According to the World Health Organization, COPD is the third leading cause of death after ischemic heart disease and stroke.. There are estimated 329 million people with COPD worldwide
Trang 1BACKGROUND
1 Rationale
Chronic obstructive pulmonary disease (COPD) is a common respiratory disease worldwide as well as in Vietnam, the incidence and mortality rate increasing with high burdens of treatment costs and causing severe disability According to the World Health Organization, COPD is the third leading cause of death (after ischemic heart disease and stroke) COPD is also one of the 10 incurable diseases worldwide There are estimated 329 million people with COPD worldwide and this number will continue to increase in the coming decades due to increased exposure to COPD risk factors and aging of the population Although the disease is preventable and treatable, diagnostic and treatment guidelines for stable COPD and exacerbations are frequently updated, but implementation is still challenging, especially in the community and primary care settings It’s the fact in Vietnam that not many patients with COPD are properly diagnosed, managed and treated in accordance with the MOH's guidelines at the primary care level, the main reasons are unfavorable geographical, economic and social conditions of the patients, others factors included the limitation of healthcare facilities, equipment, qualifications of health workers and health insurance payment at primary care levels Therefore, intervention in health education and communication to raise awareness for people, patients and health workers about COPD is an immediate and long-term task to coordinate the detection, treatment and prevention of this dangerous disease
2 Scientific meaning and practicality of the dissertation
- Determined the prevalence of COPD in Nghe An, estimate the number of people with COPD in the community, thereby establishing a screening plan and effective COPD management office in the community
- Assess the main risk factors of the disease, determine which risk factors can be prevented, then propose effective prevention methods to reducing the incidence of COPD in the future
- Analyze the clinical characteristics, ventilation function and electrocardiogram findings in COPD patients, then suggest screening people with high risk factors for COPD
- Assess the treatment counseling methods at the community level, contributing to reducing the economic burden on the family and society
On the other hand, raise awareness for patients about adherence to treatment, re-examination to reduce exacerbation and hospitalization
Trang 23 Research objectives
i To determine the prevalence and main risk factors for chronic obstructive pulmonary disease in people aged 40 and over in Nghe
An province, the period of 2017-2019
ii To describe the clinical characteristics, ventilation function and ECG findings among subjects with chronic obstructive pulmonary disease
iii To measure the results of therapeutic interventions for chronic obstructive pulmonary disease in the community
4 Structure of the dissertation
- The dissertation consists of 135 pages (not including the references and appendices) The dissertation consists of 7 parts: Introduction: 2 pages, Chapter 1 Overview: 32 pages, Chapter 2 Subjects and research methods: 25 pages, Chapter 3 Research results 36 pages, Chapter 4 Discussion: 37 pages, Conclusion: 2 pages, Recommendations: 1 page
- The dissertation consists of 33 tables (the results section 31 tables),
17 charts and 6 figures, 212 references including 14 articles in Vietnamese, 198 articles in English The appendix includes research sample, list of enrolled patients, list of intervention-control patients, intervention forms
CHAPTER 1: LITERATURE REVIEW 1.1 Epidemiology of COPD
Epidemiology of COPD worldwide
WHO report shows that, in 2017, there were 56.9 million deaths worldwide, of which 54% died from 10 common causes and COPD was the 3rd leading cause of death According to WHO forecasts, by 2020, COPD will be the third leading cause of death after coronary and cerebrovascular disease Data from studies show that the COPD mortality rate in 2000 was 2.95 million, ranking the fourth leading cause of death Smoking is the second leading risk factor for death with 7.1 million cases, and this is also a major risk factor for COPD Thus, it is predicted that the mortality rate due to COPD will increase, while infectious diseases will tend to decrease
Epidemiology of COPD in Vietnam
An epidemiological study of Ngo Quy Chau et al (2006) in Hanoi showed that the prevalence of COPD for both genders was 4.7% of the population over 40 years old, of which male 7.1% and female 2.5% A recent study by Phan Thu Phuong (2010) on the prevalence of COPD in suburban Hanoi and Bac Giang province, the prevalence of COPD among
