Elderly can blame low sodium for fractures and falls

WASHINGTON - A new study has shown that older adults with even mildly decreased levels of sodium in the blood (hyponatremia) experience increased rates of fractures and falls.

Falls are a serious health problem for the elderly and account for about 50 percent of deaths due to injury in the elderly.

“Screening for a low sodium concentration in the blood, and treating it when present, may be a new strategy to prevent fractures,” comments Ewout J. Hoorn, (Erasmus Medical Center, Rotterdam, the Netherlands).

However, hyponatremia does not appear to affect the risk of osteoporosis, as defined by low bone mineral testing, so more research is needed to understand the link between sodium levels and fracture risk.

The study included more than 5,200 Dutch adults over age 55, all with initial information on sodium levels and six-year follow-up data on fractures and falls.

“A number of recent studies suggested a relationship between hyponatremia, falls, osteoporosis, and fractures,” Hoorn explains.

The authors’ goal was to confirm these possible associations using prospective, long-term follow-up data.

About eight percent of the study participants, all community dwelling adults, had hyponatremia. This group of older participants had a higher rate of diabetes and was more likely to use diuretics (water pills) than those with normal sodium levels. Subjects with hyponatremia had a higher rate of falls during follow-up: 24 versus 16 percent.

However, there was no difference in bone mineral density between groups, so hyponatremia was not related to underlying osteoporosis.

Nevertheless, the group with low sodium levels had a higher rate of fractures. With adjustment for other risk factors, the risk of vertebral / vertebral compression fractures was 61 percent higher in the older adults with hyponatremia. The risk of non-spinal fractures, such as hip fractures, was also significantly increased: a 39 percent difference.

The relationship between hyponatremia and fracture risk was independent of the increased rate of falls in the low-sodium group. Subjects with hyponatremia also had a 21 percent increase in the risk of death during follow-up.

The study has been presented at the American Society of Nephrology’s 43rd Annual Meeting and Scientific Exposition. (ANI)