Editorial: Water, Water Everywhere and Not a Drop to Drink

THERE is now good evidence that older persons fail to have an appropriate thirst response to dehydration (1)(2). Dehydration represents a common problem in older persons in hospitals (3) and in nursing homes (4)(5)(6). This is often associated with the onset of febrile illnesses or diarrhea. Although dehydration can develop with extraordinary rapidity in nursing home residents, it is considered a critical indicator for poor care in nursing homes. Dehydration is associated with a variety of complications including death, delirium, renal failure, orthostatic hypotension, pressure ulcers, falls, reduced salivary flow and periodontal sepsis, constipation, urge incontinence, and hyperosmolar diabetic coma (7)(8)(9)(10). These concerns were incorporated in the Modified Food Guide Pyramid for people over 70 years of age with the suggestion that daily fluid or water intake should be at least 8 glasses per day (11). Surprisingly there is little data concerning the normal fluid intake of community-dwelling older adults and whether this is associated with a higher prevalence of dehydration. In this issue of the Journal, Lindeman and colleagues (12) report that they could find no evidence of dehydration in community-dwelling elders ingesting 6 glasses of fluid per day. In a study of older inner-city African Americans, the prevalence of an elevated blood urea nitrogen/creatinine level (≥18) was 10% (13). Elevated levels of this measure of dehydration were associated with functional and cognitive decline and an increase in falls. DeCastro (14) could find no differences in overall fluid intakes of subjects ranging from 20 to 80 years of age. Older persons ingested more coffee and less soda and alcohol than younger persons. Younger persons tended to increase their fluid ingestion later in the day while older persons obtained most of their fluid by coingestion of solids at mealtimes. Overall these studies suggest that the majority of healthy older persons ingest sufficient fluids to maintain an adequate hydration status.