Vitamin D-deficiency and post-fracture changes in lower extremity function and falls in women with hip fractures.
We determined the prevalence of vitamin D deficiency and lower extremity function in women with hip fractures. Women with extremely low vitamin D levels had reduced lower extremity muscle function and increased falls 1 year later. Ensuring vitamin D sufficiency after a hip fracture may improve function and reduce falls.


BACKGROUND
Hip fractures are the most devastating of fractures, commonly leading to loss of independent ambulation and living. In this retrospective analysis we determined the prevalence of vitamin D deficiency in women with hip fractures and the association between 25-hydroxyvitamin D [25(OH)D] levels and functional impairment one year later.


METHODS
One hundred ten community-dwelling women with hip fractures were recruited from Boston, MA (n = 30) and Baltimore, MD (n = 80) before 1998 and 25(OH)D levels were measured by radioimmunoassay. In a subset of women from Baltimore, a performance measure of the lower extremities using the lower extremity gain scale (LEGS) was measured at 2, 6, and 12 months. Falls, grip strength, chair rise time, walking speed, and balance were also determined.


RESULTS
Vitamin D insufficiency defined as a 25(OH)D <or=32 ng/mL was present in 96% of the women with hip fractures and 38% had extremely low levels <or=9 ng/mL. At 1 year post-fracture, compared to women with a 25(OH)D >9 ng/mL, those with 25(OH)D <or=9 ng/mL had poorer LEGS performance (p < 0.0001) and higher fall rates, without group differences in grip strength or balance.


CONCLUSIONS
Vitamin D sufficiency may have important effects on lower extremity function following hip fractures, without excessive healthcare costs.
LeBoff
M S
MS
Skeletal Health and Osteoporosis Center and Bone Density Unit, Endocrine, Diabetes, and Hypertension Division, Brigham and Women's Hospital, 221 Longwood Ave, Boston, MA 02115, USA. mleboff@partners.org
Hawkes
W G
WG
Glowacki
J
J
Yu-Yahiro
J
J
Hurwitz
S
S
Magaziner
J
J
D000058:Accidental Falls; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D018737:Hand Strength; D006620:Hip Fractures / Q000150:complications* / Q000503:physiopathology / Q000534:rehabilitation; D006801:Humans; D035002:Lower Extremity / Q000503:physiopathology*; D008875:Middle Aged; D020127:Recovery of Function; D012189:Retrospective Studies; D014808:Vitamin D Deficiency / Q000150:complications* / Q000503:physiopathology