Hormone Therapy Linked to Lower Dementia Risk in Patients With Breast Cancer

According to a study in JAMA Network Open, patients with breast cancer who received hormone-modulating therapy (HMT) had a reduced risk of Alzheimer disease and related dementias (ADRD), with the effect varying according to age and race.

This cohort study included data from 18,800 women aged 65 years and older who were diagnosed with breast cancer between 2007 and 2009. The majority (87.9%) of participants were White, 6.7% were Black, and 5.4% identified as another race. Two-thirds of patients received HMT within 3 years of diagnosis.

During an average follow-up period of 12 years, 23.7% of  HMT users and 27.9% of non-HMT users developed ADRD. HMT was associated with a 7% lower relative risk of ADRD overall (P=.005). The association between HMT and protection against ADRD decreased with age and varied by race. The strongest effect was found in women aged 65 to 74 years who identified as Black (hazard ratio [HR], 0.76; 95% CI, 0.62-0.92). This effect decreased by ages 75 and older (HR, 0.81; 95% CI, 0.67-0.98). White women aged 65 to 74 years had an 11% relative risk reduction (HR, 0.89; 95% CI, 0.81-0.97), dropping to a 4% reduction in White women aged 75 years and older (HR, 0.96; 95% CI, 0.90-1.02). However, the authors noted that other races did not demonstrate a significant association between HMT use and risk of ADRD. HMT type also influenced ADRD risk.

Based on these findings, the authors advised, “When deciding to use HMT for breast cancer in women aged 65 years or more, clinicians should consider age, self-identified race, and HMT type in treatment decisions.”