Predictors of response to glimepiride in patients with type 2 diabetes mellitus

Objective: The purpose of DIAMETRE (D/abete et Amarel en Monotherapie, Etude de Titration pour la definition des Repondeurs) was to identify factors predictive of response to glimepiride monotherapy in type 2 diabetic patients in the setting of a prospective multicentre open study. Material and methods: Patients aged 35-70 years with poorly controlled diabetes [fasting plasma glucose (FPG) greater than or equal to 1,40 g/l and < 3 g/l at baseline] were treated with glimepiride for 6 months, with dosage titrated from 1-6 mg daily, depending on the monthly FPG measurement. Responders were defined as patients with a) FPG < 7.78 mmol/l (1.40 g/l) and HbA(1c) < 7.5% at endpoint, or b) decrease in FPG greater than or equal to 20% and/or HbA(1c) greater than or equal to 10%. Stepwise logistic regression analysis was used to identify factors predictive of response. Results: Of 849 patients evaluable for efficacy, 483 (56.9%) were responders. The response was independently influenced by prior treatment with OADs [OR: 0.399 (0.290-0.549), p = 0.0001] and diabetes duration [OR: 0.912 (0.877-0.948), p = 0.0001]. Ninety patients (9.2%) experienced 124 episodes of symptomatic hypoglycaemia. Multivariate analysis revealed that a high level of HbA(1c) decreased the risk of symptomatic hypoglycaemia [OR: 0.734 (0.628; 0.858), p = 0.0001] whereas a family history of type 2 diabetes doubled this risk [OR: 1.956 (1.246; 3.072), p = 0.003]. Conclusion: This large-scale study, conducted under conditions approximating to current medical practice, confirms that glimepiride has a favourable risk-benefit ratio in type 2 diabetes mellitus. Diabetes duration and previous treatment with OADs reduced the likelihood of being a responder to treatment.