నైరూప్య

Seasonal variation in status of Vitamin-D, serum bone profile and thyroid function in adult population of Saudi Arabia

Sadia Arjumand, Hajera Tabassum, Mir Naiman Ali, Noura Al-Jameil

Vitamin D plays a critical role in bone metabolism and many cellular and immunological processes. Serum 25-hydroxyvitamin D3 [25(OH)D₃] is produced in the skin in response to exposure to ultraviolet radiation, and is a good indicator of vitamin D status. The aim of this study was to determine summer/ winter differences in serum 25(OH)D₃ and Parathyroid Hormone (PTH) in Saudi pre and postmenopausal women and in adult males. We focused on the interaction of Vitamin D with other biochemical markers of bone metabolism like PTH, ALP and Calcium and how it varies on seasonal changes. The subjects were 115 Saudi adults divided into three groups; 31 males, 42 premenopausal and 42 postmenopausal women. They were medically examined twice, in summer (April-July 2014) and winter (December 2014-February 2015) months. 25(OH)D₃, PTH, TSH, ALP, calcium and inorganic phosphorus were estimated and found that status of vitamin D varies significantly with seasonal changes (highest being in summer), age and also with sex. Seasonal differences in the 25(OH)D₃ concentrations in these subjects appeared to reflect ability to produce 25(OH)D₃ photochemically in the skin. In addition to vitamin D, levels of biochemical markers exhibited summer/winter differences and also varied among the pre and postmenopausal women and were statistically different from males.