OLDER adults diagnosed with hematologic malignant neoplasms (HMN) experience cognitive decline at a rate similar to normal aging, even after diagnosis, when adjusting for the competing risk of death, according to recent research.
With an increasing number of older adults surviving long-term after HMN diagnoses, there is a growing need to understand the impact of HMN on cognitive function. While cognitive impairment has been documented in other cancers, limited data are available regarding cognitive outcomes in older adults with HMN. This study aims to compare the cognitive trajectories of older adults with HMN to a matched cohort of older adults without cancer to inform patient counselling and management strategies.
This population-based cohort study analysed data from the Health and Retirement Study (HRS), identifying 668 older adults diagnosed with HMN between 1998 and 2016, who were matched 1:3 to 1,994 participants without cancer, using propensity scores. Cognitive function was measured using the Langa-Weir cognitive summary score, with cognitive trajectories modelled over time using piecewise linear splines. The study compared rates of cognitive decline before, during, and after diagnosis in both groups, adjusting for sociodemographic and health-related factors. Results showed that before diagnosis, and in the two years surrounding diagnosis, both groups exhibited similar rates of cognitive decline. One year after diagnosis, cognitive decline in the HMN cohort was initially slower (−0.18; 95% CI: -0.23 to -0.14 compared to -0.24; 95% CI: -0.26 to -0.23; p=.02, but this difference became nonsignificant after accounting for the competing risk of death (-0.27; 95% CI: -0.34 to -0.19, and, -0.30; 95% CI: -0.33 to -0.27; p=.48).
The findings of this study suggest that older adults with HMN have cognitive trajectories comparable to those of individuals experiencing normal aging, even after diagnosis. From a clinical perspective, this is significant as it suggests that a diagnosis of HMN alone may not accelerate cognitive decline. Future research should explore the cognitive effects of different HMN treatments, such as chemotherapy, and assess other potential risk factors for cognitive impairment to better guide clinical management and support patient counselling.
Katrina Thornber, EMJ
Reference
Huang LW et al. Cognitive trajectories in older adults diagnosed with hematologic malignant neoplasms. JAMA Netw Open. 2024;7(8):e2431057.
