Institution: | 1.Bone Metabolic Unit, Department of Internal Medicine,Hospital Universitario Marqués de Valdecilla,Santander,Spain;2.IDIVAL, Red Temática de Investigación Cooperativa en Envejecimiento y Fragilidad (RETICEF),University of Cantabria,Santander,Spain;3.Centro de Salud Camargo,Santander,Spain;4.Epidemiology Unit, Medical School,University of Cantabria, Centro de Investigación Biomédica en Red Epidemiología y Salud Pública (CIBERESP),Santander,Spain |
Abstract: | SummaryVitamin D insufficiency is very common among Spanish community-dwelling adult subjects. A threshold of serum 25(OH)D around 30 ng/ml would be necessary for the prevention of secondary hyperparathyroidism and hip bone loss in our population, regardless of the dairy calcium ingestion.IntroductionThis study aims to assess 25-hydroxyvitamin D—25(OH)D—status in Spanish adult subjects and to analyze its relationships with serum PTH levels, calcium intake, and bone mineral density (BMD).MethodsA total of 1811 individuals (1154 postmenopausal women and 657 men) aged 44–93 years participated in the study. Serum 25(OH)D, intact parathyroid hormone (PTH), aminoterminal propeptide of type I collagen (P1NP), and C-terminal telopeptide of type I collagen (β-CTX) levels were measured by electrochemiluminescence. BMD was determined by dual x-ray absorptiometry (DXA) at lumbar spine, femoral neck, and total hip.ResultsSerum 25(OH)D levels were below 10, 20, and 30 ng/ml in 5, 40, and 83 % of participants, respectively. There was a significant seasonal difference in mean serum 25(OH)D, with higher levels in summer–autumn. In multivariate analysis, 25(OH)D levels were negatively correlated with age, serum PTH and creatinine, body mass index, smoking, alcohol intake, and a number of chronic diseases, but positively with dairy calcium intake. The magnitude of the difference in serum PTH according to 25(OH)D quartiles was not influenced by calcium intake. A threshold of serum 25(OH)D around 30 ng/ml was observed for serum PTH and hip BMD.ConclusionsVitamin D insufficiency is very common among Spanish community-dwelling adult subjects. A threshold of serum 25(OH)D around 30 ng/ml would be necessary for the prevention of secondary hyperparathyroidism and hip bone loss in our population, regardless of the dairy calcium ingestion. Programs to improve vitamin D status may be required in our country. |