Abstract
Objective: To evaluate vitamin D status and its implications on bone metabolism in Ankara, Turkey.
Materials and Methods: A population-based study was designed. Vitamin D status was evaluated in both elderly (≥65 years old) and reproductive-aged (20-40 years old) female population living in the same area. All subjects were given questionnaires asking for sunlight exposure and skin covering scores in order to estimate sunlight utilization score (SUS). Their serum 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH), alkaline phosphatase (ALP) Calcium (Ca), Phoshorus (P) levels were measured. The bone mineral density was determined by means of calcaneal quantitative ultrasound (QUS).
Results: Serum 25(OH)D levels were similar in both the elderly (n=251) and the younger (n=301) groups [16.8 (11.5-26.5) vs 18.6 (13.2-26.4) ng/ml]. Vitamin D status was sufficient in only 21.3% of the elderly, and in 18.3% of the younger group (p: 0.153). However, both secondary hyperparathyroidism (28.7 vs 15.3%, p<0.001) and osteopenia, determined by quantitative ultrasound measurements (46.9 vs 7.0%, p<0.001), were more prevalent in the elderly women compared to the younger females.
Conclusions: Since it has a high prevalence of approximatelyz 80% in both the reproductive-aged and the elderly women, vitamin D insufficiency seems to be a public health problem in Ankara, Turkey. Insufficient vitamin D status beginning at early adulthood may predispose to secondary hyperparathyroidism that is, at least, contributing to bone loss observed during postmenopausal period.