Objective: To evaluate the associations of body mass index (BMI) and waist circumference with hospitalization risk of kidney stones in Chinese adults. Methods: This study used long-term follow-up data from China Kadoorie Biobank. After excluding participants with chronic kidney disease, cancer, and extreme BMI or waist circumference values at baseline, 502 096 participants were included in the present analysis. Cox proportional hazards regression models were used to estimate the associations of BMI and waist circumference with hospitalization risk of kidney stones. Results: During an average follow-up period of (10.7±2.2) years, 12 396 participants were hospitalized for the first time with kidney stones. Using the participants with BMI (kg/m2) of 20.5-22.4 as reference, the multivariable-adjusted HR (95%CI) for those with BMI of <18.5, 18.5-20.4, 22.5-23.9, 24.0-25.9, 26.0-27.9, 28.0-29.9, and ≥30.0 were 0.96 (0.87-1.05), 0.94 (0.88-1.00), 1.11 (1.05-1.17), 1.25 (1.18-1.32), 1.29 (1.21-1.37), 1.39 (1.28-1.50), and 1.54 (1.40-1.71), respectively. For every 1 kg/m2 increase in BMI, the HR of kidney stones hospitalization increased by 4% (HR=1.04, 95%CI: 1.04-1.05). Using the participants with waist circumference (cm) of 75.0-79.9 as reference, the multivariable-adjusted HR (95%CI) for those with waist circumference of <65.0, 65.0-69.9, 70.0-74.9, 80.0-84.9, 85.0-89.9, 90.0-94.9, and ≥95.0 were 0.82 (0.74-0.91), 0.85 (0.80-0.92), 0.95 (0.89-1.00), 1.16 (1.09-1.22), 1.22 (1.15-1.30), 1.28 (1.19-1.38), and 1.46 (1.35-1.58), respectively. For every 5 cm increase in waist circumference, the HR of kidney stones hospitalization increased by 9% (HR=1.09, 95%CI: 1.08-1.10). After mutually adjusting for BMI and waist circumference in the above models, the association between BMI and hospitalization risk of kidney stones disappeared. In contrast, the association between waist circumference and hospitalization risk of kidney stones remained unchanged. Conclusions: BMI and waist circumference were positively associated with hospitalization risk of kidney stones. The increased waist circumference was an independent risk factor for kidney stones among Chinese adults.
目的： 分析中国成年人体质指数（BMI）和腰围与肾结石住院风险的关联。 方法： 本研究利用中国慢性病前瞻性研究的长期随访数据，剔除基线自报患有慢性肾病、恶性肿瘤、BMI和腰围为极端值的研究对象，最终纳入502 096人。采用Cox比例风险回归模型分析BMI和腰围与肾结石住院风险之间的关联。 结果： 研究对象随访（10.7±2.2）年，随访期间记录肾结石导致的首次住院共12 396例。调整潜在混杂因素后，以BMI（kg/m2）20.5~22.4者为参照组，<18.5、18.5~20.4、22.5~23.9、24.0~25.9、26.0~27.9、28.0~29.9、≥30.0者的风险比（HR）（95%CI）依次为：0.96（0.87~1.05）、0.94（0.88~1.00）、1.11（1.05~1.17）、1.25（1.18~1.32）、1.29（1.21~1.37）、1.39（1.28~1.50）、1.54（1.40~1.71）；BMI每增加1 kg/m2，肾结石住院风险的HR值增加4%（HR=1.04，95%CI：1.04~1.05）。与腰围（cm）75.0~79.9者相比，<65.0、65.0~69.9、70.0~74.9、80.0~84.9、85.0~89.9、90.0~94.9、≥95.0者的HR值（95%CI）依次为：0.82（0.74~0.91）、0.85（0.80~0.92）、0.95（0.89~1.00）、1.16（1.09~1.22）、1.22（1.15~1.30）、1.28（1.19~1.38）、1.46（1.35~1.58）；腰围每增加5 cm，肾结石住院风险的HR值增加9%（HR=1.09，95%CI：1.08~1.10）。在上述模型中相互调整BMI或腰围后，BMI与肾结石住院风险的关联消失，腰围与肾结石住院风险的关联趋势不变。 结论： 中国成年人BMI和腰围与肾结石住院风险呈正向关联，腰围增加是肾结石住院风险升高的独立危险因素。.