RU2684201C1 - Screening diagnosing method for fatty liver degeneration accompanying abdominal obesity - Google Patents

Abstract

FIELD: medicine.SUBSTANCE: invention relates to medicine, namely to therapy, surgery, methods of screening diagnostics, and can be used in determining the degree of fatty liver degeneration in patients with pathological changes in liver parenchyma in non-alcoholic fatty liver disease accompanying abdominal obesity. That is ensured by measuring blood serum concentration of triglycerides, ALT levels, fasting glucose, HDL cholesterol lipoproteins. After blood sampling, waist circumference is measured to calculate hepatic steatosis – predictor SP32 by original calculation formulas for men and women. If SP32≥0.71 units, the patient is diagnosed with hepatic steatosis with more than 32 % hepatocyte involvement.EFFECT: method provides early effective and convenient diagnosis of the given pathology in a certain group of patients by predictive detection of pathological changes in liver without using liver biopsy.1 cl, 3 dwg, 1 tbl, 4 ex

Description

This invention relates to medicine and can be used to determine the degree of fatty degeneration of the liver in patients with pathological changes in the liver parenchyma in non-alcoholic fatty liver disease accompanying abdominal obesity.

Obesity is a multidisciplinary problem and is widespread in our population; according to the DIREG 2 study, it was diagnosed in 67% of cases, and the prevalence of non-alcoholic liver steatosis is 28% [Ivashkin V.T., Drapkina OM, Mayev I.V. Trukhmanov A.S., Blinov D.V., Palgova L.K., Tsukanov V.V., Ushakova T.I. The prevalence of non-alcoholic fatty liver disease in patients with outpatient practice in the Russian Federation: the results of the DIREG 2 study. RGHGK Hepatology. 2015, T. 6, p. 31-41.]. According to the epidemiological study DIREG 2, which included an examination in 2013-2015 of more than 50 thousand patients in Russian clinics, during the physical examination, 80.0% of patients with extrahepatic stigmata were not found, which confirms the scarcity and non-specificity of clinical symptoms. In 11.2% of cases, such signs of liver damage were revealed as: palmar erythema - 1.7%, "clapping" tremor - 2.3%, yellowness of sclera - 2.3%, telangiectasia - 4.9%). Hepatomegaly and / or splenomegaly with percussion and palpation was determined only in 15.7% of cases. The heterogeneous structure of the liver (55.5%) was more common according to the results of ultrasound, followed by an increase in the size of the liver (45.8%) and a heterogeneous structure of the pancreas (36.5%), while normal ultrasound parameters were detected only in 19.2 % of cases. A high proportion of liver steatosis was found in 38.6% of patients according to ultrasound.

This confirms the rule that liver pathology is accidentally diagnosed by ultrasound examination of the liver, and clinical symptoms in rare cases correlate with morphological changes in the structure of the liver. Ultrasound examination of the liver, commonly used in clinical practice to verify non-alcoholic fatty liver disease (NAFLD) [Garvey WT, Mechanick JI, Brett EM, Garber AJ, Hurley DL, Jastreboff AM, Nadolsky K., Pessah-Pollack R., Plodkowski R. Reviewers of the AACE / ACE Obesity Clinical Practice Guidelines. Endocr Pract. 2016, T. 22, 3, pp. 1-203. Clinical Practice Guidelines. EASL-EASD-EASO Clinical Practice Guidelines for the management of non-alcoholic fatty liver disease. Journal of Hepatology. 2016, T. 64, 6, pp. 1388-1402.], Has a certain diagnostic information content. This non-invasive instrumental method, based on the determination of four ultrasound features: attenuation of the echo signal, diffuse hyperechoogenicity of the liver, increased echogenicity of the liver compared with the kidneys and vague vascular pattern. The disadvantages of this method are the complex reproducibility, ambiguity in the interpretation of the obtained data, the difficulty of fixing the results to assess the dynamics of changes, as well as a decrease in the sensitivity of the method with an increase in the amount of visceral fat.

