Faculty Bibliography

Increasing evidence links cognitive-decline and Alzheimer's disease (AD) to various sleep disorders, including obstructive sleep apnea (OSA). With increasing age, there are substantial differences in OSA's prevalence, associated comorbidities and phenotypic presentation. An important question for sleep and AD researchers is whether OSA's heterogeneity results in varying cognitive-outcomes in older-adults compared to middle-aged adults. In this review, we systematically integrated research examining OSA and cognition, mild cognitive-impairment (MCI) and AD/AD biomarkers; including the effects of continuous positive airway pressure (CPAP) treatment, particularly focusing on characterizing the heterogeneity of OSA and its cognitive-outcomes. Broadly, in middle-aged adults, OSA is often associated with mild impairment in attention, memory and executive function. In older-adults, OSA is not associated with any particular pattern of cognitive-impairment at cross-section; however, OSA is associated with the development of MCI or AD with symptomatic patients who have a higher likelihood of associated disturbed sleep/cognitive-impairment driving these findings. CPAP treatment may be effective in improving cognition in OSA patients with AD. Recent trends demonstrate links between OSA and AD-biomarkers of neurodegeneration across all age-groups. These distinct patterns provide the foundation for envisioning better characterization of OSA and the need for more sensitive/novel sleep-dependent cognitive assessments to assess OSA-related cognitive-impairment.

Background Chronic psychological stress has been associated with hypertension, but few studies have examined this relationship in blacks. We examined the association between perceived stress levels assessed annually for up to 13 years and incident hypertension in the Jackson Heart Study, a community-based cohort of blacks. Methods and Results Analyses included 1829 participants without hypertension at baseline (Exam 1, 2000-2004). Incident hypertension was defined as blood pressure≥140/90 mm Hg or antihypertensive medication use at Exam 2 (2005-2008) or Exam 3 (2009-2012). Each follow-up interval at risk of hypertension was categorized as low, moderate, or high perceived stress based on the number of annual assessments between exams in which participants reported "a lot" or "extreme" stress over the previous year (low, 0 high stress ratings; moderate, 1 high stress rating; high, ≥2 high stress ratings). During follow-up (median, 7.0 years), hypertension incidence was 48.5%. Hypertension developed in 30.6% of intervals with low perceived stress, 34.6% of intervals with moderate perceived stress, and 38.2% of intervals with high perceived stress. Age-, sex-, and time-adjusted risk ratios (95% CI) associated with moderate and high perceived stress versus low perceived stress were 1.19 (1.04-1.37) and 1.37 (1.20-1.57), respectively (P trend<0.001). The association was present after adjustment for demographic, clinical, and behavioral factors and baseline stress (P trend=0.001). Conclusions In a community-based cohort of blacks, higher perceived stress over time was associated with an increased risk of developing hypertension. Evaluating stress levels over time and intervening when high perceived stress is persistent may reduce hypertension risk.

Importance/UNASSIGNED:The prevalence of hypertension and the risk for hypertension-related cardiovascular disease (CVD) are high among black adults. The population-attributable risk (PAR) accounts for both prevalence and excess risk of disease associated with a risk factor. Objective/UNASSIGNED:To examine the PAR for CVD associated with hypertension among black adults. Design, Setting, and Participants/UNASSIGNED:This prospective cohort study used data on 12 497 black participants older than 21 years without CVD at baseline who were enrolled in the Jackson Heart Study (JHS) from September 26, 2000, through March 31, 2004, and cardiovascular events were adjudicated through December 31, 2015. The Reasons for Geographic and Racial Differences in Stroke (REGARDS) study participants were enrolled from July 1, 2003, through September 12, 2007, and cardiovascular events were adjudicated through March 31, 2016. Data analysis was performed from March 26, 2018, through July 10, 2019. Exposures/UNASSIGNED:Normal blood pressure and hypertension were defined using the 2017 American College of Cardiology/American Heart Association blood pressure guideline thresholds. Main Outcomes and Measures/UNASSIGNED:The PAR for CVD associated with hypertension, calculated using multivariable-adjusted hazard ratios (HRs) for CVD, coronary heart disease, heart failure, and stroke associated with hypertension vs normal blood pressure. Prevalence of hypertension among non-Hispanic black US adults 21 years and older without CVD was calculated using data from the National Health and Nutrition Examination Survey, 2011-2014. Results/UNASSIGNED:Of 12 497 participants, 1935 had normal blood pressure (638 [33.0%] male; mean [SD] age, 53.5 [12.4] years), 929 had elevated blood pressure (382 [41.1%] male; mean [SD] age, 58.6 [11.8] years), and 9633 had hypertension (3492 [36.3%] male; mean [SD] age, 62.0 [10.3] years). For a maximum 14.3 years of follow-up, 1235 JHS and REGARDS study participants (9.9%) experienced a CVD event. The multivariable-adjusted HR associated with hypertension was 1.91 (95% CI, 1.48-2.46) for CVD, 2.41 (95% CI,1.59-3.66) for coronary heart disease, 1.52 (95% CI, 1.01-2.30) for heart failure, and 2.20 (95% CI, 1.44-3.36) for stroke. The prevalence of hypertension was 53.2% among non-Hispanic black individuals. The PAR associated with hypertension was 32.5% (95% CI, 20.5%-43.6%) for CVD, 42.7% (95% CI, 24.0%-58.4%) for coronary heart disease, 21.6% (95% CI, 0.6%-40.8%) for heart failure, and 38.9% (95% CI, 19.4%-55.6%) for stroke. The PAR was higher among those younger than 60 years (54.6% [95% CI, 37.2%-68.7%]) compared with those 60 years or older (32.0% [95% CI, 11.9%-48.1%]). No differences were present in subgroup analyses. Conclusions and Relevance/UNASSIGNED:These findings suggest that a substantial proportion of CVD cases among black individuals are associated with hypertension. Interventions to maintain normal blood pressure throughout the life course may reduce the incidence of CVD in this population.

