Effect of pioglitazone on insulin secretion in patients with both impaired fasting glucose and impaired glucose tolerance

Medical Research Unit in Clinical Epidemiology, Hospital of Specialties, Medical Unit of High Specialty, West National Medical Center, Mexican Institute of Social Security, Guadalajara, Mexico.
Diabetes Research and Clinical Practice (Impact Factor: 2.54). 02/2007; 75(1):115-8. DOI: 10.1016/j.diabres.2006.05.003
Source: PubMed


To evaluate the effect of a thiazolidinedione, pioglitazone, on insulin secretion in patients with both impaired fasting glucose and impaired glucose tolerance.
A randomized, double-blind, placebo-controlled clinical trial was carried out in 18 overweight or obese patients with both impaired fasting glucose and impaired glucose tolerance. Pharmacological intervention consisted of an oral morning administration of pioglitazone (30 mg) or a placebo with a similar presentation for 30 days. Before and after the intervention, glucose, creatinine, lipid profile and uric acid concentrations were measured. To evaluate insulin secretion (early, late and total phases) and insulin sensitivity, a hyperglycemic-hyperinsulinemic clamp was also performed.
There were significant reductions (p=0.008) in fasting insulin concentration (121 versus 45 pmol/l), late (565 versus 307 pmol/l) and total insulin secretion (474 versus 254 pmol/l), as well as, in 2h postload glucose levels (9.7 versus 6.9 mmol/l, p=0.028), with an increment in insulin sensitivity after pioglitazone administration (7.5 versus 9.9).
Pioglitazone administration during a period of 4 weeks decreased late and total insulin secretion phases, fasting insulin and 2h postload glucose levels, and improved insulin sensitivity in patients with both impaired fasting glucose and impaired glucose tolerance.

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