Affective Responsivity and Cardiovascular Stress Reactivity in Depression

Profound stress system dysfunction is a hallmark pathological feature of major depressive disorder (MDD), including altered affective dynamics in response to stress. However, no studies have directly assessed the link between negative affective responsivity (NA-R) to daily stressors and sympathetic-cardiovascular stress reactivity in young adults with MDD. We tested the hypotheses that (1) greater NA-R to daily stressors would be positively related to the magnitude of acute stress-induced sympathetic-cardiovascular reactivity in young adults (18-30 years) and (2) the slope of these relations would be steeper in young adults with MDD (unmedicated) compared with nondepressed healthy adults.

Daily stress processes and affective dynamics were assessed during routine everyday life for 8 consecutive days in 42 nondepressed healthy adults and 39 adults with MDD (daily diary). On the last day of the daily assessments, heart rate (ECG), beat-to-beat blood pressure (finger photoplethysmography), and muscle sympathetic nerve activity (peroneal microneurography) were measured during the cold pressor test, a standard laboratory stressor.

NA-R to daily stressors was amplified in MDD adults (P=0.01). Greater NA-R was related to larger acute stress-induced increases in heart rate only in MDD adults (b=48.61 [95% CI, 22.48-74.74]) but not in nondepressed healthy adults (b=-6.81 [95% CI, -41.95 to 28.33]). NA-R to daily stressors was not related to blood pressure or muscle sympathetic nerve activity reactivity in either group (all P>0.05).

These data suggest that the association between NA-R to daily stressors and cardiovascular reactivity to stress is sensitized in young adults with MDD, potentially contributing to future cardiovascular disease risk.