Nghiên cứu đặc điểm một số yếu tố nguy cơ tim mạch và nồng độ asymmetric dimethylarginine huyết tương ở bệnh nhân ghép thận ttta

AND TRAININGVIET NAM MILIRATY MEDICAL UNIVERSITY NGUYEN THI THUY STUDY ON SEVERAL FEATURES OF CARDIOVASCULAR RISK FACTORS AND PLASMA ASYMMETRIC DIMETHYLARGININE CONCENTRATIONS IN KIDNEY

AND TRAINING

VIET NAM MILIRATY MEDICAL UNIVERSITY

NGUYEN THI THUY

STUDY ON SEVERAL FEATURES OF

CARDIOVASCULAR RISK FACTORS AND PLASMA ASYMMETRIC DIMETHYLARGININE CONCENTRATIONS IN KIDNEY TRANSPLANT

Viet Nam Military Medical University

Trường Đại học Y Dược Hải Phòng

Judge Ư3: PGS.TS Nguyễn Oanh Oanh

2 Viet Nam Military Medical University library

3 Central Medical Information Library

1. Nguyen Thi Thuy, Le Viet Thang (2022) Asymmetricdimethylarginine serum levels are associated with patientcharacteristics after renal transplant Tạp chí Y dược học Quân

sự, Vol 47, N05 – 2022: 180-189

2. Nguyễn Thị Thúy, Lê Việt Thắng (2022) Liên quan nồng độasymmetric dimethylarginine huyết tương với một số yếu tốnguy cơ tim mạch ở bệnh nhân bệnh thận mạn giai đoạn cuốitrước ghép thận, Tạp chí Y dược lâm sàng 108, Tập 17- Số5/2022: 153-158

3. Evaluating several clinical and subclinical characteristics ofpatients pre- and post- kidney transplant at 103 military hospital.Tập 17 số Tiếng Anh 12/2022:112-117

End-stage renal disease (ESRD) is an increasing global healthproblem and burden on the health sector in many countries,especially in low-resource countries In 2017, 9.1% (697.6 millionpeople) of the global population had ESRD, with roughly one-third(132.3 million people) from China and India (115 milion people).Individuals with ESRD have a higher chance of dying, primarilyfrom cardiovascular disease According to recent studies, patientswith ESRD are 10-100 times more likely than the general population

to die from cardiovascular disease Diabetes, hypertension,dyslipidemia, being overweight or obese, anemia, inflammation, andadvanced age were all identified as independent predictors ofcardiovascular disease in ESRD patients

Among the therapies for ESRD, kidney transplantation is the bestoption since patients may live a near-normal life, although pre-transplant cardiovascular complications continue, and it is also themajor cause of mortality in patients following kidney transplantation.Cardiovascular risk factors existed in the patient before totransplantation and were influenced by immunosuppressivemedication usage CRP, homocysteine, and asymmetricdimethylarginine (ADMA) have recently been linked tocardiovascular events in renal transplant patients

According to the previous studies, the plasma ADMAconcentrations in CKD patients was 1.13-1.36 times greater than innormal healthy persons and increased to the greatest level in theERSD stage ADMA inhibits the formation of nitric oxide (NO).This substance's content is inversely related to glomerular filtrationrate and has been linked to cardiovascular events in individuals bothbefore and after kidney transplantation High ADMA levels havebeen associated with cardiovascular events and increased mortalityrisk in ESRD patients both before and after renal transplantation As

a result, ADMA may be a predictor of cardiovascular events inpatients with post-renal disaese

Unfortunately, there are relatively few studies in Vietnam onADMA and cardiovascular disease in kidney transplant patients, and

no study on the relationship between cardiovascular risk factors andADMA Hence, we conducted the study “Study on several features

of cardiac risk factors and plasma asymmetric dimethylarginine concentrations in kidney transplant patients”

1 The objectives

1.1 Survey of several cardiovascular risk factors, atherogenic indices, plasma asymmetric dimethylarginine concentrations, and their association to clinical and subclinical outcomes in persons with end-stage chronic renal disease prior to kidney transplantation.

