To achieve bone health in general population, the Institute of Medicine (IOM) guidelines and the Endocrine Society guidelines recommend 50 and 75 nmol/L respectively as sufficient levels of serum 25-hydroxyvitamin D (25(OH)D). Researchers from China wanted to understand if there were positive effects with high levels of vitamin D on bone mineral density (BMD).
Using data from the National Health and Nutrition Examination Survey (NHANES), the team used a cross-sectional study design to analyze the relationship between serum 25(OH)D levels and osteoporosis in 2,058 postmenopausal women (age 50+).
Multiple logistic regression was used to explore the relationship between serum 25(OH)D and osteoporosis of total femur, femoral neck and lumbar spine, with stratified analyses for age (<65 and ≥65 years), BMI (<25, 25 to <30, ≥30 kg/m2) and survey months (winter months and summer months).
In the fully adjusted model, compared with serum 25(OH)D levels <50 nmol/L, the odds ratios (ORs) and 95% confidence intervals (CIs) of serum 25(OH)D 50–<75 nmol/L and ≥75 nmol/L were 0.274 (0.138, 0.544) and 0.374 (0.202, 0.693) in osteoporosis of total femur, 0.537 (0.328, 0.879) and 0.583 (0.331, 1.026) in osteoporosis of femoral neck, and 0.614 (0.357, 1.055) and 0.627 (0.368, 1.067) in osteoporosis of lumbar spine, respectively.
The results of this study showed that postmenopausal women with higher serum 25(OH)D levels are less likely to suffer from osteoporosis. Both serum 25(OH)D levels of 50–<75 nmol/L and ≥75 nmol/L were protective against osteoporosis, compared with serum 25(OH)D levels <50 nmol/L. Specifically, high serum 25(OH)D levels had a significant protective effect on total femur and femoral neck, but not on lumbar spine. After age stratification, the protective effect of high 25(OH)D levels was observed at all 3 skeletal sites in elderly women aged ≥65 years.
The authors concluded that adequate vitamin D may reduce the risk of osteoporosis in postmenopausal women in the United States, especially in those aged 65 years and older. More attention should be given to serum 25(OH) D levels to prevent osteoporosis.
Source: Wang D, Yang Y. The Relationship Between Serum 25-Hydroxyvitamin D Levels and Osteoporosis in Postmenopausal Women. Clinical Interventions in Aging. 2023;18:619-627.
