Bone mineral density in acute stroke patients: low bone mineral density may predict first stroke in women.

BACKGROUND AND PURPOSE Osteoporosis and stroke share several risk factors, including age, smoking, low physical activity, and hypertension. Thus, low bone mineral density (BMD) and high stroke risk may be related. We examined the relationship between BMD and acute stroke in noninstitutionalized men and women aged >/=60 years. METHODS Sixty-three stroke patients (33 women and 30 men) and 188 control subjects from the general population were included. BMD was measured by using dual-energy x-ray absorptiometry at both proximal femurs. The measurements of the stroke patients were performed 6 days after the onset of stroke. RESULTS The BMD at the femoral neck in the female stroke patients was 8% lower than in the control subjects (P:=0.007). In men, no difference in BMD between the stroke patients and their controls was found. Women with BMD values in the lowest quartile had a higher risk of stroke than women with BMD values in the highest quartile (OR 4.8), and the probability value for linear trend over the quartiles was statistically significant (P:=0.003). The OR for stroke increased 1.9 per SD (0.13 g/cm(2)) reduction in BMD, and the association between low BMD and stroke in women remained significant when the analysis was adjusted for potential confounders. CONCLUSIONS Female, but not male, stroke patients have lower BMD than population controls. Low BMD may predict stroke in women.