Effects of COPD Standardized Management on COPD Exacerbation

Inclusion Criteria: 1. Aged ≥40 years 2. Post-bronchodilator FEV1/FVC \<70% 3. Baseline CAT score ≥10 or history of exacerbation in previous 12 months, defined as any use of oral antibiotics and/or oral or nebulized corticosteroids for increased cough, sputum and dyspnea, or exacerbation requiring hospitalization/ emergency admission. 4. Local residents who live nearby and can be followed up throughout study period 5. Written informed consent Exclusion Criteria: 1. Pregnancy, breastfeeding, or potential pregnancy 2. Primary diagnosis of asthma 3. Having severe cognitive dysfunction 4. Severely ill with less than 12-month life expectancy 5. Patients with alcohol abuse history are excluded as alcoholic individuals may have low adherence to the study. Alcohol abuse is defined as an average alcohol intake \>80 g per day within recent two weeks, or daily intake of ≥40 g alcohol in men, and ≥20 g alcohol in women for more than 5 years. 6. Have participated in similar trials or are undergoing other clinical trials 7. Refuses or unable to give informed consent 8. Plan to move 9. Contraindicated to maintenance medicine. 10. Unstable cardiovascular conditions (e.g., angina, myocardial infarction, ascending aortic aneurysm) that may prevent patients performing spirometry. 11. Relative contraindications to spirometry, including current pneumothorax or planning to undergo thoracic/abdominal, ophthalmic or brain surgeries within next 6 months. 12. Comorbid lung disease including bronchiectasis and tuberculosis, or undergoing anti-tuberculosis treatment 13. Recent exacerbation treated with antibiotics and/or oral or nebulized corticosteroids within 30 days prior to enrolment. 14. Exacerbation requiring emergency admission or hospitalization within 30 days prior to enrolment.