title: Clinical assessment of dehydration in older people admitted to hospital: what are the strongest indicators?
abstract: Due to an absence of published primary data, this study explores dehydration prevalence and the change in physiological parameters frequently used to assess dehydration (fluid deficit) in older hospitalized people, as no standard measurement method exists. This observational longitudinal cohort study recruited 43 people aged 60 years or over, voluntarily admitted to a tertiary teaching hospital's Geriatric and Rehabilitation Unit (GARU). Over 40 clinical, hematological and urinary biochemical parameters employed by medical officers during dehydration assessment, identified through literature, interviews and focus group were investigated. Short-term weight changes, intra- and inter-rater repeatability of dehydration assessments were completed to assess validation and precision of the clinician's clinical dehydration assessment. Systolic blood pressure drop on standing, sternal skin turgor, tongue dryness and body mass index (BMI) were associated with hydration status; demonstrated clinically meaningful differences between groups. BMI negatively confounded the association between dehydration and systolic blood pressure drop on standing. Physical, rather than biochemical, parameters more often identified mild dehydration. The findings challenge common expectations of hematological and physiological measurement changes occurring in older people clinically assessed as dehydrated and emphasize the need to adjust for potential confounders during exploration of the associations of clinical parameters with dehydration status.
authors.affiliation: Nutrition and Dietetics, Princess Alexandra Hospital Health, Ipswich Rd, Woolloongabba, Qld 4103, Brisbane, Australia. angela_vivanti@health.qld.gov.au
authors.forename: Angela
authors.initials: A
authors.lastname: Vivanti
authors.forename: Keren
authors.initials: K
authors.lastname: Harvey
authors.forename: Susan
authors.initials: S
authors.lastname: Ash
authors.forename: Diana
authors.initials: D
authors.lastname: Battistutta
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry; D001774:Blood Chemical Analysis; D015331:Cohort Studies; D016001:Confidence Intervals; D003681:Dehydration / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D015577:Geriatric Assessment; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008487:Medical History Taking; D015999:Multivariate Analysis; D016017:Odds Ratio; D010808:Physical Examination; D011237:Predictive Value of Tests; D015995:Prevalence; D011379:Prognosis; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D017678:Sex Distribution; D016482:Urinalysis