Vitamin D Deficiency and Risk of Hip Fractures Among Disabled Elderly Stroke Patients

Abstract

Background and Purpose-Risk of hip fracture after stroke is 2 to 4 times that in a reference population. Osteomalacia is present in some patients with hip fractures in the absence of stroke, while disabled elderly stroke patients occasionally have severe deficiency in serum concentrations of 25-hydroxyvitamin D (25-OHD) (Յ5 ng/mL). To determine the effects of vitamin D status on hip fracture risk, we prospectively studied a cohort of patients with hemiplegia after stroke who were aged at least 65 years. Methods-We compared baseline serum indices of bone metabolism, bone mineral density, and hip fracture occurrence in stroke patients with serum 25-OHD Յ25 nmol/L (Յ10 ng/mL; deficient group, nϭ88) with findings in patients from the same cohort who had 25-OHD levels 26 to 50 nmol/L (10 to 20 ng/mL; insufficient group, nϭ76) or Ն51 nmol/L (Ն21 ng/mL; sufficient group, nϭ72). Results-Over a 2-year follow-up interval, hip fractures on the paretic side occurred in 7 patients in the deficient group and 1 patient in the insufficient group (PϽ0.05; hazard ratioϭ6.5), while no hip fractures occurred in the sufficient group. The 7 hip fracture patients in the deficient group had an osteomalacic 25-OHD level of Ͻ5 ng/mL. Higher age and severe immobilization were noted in the deficient group. Serum 25-OHD levels correlated positively with age, Barthel Index, and serum parathyroid hormone. Conclusions-Elderly disabled stroke patients with serum 25-OHD concentrations Յ12 nmol/L (Յ5 ng/mL) have an increased risk of hip fracture. Immobilization and advanced age cause severe 25-OHD deficiency and consequent reduction of BMD.

Effect of Folate and Mecobalamin on Hip Fractures in Patients With Stroke

“…The high incidence of hip fractures in elderly patients with stroke may be attributed to frequent falls, 7,30 as well as osteoporosis due to disuse as suggested by our findings and a study on vitamin D deficiency. 7 In our study, the number of falls was similar in both groups during the follow-up period and the combined therapy with folate and mecobalamin prevented hip fractures in patients with stroke despite frequent falls.…”

“…7,31 The incidence in our placebo group (8.6% in 2 years) was substantially higher, which may have been related to a low intake of vitamin D and calcium in a traditional Japanese diet, particularly common among the elderly Japanese population. Reduced sunlight exposure with decreased active 1,25-dihydroxyvitamin D may also have contributed to the high prevalence of fractures in the present series.…”

“…[2][3][4][5] Hip fractures are associated with more deaths, disabilities, and medical costs than all other osteoporosis-related fractures combined. 6 We previously measured the bone mineral density (BMD) in patients with stroke in the second metacarpal bone and demonstrated a decrease in the bone mass in the hemiplegic limb that corresponded to the degree of palsy and vitamin D deficiency, 7 which may explain why hip fractures in patients poststroke occur almost exclusively on the hemiplegic side of the body.…”

“…Reduced sunlight exposure with decreased active 1,25-dihydroxyvitamin D may also have contributed to the high prevalence of fractures in the present series. 7,31 Furthermore, decreased BMD on the hemiplegic side depends on the degree of motor palsy, 39 and the severity of the neurological condition may have affected the prevalence of fractures through an effect on osteoporosis.…”

Low-Dose Vitamin D Prevents Muscular Atrophy and Reduces Falls and Hip Fractures in Women after Stroke: A Randomized Controlled Trial

“…Falls may result in hip fractures almost on the paretic side [2], and elucidation of predisposing factors related to falls are important, especially if these factors are modifiable and falls can be prevented. Approximately 40% of patients fall within the first year of a stroke [3] and the incidence of hip fracture is up to 4 times higher in stroke patients as compared to controls [4].…”