Modifiable Lifestyle Factors for Primary Prevention of CKD: A Systematic Review and Meta-Analysis

Abstract

Background: Despite increasing incidence of CKD, no evidence-based lifestyle recommendations for CKD primary prevention apparently exist.

Methods: To evaluate the consistency of evidence associating modifiable lifestyle factors and CKD incidence, we searched MEDLINE, Embase, CINAHL, and references from eligible studies from database inception through June 2019. We included cohort studies of adults without CKD at baseline that reported lifestyle exposures (diet, physical activity, alcohol consumption, and tobacco smoking). The primary outcome was incident CKD (eGFR<60 ml/min per 1.73 m²). Secondary outcomes included other CKD surrogate measures (RRT, GFR decline, and albuminuria).

Results: We identified 104 studies of 2,755,719 participants with generally a low risk of bias. Higher dietary potassium intake associated with significantly decreased odds of CKD (odds ratio [OR], 0.78; 95% confidence interval [95% CI], 0.65 to 0.94), as did higher vegetable intake (OR, 0.79; 95% CI, 0.70 to 0.90); higher salt intake associated with significantly increased odds of CKD (OR, 1.21; 95% CI, 1.06 to 1.38). Being physically active versus sedentary associated with lower odds of CKD (OR, 0.82; 95% CI, 0.69 to 0.98). Current and former smokers had significantly increased odds of CKD compared with never smokers (OR, 1.18; 95% CI, 1.10 to 1.27). Compared with no consumption, moderate consumption of alcohol associated with reduced risk of CKD (relative risk, 0.86; 95% CI, 0.79 to 0.93). These associations were consistent, but evidence was predominantly of low to very low certainty. Results for secondary outcomes were consistent with the primary finding.

Conclusions: These findings identify modifiable lifestyle factors that consistently predict the incidence of CKD in the community and may inform both public health recommendations and clinical practice.

Keywords: alcohol; chronic kidney disease; diet; exercise; lifestyle; smoking.

Figure 1.

There was a reduced odds of CKD in people who were exposed to a higher vegetable intake and potassium intake and an increased odds of CKD in people who were exposed to a higher sodium intake. Association of (A) vegetable intake, (B) potassium intake, (C) sodium intake, and incident CKD. Note that the association estimate for each lifestyle factor is presented on the ratio (OR or RR) that was predominantly used in the included studies. IV, inverse variance.

Figure 2.

There is a significant reduced odds of incident CKD from increased levels of physical activity.

Figure 3.

There was a reduced risk of CKD in people who has a higher alcohol consumption and an increased odds of CKD in people who were exposed to higher tobacco smoking. Association of (A) alcohol consumption, (B) tobacco smoking, and incident CKD. Note that the association estimate for each lifestyle factor is presented on the ratio (OR or RR) that was predominantly used in the included studies. IV, inverse variance.

Figure 4.

The association of vegetable intake, potassium intake, physical activity, alcohol consumption, sodium intake, and tobacco smoking was consistent across incident CKD and KRT, however had varying association to GFR decline and albuminuria. NA, not applicable. ^aThe four studies of sodium intake and GFR decline were not meta-analyzable because two of the studies reported means and variance but not ratio data.