NEW YORK (Reuters Health) – A body mass index that falls outside the normal range is associated with an increased risk of bleeding and death after percutaneous coronary intervention (PCI), new research reveals.

While obesity is a well known risk factor for the development of heart disease, some studies have suggested that moderate obesity may paradoxically improve PCI outcomes. By contrast, research has generally shown that low BMIs increase the risk of poor outcomes.

To better understand the nature of the relationship, Dr. Jonathan Byrne, from King’s College Hospital, London, and colleagues analyzed data from 38,346 consecutive PCI patients who were entered in the British Columbia Cardiac Registry. The findings are reported in the American Journal of Cardiology for February 15.

Mortality was increased with both high and low BMIs, the report indicates (p < 0.0001). This was particularly apparent for individuals who were underweight (BMI of <18.5, OR=1.98) and morbidly obese (BMI of 40 or higher, OR=1.61). This U-shaped curve was also seen regarding the odds of periprocedural transfusion, which increased the risk of adverse outcomes by 2.86-fold (p < 0.0001). Female gender was also identified as a risk factor for bleeding, and emergent PCI and femoral access were linked to adverse outcomes. “Although the precise reasons for the bimodal distribution of both bleeding and outcome at BMI extremes remain unclear, it is most likely that co-morbidity drives bleeding and mortality in the underweight subgroup, whereas these events are a consequence of the increased body mass in the very obese,” the authors state. Reference:
Am J Cardiol 2009;103:507-511.