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Published on: December 9, 2015
Seasonal variation in 25-hydroxyvitamin D and parathyroid hormone concentrations in healthy elderly people
V Hegarty1, P Woodhouse, K T Khaw
1Clinical Gerontology Unit, University of Cambridge, Addenbrooke's Hospital.
Abstract:
Seasonal variation in serum 25-hydroxyvitamin D and parathyroid hormone concentration was examined longitudinally in 96 community-dwelling men and women aged 65-74 years. Mean 25-hydroxyvitamin D concentration was lowest in winter (22.7 mmol/l) and highest in summer (35.4 mmol/l); mean parathyroid hormone concentration was highest in winter (3.55 pmol/l) and lowest in summer (3.24 pmol/l): these seasonal variations were highly significant (p < 0.0001). Parathyroid hormone concentrations were inversely related to 25-hydroxyvitamin D concentrations (p < 0.0001). Seasonal variation of 25-hydroxyvitamin D and parathyroid hormone concentration is marked in older healthy adults in Britain. Even in summer, mean 25-hydroxyvitamin D concentrations are low; maintaining more optimal vitamin D levels in the general population may have clinical and public health benefits.
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