WEIGHT-LOSS REVERSES SECONDARY FAILURE OF ORAL HYPOGLYCEMIC AGENTS INOBESE NON-INSULIN-DEPENDENT DIABETIC-PATIENTS INDEPENDENTLY OF THE DURATION OF THE DISEASE

The aim of the present study was to evaluate whether reduction of body weight is able to restore sensitivity to oral hypoglycaemic agents in obese non-insulin-dependent diabetic patients with secondary failure of to the antidiabetic drugs. 80 obese patients (BMI approximately 30 kg/m2) with Type 2 diabetes lasting 1-30 years and showing hyperglycae mia for at least 3 months (51 on insulin, 29 on oral drugs) received a n 800 kcal diet for 20-24 days, lost about 6.3 % BMI, and returned to euglycaemia; 22 obese euglycaemic Type 2 diabet patients (9 on insulin , 13 on oral therapy) underwent the same treatment, and lost approxima tely 8.3 % BMI. As a result insulin could be withdrawn in 18 out of 60 patients and reduced (from 0.5 to 0.2 U.kg day) in the remaining pati ents. Oral therapy could be withdrawn in 17 out of 42 cases and reduce d (from 12.1 to 8.6 mg glibenclamide/day) in the remaining cases. As a control group, 20 non obese (BMI < 24.0 kg/m2) hyperglycaemic Type 2 diabetic patients (10 on oral hypoglycaemic agents, 10 on insulin) wit h Type 2 diabetes lasting 1-26 years, underwent the same dietary regim en, lost about 3.2% of body weight, but could not withdraw insulin, wh ich had to be started in 6 previously oral hypoglycaemic drugs treated patients. Systolic and diastolic blood pressure and serum cholesterol and triglyceride levels also decreased in obese, but not in non-obese Type 2 diabetes patients. These data indicate that : 1) secondary fai lure is of a different nature in non-obese and obese Type 2 diabetic p atients; 2) non insulin dependent diabetes is a progressive disease, e ventually leading to insulin requirement in non obese patients, but no t in the majority of obese patients ; 3) diet retains its therapeutic role in long-lasting Type 2 diabetes; 4) it is likely that, the majori ty of obese Type 2 diabetes patients are unnecessarily treated with in sulin.