Smoking and overweight associated with masked uncontrolled hypertension: a Hypertension Optimal Treatment (HOT) Sub-Study.

Purpose: The Hypertension Optimal Treatment (HOT) Study investigated the relationship between target office diastolic blood pressure (BP) ≤80, ≤85 or ≤90 mmHg and cardiovascular morbidity and mortality in 18,790 patients aged 50-80 years. The home BP sub-study enrolled 926 patients and the aim was to clarify whether the separation into the BP target groups in the office prevailed in the out-of-office setting. The present study aimed to identify variables that characterised masked uncontrolled hypertension (MUCH) and white coat uncontrolled hypertension (WUCH).
Material and Methods: The sub-study participants took their home BP when office BP had been up titrated. The cut-off for normal or high BP was set to ≥135/85 mmHg at home and ≥140/90 mmHg in the office. We analysed data by using multivariate and stepwise multivariate logistic regression with home and office BP combinations as the dependent variables.
Results: WUCH was associated with lower body mass index (BMI) (odds ratio (OR) 0.92, 95% confident intervals (CIs) 0.88-0.96, p  < 0.001). MUCH was associated with smoking (OR 1.89, 95% CIs 1.25-2.86, p  = 0.0025) and with lower baseline heart rate (OR 0.98, 95% CIs 0.97-0.99, p  = 0.03) and higher BMI (OR 1.03, CIs 1.00-1.06, p  = 0.04). MUCH remained associated with smoking (OR 2.76, 95% CIs 1.76-4.35, p  < 0.0001) also when using ≥140/90 mmHg as the cut-off for both home and office BP. MUCH was also associated with higher BMI (OR 1.05, 95% CIs 1.01-1.09, p  = 0.009) while WUCH was associated with lower BMI (OR 0.93, 95% CIs 0.90-0.97, p  = 0.0005) when using ≥140/90 mmHg as a cut-off.
Conclusion: Our data support that 'reversed or masked' treated but uncontrolled hypertension (MUCH) is common and constitutes about 25% of treated hypertensive patients. This entity (MUCH) is rather strongly associated with current smoking and overweight while uncontrolled white coat (office) hypertension (WUCH) is associated with lower BMI.