Dongyu Zhang, Erin M. Mobley, Todd M. Manini, Christiaan Leeuwenburgh, Stephen D. Anton, Caretia J. Washington, Daohong Zhou, Alexander S. Parker, Paul G. Okunieff, Jiang Bian, Yi Guo, Marco Pahor, Robert A. Hiatt, and Dejana Braithwaite
Epidemiologic evidence reporting the role of frailty in survival among older adults with a prior cancer diagnosis is limited.A total of 2050 older adults (≥60 years old) surviving for at least 1 year after a cancer diagnosis and 9474 older adults without a cancer history from the National Health and Nutrition Examination Survey (1999-2014) were included for analysis. The exposure variable, a 45-item frailty index (FI), was categorized on the basis of validated cutoffs (FI ≤ 0.10 [fit], 0.10FI ≤ 0.21 [prefrail], and FI0.21 [frail]). All-cause mortality was ascertained via the National Death Index. Multivariable Cox proportional hazards models were used to estimate adjusted hazard ratios (aHRs) and 95% confidence interval (CIs) for the FI, and this was followed by restricted cubic splines depicting dose-response curves.For older cancer survivors, the mean age at the baseline was 72.6 years (SD, 7.1 years); 5.9% were fit, 38.2% were prefrail, and 55.9% were frail. Older adults without a cancer history were slightly younger (mean age, 70.0 years) and less frail (47.9% were frail). At each level of the FI, cancer survivors (1.9 per 100 person-years for FI ≤ 0.10, 3.4 per 100 person-years for 0.10FI ≤ 0.21, and 7.5 per 100 person-years for FI0.21) had higher mortality than their cancer-free counterparts (1.4 per 100 person-years for FI ≤ 0.10, 2.4 per 100 person-years for 0.10FI ≤ 0.21, and 5.4 per 100 person-years for FI0.21). The multivariable model suggested a positive association between the FI and all-cause mortality for survivors (aHR for FI0.21 vs FI ≤ 0.10, 2.80; 95% CI, 1.73-4.53) and participants without a cancer history (aHR for FI0.21 vs FI ≤ 0.10, 2.75; 95% CI, 2.29-3.32). Restricted cubic splines indicated that all-cause mortality risk increased with the FI in a monotonic pattern.Frailty is associated with a higher risk of death in older cancer survivors and the elderly without a cancer history.