Background Frailty is a way to appreciate the variable vulnerability to declining health status of people as they age. No consensus for measuring frailty has been established. This study aimed to adapt a Frailty Index (FI) to the Canadian Longitudinal Study on Aging (CLSA) and evaluate its applicability in both younger and older adults.
Methods An FI was created based on 90 potential health deficits collected from adults aged 45–85 years at recruitment (N=21 241, 49.0% male). The construct validity of this instrument and the factor structure of the health deficits were evaluated.
Results The direction of associations between the FI and other variables were consistent with a priori hypotheses for construct validity. FI values were significantly associated with age (r=0.17; p<0.001), falls (r=0.12; p<0.001), injuries (r=0.12; p<0.001), formal home care (r =0.30; p<0.001), informal home care (r=0.32; p<0.001) and use of assistive devices (r=0.40; p<0.001). Values were negatively associated with male sex (r=−0.12; p<0.001), income (r=−0.34; p<0.001) and education (r=−0.17; p<0.001). Key factors among the health indicators were physical functioning, satisfaction with life and depressive symptoms. Results did not change when the sample was stratified by age and sex.
Conclusion The FI is a feasible method to evaluate frailty and capture frailty-related heterogeneity in populations aged 45–85 years. In this study, the FI had good construct validity in middle-aged and older adults, showing expected correlations with sociodemographic factors consistently across age groups. This method can be easily reproduced in similar datasets, making the FI a generalisable instrument.
- Measurement tool development
- Epidemiology of ageing
Statistics from Altmetric.com
Contributors This research was conducted by DMK under the supervision of LEG. DBH, CP, PR, and JR contributed to the conception of the study and acted as scientific advisors, providing feedback on the design and clinical relevance of the study. All authors contributed to the analysis and interpretation of data and preparation of the manuscript.
Funding Funding for the CLSA is provided by the Government of Canada through the Canadian Institutes of Health Research (CIHR) under grant reference: LSA 94473 and the Canada Foundation for Innovation.
Competing interests None declared.
Ethics approval Hamilton Integrated Research Ethics Board.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement This study employed data from the CLSA. The CLSA has recruited a nationally representative sample of participants aged 45–85 years from all 10 provinces of Canada. The CLSA is one of the largest and most comprehensive research platforms in the world. It was designed to examine ageing through a number of different lenses by collecting a wide range of information over time about the changing biological, medical, psychological, social, lifestyle and economic characteristics of participants. Researchers can learn more about the CLSA and submit a data access request through clsa-elcv.ca.