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CHRONIC OBSTRUCTIVE PULMONARY DISEASE UPDATE 2002 O. D. Polk, Jr., M.D. Assistant Professor of Medicine Howard University College of Medicine IMPACT OF COPD IN THE US Affects 21.7 million Americans The fourth leading cause of death – 112,000 deaths in 1998 Annual cost >$30 billion – $14.7 billion in direct healthcare costs – $15.7 billion in indirect healthcare costs It is estimated that by 2020 COPD will be the third leading cause of death in the world Data on file (analysis of NHANES III data), GlaxoSmithKline. American Lung Association. Fact sheet: chronic obstructive pulmonary disease (COPD). Murphy SL. National Vital Statistics Reports; 48(11); 2000. Murray CJL and Lopez AD, eds. The Global Burden of Disease. Vol. 1. 1996:362. COPD VS ASTHMA Condition Annual mortality (N) Estimate annual cost COPD Asthma 100,000 5000-6000 $25 billion $12 billion Martin RJ. American Academy of Allergy, Asthma, and Immunology 56th Annual Meeting; March 4, 2000; San Diego, Calif. DEFINITION OF COPD Airflow limitation that is not fully reversible usually progressive Chronic abnormal inflammatory response to environmental pollutants irritants tobacco smoke American Thoracic Society. Am J Respir Crit Care Med. 1995;152(suppl, pt 2):S77-S120. DIFFERENTIAL DIAGNOSIS American Thoracic Society. Am J Respir Crit Care Med. 1995;152(suppl, pt 2):S77-S120. RISK FACTORS FOR COPD Tobacco smoking (80% to 90%) Passive smoking Ambient air pollution Hyperresponsive airways Exposure to occupational dusts and chemicals Indoor/outdoor air pollution Alpha1-antitrypsin deficiency (<1%) American Thoracic Society. Am J Respir Crit Care Med. 1995;152(suppl, pt 2):S77-S120. Mahadeva R and Lomas DA. Thorax. 1998;53:501-505. Global Initiative for Chronic Obstructive Lung Disease. NHLBI/WHO Workshop Report. April 2001. NIH publication 2701. GENETIC RISK FACTORS FOR COPD Accelerated decline in lung function 15% of whites 5% of Asians Alpha-1-Antitrypsin Deficiency (PiZZ) Gentic polymorphisms of the TNF, cytochrome p450, and miocrosomal epoxide hydrolase ALPHA1 –ANTITRYPSIN DEFICIENCY (AAT) Patients with emphysema: <1% Common variants: S and Z Point mutations in alpha1-antitrypsin gene S-variant (264GluVal) in 28% of Southern Europeans Alpha1-antitrypsin levels = 60% no pulmonary effects Z-variant (342Glu Lys) is associated with severe deficiency Levels 10% of normal Accumulation of alpha1-antitrypsin in the rough endoplasmic reticulum of the liver Predisposed to juvenile hepatitis, cirrhosis, and hepatocellular carcinoma Mahadeva R and Lomas DA. Thorax. 1998;53:501-505. PATIENT SELECTION FOR SCREENING FOR THE DIAGNOSIS OF AAT Onset of COPD before age 50 COPD without smoking history Family history of COPD under age 50 Smoker with family history of COPD Young adult asthmatic unresponsive to therapy Patient with predominant lower lobe emphysema PATHOPHYSIOLOGY OF COPD Hallmark – limitation of expiratory flow with relative preservation of inspiratory flow Bronchial hyperresponsiveness – strong predictor of progression of airway obstruction Nonuniform ventilation Hyperinflation Increased work of breathing and dyspnea CLINICAL FEATURES OF COPD Typical smokers—mean 20 cigarettes/day for 20 years Usually present in fifth decade of life with productive cough or acute chest illness Dyspnea with exertion History of wheezing and dyspnea may lead to an erroneous diagnosis of asthma SYMPTOMS OF COPD Chronic cough Sputum production Breathlessness (dyspnea with exertion) Wheezing American Thoracic Society. Am J Respir Crit Care Med. 1995;152(suppl, pt 2):S77-S120. Global Initiative for Chronic Obstructive Lung Disease. NHLBI/WHO Workshop Report. April 2001. NIH Publication 2701. PHYSICAL EXAMINATION FOR COPD Airflow obstruction Hyperinflation of lungs Wheezing during auscultation Prolongation of forced expiratory time Low diaphragmatic position Decreased intensity of heart and breath sounds Severe disease Pursed-lip breathing Use of accessory respiratory muscles Retraction of intercostal spaces American Thoracic Society. Am J Respir Crit Care Med. 1995;152(suppl, pt 2):S77-S120. Global Initiative for Chronic Obstructive Lung Disease. NHLBI/WHO Workshop Report. April 2001. NIH Publication 2701. COPD – MANAGEMENT Smoking Cessation Pharmacologic Therapy Oxygen