A comparison of cardiovascular reactivity to laboratory stressors and day-night blood pressure differences assessed by 24-hour ambulatory blood pressure monitoring.
Date of Graduation
Cardiovascular reactivity (CVR) to laboratory stressors and sleep-related blood pressure changes were compared in mild hypertensive (n = 23) and normotensive (n = 30) Caucasian men and women ranging from 30 to 67 years old. None of the participants had a history of cardiovascular disease and hypertensive patients were medication free at the time of cardiovascular reactivity assessment and 24-hr ambulatory blood pressure recording. Cardiovascular reactivity to mental arithmetic and a modified Digit Symbol task and sleep-related attenuations in blood pressure and heart rate were compared using standardized residual change scores. In general, correlations between laboratory assessed CVR and sleep-related attenuations were small and statistically not significant. Closer examination of gender and hypertensive status revealed that the strongest, and statistically significant, correlations were obtained between CVR and sleep-related attenuation of diastolic blood pressure in hypertensive women but not in hypertensive men or normotensive men and women. Hypertensive men and women, and their normotensive counterparts were equally likely to evidence an abnormal diurnal blood pressure pattern of non-dipping defined by a 10% or less reduction during sleep from mean waking level. Sleep-related reduction in blood pressure was related to percent time at work and percent time engaged in a moderate physical activity suggesting that these factors may play a role in the maintenance of this important aspect of diurnal blood pressure variation. The reduction in blood pressure during sleep was independent of waking levels. Implications, limitations, and suggestions for future research are discussed concluding that investigation of the relation between behavioral factors, including CVR to stress, and sleep-related blood pressure attenuation will improve understanding toward the prevention of cardiovascular disease and maintenance of cardiovascular health. This project was funded by the American Heart Association's West Virginia Affiliate grant-in-aid program (grant 93-7854S).
Schauss, Scott Lee, "A comparison of cardiovascular reactivity to laboratory stressors and day-night blood pressure differences assessed by 24-hour ambulatory blood pressure monitoring." (1999). Graduate Theses, Dissertations, and Problem Reports. 9719.