Multi-systemic biological risk (MSBR), a proxy for allostatic load, is a composite index of biomarkers representing dysregulation due to responses to chronic stress. this study examined the association of an MSBR index with cancer mortality. the sample included n = 13,628 adults aged 20-90 from the NHANES III Linked Mortality File (1988)(1989)(1990)(1991)(1992)(1993)(1994). The MSBR index included autonomic (pulse rate, blood pressure), metabolic (HoMA ir , triglycerides, waist circumference), and immune (white blood cell count, C-reactive protein) markers. We fit Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CI) of overall cancer mortality risk, according to quartiles (q) of the index. In multivariable models, compared to those in q1, q4 had a 64% increased risk for cancer mortality (HR = 1.64, 95% CI:1.13-2.40). The immune domain drove the association (HR per unit = 1.19, 95% CI:1.07-1.32). In stratified analyses, the HR for those with a BMI ≥ 25 was 1.12 per unit (95% CI:1.05-1.19) and those with a BMI < 25 was 1.04 per unit (95% CI:0.92-1.18). MSBR is positively associated with risk for cancer mortality in a US sample, particularly among those who are overweight or obese.
The utilization of standard clinical measures comprising this index may inform population cancer prevention strategies.Multi-systemic biological risk (MSBR) is a proxy for allostatic load (AL). It is a metric of health risk that captures the complex biological cascade that occurs in autonomic, metabolic, and immune domains in response to chronic environmental and psychosocial stress 1-3 . The validity of the AL construct is established and demonstrates common variance and statistical coherence between, prominent primary mediators of the stress response (i.e., stress hormones), and secondary mediators reflecting the resulting biological alterations in autonomic, metabolic, and immune domains that accumulate over time [4][5][6][7][8] . Importantly, summary AL indices have demonstrated a non-additive, stronger magnitude of association with outcomes compared with the individual components of the index 9 .Previous research has shown that autonomic, metabolic, and immune disorders, share common risk factors with cancer outcomes 10-12 . Moreover, there is a strong physiological link between over-activation of the stress response and regulation of the tumor microenvironment [13][14][15] . In mechanistic animal studies where stress can demonstrably be reproduced, chronic responses to stress influence processes involved in tumorigenesis [16][17][18][19] . However, observational studies assessing self-report of stressful life events and cancer outcomes have generally been inconsistent [20][21][22][23][24][25] .Epidemiological studies show positive associations between higher levels of AL indices and cardiovascular disease (CVD), as well as mortality risk 26,27 . However, we are not aware of any studies that have examined an index of AL with cancer outcomes. With cancer being the second leading cause of de...