Ren Zhewen, Bosma Hans, Wesselius Anke, Eussen Simone J P M, Kooi M Eline, van der Kallen Carla J H, Koster Annemarie, van Greevenbroek Marleen M J, Dagnelie Pieter, Stehouwer Coen D A, Brouwers Martijn C G J
Department of Internal Medicine, Maastricht University Medical Center, Maastricht, The Netherlands.
CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands.
JHEP Rep. 2023 Jul 18;5(11):100855. doi: 10.1016/j.jhepr.2023.100855. eCollection 2023 Nov.
BACKGROUND & AIMS: Recent studies have unveiled an association between socioeconomic position (SEP) and intrahepatic lipid (IHL) content. The aim of this study was to examine to what extent traditional lifestyle factors mediate the relationship between SEP and IHL content, independent of aetiology, and non-alcoholic fatty liver disease (NAFLD).
We used cross-sectional data derived from The Maastricht Study (N = 4,001; mean age: 60 years, 49% women, 32% low education level, 21% diabetes, 21% NAFLD). Education, income, and occupation were used as indicators of SEP. Physical activity (accelerometer), intake of total energy, alcohol, saturated fat, protein, vitamin E, dietary fibre, and fructose from sugar-sweetened beverages (SSBs) and fruit juice (food frequency questionnaires) were potential mediators. IHL content was quantified by magnetic resonance imaging. Age, sex, and type 2 diabetes were covariates. Multiple parallel mediation analyses (bootstraps = 10,000) were performed.
Individuals with a low education level had a 1.056-fold higher IHL content (95% CI: 1.03-1.08) and a 44% greater NAFLD risk (OR:1.44; 95% CI:1.18-1.77) compared with those with higher education levels. Approximately 8.9% of educational disparity in risk of IHL content was attributable to moderate-to-vigorous physical activity; 6.3% to fructose intake from SSBs; 5.5% to dietary fibre; and -23% to alcohol. Approximately 8.7% of educational disparity in risk of NAFLD was attributable to moderate-to-vigorous physical activity; and 7.7% to fructose intake from SSBs. However, the indirect effect of these mediators was small (0.998 for IHL content and 1.045 for NAFLD) in comparison to the total effect. Similar results were found when income and occupation were used as SEP indicators.
Societal measures may alleviate the burden of NAFLD and further studies that identify mediators other than traditional lifestyle factors are warranted to define the relationship underlying SEP and IHL content.
Individuals with a low or medium level of education, income, or occupational status had more fat accumulation in their livers than individuals with a higher education, income, or occupational status. This difference may be attributed to the influence of unhealthy lifestyle factors, such as reduced physical activity and a higher intake of sugar-sweetened beverages among individuals with lower socioeconomic position. Nevertheless, other yet unknown factors may also play a role.
近期研究揭示了社会经济地位（SEP）与肝内脂质（IHL）含量之间的关联。本研究旨在探讨传统生活方式因素在多大程度上介导了SEP与IHL含量之间的关系，且独立于病因及非酒精性脂肪性肝病（NAFLD）。
我们使用了来自马斯特里赫特研究的横断面数据（N = 4001；平均年龄：60岁，49%为女性，32%为低教育水平，21%患有糖尿病，21%患有NAFLD）。教育程度、收入和职业被用作SEP的指标。身体活动（加速度计）、总能量摄入、酒精、饱和脂肪、蛋白质、维生素E、膳食纤维以及来自含糖饮料（SSB）和果汁的果糖摄入量（食物频率问卷）为潜在中介因素。IHL含量通过磁共振成像进行量化。年龄、性别和2型糖尿病为协变量。进行了多项平行中介分析（自抽样 = 10000）。
与高教育水平者相比，低教育水平者的IHL含量高1.056倍（95%可信区间：1.03 - 1.08），患NAFLD的风险高44%（比值比：1.44；95%可信区间：1.18 - 1.77）。IHL含量风险中约8.9%的教育差异可归因于中度至剧烈身体活动；6.3%归因于来自SSB的果糖摄入；5.5%归因于膳食纤维；以及 - 23%归因于酒精。NAFLD风险中约8.7%的教育差异可归因于中度至剧烈身体活动；7.7%归因于来自SSB的果糖摄入。然而，与总效应相比，这些中介因素的间接效应较小（IHL含量为0.998，NAFLD为1.045）。当将收入和职业用作SEP指标时，发现了类似结果。
社会措施可能减轻NAFLD的负担，有必要开展进一步研究以确定除传统生活方式因素之外的中介因素，从而明确SEP与IHL含量之间的潜在关系。
教育水平、收入或职业地位较低或中等的个体肝脏中的脂肪堆积比教育水平、收入或职业地位较高的个体更多。这种差异可能归因于不健康生活方式因素的影响，比如社会经济地位较低的个体身体活动减少以及含糖饮料摄入量较高。然而，其他未知因素可能也起作用。