1.2 Assessment of changes in several cardiovascular risk factors, atherosclerotic indices and plasma asymmetric dimethylarginine levels in patients 6 months after kidney transplantation

2 New contributions of the thesis

- This is the first study on the novel cardiovascular risk factorAsymmetric dimethylarginine (ADMA) in kidney transplantpatients in Vietnam The study's findings first reveal an uniquepredictor of cardiovascular events in individuals with renal failure

- The study's findings revealed that the ADMA index in patients afterkidney transplant decreased significantly when compared to thetime before kidney transplant, implying that after the patientreceived kidney replacement surgery, it may help reduce the risk ofkidney failure-related cardiovascular events

- The enzyme immunoassay was employed in the study to evaluatepatients' plasma ADMA levels This approach is less expensivethan previous procedures, has higher accuracy, and is simple toapply, thus it may be used on all patients

- The findings of this study will be used as a foundation for futureresearch on ADMA in chronic renal disease and kidney transplantpatients to better understand the function of ADMA incardiovascular disease in these individuals

3 The layout of the thesis

The thesis consists of 139 pages, with 4 chapters: Rationale 02 pages,Chapter 1 - Introduction: 38 pages, Chapter 2 - Subjects and methods

23 pages, Chapter 3 - Results 33 pages, Chapter 4 - Discussion 40pages, Conclusion and recommendations 03 pages

The thesis has 41 tables, 11 chart 05 figures, 01 diagram, 169references including 13 Vietnamese documents and 156 Englishdocuments

CHAPTER 1 OVERVIEW

1.1 End stage chronic kidney disease

According to the NKF-KDOQI (Kiney Disease OutcomesQuality Initiative) of the American Society of Nephrology - 2012,kidney disease is considered chronic when one of the following twocriteria is met:

- Renal damage in renal structure and function, with or withoutdecreased glomerular filtration rate (GFR) > 3 months

- Decreased GFR < 60 ml/min/1.73 m2 continuously for morethan 3 months, with or without associated structural renal damage.Chronic kidney disease (CKD) is divided into five stages based

on the decline in glomerular filtration rate: stage 1 (GFR ≥ 90ml/min/1.73 m2), stage 2 (60-89 ml) /min/1.73 m2), stage 3a (45-59ml/min/1.73 m2), stage 3b (30-44 ml/min/1.73 m2), stage 4 (15-29ml/min/1.73 m2), stage 5 (<15 ml/min/1.73 m2)

1.2 Cardiovascular risk factors in chronic kidney disease patients

- Traditional risk factors include hypertension, diabetes, and diabetes, smoking, age, overweight/obesity, dyslipidemia, sex,physical activity, and left ventricular cardiac hypertrophy

pre Nonpre traditional risk factors include reduced GFR, proteinuria,anemia, calcium-phosphate imbalances, and secondaryhyperparathyroidism, chronic inflammation, oxidative stress,endothelial dysfunction, homocysteine in the blood, adinopecitn, andfibroblast growth factor

1.3 Cardiovascular complications and treatment of patients with end-stage chronic kidney disease

- Cardiovascular complications: coronary artery disease, heartfailure, heart valve disease, pulmonary hypertension, andarrhythmias

- Treatment: three forms of renal replacement therapy are available:extracorporeal dialysis, peritoneal dialysis, and kidneytransplantation

1.4 Kidney transplantation and post-transplant treatment

• Kidney transplantation: the procedure of transplanting a healthykidney from a donor to a recipient A kidney transplant can beacquired from a live or brain-dead donor After kidneytransplantation, the main clinical concern is rejection As a result,immunosuppressive medication is initiated immediately followingkidney transplantation to lower the risk of transplant rejection and toextend the life of the donated kidney

- Indication for kidney transplantation: glomerular filtration rate of

15 ml/min/1.73m2, good general condition, and pelvic vascularstatus

- Contraindications: cancer, uncontrolled infections, cardiovasculardisease, blood problems

• Post-transplant treatment: to reduce the likelihood of transplantrejection, post-transplant patients are given immunosuppressivemedicines at each step According to the stage of clinical usage, thesemedications are grouped into three groups: induction therapy(basiliximab, thymoglobulin, alemtuzumab ), maintenance therapy(cyclosporine A, prograf, mycophenolate mofetil ), and treatmentfor rejection (rituximab, bortezomib, eculizumab )

1.5 Role of ADMA in CKD patients

ADMA is a protein molecule with the chemical formula

C8H18N4O6, a molecular weight of around 202.25 kDa, and isproduced when arginine in a protein molecule is methylated by theenzyme arginine methyltransferase ADMA functions as a NOproduction inhibitor, impairing endothelial function and promotingatherosclerosis ADMA elevation has been found to be a majorpredictor of cardiovascular events and death

