Thiazolidinediones, also known as "glitazones", are known to improve insulin secretion as well as decrease insulin resistance. A previous study known as the ACT NOW study was done to see if using drugs that improve insulin and decrease insulin resistance can reduce the incidence of type 2 diabetes in high risk subjects. This current study further elaborates on this previous study by determining exactly what metabolic and physiologic changes are responsible for the prevention of diabetes as well as the progression to diabetes.
The ACT NOW study was performed over a 2.4 year period. A total of 602 subjects participated in the study with about 441 subjects completing the study. Subjects were randomized to receive pioglitazone (Actos) 30mg or a placebo. The dose of the pioglitazone was increased to 45 mg after 1 month. The subjects were monitored every 2 months for the first year and every 3 months thereafter until they either reached the end of the study, dropped out, or developed diabetes. The follow-up results show that diabetes developed in 19.7% of the placebo group, and 7% of the pioglitazone (Actos) group. The current study assessed that β-cell compensation was higher in patients on pioglitazone compared to placebo. Therefore, the preservation and the restoration of β-cell function is key in diabetes prevention in pioglitazone treatment.
In conclusion, the main reason why pioglitazone is effective in preventing diabetes incidence in patients is due to the fact that their β-cell function is more improved than those patients not on pioglitazone.
- Preservation and improvement in β-cell function is the main mechanism by which pioglitazone prevents diabetes and glucose tolerance.
- Pioglitazone should be considered in those patients that are high risk for developing diabetes, like those with an impaired fasting glucose and/or impaired glucose tolerance.
Diabetes/Metabolism Research & Reviews 2014: Defronzo, R. et al. "Prevention of Diabetes With Pioglitazone in ACT NOW." Diabetes. 2013; 62(11):3920-3926