A diagnostic standard for the stages of development and activity of a NAFLD process is a puncture biopsy of the liver [Sayiner M., Koenig A., Henry L., Younossi Z.M. Epidemiology of Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis in the United States and the Rest of the World. Hepatology. 2016, T. 10, 1, pp. 63-71. Chalasani N., Younossi Z., Lavine J.E. et al. The diagnosis and management of non-alcoholic fatty liver disease: practice guideline by the American Association for the Study of Liver Diseases, American College of Gastroenterology, and the American Gastroenterological Association. Hepatology. 2012, T. 55, pp. 2005-2023. Fan J.G., Jia J.D., Li Y.M. et al. Guidelines for the diagnosis and management of nonalcoholic fatty liver disease: update 2010: J Dig Dis. 2011, T. 12, pp. 38-44.], An invasive and expensive procedure that carries a significant percentage of complications.

A liver biopsy plays several roles, including: a) confirmation of the diagnosis; B) an assessment of steatosis, the degree of necro-inflammatory activity and the severity of fibrosis; c) the exclusion of other choleretic or related diseases; d) confirmation of the diagnosis of cirrhosis.

The disadvantages of a liver biopsy are concomitant complications (the main complications occur in 0.1% -2.3% of cases, depending on the experience of the doctor and the type of needle), sampling error, variability of the result depending on the researcher and the lack of a dynamic assessment of fibrosis [Ratziu V., Charlotte F ., Heurtier A. et al. Sampling variability of liver biopsy in nonalcoholic fatty liver disease. Gastroenterology. 2005, T. 128, p. 1898-1906.]. In addition, a liver biopsy cannot be applied to all patients with NAFLD due to the high prevalence of the disease in pediatrics, as well as the need for repeated liver biopsies to evaluate the effectiveness and treatment of the disease [Polyzos S.A., Kountouras J., Zavos C. et al. Nonalcoholic fatty liver disease: multimodal treatment options for a pathogenetically multiple-hit disease. J Clin Gastroenterol. 2012, T. 46, pp. 272-284.]. For these reasons, the detection and evaluation of non-invasive indices for NAFLD, which aim to replace liver biopsy, are the focus of extensive research worldwide. Most special serum tests are available in research laboratories and only at a significant cost, so they are of little use in countries with limited resources. Specialized forms for visualizing liver tissue, including FibroScan, have limited availability and cost [WGO Global Guidelines. NAFLD / NASH (long version). 2012.]. Elastography is a study of liver tissue that is performed using the FibroScan apparatus. The principle of elastography is based on the relationship between tissue elasticity and the degree of fibrosis: the lower the elasticity (that is, the denser the liver tissue), the more pronounced fibrosis. Fibroscanning of the liver has the following disadvantages: it is impossible to assess necrotic changes in tissues, poor sensitivity in the early stages of fibrosis, distortion of the result in overweight patients with an acute inflammatory process in the liver.

Non-invasive indexes are accurate tools for selecting patients with a high degree of disease to minimize those undergoing liver biopsy. Several algorithms are proposed for assessing the state of the liver and routine use in clinical practice to identify individuals requiring in-depth diagnostic tests. The fatty liver index (FLI)> 60, calculated taking into account BMI, waist circumference, triglycerides and GGT, as proposed by Bedogni et al., Corresponds to hepatic steatosis as determined by ultrasound [Bedogni G. , Bellentani S., Miglioli L., Masutti F., Passalacqua M., Castiglione A., Tiribelli C. The Fatty Liver Index: A simple and accurate predictor of hepatic steatosis in the general population. BMC Gastroenterol. 2006, T. 6, p. 1-7.].

For screening diagnosis of pathological changes in the liver in 2007, non-invasive bioprognostic tests were approved: Steatoscrin, Fibrotest (FT) and Fibromax (FM) (Biopredictive, Paris France, patent US 6631330) [Poynard T, et al. Comp Hepatol. 2004; 3: 8].