Trang 3people over 40 years old was 3.6%, of which male 6.5% and female 1.2% According to Dinh Ngoc Sy et al, in a national COPD epidemiological survey in 2006, the prevalence of COPD among the population aged 40 and over was 4.2%, male 7.1%, female 1.9%, rural areas 4.7%, urban 3.3%, mountainous 3.6%, North 5.7%, Central 4.6%, South 1.9%
1.2 Risk factors of COPD
Smoke: Statistical studies have confirmed that smoking is the
leading cause of COPD According to ATS, approximately 15-20% of smokers have COPD and 80-90% of COPD patients are addicted to
smoking
Environmental pollution and indoor pollution: Doiron D et al
(2019) studying the effect of air pollution on lung function in the UK showed that an increase in the concentration of PM10 and PM2.5 in air has related to the decline in FEV1 (-83.13 mL) and FVC (-73.75 mL), on the other hand, the prevalence of COPD is also higher in areas where the concentrations of PM2.5 and PM10 are above 5 µg/m3 Indoor air pollution also affects lung function and COPD In developing countries, using natural gas in cooking or firewood, straw, coal accounts for 50%, which pollutes the living environment
Exposure to occupational smoke and dust: Occupational
environmental factors play an important role in respiratory disease The risk of COPD related to occupational factors was first widely publicized and accepted in the study results of Schilling et al in the 1960s Subsequent studies have shown that COPD and occupational factors are
closely related
Infections: The development of respiratory tract disease in adults is
related to a history of childhood respiratory disorders, the impact of
pneumonia in young children, and COPD is not well defined
Climate: There is a link between COPD exacerbations and climate
(especially temperature and humidity) It is possible that the high humidity associated with air infections or dry air in cold weather causes the appearance and aggravation of respiratory symptoms, and the number
of COPD exacerbates hospitalized also increases during cold weather
Genetic factors: Deficiency of α1 - antitrypsin is a known risk
factor of genes for COPD Deficiency of α1 - antitrypsin increases the risk of COPD by 30 times However, this protein deficiency only
accounts for less than 1% of cases of COPD
Asthma and airway reactivity: Asthma and airway responsiveness have also been identified as risk factors for COPD
Trang 4hyper-Age and sex: In most epidemiological studies on COPD, the
prevalence, disability level, and death rate increase with age The increased prevalence of COPD in recent years is due to an aging world population and a lower death rate due to cardiovascular diseases and
acute infections
1.3 Pathogenesis of COPD
The pathogenesis of COPD is very complex, so far a number of theories have been mentioned
- Inflammatory reaction of the respiratory tract
- The imbalance of proteinase and anti-proteinase system
- The attack of free oxygen radicals
1.4 Clinical manifestations, evaluation and diagnosis of COPD Clinical manifestations: A chronic cough is often the first
symptom of the disease; Chronic sputum production is common in 50%
of smokers Dyspnea on exertion, progressively worsening over time, chest tightness, shortness of breath, or panting are symptoms that can make a patient worried Chest pain is a common symptom but tests that look for the cause of chest pain in patients often give a negative result
Evaluation: Spirometry is the gold standard for definitive
diagnosis, especially early diagnosis, determination of severity, and monitoring of disease progression Airflow limitation that is irreversible
or only partially reversible with bronchodilator is the characteristic physiologic feature of COPD: post-bronchodilator Gaensler index (FEV1/FVC) <70% Lung x-rays are useful for differential diagnosis Electrocardiogram has prognostic significance as well as assessment of concurrent cardiovascular disease
The diagnosis of COPD is confirmed by the following:
- Confirmed diagnosis of COPD: when Gaensler index after bronchodilator test (FEV1 / FVC) < 70%
- Diagnosis disease severity base on to respiratory function and clinical manifestations
1.5 Methods of epidemiological research
In medical science, there are two basic types of research methods: descriptive and analytical research
Cross-sectional research is now widely used as an analytical study
to test causal hypotheses between exposure and disease, based on findings from cross-sectional studies and the support of other available evidence The advantage of cross-sectional research is that it is easy to
