# Impact of Age on Early CAR T‐Cell Therapy Toxicity: A Propensity Score Matching Analysis

## TL;DR

Older adults receiving CAR-T therapy face higher risks of kidney and heart issues but similar overall safety and outcomes compared to younger patients.

## Contribution

This study uses propensity score matching to assess age-related differences in CAR-T toxicity and outcomes.

## Key findings

- Older adults had higher rates of acute kidney injury and cardiac complications compared to younger patients.
- Early mortality and readmission rates were similar across all age groups despite higher non-home discharge rates in older adults.
- CAR-T therapy appears safe for older adults with appropriate monitoring for specific complications.

## Abstract

Despite the growing use of CAR‐T therapy, adults over 65 still receive this treatment less frequently than younger patients.

Using the Nationwide Readmissions Database (2018–2020), we analyzed 2928 CAR‐T recipients, dividing them into young (18–40), middle‐aged (41–65), and older adults (≥ 66). Propensity score matching (caliper of 0.2, 1:1:1 ratio) was performed. We adjusted for the following confounding variables: gender, comorbidities, and social factors including smoking, alcohol use, and illicit drug use.

Older adults had the highest rates of acute kidney injury (11.7% vs. 13.0% vs. 18.1%, p = 0.02) and cardiac complications (2.0% vs. 3.6% vs. 5.4%, p = 0.03). These three different age groups had comparable rates of leukopenia (45.0% vs. 42.7% vs. 39.1%, p = 0.10), infection (41.0% vs. 43.6% vs. 42.1%, p = 0.74), neurotoxicity (6.2% vs. 6.5% vs. 7.7%, p = 0.52), and pulmonary embolism (1.0% vs. 2.9% vs. 2.3%; p = 0.2). Despite the highest rates of non‐home discharge among the older patients (14.0% vs. 7.5% vs. 8.8%), there were no significant differences in early mortality (5.2% vs. 6.2% vs. 6.7%, p = 0.34), 30‐day readmission (23.1% vs. 23.8% vs. 24.4%, p = 0.48), prolonged index hospitalization (96.1% vs. 94.8% vs. 93.6%, p = 0.14), and total length of stay (21.2 days vs. 18.2 days vs. 21.3 days, p = 0.58).

CAR‐T therapy is safe among older adults with close monitoring for cardiac and renal complications.