Recommended non-invasive tests to evaluate liver steatosis are the fatty liver index (FLI), SteatoTest and NAFLD tests; all of them are validated both for the general population and for patients with obesity and reliably predict metabolic disturbances in the human body, liver damage and cardiovascular outcomes / mortality [Clinical Practice Guidelines. EASL-EASD-EASO Clinical Practice Guidelines for the management of non-alcoholic fatty liver disease. Journal of Hepatology. 2016, T. 64, 6, pp. 1388-1402.]. At the moment, these tests cannot be called publicly available for practical public health due to the high cost or inaccessibility of incoming studies and recommend them for screening applications [Crossan C, Tsochatzis E. A., Longworth L., et al. Cost-effectiveness of non-invasive methods for assessment and monitoring of liver fibrosis and cirrhosis in patients with chronic liver disease: systematic review and economic evaluation. Health Technology Assessment. 2015, T. 19, 9, pp. 1-409.]. In this case, the only non-invasive test that calibrates the degree of steatosis according to the histological scale is SteatoScreen [Poynard T., Lassailly G., Diaz E., Clement K., Canazzo R., Tordjman J., Munteanu M., et al. Performance of biomarkers FibroTest, ActiTest, SteatoTest, and NashTest in patients with severe obesity: meta analysis of individual patient data. Plos one. 2012, T. 7, 3, p. E30325.] Having a commercial calculation algorithm. Based on this, the development of criteria for the preliminary assessment of the clinical and laboratory data of obese patients to determine the need for the appointment of expensive diagnostic and laboratory studies characterizing pathological changes is an urgent task.

Thus, the development of clinical and laboratory predictors that evaluate the various manifestations of pathology in patients with obesity is still in demand. A key issue in the treatment of these patients is early diagnosis. Now all the proposed non-invasive methods (MRI, elastography, liver obesity index index (fatty liver index, FLI), SteatoTest, NAFLD test, etc.) and invasive diagnostics (liver biopsy with histological examination) are expensive and / or focused on the diagnosis of degeneration liver in the stage of fibrosis.

The basis of the invention is the task of developing a method for diagnosing severe fatty degeneration of the liver (with a lesion of more than 32% of hepatocytes) in case of abdominal obesity, which would provide predictive detection of pathological changes in the liver, could be used as a screening method for early preclinical diagnosis of liver steatosis, was quite reliable to reduce the need for a liver biopsy, and was also available for use in a wide range of individuals in clinical practice.

The solution to this problem is provided by the fact that in a method for screening diagnostics of liver fatty degeneration in abdominal obesity by determining the concentration of triglycerides of TG in blood serum, ALT levels, fasting glucose, cholesterol, high-density lipoproteins ChsLVPP, after taking venous blood and measuring the waist circumference from the patient, they calculate liver steatosis index predictor SP32- using independent variables: waist circumference according to gender, triglyceride concentration, ALT levels, lyukozy fasting HsLPVP formula for men

SP32 _male = 0.5202 + 0.0007191 × ((FROM _male (cm) -65) × (TG (mmol / L)) + 0.001195 × ALT (E / L) + 0.02706 × Fasting glucose ( mmol / l) -0.09283 × HsLPVP (mmol / l),

for women

SP32 _female = 0.5202 + 0.0007191 × ((from _female (cm) -58) × (TG (mmol / L)) + 0.001195 × ALT (E / L) + 0.02706 × Fasting glucose ( mmol / l) -0.09283 × HsLPVP (mmol / l); and if SP32≥0.71 units, then the patient determines the presence of liver steatosis with damage to more than 32% of hepatocytes.

Thus, the method of determining the indicator is indirect.

The optimal cut-off point has no gender differences, with a value> 0.71 units. has a sensitivity of 68 [95% CI 53-81]%, specificity 88 [95% CI 68-97]%, the probability of a positive result in a patient is 5.44 times higher than in a healthy patient, the probability of pathology is 92% with positive test.

The advantage of using the formula is the universality and accessibility of the parameters used, since laboratory parameters and the results of clinical examination methods (measuring the waist circumference) are routinely performed in any institution. This can be useful for patients and society in order to reduce the risk of liver biopsy, and also reduces the cost of the analysis and does not lead to possible complications from a biopsy.

