Endocrine Abstracts

Introduction: The consequences of vitamin D deficiency are secondary hyperparathyroidism and bone loss, leading to osteoporosis and fractures, mineralization defects, which may lead to osteomalacia in the long term, and muscle weakness, causing falls and fractures.

Objectives: The aim of the research was to determine the frequency of vitamin D deficiency, secondary hyperparathyroidism and it’s influence on bone mineral density in people of different ages.

Methods: There were examined 683 patients aged 20–94 years. 25(OH)D and iPTH level was evaluated by electrochemiluminescence method (Elecsys 2010, Roche). Vitamin D deficiency was defined as a 25(OH)D below 20 ng/ml (50 nmol/l), and vitamin D insufficiency as a 25(OH)D of 21–29 ng/ml (52.5–72.5 nmol/l). Bone mineral density (BMD) was studied by X-ray densitometry ‘Prodigy’.

Results: Only 6.1% of people had normal level of vitamin D, vitamin D deficiency was recorded in 81.4% patients. In 16.8% the amount of 25(OH)D was below the minimal level that can machine determine. Significantly higher level of 25(OH)D recorded in summer months, and the lowest – in the winter-spring season. Secondary hyperparathyroidism diagnosed in 11.6% patients. It was found the negative correlation between the levels of 25(OH)D and parathyroid hormone (r=−0.16, P=0.0001). It was shown that only people with vitamin D deficiency have significant negative correlations between the level of parathyroid hormone and BMD at the neck and proximal femur (r=−0.14, P=0.005 and r=−0.13, P=0.04 respectively), upper and lower extremities (r=−0.11, P=0.02) and UD forearm (r=−0.11, P=0.03).

Conclusion: Deficiency of vitamin D leads the increasing of the level of parathyroid hormone, which decreasing BMD, mainly in areas of the skeleton composed of compact bone tissue.