Abstract
BACKGROUND: Several cross-sectional studies have reported risk factors for metabolic syndrome (MetS). However, these studies did not focus on sex differences in middle-aged and senior populations or employ a longitudinal design. These study design differences are important, as there are sex differences in lifestyle habits associated with MetS, and middle-aged and senior individuals have increased MetS susceptibility. Therefore, the purpose of this study was to examine whether sex differences influenced MetS risk over a ten-year follow-up period among middle-aged and senior hospital employees. METHODS: This population-based and prospective cohort study enrolled 565 participants who did not have MetS in 2012 for a ten-year repeated-measurement analysis. Data were retrieved from the hospital's Health Management Information System. Analyses included Student's t tests, χ(2) tests and Cox regression. P < 0.05 indicated statistical significance. RESULTS: Male middle-aged and senior hospital employees had an elevated MetS risk (hazard ratio (HR) = 1.936, p < 0.001). Men with more than four family history risk factors had an increased risk of MetS (HR = 1.969, p = 0.010). Women who worked shift duty (HR = 1.326, p = 0.020), had more than two chronic diseases (HR = 1.513, p = 0.012), had three family history risk factors (HR = 1.623, p = 0.010), or chewed betel nuts (HR = 9.710, p = 0.002) had an increased risk of MetS. CONCLUSIONS: The longitudinal design of our study improves the understanding of sex differences in MetS risk factors in middle-aged and senior adults. A significantly elevated risk of MetS over the ten-year follow-up period was associated with male sex, shift work, the number of chronic diseases, the number of family history risk factors, and betel nut chewing. Women who chewed betel nuts had an especially increased risk of MetS. Our study indicates that population-specific studies are important for the identification of subgroups susceptible to MetS and for the implementation of hospital-based strategies.