Comparative study to evaluate the effect of l-carnitine plus glimepiride versus glimepiride alone on insulin...

Insulin resistance (IR) is predominant in type 2 diabetic patients. This study aimed to investigate benefits from adding l-carnitine to ongoing glimepiride compared to glimepiride monotherapy on IR in diabetic patients who failed to achieve their glycemic goals on glimepiride monotherapy.

58 patients were recruited from Internal Medicine Department, Tanta University Hospital, Egypt then prospectively randomized to receive their glimepiride dose 2 mg twice daily (group 1) or glimepiride 2 mg twice daily + l-carnitine 1 g m twice daily (group 2) for 6 months. Fasting blood samples were collected at baseline, 3 and 6 months after treatment for analysis of fasting and postprandial blood glucose [FBG &PPBG], glycated hemoglobin [HbA1c %], fasting insulin, extracellular part of insulin regulated aminopeptidase [IRAPe] as a novel marker, tumor necrosis factor-alpha [TNF-α], visfatin and lipid panel. Body mass index [BMI] and homeostasis model assessment of insulin resistance [HOMA-IR] were calculated. Data were statistically analyzed by SPSS using unpaired Student's t-test and one way analysis of variance; p ≤ 0.05 was considered statistically significant.

The obtained data suggested that adding l-carnitine to glimepiride has a significantly beneficial effect on FBG, PPBG, HbA1c, fasting insulin, HOMA-IR index, IRAPe, TNF-α, visfatin and lipid panel parameters but doesn't have effect on BMI and blood pressure.

The co-administration of l-carnitine with glimepiride represents a new therapeutic strategy for better controlling diabetic patients as it resulted in more beneficial effects on direct and indirect biomarkers of insulin resistance than glimepiride alone.