Kidney Medicine (Dec 2023)
The Fruit and Veggies for Kidney Health Study: A Prospective Randomized Trial
Abstract
Rationale & Objective: Providing fruits and vegetables (F&Vs) to health care system patients with elevated urine albumin-creatinine ratio (ACR) reduced ACR, slowed chronic kidney disease (CKD) progression and reduced cardiovascular disease (CVD) risk factors in previous studies. This study evaluated a community-based strategy in lower-income populations to identify African Americans with elevated ACR before health care system involvement and sustain them in a 6-month F&V protocol with (F&V + Cook) and without (F&V Only) cooking instructions, with the hypothesis that adjuvant cooking instructions with F&Vs would further reduce ACR. Study Design: Prospective, randomized, parallel 2-arm design. Setting & Participants: African American adults with ACR >10 mg/g creatinine randomized to 1 of 2 study arms. Interventions: Two cups/day of F&Vs with or without cooking instructions in participants followed 6 months. Outcomes: Participants sustaining the F&V protocol and between-group indicators of CVD risk, kidney injury, and dietary intake at 6 weeks and 6 months. Results: A total of 142 African American adults (mean age, 57.0 years; ACR, 27.4 mg/g; body mass index, 34.4; 24.9% CKD 1; 24.8% CKD 2; 50.4% CKD 3; 55% female) randomized to F&V Only (n=72) or F&V + Cook (n=70), and 71% were retained at 6 months. Participants received 90% of available F&V pick-ups over 6 weeks and 69% over 6 months. In the adjusted model, 6-month ACR was 31% lower for F&V + Cook than F&V Only (P = 0.02). Net 6-week F&V intake significantly increased and biometric variables improved for participants combined into a single group. Limitations: Small sample size, low-baseline ACR, and potential nonresponse bias for 24-hour dietary recall measure. Conclusions: These data support the feasibility of identifying community-dwelling African Americans with ACR indicating elevated CVD and CKD risk and sustaining a F&V protocol shown to improve kidney outcomes and CVD risk factors and provides preliminary evidence that cooking instructions adjuvant to F&Vs are needed to lower ACR. Funding: National Institute on Diabetes, Digestive, and Kidney Diseases grant “Reducing chronic kidney disease burden in an underserved population” (R21DK113440). Trial Registration: NCT03832166. Plain-Language Summary: African Americans, particularly those in low-income communities, have increased rates of chronic kidney disease (CKD) with worsening outcomes over time. Giving fruits and vegetables to individuals with CKD identified in health care systems was previously shown to reduce kidney damage, measured by urine protein albumin, and slow kidney function decline. We recruited African Americans in low-income communities with increased urine albumin levels. They received fruits and vegetables for 6 months, and we tested whether added cooking instructions further reduced urine albumin levels. Most participants continued to receive fruits and vegetables throughout the 6 months. Those given cooking instructions had lower urine albumin levels after 6 months, indicating decreased kidney damage. Providing cooking instructions with fruits and vegetables appears to lessen kidney damage more than just fruits and vegetables alone.