Evidence is limited regarding the associations of non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) with the development of nephrolithiasis. This study aimed to assess the associations of NAFLD and MAFLD with the risk of incident nephrolithiasis, using data from two cohort studies conducted in China and UK.
Prospective cohort study.
26,490 participants without nephrolithiasis at baseline in the Tianjin Chronic Low-grade Systemic Inflammation and Health Cohort Study (TCLSIH) and 294,577 participants in the UK Biobank.
Fatty liver diagnosed by abdominal ultrasonography in the TCLSIH and by the hepatic steatosis index (HSI) in the UK Biobank. NAFLD and MAFLD were defined according to standard clinical criteria in both cohorts.
Nephrolithiasis was confirmed by ultrasonography in the TCLSIH and identified through ICD-10 and OPCS-4 in the UK Biobank.
Cox proportional hazards regression analysis was used to assess the relationship between exposures and incident nephrolithiasis.
The TCLSIH and the UK Biobank recorded 806 and 2,743 new cases of nephrolithiasis during a median follow-up of 4 and 12 years, respectively. Participants in both cohorts showed a significantly increased risk of nephrolithiasis in the setting of NAFLD (TCLSIH: HR=1.69, 95% CI 1.46-1.95; UK Biobank: HR=1.66, 95% CI 1.53-1.79) and MAFLD (TCLSIH: HR=1.79, 95% CI 1.55-2.08; UK Biobank: HR=1.54, 95% CI 1.42-1.66) after multivariable adjustments.
Observational nature limits causal inferences; generalizability limited outside of the cohorts studied; limited diagnostic approaches to detect nephrolithiasis; unavailability of stone composition data.
Both NAFLD and MAFLD are associated with a higher risk of nephrolithiasis. The results suggest that NAFLD/MAFLD and their associated metabolic conditions may represent modifiable risk factors for nephrolithiasis.
American journal of kidney diseases : the official journal of the National Kidney Foundation. 2025 Nov 12 [Epub ahead of print]
Song Bai, Xin Yang, Qiuju Sheng, Qing Zhang, Li Liu, Shaomei Sun, Xing Wang, Ming Zhou, Qiyu Jia, Kun Song, Kaijun Niu, Yang Ding, Yang Xia
Department of Urology Surgery, Shengjing Hospital of China Medical University, China Medical University, Shenyang, China., Department of Data Center, Shengjing Hospital of China Medical University, China Medical University, Shenyang, China; Department of Clinical Epidemiology, Shengjing Hospital of China Medical University, China Medical University, Shenyang, China., Department of Infectious Diseases, Shengjing Hospital of China Medical University, China Medical University, Shenyang, China; Diagnosis and Treatment Centre for Liver Diseases of Liaoning Province Key Laboratory for Viral Hepatitis of Liaoning Province, Shenyang, China., Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China., School of Public Health of Tianjin University of Traditional Chinese Medicine, Tianjin, China; Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China. Electronic address: ., Department of Infectious Diseases, Shengjing Hospital of China Medical University, China Medical University, Shenyang, China; Diagnosis and Treatment Centre for Liver Diseases of Liaoning Province Key Laboratory for Viral Hepatitis of Liaoning Province, Shenyang, China. Electronic address: ., Department of Data Center, Shengjing Hospital of China Medical University, China Medical University, Shenyang, China; Department of Clinical Epidemiology, Shengjing Hospital of China Medical University, China Medical University, Shenyang, China. Electronic address: .