Altered calcium homeostasis is correlated with the presence of metabolic syndrome and diabetes in middle-aged and elderly Korean subjects: the Chungju Metabolic Disease Cohort study (CMC study).

OBJECTIVE

To clarify the association of serum calcium level with metabolic syndrome (MetS) and diabetes in middle-aged and elderly Korean subjects.

DESIGN AND PATIENTS

We conducted a population-based, cross-sectional survey of 1329 participants aged over 40 years (median age 65.8) in a rural area of Chungju, Korea, in 2007.

MEASUREMENTS

Serum level of albumin, calcium, 25-hydroxy-vitamin D and intact parathyroid hormone were measured in a central laboratory.

RESULTS

The prevalence of MetS increased progressively with elevated serum albumin-corrected calcium levels (P<0.001 for trend). After adjusting for various covariates, subjects in the highest quintile group (2.45-2.99 mmol/L) compared with the lowest quintile group (2.05-2.24 mmol/L) of serum calcium levels had an odds ratio (OR) for having MetS of 3.11 (95% confidence intervals, CI, 1.95-4.97; P for trend<0.001). Excluding the subjects with hypocalcemia and hypercalcemia (n=1064) did not alter this significant association. After multiple adjustment, subjects with serum calcium levels in the fourth to fifth quintiles had a 2.0- to 3.0-fold increased OR of having diabetes (first quintile reference, fourth quintiles OR 2.38; 95% CI 1.32-4.28, fifth quintiles OR 3.32; 95% CI 1.87-5.88; P for trend<0.001).The associations of serum calcium levels with the incidences of MetS or diabetes were unchanged after adjustment for 25(OH)D and PTH levels.

CONCLUSIONS

Altered calcium homeostasis was associated with an increased risk of having MetS and diabetes in this demographic group.