Mortality increased by 58% in first-line Sulfonylurea therapy for Type 2 Diabetes

by Bruce Sylvester – Research presented on September 26, 2013 the European Association for the Study of Diabetes (EASD) annual meeting in Barcelona, Spain, indicates that type 2 diabetes patients receiving first-line sulfonylurea treatment have significantly higher mortality than those receiving metformin.

The investigators concluded that sulfonylurea first-line treatment might no longer be appropriate.

As background, the researchers noted that sulfonylureas, like glipizide, gliclazide or glibenclamide, are often prescribed as first-line therapy, with about 7% of people with type 2 diabetes receiving them in the UK.  Metformin is the most commonly prescribed first-line treatment.

Dr. Craig Currie, professor of pharmacoepidemiology at Cardiff University, Cardiff, UK, and his colleagues evaluated retrospectively data from the Clinical Practice Research Datalink (CPRD), a databank including approximately 10% of all patients treated in primary care in the United Kingdom.

They selected patients with type 2 diabetes who began first-line, glucose-lowering treatments between 2000 and 2012. The primary endpoint was all-cause mortality.

They made a matched-cohort study comparing those treated with sulfonylureas (exposed) versus metformin (non-exposed), matching subjects by the following baseline criteria: age (±2 years), gender, year of index exposure, diabetes duration (±1 year), BMI (±3 kg/m2), serum creatinine (±10 μmol/l) and Hba1c (±1%).

They identified 76,811 patients who received metformin monotherapy (mean follow-up 3 years), and 15,687 who received a first-line sulfonylurea (mean follow-up 3 years).

They included 2,048 subjects in each arm of the direct matched cohorts, and 8,836 in the propensity matched cohorts.

They found that subjects using a first-line sulfonylurea were 58% more likely to die from any cause than those prescribed metformin.

“Mortality was significantly increased in patients prescribed sulfonylureas as first-line, glucose lowering monotherapy, compared with metformin monotherapy. Whilst residual confounding and confounding by indication may remain, this study indicates that treatment with first-line monotherapy with sulfonylureas should be reconsidered,” Currie said.