Kidney Week

Abstract: SA-OR050

The DASH Diet and Blood Pressure among Black Americans with and without CKD: The Jackson Heart Study

Session Information

• Hypertension and CVD: Epidemiology and Outcomes
  October 27, 2018 | Location: 6F, San Diego Convention Center
  Abstract Time: 04:54 PM - 05:06 PM

Category: Hypertension and CVD

• 1401 Hypertension and CVD: Epidemiology, Risk Factors, and Prevention

Authors

• Tyson, Crystal C., Duke University Medical Center, Durham, North Carolina, United States

Crystal C. Tyson, MD



Dr. Crystal Tyson is a board-certified nephrologist and an ASH-certified hypertension specialist who has a clinical interest in treating difficult to control and resistant hypertension. Her research focuses on developing lifestyle strategies (i.e., diet, exercise, weight loss) to eliminate racial disparities in cardiovascular mortality among CKD populations.

• Davenport, Clemontina A., Duke University Medical Center, Durham, North Carolina, United States

Clemontina A. Davenport,

• Lin, Pao-Hwa, Duke University Medical Center, Durham, North Carolina, United States

Pao-Hwa Lin,

• Scialla, Julia J., Duke University Medical Center, Durham, North Carolina, United States

Julia J. Scialla,

• Hall, Rasheeda K., Duke University Medical Center, Durham, North Carolina, United States

Rasheeda K. Hall,

• Diamantidis, Clarissa Jonas, Duke University Medical Center, Durham, North Carolina, United States

Clarissa Jonas Diamantidis,

• Lunyera, Joseph, Duke University Medical Center, Durham, North Carolina, United States

Joseph Lunyera,

• Bhavsar, Nrupen Anjan, Duke University Medical Center, Durham, North Carolina, United States

Nrupen Anjan Bhavsar,

• Rebholz, Casey, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States

Casey Rebholz,

• Pendergast, Jane F., Duke University Medical Center, Durham, North Carolina, United States

Jane F. Pendergast,

• Boulware, L. Ebony, Duke University Medical Center, Durham, North Carolina, United States

L. Ebony Boulware,

• Svetkey, Laura P., Duke University Medical Center, Durham, North Carolina, United States

Laura P. Svetkey,

Background

Hypertension control rates are low among Black Americans, particularly among Blacks with CKD. CKD raises blood pressure (BP) through complex mechanisms. Therefore, therapies may have a different effect on BP for those with and without CKD. The DASH diet lowers BP in adults without CKD but its effect in CKD is not clear. Our preliminary data showed that markers of kidney dysfunction are associated with better BP response to the DASH diet. We tested the hypothesis that greater DASH diet accordance has a stronger association with lower BP among Blacks with CKD compared to those without CKD.

Methods

This cohort study of Jackson Heart Study participants involved 3135 Black adults enrolled between 2000 and 2004 (Exam 1) with data on office BP and habitual diet from food frequency questionnaires. We examined the cross-sectional relation of a modified-DASH diet score (excluding sodium intake; range 0-8) to SBP and DBP using linear models adjusting for demographic, behavioral, and clinical factors. We tested for interaction between the DASH score and CKD status (defined as eGFR <60 ml/min/1.73 m² and/or urine albumin-to-creatinine ratio ≥30 mg/g).

Results

Mean age was 55 years, 60% had hypertension, and 19% had CKD. Overall, the median DASH score was 1.0 (interquartile range [IQR]: 0.5-2.0), which was similar among participants with and without CKD (1.0 [IQR: 0.5-2] and 1.0 [IQR: 0.5-1.5], respectively). Among those without CKD, the DASH score was not associated with SBP (-0.4 [95% confidence interval: -1.0, 0.1] mmHg) or DBP (-0.1 [-0.4, 0.2] mmHg). Among those with CKD, a higher DASH score by one point was associated with lower SBP (-1.6 [-2.6, -0.5] mmHg) and DBP (-0.9 [-1.5, -0.3] mmHg; Figure).

Conclusion

CKD status modified the relation of the DASH score to SBP and DBP. Despite poor diet quality overall, greater DASH diet accordance was more strongly associated with lower BP among Blacks with CKD compared to those without CKD.

Funding

• Other NIH Support