Extremely obese patients who underwent percutaneous coronary intervention (PCI) were younger and had less bleeding when compared to normal weight patients, according to a study published in a special issue of the Journal of the American College of Cardiology (JACC) focused on cardiometabolic syndrome.

The study, based on 1,221,086 patients in the ACC's NCDR® CathPCI Registry® who underwent radial or femoral PCI and were discharged between July 2009 and June 2011, found lower median age (60 vs. 69), higher female to male ratio, higher proportion of African Americans, and markedly higher prevalence of diabetes mellitus, hypertension and Hyperlipidemia in extremely obese patients (BMI≥40 kg/m2).

In addition, extremely obese patients had lower unadjusted mortality (1.2 percent vs. 2.0 percent); however, after multivariable adjustment, for those patients with STEMI, extreme obesity was independently associated with a higher risk of in-hospital mortality (OR = 1.22; 95 percent CI 1.08-1.39). Data also showed extreme obesity to be independently associated with less in-hospital bleeding complications. According to the investigators, this difference "may reflect under-dosing of anticoagulants, or higher use of closure devices or transradial access."

While study investigators noted a history of PCI was more common in the extremely obese group, cerebrovascular and peripheral vascular diseases were more common in normal weight patients. "Access site had no effect on bleeding or outcome," the investigators said.

These findings are important given that the number of extremely obese patients undergoing PCI is increasing, according to data from a separate paper published in the special JACC issue. In looking at 227,044 patients undergoing PCI and enrolled in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) registry from 1998-2009, study investigators found the proportion of morbidly obese patients undergoing PCI increased from 4.38 percent in 1998 to 8.36 percent in 2009. Compared with overweight patients (BMI 25-30 kg/m²), extremely obese patients had significantly increased vascular complications, contrast- induced nephropathy, nephropathy requiring dialysis and mortality.

"These epidemiological changes have important implications for technical considerations of cardiac catheterization, design of the catheterization lab to accommodate these patients and most importantly for societal effort toward prevention of obesity," the study authors warn.

Keywords: Hospital Mortality, Hyperlipidemias, Overweight, Cardiac Catheterization, Blue Cross Blue Shield Insurance Plans, Peripheral Vascular Diseases, Percutaneous Coronary Intervention, Prevalence, Renal Dialysis, Body Mass Index, Obesity, Morbid, Hypertension, United States, Diabetes Mellitus