The relation of hydration status to declarative memory and working memory in older adults

J Nutr Health Aging. 2010 Dec;14(10):840-3. doi: 10.1007/s12603-010-0108-8.


Objectives: Prior studies have suggested a relationship between dehydration and poor cognitive performance. The present study examined the relationships among hydration status, declarative memory and working memory skills, and blood pressure in a sample of older community dwelling females.

Design: Data was analyzed from a larger study; relationships among hydration status, blood pressure, and cognitive measures were assessed with correlation and meditational analyses.

Setting: Laboratory.

Participants: 21 postmenopausal women (mean age 60.3, SD 8.03).

Measures: Hydration status was measured using bioelectrical impedance, baseline blood pressure was assessed using a Colin Pressmate, and cognition was examined using the Auditory Verbal Learning Test and Auditory Consonant Trigrams.

Results: Bioelectrical impedance total body water by weight was found to be related to working memory, r = .47, p = .04, and memory skills, r = .54, p = .01. Total body water by weight was also found to be related to diastolic blood pressure, r = -.56, p = .01, which in turn was related to working memory, r = -.67, p = .002, and declarative memory, r = -.57, p = .009, skills. When diastolic blood pressure was accounted for, the relationship between hydration status and cognitive skills was attenuated. A similar pattern of results was seen for systolic blood pressure, although findings did not reach statistical significance.

Conclusions: Results emphasize the importance of considering hydration status and blood pressure when interpreting cognitive performance in older adults.

MeSH terms

  • Aged
  • Aging*
  • Algorithms
  • Blood Pressure
  • Body Weight
  • Dehydration / physiopathology*
  • Electric Impedance
  • Female
  • Humans
  • Hypertension / physiopathology
  • Memory / physiology*
  • Memory Disorders / epidemiology*
  • Memory, Short-Term / physiology
  • Middle Aged
  • Neuropsychological Tests
  • Nutritional Status*
  • Postmenopause
  • Severity of Illness Index
  • United States / epidemiology