HDCN Article Review/Hyperlink

Glen SK, Elliott HL, Curzio JL, Lees KR, Reid JL

White-coat hypertension as a cause of cardiovascular dysfunction

Lancet (Sep) 348:654-657 1996

This is another cross-sectional study which tries to address the issue of whether white-coat hypertension is an innocuous condition. Although most of the available study indicate that it is likely to be benign in the short term, several groups have suggested that such patients are truly hypertensive.

Study design
The authors matched three groups of subjects acording to age, sex and other demographics. They defined the groups as follows: 

Group
                   Office BP (mmHg)         Daytime BP (mmHg)
Normotensive        < 95                         < 95
White-coat          > 95                         < 95
Hypertensive        > 95                         > 95


They then studied diastolic function of the heart (correcting for BP at the time of measurement) as well as large artery compliance (also corrected). All subjects had to be off antihypertensive therapy for at least 4 weeks.

Results
The results showed that left ventricular mass was similar in normotensives as in white-coat hypertensives and lower than sustained hypertensives. They also found that the E/A ratio was lower in both white-coat and sustained hypertensives than in normotensives. They also found that there was reduced arterial elasticity in the white-coat and hypertensive groups compared to the normotensive groups.

Comment: The value of this study is limited by the definition used by the authors of the three groups. It is clear that the patients included in the white-coat group would be considered hypertensive (e.g. office DBP 96 mmHg and daytime DBP 94 mmHg) by many observers and treated and that the normotensive group also may include patients that would be labeled hypertensive (e.g. office DBP 94 mmHg, daytime DBP 94 mmHg). Unfortunately, clear separation of the three groups was not attained. Furthermore, the effects of recent antihypertensive therapy on arterial elasticity and diastolic function need to be accounted for. Thus previous therapy is a potential confounder in this study since patients were only off antihypertensive therapy for four weeks. The findings in this study re-emphasize that a consensus is needed about the definition of white-coat hypertension. The present study could have found entirely different results if the three groups were better separated. (George Mansoor, M.D., University of Connecticut)

The full text of this abstract is available at the Lancet site. The first time you access the Lancet site, you will need to register to get a login ID and password. Then you can read the full text full text.

Accompanying this paper for print in pdf.