Abstract TAC200: Negative Affective Responsivity to Daily Stressors and Beat-to-Beat Blood Pressure Variability in Normotensive Young Adults

Introduction: Heightened negative affective responsivity (NA-R) to daily stressors predicts increased cardiovascular disease (CVD)-related morbidity and mortality, but the mechanisms remain incompletely understood. Psychological stress arising from daily life is associated with greater ambulatory blood pressure variability (BPV)—a major contributor to excessive CVD risk. However, no studies have examined the link between NA-R to daily stressors and beat-to-beat BPV or explored potential underlying mechanisms. Hypothesis: We hypothesized that greater NA-R to daily stressors would be positively related to elevated beat-to-beat BPV. Given studies reporting a link between NA-R to daily stressors and chronic sympathetic overactivation, we further hypothesized that greater NA-R to daily stressors would be positively related to augmented beat-to-beat total peripheral resistance (TPR) variability. Methods: Daily stress processes and affective dynamics were assessed during routine everyday life (daily diary) for 8 consecutive days in 81 normotensive young adults (58 female; 22±5 yrs; 115±9/79±10 mmHg). On the last day of daily assessments, beat-to-beat BP (finger photoplethysmography) was measured during 20-min of supine rest. TPR and cardiac output (CO) were estimated using Modelflow. NA-R to daily stressors was operationalized as the intra-individual slope of the change in negative affect on stressor days compared to stressor-free days (multilevel modeling). Results: Negative affect was greater on stressor days compared to stressor-free days (0.7±0.4 vs. 0.4±0.4; p<0.01), providing evidence of NA-R to daily stressors. NA-R to daily stressors was positively related to BPV (e.g., mean arterial pressure coefficient of variation; b =4.1, SE=1.9; p=0.03) but was not related to either TPR ( b =1.3, SE=3.3; p=0.69) or CO variability ( b =1.5, SE=2.8; p=0.59). Conclusions: These data suggest that amplified NA-R to daily stressors may be associated with elevated beat-to-beat BPV, thereby potentially contributing to increased daily stress-related CVD risk.