Table 7

Therapies proven effective in diabetes prevention trials

Study (ref.)nPopulationMean age (years)Duration (years)Intervention (daily dose)Incidence in control subjects (%/year)Relative risk reduction (%) (95% CI)3-Year number needed to treat*
Lifestyle
    Finnish DPS (12)522IGT, BMI ≥25 kg/m2553.2I-D&E658 (30–70)8.5
    DPP (11)2,161†IGT, BMI ≥24 kg/m2, FPG >5.3 mmol/l513I-D&E10.458 (48–66)6.9
    Da Qing (13)259†IGT (randomized groups)456G-D&E14.538 (14–56)7.9
    Toranomon Study (31)458IGT (men), BMI = 24 kg/m2∼554I-D&E2.467 (P < 0.043)‡20.6
    Indian DPP (17)269†IGT462.5I-D&E2329 (21–37)6.4
Medications
    DPP (11)2,155†IGT, BMI >24 kg/m2, FPG >5.3 mmol/l512.8Metformin (1,700 mg)10.431 (17–43)13.9
    Indian DPP (17)269†IGT462.5Metformin (500 mg)2326 (19–35)6.9
    STOP NIDDM (15)1,419IGT, FPG >5.6 mmol/l543.2Acarbose (300 mg)12.425 (10–37)9.6
    XENDOS (32)3,277BMI >30 kg/m2434Orlistat (360 mg)2.437 (14–54)45.5
    DREAM (16)5,269IGT or IFG553.0Rosiglitazone (8 mg)9.160 (54–65)6.9
    Voglibose Ph-3 (33)1,780IGT563.0 (1-year Rx)Vogliobose (0.2 mg)12.040 (18–57)21 (1-year Rx)
    ACT-NOW (34)602IGT or IFG522.6Pioglitizone (45 mg)6.881 (61–91)6.3
  • Modified and reprinted with permission (35). Percentage points:

  • *Number needed to treat to prevent 1 case of diabetes, standardized for a 3-year period to improve comparisons across studies.

  • †Number of participants in the indicated comparisons, not necessarily in entire study.

  • ‡Calculated from information in the article. ACT-NOW, ACTos Now Study for the Prevention of Diabetes; DPP, Diabetes Prevention Program; DPS, Diabetes Prevention Study; DREAM, Diabetes Reduction Assessment with Ramipril and Rosiglitazone Medication; STOP NIDDM, Study to Prevent Non-Insulin Dependent Diabetes; XENDOS, Xenical in the prevention of Diabetes in Obese Subjects. I, individual; G, group; D&E, diet and exercise.