Racial Differences and US population estimates of Nocturnal Hypertension and Non-dipping

1. SPECIFIC AIMS 1.A. AIM 1 To determine racial differences in abnormal diurnal blood pressure (BP) patterns, including nocturnal hypertension and a non-dipping BP pattern. Racial differences in the correlates of abnormal diurnal BP patterns will also be examined. Hypothesis 1.1: Nocturnal hypertension and non-dipping BP will be more common among African Americans compared with whites. Hypothesis 1.2: Modifiable risk factors including stress, obesity, and sleep disordered breathing will be associated with a higher prevalence of nocturnal hypertension and non-dipping BP in African Americans and whites. 1.B. Aim 2. To determine the association between healthy lifestyle factor trajectories over 30 years with the subsequent risks of nocturnal hypertension and a non-dipping BP pattern. Hypothesis 2.1: Maintenance of healthy lifestyle factors from young adulthood through middle age will be associated with a lower prevalence of nocturnal hypertension and non-dipping BP pattern. 1.C. Aim 3. To determine associations of nocturnal hypertension and non-dipping BP patterns with target organ damage. We will also determine whether these associations differ by race. Hypothesis 3.1: Nocturnal hypertension and a non-dipping BP pattern will be associated with greater hypertension-related sub-clinical CVD including left ventricular mass, impaired left ventricular diastolic and systolic function and a higher prevalence of chronic kidney disease (CKD). These associations will be independent of clinic BP and stronger for African Americans than for whites. 1.D. Aim 4. To estimate the prevalence and number of US adults with nocturnal hypertension and non-dipping BP. We will also estimate the economic costs and benefits of screening for these phenotypes in US adults and the cost-effectiveness of treating nocturnal hypertension and non-dipping BP. Hypothesis 4.1: The estimated US population burden of non-dipping BP and nocturnal hypertension will be high, particularly among African Americans. Adding this information will re-categorize many people with “controlled” clinic BP as having “uncontrolled” nocturnal BP. Hypothesis 4.2: Using ABPM screening to identify nocturnal hypertension and non-dipping BP will be cost effective from a payer and patient perspective, overall, and for African Americans and whites.