Dietary factors and risk of kidney stone: a case-control study in southern China

Abstract

Objective: Formation of kidney stones is a multifactorial disease, and diet and lifestyle are suggested to contribute remarkably to increased prevalence. The population of Guangzhou, China has a high prevalence rate of kidney stones; however, its risk factors are still unknown. The aim of this study was to investigate the dietary risk factors for kidney stones in southern China.

Design: A case-control study was carried out.

Setting: This study was carried out at the Department of Health Management Center, Guangzhou Nanfang Hospital, China.

Subjects: This study involved 1,019 newly diagnosed kidney stone patients and 987 healthy control subjects.

Intervention: A questionnaire regarding dietary patterns and supplements was used to investigate the risk factors for kidney stone formation.

Main outcome measure: Food intake frequency, beverage and alcohol consumption, food supplements, and anthropometry were assessed.

Results: In the analysis, we found positive associations of kidney stones with consumption of grains (odds ratio [OR] = 2.08; 95% confidence interval [CI] = 1.08, 4.02) and bean products (OR = 3.50; 95% CI = 1.61, 7.59) in women. The variable "fluid drinking" showed a significant protective effect against kidney stones in men (OR = 0.57; 95% CI = 0.36, 0.88). Consuming leafy vegetables more than 3 times per day was positively associated with stones in both men and women (OR = 2.02; 95% CI = 1.04, 3.91 and OR = 3.86; 95% CI = 1.48, 10.04, respectively). Other dietary factors, dietary supplements, and specific food were not related to kidney stone formation in Guangzhou, China.

Conclusion: The results confirmed that specific diet can affect stone formation in the Chinese population, and varied risk factors were found for different genders.