Point-of-Care Saliva Osmolarity Testing for the Screening of Hydration in Older Adults With Hypertension

Neng Mira Atjo; Gita Vita Soraya; Rosdiana Natzir; Hasyim Kasyim; Haerani Rasyid; Gursharan Chana; Michael Erlichster; Efstratios Skafidas; Marhaen Hardjo

doi:10.1016/j.jamda.2022.08.015

Point-of-Care Saliva Osmolarity Testing for the Screening of Hydration in Older Adults With Hypertension

J Am Med Dir Assoc. 2022 Dec;23(12):1984.e9-1984.e14. doi: 10.1016/j.jamda.2022.08.015. Epub 2022 Sep 27.

Authors

Neng Mira Atjo¹, Gita Vita Soraya², Rosdiana Natzir³, Hasyim Kasyim⁴, Haerani Rasyid⁵, Gursharan Chana⁶, Michael Erlichster⁷, Efstratios Skafidas⁸, Marhaen Hardjo⁹

Affiliations

¹ Department of Biomedicine, Graduate School Hasanuddin University, Makassar, Indonesia; Department of Nursing, Faculty of Health Sciences, University of West Sulawesi, Majene, Indonesia.
² Department of Biomedicine, Graduate School Hasanuddin University, Makassar, Indonesia; Department of Biochemistry, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia; Department of Neurology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia. Electronic address: gitavitasoraya@unhas.ac.id.
³ Department of Biomedicine, Graduate School Hasanuddin University, Makassar, Indonesia; Department of Biochemistry, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia.
⁴ Division of Renal Diseases and Hypertension, Department of Internal Medicine, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia.
⁵ Division of Renal Diseases and Hypertension, Department of Internal Medicine, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia; Department of Clinical Nutrition, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia.
⁶ MX3 Diagnostics Inc., VIC, Australia; Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, VIC, Australia.
⁷ MX3 Diagnostics Inc., VIC, Australia.
⁸ MX3 Diagnostics Inc., VIC, Australia; Department of Electrical and Electronic Engineering, Melbourne School of Engineering, The University of Melbourne, VIC, Australia.
⁹ Department of Biomedicine, Graduate School Hasanuddin University, Makassar, Indonesia.

PMID: 36174654
DOI: 10.1016/j.jamda.2022.08.015

Abstract

Objectives: Older adults have an elevated risk of dehydration, a state with proven detrimental cognitive and physical effects. Furthermore, the use of diuretics by hypertensive patients further compounds this risk. This prospective study investigated the diagnostic accuracy of point-of-care (POC) salivary osmolarity (SOSM) measurement for the detection of dehydration in hypertensive adults with and without diuretic pharmacotherapy.

Design: Prospective diagnostic accuracy study.

Setting: Home visits to patients recruited from 4 community health centers in West Sulawesi, Indonesia.

Participants: A total of 148 hypertensive older adults (57 men, 91 women). The mean ages of male and female patients were 69.4 ± 11.4 and 68.1 ± 7.8 years, respectively.

Methods: Hypertensive adults were divided into 2 groups based on the presence of diuretics in their pharmacotherapeutic regimen. First-morning mid-stream urine samples were used to perform urine specific gravity (USG) testing. Same-day SOSM measurements were obtained using a POC saliva testing system.

Results: Both USG (P = .0002) and SOSM (P < .0001) were significantly elevated in hypertensive patients with diuretic pharmacotherapy. At a USG threshold of ≥1.030, 86% of diuretic users were classified as dehydrated compared with 55% of non-using participants. A strong correlation was observed between USG and SOSM measurements (r = 0.78, P < .0001). Using a USG threshold of ≥1.030 as a hydration classifier, an SOSM threshold of ≥93 mOsm had a sensitivity of 78.6% and a specificity of 91.1% for detecting dehydration.

Conclusions and implications: Hypertensive patients on diuretics have significantly higher first-morning USG and SOSM values, indicating a higher likelihood of dehydration relative to those on other classes of antihypertensive medication. POC SOSM assessment correlates strongly with first-morning USG assessment, and represents a rapid and noninvasive alternative to urinary hydration assessment that may be applicable for routine use in populations with elevated risk of dehydration.

Keywords: Point-of-care; diuretic; elderly; saliva osmolarity.

MeSH terms

Aged
Aged, 80 and over
Female
Humans
Hypertension* / diagnosis
Hypertension* / drug therapy
Male
Middle Aged
Point-of-Care Systems*
Prospective Studies