Project description:BackgroundWe aimed to investigate the associations of glycemic markers (hemoglobin A1C [HbA1C], fasting plasma glucose [FPG] and glycemic status [normoglycemia, prediabetes and diabetes]) with incident heart failure (HF) and its subtypes, among Blacks.MethodsWe included 2,290 community-dwelling Blacks (64% women, mean age 58 years) without prevalent HF from the Jackson Heart Study who attended the second exam (2005 - 2008). The associations between glycemic markers and incident HF (and subtypes including HF with preserved ejection fraction [HFpEF] and reduced ejection fraction [HFrEF]) were evaluated using Cox proportional hazards regression models, adjusting for risk factors and coronary heart disease.ResultsThere were 119 incident HF events (48 HFpEF, 58 HFrEF, and 13 unclassified HF events) over a median follow-up of 10.5 years. Higher levels of HbA1C (HR per SD increment, 1.30; 95% CI 1.12, 1.51) and FPG (HR per SD increment FPG: 1.32; 95% CI: 1.17, 1.48) were associated with a higher risk of incident HF. Compared to normal glycemia, diabetes status was associated with a higher risk of incident HF (HR: 1.24; 95%CI: 1.02, 2.05). HbA1C was significantly associated with higher risks of HFpEF (HR per SD increment: 1.41, 95% CI: 1.18, 1.69) and HFrEF (HR per SD increment: 1.32; 95% CI: 1.12, 1.56). FPG was significantly associated with higher risk of HFpEF (HR per SD increment: 1.35, 95% CI: 1.14, 1.62) but not HFrEF (HR per SD increment: 1.12; 95% CI: 0.53, 2.35).ConclusionsAmong community-dwelling Blacks, higher levels of glycemic markers were associated with higher risk of HF subtypes.
Project description:BackgroundAlthough new approaches for data collection, such as mobile technology and teleresearch, have demonstrated new opportunities for the conduct of more timely and less costly surveys in community-based studies, literature on the feasibility of conducing cardiovascular disease research using mobile health (mHealth) platforms among middle-aged and older African Americans has been limited.ObjectiveThe purpose of this study was to contribute to the knowledge regarding the penetrance of internet and mobile technologies, such as cellphones or smartphones in existing large cohort studies of cardiovascular disease.MethodsA digital connectedness survey was conducted in the Jackson Heart Study (JHS), a Mississippi-based African American cohort study, as part of the annual follow-up calls with participants from July 2017 to February 2019.ResultsOf the 4024 participants contacted, 2564 (63.7%) completed the survey. Among survey respondents, 2262 (88.2%) reported use of internet or cellphone, and 1593 (62.1%) had a smartphone. Compared to nonusers (n=302), internet or cellphone users (n=2262) were younger (mean age 80.1, SD 8.0 vs 68.2, SD 11.3 years), more likely to be affluent (n=778, 40.1% vs n=39, 15.4%), and had greater than high school education (n=1636, 72.5% vs n=85, 28.1%). Internet or cellphone users were less likely to have cardiovascular disease history compared to nonusers (136/2262, 6.6% vs 41/302, 15.8%). The prevalence of current smoking and average BMI were similar between internet or cellphone users and nonusers. Among internet or cellphone users, 1316 (58.3%) reported use of email, 504 (22.3%) reported use of apps to track or manage health, and 1269 (56.1%) expressed interest in using JHS-developed apps.ConclusionsOur findings suggest that it is feasible to use mHealth technologies to collect survey data among African Americans already enrolled in a longitudinal study. Our findings also highlight the need for more efforts to reduce the age and education divide in access and use of internet and smartphones for tracking health and research in African American communities.
Project description:BACKGROUND:Cigarette smoking has been linked with several factors associated with cardiac dysfunction. We hypothesized that cigarette smoking is associated with left ventricular (LV) structure and function, and incident heart failure (HF) hospitalization. METHODS:We investigated 4129 (never smoker n=2884, current smoker n=503, and former smoker n=742) black participants (mean age, 54 years; 63% women) without a history of HF or coronary heart disease at baseline in the Jackson Heart Study. We examined the relationships between cigarette smoking and LV structure and function by using cardiac magnetic resonance imaging among 1092 participants, cigarette smoking and brain natriuretic peptide levels among 3325 participants, and incident HF hospitalization among 3633 participants with complete data. RESULTS:After adjustment for confounding factors, current smoking was associated with higher mean LV mass index and lower mean LV circumferential strain (P<0.05, for both) in comparison with never smoking. Smoking status, intensity, and burden were associated with higher mean brain natriuretic peptide levels (all P<0.05). Over 8.0 years (7.7-8.0) median follow-up, there were 147 incident HF hospitalizations. After adjustment for traditional risk factors and incident coronary heart disease, current smoking (hazard ratio, 2.82; 95% confidence interval, 1.71-4.64), smoking intensity among current smokers (≥20 cigarettes/d: hazard ratio, 3.48; 95% confidence interval, 1.65-7.32), and smoking burden among ever smokers (≥15 pack-years: hazard ratio, 2.06; 95% confidence interval, 1.29-3.3) were significantly associated with incident HF hospitalization in comparison with never smoking. CONCLUSIONS:In blacks, cigarette smoking is an important risk factor for LV hypertrophy, systolic dysfunction, and incident HF hospitalization even after adjusting for effects on coronary heart disease.
Project description:Recent advances in geographic information systems software and multilevel methodology provide opportunities for more extensive characterization of "at-risk" populations in epidemiologic studies. The authors used age-restricted, geocoded data from the all-African-American Jackson Heart Study (JHS), 2000-2004, to demonstrate a novel use of the Lorenz curve and Gini coefficient to determine the representativeness of the JHS cohort to the African-American population in a geographic setting. The authors also used a spatial binomial model to assess the geographic variability in participant recruitment across the Jackson, Mississippi, Metropolitan Statistical Area. The overall Gini coefficient, an equality measure that ranges from 0 (perfect equality) to 1 (perfect inequality), was 0.37 (95% confidence interval (CI): 0.30, 0.45), indicating moderate representation. The population of sampled women (Gini coefficient = 0.34, 95% CI: 0.30, 0.39) tended to be more representative of the underlying population than did the population of sampled men (Gini coefficient = 0.49, 95% CI: 0.35, 0.61). Representative recruitment of JHS participants was observed in predominantly African-American and mixed-race census tracts and in the center of the study area, the area nearest the examination clinic. This is of critical importance as the authors continue to explore novel approaches to investigate the geographic variation in disease etiology.