Dietary factors and the risk of urolithiasis: A Mendelian randomization study

Abstract

Abstract Background Observational studies have indicated that dietary factors are correlated with the risk of developing urolithiasis. However, the potential factors contributing to this association remain unclear. Therefore, we adopted the Mendelian randomization (MR) analysis for assessing the causal relationship of dietary factors with the risk of developing urolithiasis. Methods A two-sample MR analysis (univariable MR and multivariable MR) was performed to study the association of several dietary factors (processed meat, beef, pork, poultry, lamb, non-oily fish, oily fish, tea, fresh fruit, dried fruit, raw vegetables, cooked vegetables, cheese, cereal, as well as alcoholic drinks) with the risk of developing urolithiasis. The exposure data were acquired from the UK biobank and published genome-wide association studies (GWAS), and the obtained outcome data were from the FinnGen database. For the purpose of assessing the causal association, we adopted inverse-variance weighted (IVW), MR-Egger, and weighted median methods. Results The MR analysis demonstrated that several genetically predicted dietary factors, including fresh fruit intake the odds ratio (OR) = 0.507; 95% confidence interval [CI] = < 0.258, 0.995>; p = 0.048), and tea intake (OR = 0.561; 95% CI = < 0.351, 0.898>; p = 0.016) decreased the risk of urolithiasis. Multivariable MR revealed fresh fruits and tea intake affected the risk of developing urolithiasis to varying degrees after adjusting the excretion of citrate, urate, calcium, and phosphate. Conclusion Our findings offer the first genetic evidence of the causality of genetically predicted fresh fruits and tea intake with the risk of developing urolithiasis. Our results suggest that tea and fresh fruit consumption can be used as preventive measures for urolithiasis.