Review: weight-reducing agents improve glycaemic control and reduce progression to diabetes
Dr S Czernichow, Unite de Recherche en Nutrition Humaine, Bobigny, France;
How do weight-reducing agents affect glycaemic parameters and risk of type 2 diabetes in predisposed individuals?
Included studies were randomised, double-blind, placebo controlled trials (RCTs) that evaluated the effects of weight-reducing agents (eg, orlistat, sibutramine, and rimonabant) on fasting glucose or glycated haemoglobin (HbA1c) concentrations and had a duration of ⩾1 year. Studies of mixed populations were excluded. Outcomes included weight loss, fasting glucose and HbA1c concentrations, and diabetes.
Medline was searched from November 1987 to May 2007. 23 RCTs met the selection criteria: 8 (n = 2848, mean age 55 y) assessed people with diabetes, and 15 (n = 11 821, mean age 44 y) assessed people without diabetes. All RCTs evaluated drug therapy (orlistat, 120 mg/d; sibutramine, 10–20 mg/d; or rimonabant, 20 mg/d) plus reduced-calorie diets. Meta-analysis was not done because of heterogeneity of studies.
Weight loss results are in the table. Weight-reducing agents improved fasting glucose and reduced incidence of diabetes in people without diabetes and decreased HbA1c in those with diabetes (table).
Weight-reducing agents improve glycaemic control and reduce progression to type 2 diabetes in predisposed individuals.
Lloret-Linares C, Greenfield JR, Czernichow S. Effect of weight-reducing agents on glycaemic parameters and progression to type 2 diabetes: a review. Diabet Med 2008;25:1142–50.
Clinical impact ratings: Endocrinology 5/7; Family/general practice 6/7; General/internal medicine 6/7; Obesity 6/7
Use of weight-reducing agents in patients with prediabetes for prevention of progression to type 2 diabetes and for improvement of glycaemic parameters in patients with type 2 diabetes is increasing. The review by Lloret-Linares et al is important because of the global obesity epidemic1 and subsequent increase in development of type 2 diabetes.2 3 Modest weight loss with lifestyle modification can prevent development of type 2 diabetes.4
The primary strength of the review by Lloret-Linares et al is the inclusion of large placebo controlled trials comparing orlistat, sibutramine, and rimonabant for preventing and managing diabetes; similar outcomes were measured across studies. The judicious addition of weight-reducing agents by healthcare providers in overall care plans for overweight patients with prediabetes or diabetes may improve outcomes. Improvement in fasting glucose concentrations and prevention of progression to diabetes in patients with prediabetes, and improvement in glycaemic control in patients with diabetes has the potential to decrease both microvascular and macrovascular complications, thereby, decreasing morbidity, mortality, and healthcare costs.3 Management of overweight is an important part of prevention and management of diabetes. Large trials, translation of research into clinical practice, and development of standards of care that include evidence-based lifestyle modification and weight-reducing agents are urgently needed.