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Vitamin D deficiency in Spain: a population-based cohort study.
I González-Molero1, S Morcillo, S Valdés
1Servicio de Endocrinología y Nutrición, Hospital Regional Universitario Carlos Haya, Málaga, Spain. inmagonzalezmolero@hotmail.com
European Journal of Clinical Nutrition
|December 24, 2010
Summary
Vitamin D deficiency affects one-third of the Spanish population. Higher 25-hydroxyvitamin D levels, especially above 35 ng/ml, are linked to lower parathyroid hormone (PTH) levels, indicating better bone health.
Area of Science:
- Endocrinology
- Nutritional Science
- Public Health
Background:
- Vitamin D deficiency is a widespread global health concern.
- Established reference values for vitamin D are lacking, particularly in Spain.
- Previous studies on vitamin D levels in Spain have not involved large, representative populations.
Purpose of the Study:
- To determine population-specific vitamin D concentrations in a representative Spanish sample.
- To investigate the relationship between 25-hydroxyvitamin D and intact parathyroid hormone (iPTH) levels.
- To identify factors influencing vitamin D status in the Spanish population.
Main Methods:
- Analysis of two Spanish cohorts (Asturias and Pizarra studies) with 2260 participants.
- Measurement of 25-hydroxyvitamin D, iPTH, calcium, phosphorus, and creatinine in 1262 subjects (aged 20-83).
- Prospective, population-based study design to ensure representativeness.
Main Results:
- Median 25-hydroxyvitamin D level was 22.46 ng/ml, and median iPTH was 42.29 pg/ml.
- 25-hydroxyvitamin D levels were higher in summer and correlated with age, creatinine, and iPTH.
- iPTH increased with age and rose significantly when 25-hydroxyvitamin D levels fell below approximately 30 ng/ml.
Conclusions:
- Approximately 33.9% of the Spanish population may be at risk of vitamin D deficiency.
- 25-hydroxyvitamin D levels exceeding 30 ng/ml can effectively rule out hyperparathyroidism.
- The age-related increase in iPTH is more pronounced in older individuals, even with similar vitamin D levels.
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