Importance/UNASSIGNED:Black individuals and Hispanic individuals are less likely to recognize stroke and call 911 (stroke preparedness), contributing to racial/ethnic disparities in intravenous tissue plasminogen activator use. Objective/UNASSIGNED:To evaluate the effect of culturally tailored 12-minute stroke films on stroke preparedness vs the usual care practice of distributing stroke education pamphlets. Design, Setting, and Participants/UNASSIGNED:Cluster randomized clinical trial between July 26, 2013, and August 16, 2018, with randomization of 13 black and Hispanic churches located in urban neighborhoods to intervention or usual care. In total, 883 congregants were approached, 503 expressed interest, 375 completed eligibility screening, and 312 were randomized. Sixty-three individuals were ineligible (younger than 34 years and/or did not have at least 1 traditional stroke risk factor). Interventions/UNASSIGNED:Two 12-minute stroke films on stroke preparedness for black and Hispanic audiences. Main Outcomes and Measures/UNASSIGNED:The primary outcome was the Stroke Action Test (STAT), assessed at baseline, 6 months, and 12 months. Results/UNASSIGNED:In total, 261 of 312 individuals completed the study (83.7% retention rate). Most participants were female (79.1%). The mean (SD) age of participants was 58.57 (11.66) years; 51.1% (n = 159) were non-Hispanic black, 48.9% (n = 152) were Hispanic, and 31.7% (n = 99) had low levels of education. There were no significant end-point differences for the STAT at follow-up periods. The mean (SD) baseline STAT scores were 59.05% (29.12%) correct for intervention and 58.35% (28.83%) correct for usual care. At 12 months, the mean (SD) STAT scores were 64.38% (26.39%) correct for intervention and 61.58% (28.01%) correct for usual care. Adjusted by education, a post hoc subgroup analysis revealed a mean (SE) intervention effect of 1.03% (0.44%) (P = .02) increase per month in the low-education subgroup (about a 10% increase in 12 months). In the high-education subgroup, the mean (SE) intervention effect was -0.05% (0.30%) (P = .86). Regarding percentage correct, the low-education intervention subgroup improved from 52.4% (7 of 21) to 66.7% (14 of 21) compared with the other subgroups. Conclusions and Relevance/UNASSIGNED:No difference was observed in stroke preparedness at 12 months in response to culturally tailored 12-minute stroke films or conventional stroke education pamphlets. Additional studies are required to confirm findings from a post hoc subgroup analysis that suggested a significant education effect. Trial Registration/UNASSIGNED:ClinicalTrials.gov identifier: NCT01909271.

