Associations between dietary patterns and nephrolithiasis risk in a large Chinese cohort: is a balanced or plant-based diet better?

Abstract

Purpose: Individual food items and nutrients are associated with the development of nephrolithiasis. Few studies have investigated the association between dietary patterns, particularly plant-based diets, and this disease. We aim to explore the associations between dietary patterns and incident nephrolithiasis risk. Materials and methods: This prospective cohort study included 26 490 participants. Factor analysis was applied to dietary information to identify three a posteriori dietary patterns, and six a priori plant-based dietary patterns (overall plant-based diet index [PDI], healthful plant-based diet index [hPDI], unhealthful plant-based diet index [uPDI], vegan diet, lacto-ovo-vegetarian diet, and fish-vegetarian diet) were defined. Nephrolithiasis was diagnosed using ultrasonography. Cox proportional hazard regression models were used to assess the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident nephrolithiasis related to dietary patterns. Results: After 101 094 person-years follow-up, we documented 806 incident nephrolithiasis cases. An a posteriori balanced dietary pattern characterized by a higher intake of vegetables, eggs, grains, legumes, legume products, and meat was associated with a lower risk of nephrolithiasis (P for trend = 0.02). Compared to the reference group in the lowest quartile of the balanced pattern, participants in the highest quartile had an adjusted HR (95% CI) of 0.72 (0.53–0.96) for incident nephrolithiasis. Adherence to the uPDI increased the risk of incident nephrolithiasis (P for trend < 0.01; adjusted HR_{4th quartile vs. 1st quartile}, 1.46, 95% CI, 1.14–1.97). No significant association was found between other a posteriori or a priori dietary patterns and incident nephrolithiasis. Conclusions: Adherence to a balanced dietary pattern, but not a plant-based diet, was associated with a lower nephrolithiasis risk. Moreover, higher uPDI consumption increased incident nephrolithiasis risk.