Trang 5implement, inexpensive, but the disadvantage is that it is not possible to determine the chronological order between cause (exposure factor) and consequence (disease), because both of these factors are recorded at the same time
Intervention research: this type of research has great practical
value in medical research The research design must be meticulously rigorous, conducting research in according to the proposal, ethical issues need to be considered and addressed Selection of control group must consider about the living environment and physical condition of the study subjects Consider the measure to be implemented, ability of the study subjects to comply with the study measures or medication used
1.6 The role of Communication for Health Education
Communication for Health Education has 3 important tasks: improving people's knowledge about health; change people's attitudes about health; people's practice of health
There are two methods to conduct communication for health education activities: direct and indirect
1.7 Management of COPD in the community
Outpatient treatment of COPD at a stable stage to avoid exacerbation is a highly effective solution The direct cost of maintaining therapy for a patient with COPD in a stable period per year is only about VND 20 million compared to more than VND 200 million which is the cost to pay for patients who have to be admitted to the hospital for exacerbations This means that we can help reduce costs by 90% if we treat patients with COPD at a stable stage Therefore, to reduce the burden of COPD exacerbation, the most economical solution is to build a standard COPD Outpatient Management Unit at the district level
1.8 Research on treatment adherence of patients with COPD
Treatment adherence is a concept that indicates to which extent a patient's behavior corresponds with the agreed recommendations from a health care provider, including medication use, dietary and/or lifestyle changes There are many factors associated with treatment adherence, including age, gender, education, ethnic, smoking status, amount of medication taken per day, stage of the disease or cost of treatment Different methods of adherence assessment will bring different results Currently there are 2 ways to assess treatment adherence: subjective and objective measure
Trang 6CHAPTER 2 SUBJECTS AND METHODS OF RESEARCH
2.1 Scope, place and time of research
The research was conducted on 4,000 subjects aged 40 and over, distributed over 4 regions of Nghe An province during the period of January 2017 to February 2019
2.1.1 Research subjects
Criteria for selecting research subjects
- People aged 40 and above follow the selected sample size
- People with COPD in the intervention research group: physically and mentally healthy enough, have adequate time to participate in the study
- COPD diagnostic criteria: Airflow limitation that is irreversible or only partially reversible with bronchodilator: FEV1/FVC <0.7 after bronchodilator test (FEV1 increase <200ml and increase <12% after bronchodilator test)
Cross-sectional descriptive epidemiological study with analysis:
+ Determining the prevalence of COPD in people aged 40 and older
in Nghe An
+ Analyzing risk factors of disease
+ Assessing clinical symptoms, analyzing ventilation functions and ECG strips of patients with COPD
Controlled therapeutic counseling research:
Trang 7+ Conducting therapeutic counseling intervention with club activities of patients with COPD within 1 year
+ Cross-sectional survey to evaluate the effectiveness after 1 year of intervention
2.2.2 Research Sample Size
- Formula for calculating cross-section epidemiological study sample size
n =𝑍1−𝛼/22 𝑝(1−𝑝)
𝑑 2 x DE
Of which:
𝑍1−𝛼/2 (Reliability coefficients) = 1,96 (standard percentile scale
at statistical significance level α = 0.05)
p = 0,05 (Estimated prevalence of COPD, take p = 5% according
to previous studies in Vietnam)
d: confidence level (desired accuracy), choose d = 0.01
DE = 2 (Design Effect)
Sample size calculated: n = 3650 people
Adding 10% to eliminate errors of cases of absence or cooperation in the survey, the actual number of subjects needed for the study is n = 4000 people
non Formula to calculate intervention study sample size:
𝑍(𝛼,𝛽)2 = 10,5 (Look in table Z with α = 0.05, β = 0.1)
Sample size calculated: n = 62
In fact, we selected entire 166 COPD patients through epidemiological studies, divided into 2 groups: 83 patients in the intervention group and 83 patients in the control group
2.2.3 Research variables and indicators
- Variables of general information of research subjects: age, age group, gender, education, height, weight, blood pressure
- Variables and indicators of clinical epidemiological research: history of disease, exacerbation, hospitalization, exposure to risk factors, symptoms
