Effort-reward imbalance, heart rate, and heart rate variability:: The cardiovascular risk in Young Finns Study

Background: Work stress indicated by effort-reward imbalance is hypothesized to cause autonomic arousal, which, if prolonged or frequent, could contribute to cardiovascular pathology. However, only limited empirical evidence on this mechanism is available. Purpose: This study examined associations between effort-reward imbalance, heart rate (HR), and heart rate variability (HRV). Method: The participants were 457 women and 406 men (mean age 32.3 years) derived from the population-based Young Finns Study. Effort-reward imbalance was defined as the ratio between effort and reward, higher efforts compared to rewards indicating greater imbalance. Results: In age-adjusted regression models, higher effort-reward imbalance was associated with lower HRV and lower reward was associated with higher HR among women. These associations were not attenuated after additional adjustments for demographic characteristics and coronary risk factors. No significant associations of effort-reward imbalance or its components with HR and HRV were found in men. Conclusion: Our finding of lower HRV and higher HR in young healthy women with high effort-reward imbalance and low rewards provides evidence of a potential mechanism that may link effort-reward imbalance to the development of coronary heart disease (CHD) in women.