Occupational stress and cardiovascular reactivity in blue-collar workers

This study analyses the influence of chronic occupational stress on cardiovascular reactivity (heart rate [HR] and blood pressure [BP] elevation from baseline to maximal challenge) during a standard mental stress test (modified version of the STROOP colour word interference test). The test was applied to a sample of 190 healthy male blue-collar workers at the end of a regular working day. Our research hypothesis was based on the assumption that sustained autonomic activation due to chronic occupational stress may reduce cardiovascular responsiveness to challenge: workers defined by high level of chronic occupational stress exhibited lower maximal HR and BP elevations under challenge as compared to workers with low levels of stress. Three distinct indicators of occupational stress were derived from structured interviews: ‘cumulative workload’, ‘worsening of job conditions', and ‘high demand and low job security’. Statistical analysis, using ANOVA, showed that all main effects of chronic stress were in the expected direction (6 of 9 effects were statistically significant at the 0'05 level). These effects remained stable after adjusting for age, hypertensive status, physiological baseline level, cigarette smoking, test performance, and individual style of coping. In summary, cardiovascular reactivity under experimental challenge is modulated by an individual's experience of chronic occupational stress.