Plasma 1,25(OH)2D linked to big bellies in healthy, sedentary adults

Plasma levels of 1,25-dihydroxyvitamin D (1,25[OH]₂D) are unrelated to insulin resistance or cardiometabolic risk among healthy sedentary adults, a recent study has found. However, 1,25(OH)₂D may be an inverse predictor of central adiposity.

The cross-sectional study included 73 adults (mean age 54±5 years, 53 percent women) for whom a sex-specific cardiometabolic risk score (MetScore) was calculated using parameters such as waist circumference, blood pressure, and blood lipid profile. Plasma levels of 1,25(OH)₂D were measured using an immunochemiluminometric analyser.

Simple linear association revealed no significant association between 1,25(OH)₂D plasma levels and MetScore (β, 0.037; p=0.77). The same was true for insulin sensitivity as measured by the quantitative insulin sensitivity check index (QUICKI; β, 0.011; p=0.93) and for insulin resistance as measured by the homeostasis model for insulin resistance index (HOMA-IR; β, 0.005; p=0.97).

Further adjustment for age, sex, body mass index, and/or fat mass index did not alter the principal findings, such that MetScore, QUICKI, and HOMA-IR all remained unrelated to 1,25(OH)₂D levels.

However, looking at the individual cardiometabolic risk factors, 1,25(OH)2D was found to be significantly correlated with waist circumference (β, –0.303; p=0.01) even after controlling for confounders. Unadjusted associations were also reported for cholesterol and diastolic blood pressure, though these interactions were attenuated after adjustments.

“These results have important clinical implications since they suggest that 1,25(OH)₂D seems to be related to central adiposity in healthy individuals with normal values of these physiological parameters,” but not with other key cardiometabolic risk factors, the researchers said.