English summary: Prevalence of vitamin D insufficiency in Finnish adult population

Background

Vitamin D status below optimal has been associated with several chronic diseases. However only a few studies have assessed the possible physical and life-style related confounding factors related to serum 25-hydroxyvitamin D [S-25(OH)D] levels. Our aim was to investigate the prevalence of vitamin D insufficiency in Finnish adult population, and to determine factors that are associated with S-25(OH)D levels.

Methods

A cross-sectional population-based survey (D2D) of the Development Programme for the Prevention and Care of Diabetes in Finland (Dehko) was carried out in 2007. 45-74 year-old participants were recruited from the population register. S-25(OH)D] was measured with chemiluminescent microparticle immunoassay. S-25(OH)D concentration lower than 50 nmol/l was considered as vitamin D insufficiency.

Results

The study comprised of 1348 men and 1474 women. Vitamin D insufficiency was more common among women (36.0 %) than men (30.6 %). S-25(OH)D concentrations correlated positively with age, physical activity and with the use of vitamin D containing supplements both in men and in women. In addition, in women S-25(OH)D concentrations correlated negatively with BMI. Vitamin D insufficiency was most common in women with BMI higher than 35 (56.5 %), and most uncommon in men who use vitamin D containing supplements (19.8 %).

Conclusions

Several factors associate with S-25(OH)D levels which should be considered in studies evaluating association of vitamin D with chronic diseases. In Finland, the risk of vitamin D insufficiency is particularly high in women at working age, who have a high BMI, whose physical activity is low, and who do not use vitamin D containing supplements.