Prevalence and Risk Score for Hypertonic Dehydration Among Community-Dwelling Older Adults: an Analysis of the Bangkok Falls Study

Introduction: Dehydration is associated with morbidity, and many factors affect dehydration in older adults including age and medication use. This study determined the prevalence of hypertonic dehydration (HD) and factors affecting HD in older adults and developed a risk score (a set of consistent weights that assign a numerical value to each risk factor) which are potentially useful in predicting HD among community-dwelling Thai older adults.Methods: Data were obtained from a cohort study of community-dwelling older adults aged >= 60 years in Bangkok, Thailand between October 1, 2019, and September 30, 2021. Current HD was defined as a serum osmolality >300 mOsm/kg. Univariate and multivariate logistic regression analyses were used to identify factors associated with current and impending HD. The risk score for current HD was developed based on the final multiple logistic regression model.Results: A total of 704 participants were included in the final analysis. In this study, 59 (8.4%) participants had current HD and 152 (21.6%) had impending HD. We identified three risk factors for HD in older adults; age >= 75 years (adjusted odds ratio (aORs) 2.0, 95% confidence interval [CI]: 1.16-3.46), underlying diabetes mellitus (aORs 3.07, 95%CI: 1.77-5.31) and use of ss-blocker medication (aORs 1.98, 95%CI: 1.04-3.78). The increasing risks of current HD with increasing risk scores were 7.4% for a score of 1, 13.8 % for a score of 2, 19.8% for a score of 3, and 32.8% for a score of 4. Conclusion: One-third of the older adults in this study had current or impending HD. We identified risk factors for HD and created a risk score for HD in one group of community-dwelling older adults. Older adults with risk scores of 1-4 were at 7.4%-32.8% risk for current HD. The clinical utility of this risk score requires further study and external validation.