Figure 1.

Proportion of Atherosclerosis Risk in Communities (ARIC) and Health and Retirement Study (HRS) participants who are and are not in the target population for selected randomized controlled trials (RCTs) of blood pressure management for Alzheimer disease and related dementias (ADRD) prevention. (A) The proportion of ARIC visit-5 participants. (B) Proportion of HRS wave 2006 or 2008 participants who participated in the enhanced face-to-face interview, allowing collection of biomarker and physical measurement data, who are in the target population of selected RCTs of blood pressure management for the prevention of ADRD. Selected RCTs do not require presence of cardiovascular disease, diabetes, or prior stroke for eligibility. Target populations are defined as presented in Table 1. Note: We were unable to estimate proportions in HRS for the Study on Cognition and Prognosis in the Elderly (SCOPE) or Heart Outcomes Prevention Evaluation–3 (HOPE-3), because of the absence of data required for determining target population eligibility; we excluded all persons who were taking antihypertensive medications when evaluating Systolic Hypertension in the Elderly Program (SHEP) criteria (SHEP allowed participation of persons taking antihypertensive medications if they met systolic blood pressure criteria after withdrawal of medication use); we assumed HRS participants younger than 70 years do not have dementia (dementia status is algorithmically defined only for those older than 70 years); and all estimates reflect the proportion in the target population among those with nonmissing data on variables needed to define target population membership. Abbreviations: HYVET-COG, Hypertension in the Very Elderly Trial Cognitive Function Assessment; MRC, Medical Research Council; SPRINT, Systolic Blood Pressure Intervention Trial; SYST-EUR, Systolic Hypertension in Europe.