Serum calcium level is associated with metabolic syndrome in the general population: FIN-D2D study

Background: The aim of this cross-sectional study was to examine the association between serum calcium and the components of metabolic syndrome (MetS). Methods: As a part of the national prevention program of diabetes in Finland (FIN-D2D), a randomly selected study population of 4500 middle-aged men and women were recruited from three central hospital district areas. Anthropometric measurements were performed by a trained nurse. An oral glucose tolerance test was performed and serum calcium and lipids were measured. We assessed current medications, physical activity, smoking, alcohol consumption, calcium intake, and vitamin D intake. The MetS was defined according to the criteria of the updated National Education Program. The study population consisted of 2896 individuals: 1396 men (62% of invited individuals) and 1500 women (66.7% of invited individuals). Results: The mean age was 60.3 +/- 8.3 years in men and 59.8 +/- 8.5 years in women. The prevalence of MetS was 50.7% in women and 55.8% in men. The prevalence of MetS and its components, except high-density lipoprotein (HDL)-cholesterol, increased linearly with increasing serum calcium (P < 0.001), even after adjustment for age, physical activity, alcohol, vitamin D intake, calcium intake, and smoking. The threshold value for serum calcium for MetS was 2.50 mmol/l in this population. The association of MetS with total serum calcium was similar even after exclusion of patients treated with hypertensive drugs. The drug treatments for hypertension, dyslipidemia, and diabetes increased in a similar pattern. Conclusions: Serum calcium level is associated with MetS and its components, except HDL-cholesterol.