Endocrine Abstracts

JOINT1063

Background: Plasma sodium disorders (dysnatremia) are the most common electrolyte disorders in hospitalized patients. However, data on their prevalence and incidence in community-dwelling and generally healthy older adults are currently scarce. The aim of this study was to estimate the prevalence and incidence of dysnatremia among community-dwelling older adults from five European countries.

Material and Methods: We performed a secondary analysis of DO-HEALTH, a multicenter clinical trial including community-dwelling participants aged ≥70 years from Austria, France, Germany, Portugal, and Switzerland, without major health events in the five years prior to inclusion. The trial duration was three years with yearly in-person clinical visits and blood samples. Data about sodium were collected yearly. Dysnatremia was defined as sodium levels <135 mmol/l (hyponatremia) or >145 mmol/l (hypernatremia). Incidence rates (IR) and 95% confidence intervals over the study period were estimated using negative binomial regression models.

Results: Out of the 2157 DO-HEALTH participants, 2141 (99.3%) had available sodium at baseline. At baseline, the overall prevalence of any dysnatremia, hyponatremia and hypernatremia were 3.4%, 2.4%, and 1.0%, respectively. Participants with dysnatremia at baseline were more likely to be older, have a lower body mass index and use thiazide or thiazide-like drugs, compared to participants with normonatremia. Over the three years of follow-up, the overall IR of dysnatremia, hyponatremia and hypernatremia were 3.3 (2.7-3.9), 2.1 (1.6-2.7) and 1.2 (0.9-1.6) per 100 person-years, respectively. The use of five or more medications and the use of thiazide or thiazide-like drugs at baseline were significantly associated with higher incidence rates of any dysnatremia and higher incidence rates of hyponatremia over the follow-up. No difference in the incidence rates of any dysnatremia, hyponatremia and hypernatremia were observed by sex or age.

Conclusion: In a large sample of European generally healthy community-dwelling older adults, the prevalence of any dysnatremia was 3.4%. Over three years of follow-up, the overall incidence rate of any dysnatremia was 3.3 per 100 person-years, with higher rates among individuals using more than five medications and using thiazide or thiazide-like drugs. These findings suggest that careful monitoring of sodium levels may be relevant even in generally healthy older adults.