For patients with nonalcoholic fatty liver disease (NAFLD), formal weight loss programs lead to statistically and clinically significant improvements in biomarkers of liver disease, based on a recent meta-analysis.
The findings support changing NAFLD guidelines to recommend weight loss interventions, according to lead author Dimitrios A. Koutoukidis, PhD, of the University of Oxford, UK, and colleagues. “Clinical guidelines around the world recommend physicians offer advice on lifestyle modification, which mostly includes weight loss through hypoenergetic diets and increased physical activity,” the investigators wrote in JAMA Internal Medicine. “However, whether clinicians provide advice and the type of advice they give vary greatly, and guidelines rarely specifically recommend treatment programs to support weight loss,” they added.
To investigate associations between methods of weight loss and improvements in NAFLD, the investigators screened for studies involving behavioral weight loss programs, pharmacotherapy, or bariatric surgery, alone or in combination. To limit confounding, studies combining weight loss with other potential treatments, such as medications, were excluded. Weight loss interventions were compared to liver disease outcomes associated with lower-intensity weight loss intervention or none or minimal weight loss support, using at least 1 reported biomarker of liver disease. The literature search returned 22 eligible studies involving 2,588 patients.
The investigators found that more intensive weight loss programs were associated with greater weight loss than lower intensity methods (-3.61 kg; I2 = 95%). Multiple biomarkers of liver disease showed significant improvements in association with formal weight loss programs, including histologically or radiologically measured liver steatosis (standardized mean difference: -1.48; I2 = 94%), histologic NAFLD activity score (-0.92; I2= 95%), presence of nonalcoholic steatohepatitis (OR, 0.14; I2 =0%), alanine aminotransferase (-9.81 U/L; I2= 97%), aspartate transaminase (-4.84 U/L; I2 = 96%), alkaline phosphatase (-5.53 U/L; I2 = 96%), and gamma-glutamyl transferase (-4.35 U/L; I2 = 92%). Weight loss interventions were not significantly associated with histologic liver fibrosis or inflammation, the investigators noted.
“The advantages [of weight loss interventions] seem to be greater in people who are overweight and with NAFLD, but our exploratory results suggest that weight loss interventions might still be beneficial in the minority of people with healthy weight and NAFLD,” the investigators wrote. “Clinicians may use these findings to counsel people with NAFLD on the expected clinically significant improvements in liver biomarkers after weight loss and direct the patients toward valuable interventions.”
“The accumulated evidence supports changing the clinical guidelines and routine practice to recommend formal weight loss programs to treat people with NAFLD,” the investigators concluded.
The study was funded by the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre and the Oxford NIHR Collaboration and Leadership in Applied Health Research. The investigators reported grants for other research from Cambridge Weight Plan.
SOURCE: Koutoukidis et al. JAMA Int Med. 2019 Jul 1. doi: 10.1001/jamainternmed.2019.2248.