Vitamin D deficiency during winter months among an adult, predominantly urban, population in Northern Poland.

Abstract

Vitamin D is vital in the regulation of the calcium-phosphate metabolism, has a direct impact on the musculoskeletal system, and also affects numerous other systems. Widespread vitamin D deficiency and its detrimental effect on health have been reported globally. Data concerning vitamin D status in Polish adult population is scarce. Ambulatory patients of an outpatient clinic in Gdańsk were included in the study. Serum concentrations of 25(OH) D, parathyroid hormone (PTH), alkaline phosphatase (ALP), calcium and phosphorus were determined. In a questionnaire declared UVB exposure, dietary vitamin D and calcium intake, and health status of the subjects were assessed. Non- and parametric tests, logistic regression and population attributable risk were applied in data analysis. 448 adults were examined from February to mid-April 2012, 305 women and 143 men, aged 19 to 86 (mean 46.3 ± 14.9 years). Mean 25-hydroxyvitamin D concentration was 14.3 ± 6.6 ng/mL. 84.4% of subjects were vitamin D deficient (25(OH)D < 20 ng/mL); 13.2% presented insufficient (20-30 ng/mL), and 2.5% (or 11 subjects) sufficient 25(OH)D concentrations. Significantly higher 25(OH)D concentrations were found in subjects who reported more UVB exposure, supplemented vitamin D orally and those who declared more physical activity. 21% of subjects had elevated serum PTH concentration (i.e. > 62 pg/mL); mean parathormone was 48.6 ± 25.2 pg/mL. A linear correlation was found between the logarithm of PTH and logarithm of 25(OH)D concentrations (r = -0.21, p < 0.001). Results obtained here demonstrate the necessity of implementing a monitoring and prophylaxis programme of vitamin D deficiency in Poland.