Healthy Dietary Patterns and Incidence of CKD: A Meta-Analysis of Cohort Studies

Abstract

Background and objectives: Whether a healthy dietary pattern may prevent the incidence of developing CKD is unknown. This study evaluated the associations between dietary patterns and the incidence of CKD in adults and children.

Design, setting, participants, & measurements: This systematic review and meta-analysis identified potential studies through a systematic search of MEDLINE, Embase and references from eligible studies from database inception to February 2019. Eligible studies were prospective and retrospective cohort studies including adults and children without CKD, where the primary exposure was dietary patterns. To be eligible, studies had to report on the primary outcome, incidence of CKD (eGFR<60 ml/min per 1.73 m²). Two authors independently extracted data, assessed risk of bias and evidence certainty using the Newcastle-Ottawa scale and GRADE.

Results: Eighteen prospective cohort studies involving 630,108 adults (no children) with a mean follow-up of 10.4±7.4 years were eligible for analysis. Included studies had an overall low risk of bias. The evidence certainty was moderate for CKD incidence and low for eGFR decline (percentage drop from baseline or reduced by at least 3 ml/min per 1.73 m² per year) and incident albuminuria. Healthy dietary patterns typically encouraged higher intakes of vegetables, fruit, legumes, nuts, whole grains, fish and low-fat dairy, and lower intakes of red and processed meats, sodium, and sugar-sweetened beverages. A healthy dietary pattern was associated with a lower incidence of CKD (odds ratio [OR] 0.70 (95% confidence interval [95% CI], 0.60 to 0.82); I²=51%; eight studies), and incidence of albuminuria (OR 0.77, [95% CI, 0.59 to 0.99]; I²=37%); four studies). There appeared to be no significant association between healthy dietary patterns and eGFR decline (OR 0.70 [95% CI, 0.49 to 1.01], I²=49%; four studies).

Conclusions: A healthy dietary pattern may prevent CKD and albuminuria.

Keywords: DASH; Diet; Mediterranean; adult; albuminuria; child; chronic kidney disease; chronic renal insufficiency; diet; dietary patterns; fabaceae; fat-restricted; follow-up studies; fruit; glomerular filtration rate; human; incidence; nuts; prospective studies; retrospective studies; sodium; sugars; sweetening agents; systematic review; vegetables; whole grains.

Graphical abstract

Figure 1.

PRISMA flow diagram showing the selection of studies.

Figure 2.

Study risk of bias. Each color represents a level of risk of bias: white boxes, low risk of bias; grey boxes, unclear risk of bias; black boxes, high risk of bias. Key: Newcastle–Ottawa Scale. 1. Was there a representative and well defined sample? 2. Was the follow-up of participants sufficiently long and completed? 3. Were important prognostic factors considered and measured for? 4. Were the outcomes measured accurately? 5. Were important potential confounders accounted for? 6. Was the statistical analysis appropriate for the design of the study? AHA, American Heart Association; DASH, Dietary Approach to Stop Hypertension; DGAI, Dietary Guidelines Adherence Index.

Figure 3.

Incident CKD associated with adherence to healthy dietary patterns. DASH, Dietary Approach to Stop Hypertension; IV, inverse variance.

Figure 4.

Risk of albuminuria and eGFR decline associated with adherence to healthy dietary patterns. DASH, Dietary Approach to Stop Hypertension; DGAI, Dietary Guidelines Adherence Index.