March 22, 2021

Chemo for cancer lowers dementia risk

Cancer chemotherapy lowered risk of Alzheimer’s disease and other neurocognitive disorders that disproportionately affect older people.

by Paul Govern

Chemotherapy lowers risk of Alzheimer’s disease (AD) diagnosis by approximately 21%, and similarly lowers risk of diagnoses for most other major neurocognitive disorders that disproportionately affect older people 

That’s according to a study reported in JCO Oncology Practice by Miklos Kertai, MD, PhD, and colleagues. The team studied administrative records from 135,834 Medicare beneficiaries ages 65 and older who were diagnosed with colorectal cancer between 1998 and 2007. Around 38% received chemotherapy. To adjust for other patient variables tracked in the study, the team used a method called inverse probability weighting.  

Statistically speaking, chemotherapy’s AD risk-lowering effect dwindled to nonsignificance within six years. The study also found that the impacts of chemotherapy on AD risk varied between specific chemotherapy medications 

The authors note that, while a survey of the research literature yields inconsistent findings regarding the effects of chemotherapy on cognitive function and neurodegenerative dementiacancer medications are increasingly under study as potential new therapies for AD.

Kertai worked on the study with colleagues at Duke University, including lead author Igor Akushevich, PhD. The study was supported by the National Institutes of Health (AG066133AG046860).