Background There is a high prevalence of hypovitaminosis D (HD) in the UAE population and this may be complicated by secondary hyperparathyroidism (HD-SHPT).The latter has a pivotal role in the pathogenesis of low bone mineral disease.

Objectives To investigate the relationship between these conditions and the bone mineral density among residents of Abu Dhabi (UAE).

Methods 117 adults, predominately (80.5%) Arab individuals (age 15-76 years) with hypovitaminosis D were selected for the study, of whom 25 (21.5%) were deficient (HD), and 78 (66.5%) also had secondary hyperparathyroidism (HD-SHPT). Both T and Z scores were used in the evaluation of dual energy x ray absorptiometry (DXA) findings. Data of patients with chronic renal failure (CRF) and autoimmune disordersand recent or current therapy with corticosteroids (CS) were excluded.

Results The mean age, gender distribution, BMI, mean of 25-OH D and the mean of alkaline phosphatase (AP) in patients with HD-SHPT were not significantly different to others with normal PTH. Both T and Z scores also failed to show any significant differences in normal outcome, osteopenia & osteoporosis (47.5% vs. 41% p=0.55, 33.5% vs. 43.5% p=0.10 and 19% vs.15% p=0.79) in the two groups respectively. However, a lower mean of serum calcium yet within eucalcemia was observed in HD-STHP (9.39±0.395 vs.9.59±0.355 mg/dl, p=0.025). The range in these two groups was (8.58-10.6 and 8.89-10.4mg/dl) respectively. The mean of each of the age, 25-OH D, calcium and AP in osteoporotic patients of both groups were not different also, p=NS.

Conclusions Secondary hyperparathyroidism is not always a prerequisite for the development of low bone mineral density in patients with hypovitaminosis D. The low bone mineral density in the others with normal or low PTH invites further investigations and understanding.

Disclosure of Interest None declared