Ambulatory blood pressure monitoring elicited a significant pressor response on the first day compared to the second day (P<0.001), which diminished but persisted in successive sessions.
Observational (n=823)
Does ambulatory blood pressure monitoring induce a pressor effect during initial and successive sessions in mild-to-moderate hypertensive patients?
Ambulatory blood pressure monitoring induces a significant pressor effect lasting up to 10 hours during the first day, which diminishes but persists in subsequent monitoring sessions, highlighting the need to account for this novelty effect in clinical diagnosis and treatment evaluation.
p-value: p=<0.001
Objectives Previous results have indicated that ambulatory monitoring provides a pressor effect on patients using the device for the first time, but not on successive sessions of monitoring. Our objective was to validate and quantify the extent and duration of this pressor effect in hypertensive patients repeatedly evaluated every few months. Methods We studied 823 mild-to-moderate hypertensive subjects (347 men), 53.4 ± 14.1 years of age. Blood pressure was measured at 20-min intervals during the day and at 30-min intervals at night for 48 consecutive hours, and physical activity was simultaneously evaluated every minute with a wrist actigraph. Forty per cent of the patients were evaluated twice or more. Results In patients evaluated for the first time, results indicated a highly statistically significant (P< 0.001) reduction during the second day of monitoring as compared to the first in the diurnal mean of systolic and diastolic blood pressure, but not in heart rate or physical activity. This pressor effect remained statistically significant for the first 10 h of monitoring, independent of gender, day of the week of monitoring, or number of antihypertensive drugs used by the patients. The nocturnal mean of blood pressure was, however, similar between both days of sampling. This ‘ambulatory monitoring effect’ was diminished, although not eliminated, in extent and duration for successive sessions of ambulatory monitoring. Conclusions Ambulatory monitoring for 48 h revealed a statistically significant pressor response that could mostly reflect a novelty effect in the use of the monitoring device. This effect has marked implications in both research and clinical daily practice for a proper diagnosis of hypertension and evaluation of treatment efficacy by the use of ambulatory monitoring.
Calvo et al. (Mon,) conducted a observational in mild-to-moderate hypertension (n=823). Ambulatory blood pressure monitoring vs. Second day of monitoring / successive sessions was evaluated on Reduction in the diurnal mean of systolic and diastolic blood pressure during the second day of monitoring as compared to the first (p=<0.001). Ambulatory blood pressure monitoring elicited a significant pressor response on the first day compared to the second day (P<0.001), which diminished but persisted in successive sessions.