ESA-SRB-AOTA 2019

Hyponatraemia as a surrogate marker for frailty and geriatric syndrome: a study in an Australian regional hospital (#559)

Ru H New 1 , Daryl H Wong 2 , Jim H Wong 3 , Shirantha Adikari 3
  1. University of Sydney, Sydney, NSW, Australia
  2. Medicine, University of Queensland, Brisbane, QLD, Australia
  3. Cairns Hospital, Redlynch, QLD, Australia

Background: Hyponatremia is the most common electrolyte imbalance in Australian hospitals today1-3, particularly with respect to the geriatric population.1,2,4 Although mild hyponatremia is usually asymptomatic,1 studies have inferred that hyponatremia is associated with increased falls,1,5 frailty,6 delirium,2 dementia,3 and mortality.1,6 Currently, an objective measurable marker of frailty has not been found.  

Aim: To investigate the prevalence of hyponatremia in the geriatric population as well as its impact on frailty and geriatric syndrome.

Methods: Retrospective study of 235 patients aged 70 and above who were admitted in the Geriatric Unit in Cairns Hospital from 1st January 2018 to 30th June 2018. Comparison were made between patients with normal serum sodium, with those with mild, moderate and severe hyponatremia in several aspects of geriatric syndrome. Data collated was analysed using Microsoft Excel and presented in mean values, frequencies and percentages. Student t-test and N-1 Pearson’s Chi-squared test7.8 were used to determine statistical significance.

Results: Patients with hyponatremia were associated with higher CSHA (Canadian Study of Health and Aging) Clinical Frailty Scale scores9 (mean 3.79+/-1.79 in patients with normal sodium versus 4.29+/-1.75, p=0.04 in patients with hyponatraemia), history of falls (61.04% versus 74.68%, p=0.03), and prolonged hospital admission (average 21.48 days +/-18.51 versus 31.43 days +/-18.31, p<0.001). There also appeared to be a mild increase risk of delirium in patients with hyponatremia (31.17% versus 41.77%, p=0.12). 

Conclusion: Hyponatremia is associated with several aspects of geriatric syndrome. These findings support the use of hyponatremia as a potential surrogate marker of frailty and geriatric syndrome with further implications in prognostic capabilities.

 

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