Stroke patients show dearth of vitamin D.

Having a stroke puts elderly people at an increased risk of breaking a hip. Scientists have assumed that a major reason is that an impaired sense of balance from a stroke leads to more falls. They've also observed a loss of bone density in the first few months after a stroke, possibly from reduced mobility during this phase of recovery.

Researchers now report that people recovering from a stroke have less vitamin D in their systems than do healthy peers. This finding could explain why stroke patients lose bone density, says Elizabeth A. Warburton, a neurologist at Cambridge University and Addenbrooke's Hospital in Cambridge, England. Vitamin D and calcium are necessary for bone maintenance (SN: 10/16/04, p. 248).

Warburton and her colleagues identified 34 stroke patients, average age 72, and 96 healthy people who matched the patients in age, gender, and other characteristics. The scientists took a blood sample from each patient shortly after his or her stroke and from the other volunteers at the same time. The team then obtained samples bimonthly from both groups for 14 months. The samples revealed that the stroke patients had only two-thirds as much vitamin D on average as did their healthy peers. In the first month after their strokes, most of the patients had vitamin D concentrations so low as to be "off the scale," Warburton says.

The take-home message for doctors, Warburton says, is that they should consider testing stroke patients for vitamin D deficiency and giving calcium and vitamin D supplements to those patients with low readings.