THE ASSOCIATION OF BODY MASS INDEX AND LEPTIN WITH SERUM AND URINE LEUKOTRIENE LEVELS IN MODERATE TO SEVERE ASTHMATIC ADULTS AND NONASTHMATIC CONTROLS.

Abstract

Introduction Obese asthmatics appear to benefit more from antileukotriene drugs when compared with leaner asthmatics. However, it is unknown whether leukotriene (LT) levels are associated with body mass index (BMI) or leptin in these patients. Objective Describe the association of BMI and leptin with serum and urine leukotriene levels in asthmatics and nonasthmatic adults. Methods Moderate to severe asthmatics and nonasthmatic controls were invited to participate. All asthmatics were free from an exacerbation, were current nonsmokers, had an FEV1/FVC > 0.70, and were on inhaled corticosteroids. Participants provided urine samples for urinary LTE4 and plasma samples for LTB4, LTE4, and adipokines. All subjects also performed spirometry and exhaled nitric oxide (NO). Results A total of 65 asthmatics and 43 controls participated in the study. The average BMI was 32 (95% CI 31-35) in asthmatic subjects and 31 (29-33) in controls. A total of 54% of asthmatics were taking monteleukast. In asthmatics, the levels of plasma LTB4, LTE4, und urinary LTE4 (pg/mL) were 106 (95% CI 94-118), 620 (546-694), and 1,077 (846-1,309) respectively, whereas in controls these were 102 (80-125), 625 (537-714), and 1,050 (876-1,225). These levels were not statistically different. Plasma LTE4 levels were marginally lower in obese asthmatics compared with asthmatics with normal BMI (p = .06). Urinary LTE4 was also associated with increased exhaled isoprostane levels, independent of BMI (p Conclusions There were no consistent associations between BMI and leptin with leukotriene levels. Urinary LTE4 does appear to be associated with airway oxidation in asthmatics, independent of BMI.