In a recently published paper , the Diabetes Prevention Program randomized trial provides more information from its database considering the effect of progression from impaired glucose tolerance (IGT) to diabetes on cardiovascular risk factors and its amelioration by intensive lifestyle and metformin intervention.
There is a known increase of cardiovascular disease in subjects with diabetes, but the evolution of this risk in patients progressing from prediabetes to diabetes is not understood. In this study, 3234 patients with IGT were followed for 3.2 years and randomized to intensive lifestyle (ILS) intervention (achieve and maintain a 7% weight reduction in initial body weight using a low-calorie, low-fat diet and 150 min/week of moderate physical activity), metformin (850 mg twice a day) or placebo .
This study examines the longitudinal relationship between selected risk factors for cardiovascular disease (blood pressure, triglycerides, high density lipoprotein (HDL) and low density lipoprotein (LDL) cholesterol, and LDL peak particle density) and glycemia in the three treatment groups in the Diabetes Prevention Program. Values of the risk factors for cardiovascular disease and changes from baseline became more unfavorable as glucose tolerance status deteriorated but improved with reversion to normal glucose tolerance, especially in the ILS intervention group (trend test p < 0.001 for all risk factors except LDL peak particle density (p = 0.02) in the ILS group and HDL cholesterol (p = 0.02) in the placebo group). Also, while the glucose tolerance status was improved in the ILS group, systolic blood pressure and triglyceride levels fell by 25%, whereas HDL cholesterol increased by 8%; the metformin and placebo groups showed less significant improvements. Although there were few significant differences in the transition from IGT to diabetes, there were strong relationships between risk factors and continuous measures of glycemia.
Progression from IGT to diabetes is associated with mild deterioration, whereas reversion to normal glucose tolerance is associated with improvement in cardiovascular risk factors. Early intervention with intensive lifestyle, but less so with metformin, in participants at high risk for diabetes improves the cardiovascular risk and glucose tolerance profile simultaneously.
Department of Obstetrics & Gynecology, Complejo Hospitalario Metropolitano, Caja del Seguro Social de Panama
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