Trang 8- Variables and indicators of clinical and laboratory examination: clinical examination, ECG results, ventilation function
- Variables and indicators of intervention research: time of study, time after intervention, symptoms, number of exacerbations, number of hospital admissions, number of follow-up visits, adherence to treatment, amount of medication used, steps to use drugs
2.3 Planning and implementing research
- Staff training
- Prepare for questionnaires
- Research facilities: spirometer, ECG Machine, stethoscope, sphygmomanometer
- Implementing research:
+ Information gathering technique
+ Clinical examination
+ Ventilation functions measurement and results analysis
+ ECG measurement and results analysis
- Intervention research and results assessment:
+ Object, time, place of intervention
+ Implementation steps
+ Content of implementation
+ Assessing the results of intervention
2.4 Research bias and errors
2.5 Data processing methods
The data collected were imported and processed with medical statistical algorithms using the computer software program STATA version 13.0
+ Research results are reported back to patients
Trang 9CHAPTER 3: RESULTS
During the study period, we screened 4,000 people who met the cross-sectional epidemiological research criteria, and identified 166 patients with COPD according to GOLD and MOH’s standards
3.1 Prevalence and risk factors for COPD in people aged 40 and older 3.1.1 Prevalence of COPD
We combine clinical examination, pulmonary ventilation function measurement and bronchodilator test to determine disease The study has identified 166 people with COPD among 4,000 people aged ≥ 40 screened, accounting for 4.15% The proportion of patients diagnosed with COPD for the first time is 93.34%
Table 3.8 Prevalence of COPD by districts, gender Gender
Luu
Non
COPD 399 91,51 580 98,98 979 95,79 Tan Ky
Non
COPD 368 92,23 579 99,31 947 96,44 Tuong
Trang 10The average age of the subjects with COPD was 68.81 ± 10.06, higher than the average age of the group without COPD (60.44 ± 11.18), with p <0.001
3.1.2 The Association between Risk Factors and COPD
Table 3.18 Multivariate logistic regression analysis of risk factors
for COPD
(166)
Subjects (3834) % OR 95%CI Smoking
Kitchen smoke exposure ≥30 years 160 3178 4,79 3,7 1,6-8,7
Occupational dust exposure ≥ 20 years 16 35 45,71 16,3 7,0-38,1
History of respiratory disease 36 185 19,46 2,7 1,6-4,3
+ Smokers with ≥ 30 pack-years are 16.6 times more likely to have COPD than non-smokers, while smokers with 15-30 pack-years and with
< 15 pack-years are at 13.8 times and 5.33 times higher risk of COPD compared to non-smokers, respectively
+ Exposure to cooking fumes ≥ 30 years, exposure to occupational dust for ≥ 20 years is at risk of COPD 3.7 and 16.3 times higher than those who have no contact or less exposure, respectively
+ People with a history of respiratory disease are at 2.7 times higher risk for COPD, men are at 3.2 times higher risk of COPD than women
Trang 11+ The risk of COPD increases with age, people aged 70 and over are 9.1 times more likely to have COPD compared to people aged 40-49
Chart 3.2 Risk factors to COPD 3.2 Clinical and laboratory characteristics of subjects with COPD
The clinical symptoms of COPD subjects such as cough, sputum production and dyspnea account for a high proportion (62.65%, 52.41% and 45.78%) The asymptomatic group accounted for 15.06%
Subjects with COPD most often encountered in subgroup A accounted for 45.22%, subgroup B accounted for 37.35% C and D subgroups account for less than 5%
Chart 3.4 Classify COPD according to GOLD 2019 (n = 166)
Subjects with COPD had hypertension accounted for 26.51% (systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90mmHg) Lung examination with decreased breath sounds and increased resonance to percussion accounted for respectively 60.84% and
054%
037%
Subgroup B (n=62)Subgroup C (n=6)Subgroup D (n=8)
Trang 1254.22% Wheezes, crackles at the lung bases accounting for 25.9%, tachypnea with > 20 times/minute accounts for 13.25%
Ventilation function of the COPD group has decreased, manifested in obstructive ventilatory disorder with average FEV1/FVC ratio was 54.8% ±
10 after bronchodilator test, FEV1% was 70.4 (% of theoretical value) The indicators of small airway obstruction are also significantly reduced Comparing the measured results of ventilation function of the COPD subjects after bronchodilator test, the indicators increased very little or not Subjects with COPD encountered the most in the GOLD 2 stage accounting for 45.78%, followed by GOLD 1 accounting for 32.53% GOLD 4 stage only accounted for 3.01%
Chart 3.5 Classification of airflow limitation severty in COPD based
FEV1/FVC (%) MMEF (% of predicted)
FEF75 (% of predicted)
FEF50 (% of predicted)
FEF25 (% of predicted)