Exercising in the COVID-19 era: implications in non-alcoholic fatty liver disease (NAFLD)

Long-term antibody response after the third dose of inactivated SARS-CoV-2 vaccine in MASLD patients

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) patients are at an elevated risk of developing severe coronavirus disease 2019 (COVID-19). The objective of this study was to assess antibody responses and safety profiles six months after the third dose of the inactivated acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine in MASLD patients.

METHODS

This study included MASLD patients and healthy volunteers without a history of SARS-CoV-2 infection. Blood samples were collected six months after receiving the third dose of the inactivated vaccine to measure the levels of neutralizing antibodies (NAbs) and anti-spike IgG antibodies against SARS-CoV-2.

RESULTS

A total of 335 participants (214 MASLD patients and 121 healthy volunteers) were enrolled. The seroprevalence of NAb was 61.7% (132 of 214) in MASLD patients and 74.4% (90 of 121) in healthy volunteers, which was a significant difference (p = 0.018). Statistically significant differences in IgG seroprevalence were also observed between MASLD patients and healthy volunteers (p = 0.004). Multivariate analysis demonstrated that the severity of MASLD (OR, 2.97; 95% CI, 1.32-6.68; p = 0.009) and age (OR, 1.03; 95% CI, 1.01-1.06; p = 0.004) were independent risk factors for NAb negativity in MASLD patients. Moderate/severe MASLD patients had a lower NAb seroprevalence than mild MASLD patients (45.0% vs. 65.5%, p = 0.016).

CONCLUSION

Lower antibody responses were observed in MASLD patients six months after their third dose of the inactivated vaccine than in healthy volunteers, providing further assistance in monitoring patients who are more vulnerable to hypo-responsiveness to SARS-CoV-2 vaccines.

COVID-19 and MAFLD/NAFLD: An updated review

The COVID-19 pandemic is ongoing and places a substantial burden on healthcare systems worldwide. As we further shed light on different disease characteristics, we identify more and more groups of people at higher risk of poor COVID-19 outcomes. Metabolic-associated fatty liver disease (MAFLD) (previously non-alcoholic fatty liver disease or NAFLD) is a common metabolic disorder characterized by fat accumulation and liver fibrosis. Given its close correlation with metabolic syndrome, an established risk factor for severe COVID-19, it is necessary to investigate its interplay with the novel coronavirus. In this study, we review the available data on COVID-19 prognosis, treatment and prevention options in patients with MAFLD, and the effect that the disease and the pandemic have on MAFLD care. Furthermore, we point out the gaps in the current literature to accentuate the work that needs to be done to improve MAFLD care during the pandemic and beyond.

Impact of Physical Activity on COVID-19

INTRODUCTION

The coronavirus disease 2019 (COVID-19) pandemic, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is seriously endangering human health worldwide. This study finds effective intervention modalities of physical activity on COVID-19 through a narrative review.

METHODS

In this study, 41 papers were selected for a narrative literature review after a comprehensive database search from 20 December 2019, to 30 August 2022.

RESULTS

41 articles meet the established criteria, and in this review, we comprehensively describe recent studies on exercise and COVID-19, including the impact and recommendations of exercise on COVID-19 prevention, patients with COVID-19, and noninfected populations.

CONCLUSIONS

The literature suggests that physical activity (PA) contributes to the prevention and treatment of COVID-19, can promote recovery of physical function, alleviate post-acute COVID-19 syndrome, and improve patients' psychological well-being. It is recommended to develop appropriate exercise prescriptions for different populations under the guidance of a physician.

Impact of COVID-19 Lockdown on Non-Alcoholic Fatty Liver Disease and Insulin Resistance in Adults: A before and after Pandemic Lockdown Longitudinal Study

Background: Non-alcoholic fatty liver disease is a chronic disease caused by the accumulation of fat in the liver related to overweight and obesity, insulin resistance, hyperglycemia, and high levels of triglycerides and leads to an increased cardiovascular risk. It is considered a global pandemic, coinciding with the pandemic in 2020 caused by the “coronavirus disease 2019” (COVID-19). Due to COVID-19, the population was placed under lockdown. The aim of our study was to evaluate how these unhealthy lifestyle modifications influenced the appearance of metabolic alterations and the increase in non-alcoholic fatty liver disease. Methods: A prospective study was carried out on 6236 workers in a Spanish population between March 2019 and March 2021. Results: Differences in the mean values of anthropometric and clinical parameters before and after lockdown were revealed. There was a statistically significant worsening in non-alcoholic fatty liver disease (NAFLD) and in the insulin resistance scales, with increased body weight, BMI, cholesterol levels with higher LDL levels, and glucose and a reduction in HDL levels. Conclusions: Lockdown caused a worsening of cardiovascular risk factors due to an increase in liver fat estimation scales and an increased risk of presenting with NAFLD and changes in insulin resistance.

