Occupational disparities in physiologic stress among U.S. workers

Introduction
Occupational stress, associated with increased rates of morbidity,has become a serious U.S. worker health issue. Allostatic Load (AL) as a conceptual framework for the cumulative wear and tear on the body caused by physiological responses to stressors may serve as an objective global stress measure. We 1) examine U.S. data for average AL scores and the proportion of high scores by employment type, 40 specific occupational groups, and four broad sectors; and 2) describe the association between job type and AL.

Methods
The National Health and Nutrition Examination Survey (NHANES) conducted by the U.S. National Center for Health Statistics is designed to monitor U.S. health and nutritional status. We used data from the 2003-2004 NHANES for adults (≥ 17 years old) participating in both a comprehensive medical examination and a questionnaire that reported on their occupational status and job type (n=5,328).We developed an AL index guided by the extant literature that included 10 biomarkers. We further categorized participants by employment status, occupational group, as well as by important socio-demographic characteristics.

Results
The proportion of adults with an AL index score of ≥3wassignificantly higher for unemployed (52.3%) than for employed adults (37.6%) with mean AL scores of 2.73 and 2.14 respectively. Blue-collar workers had a higher proportion (39.1%) experiencing greater physiological stress than white-collar (37.4%), farm (36.8%) or service (33.6%) workers. Adults employed in construction (47.0%)and protective service occupations (51.3%) had the two highest mean AL scores. After adjustment for socio-demographic indicators, blue-collar workers were significantly more likely to experience higher physiologic stress relative to white-collar workers. (Adjusted odds ratio, AOR = 1.44; 95% CI [1.09–1.91]).

Discussion
Considering that stress is a modifiable risk factor, workplace intervention efforts at preventing high stress levels among occupations at high risk may be warranted.