1.6 ADMA variation in chronic kidney disease patients

ADMA levels tend to rise shortly after renal function declinesand peak toward the end of chronic kidney disease High ADMAconcentrations in CKD patients are linked to a high level of proteinbinding, resulting in reduced ADMA clearance efficiency and renalimpairment

1.7 ADMA variation in kidney transplant patients

ADMA levels reduced dramatically in the first month aftertransplantation but remained higher than in healthy people;moreover, the decrease in ADMA levels was caused by enhanced

NO production and better endothelial function Patients'commencement of immunosuppressive medication after kidneytransplantation appears to have minimal influence on endothelialfunction improvement

1.8 The role of ADMA in cardiovascular disease

ADMA induces endothelial dysfunction, increased systemicvascular resistance, arterial blood pressure, and reduced cardiacoutput Due of the biological effects of ADMA and the much higheramounts reported in individuals with renal impairment, theassociation between ADMA and cardiovascular problems has beenstudied in high-risk patients Increased ADMA levels were shown to

be directly and independently linked with the occurrence ofcardiovascular events in patients with renal failure who had coronaryartery disease, peripheral arterial occlusion, type 1, 2 diabetes, andheart failure As a result of chronic heart disease and pulmonaryhypertension, ADMA may directly contribute to vascular damage

1.9 Method for determining ADMA concentration

Many techniques for measuring ADMA in plasma and urine arenow available, including high performance liquid chromatography(HPLC) with fluorescence detection, capillary electrophoresis, liquidchromatography combined with mass spectrometry (LC-MS), andenzyme-linked immunosorbent assay (ELISA)

Currently, commercial kits are used to quantify ADMA using theELISA approach, which is simple to use and can perform the test on

a large number of samples with a wide range This method's basis isbased on the particular matching of anti-ADMA antibody with

substrate-degrading enzyme coupled to ADMA molecule; when theantigen-antibody pairing reaction happens, the degrading enzymeactive agent and coloring agent are activated The colorconcentration increases in direct proportion to the ADMA content.Cross-reactivity of antibodies to L-arginine and other endogenous L-arginine derivatives is very low (0.02%), while the variability inADMA concentrations is observed to be relatively narrow (4, 5 -7.5%), implying a very low error The ADMA concentration rangeassessed by an ELISA kit may encompass all pathophysiologicalvalues (0.05 µmol/L - 2 µmol/L) The ADMA concentration levelsobtained from the ELISA test correspond well with the patient's realprognostic data

CHAPTER 2 SUBJECTS AND METHODS 2.1 Subjects

There were 192 participants in total, 112 (disease group) werekidney transplant patients with post-transplant follow-up, and 80(control group) were normal healthy people

2.2 Criteria for selecting subjects

- Control group: >18-year-old normal healthy adults with no medicalhistory, who are not pregnant, do not smoke, do not consumealcohol, and have accepted to participate in the study

- Patient group: ESRD patients who got a kidney transplant atMilitary Medical Hospital 103, had a comprehensive clinicalexamination and laboratory findings in accordance with researchguidelines, were properly monitored after transplantation, andconsented to participate in the study

2.3 Exclusion criteria

- Disease group: malignancy, acute infection, pregnancy or renalfailure, diabetes mellitus, systemic lupus erythematosus

2.4 Location of the study

Screening patients and medical records, blood tests,ultrasonography, and ADMA measurement were all done in MilitaryHospital 103

2.5 Methods

2.5.1 Study design: prospective, descriptive, controlled longitudinal

follow-up without intervention

2.5.2 Sample size

Sample size for objective 1:

Calculate the sample size according to the formula:

(Z1-α/2)2 x p (1-p)

n = -

D2

Where: Z = 1.96, with a confidence level of 95%

p = 0.45 (value of previous study)

D = 0.1, desired precision

Using the above calculation to establish the minimal sample size forthe study, 96 patients' plasma ADMA levels must be measured, with

n = 112 kidney transplant patients at time T0 in this investigation

Sample size for objective 2:

There were 112 patients selected at time T0, however, due to somereasons such as geographical distance, rejection andCytomegalovirus infection, the actual number of patients was stillfully monitored at 6 months After transplantation at MilitaryHospital 103 there were 75 patients who were eligible to be included

in the study

2.5.3 Content and procedures

2.5.3.1 Survey of several cardiovascular risk factors, atherogenicindices, plasma asymmetric dimethylarginine concentrations, andtheir association to clinical and subclinical outcomes in persons withend-stage chronic renal disease prior to kidney transplantation

+ Cardiovascular risk factors:

- Hypertension: when systolic BP ≥90 mmHg and/or diastolic BP

≥90 mmHg [98]

- Diabetes

- Smoking: the patient has been and is a smoker

- Dyslipidemia: the patient has a disorder in at least one of the fourlipid components

- Overweight, obese: patients with BMI ≥ 23

- Anemia

- Increased uric acid in the blood

- Increased blood CRP > 2.0 mg/L.

