Bidirectional relationship between subjective age and frailty: a prospective cohort study

Background Subjective age refers to how young or old individuals experience themselves to be and is associated with health status, behavioral, cognitive, and biological processes that influence frailty. However, little research has examined the relationship between subjective age and frailty among older adults. This study examined the bidirectional association between subjective age and frailty among community-dwelling older adults. Methods We used data from the 2011 to 2015 waves of the National Health and Aging Trends Study. Our sample consists of 2,592 community-dwelling older adults with complete data on main outcome variables. Subjective age was measured by asking participants, "What age do you feel most of the time?" Based on the five phenotypic criteria: exhaustion, unintentional weight loss, low physical activity, slow gait, and weak grip strength, frailty was categorized into robust = 0, pre-frailty = 1 or 2; frailty = 3 or more criteria met. Generalized estimating equation models were used to examine the concurrent and lagged association between subjective age and frailty. Results Participants were, on average, 75.2 +/- 6.8 years old, non-Hispanic whites (76 %), female (58 %). 77 % of the participants felt younger, 18 % felt the same, and 5 % felt older than their chronological age. About 45 %, 46 %, and 9 % of the participants were robust, pre-frailty and frailty in the first wave, respectively. Generalized estimating equations revealed that an "older" subjective age predicted a higher likelihood of pre-frailty and frailty (OR, 95 % CI = 1.93, 1.45-2.56). Conclusions These findings suggest that people with older subjective age are more likely to be pre-frail/frail. Subjective age could be used as a quick and economical screening for those who are potentially frailty or at risk for frailty.