Risk of hip fracture higher in vitamin D-deficient women: study

Women with low levels of vitamin D have an increasedrisk of hip fracture, a new study suggests.

The findings were presented Thursday at the 29th annual meeting of the American Society for Bone and Mineral Research in Honolulu.

"The risk of hip fractures was 77 per cent higher among women whose 25 hydroxyvitamin D levels were at the lowest concentrations," said Dr. Jane Cauley, a professor of epidemiology, the University of Pittsburgh Graduate School of Public Health.

"This effect persisted even when we adjusted for other risk factors such as body mass index, family history of hip fracture, smoking, alcohol use and calcium and vitamin D intake."

Researchers studied the patient data of 400 women who had suffered a hip fracture over a median of 7.1 years. They measured the women's blood levels of hydroxyvitamin D, an indicator of vitamin D status, and compared those levels with women in a control group.

The women in both study groups were matched for age, race, ethnicity and the date of relevant blood work.

Scientists found that as the vitamin D levels dropped, the risk of hip fractures rose. Vitamin D is produced in the skin after exposure to the sun.

In June, Health Canada advised all adults living in Canada to consider taking 1,000 international units (IU) of vitamin D supplements a day in the fall and winter, when sun exposure in the country is not high enough to produce adequate vitamin D naturally.

It also recommended that adults at higher risk of having vitamin D deficiency consider taking the 1,000 IU supplement year round.