Obesity as a risk factor for diseases of the digestive system

[Prevalence of gastroesophageal reflux disease in Russia: a meta-analysis of population-based studies]

AIM

To systematize data on the prevalence of gastroesophageal reflux disease (GERD) in the adult population of Russia.

MATERIALS AND METHODS

The search for studies was conducted in the electronic databases MEDLINE/PubMed, EMBASE, and RSCI (Russian Science Citation Index) from January 2000 to December 2022. The review included relevant publications in peer-reviewed periodicals in English or Russian, publications with data from cross-sectional epidemiological studies assessing the prevalence of GERD in the Russian population, studies on adult patients with GERD, and publications with detailed descriptive statistics that allow using the data in the meta-analysis.

RESULTS

The final analysis included 6 studies involving 34,192 subjects. The overall prevalence of GERD (prevalence of heartburn ± regurgitation once a week or more frequently) in the analyzed studies was 25.605% (95% confidence interval [CI] 17.913-34.147). The analysis used a random effect model, as there was significant heterogeneity between the results in both groups (I2=99.63%; p<0.0001). The overall mean age of GERD patients in the study population was 48.14 (95% CI 32.25-4.03) years. The prevalence of GERD in the male population was 23.653% (95% CI 13.351-35.832) and 25.457% (95% CI 17.094-34.849) in females.

CONCLUSION

This meta-analysis demonstrated that GERD is a common esophageal disease in the Russian population, affecting approximately one in four country residents.

Metabolically associated fatty liver disease – a disease of the 21st century: A review

Metabolically associated fatty liver disease (MAFLD) is a widespread chronic disease characterized by increased accumulation of fat in the liver, which is based on metabolic dysfunction. The incidence of MAFLD is well over 20% in most regions of the world and is on an increasing trend. Current thinking considers the etiology and pathogenesis of MAFLD under the concept of "multiple parallel blows". According to this model, the development and progression of the disease are due to the interaction of multiple genetic, environmental and adaptive factors, which include specific genetic polymorphisms (e.g., the PNPLA3 gene) and epigenetic modifications, dietary patterns (e.g. high saturated fat and fructose intake), sedentary activity, obesity, insulin resistance, dysregulation of adipokines, lipotoxicity, oxidative stress, and gut microbiota dysbiosis (small intestinal bacterial overgrowth syndrome). The basis for the diagnosis of MAFLD is the presence of proven hepatic steatosis in combination with one of the following criteria: overweight/obesity, presence of type 2 diabetes mellitus, signs of metabolic dysregulation. Nonmedicamental therapies recommended for patients with MAFLD include weight loss (if overweight or obese), reduction of saturated fatty acid and fructose intake, and inclusion of adequate amounts of omega-3 polyunsaturated fatty acids and dietary fibre (psyllium) in the diet. Pharmacotherapy of MAFLD should be aimed at correcting insulin resistance, improving liver function and reducing the risk of associated diseases.

Gastroesophageal reflux disease: risk factors, current possibilities of diagnosis and treatment optimisation

Gastroesophageal reflux disease (GERD) is one of the most common causes of health care seeking at the primary care level in many countries. At an epidemiological level, GERD has been shown to be associated with a number of risk factors: obesity, tobacco smoking, alcohol abuse, certain patterns of eating behaviour, and the use of several medications. GERD is now regarded as a heterogeneous disease and includes different phenotypes (erosive reflux disease, non-erosive reflux disease, hypersensitive oesophagus, functional heartburn), the proper diagnosis of which improves the effectiveness of therapy in patients with heartburn symptoms. Daily impedance–pH monitoring is known to be an integral part of the diagnostic algorithm for GERD and is a functional diagnostic method to record all types of refluxes entering the oesophagus regardless of pH, to assess their association with symptoms, and to determine whether patients with heartburn symptoms belong to a particular phenotype. Esophageal manometry plays a key role in the evaluation of patients with heartburn symptoms, as it helps to rule out other conditions that may mimic GERD: achalasia cardia and scleroderma esophagus. This technique is used to assess thoracic esophageal motility and sphincter function and in the assessment of patients prior to antireflux surgery or in the refractory course of GERD. The article describes in detail GERD risk factors (triggers of heartburn), as well as diagnostic aspects, taking into account a differentiated approach to patients with heartburn based on daily impedance–pH monitoring data in accordance with the current guidelines and recommendations.

Steatohepatitises: etiological variants, principles of diagnosis and management

Steatohepatitises is an etiologically heterogeneous group of pathological changes in the liver, which are characterized by the inflammatory infiltration of the hepatic parenchyma with underlying fatty degeneration of hepatocytes. Whatever is the etiological cause, the clinical significance of steatohepatitis involves the formation of liver fibrosis and, as a result, an increased risk of developing liver cirrhosis and hepatocellular carcinoma, which are life-threatening conditions. It is common practice to identify the following etiological variants of steatohepatitis: metabolic (55–65% of cases), alcoholic (45–55% of cases) and drug-induced (approximately 5% of cases). The pathogenetic basis of metabolic steatohepatitis lies in the mechanisms of increased lipolysis, excess free fatty acid pool and reduced β-oxidation stemming from obesity and insulin resistance. Pathogenetic factors mediating the development of alcoholic steatohepatitis are the toxic activity of acetaldehyde and increased CYP2E1 activity. Intake of some hepatotoxic drugs increases lipogenesis in  hepatocytes and disrupts the electron transport chain, which leads to the formation of liver steatosis followed by transformation into steatohepatitis. Whatever is the etiological varient, steatohepatitis is asymptomatic in the prevailing majority of cases. However, some patients may present complaints of weakness, discomfort, or indolent pain in the right hypochondrium. A detailed history taking is essential for the establishment of the etiological cause of liver damage. Laboratory tests allow to diagnose steatohepatitis in increased levels of hepatic transaminases, usually not exceeding 2–3 times the normal values. In addition to liver enzymes, increased levels of alkaline phosphatase and GGTP can also be observed in steatohepatitis. Ultrasound imaging is the most accessible instrumental tool in clinical practice to establish the primary diagnosis of hepatic steatosis. Indirect elastometry is an equally informative non-invasive method for diagnosing steatohepatitis, which allows to measure both the degree of steatosis (the function of determining the ultrasonic controlled attenuation parameter (CAP) and liver fibrosis.