White coat effect and masked uncontrolled hypertension in treated hypertensive-diabetic patients: Prevalence and target organ damage.

Background: The association between hypertensive phenotypes of controlled hypertension (CH), white-coat effect (WCE), masked uncontrolled hypertension (MUH) and sustained hypertension (SH) with target organ damage have not been clearly established in diabetic hypertensive treated patients. The present study aims to evaluate the prevalence of the four phenotypes considering the current cut-off points for office and 24 h-ambulatory blood pressure monitoring (ABPM) and the association with left ventricle hypertrophy (LVH), diastolic function and nephropathy.

Methods: Cross-sectional study with 304 patients on anti-hypertensive treatment aged 57.6 ± 6.1 years, who were submitted to ABPM and echocardiography. They were classified into CH (normal office BP and ABPM), WCE (high office BP and normal ABPM), MUH (normal office BP and high ABPM), and SH (high office BP and ABPM).

Results: Median HbA1c and diabetes duration were 7.9% (6.8-9.2), and 10 years (5-16), respectively. Prevalences of CH, WCE, MUH and SH were 27.3%, 17.1%, 18.8%, and 36.8%. MUH prevalence was higher than previously described. There was a significant increasing trend across the four groups in variables related to LVH (P < 0.001 for trend). There was not a clear "dose-response" relationship of the four hypertensive phenotypes with nephropathy and diastolic function.

Conclusion: The use of ABPM beyond the traditional cardiovascular risk stratification tools has limitations, but is still useful in high-risk patients. Longitudinal studies could better evaluate the role of the use of ABPM in this scenario. Cut-off points for normality of office and ABPM influence the prevalences of WCH and MUH.