Whether single or additive, obesity is a significant risk factor for chronic liver disease, according to a study published in The American Journal of Gastroenterology. Investigators concluded that future case-finding strategies that use a risk factor approach should include obesity in the proposed algorithms.
Obesity is a major global health challenge with approximately 2.1 billion individuals worldwide were reported to be overweight in 2013. Moreover, obesity has been associated with liver fibrosis, yet guidelines do not yet indicate it as an independent risk factor with a high index of suspicion of advanced disease. This prospective study recruited participants from a primary care practice in the inner city, Leicester, England, from January 2015 to March 2016. The aim of the study was to characterize the risk of clinically signiﬁcant liver disease assessed by transient elastography (TE) within subpopulations of a community stratiﬁed by risk factors for obesity and/or type 2 diabetes (T2D) and/or hazardous alcohol use. Clinically significant liver disease was defined by an elevated reading threshold of ≥8.0 kPa.
Of the 576 participating patients, 369 had obesity, 533 had a reliable TE reading, and 66 (12.4%) had an elevated reading consistent with clinically signiﬁcant liver disease (≥8.0 kPa). Of the participants with an elevated reading and a single risk factor, 60.0% had obesity as their only risk factor. The proportion of participants with an elevated TE reading was similar among participants with obesity (8.9%) and among participants with the more recognized independent risk factors of T2D (10.8%) and hazardous alcohol use (4.8%). Risk of an elevated reading further increased when obesity was combined with other risk factors, particularly increased body mass index combined with T2D (36.7%). Furthermore, 31% of all patients with an elevated TE reading had obesity as their only risk factor. In a patient with T2D and a BMI from 30 to 34.9 kg/m2, the odds of having an elevated TE reading was nearly 5-times higher (OR, 5.24; 95% CI, 1.21-22.69; P =.027) compared with a similar patient with a BMI <25 kg/m2. This risk further increased with hazardous alcohol use.
Limitations include the use of TE as a surrogate marker for clinically significant liver disease. There has also been some debate as to whether a raised BMI in itself could be a confounding factor and falsely raise the liver stiffness measurement.
Overall, study investigators concluded, “implementation of case-ﬁnding strategies using a risk factor approach which includes obesity is feasible and oﬀers an opportunity to conduct clinical trials of screening for liver disease.”
Harris R, Card TR, Delahooke T, Aithal GP, Guha IN. Obesity is the most common risk factor for chronic liver disease: Results from a risk stratification pathway using transient elastography [published online August 27, 2019]. Am J Gastroenterol. doi: 10.14309/ajg.0000000000000357