Therapeutic effect of tolbutamide in non-insulin dependent diabetes mellitus (NIDDM). Relation to beta-cell function.
The therapeutic effect of tolbutamide (1.5 g daily) in a random sample of patients with non-insulin dependent diabetes mellitus (NIDDM), was studied in a controlled, double-blind cross-over trial of 13 women and 6 men, aged 40-65 years and of 85-155% ideal body weight. The trial comprised C-peptide determinations during a standard carbohydrate rich meal followed by four periods of 3 months in which alternating tolbutamide and placebo were given. From the beginning to the end of the treatment periods fasting blood glucose was reduced from 11.9 +/- 1.1 (mean +/- SEM) to 10.0 +/- 0.8 mmol/l (P less than 0.025), glycohaemoglobin from 12.8% +/- 0.7 to 11.3% +/- 0.5 (P less than 0.02) with a close correlation between fasting blood glucose and glycohaemoglobin (r = 0.87, P less than 0.001). The observations during the first 3 months of study was not included in the calculations. Fasting C-peptide and fasting insulin concentrations were not significantly altered by tolbutamide treatment. The effect of tolbutamide was inversely correlated to the C-peptide response to the standard test meal at the start of the trial (r = 0.76, P less than  0.01), so that patients with the most pronounced beta-cell failure had the greatest therapeutical effect. The beta-cell response to the test meal could not identify patients, whose fasting blood glucose would be normalized by tolbutamide treatment.
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D002096:C-Peptide / Q000097:blood; D002986:Clinical Trials as Topic; D003920:Diabetes Mellitus / Q000097:blood / Q000188:drug therapy*; D004311:Double-Blind Method; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007328:Insulin / Q000378:metabolism / Q000627:therapeutic use; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011897:Random Allocation; D014044:Tolbutamide / Q000627:therapeutic use*
D001786:Blood Glucose; D002096:C-Peptide; D006442:Glycated Hemoglobin; D007328:Insulin; D014044:Tolbutamide