To the Editor: Dr Nissen and colleagues1 reported that in patients with type 2 diabetes and coronary artery disease, treatment with pioglitazone resulted in a significantly lower rate of progression of coronary atherosclerosis compared with glimepiride. According to the authors, patients randomized to pioglitazone exhibited a lower rate of progression of coronary atherosclerosis across a wide array of prespecified and exploratory subgroups. Similar results by the same group and other researchers have been reported with statin treatment, in particular with rosuvastatin and atorvastatin.2,3 Given that statins are known to provide this type of benefit, a possible interference of statin exposure should have been taken into consideration in the study design, possibly stratifying treatment allocation on the basis of statin presence or absence.
Fresco C. Pioglitazone vs Glimepiride in the PERISCOPE Trial. JAMA. 2008;300(7):787-788. doi:10.1001/jama.300.7.787-a