Nephrolithiasis among middle aged and elderly urban Chinese: A report from prospective cohort studies in Shanghai

Kidney stone risk factors are understudied among Asians. Our study objective was to investigate associations of obesity and other chronic diseases with incident kidney stones among the urban Chinese.

Included in this study are 2 prospective cohorts: the Shanghai Women's Health Study (N = 69,166) and Shanghai Men's Health Study (N= 58,054). Incident kidney stones were determined by self-report in 2004 and 2008. Cox regression models were used to evaluate the associations of study variables with stone risk with adjustment of demographics, medical history, and dietary intakes.

There were 2,653 incident stones over 1,007,958 person-years of follow-up. Overall incidence rates (per 1,000 person-years, 95% CI) were 2.10 (1.99-2.21) among women and 3.80 (3.59-4.02) among men. Higher BMI was associated with risk [BMI≥25 versus 18.5-24.9 kg/m2, women: HR =1.14 (95% CI 1.01-1.28); men: HR=1.17 (1.03-1.32)]. High waist-hip-ratio (≥0.80 and ≥0.90 for women and men, respectively) was associated with risk (HR 1.13, 95% CI 1.01-1.27 for women; HR 1.19, 95% CI 1.05-1.35 for men). Coronary heart disease or stroke history was associated with risk in women only (HR 1.31, 95% CI 1.10-1.56). Hypertension history was associated with risk in men only (HR 1.27, 95% CI 1.11-1.45). No significant association with diabetes mellitus was observed.

Among the Chinese, kidney stone incidence in men is almost twice that of women. Obesity is a shared risk factor. Hypertension history is associated with risk in men, while history of coronary heart disease or stroke is associated with risk in women.

Journal of endourology. 2017 Oct 19 [Epub ahead of print]

Xiang Shu, Hui Cai, Yong-Bing Xiang, Honglan Li, Loren Lipworth, Nicole L Miller, Wei Zheng, Xiao-Ou Shu, Ryan S Hsi

Vanderbilt University Medical Center, Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Nashville, Tennessee, United States ; ., Vanderbilt University Medical Center, 12328, Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Nashville, Tennessee, United States ; ., Renji Hospital, Shanghai Jiaotong University School of Medicine, SKLORG & Department of Epidemiology, Shanghai Cancer Institute, Shanghai, China ; ., Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China ; ., Vanderbilt University Medical Center, Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Nashville, Tennessee, United States ; ., Vanderbilt University School of Medicine, Dept. of Urologic Surgery , A-1302 Medical Center North , Nashville, Tennessee, United States , 37232 ; ., Vanderbilt University Medical Center, Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Nashville, Tennessee, United States ; ., Vanderbilt University Medical Center, 12328, Division of Epidemiology, Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Nashville, Tennessee, United States ; ., Vanderbilt University Medical Center, 12328, Urologic Surgery , A-1302 Medical Center North , Nashville, Tennessee, United States , 37232 ; .