The white-coat effect is associated with increased blood pressure reactivity to physical activity.
OBJECTIVE
The aim of this study was to test the hypothesis that blood pressure (BP) reactivity to the stress of a clinic visit, the so-called white-coat effect, is associated with increased BP reactivity to physical activity.


METHODS
Patients referred to our clinic for assessment of hypertension prospectively underwent 24-h ambulatory BP monitoring and simultaneous actigraphy.


METHODS
The difference between mean clinic BP and mean daytime ambulatory BP was considered to be a measure of the white-coat effect. Presence or absence of a white-coat effect (clinic-daytime difference > 0 mmHg) was added to a mixed model regression of BP on mean activity score for the 10-min interval preceding BP measurement.


RESULTS
The group (n = 421) was heterogeneous in age, gender, mean 24-h BP and use of antihypertensive medications. A total of 259 patients had a systolic white-coat effect; for diastolic BP there were 264. Female patients exhibited a significantly larger white-coat effect. Coefficients for the regressions of both systolic and diastolic blood pressure on physical activity levels were significantly higher in those who had a white-coat effect.


CONCLUSIONS
These data suggest increased BP reactivity to activity in those with a white-coat effect. Patients with a prominent white-coat effect may experience greater BP load during normal daily activities as a consequence of increased BP reactivity. In patients with white-coat hypertension, this may contribute to target-organ damage.
Department of Clinical Pharmacology and Therapeutics, National University of Ireland, Cork, Ireland. learya@doctors.org.uk
Andrew C
AC
Leary
Peter T
PT
Donnan
Thomas M
TM
MacDonald
Michael B
MB
Murphy
D000203:Activities of Daily Living; D000328:Adult; D000959:Antihypertensive Agents / Q000627:therapeutic use; D018660:Blood Pressure Monitoring, Ambulatory; D003971:Diastole; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000503:physiopathology* / Q000523:psychology; D007494:Ireland / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D011446:Prospective Studies; D013315:Stress, Psychological / Q000503:physiopathology; D013599:Systole
D000959:Antihypertensive Agents