NEW YORK (Reuters Health) – Long-term exposure to chronic social and environmental stress may contribute to poor outcomes in women with breast cancer, new research suggests.
The study found that chronic physiologic “wear and tear” from lifelong exposure to stressors, known as allostatic load, was associated with a decreased likelihood of completing chemotherapy and a lower overall survival in women with lymph node-positive or high-risk node-negative HER2-negative breast tumors.
“Allostatic load appeared to be a better predictor of chemotherapy completion and overall survival than genetic ancestry,” said Dr. Samilia Obeng-Gyasi of The Ohio State University Comprehensive Cancer Center, in Columbus, in presenting the results at the 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved.
Chronic exposure to stressors, such as social isolation, poverty, and racism, have been linked to various health problems, including high blood pressure, increased body weight, kidney disease, inflammation, arthritis, and other conditions. These chronic stressors are more common among racial/ethnic minority groups, she explained.
The researchers assessed the impact of allostatic load or genetic ancestry (identified by DNA) on the likelihood of completing chemotherapy and survival in women with breast cancer.
They used data from the ACOG-ACRIN E5103 trial evaluating the inclusion of bevacizumab into adjuvant sequential anthracycline and paclitaxel in women with lymph node-positive or high-risk lymph node-negative HER2-negative breast cancer.
Allostatic load at trial entry was comprised of the biomarkers of BMI, blood pressure, creatinine, interleukin-6, interleukin-10, and tumor necrosis factor-alpha. Logistic regression and Cox proportional hazards models were used to assess the association between allostatic load and genetic ancestry on chemotherapy completion and overall mortality. Estimates for allostatic load were adjusted for genetic ancestry.
The analysis included 348 women; 80% had European ancestry, 10% had African ancestry, and 10% had other ancestry. Women of African and European ancestry had a higher allostatic load at study entry than women of other ancestry.
Women with a high allostatic load at the beginning of the study had a greater likelihood of stopping chemotherapy early and a higher risk of death, Dr. Obeng-Gyasi reported.
After adjusting for genetic ancestry, each one unit increase in allostatic load score was associated with a 15% reduction in the likelihood of completing chemotherapy and a 14% increase in the risk of dying.
“Notably, there was no interaction between allostatic load and genetic ancestry,” Dr. Obeng-Gyasi said in her presentation.
“These results suggest life course exposure to chronic stress has implications on clinical outcomes even within the context of equivalent access to and quality care,” she added.
With further research, measuring allostatic load may be a useful tool to identify women with breast cancer who may be at increased risk for stopping chemotherapy early or having poor survival, Dr. Obeng-Gyasi said.
“Future prospective clinical trials with repeated measures of allostatic load may provide greater insight into its relationship to treatment and survival, especially if allostatic load is collected multiple times during the active treatment and survivorship phases of care,” she said in a conference statement.
SOURCE: https://bit.ly/3FtWpTJ AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved, presented October 6, 2021.
Source: Read Full Article