Vitamin E for people with non-alcoholic fatty liver disease

Abstract

Rationale Non‐alcoholic fatty liver disease (NAFLD), recently renamed metabolic dysfunction‐associated steatotic liver disease (MASLD), is the most common liver disease worldwide, affecting an estimated 3 in 10 people. The available treatment is far from optimal. Diet and lifestyle changes to promote weight loss and weight loss maintenance are the basic management of NAFLD, but these are difficult to achieve and maintain. Vitamin E has shown beneficial effects on oxidative stress, which plays a major role in the pathogenesis of NAFLD. However, there is uncertainty about the effects of vitamin E for people with NAFLD. Objectives To evaluate the beneficial and harmful effects of vitamin E alone, or vitamin E in combination with other vitamins or minerals, versus placebo or no intervention in people with NAFLD. Search methods We used recommended Cochrane search methods. The latest search was performed on 2 February 2024. Eligibility criteria We included randomised clinical trials that compared vitamin E alone, or in combination with other vitamins or minerals, at any dose, duration, and route of administration, versus placebo or no intervention, in people with NAFLD of any age, sex, or ethnic origin. We included participants with imaging techniques or histology‐proven NAFLD and minimal alcohol intake, and participants with steatohepatitis who had liver biopsies. Outcomes Our critical outcomes were all‐cause mortality, liver‐related mortality, and serious adverse events. Our important outcomes were liver‐related morbidity, health‐related quality of life, non‐serious adverse events, biochemical response, and imaging assessment of the degree of fatty liver. Risk of bias We used Cochrane's RoB 2 tool to assess risk of bias for each of the predefined outcomes. Synthesis methods We used standard Cochrane methods. We used GRADE to assess the certainty of evidence. Included studies We included 16 randomised clinical trials involving 1066 paediatric and adult participants with NAFLD. Experimental groups received vitamin E alone (14 trials) or vitamin E in combination with vitamin C (2 trials). Control groups received placebo in 13 trials and no intervention in three trials. Daily dosages of oral vitamin E ranged from 298 international units (IU) to 1000 IU. Co‐interventions were lifestyle and low‐calorie diet interventions in 13 trials, ursodeoxycholic acid in one trial, unchanged diet and physical activity in one trial, and baseline treatments for type 2 diabetes in one trial. Nine trials had more than two intervention groups, but we used only the groups in which vitamin E alone or vitamin E in combination with vitamin C were compared with placebo or no intervention. In total, 7.9% (84/1066) of participants dropped out. Follow‐up ranged from 2 months to 24 months. Synthesis of...