Minireviews
Copyright ©The Author(s) 2021.
World J Gastroenterol. Jun 14, 2021; 27(22): 3064-3072
Published online Jun 14, 2021. doi: 10.3748/wjg.v27.i22.3064
Table 1 Main findings regarding the association between fatty liver disease and coronavirus disease 2019 in adults
Ref.       
Study design
Population
NAFLD
Main findings
Mahamid et al[34]Retrospective case-control study, SZMC, Jerusalem71 hospitalized patients with COVID-19 infection, both genders, age ≥ 18.0 yr (mean age 51.0 ± 21.7), 22 NAFLD, 49 non-NAFLDCT within hospitalization or recently madeSignificant association between NAFLD and severity of COVID-19 even after adjustments for obesity, hypertension, metabolic syndrome, diabetes, and smoking. This association was independent of metabolic syndrome and/or its components. NAFLD patients have an increased risk of severe COVID-19 in both genders, in particular in males (Male: P = 0.001 Female: P = 0.002)
Ji et al[28]Retrospective case-control study. Patients of two COVID Hospital in China202 patients with COVID-19 (hospitalized and follow-up within 12 mo of the diagnosis). Median age 44.5 (34.8-54.1), 163 patients with stable disease (37.6% of patients with NAFLD), 39 patients with progressive disease (25.8% of patients with NAFLD)NAFLD defined as hepatic steatosis index: 8 × (ALT/AST) + BMI (+ 2 if type 2 diabetes, + 2 if female) > 36 and/or USMale patients aged > 60 yr, with higher BMI, underlying comorbidities, and NAFLD were associated with COVID-19 progression. Patients with NAFLD had higher risk of disease progression, longer viral shedding times, and higher likelihood of abnormal liver function from admission to discharge than patients without NAFLD
Zhou et al[31]Cohort study, Asian ethnicity 55 MAFLD patients with COVID-19 were 1:1 matched by age (± 5 yr), sex, and BMI (± 1 unit) to COVID-19 patients without MAFLD. Age < 60 yrCT The presence of MAFLD was associated with severity of COVID-19 even after full adjustment (age, sex, smoking status, obesity, diabetes, hypertension) and a trend to increased duration of hospitalization. MAFLD patients had higher levels of CRP, ALT, AST, GGT, fasting blood glucose, and triglycerides
Medeiros et al[27]Retrospective case-control study. Radiology Departments of Hospital Beneficiencia Portuguesa, San Paolo- Brasil316 patients clinically suspected of having COVID-19 infection: -n.204: RT-PCR positive; -n.112: RT-PCR and chest CT negative pattern. Age > 18 yrCT: Attenuation value of ≤ 40 HU, measured in the region of interest (commonly in the right hepatic lobe) in non-enhanced phaseHigher prevalence of steatosis in affected patients, even after adjustments for sex and age
Forlano et al[29]Retrospective cohort study. Imperial College Healthcare NHS Trust (London, United Kingdom)193 hospitalized, adult patients with COVID-19 infection and CT imaging, NAFLD: 61 (31%); Non-NAFLD: 132 (66%), excluded: 5 (3%)US or CT dated within 1 yr from the admission for COVID-19 or a known diagnosis of NAFLD. FIB-4 index for fibrosisNo difference in terms of admission to ICU and in mortality between NAFLD and non-NAFLD patients. NAFLD patients were significantly younger at presentation
Gao et al[30]Cohort study. Four hospitals in China130 nondiabetic patients with COVID-19: 65 MAFLD and 65 controls were 1:1 matched by age (± 5 yr) and sexCTMAFLD presence in nondiabetic patients was associated with a 4-fold increased risk of severe COVID-19, even after adjusting for age, sex, and coexisting comorbidities. The risk of severe COVID-19 increased with increasing numbers of metabolic risk factors
Targher et al[33]Retrospective cohort study. Four hospitals in China310 hospitalized, adult patients with COVID-19 infectionCT: FIB-4 index and NFS used to categorize liver fibrosis in low, intermediate, or highIn patients with MAFLD the presence of intermediate or high fibrosis (FIB-4 or NFS) was associated with a higher risk of severe COVID-19, even after adjusting for sex, obesity, and diabetes
Sharma et al[32]ReviewAdult patientsCT/FIB-4 index and NFSPatients with MAFLD had higher risk of disease progression, longer viral shedding times, higher likelihood of abnormal liver function, and 4-6-fold increased risk of severe disease than patients with no MAFLD. Younger patients (age < 60 yr) were also at greater risk for increased severity of COVID-19