Chronic Obstructive Pulmonary Disease Dr. Pawan K . Mangla , M.D., INTENSIVIST & PULMONOLOGIST ISIC & PSRI HOSPITAL Brought to you by IJCP Group of Publications and eMedinewS ( a Daily Medical News Paper)
Why COPD is Important ? • COPD is the only chronic disease that is showing progressive upward trend in both mortality and morbidity • It is expected to be the third leading cause of death by 2020 • Approximately 14 million Indians are currently suffering form COPD* • Currently there are 94 million smokers in India • 10 lacs Indians die in a year due to smoking related diseases *The Indian J Chest Dis & Allied Sciences 2001; 43:139-47
Symptoms Exacerbations Exacerbations Deterioration Exacerbations End of Life Disease Trajectory of a Patients with COPD
“Despite this burden, COPD is a “Cindrella” conditions that receives limited recognition from both patients and physicians” Respiratory Medicine 2002; 96: S1-S31
Obstructive Airway Disease Asthma Explosion in research Revolution in therapy COPD Little research(? neglect) Few advances in therapy
New Definition • Chronic obstructive pulmonary disease (COPD) is a preventable and treatable disease state characterised by airflow limitation that is not fully reversible. • The airflow limitation is usually progressive and is associated with an abnormal inflammatory response of the lungs to noxious particles or gases, primarily caused by cigarette smoking. • Although COPD affects the lungs, it also produces significant systemic consequences. ATS/ERS 2004
Risk Factors • Smoke from home cooking and heating fuel • Occupational dust and chemicals • Gender: More common in men. M:F ratio is 5%:2.7% (in India) • Increasing age • Others: Infection, nutrition and deficiency of a1 antitrypsin
Pathophysiology of COPD • Increased mucus production and reduced mucociliary clearance - cough and sputum production • Loss of elastic recoil - airway collapse • Increase smooth muscle tone • Pulmonary hyperinflation • Gas exchange abnormalities - hypoxemia and/or hypercapnia
Physical signs • Large barrel shaped chest (hyperinflation) • Prominent accessory respiratory muscles in neck and use of accessory muscle in respiration • Low, flat diaphragm • Diminished breath sound
Algorithm for Diagnosis at Primary Care Assess by Pt reporting with respiratory symptoms - H/o exposure to risk factors - Physical examination Sputum for AFB +ve -ve Treat as TB Provisional Diagnosis of COPD Poor response refer to secondary care Treat as COPD National Guidelines for Management of COPD at Primary Care Level
Diagnosis Assessing severity Assessing prognosis Monitoring progression Spirometry
Spirometry • FEV1– Forced expired volume in the first second • FVC – Total volume of air that can be exhaled from maximal inhalation to maximal exhalation • FEV1/FVC% - The ratio of FEV1 to FVC, expressed as a percentage.
COPD classification based on spirometryGOLD 2003 SPIROMETRY is not to substitute for clinical judgment in the evaluation of the severity of disease in individual patients.
Diagnosis Chronic cough/sputum PFTs within normal limits No symptoms Treatment Avoid risk factors(smoking cessation) GOLD Guidelines for COPD Stage 0: At Risk
Diagnosis FEV1 >80% predicted FEV1/FVC <70% With/without symptoms Treatment Avoid risk factors Short-acting bronchodilator PRN GOLD Guidelines for COPD Stage I: Mild
Diagnosis 50% FEV1<80% predicted FEV1/FVC <70% With/without symptoms Treatment Avoid risk factors Regular therapy with 1 bronchodilators Inhaled corticosteroids if significant symptoms and lung function response Rehabilitation GOLD Guidelines for COPD Stage II: Moderate
Diagnosis 30% FEV1< 50% predicted FEV1/FVC < 70% With/without symptoms Treatment Avoid risk factors Regular therapy with 1 bronchodilators Rehabilitation Inhaled corticosteroids if significant symptoms and lung function responseorif repeated exacerbations GOLD Guidelines for COPD Stage III:Severe
Bronchodilators Short-acting b2-agonist – Salbutamol Long-acting b2-agonist - Salmeterol and Formoterol Anticholinergics – Ipratropium, Tiiotropium Methylxanthines - Theophylline Steroids Oral – Prednisolone Inhaled - Fluticasone, Budesonide Pharmacotherapy for Stable COPD
Management based on GOLD Post-bronchodilatorFEV1(% predicted)
“Bronchodilator medications are central to the symptomatic management of COPD” GOLD Report 2003
How Do Bronchodilators Work? • Reverse the increased bronchomotor tone • Relax the smooth muscle • Reduce the hyperinflation • Improve breathlessness
“All guidelines recommend inhaled bronchodilator as first line therapy. The ATS suggest initial therapy with an anticholinergic drug if regular therapy is needed” Chest 2000; 117: 23S-28S
Mode of Action • Cholinergic tone is the only reversible component of COPD • Normal airway have small degree of vagal cholinergic tone (no perceptible effect due to patent airways)
Mode of Action (Contd.) • Airways are narrowed in COPD therefore vagal cholinergic tone has greater effect on airway resistance (Resistancea1/radius4) • Therefore, the need for anticholinergic drugs that will act as muscarinic receptor antagonist and block the acetylcholine induced bronchoconstriction
Mode of Action (Contd.) • Anticholinergics may also reduce mucus hypersecretion • Anticholinergic have no effect on pulmonary vessels, and therefore do not cause a fall in PaO2 Drugs of Today 2002; 38(9): 585-600
“Patients with moderate to severe symptoms of COPD require combination of bronchodilators” “Combining bronchodilators with different mechanisms and durations of actions may increase the degree of bronchodilation for equivalent or lesser side effects’’ GOLD Report 2003
Leading Causes of Death, US (1998) Causes of Death 1. Heart disease 2. Cancer 3. Cerebrovascular disease (stroke) 4. COPD and allied conditions 5. Accidents 6. Pneumonia and influenza 7. Diabetes 8. Suicide 9. Nephritis 10. Chronic liver disease All other causes of death Number 724,269 538,947 158,060 114,381 94,828 93,307 64,574 29,264 26,295 24,936 469,314 Global Obstructive Lung Disease (GOLD) Initiative website (www.goldcopd.com), accessed April 2, 2001.
Percent Increases in Adjusted Death Rates, US, 1965 – 1998 3.0 Coronary Other All Other Stroke COPD Heart CVD Causes 2.5 Disease 2.0 Proportion of 1965 Rate 1.5 1.0 0.5 -64% -59% - 35% +163% - 7% 0.0 1965–1998 1965–1998 1965–1998 1965–1998 1965–1998 Global Obstructive Lung Disease (GOLD) Initiative website (www.goldcopd.com), accessed April 2, 2001.
COPD: Risk Factors • Exposures • Smoking (generally ≥90%) • Passive smoking • Ambient air pollution • Occupational dust/chemicals • Childhood infections (severe respiratory, viral) • Socioeconomic status • Host factors • Alpha1-antitrypsin deficiency (<1%) • Hyperresponsive airways • Lung growth
Differential Diagnosis ChronicBronchitis Emphysema COPD Airflow Obstruction Asthma