Long-Term Cognitive Side Effects of Adjuvant Chemotherapy for Breast Cancer

A recent study published in Medical Oncology has shed light on the long-term cognitive side effects of adjuvant chemotherapy for breast cancer. Researchers from the University of Texas examined the incidence of dementia diagnoses in older women diagnosed with breast cancer, stratified by types of chemotherapy regimen. The study found that increasing age at cancer diagnosis, Black ethnicity, living in a census tract with lower level of education, and increasing number of comorbidities were associated with new claims of dementia diagnoses after chemotherapy. However, no significant association was found between types of chemotherapy agents and risk of subsequent dementia diagnoses.

Key Takeaways:

• The study examined the incidence of dementia diagnoses in 6,932 older women diagnosed with breast cancer in one of the SEER areas from 1994 through 2002.
• The study found that 57% of the participants were estrogen receptor positive, and over 70% had no comorbidity.
• Increasing age at cancer diagnosis, Black ethnicity, living in a census tract with lower level of education, and increasing number of comorbidities were associated with new claims of dementia diagnoses after chemotherapy.
• No significant association was found between types of chemotherapy agents and risk of subsequent dementia diagnoses.
• The researchers concluded that concerns about post-chemotherapy dementia should not be a major factor in determining type of adjuvant chemotherapy regimen to prescribe for older women with breast cancer.
• The study excluded women with a diagnosis of dementia within the 3 years prior to their cancer diagnosis.

Statistics:

• 6,932 women aged 68 years or older were included in the study.
• 57% of the participants were estrogen receptor positive.
• Over 70% of the participants had no comorbidity.
• The study found that 71.2% of patients received taxol-based treatment, while 23.2% received anthracycline-based treatment.
• The increasing age at cancer diagnosis was associated with a 25% increased risk of subsequent dementia diagnoses.
• Black ethnicity was associated with a 35% increased risk of subsequent dementia diagnoses.

Sources:

• M.A. Raji et al., "Risk of subsequent dementia diagnoses does not vary by types of adjuvant chemotherapy in older women with breast cancer." Medical Oncology, 2009;26(4):452-459.
• University of Texas, School of Medicine, Department of Internal Medicine. (Contact information: M.A. Raji, University of Texas Med Branch, Dept. of Internal Medical, Sealy Center Aging, 301 University Blvd., Rt 0460, Galveston, TX 77555, USA).
• Humana Press Inc., 999 Riverview Drive Suite 208, Totowa, NJ 07512, USA.