Differential Effects of Dietary versus Exercise Intervention on Intrahepatic MAIT Cells and Histological Features of NAFLD

Background: Mucosal-associated invariant T (MAIT) cells promote inflammation in obesity and are implicated in the progression of non-alcoholic fatty liver disease (NAFLD). However, as the intrahepatic MAIT cell response to lifestyle intervention in NAFLD has not been investigated, this work aimed to examine circulating and intrahepatic MAIT cell populations in patients with NAFLD, after either 12 weeks of dietary intervention (DI) or aerobic exercise intervention (EI). Methods: Multicolour flow cytometry was used to immunophenotype circulating and intrahepatic MAIT cells and measure MAIT cell expression (median fluorescence intensity, MFI) of the activation marker CD69 and apoptotic marker CD95. Liver histology, clinical parameters, and MAIT cell populations were assessed at baseline (T0) and following completion (T1) of DI or EI. Results: Forty-five patients completed the study. DI participants showed decreased median (interquartile range) expression of the activation marker CD69 on circulating MAIT cells (T0: 104 (134) versus T1 27 (114) MFI; p = 0.0353) and improvements in histological steatosis grade post-intervention. EI participants showed increased expression of the apoptotic marker CD95, both in circulating (T0: 1549 (888) versus T1: 2563 (1371) MFI; p = 0.0043) and intrahepatic MAIT cells (T0: 2724 (862) versus T1: 3117 (1622) MFI; p = 0.0269). Moreover, the percentage of intrahepatic MAIT cells significantly decreased after EI (T0: 11.1 (14.4) versus T1: 5.3 (9.3)%; p = 0.0029), in conjunction with significant improvements in fibrosis stage and hepatocyte ballooning. Conclusions: These data demonstrate independent benefits from dietary and exercise intervention and suggest a role for intrahepatic MAIT cells in the observed histological improvements in NAFLD.

Prevalence of frailty in patients with non-cirrhotic non-alcoholic fatty liver disease

OBJECTIVE

End-stage chronic liver disease is associated with accelerated ageing and increased frailty. Frailty measures have provided clinical utility in identifying patients at increased risk of poor health outcomes, including those awaiting liver transplantation. However, there is limited data on the prevalence and severity of frailty in patients with non-cirrhotic non-alcoholic fatty liver disease (NAFLD). The aim of this study was to evaluate the prevalence of frailty and prefrailty in patients with non-cirrhotic NAFLD and correlate with severity of liver disease.

DESIGN

A cross-sectional analysis of functional and laboratory frailty assessments, including the Fried frailty index (FFI), a self-reported frailty index (SRFI) and a lab-based frailty index (FI-LAB), was performed in a cohort of 109 patients with NAFLD, and results compared with fibrosis staging based on transient elastography.

RESULTS

Patients with NAFLD had a high prevalence of prefrailty and frailty, with a median SRFI score of 0.18 (IQR: 0.18), FFI of 1 (IQR: 1) and FI-LAB of 0.18 (IQR: 0.12). Using the SRFI, 45% of F0/F1 patients were classified as prefrail and 20% were classified as frail, while in F2/F3 patients this increased to 36% and 41%, respectively. SRFI, 30 s sit-to-stand and FI-LAB scores increased with increasing liver fibrosis stages (p=0.001, 0.006 and <0.001, respectively). On multivariate linear regression, female gender was identified as a significant predictor of elevated frailty scores.

CONCLUSION

This study identifies a high prevalence of frailty in individuals with non-cirrhotic NAFLD. Addressing frailty through early rehabilitation interventions may reduce overall morbidity and mortality in this population.