Efficacy and Effectiveness of Screen and Treat Policies in Type 2 Diabetes Prevention
January 4, 2017. This systematic review and meta-analysis was conducted to assess the diagnostic accuracy (sensitivity and specificity) of A1C and fasting plasma glucose (FPG) used as screening tests for prediabetes and the efficacy of lifestyle or metformin intervention in preventing the transition from prediabetes to type 2 diabetes (T2D). The final analysis included 49 screening studies and 50 intervention trials. A1C was not sensitive (0.49) or specific (0.79) in detecting prediabetes, while FPG was not sensitive (0.25) but was highly specific (0.94). This led the investigators to note that, when used alone, “screen and treat” policies may not have a substantial impact on diabetes incidence. However, interventions developed to delay the transition from prediabetes to diabetes did show beneficial impact: over a period of 6 months to 6 years, lifestyle interventions were associated with a 36% relative risk reduction in transition to T2D. Metformin use reduced the transition from prediabetes to diabetes by 26%, as measured at the end of the trial period.