Research Project
9411178
PROJECT SUMMARY Hypertension (HTN) affects approximately 33% of all adults living in the United States, particularly African Americans, who comprise over 42% of those with HTN [1-2]. In aging, HTN is associated with decreased cognitive functioning, and increased risk for clinically meaningful cognitive impairments and incident age-related neurodegenerative disorders [3-4]. HTN may confer risk for cognitive impairment via alterations in cerebral autoregulation (CA) caused by structural and functional changes to the cardiac and cerebral vasculature induced by HTN [5]. The impact of HTN on cognitive functioning in diverse, aging persons living with HIV (PLWH), however, is largely unknown, especially whether HTN differentially affects cognitive outcomes in HIV+ African Americans. Work in the cognitive aging literature suggests that HTN has a greater impact on cognitive functioning among African Americans than Latinos and non-Hispanic Whites [6]. One possible explanation for these differences may be due to disparities in HTN control that disproportionately affect African Americans [7-8]. As a result, we hypothesize that with aging, HTN as well as poor HTN control will exacerbate cognitive impairment in PLWH and that this effect will be greatest among African Americans. Therefore, the first aim of this study is to examine the longitudinal relationship between HTN and cognitive functioning in a diverse cohort of aging PLWH to examine the effects of HTN and HTN control on risk for cognitive impairments. These data will also be used to examine for racial disparities in the rates of cognitive impairment in this cohort. Finally given our limited understanding of the biological effects of HTN on brain functioning and cognition, the third aim of this study is to evaluate the longitudinal relationship between pulse pressure (PP), a surrogate marker of arterial stiffness, and cognition to indirectly explore the biological consequences of hypertension on the brain and CA [9]. Investigations regarding the potential impact of HTN, HTN control and PP on the brain and cognitive functioning are relevant given the increasing prevalence of HTN in aging PLWH, especially among HIV+ African Americans who currently comprise 50% of all HIV cases in the U.S. and experience greater hypertension burden [10]. Therefore, this project is both highly novel and significant as it will be the first to examine the longitudinal relationships between HTN, HTN control, PP and cognition in an exceptionally well- characterized and diverse sample with extensive longitudinal outcomes. Improved understanding of the role of HTN and HTN control on cognitive functioning in diverse, aging PLWH is critical to elucidate sources of health disparities frequently affecting underrepresented minority populations (URM). Thus, the results of this project also have important implications for public health, as this study will provide empirical evidence to inform and develop targeted intervention strategies that may mitigate cognitive dysfunction in URM.
