The association between allostatic load and lymphedema in breast cancer survivors.

Purpose: Allostatic load, a measure of physiological dysregulation secondary to chronic exposure to socioenvironmental stressors, is associated with 30-day postoperative complications and mortality in patients with breast cancer. This study aimed to examine the association between allostatic load (AL) at diagnosis and development of breast cancer-related lymphedema (BCRL).

Methods: Patients aged 18 years or older who received surgical treatment for stage I-III breast cancer between 2012 and 2020 were identified from The Ohio State University Cancer Registry. AL was calculated using biomarkers from the cardiovascular, metabolic, renal, and immunologic systems. A high AL was defined as AL > median. Logistic regression analyses examined the association between AL and BRCL, adjusting for sociodemographic, clinical, and treatment factors.

Results: Among 3,609 patients, 18.86% (n = 681) developed lymphedema. A higher proportion of patients with lymphedema were Black (11.89% vs. 7.38%, p < 0.0001), Medicaid insured (12.19% vs. 6.97%, p < 0.0001), had stage 3 disease (7.05% vs. 1.57%, p < 0.0001), and had a high AL (53.63% vs. 46.90%, p = 0.0018). In adjusted analysis, high AL was associated with higher odds of developing lymphedema than low AL (OR 1.281 95% CI 1.06-1.55). Moreover, a 1-unit increase in AL was associated with 10% higher odds of lymphedema (OR 1.10, 95% CI 1.04-1.16). There was no statistically significant association between AL and severity of lymphedema (OR 1.02, 95% CI 0.82-1.23).

Conclusion: In this retrospective cohort of breast cancer survivors, high AL at diagnosis was associated with higher odds of developing lymphedema. Future research should elucidate the pathways by which AL influences lymphedema.