Introduction: The metabolic syndrome (MS) includes a clustering of metabolic derangements and low testosterone levels have been shown to be associated with both components of MS and MS per se. In this study we explored the relationship between androgen receptor (AR) CAG repeat length polymorphism and MS in a Korean male population.
Materials and methods: The association between AR CAG repeat length polymorphism and MS was analyzed in 144 Korean men (40-80 years old). MS was diagnosed according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP) criteria (any three or more of the following components were present: abdominal obesity (WC >102 cm), triglycerides >150 mg/dL (>1.7 mmol/L), HDL cholesterol <40 mg/dL (<1.04 mmol/L), fasting glucose >110 mg/dL (>6.1 mmol/L), or blood pressure of >130/85 mmHg). AR CAG repeat length polymorphism was determined by microsatellite fragment sizing and association with clinical factors (MS, age, height, weight, BMI, waist circumference, FBS, total cholesterol, HDL, LDL, triglyceride, HbA1c, sex hormone binding globulin) were analyzed.
Results: Mean age was 56.6±8.4 years. Mean AR CAG repeat length and serum testosterone levels were 20.74±12.5 and 5.5±1.7 ng/mL respectively. Twelve men with hypogonadism (serum testosterone level lower than 3.5 ng/mL) showed relatively short AR CAG repeat length compared with men with normal serum testosterone level (18.33 vs. 20.95, P=0.48). Long AR CAG repeat length is associated with an increase in LDL, triglyceride, and HbAc1 while showing negative correlation with HDL and total cholesterol. Total 113 men had at least one component of MS and 27 men were diagnosed with MS (more than three components). Men with MS showed relatively longer AR CAG repeat length compared with men without MS (23.3 vs. 19.7, P=0.14). Hypogonadal men showed relatively high risk of MS (OD: 1.656, CI: 0.409-6.709) compared with eugonadal men and in cross-sectional analyses, men with AR CAG repeat length less than 21 combined with hypogonadism showed more increased risk of MS (OR: 2.074, CI: 0.872-4.931).
Conclusions: In conclusion, AR CAG repeat length and hypogonadism seem to be associated with increased risk of MS in Korean male.
