Conclusions HbA1c is neither sensitive nor specific for detecting pre‐diabetes ; fasting glucose is specific but not sensitive .
Interventions in people classified through screening as having pre‐diabetes have some efficacy in preventing or delaying onset of type 2 diabetes in trial population s. As screening is inaccurate , many people will receives an incorrect diagnosis and be referred on for interventions while others will be falsely reassured and not offered the intervention .
These findings suggest that “ screen and treat ” policies alone are unlikely to have substantial impact on the worsening epidemic of type 2 diabetes .
& NA ; Objectives To assess diagnostic accuracy of screening tests for  pre‐diabetes  and efficacy of interventions ( lifestyle or metformin ) in preventing onset of type 2 diabetes in people with pre‐diabetes .
Enhanced fitness: a randomized controlled trial of the effects of home-based physical activity counseling on glycemic control in older adults with prediabetes mellitus.
OBJECTIVES To determine whether a home-based multicomponent physical activity counseling ( PAC ) intervention is effective in reducing glycemic measures in older out patients with prediabetes mellitus . DESIGN Controlled clinical trial . SETTING Primary care clinics of the Durham Veterans Affairs ( VA ) Medical Center between September 29 , 2008 , and March 25 , 2010 . PARTICIPANTS Three hundred two overweight ( body mass index 25 - 45 kg/m(2 ) ) , older ( 60 - 89 ) out patients with impaired glucose tolerance ( fasting blood glucose 100 - 125 mg/dL , glycosylated hemoglobin ( HbA1c ) < 7 % ) r and omly assigned to a  PAC intervention group  ( n = 180 ) or a usual care control group ( n = 122 ) . INTERVENTION A 12-month , home-based multicomponent PAC program including one in-person baseline counseling session , regular telephone counseling , physician endorsement in clinic with monthly automated encouragement , and customized mailed material s. All study participants , including controls , received a consultation in a VA weight management program . MEASUREMENTS The primary outcome was a homeostasis model assessment of insulin resistance ( HOMA-IR ) , calculated from fasting insulin and glucose levels at baseline and 3 and 12 months . HbA1c was the secondary indicator of glycemic control . Other secondary outcomes were anthropometric measures and self-reported physical activity , health-related quality of life , and physical function . RESULTS There were no significant differences between the PAC and control groups over time for any of the glycemic indicators . Both groups had small declines over time of approximately 6 % in fasting blood glucose ( P < .001 ) , and other glycemic indicators remained stable . The declines in glucose were not sufficient to affect the change in HOMA-IR scores due to fluctuations in insulin over time . Endurance physical activity increased significantly in the PAC group ( P < .001 ) and not in the usual care group . CONCLUSION Home-based telephone counseling increased physical activity levels but was insufficient to improve glycemic indicators in older out patients with prediabetes mellitus
Conclusions HbA1c is neither sensitive nor specific for detecting pre‐diabetes ; fasting glucose is specific but not sensitive .
Interventions in people classified through screening as having pre‐diabetes have some efficacy in preventing or delaying onset of type 2 diabetes in trial population s. As screening is inaccurate , many people will receives an incorrect diagnosis and be referred on for interventions while others will be falsely reassured and not offered the intervention .
These findings suggest that “ screen and treat ” policies alone are unlikely to have substantial impact on the worsening epidemic of type 2 diabetes .
& NA ; Objectives To assess diagnostic accuracy of screening tests for  pre‐diabetes  and efficacy of interventions ( lifestyle or metformin ) in preventing onset of type 2 diabetes in people with pre‐diabetes .