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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
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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 Annual Estimate Condition mortality (N) annual cost COPD 100,000 $25 billion Asthma 5000-6000 $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 • Wheezing during auscultation • Prolongation of forced expiratory time • Hyperinflation of lungs • 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 6 h • Improve symptoms and exercise capacity • Safe 3 to 4 times daily • Combining B2-agonists plus anticholinergic drugs provides additional benefit to either drug alone
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 • 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 • Leukotriene antagonists • TNF • Antioxidants • Protease Inhibitors • Antiinflammatory Drugs • 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 long-term 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