Non-alcoholic fatty liver and chronic kidney disease: Retrospect, introspect, and prospect

Table 1 Incidence and prevalence of chronic kidney disease in patients with varying degrees of non-alcoholic fatty liver disease severity

Ref.	Year	n	NAFLD diagnostic modalities	Conclusion(s)
Musso et al[12]. A meta-analysis of 33 studies	2014	63902	Liver biopsy, abdominal ultrasound, elevated liver enzymes	(1) 20 cross-sectional studies: Nearly two-fold increased risk of CKD in patients with NAFLD (OR 2.12, 95%CI 1.69-2.66); (2) 11 longitudinal studies: 1.8-fold increased risk of CKD in patients with NAFLD (HR 1.79, 95%CI 1.65–1.95); and (3) advanced fibrosis associated with increased prevalence (OR 5.20, 95%CI 3.14-8.61) and incidence (HR 3.29, 95%CI 2.30-4.71) of CKD in patients with NAFLD
Mantovani et al[13]. A meta-analysis of 9 studies	2018	96595	Abdominal ultrasound; FLI; serum GGT	Incidence of CKD: (1) 1.4-fold increased long-term risk (HR 1.37, 95%CI 1.20–1.53) in patients with NAFLD with a median follow-up period of 5.2 years; and (2) 1.5-fold increased risk (HR 1.50, 95%CI 1.25-1.74) in patients with severe NAFLD (defined as NFS ≥ -1.455 or serum GGT ≥ 109 U/L)
Park et al[14]. Retrospective Cohort with Propensity Score Matching (1:3)	2019	262619	ICD-9	Incidence of CKD: 1.4-fold increased risk (aHR 1.41; 95%CI, 1.36-1.46) in patients with NAFLD after adjusting for demographics, baseline covariates, and ACEi/ARB use; Risk of incident CKD increases as the severity of NAFLD increases: (1) compensated cirrhosis (aHR, 1.47; 95%CI 1.36-1.59); and (2) decompensated cirrhosis (aHR, 2.28; 95%CI 2.12-2.46)

NAFLD: Non-alcoholic fatty liver disease; CKD: Chronic kidney disease; HR: Hazard ratio; FLI: Fatty liver index; GGT: Gamma glutamyl transferase; NFS: NAFLD fibrosis score; CI: Confidence interval; OR: Odds ratio; ACEi: Angiotensin-converting enzyme inhibitor; ARB: Angiotensin receptor blocker; ICD-9: International classification of disease-9.