Cited 91 times since 2008 (5.7 per year) source: EuropePMC Chest, Volume 134, Issue 5, 18 3 2008, Pages 925-930 The obesity paradox in patients with peripheral arterial disease. Galal W, van Gestel YRBM, Hoeks SE, Sin DD, Winkel TA, Bax JJ, Verhagen H, Awara AMM, Klein J, van Domburg RT, Poldermans D
Background
Cardiac events are the predominant cause of late mortality in patients with peripheral arterial disease (PAD). In these patients, mortality decreases with increasing body mass index (BMI). COPD is identified as a cardiac risk factor, which preferentially affects underweight individuals. Whether or not COPD explains the obesity paradox in PAD patients is unknown.
Methods
We studied 2,392 patients who underwent major vascular surgery at one teaching institution. Patients were classified according to COPD status and BMIs (ie, underweight, normal, overweight, and obese), and the relationship between these variables and all-cause mortality was determined using a Cox regression analysis. The median follow-up period was 4.37 years (interquartile range, 1.98 to 8.47 years).
Results
The overall mortality rates among underweight, normal, overweight, and obese patients were 54%, 50%, 40%, and 31%, respectively (p < 0.001). The distribution of COPD severity classes showed an increased prevalence of moderate-to-severe COPD in underweight patients. In the entire population, BMI (continuous) was associated with increased mortality (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.94 to 0.98). In addition, patients who were classified as being underweight were at increased risk for mortality (HR, 1.42; 95% CI, 1.00 to 2.01). However, after adjusting for COPD severity the relationship was no longer significant (HR, 1.29; 95% CI, 0.91 to 1.93).
Conclusions
The excess mortality among underweight patients was largely explained by the overrepresentation of individuals with moderate-to-severe COPD. COPD may in part explain the "obesity paradox" in the PAD population.