Importance/UNASSIGNED:Little is known regarding health outcomes associated with higher blood pressure (BP) levels measured outside the clinic among African American individuals. Objective/UNASSIGNED:To examine whether daytime and nighttime BP levels measured outside the clinic among African American individuals are associated with cardiovascular disease (CVD) and all-cause mortality independent of BP levels measured inside the clinic. Design, Setting, and Participants/UNASSIGNED:This prospective cohort study analyzed data from 1034 African American participants in the Jackson Heart Study who completed ambulatory BP monitoring at baseline (September 26, 2000, to March 31, 2004). Mean daytime and nighttime BPs were calculated based on measurements taken while participants were awake and asleep, respectively. Data were analyzed from July 1, 2017, to April 30, 2019. Main Outcomes and Measures/UNASSIGNED:Cardiovascular disease events, including coronary heart disease and stroke, experienced through December 31, 2014, and all-cause mortality experienced through December 31, 2016, were adjudicated. The associations of daytime BP and nighttime BP, separately, with CVD events and all-cause mortality were determined using Cox proportional hazards regression models. Results/UNASSIGNED:A total of 1034 participants (mean [SD] age, 58.9 [10.9] years; 337 [32.6%] male; and 583 [56.4%] taking antihypertensive medication) were included in the study. The mean daytime systolic BP (SBP)/diastolic BP (DBP) was 129.4/77.6 mm Hg, and the mean nighttime SBP/DBP was 121.3/68.4 mm Hg. During follow-up (median [interquartile range], 12.5 [11.1-13.6] years for CVD and 14.8 [13.7-15.6] years for all-cause mortality), 113 CVD events and 194 deaths occurred. After multivariable adjustment, including in-clinic SBP and DBP, the hazard ratios (HRs) for CVD events for each SD higher level were 1.53 (95% CI, 1.24-1.88) for daytime SBP (per 13.5 mm Hg), 1.48 (95% CI, 1.22-1.80) for nighttime SBP (per 15.5 mm Hg), 1.25 (95% CI, 1.02-1.51) for daytime DBP (per 9.3 mm Hg), and 1.30 (95% CI, 1.06-1.59) for nighttime DBP (per 9.5 mm Hg). Nighttime SBP was associated with all-cause mortality (HR per 1-SD higher level, 1.24; 95% CI, 1.06-1.45), but no association was present for daytime SBP (HR, 1.13; 95% CI, 0.97-1.33) and daytime (HR, 0.95; 95% CI, 0.81-1.10) and nighttime (HR, 1.06; 95% CI, 0.90-1.24) DBP. Conclusions and Relevance/UNASSIGNED:Among African American individuals, higher daytime and nighttime SBPs were associated with an increased risk for CVD events and all-cause mortality independent of BP levels measured in the clinic. Measurement of daytime and nighttime BP using ambulatory monitoring during a 24-hour period may help identify African American individuals who have an increased cardiovascular disease risk.

Background Left ventricular hypertrophy (LVH) is associated with an increased risk for cardiovascular disease (CVD) events and all-cause mortality. Many individuals without LVH have a left ventricular mass that exceeds the level predicted by their sex, body size, and cardiac workload, a condition called inappropriate left ventricular mass (iLVM). We investigated the association of iLVM with CVD events and all-cause mortality among blacks. Methods and Results We analyzed data from the Jackson Heart Study, a community-based cohort of blacks. The current analysis included 4424 participants without CVD and with an echocardiogram at baseline. Among this cohort, the prevalence of iLVM was 13.8%. There were 262 CVD events and 419 deaths over a median follow-up of 9.7 years (maximum, 12 years). Compared with participants without iLVM, participants with iLVM had a higher rate of CVD events and all-cause mortality. After multivariable adjustment, including for the presence of LVH, iLVM was associated with an increased risk of CVD events (hazard ratio, 1.87; 95% CI, 1.33-2.62). The multivariable-adjusted hazard ratio for all-cause mortality was 1.29 (95% CI, 0.98-1.70). Among participants without and with LVH, the multivariable-adjusted hazard ratios of iLVM for CVD events were 2.53 (95% CI, 1.68-3.81) and 1.21 (95% CI, 0.74-2.00), respectively (P_interaction=0.029); and for all-cause mortality, the hazard ratios were 1.24 (95% CI, 0.81-1.89) and 1.26 (95% CI, 0.86-1.85), respectively (P_interaction=0.664). Conclusions iLVM is associated with an increased risk for CVD events among blacks without LVH.

