Premature aging as an accumulation of deficits in young adult survivors of pediatric cancer

BACKGROUND: We aimed to characterize premature aging as an accumulation of deficits in survivors of pediatric cancer compared with community controls and examine associations with host and treatment factors, neurocognition, and mortality. METHODS: Pediatric cancer survivors (n = 4000, median age = 28.6, interquartile range IQR = 23-35 years; 20 years postdiagnosis: IQR = 15-27), and community participants without a history of cancer serving as controls (n = 638, median age = 32, IQR = 25-40 years) completed clinical assessments and questionnaires and were followed for mortality through April 30, 2020 (mean SD follow-up = 7.0 3.4 years). A deficit accumulation index (DAI) score was calculated from 44 aging-related items including self-reported daily function, psychosocial symptoms, and health conditions. Items were weighted from 0 (absent) to 1 (present and/or most severe), summed and divided by the total yielding a ratio (higher = more deficits). Scores less than 0.20 are robust, and 0.06 is a clinically meaningful difference. Linear regression compared the DAI in survivors and controls with an age*survivor or control interaction. Logistic regression and Cox-proportional hazards estimated the risk of neurocognitive impairment and death. Models were minimally adjusted for age, sex, and race and ethnicity. RESULTS: The adjusted mean DAI among survivors at age 30 years was 0.16 corresponding to age 63 years in controls (33 years premature aging; β = 0.07, 95% confidence interval CI = 0.06 to 0.08; P < .001). Cranial and abdominal radiation, alkylators, platinum, and neurosurgery were associated with worse DAI (P ≤ .001). Higher scores were associated with increased risk of neurocognitive impairment in all domains (P < .001) and increased risk of death (DAI = 0.20-0.35, hazard ratio = 2.80, 95% CI = 1.97 to 3.98; DAI ≥ 0.35, hazard ratio = 5.08, 95% CI = 3.52 to 7.34). CONCLUSION: Pediatric cancer survivors experience clinically significant premature aging. The DAI may be used to identify survivors at greatest risk of poor health outcomes.