1 BACKGROUND 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 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 2 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 Structure of the dissertation - The dissertation consists of 135 pages (not including the references and appendices) The dissertation consists of parts: Introduction: pages, Chapter Overview: 32 pages, Chapter Subjects and research methods: 25 pages, Chapter Research results 36 pages, Chapter Discussion: 37 pages, Conclusion: pages, Recommendations: page - The dissertation consists of 33 tables (the results section 31 tables), 17 charts and 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 people 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 PM 10 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 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 hyper-reactivity: Asthma and airway hyperresponsiveness have also been identified as risk factors for COPD 4 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)