my personal edition > diabetes > news


  E-Mail this DGDispatch to a colleague

DGDispatch

Higher Risk Patients Benefit More After Conversion from Rosiglitazone to Pioglitazone: Presented at AACE

By Mike Fillon

CHICAGO, I.L. -- May 3, 2006 -- A new study shows that conversion from rosiglitazone to pioglitazone while maintaining statin therapy, improves the lipid profiles in patients with type 2 diabetes, according to results of a study presented here at the American Association of Clinical Endocrinologists (AACE) annual meeting.

In this study, patients with type 2 diabetes underwent 1 week of screening and 17 weeks of treatment with 30 mg pioglitazone once daily after conversion from rosiglitazone. All patients continued stable statin or other lipid-lowering therapy. For this analysis, patients were separated into 2 groups based on their low-density lipoprotein (LDL) particle size at baseline:
· Pattern A=20.6-23.00 nm; large buoyant particles
· Pattern B=18.0-20.5 nm; small dense particles

Lead researcher Robert Spanheimer, MD, medical director for diabetes and metabolism, Takeda Pharmaceuticals North America, Lincolnshire, Illinois, United States, said patients with type 2 diabetes, who are at increased risk for cardiovascular disease, also have a greater incidence of the pattern B LDL phenotype, which further increases their risk.

The primary outcome variable of the multicenter, single-arm, open-label study was change in triglyceride level after conversion from rosiglitazone to pioglitazone.

A total of 305 subjects ranging in age from 18 to 70 with type 2 diabetes were enrolled in the study. Of these, 94 were identified as having pattern A and 201 had pattern B LDL particles.

According to Dr. Spanheimer, patients with type 2 diabetes often have multiple abnormalities in their lipid profile, including altered phenotype, which may contribute to accelerated atherosclerosis. "Also, a greater incidence of the pattern B phenotype is found in diabetic compared to non-diabetic patients and is associated with increased risk for cardiovascular disease," Dr. Spanheimer said.

In the study, patients with pattern A LDL showed a slight mean decrease in glycosylated hemoglobin A1c (-0.07%) whereas patients with pattern B LDL showed a slight mean increase (+0.08%) from baseline to week 17. Patients with either phenotype showed improvement in overall LDL concentrations (pattern A: -90.8 nmol/L, P =.004; pattern B: -235.7 nmol/L, P <.001).

Patients with pattern B LDL showed both a significant mean decrease in small LDL concentration (-312.5 nmol/L, P<.001) and a significant mean increase in large LDL concentration (+84.3 nmol/L, P<.001). On the other hand, patients with pattern A LDL showed a significant mean decrease in large LDL particle concentration (-60.3 nmol/L, P =.001) and a slight decrease in small LDL particle concentration.

Further, patients with pattern B LDL showed a significant mean increase in LDL particle diameter (+0.33 nm, P<.001), whereas this parameter did not change among patients with pattern A LDL.

Dr. Spanheimer said higher risk patients with type 2 diabetes (pattern B LDL) achieve greater improvements in lipid profiles than lower risk patients (pattern A LDL) including a significant reduction in LDL particle concentration and a significant increase in LDL particle size, after conversion from rosiglitazone to pioglitazone while maintaining stable statin therapy.

Even greater improvements in triglycerides, total cholesterol and LDL particle size and concentrations were seen among higher risk patients compared to lower risk patients, Dr. Spanheimer said.

Pioglitazone and rosiglitazone are insulin sensitizers belonging to the thiazolidinedione class of oral anti-diabetic medications. They directly target insulin resistance; a condition in which the body does not efficiently use the insulin it produces to control blood glucose levels. As an adjunct to diet and exercise, they are used for treating type 2 diabetes as monotherapy to lower blood glucose and in combination therapy with insulin, sulfonylureas or metformin.


[Presentation title: Change in Lipid Profile in Patients Presenting with Small Dense DL Before and After Conversion from Rosiglitazone to Pioglitazone. Abstract 292]

E-Mail this DGDispatch to a colleague

To print, use this version