NASHVILLE, Tenn.Hyponatremia may place elderly patients at increased risk for bone fractures, according to researchers.
Harminder S. Sandhu, MD, and colleagues at Lenox Hill Hospital in New York, evaluated sodium levels in 364 cases of bone fracture (hip, femur, pelvis) in patients aged 65 years and older who presented in the hospital's emergency department and 364 age-matched nonfracture patients.
The incidence of hyponatremia was 9.1% in fracture patients compared with 4.1% in nonfracture patients. Hyponatremia was mild (130-134 mEq/L) to moderate (129 mEq/L or less).
In the fracture group, 75.3% of subjects were women, and women were 1.6 times more likely than men to have sustained a fracture, Dr. Sandhu's group reported. Among fracture patients with hyponatremia 18.2% were taking selective serotonin reuptake inhibitors, whereas no patients in the nonfracture group were taking these drugs. In the nonfracture group, hyponatremia was more commonly associated with pulmonary problems and diuretic use, according to the researchers.
In a poster presented here at the National Kidney Foundation 2009 Spring Clinical Meetings, the investigators noted that previous studies have shown that elderly patients with hyponatremia are at elevated risk for disturbances, altered cognition, and falls, and falls may be associated with fractures.
“Because hyponatremia is associated with changes in mentation and motor skills, these findings suggest that careful monitoring of serum sodium levels is important in all elderly patients, especially those who take antidepressants,” they wrote.