The American College of Physicians ( ACP ) has developed a guideline to present the evidence and provide clinical recommendations on the comparative effectiveness and safety of type 2 diabetes medications.
A total of 66 studies ( 46 RCTs; duration, 12 weeks to 6 years ) have reported comparative effectiveness of oral diabetes medications on long-term outcomes. The mean age of participants ranged from 48 years to 75 years.
It was difficult to draw conclusions about the comparative effectiveness of type 2 diabetes medications on all-cause mortality, cardiovascular morbidity and mortality, and microvascular outcomes because of low quality or insufficient evidence.
Five RCTs and 11 observational studies were examined for all-cause mortality between Metformin monotherapy and sulfonylurea monotherapy. These studies have indicated that Metformin was associated with lower all-cause mortality compared with sulfonylureas ( low-quality evidence ).
Metformin was also favored over sulfonylureas for cardiovascular mortality ( low-quality evidence ), as evidenced by ADOPT ( A Diabetes Outcome Progression Trial ) and 4 cohort studies, although 1 prospective cohort study has shown a slightly higher cardiovascular mortality rate for Metformin than for sulfonylurea monotherapy.
Monotherapy with Metformin was linked to lower cardiovascular morbidity than combination therapy for Metformin plus sulfonylureas ( low-quality evidence ), as shown by 1 RCT ( 5% vs. 14% adverse cardiovascular events ) and 1 cohort study ( adjusted incidence of hospitalization for myocardial infarction or coronary revascularization, 13.90 vs. 19.44 per 1000 person-years ). Evidence for all other comparisons was insufficient or unclear.
There was moderate-quality evidence for nephropathy only for the comparison between Pioglitazone and Metformin. In the 2 studies that addressed this comparison, Pioglitazone has significantly reduced the urinary albumin–creatinine ratio by 19% and 15%, whereas the ratio was unchanged in patients treated with Metformin. ( Xagena )
Source: Annals of Internal Medicine, 2012