Does Allostatic Load in 50-89-Year-Olds Predict the Development of Frailty? Evidence From a National Longitudinal Study Over 12 Years

Frailty is characterised by a loss of function across several domains but is not an inevitable aspect of ageing and can be reversed with intervention. Determining those who are more likely to become frail before physical deficits become manifest will allow earlier intervention. One promising indicator of the potential for frailty is allostatic load, a physiological status associated with prolonged stress that is characterised by multisystem dysfunction. Previous research has sought to understand the links between allostatic load and frailty, but has not yet explored whether allostatic load may be a predictive factor at younger ages. The present study examined whether allostatic load can be used as a predictive indicator of frailty. Using data from four waves of the English Longitudinal Survey on Ageing (ELSA) collected over 12 years with a sample of 3248 people between 50 and 89 years old at baseline, discrete time event history analysis was used to determine if allostatic load is associated with the onset of pre-frailty and frailty. The findings indicate that allostatic load was a significant contributor to the occurrence of (pre-)frailty. Age and sex did not interact with allostatic load and frailty predictions, whilst in particular social support was identified as a possible modifiable factor. Allostatic load determination should be considered as a possible screening tool for future frailty risk in currently non-frail individuals.