Impact of habitual intake of glucosamine, fresh fruit, and tea on the risk of urolithiasis: A two-sample Mendelian randomization study.

Dietary patterns have a significant impact on the occurrence of urolithiasis. This study aimed to investigate the causal relationships between the consumption of glucosamine, fresh fruits, and tea, and the predisposition to urinary stones using a Mendelian randomization (MR) approach. Genetic proxies for these dietary factors were obtained from the UK Biobank, while the summary data for urolithiasis genome-wide association analyses were sourced from the FinnGen consortium. Five MR methodologies, namely inverse variance weighted (IVW), MR-Egger regression, weighted median, weighted mode, and simple mode, were employed in the analysis. To validate the findings, sensitivity evaluations such as the MR-PRESSO disruption test and Cochran Q test for heterogeneity were performed. The IVW method showed that glucosamine consumption had a strong inverse association with urolithiasis risk (Odds Ratio [OR] = 0.006, 95% Confidence Interval [CI] 0.0001-0.287, P = .009), surpassing the associations of fresh fruits (OR = 0.464, 95% CI 0.219-0.983, P = .045) and tea (OR = 0.550, 95% CI 0.345-0.878, P = .012). These findings were consistent when verified using alternative MR techniques, and the sensitivity analyses further supported their credibility. The results of this MR analysis demonstrate that regular consumption of glucosamine, fresh fruits, and tea is inversely correlated with the risk of developing urolithiasis.