Bone Abstracts

Purpose: To evaluate whether calcium and vitamin D intake is associated with 25-hydroxyvitamin D (25(OH)D) and parathyroid hormone (PTH) serum concentrations or is associated with either the phalangeal dual energy X-ray absorptiometry (pDXA) or the quantitative bone ultrasound (QUS) at the phalanges and the calcaneus in independent elderly men from southwestern Spain.

Methods: Serum PTH and 25(OH)D were measured in 199 healthy elderly men (mean age: 73.31±5.10 year). Food intake was quantified using a dietetic scale on the basis of current 7-day dietary records. Both pDXA and QUS at the phalanges and the calcaneus were assessed.

Results: Participants with 25(OH)D levels ≥30 ng/ml and a calcium intake of 800–1200 mg/day exhibited the lowest PTH levels (41.49±16.72 ng/ml). The highest PTH levels (75.60 ng/ml ±14.16) were observed in the <30 ng/ml group 25(OH)D with a calcium intake >1200 mg/day. No significant differences in the serum PTH levels based on the serum 25(OH)D levels were observed among participants with a calcium intake of 800–1200 mg/day. Serum PTH was inversely correlated with serum 25(OH)D in the entire patient sample (r=−0.288, P=0.019). No differences in any of the three densitometry techniques were observed between any of the age groups in the 800–1200 and >1200 mg/day calcium intake groups.

Conclusions: PTH levels correlate negatively with serum 25(OH)D levels, and neither calcium nor vitamin D intake exert a strong influence on either of the two parameters.