TNF-alpha gene polymorphism and TNF-alpha levels in obese Asian Indians with obstructive sleep apnea

Background: Obstructive steep apnea (OSA) is emerging as a significant disorder in India. Tumor necrosis factor-alpha (TNF alpha) is an important marker of inflammation. Recent data indicate that inflammation may be an important correlate of OSA. The relationships of OSA with TNF alpha. levels and TNF alpha gene promoter polymorphism (-308G/A) have not been investigated in obese Asian Indians with OSA. Objective: To took for the correlation if any, between TNFa gene promoter polymorphism (-308G/A) in obese Asian Indians with and without OSA and correlation of TNF alpha levels with severity of OSA. Methods and results: We studied 207 obese (BMI > 25 kg/m(2)) subjects; 104 with OSA and 103 without OSA. Both groups were matched for age, body mass index (BMI) and percentage body fat (%BF). Measurements included anthropometric and biochemical (fasting blood glucose, lipid profile and serum TNF alpha levels) parameters and TNF alpha gene promoter polymorphism (-308G/A). The frequency of '-308A' allele in TNF alpha gene was significantly higher in obese subjects with OSA (28.8%; 60/208), when compared with obese subjects without OSA (12.6%; 26/206, p = 0.001). Serum TNF alpha levels were significantly higher in obese subjects with OSA [(3.6 +/- 0.8)pg/ml], when compared with obese subjects without OSA [(3.3 +/- 0.6)pg/ml, p = 0.009]. Conclusions: Frequency of TNF alpha (-308A) allele and serum TNF alpha level was significantly higher in obese Asian Indians with OSA. (C) 2008 Elsevier Ltd. All rights reserved.