Too much medicine: overdiagnosis and overtreatment of non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is now the most common cause of liver disease. This remarkable rise in prevalence over the past 20 years is largely through the recognition of fatty liver in the absence of excessive alcohol consumption as a disease. The natural history of NAFLD is incompletely understood, and although a small proportion of individuals with NAFLD will develop complications of liver disease, most will not. This raises the prospect of widespread overdiagnosis of NAFLD. Clinical practice guidelines from the European specialist societies representing hepatology, endocrinology, and obesity endorse screening for NAFLD in at-risk groups, and this further increases the likelihood of overdiagnosis and consequent overtreatment through false-positive testing. Predictable outcomes of overdiagnosis include physical harms through investigation and treatment, and psychosocial harms through disease labelling. Prospective studies are required to better understand both the benefits and risks associated with an early diagnosis of NAFLD.