Clin Hypertens.  2019 ;25(1):2. 10.1186/s40885-018-0106-4.

Evaluation of the applicability of deep breathing test in the diagnosis of hypertension with white-coat effect in Chinese patients in primary care

• Chan KS
• Lai KP
• Chan PF
• Luk MH
• Chao VK

• KMID: 2468610
• DOI: http://doi.org/10.1186/s40885-018-0106-4

Abstract

PURPOSE
The current gold standard for the diagnosis of white-coat effect is by the 24-h ambulatory blood pressure monitoring (ABPM) which may not be readily available in every primary care setting. Previous studies had shown that deep breathing, through modulating the baroreceptor reflex sensitivity to vagal stimulation over 30 to 60"‰s, was useful in detection of the white-coat effect. The aim of our study was to evaluate the diagnostic accuracy of the deep breathing test (DBT) as compared with the gold standard of ABPM in the diagnosis of hypertension with white-coat effect in Chinese patients in primary care.
METHODS
This cross sectional study recruited 178 consecutive, eligible, consented, hypertensive patients receiving treatment at a local public primary care Hypertension Clinic. The diagnostic accuracy of the DBT in all recruited patients, patients not taking beta-adrenergic blockers and patients with different clinic SBP cut-off before the DBT by means of area under the receiver operating characteristic (ROC) curve, sensitivity, specificity, positive and negative predictive values was evaluated.
RESULTS
The results for the ROC curves for systolic and diastolic BP changes after the DBT were statistically insignificant. The ROC curve was statistically significant for SBP change in patients not taking beta-adrenergic blockers and with pre-DBT clinic SBP"‰â‰¥"‰165"‰mmHg (ROC curve area of 0.719, 95% CI 0.53 to 0.91, p"‰="‰0.04). The corresponding sensitivity and specificity of the DBT were 40.9 and 90.9% respectively if SBP drop was >"‰30"‰mmHg.
CONCLUSION
The DBT, even though could not be clinically applied to all patients, was proven to be a potential screening and diagnostic test for white-coat effect in Chinese hypertensive patients with a pre-test SBP of ≥165"‰mmHg and who were not taking beta-adrenergic blockers. TRIAL REGISTRATION: This study was approved by Kowloon East Cluster/ Kowloon Central Cluster Research Ethics Committee/Institutional Review Board of Hospital Authority of Hong Kong under the registration KC/KE-16-0084/ER-3.

Keyword

White-coat effect; Deep breathing test; Hypertension; Primary care

MeSH Terms

Adrenergic beta-Antagonists
Asian Continental Ancestry Group*
Baroreflex
Blood Pressure Monitoring, Ambulatory
Diagnosis*
Diagnostic Tests, Routine
Ethics, Research
Hong Kong
Humans
Hypertension*
Mass Screening
Primary Health Care*
Respiration*
ROC Curve
Sensitivity and Specificity
Adrenergic beta-Antagonists