Steatotic liver disease phenotypes in the United States: The impact of alcohol consumption assessment

Prevalence of steatotic liver disease and associated fibrosis in the United States: Results from NHANES 2017-March 2020Journal of HepatologyPreviewNon-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disorder globally, affecting approximately one-quarter of the world’s population.1 Recently, a Delphi conference conducted by multiple societies put forth a proposition to rechristen NAFLD as steatotic liver disease (SLD) and metabolic dysfunction-associated steatotic liver disease (MASLD). This endeavor seeks to better reflect the evolving understanding of the disease and ameliorate any stigma attached to it.2 The current study aims to assess the prevalence of various subtypes of SLD and the risk of fibrosis progression, comparing them with NAFLD. Full-Text PDF The Authors received no specific funding for this work. The manuscript was written by the authors without any external writing assistance. SC and GP designed the study, wrote, reviewed and edited the manuscript. SC researched and analyzed data. All authors approved the final version of the manuscript to be published. SC is the guarantor of this work. we read with interest the research letter by Luo et al., recently published in the Journal [[1]Luo N. Zhang X. Huang J. Chen H. Tang H. Prevalence of Steatotic Liver Disease and Associated Fibrosis in the United States: Results from NHANES 2017-March 2020.J Hepatol. 2023; Abstract Full Text Full Text PDF Google Scholar]. The Authors applied the recent definition and diagnostic criteria for steatotic liver disease (SLD) proposed in a multi-society Delphi consensus [[2]Rinella ME, Lazarus JV, Ratziu V, Francque SM, Sanyal AJ, Kanwal F, et al. A multi-society Delphi consensus statement on new fatty liver disease nomenclature. J Hepatol.Google Scholar] to the general US population in order to estimate the prevalence of SLD as a whole, as well as on its different phenotypes (i.e. MASLD and MetALD). To achieve this goal they analyzed data obtained in the 2017-2020 cycles of the National Health and Nutrition Examination Survey (NHANES). We recently published a manuscript with the same purpose and conducted within the same patient population [[3]Ciardullo S. Carbone M. Invernizzi P. Perseghin G. Exploring the landscape of steatotic liver disease in the general US population.Liver International. 2023; Crossref Scopus (5) Google Scholar]. Nonetheless, significant discrepancies are present between the two reports. In particular, Luo et al. (using a controlled attenuation parameter (CAP) cut-off of 285 dB/m) report a prevalence of SLD of 35.7%, with MASLD and MetALD having similar prevalence rates of 19.9% and 15.2%, respectively. In relative terms, MASLD would account for 55.7% of SLD and MetALD for 42.6%. On the other hand, our data show a much different picture, with MASLD comprising 89.4% of SLD, and MetALD contributing for only 7.7% of SLD cases. As we applied a slightly different CAP cut-off in our study (274 dB/m), to make a more direct comparison, we re-analyzed data using the 285 dB/m cut-off and reporting prevalence rates in the overall US population. All analyses were conducted using Stata version 17 (StataCorp), taking into account the complex design of NHANES. According to our calculations, while the prevalence of SLD was in line with the Authors’ estimate at 35.4% (95% CI 32.8-38.1), prevalence of MASLD (32.1%, 95% CI 29.3-35.1) and MetALD (2.5%, 95% CI 1.8-3.4) were not. For those readers that are not familiar with the NHANES database, it should be noted that there is no single variable directly reporting the average number of drinks or grams of alcohol consumed in a week by a participant within the last year. This must be calculated based on the number of drinking days in the last year and the average number of drinks consumed on drinking days. Drinks are then converted into grams of alcohol (1 drink = 14 g of alcohol) to comply with the consensus definition using a cut-off of 140 g/week for women and 210 g/week for men. Importantly, our results are in line with other recent reports from the NHANES 2017-2020 cycles. As an example, Raza et al. recently reported a prevalence of significant alcohol consumption (>14 drinks/week for men and >7 drinks/week for women, which is similar to the consensus cut-off) of 7.5% among obese individuals in the 2017-2020 dataset [[4]Raza S.A. Sokale I.O. Thrift A.P. Burden of high-risk phenotype of heavy alcohol consumption among obese US population: results from National Health and Nutrition Examination Survey, 1999–2020.The Lancet Regional Health–Americas. 2023; 23Abstract Full Text Full Text PDF Scopus (1) Google Scholar]. This aligns quite well with a prevalence of significant alcohol consumption of 7.7% among patients with SLD reported in our manuscript. Similarly, a report from the National Center for Health statistics (which used the same alcohol cut-off values) showed a prevalence of significant alcohol consumption of 5.1% in the general US population in 2018 [[5]Boersma P, Villarroel MA, Vahratian A. Heavy drinking among US adults, 2018: US Department of Health and Human Services, Centers for Disease Control and …; 2020.Google Scholar]. On the other hand, results proposed by Luo et al. report a much higher prevalence of significant alcohol consumption of 42.6%, which was never shown in the US population. It is our guess that the Authors excluded participants that never drank alcohol in the last year (ALQ121=0), as they did not answer the subsequent question (ALQ130), which reported a missing value or that they misinterpreted the meaning of some alcohol use questions within the questionnaire. In conclusion, even though estimates of alcohol consumption through self-administered questionnaires might not be accurate, MASLD seems to be much more common than MetALD in the general US population. All authors declare no conflict of interest related to this study.