1. ¹Department of Medicine and Aging Science, University 'Gabriele d'Annunzio', Chieti, Italy
2. ²Department of Biomedical Science, University 'Gabriele d'Annunzio', Chieti, Italy
3. ³Clinical Research Center, University 'Gabriele d'Annunzio' Foundation, Chieti, Italy

Correspondence: Professor SD Pierdomenico, Medicine and Aging Science, Patologia Medica, Policlinico 'Santissima Annunziata', University Gabriele d'Annunzio, Via dei Vestini, Chieti Scalo (Chieti), 66013, Italy. E-mail: pierdomenico@unich.it

Received 1 November 2007; Revised 11 January 2008; Accepted 12 January 2008; Published online 21 February 2008.

Abstract

The prognostic impact of white-coat hypertension is not yet completely clear. In this study, we investigated cardiovascular outcome in sustained hypertension, white-coat hypertension and normotension in the short and long term. The occurrence of fatal and nonfatal cardiovascular events was evaluated in 1732 subjects with clinical hypertension (1333 with sustained and 399 with white-coat hypertension) and 305 with normotension. White-coat hypertension was defined as clinical hypertension and daytime blood pressure <135/85 mm Hg. During the period of observation (mean 6.4 years, range 0.7–13.1), 152 cardiovascular events occurred. The event rate per 100 patient-years in subjects with normotension, white-coat and sustained hypertension was 0.38, 0.44 and 1.58, respectively. Event-free survival was significantly different among the groups (P<0.0001). After adjustment for several covariates, Cox regression analysis showed that cardiovascular risk was significantly higher in patients with sustained than in those with white-coat hypertension (relative risk (RR) 3.32, 95% confidence interval (CI) 1.81–6.12, P=0.0001), whereas there was no significant difference between normotension and white-coat hypertension. When events were analysed separately, cardiac and cerebrovascular risk were significantly higher in sustained than in white-coat hypertension (RR 4.16, 95% CI 1.48–11.6, P=0.007, and RR 4.12, 95% CI 1.62–10.5, P=0.003, respectively) and not significantly different between white-coat hypertension and normotension. Event-free survival had the same trend for the whole period of observation both when cardiovascular events were examined together and when cardiac and cerebrovascular events were analysed separately. In this study, cardiovascular risk in white-coat hypertension was significantly lower than that in sustained hypertension and not significantly different from normotension both in the short and long term.