Hyponatraemia in very old nonhospitalised people: association with drug use.

Objective: Hyponatraemia is one of the major problems in geriatric inpatients. However, in nonhospitalised elderly, the preponderance of hyponatraemia and the importance of the effect of drug intake on serum sodium concentrations are little known. This study investigated the prevalence of hyponatraemia in very old nonhospitalised people, controlling for factors that may induce hyponatraemia (especially drug use).