The invention is illustrated in FIG. 1, which shows a regression chart, 95% confidence interval 95% prediction interval. Steatosis 32% = 0 - liver steatosis ≤32%, Steatosis 32% = 1 - liver steatosis> 32%. In FIG. 2 shows a graphical representation of the statistical data of the research results of the predictor SP32. Notes: Steatosis_32% = 0-steatosis of the liver ≤32%, Steatosis_32% = 1 - steatosis of the liver> 32%, sex = 1 - men, sex = 2 - women. In FIG. Figure 3 presents a comparison of the effectiveness of diagnostic tests by evaluating ROC curves to determine the optimal markers of the dependence of liver steatosis with lesions of more than 32% of hepatocytes on the concentration of HDLV, indices: predictor SP32, liver obesity index FLI index, visceral obesity index VAI, LAP lipid storage coefficient , HOMA-IR index, metabolic index (MI).

To confirm the effectiveness of the proposed method, a population was tested (N = 74), in which there were no clinically expressed manifestations of steatosis. The study included 74 patients with abdominal obesity aged 18 to 68 years, of which 68% were women. Body weight included in the study was 87 [95% CI 83-90] kg, BMI - 30.1 [95% CI 28.5-31.6] kg / m ² , waist circumference (OT) - 96.5 [95 % CI 94.1-98.0] cm. OT for women is 93.5 [95% CI 90.0-96.4] cm, for men 100.0 [95% CI 97.0-105.5 ] see. Diagnosis of liver steatosis was carried out using ultrasound of the liver, as well as the FibroMax and / or SteatoScreen indices (in accordance with patent RU 2403576 C2 of BioPredictive, France). Patients who recommended a liver biopsy were excluded from the study. In all groups of patients, liver steatosis, verified by laboratory and ultrasound studies, was diagnosed by chance when examining a patient for another reason. Phenotypic signs of chronic liver disease (hepatic stigmata) have not been identified. The obtained threshold level of liver steatosis was determined by analysis of the characteristic curve. Statistical analysis of the results was carried out using the statistical package Portable Statistica 8 (StatSoft, USA), MedCalc (MedCalc Software, Belgium) and Microsoft Exel (Microsoft, USA). The level of statistical significance of the study was 5% (or 0.05). The analysis of normally distributed values was carried out using parametric methods (analysis of variance, Student t-test), in other cases, nonparametric methods (Wilcoxon, Mann-Whitney criteria) were used. A comparative analysis of qualitative variables was performed using the χ ² criterion and the exact two-sided Fisher criterion. Absolute numbers and percentages, median values (Me) and 95% confidence interval (95 CI%), and p values are presented for description. The relationship of the studied traits was evaluated using the Spearman rank correlation method.

The scattergram of the scatter and the linear regression results between the SteatoTest steatosis assessment included in the FibroMax complex and the ultrasound data for the total patient sample by comparing the ROC curves and the predictor SP32 are shown in FIG. one.

A graphical representation of these parameters in the form of a statistical summary of the distribution of results by pathology and gender: median, quartile, range and extreme values, is shown in figure 2.

The predictor SP32 has significant differences between the control and the study group: 0.65 [95% CI 0.61-0.69] units. vs 0.75 [95% CI 0.72-0.79] units, p <0.0001 (Mann-Whitney test). No significant gender differences were found: for men, the median values were 0.75 [95% CI 0.69-0.87] units, for women 0.72 [95% CI 0.70-0.74] units, p = 0.12 (Mann-Whitney test).

The predictive power of this marker, estimated by calculating the area under the ROC curve (AUC), shows high rates: AUCcn32 = 0.835 [95% CI 0.730-0.911] (for men, AUC _SP32 = 0.884 [95% CI 0.688-0.977], for women - AUC _SP32 = 0.819 [95% CI 0.685-0.914]). Given our data, the predictor SP32 has the best informational characteristics compared to other indirect methods for assessing severe liver steatosis (Table 1, Fig. 3)

Note: The p-value (Area = 0.5) <0.0001. 1- DeLong et al., 1988, 2- Binomial exact

Clinical example:

Patient G., 55 years old.

Weight, kg - 130

Height, cm - 167

Waist circumference, cm - 123

Triglycerides, mmol / L - 2.8

ALT, E / L - 28.0

Glucose, mmol / l - 6.5

HsLPVP, mmol / l - 0.9

Ultrasound of the liver: the thickness of the right lobe is 100 mm, the thickness of the left lobe is 75 mm, the signal attenuation is not detected.

