Community-based study on summer–winter differences of component of metabolic syndrome in Kinmen, Taiwan

Abstract

Background. A community-based study was conducted to investigate summer–winter differences of component of metabolic syndrome in Kinmen, Taiwan. Methods. A total of 8251 residents aged 40 and over were enrolled in the mass survey in Kinmen. They were investigated while on summer (July and August) and winter vacation (January and February) during 2000–2003. Demographics, physical examination findings, lifestyle variables and biochemical data were collected. Results. After controlling for age, body mass index, diet, lifestyle and other risk factors for component of metabolic syndrome, there were independent and significant relationships between summer–winter difference and component of metabolic syndrome. Winter season was positively correlated with blood pressure, fasting plasma glucose level, high-density lipoprotein-cholesterol (HDL-C) and waist circumference, but was negatively associated with fasting triglycerides and metabolic syndrome. Conclusions. Summer season is positively associated with hypertriglyceridemia, low HDL-C and metabolic syndrome. These findings imply that cross-sectional, experimental and cohort studies of component of metabolic syndrome or metabolic syndrome should take season into account as possible confounding effects.