Therapy Pulmonary Rehabilitation Nutrition and COPD Noninvasive Positive Pressure Ventilation Surgery for COPD Lung Volume Reduction Surgery (LVRS) Lung Transplantation COPD RISK and SMOKING CESSATION Fletcher C and Peto R. Br Med J. 1977;1:1645-1648. SMOKING CESSATION Smoking cessation is the only measure that will slow the progression of COPD (the Lung Health Study) The presence of respiratory illness such as COPD is not a motivator for smoking cessation Physician-delivered smoking cessation interventions can significantly increase smoking abstinence rates SMOKING CESSATON INTERVENTION Physician Intervention – set a quit date Refer to group smoking cessation clinics Pharmacologic therapy with nicotine replacement therapy (NRT) in highly dependent smokers Smokes a pack or more per day Requires 1st cigarette within 30 min of waking up Finds it difficult refraining from smoking in places where it is forbidden Consider therapy with bupropion alone or in combination with NRT HOWARD UNIVERSITY CANCER CENTER Tobacco Control Program Ongoing Clinical Trial involving Smoking Cessation We are recruiting patients Call 202-865-4036 202-806-5293 PHARMACOLOGIC THERAPY Bronchodilators Short-acting Long-acting Corticosteroids Mucolytics Antibiotics SHORT-ACTING BRONCHODILATOR DRUGS Beta2-agonists and anticholinergics Variable onset of action with duration of 4 to 6h Improve symptoms and exercise capacity Safe 3 to 4 times daily Combining B2-agonists plus anticholinergic drugs provides additional benefit to either drug alone SHORTACTING BRONCHODILATORS LONG-ACTING BRONCHODILATOR DRUGS Drugs Salmeterol Formoterol Theophylline Oral beta2-agonists Duration of action usually lasts 12-24 h Commonly used as maintenance therapy in COPD SYSTEMIC CORTICOSTEROIDS 10 TO 20% of patients with chronic COPD improve Responders have more eosinophils in induced sputum and bronchial biopsy Treatment of hospitalized patients Fewer treatment failures Shorter stays More hyperglycemia Two (2) weeks of therapy is sufficient INHALED CORTICOSTEROIDS No short-term benefit Long-term use may Improve lung function minimally Improve 6-muinute walk test Reduce moderate and severe (but not mild) COPD exacerbations MUCOLYTICS Variable effects in patients with COPD Ineffective at shortening the course or improving outcomes of patients with acute exacerbations ANTIBIOTICS Multiple trials favor the use of antibiotics for acute exacerbations of COPD Worsening dyspnea Increased sputum volume Sputum purulence There is no evidence that prophylactic antibiotics prevent acute exacerbations. OXYGEN THERAPY IN COPD OXYGEN THERAPY Two controlled trials – MRC and NOTT Death rates are lower Quality of life indexes improved Used for at least 15 hours/day Oxygen should be prescribed when Arterial PaO2<55 mmHg or SaO2<88% PaO2 56 to 59 mmHg ECG evidence of p pulmoonale Pedal Edema/CHF Secondary erythrocytosis PULMONARY REHABILITATION Improves dyspnea Improves QOL scores Reduces the number of hospitalizations and days in the hospital Effects on survival are not definite NUTRITION AND COPD Malnutrition occurs in 1/4 to 1/3 of patients with moderate to severe COPD Depletion of fat mass and fat-free mass Elevated resting energy expenditure Nutritional supplements alone do not reverse weight loss Megestrol acetate stimulates weight gain and ventilation in underweight COPD patients but did not improve respiratory muscle function SURGERY FOR COPD Lung volume reduction surgery (LVRS) Mortality 0 to 6% 30 days postop Mortality 0 to 8% 6 months postop Ongoing trials will provide cost-benefit analysis Resection of large bullae Lung Transplantation Procedure is costly Limited lack of organs Requires prolonged immunosuppression NEW TREATMENTS Mediator Antagonists Protease Inhibitors Antiinflammatory Drugs Leukotriene antagonists TNF Antioxidants Phosphodiesterase 4 inhibitors Drug Delivery COPD: KEY POINTS Smoking cessation is extremely important. None of the existing medications for COPD (with the exception of oxygen) are known to modify the longterm prognosis of this disease Pharmacotherapy for COPD is used for the overall management of the disease (including improvement of lung function and QOL) Bronchodilator medications are central to the symptom management of COPD. They are given on an as-needed basis or as maintenance therapy