Association of Allostatic Load and All Cancer Risk in the SWAN Cohort

Abstract

Elevated chronic stress is thought to increase cancer risk, though the results so far have been inconsistent. In this study, we assessed the relationship between allostatic load (AL), a biological indicator of chronic stress, and overall cancer risk in 3015 women who participated in the Study of Women’s Health Across the Nation (SWAN). Based on the distribution of AL, the study population was categorized into four groups, from the lowest (1st category) to the highest AL group (4th category). At baseline, African American and Hispanic women were more likely to be in the higher AL categories than White women (p < 0.001). In addition, women who smoked regularly, drank alcohol regularly, had no leisure physical activity, and had restless sleep were also more likely to be in the higher AL categories than their relative counterparts (p < 0.001). We also observed that women in the lower-income category with no health insurance were more likely to be in the higher AL category (p < 0.001). The study then found that women in the 4th category of AL (the highest AL group) had a 1.64-fold increased risk of overall cancer (Hazard ratio (HR): 1.64, 95% confidence interval (CI): 1.04, 2.59). The risk association was further strengthened after adjusting demographics, healthy behaviors, and socioeconomic factors with an HR of 2.08. In further analysis of individual biomarkers of AL score, we found that higher levels of triglyceride and CRP were associated with increased risk of cancer, highlighting the role of metabolic dysfunction and inflammation in the etiology of cancer development. In summary, we report that higher AL is associated with increased cancer risk.

Addressing differences in cancer: a framework for synergistic programming in cancer prevention and control

“…First, we underscore biological (e.g., family risk) and behavioral (e.g., substance abuse and physical activity) risk factors that co-occur, as visually represented on our framework by the circular arrows in the risk factors domain. In turn, these risk factors can produce biological and physiological changes that create a "wear and tear" on the body (allostatic overload) that can increase risk for cancer diagnosis and negatively impact cancer survivors [49][50][51][52]. Second, our framework describes how cancer diagnosis and survivorship vary by multiple characteristics and determinants.…”

Daily spiritual experiences and allostatic load trajectories: a longitudinal study of midlife African American women

“…Thus, a higher AL score is indicative of a greater physiologic burden from prolonged exposure to stress 2-4 . This approach has been used in prior studies to assess AL; 26,27 this analysis included AL scores measured annually at seven time points (baseline [1996-1997] thru visit 7 [2003-2004]). AL scores could not be calculated at the second follow-up visit because total cholesterol, HDL-C, triglycerides, glucose, and CRP were not assessed.…”

Cadmium, Lead, Chronic Physiological Stress and Endometrial Cancer: How Environmental Policy Can Alter the Exposure of At-Risk Women in the United States

“…Cancer risk factors, such as environmental toxicants, have long been postulated to include the increased "wear and tear" on the body driven by prolonged stress [67] and by inhibiting the production and absorption of estrogens which reduce the uterus' sensitivity to estrogen stimulation, and psychological stress may increase the likelihood of endometrial cancer [68].…”

“…The Allostatic Load (AL), an index of chronic stress, is a multi-system, multi-dimensional composite measure that typically includes cardiovascular, metabolic, immunological, and neuroendocrine components and has been shown to be a suitable measure of the adverse consequences of prolonged stress levels on health [69]. Compared to many other stress evaluation metrics, AL considers the biological impact of cumulative stress and takes into consideration people's responses and reactions to the stress burden [67]. Numerous negative effects can result from prolonged exposure to stress, including sleep disturbances and insomnia [70], endocrine abnormalities [71] and alterations in the immune system [72], leading to an increased tendency of tumor production [73] as the immune system has a specific function in predisposing the initiation and advancement of tumor growth through cancer-promoting inflammation [74].…”