Transitions in frailty states and associated factors: a multistate analysis of the Italian Longitudinal Study on...

Frailty is recognized as a dynamic and potentially reversible process, but comprehensive studies on its progression/regression are rare.

To investigate the frequency and characteristics of frailty transitions over time in a representative sample of older Italians.

As secondary analysis of the Italian Longitudinal Study on Aging (ILSA) population-based cohort, we studied all participants (n = 1339; women 47.5 %, age 72.7 ± 5.1) with complete information on changes in frailty status (or death) between consecutive ILSA surveys (T0, T1, T2).

Frailty was operationalized according to Fried phenotype, analysing transitions between frailty, or death, during T0-T1, T1-T2 (4-, 5-year length). Transition probability at 1, 3, 5 years was estimated through non-hidden continuous-time Markov models, with death as absorbing state. Factors influencing transitions were evaluated with Cox proportional Hazard Ratios (HR).

We observed 1931 transitions between frailty states and 241 to death. The estimated probability of: maintaining a stable frailty status (∼80 % within 1 year) halved at 5 years; worsening increased steeply over time and was always greater among women; improvement/remission was twice higher at medium (about 20 % among Frail->preFrail women, preFrail->nonFrail men) than short term. Depressive symptoms were the strongest predictor of worsening [nonFrail->Frail: women HR 3.63 (95 %CI 1.45-9.10), men HR 3.78 (95 %CI 2.0-7.13)]. Not having a spouse/partner was associated with a 30 % reduced probability of pre-frailty remission in both sexes.

Our findings confirm the fluctuating nature of frailty with an ample chance of remission/improvement, highlighting the importance of a prompt, multidimensional preventive approach, including psycho-social dimensions.