Tiredness in daily activities: a subjective measure for the identification of frailty among non-disabled community-living older adults.

The objective of this study was to determine whether the responses to questions about tiredness in daily activities is an early subjective sign of frailty indicating older community-living adults at increased risk for disability and mortality. Tiredness in daily activities as measured by the Mob-T Scale, maximal power in sustained work, and comorbid diseases were assessed together with sociodemographic variables in a sample of 705 non-disabled, 70-year old men and women surveyed in 1984. Vital status of members was determined prospectively over the next 15 years. Onset of disability was measured at 5-, 10-, and 15-year follow-up. Onset of disability among non-disabled 70-year old men and women was strongly related to tiredness in daily activities at 5- and 10-year follow-up. Scores on the Mob-T Scale were significantly associated with mortality during the aggregate 15-year follow-up period. Multiple stepwise regression analyses not only indicated that tiredness in daily activities is a strong independent predictor of both disability and mortality, but also that tiredness mediates the effects of comorbidity and maximal power in sustained work on disability/mortality. Self-reported tiredness in daily activities is suggested as a basis for identifying vulnerable frail subsets of older adults requiring targeted strategies for prevention.