Fatty liver disease: heterogeneous phenotype

Abstract

Relevance. Nonalcoholic fatty liver disease (NAFLD) holds a leading position among the causes of diffuse liver diseases, both in Russia and globally. Moreover, there is a persistent trend of increasing prevalence, especially among patients with metabolic risk factors. The Purpose of the Study: To assess the frequency of detecting fatty liver disease associated with metabolic syndromes in the Republic of Adygea and elucidate the characteristics of disease phenotypes across different age groups. Materials and methods. At stage I, 412 patients aged 18-89 years (45.4% male, 54.6% female) who visited outpatient clinics of therapeutic profile were examined. The average age of the patients was 57.0 ± 15.1 years. At stage II, the study was continued with patients diagnosed with NAFLD. Inclusion criteria for the study were: age 18 years and older, presence of fatty liver disease associated with metabolic conditions. The study continued with 191 patients diagnosed with metabolic associated fatty liver disease (MAFLD) (42.4% male, 57.6% female). The average age of the patients was 60.0 ± 12.4 years. Exclusion criteria from the study were: acute inflammatory diseases or exacerbation of chronic diseases during the study period, presence of viral hepatitis, alcoholic liver disease, autoimmune liver diseases, pregnancy, lactation, and use of medications or narcotics. The diagnosis of fatty liver disease was established in accordance with the recommendations of the Scientific Society of Gastroenterologists of Russia (2021) and the Russian Gastroenterological Association (2022). The diagnosis of metabolic-associated fatty liver disease (MAFLD) was based on visual evidence of hepatic fat accumulation (steatosis) obtained through ultrasonography, accompanied by one of the following criteria: excess body weight or obesity, type 2 diabetes mellitus, and/or signs of metabolic changes, defined as the presence of at least two of the following criteria: MS1 - waist circumference (WC) ≥102 cm in men and ≥88 cm in women; MS2 - body mass index (BMI) ≥25 kg/m²; MS3 - prediabetes (impaired fasting glycemia), homeostatic model assessment of insulin resistance (HOMA-IR) index ≥2.5; MS4 - presence of type 2 diabetes mellitus (T2DM); MS5 - blood pressure ≥130/85 mmHg or the patient receiving specific pharmacological treatment; MS6 (serum C-reactive protein >2 mg/L); MS7 - presence of dyslipidemia or the patient receiving specific pharmacological treatment. Patients were divided into age groups as follows: 18-44 years - young age (Group I); 45-59 years - middle age (Group II); 60-74 years - elderly age (Group III); 75-89 years - old age (Group IV). The study was approved by the Ethics Committee of the Federal State Budgetary Educational Institution “Maykop State Technological University, Medical Institute”. Results. The frequency of detection of fatty liver disease associated with metabolic syndromes in the Republic of Adygea, according to population screening data, was 46.4% (n=191). Out of 191 patients with ultrasound-detected evidence of steatosis, one in every fourth patient (25.1%, n=48) had deviations in liver test parameters from the reference values (laboratory signs of steatohepatitis). There were an average of 4.6±1.0 syndromes per patient in the age group 18-44 years. In the age group of 45-59 years, the average was 4.7 ± 1.1 syndromes, in the age group of 60-74 years, it was 5.0 ± 0.9, and in the age group of 75-89 years, it was 4.8 ± 1.0 syndromes, without statistical differences between the groups. In the age group of 18-44 years, the highest proportion was represented by lipid metabolism disorders (77.8%) and impaired glucose tolerance, HOMA-IR >2.5 (38.9%). In the age groups of 45-59 years and 60-74 years, the highest proportion was represented by type 2 diabetes mellitus (80.3% and 98.9%, respectively) and arterial hypertension (83.6% and 91.6%, respectively). In the age group of 75-89 years, the highest proportion was represented by type 2 diabetes mellitus (100%), elevated levels of serum C-reactive protein (58.8%) (indicating systemic inflammation), and chronic kidney disease (100%). The identified associations suggest the presence of specific age-related disease phenotypes, necessitating an appropriate volume of preventive measures and targeted therapy.