ECE2011 Poster Presentations Bone/calcium/Vitamin D (58 abstracts)
1Hospital Carlos Haya, Malaga, Spain; 2Hospital Central de Asturias, Oviedo, Spain.
Background: Vitamin D deficiency is common worldwide. No homogenous reference values have yet been established and no studies of values have been done in Spain involving a large number of participants.
Objective: To study the population concentrations of vitamin D in a representative sample of the Spanish population.
Subjects/methods: The study involved two cohorts from Spain, the Asturias Study and the Pizarra Study, which are two prospective, population-based studies involving 2260 participants. In 1262 subjects (age: 2083 years) we studied 25-hydroxyvitamin D, intact parathyroid hormone (iPTH), calcium, phosphorus and creatinine.
Results: The median population values of 25-hydroxyvitamin D and iPTH were 22.46 ng/ml and 42.29 pg/ml respectively. The values of 25-hydroxyvitamin D were significantly higher in summer and correlated with age (β=−0.05±0.01, P<0.0001), creatinine (β=6.42±1.17, P<0.0001), and iPTH (−0.07±0.01, P<0.0001), but not with calcium, phosphorus or sex. The increase in iPTH with age was seen whatever the values of 25-hydroxyvitamin D, and was greater in the older persons. The concentration of iPTH rose continuously with effect from 25-hydroxyvitamin D values below ≈30 ng/ml. Values above ≈35 ng/ml were associated with a significantly lower concentration of iPTH.
Conclusions: One third (33.9%) of the Spanish population may be at risk for Vitamin D deficiency. 25-hydroxyvitamin D values above 30 ng/ml can safely discard hyper PTH. The increase in iPTH concentration is greater in older persons for similar values of 25-hydroxyvitamin D.