OBJECTIVES/OBJECTIVE:Hypertension occurs frequently among black populations around the world. In the United States (US) health system, interventions since the 1960s resulted in improvements in hypertension awareness, management and control among African Americans. This is in stark contrast to current health systems in African countries. To objectively assess the current situation in South Africa, we compared the cardiovascular health status of African Americans from 1960 to 1980 to black South Africans from recent years, as there is potential to implement best practices from the US. We also reviewed the recent cardiovascular health changes of a South African population over 10 years. METHODS:Men and women were included from three studies performed in the United States (Evans County Heart Study; Charleston Heart Study; NHANES I and II) and one in South Africa (PURE, North West Province). We compared blood pressure (BP), BMI, cholesterol, diabetes and smoking status. RESULTS:Age-adjusted SBP and DBP of South African men were lower than US studies conducted from 1960 to 1971 (Evans County; Charleston; NHANES I; all P < 0.001) but similar to NHANES II (P = 0.987) conducted in 1976. South African women had lower SBP than all four of the US studies (all P < 0.001); their DBP was lower than Evans County and Charleston studies, but similar to NHANES I and II. Reviewing South African data, BMI increased steeply over 10 years in women (P < 0.001) but not men (P = 0.451). CONCLUSION/CONCLUSIONS:Blood pressure of South Africans is lower than African Americans from the 1960s, but comparable for 1970s to 1980s. With obesity of South African women rising sharply, escalating figures for hypertension and diabetes are anticipated.

BACKGROUND:The adoption, intention, initial decision or action to implement evidence-based strategies for hypertension control in real-world settings is a challenge in low- and middle-income countries. Although stakeholders are essential for the adoption of evidence-based interventions, data on how to engage them to improve uptake of these strategies is lacking. Using a realist synthesis of stakeholder perspectives, the authors describe a process for engaging stakeholders to identify facilitators and barriers to the adoption of an evidence-based task-strengthening strategy for hypertension control in Ghana. OBJECTIVES/OBJECTIVE:To identify stakeholder perceptions of the factors influencing the adoption of evidence-based task-shifting strategies for hypertension control in Ghana. METHODS:A realist evaluation of interviews, focus groups, and brainstorming activities was conducted to evaluate stakeholder perceptions of an evidence-based strategy designed to identify, counsel, and refer patients with hypertension for care in community health centers. Stakeholders included community health officers, administrators, and policymakers from the Ghana Health Service, researchers, and community health officers in community-based health planning services in the Kintampo region of Ghana. The study used a realist synthesis approach to thematically analyze the qualitative data generated. RESULTS:Sixty-two stakeholders participated in the study. They identified inner contextual characteristics such as the provision of resources, training, supervision, and monitoring as well as community outreach as important for the adoption of an evidence-based strategy in Ghana. The findings highlight how stakeholders are faced with multiple and often competing system strains when contemplating uptake of evidence-based strategies for hypertension control. CONCLUSIONS:Through the application of a realist synthesis of stakeholder perceptions, the study identified factors likely to enhance the adoption of an evidence-based strategy for hypertension control in Ghana. The lessons learned will help shape the translation of evidence in real-world settings, and could be valuable in future planning to enhance the adoption of evidence-based strategies for hypertension control in LMICs.

BACKGROUND:Assessing the practice capacity for hypertension management and control within community-based health planning and services system is an important step toward implementing evidence-based interventions to reduce uncontrolled hypertension at the community level. OBJECTIVES/OBJECTIVE:To assess the capacity and readiness of community health workers to implement a task-strengthening strategy for hypertension control (TASSH) at the community level. METHODS:This was a cross-sectional study guided by the Consolidated Framework for Implementation Research conducted among community health workers in 6 contiguous districts within the Brong-Ahafo Region of Ghana. Study variables were described using frequency tables. RESULTS:A total of 179 community health officers (CHOs) were interviewed. The majority of respondents knew lifestyle-related messages to be provided to their clients such as heart-healthy diets (91.6%, n = 164), physical activity (90.5%, n = 162), and low sodium intake (88.3%, n = 158), but not about other lifestyle-modifying messages such as caffeine reduction (46.4%, n = 83). The majority (79%) of the respondents did not know the names of the first-line hypertension medications. Fifty-one percent of respondents did not know about the blood pressure threshold for initiation of blood pressure management. About 90% of respondents had not been trained on hypertension management. More than 80% are however motivated to implement the TASSH intervention. CONCLUSIONS:The majority of CHOs in this study were aware of lifestyle modifications such as diet modifications and increase in physical activity. However, their knowledge was limited in the blood pressure threshold for initiating treatment and in the knowledge of first-line hypertension medication, irrespective of the number of years practiced. Training on hypertension is also low. However, CHOs are motivated to control hypertension at the community level. Community-level interventions such as TASSH can leverage on their motivation to demonstrate an impact on hypertension control.