CKD Outcomes Improve for Black Adults When DASH Diet Is Combined With Coaching, Assistance

Some efforts to promote healthy eating in vulnerable populations with chronic kidney disease (CKD) have included diet coaching or financial assistance. A study presented at Kidney Week 2022 examined the effect of combining both, adding diet coaching to an intervention for Black adults with hypertension and advanced CKD that also included money for groceries.

Black adults have higher rates of hypertension and advanced CKD in the United States, and potential reasons for these disparities may include a lack of access to healthy foods—such as food deserts in cities created by a lack of access to a supermarket and a lack of community investment—and knowledge gaps about healthy eating.

The Dietary Approaches to Stop Hypertension, or DASH, emphasizes a heart-healthy diet that is low in sodium and rich in potassium and other nutrients.

Diedre C. Crews, MD, ScM, FASN, deputy director, Johns Hopkins Center for Health Equity and professor of medicine, said the hypothesis of the 2-phase study was that it would lead to a 20% greater reduction in urinary albumin excretion and improvements in blood pressure. The study included 150 Black adults with urine albumin-to-creatinine ratio (ACR) ≥30 and <1000 mg/g, and estimated glomular filtration ration (eGFR) ≥30 ml/min/1.73m².

The mean age of participants was 61 years; 37% were male and 44% had diabetes. The mean systolic blood pressure was 129 mmHg and eGFR was 75 ml/min/1.73m2.

Most (64%) were taking a renin-angiotensin-aldosterone system (RAAS) blocker and 26% were food insecure.

Participants were randomized 1:1 to 2 groups. The “self-directed” group followed a DASH diet for 4 months and was provided with a weekly $30 gift card to be used towards groceries (the S-DASH group). The “dietician-directed coaching” group (C-DASH) had $30 worth of “five plus” foods delivered to their home and had weekly calls with a coach. The five plus referred to 5 servings of fruits and vegetables plus nuts and beans for a total of 17,000 milligrams of potassium each week.

In both groups, weekly food allowances stopped between months 5 and 12, but the coaching group continued to have telephone calls, although at longer intervals.

The study ran from February 2018 to August 2021; 142 of the 150 participants remained in the study after COVID-19 restrictions were put in place. Characteristics were balanced across the 2 groups, except the S-DASH group had more males (44% compared with 29% in the C-DASH group).

Crews presented 4-month outcomes, which were analyzed using mixed effects regression; the primary outcome was percent change in urine ACR.

Overall, the C-DASH group had declines in urine albumin-to-creatinine ratio (UACR) that did not differ statistically from the S-DASH group. However, in the subgroup with especially high UACR, the C-DASH group had a 73.3% decrease in UACR and the S-DASH group had a 20.5% increase.

The C-DASH group had statistically significant greater increases in potassium and fruit and vegetable consumption than the group that did not have coaching. There was also a suggestion of benefit for those with diabetes (P = .09). Hyperkalemia (>5.5 mEq/L) occurred in 1 C-DASH participant, and no S-DASH participants.

“Our next steps will be to try to expand the program to support more populations disproportionately affected by kidney disease,” said Crews.

Reference

Crews DC, Dalcin AT, Carson KA, et al. Five plus buts and beans for kidneys investigators. Dietary intervention trial for hypertensive black adults with CKD. Presented at: Kidney Week 2022; November 3-6, 2022; Orlando, Florida. Abstract FR-OR64.