乌鸦传媒

Recently, the term nonalcoholic fatty liver disease (NAFLD) was replaced with the term metabolic dysfunction-associated steatotic liver disease (MASLD) to better describe this disease and remove the possible stigma associated with the word 鈥渇atty.鈥�^1,2 Additionally, some experts have suggested that the etiologic mechanisms for alcohol-related liver disease might have some overlap with those of NAFLD.^1,2

To have MASLD, an individual needs to have steatotic liver disease plus at least 1 out of the following 5 cardiometabolic risk factors¹:

• Body mass index (BMI) > 25 kg/m2 or waist circumference > 94 cm (for males) or > 80 cm (for females) 
• Hemoglobin A1c (HbA1c) > 5.7% or a history of diabetes
• Blood pressure 鈮� 130/85 mm Hg or a history of high blood pressure
• Plasma high-density lipoprotein (HDL) levels 鈮� 40 mg/dL (males) or 鈮� 50 mg/dL (females) 
• Triglyceride level 鈮� 150 mg/dL

To investigate this topic further, Weiwen Chai, PhD, of the Department of Nutrition and Health Sciences, University of Nebraska-Lincoln, and Meng-Hua Tao, PhD, of the Department of Public Health Science, Henry Ford Health System, Detroit, used the new nomenclature and definition of MASLD in relation to the overall and sex-specific associations of serum levels of several lipid-soluble micronutrients with MASLD, including tocopherols (forms of vitamin E), retinol, vitamin D (25[OH]D), and carotenoids. Their report was published recently in the journal Nutrients.¹

What the investigators discovered

In the current study, MASLD was present in 1148 (27.7%) participants (34.1% of men and 21.2% of women).¹ The patients with MASLD were older (P < .0001) and less well-educated (P = .006). They also had a higher incidence of diabetes; higher blood pressure, BMI, waist circumference, HbA1c, and triglycerides; and lower HDL levels (P < .0001 for all). Additionally, MASLD was more prevalent in Hispanic participants (P = .002) and former smokers (P < .0001).

There was an increased likelihood of MASLD with higher serum 伪-tocopherol (Ptrend = .03) and 纬-tocopherol (Ptrend < .0001). Conversely, the odds of having MASLD were lower with higher levels of serum 25(OH)D (Ptrend = .0001), 伪-carotene (Ptrend < .0001), 脽-carotene (Ptrend < .0001), 伪-cryptoxanthin (Ptrend < .0001), 脽-cryptoxanthin (Ptrend = .008), combined lutein and zeaxanthin (Ptrend < .0001), and lycopene (Ptrend = .02). After adjustment of serum high-sensitivity C-reactive protein concentration, the results were still significant for 纬-tocopherol (Ptrend < .0001).

Most of the results were the same for men and women, other than serum 伪-tocopherol, for which the levels were associated with an increased likelihood of MASLD in men (Ptrend = .01) but not in women (Ptrend = .67).

The impacts of alcohol consumption and diet

Drs. Chai and Tao also accounted for alcohol consumption and found similar associations of serum micronutrients with MASLD. Serum 纬-tocopherol levels had a positive association with MASLD for both low and moderate alcohol consumers (Ptrend < .0001 for both). Both the low and moderate subgroups had inverse associations with 伪-carotene (Ptrend < .0001 and Ptrend = .004, respectively) and 脽-carotene (Ptrend < .0001 and Ptrend = .008, respectively). The low alcohol consumption group had inverse associations with serum 25(OH)D (Ptrend < .0004), 伪-cryptoxanthin (Ptrend < .0001), 脽-cryptoxanthin (Ptrend = .002), combined lutein and zeaxanthin (Ptrend < .0001), and lycopene (Ptrend = .002); this was not the case, however, for the moderate consumption subgroup (P > .05). Retinol had an inverse association with MASLD in the study participants with moderate alcohol intake (Ptrend = .004), but not in the low consumption subgroup (Ptrend = .20).

The authors also looked at the correlations between dietary intake and serum micronutrients, as past studies have shown that they鈥檙e not always the same. They found that the correlation was higher for the carotenoids (伪-carotene, 脽-carotene, 脽-cryptoxanthin, combined lutein and zeaxanthin, and lycopene) than for 伪-tocopherol, retinol, and vitamin D, both in the patients with and without MASLD.

Clinical implications and future research

This study is unique, Drs. Chai and Tao stated, because to their knowledge it鈥檚 the first to investigate associations between serum levels of major lipid-soluble micronutrients and newly defined MASLD in a representative sample of U.S. adults.

鈥淥ur study found that higher serum 伪-tocopherol and 纬-tocopherol levels were associated with increased odds of MASLD,鈥� the authors summarized in their report. 鈥淗igher serum 25(OH)D and carotenoid levels were associated with reduced odds of having the condition. In general, the associations of lipid-soluble micronutrients with MASLD were comparable both between men and women as well as between those with low and moderate alcohol consumption. Our results suggest potential protective associations of serum lipid-soluble micronutrients such as 25(OH)D and carotenoids with MASLD whereas the positive associations between tocopherols and MASLD may indicate potential pathophysiological conditions associated with the condition.鈥�¹

鈥淒ue to the cross-sectional nature [of our study], our results should be confirmed by future longitudinal studies,鈥� Drs. Chai and Tao concluded.¹

Published: July 08, 2024