Associations of immunological factors with metabolic syndrome and its characteristic elements in Chinese centenarians

BACKGROUND: Metabolic syndrome (MetS) has an increased prevalence (approximately 20–25% of the adult population) all over the world. Immunological function is significantly associated with the development of MetS, and MetS is beginning to be considered as a chronic immune-related disease. The present study addressed on the associations of immunological factors with MetS and its characteristic elements in Chinese centenarians. METHODS: Hainan is a longevity region with the highest population density of centenarians in China. The China Hainan Centenarian Cohort Study has a considerable sample size, and provides a significant population-based sample of centenarians. Home interview, physical examination and blood analysis were conducted following standard procedures. RESULTS: All centenarians had a median age of 102 (100–115) years, and the proportion of females was 80.8%. The proportion of centenarians with MetS was 16.0% (135 centenarians). Abdominal obesity, hypertension, dyslipidemia and diabetes mellitus had a prevalence of 26.4% (223 centenarians), 73.7% (623 centenarians), 40.4% (341 centenarians) and 10.7% (90 centenarians), respectively. In Logistic regression analyses, MetS was significantly associated with immunoglobulin E and complement C3 levels (P < 0.05 for all). Abdominal obesity was significantly associated with immunoglobulin E and complement C3 levels (P < 0.05 for all). CONCLUSIONS: The present study provides epidemiological evidence that MetS has significant associations with immunoglobulin E and complement C3 levels, and demonstrates that abdominal obesity is significantly associated with immunoglobulin E and complement C3 levels in Chinese centenarians.