Vitamin D supplementation is required to normalize serum level of 25OH-vitamin D in older adults: an observational study of 974 hip fracture inpatients.

Background: Vitamin D deficiency is highly prevalent in older adults in all continents. In this study we assessed the vitamin D status of hip fracture subjects across different hospitals in a real word situation using the data from a multicenter cohort study on outcomes in orthogeriatric units.

Methods: We performed a prospective cohort study on 974 consecutive patients 75 yr or older admitted with fragility hip fracture over a 12 months period at 4 general hospitals of different districts in Emilia Romagna Region, Italy. Data collected included comorbidity, cognitive impairment, prefracture functional status, walking ability, living arrangement along with the use of antiosteoporotic drugs, serum intact PTH and serum 25-hydroxyvitamin D [25(OH)D].

Results: Mean 25(OH)D serum levels were 12.2±9.4 ng/ml and 84.2% of patients had levels below recommended values. Male had a higher probability to have values within the reference range [odds ratio (OR): 1.74 (1.13-2.67); p=0.012] while living in nursing resulted negatively related even if only close to statistical significance [OR: 0.24 (0.06-1.02); p=0.051]. Vitamin D supplementation appeared to be the strongest factor associated with adequate level of vitamin D levels [OR: 4.50 (2.57-7.88); p<0.001).

Conclusion: This study confirmed the very high rate of severe vitamin D deficiency in Italian subjects admitted with hip fracture. Our study also showed that supplementation of vitamin D is the strongest determinant influencing serum 25(OH)D level of older persons with hip fracture and these results should be taken into account when planning treatment in older persons.