Effects of pioglitazone on diffusion tensor imaging indices in multiple sclerosis patients.

Pioglitazone is an FDA-approved peroxisome proliferator activated receptor gamma (PPARgamma) agonist. We tested the hypothesis that treatment with pioglitazone reduces new lesion development in patients with RRMS. Twenty-two patients were treated with pioglitazone or placebo and monitored by diffusion tensor imaging (DTI) at baseline and after 12 months. A negative correlation was found between the 1-year change in relative anisotropy (RA) and fluid attenuated inversion recovery (FLAIR) lesion burden in the pioglitazone group. Regions of interest (ROIs) having high ADC and low RA values at baseline had a significantly higher chance to develop into lesions in the placebo group than similar ROIs in the pioglitazone group. These findings suggest that baseline DTI parameters can provide a prognostic surrogate marker for lesions, and that pioglitazone can reduce conversion of normal appearing white matter to lesions.