (adjusted HRs: 1.19 and 1.34; P< 0.05). These results confirm previous findings, suggesting that as compared with SU, MET is associated with decreased mortality. However, exposure to both MET and SU could increase mortality in type 2 diabetes. Further study is needed as to whether combination of MET with safer agents might decrease risk of mortality. [ABSTRACT FROM AUTHOR] |