Steatotest result, units - 0.92, interpretation: S3 - severe steatosis: 33% -100% of hepatocytes with steatosis.

SP32 predictor value, units - 0.78, the patient determines the presence of liver steatosis with damage to more than 32% of hepatocytes.

Patient Sh., 55 years old.

Weight, kg - 86

Height, cm - 179

Waist circumference, cm - 97

Triglycerides, mmol / L - 11.01

ALT, E / L - 75.0

Glucose, mmol / L - 5.3

HsLPVP, mmol / l - 0.8

Ultrasound of the liver: thickness of the right lobe - 126 mm, thickness of the left lobe - 88 mm, signal attenuation - detected.

Steatotest result, units - 0.92, interpretation: S3-expressed steatosis: 33% -100% of hepatocytes with steatosis.

SP32 predictor value, units - 0.93, the patient determines the presence of liver steatosis with damage to more than 32% of hepatocytes.

Patient D., 37 years old.

Weight, kg - 76

Height, cm - 160

Waist circumference, cm - 90

Triglycerides, mmol / L - 2.1

ALT, E / L - 17.0

Glucose, mmol / L - 5.1

HsLPVP, mmol / l - 1.3

Ultrasound of the liver: thickness of the right lobe - 174 mm, thickness of the left lobe - 86 mm, signal attenuation - detected.

Steatotest result, units - 0.45, interpretation: S1 - minimal steatosis: less than 5% of hepatocytes with steatosis;

SP32 predictor value, units - 0.61, the patient has no liver steatosis with damage to more than 32% of hepatocytes.

Patient K., 66 years old.

Weight, kg - 92

Height, cm - 185

Waist circumference, cm - 98

Triglycerides, mmol / L - 1.07

ALT, E / L - 18.0

Glucose, mmol / l - 5.5

HsLPVP, mmol / l - 1,6

Ultrasound of the liver: thickness of the right lobe - 134 mm, thickness of the left lobe - 67 mm, signal attenuation - detected.

Steatotest result, units - 0.32, interpretation: S0-S1: no steatosis (less than 1% of hepatocytes with steatosis).

SP32 predictor value, units - 0.57, the patient does not have liver steatosis with damage to more than 32% of hepatocytes.

The method is simple, suitable for screening, convenient for the doctor and patient. The diagnostic method according to the invention can be automated, can be advantageously used for patients with liver steatosis, including disease, to reduce the indications for liver biopsy.

Reducing the overdiagnosis of liver pathology and the corresponding reduction in the cost of an expensive examination (elastography, MRI, puncture biopsy of the liver with histological examination), as well as timely treatment and lifestyle modification according to the identified early preclinical signs of a developing pathology, as a whole within the healthcare system, will lead to a significant saving material resources. Since the measurement of used indicators in the blood is relatively inexpensive and fairly regularly performed tests in a clinical setting, the results presented can be of great importance in the aspect of public health. The identification of positive results of the predictor SP32, indicating fatty liver, should be an indication for an in-depth clinical, laboratory and instrumental examination of the patient, including the programs of the clinical examination of the population.

Claims (6)

A method for screening diagnostics of fatty liver degeneration in abdominal obesity by determining the concentration of triglycerides of TG in serum, the levels of ALT, fasting glucose, cholesterol high-density lipoproteins ChsLDPV, characterized in that after collecting venous blood and measuring the waist circumference of the patient, liver steatosis is calculated - SP32 predictor using independent variables: waist circumference according to gender, triglyceride concentration, ALT levels, fasting glucose, HsLPVP according to the formulas : for men SP32 _husband. = 0.5202 + 0.0007191 × ((FROM _husband (cm) -65) × (TG (mmol / L)) + 0.001195 × ALT (E / L) + 0.02706 × Fasting glucose (mmol / L ) -0.09283 × HsLPVP (mmol / l); for women SP32 _wives. = 0.5202 + 0.0007191 × ((FROM _wives (cm) -58) × (TG (mmol / L)) + 0.001195 × ALT (E / L) + 0.02706 × Fasting glucose (mmol / L ) -0.09283 × HsLPVP (mmol / l); and if SP32≥0.71 units, then the patient determines the presence of liver steatosis with damage to more than 32% of hepatocytes.

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