Suboptimal sleep and incident cardiovascular disease among African Americans in the Jackson Heart Study (JHS).

BACKGROUND: Suboptimal sleep, including insufficient/long sleep duration and poor sleep quality, is a risk factor for cardiovascular disease (CVD) common but there is little information among African Americans, a group with a disproportionate CVD burden. The current study examined the association between suboptimal sleep and incident CVD among African Americans. METHODS: This study included 4,522 African Americans without CVD at baseline (2000-2004) of the Jackson Heart Study (JHS). Self-reported sleep duration was defined as very short (<6 h/night), short (6 h/night), recommended (7-8 h/night), and long (≥9 h/night). Participants' self-reported sleep quality was defined as "high" and "low" quality. Suboptimal sleep was defined by low quality sleep and/or insufficient/long sleep duration. Incident CVD was a composite of incident coronary heart disease and stroke. Associations between suboptimal sleep and incident CVD were examined using Cox proportional hazards models over 15 follow-up years with adjustment for predictors of CVD risk and obstructive sleep apnea. RESULTS: Sample mean age was 54 years (SD = 13), 64% female and 66% reported suboptimal sleep. Suboptimal sleep was not associated with incident CVD after covariate adjustment [HR(95% CI) = 1.18(0.97-1.46)]. Long [HR(95%CI) = 1.32(1.02-1.70)] and very short [HR(95% CI) = 1.56(1.06-2.30)] sleep duration were associated with incident CVD relative to recommended sleep duration. Low quality sleep was not associated with incident CVD (p = 0.413). CONCLUSIONS: Long and very short self-reported sleep duration but not self-reported sleep quality were associated with increased hazard of incident CVD.

Psychosocial correlates of apparent treatment-resistant hypertension in the Jackson Heart Study.

This corrects the article DOI: 10.1038/jhh.2016.100.

Psychosocial correlates of apparent treatment-resistant hypertension in the Jackson Heart Study.

Apparent treatment-resistant hypertension (aTRH) is associated with adverse cardiovascular outcomes. aTRH is common and disproportionately affects African Americans. The objective of this study is to explore psychosocial correlates of aTRH in a population-based cohort of African Americans with hypertension. The sample included 1392 participants in the Jackson Heart Study with treated hypertension who reported being adherent to their antihypertensive medications. aTRH was defined as uncontrolled clinic BP (⩾140/90 mm Hg) with ⩾3 classes of antihypertensive medication or treatment with ⩾4 classes of antihypertensive medication, including a diuretic. Self-reported medication adherence was defined as taking all prescribed antihypertensive medication in the 24 h before the study visit. The association of psychosocial factors (chronic stress, depressive symptoms, perceived social support and social network) with aTRH was evaluated using Poisson regression with progressive adjustment for demographic, clinical and behavioural factors. The prevalence of aTRH was 15.1% (n=210). Participants with aTRH had lower social network scores (that is, fewer sources of regular social contact) compared with participants without aTRH (P<0.01). No other psychosocial factors differed between groups. Social network was also the only psychosocial factor that was associated with aTRH prevalence in regression analyses. In age-, sex-adjusted and fully adjusted models, one additional unique source of social contact was associated with a 19% (PR=0.81; 95% confidence interval (CI): 0.68-0.94, P=0.001) and a 13% (PR=0.87; 95% CI 0.74-1.0, P=0.041) lower prevalence of aTRH, respectively. Social network was independently associated with aTRH and warrants further investigation as a potentially modifiable determinant of aTRH in African Americans.

Effectiveness of riparian buffers in controlling ground-water discharge of nitrate to streams in selected hydrogeologic settings of the North Carolina Coastal Plain.

Water-quality and hydrologic information were collected along ground-water flow paths from two well-drained and two poorly drained Coastal Plain settings in North Carolina to evaluate the relative effectiveness of riparian buffers in reducing discharge of nitrate to streams. At one well-drained site with a 100 m buffer, little or no effect was detected on surface-water quality by discharging ground water because extensive woody vegetation in the buffer was able to take up not only most nitrate, but also most ground water before discharging to the stream during the growing season (March-October). At the second well-drained site, ground water discharging to the stream from the side with a buffer contained about 2 mg/L of nitrate-nitrogen after passing through the bed of the stream compared to 6 mg/L in ground water discharging from the side with no buffer. In the poorly drained settings, nitrate in ground water decreased from about 6 mg/L in the recharge area to less than 0.02 mg/L downgradient from the riparian buffer. Ground water discharging from the side with no buffer contained 0.83 mg/L. Riparian buffers appear effective in reducing nitrate in ground water discharging to Coastal Plain streams.