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

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. (c) 2022 AMDA - The Society for Post-Acute and Long-Term Care Medicine.

Automated summary

This study investigated the diagnostic accuracy of salivary osmolarity measurement for detecting dehydration in hypertensive adults with and without diuretic pharmacotherapy. The results showed that hypertensive patients on diuretics had higher urine specific gravity and salivary osmolarity values, indicating a higher risk of dehydration. Salivary osmolarity assessment correlated strongly with urine specific gravity assessment.