- Atherogenic index AIP > 0.11 CRI- I > 4.0; CRI –II >3.0; AC >2.0

+ Atheroma index

- The AIP index is divided into 3 levels:

+ AIP 0.11: low risk of cardiovascular disease

+ 0.11 < AIP ≤ 0.21: mean risk of cardiovascular disease

+ AIP > 0.21: high risk of cardiovascular disease

- CRI index:

+ CRI - I > 4.0: have cardiovascular risk

+ CRI - II > 3.0: have cardiovascular risk

- AC index > 2.0: have cardiovascular risk

+ Quantification of ADMA:

Perform quantitative testing of ADMA levels for both control anddisease groups In which, the control group only performed the test atthe time T0, the disease group performed the quantification at boththe time T0 (before transplantation) and the 6th month aftertransplantation

- Patients with ADMA concentration values > 97.5% of the upperquartile of the control group are considered elevated

- Patients with ADMA concentration values < 2.5% lower quartile ofthe control group are considered to have decreased concentration.2.5.3.2 Assessment of changes in several cardiovascular risk factors,atherosclerotic indices and plasma asymmetric dimethylargininelevels in patients 6 months after kidney transplantation

Based on plasma ADMA concentrations before transplantation (T0)and after transplantation (T6) of each patient divided into 3 groups:

- Post-transplant decrease: patients with ADMA levels at T6 < T0

- Constant: patients with ADMA concentrations at T6 = T0

- Increased post-transplant: patients with ADMA levels at T6 > T0

2.6 Enter, manage and process data

Collected data is entered, managed by SPSS 20.0 software, and processed using specialized software STATA 10.0, the references were analized using Endnote X7.

2.7 Ethics

Quantitative testing of ADMA patients is not only paid, the research is conducted with the consent of the patients, the indications for examination and testing comply with the protocol

of the Ministry of Health The study was approved by the Medical Research Ethics Committee of the Military Medical Academy The collected data is only used for conducting research for the thesis topic, not for other purposes Personal information of research subjects as well as the control group is kept confidential in accordance with regulations

CHAPTER 3 RESULTS 3.1 Characteristics of the people participate in the study

Table 3.1 The age and gender of the study subjects

Characteristics Patient Control p

Gende

r

Male (n,%) 82 (73,2) 50 (62,5)

> 0,05Female (n, %) 30 (26,8) 30 (37,5)

9,31

36,60 ±7,84 > 0,05Comment: The ratio of male/female in the disease group and thecontrol group was 2.73/1 and 1.67/1, respectively The mean age ofthe patient group was 36.67 years old and the control group was36.60 years old There was no difference in mean age, male andfemale proportions in the two control and disease groups with p >0.05

Table Error! No text of specified style in document 3 Renal

replacement therapy in ESRD patients

of patients undergoing renal replacement therapy by peritonealdialysis was only 7.2% Only 9.8% of patients are on conservativemedical treatment.

Table 3.7 Hematological and biochemical indices

Hemoglobin (g/L),

(X̅±SD) 101,61 ± 16,61 146,14 ± 10,67Ure (mmol/L), Median

(quartile)

22,60 (17,26 – 30,39)

4,82 (4,08 – 5,45) Creatinin (µmol/L),

Median (quartile)

885,15 (692,3-1078,98)

77,25 (70,81 – 85,84) Uric Acid (µmol/L),

Median (quartile) (338.25 – 563,75)434,5 (287,27 – 373,39)330,80Cholesterol (mmol/L),

TG (mmol/L), Median

(quartile) 1,54 (1,09 – 2,37) 1,33 (0,99 – 1,80)LDL-C (mmol/L),

HDL-C (mmol/L),

(X̅±SD) 1,04 ± 0,31 1,17 ± 0,24Comment: The group of patients had higher values of HST, urea,creatinine, uric acid and TG than controls, however, cholesterol,LDL-C and HDL-C were lower than controls, the difference wasstatistically significant with p < 0.005

3.2 Characteristics of several cardiovascular risk factors, atherogenic indices, plasma ADMA levels and their relationship to clinical and subclinical in patients before kidney transplantation.

Table 3.11 Dyslipidemia of the patient group