Treating prediabetes with metformin Systematic review and meta-analysis

Primary Healthcare Research Unit, Health Science Centre, 300 Prince Philip Drive, St John's, Newfoundland.
Canadian family physician Medecin de famille canadien (Impact Factor: 1.4). 05/2009; 55(4):363-9.
Source: PubMed

ABSTRACT To determine if the use of metformin in people with prediabetes (impaired glucose tolerance or impaired fasting glucose) would prevent or delay the onset of frank type 2 diabetes mellitus.
MEDLINE was searched from January 1966 to the present, and articles meeting the selection criteria were hand searched.
Randomized controlled trials that involved administration of metformin to delay or prevent type 2 diabetes in individuals with impaired glucose tolerance or impaired fasting glucose were included. Development of diabetes was a required outcome measure; follow-up time of at least 6 months was required. Three studies met these criteria.
The 3 studies varied in ethnicity of the population studied, in the rates of conversion to diabetes from prediabetes, and in the dose of metformin used. In general the studies were well done, although 2 of the 3 did not do true intention-to-treat analyses. A sensitivity analysis was completed by converting all data to intention-to-treat data and assuming a worst-case scenario for the people who were lost to follow-up.
Metformin decreases the rate of conversion from prediabetes to diabetes. This was true at higher dosage (850 mg twice daily) and lower dosage (250 mg twice or 3 times daily); in people of varied ethnicity; and even when a sensitivity analysis was applied to the data. The number needed to treat was between 7 and 14 for treatment over a 3-year period.

  • Source
    • "Metformin is only approved for use in patients with diabetes, and use in non-diabetic patients is presently considered an 'off-label' prescription. However, metformin has previously been used in non-diabetic patients, for example, to induce ovulation in women with polycystic ovary syndrome (Ng et al., 2001) and for the prevention of type 2 diabetes in predisposed patients (Lilly and Godwin, 2009). The aim of this study was to determine the effect of metformin treatment on antipsychotic-induced weight gain in non-diabetic patients, by means of a systematic review and a meta-analysis. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Weight gain is a clinically important side effect of antipsychotic drug therapy. The aim of this study was to determine the effect of the antidiabetic drug metformin on antipsychotic-induced weight gain in non-diabetic patients. In a systematic literature review we identified 195 citations from which seven randomized, placebo-controlled studies (398 patients) were included in the final analysis. Studies in adults (n = 5) and in children (n = 2) were analysed separately. Compared with placebo, metformin treatment caused a significant body weight reduction in adult non-diabetic patients treated with atypical antipsychotics (4.8%, 95% CI 1.6 to 8.0) and in children (4.1%, 95% CI 2.2 to 6.0). There was evidence of substantial heterogeneity among studies, and when the analysis was restricted to patients with a manifest (>10%) body weight increase prior to randomisation metformin reduced weight by 7.5% (95% CI 2.9 to 12.0). The effect was larger in Asians (7.8%, 95% CI 4.4 to 11.2) than in Hispanics (2.0%, 95% CI 0.7 to 3.3). In conclusion, metformin has a pronounced weight-reducing effect in antipsychotic-treated patients, especially in those with a manifest weight gain. Although direct comparisons are lacking, the observed effect on body weight compares favourably with the effect of sibutramine and orlistat, approved for weight reduction. However, metformin is not approved for use in non-diabetic patients and it is still not generally advisable to recommend metformin to counteract antipsychotic-induced weight gain.
    Journal of Psychopharmacology 03/2011; 25(3):299-305. DOI:10.1177/0269881109353461 · 2.81 Impact Factor
  • Source
  • [Show abstract] [Hide abstract]
    ABSTRACT: Diabetic retinopathy (DR) is the leading cause of blindness in people of working age. The purpose of this paper is to report the prevalence and cardiovascular associations of diabetic retinopathy and maculopathy (DMac) in Germany. The Gutenberg Health Study (GHS) is a population-based study with 15,010 participants aged between 35 at 74 years from the city of Mainz and the district of Mainz-Bingen. We determined the weighted prevalence of DR and DMac by assessing fundus photographs of persons with diabetes from the GHS data base. Diabetes was defined as HbA1c ≥ 6.5%, known diagnosis diabetes mellitus or known diabetes medication. Furthermore, we analysed the association between DR and cardiovascular risk factors and diseases. Overall, 7.5% (1,124/15,010) of the GHS cohort had diabetes. Of these, 27.7% were unaware of their disease and thus were newly diagnosed by their participation in the GHS. The prevalence of DR and DMac was 21.7% and 2.3%, respectively among patients with diabetes. Vision-threatening disease was present in 5% of the diabetic cohort. In the multivariable analysis DR (all types) was associated with age (Odds Ratio [95% confidence interval]: 0.97 [0.955-0.992]; p = 0.006) arterial hypertension (1.90 [1.190-3.044]; p = 0.0072) and vision-threatening DR with obesity (3.29 [1.504-7.206]; p = 0.0029). DR (all stages) and vision-threatening DR were associated with duration of diabetes (1.09 [1.068-1.114]; p<0.0001 and 1.18 [1.137-1.222]; p<0.0001, respectively). Our calculations suggest that more than a quarter-million persons have vision-threatening diabetic retinal disease in Germany. Prevalence of DR was lower in the GHS compared to East-Asian studies. Associations were found with age, arterial hypertension, obesity, and duration of diabetes mellitus.
    PLoS ONE 10(6):e0127188. DOI:10.1371/journal.pone.0127188 · 3.53 Impact Factor
Show more


Available from