Effect of lean status on the mortality of patients with non-alcoholic fatty liver disease (NAFLD): A systematic review and meta-analysis

Ping Miao; Zhongyi Shao; Ji Jiang

doi:10.12669/pjms.41.6.12044

Ping Miao Affiliated People’s Hospital of Ningbo University
Zhongyi Shao
Ji Jiang

DOI: https://doi.org/10.12669/pjms.41.6.12044

Keywords: NAFLD, non-alcoholic fatty liver disease, body mass index, lean, overweight, obese, all-cause mortality, systematic review, meta-analysis

Abstract

Objective: To investigate the impact of lean status as per body mass index (BMI) on mortality in cases of non-alcoholic fatty liver disease (NAFLD).

Methods: A systematic search was conducted in PubMed, Embase, and Scopus to identify relevant studies published from the inception of each database up to July 31, 2024. Observational studies that reported data on the mortality outcomes of NAFLD patients with different BMI, and provided adjusted estimates were included. The Newcastle-Ottawa Scale (NOS) was used for quality assessment. Pooled effect sizes were reported as hazard ratio (HR) with 95% confidence intervals (CI).

Results: Fourteen studies were included, of which majority were retrospective cohort studies (n=10). Objective assessment method for NAFLD i.e., imaging and/or biopsy was used in 10 studies. Compared to NAFLD patients with high BMI, lean patients had higher risk of all-cause mortality (HR 1.34, 95% CI: 1.23, 1.47), with no publication bias for any of the outcomes. Lean status correlated with elevated risk of liver disease-related mortality (HR 2.14, 95% CI: 1.18, 3.87) but had similar risk of cardiovascular (HR 0.92, 95% CI: 0.65, 1.30) and cancer-related mortality (HR 1.20, 95% CI: 0.90, 1.60).

Conclusion: Lean status of NAFLD patients correlates with higher risk of all-cause and liver disease-related mortality compared to patients with high BMI. There is a need for tailored interventions and further research to understand specific mortality risks in this subgroup of patients.

Registration No.: (PROSPERO CRD42024512065).

doi: https://doi.org/10.12669/pjms.41.6.12044

How to cite this: Miao P, Shao Z, Jiang J. Effect of lean status on the mortality of patients with non-alcoholic fatty liver disease (NAFLD): A systematic review and meta-analysis. Pak J Med Sci. 2025;41(6):1845-1853. doi: https://doi.org/10.12669/pjms.41.6.12044

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