Seasonal Variation in Vitamin D in Association with Age, Inflammatory Cytokines, Anthropometric Parameters, and Lifestyle Factors in Older Adults

الملخص EN

Vitamin D deficiency is present even in sunny regions.

Ageing decreases pre-vitamin D production in the skin and is associated with altered cytokine profile.

We performed a multivariate analysis considering lifestyle factors, anthropometric, and inflammatory markers according to seasonal variation in Mexican healthy older adults.

The same cohort was followed during 12 months.

Vitamin D deficiency/insufficiency was found in 91.3% of the subjects despite living in appropriate latitude (25°40′0″N).

25(OH)D levels remained below <30 ng/mL through all seasons.

Vitamin D deficiency did not correlate to sun exposure or dietary intake.

Gender was the strongest associated factor, explaining a variance of 20%.

Waist circumference (WC) greater than 88 cm was a risk factor for vitamin D deficiency.

Age (>74 years) combined with WC (>88 cm) and BMI (>32.7) showed a high probability (90%) of vitamin D deficiency.

Remarkably, an increase in one centimeter in WC decreased 25(OH)D by 0.176 ng/mL, while an increase in one point BMI decreased 25(OH)D by 0.534 ng/mL.

A cutoff point of 74 years of age determined probability of vitamin D hipovitaminosis.

Vitamin D deficiency was correlated with TNF-α serum levels, possibly increasing the susceptibility of older adults to a proinflammatory state and its related diseases.