The association of self- and interviewer-reported cognitive problems with frailty progression and subsequent all-cause mortality risk: a large-scale cohort study.

BACKGROUND

This study aims to investigate the association between self-reported cognitive problems (SCP), interviewer-reported cognitive problems (ICP), and their combined effect on frailty and subsequent all-cause mortality risk.

METHODS

A total of 6,793 Chinese adults from the China Health and Retirement Longitudinal Study (CHARLS) were included. Self-reported memory (5-point scale) and interviewer-reported frequencies of asking for clarification (6-point scale) were used to define SCP and ICP (dichotomized). Cox regression models were applied to estimate the relative risks of frailty and subsequent mortality. Additionally, group-based trajectory modeling (GBTM) was used to explore the association between individual and combined SCP and ICP with frailty index trajectory groups.

RESULTS

In our study, SCP was associated with frailty progression (HR = 1.83, 95% CI: 1.46-2.29) and increased risk of all-cause mortality (HR = 1.35, 95% CI: 1.02-1.79). The combination of SCP and ICP was associated with both frailty progression (HR = 2.32, 95% CI: 1.74-3.10) and increased risk of all-cause mortality (HR = 1.66, 95% CI: 1.15-2.40). For transitions in SCP/ICP status, the shift from Non-SCP to SCP and from Non-SCP & Non-ICP to SCP & ICP both led to an increased risk of frailty progression. Furthermore, the SCP & ICP group exhibited the positive associations with both the persistently moderate frailty trajectory (OR = 1.95, 95% CI: 1.72-2.22) and the persistently high frailty trajectory (OR = 5.38, 95% CI: 4.63-6.25). The mediation analysis revealed that the frailty score mediated the link between the combined status of SCP and ICP with all-cause mortality, accounting for 20.70% of the association (P for proportion < 0.001).

CONCLUSIONS

The study suggested that the combination of self-reported and interviewer-reported cognitive problems was most strongly associated with frailty progression and subsequent all-cause mortality.