Abdominal obesity and hydration status as protective factors against mortality in older adults: A prospective study.

Objectives: The aim of this study was to assess the association between different anthropometric and body composition techniques for defining obesity status and to investigate their clinical implications in older hospitalized patients, both during their hospitalization and after discharge.

Methods: This prospective study included patients ≥60 y of age. They were followed for 18 mo to assess mortality and hospital length of stay. Anthropometric measurements and body composition were evaluated, including body mass index (BMI), waist circumference, waist-to-height ratio, body fat percentage, total body water percentage, and muscle mass. These measurements are associated with prognosis and survival.

Results: A higher BMI, excessive body fat, higher total body water percentage, and abdominal obesity were associated with a lower risk for death (P < 0.05). Higher hydration levels were identified as an independent protective factor against mortality. Obesity, defined by body fat percentage, was associated with a shorter hospital stay (P < 0.05).

Conclusion: The present study adds to the growing body of evidence supporting the existence of the obesity paradox in hospitalized older patients. Additionally, our novel finding reveals that higher levels of total body water percentage are associated with decreased odds of mortality. The study emphasizes the importance of considering other anthropometric measurements and body composition in addition to BMI, considering its limitations. These findings have important implications for health care providers when recommending changes in nutritional status for the older adult population.