High BMI linked to lower mortality after PCI, more metabolic abnormalities
MedWire News: Study results indicate that patients with a high body mass index (BMI) have low rates of all-cause mortality after percutaneous coronary intervention (PCI).
However, patients with higher BMIs were more likely to have an increased number of metabolic abnormalities than their normal-weight peers, and this was associated with a greater risk for all-cause mortality, the authors note in the American Journal of Cardiology.
"The lower rate of mortality in obese patients, who on average have more metabolic abnormalities, seems counterintuitive," remark Michael Farkouh (Mount Sinai School of Medicine, New York, USA) and colleagues.
They suggest that obese patients are more likely to be aggressively screened by physicians - because higher BMI is considered a risk factor for developing metabolic abnormalities - and this may lead to an earlier recognition of disease states among these patients.
The researchers categorized 9673 PCI patients by BMI (18.5-24.9, 25-29.9, 30-34.9, and ≥35 kg/m2) and then assessed the prevalence of the following metabolic abnormalities: C-reactive protein ≥2 mg/l, fasting glucose ≥100 mg/dl, hypertension, serum triglycerides ≥150 mg/dl (1.69 mmol/l), or high-density lipoprotein cholesterol <40 mg/dl (1.04 mmol/l).
Over the 3-year follow-up period they found that patients with a BMI of 18.5-24.9 kg/m2 had significantly higher rates of all-cause mortality after PCI compared with patients with BMIs of 25-29.9, 30-34.9, and ≥35 kg/m2, at 55.5 versus 33.7, 28.3, and 33.8 deaths per 1000 person-years, respectively.
However, patients with a BMI above 35 kg/m2 were more likely to have more metabolic abnormalities than patients with lower BMIs, despite their lower risk for all-cause mortality. Four or five metabolic abnormalities were present in 31% of patients with a BMI ≥35 kg/m2, compared with 12%, 18%, and 24%, of patients with BMIs of 18.5-24.9, 25-29.9, and 30-34.9 kg/m2, respectively.
Furthermore, in patients with BMIs of 30-34.9 kg/m2, risk for all-cause mortality associated with two, three, or four to five metabolic abnormalities was 1.31-, 1.42-, and 2.39-fold higher than those who had none or one metabolic abnormality. For patients with a BMI above 35 kg/m2, the mortality risks were increased a corresponding 1.94-, 1.44-, and 2.17-fold.
Farkouh et al add that associations between more metabolic abnormalities and an increased risk for mortality were consistent across all BMI categories.
The researchers conclude that the benefits of aggressive periprocedural management of metabolic abnormalities before an elective PCI deserves further study.
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By Nikki Withers