Hyponatremia: Special Considerations in Older Patients

Abstract

Hyponatremia is especially common in older people. Recent evidence highlights that even mild, chronic hyponatremia can lead to cognitive impairment, falls and fractures, the latter being in part due to bone demineralization and reduced bone quality. Hyponatremia is therefore of special significance in frail older people. Management of hyponatremia in elderly individuals is particularly challenging. The underlying cause is often multi-factorial, a clear history may be difficult to obtain and clinical examination is unreliable. Established treatment modalities are often ineffective and carry considerable risks, especially if the diagnosis of underlying causes is incorrect. Nevertheless, there is some evidence that correction of hyponatremia can improve cognitive performance and postural balance, potentially minimizing the risk of falls and fractures. Oral vasopressin receptor antagonists (vaptans) are a promising innovation, but evidence of their safety and effect on important clinical outcomes in frail elderly individuals is limited.

Patterns of Drug Use and Serum Sodium Concentrations in Older Hospitalized Patients: A Latent Class Analysis Approach

“…A number of reviews have elegantly discussed the available evidence of the causative role of several drugs on the risk of hyponatremia, particularly in older patients [3, 7, 12]. However, a substantial number of studies (1) comprised small population groups and case reports, (2) included patients only receiving the investigated drug, and (3) did not ascertain the potential contributing role of other clinical and demographic characteristics on the incidence of hyponatremia [3, 7, 12].…”

“…However, a substantial number of studies (1) comprised small population groups and case reports, (2) included patients only receiving the investigated drug, and (3) did not ascertain the potential contributing role of other clinical and demographic characteristics on the incidence of hyponatremia [3, 7, 12]. These issues are particularly relevant in older patients with multiple disease states and polypharmacy.…”

“…The high prevalence of this electrolyte abnormality in older hospitalized patients might be secondary to the presence of one, or more, disease states characterized by alterations in sodium and water balance, impaired homeostasis, and polypharmacy, as well as in-hospital iatrogenic interventions [3]. There is increasing evidence that lower NaC values are independently associated with adverse clinical outcomes in old age [3]. More specifically, they predict loss of independence, increased length of stay, and mortality in older hospitalized patients [4–6].…”

“…The increased risk of hyponatremia, an independent predictor of adverse outcomes in the older population, with several commonly prescribed drugs warrants regular medication reviews to prevent and rectify this electrolyte abnormality, potentially improving outcomes in this group [3]. However, investigating associations between drugs and NaC in patients with concomitant prescribed medications and multiple disease states presents significant challenges.…”

Diagnosis and management of hyponatraemia in the older patient

“…Over 40% of elderly patients admitted to intensive care experience hyponatraemia at some time during their hospitalisation, and chronic hyponatraemia has been observed in 18% of aged care facility residents . The causes of hyponatraemia are multiple and varied . Age‐related comorbidities, polypharmacy and age‐related physiological changes add complexity often resulting in suboptimal management in older patients.…”