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Jill Williams, MD UMDNJ-Robert Wood Johnson Medical School Alcohol Medical Scholars Program Revised March 26, 2007 Assessment and Pharmacological Treatment of Tobacco Dependence < Slide 1> I. Introduction A. Tobacco use is common and has many devastating effects < Slide 2> 1. ~70 million cigarette smokers in US 2. Number one preventable cause of morbidity/ mortality in US 3. > 500,000 premature deaths/year from tobacco 4. 50,000 deaths (in nonsmokers) from environmental tobacco smoke 5. Tobacco and nicotine differ - Tobacco is the harmful part of smoking, not nicotine. It’s the smoke that kills B. Many smokers want to quit and treatments improve outcomes < Slide 2> 1. 41% of smokers try to quit each year 2. Assessment guides treatment 3. Brief advice from a physician increases quitting 4. Treatments double success rates C. This lecture will cover < Slide 3> Epidemiology and consequences Nicotine pharmacology Assessment Pharmacological treatments II. Epidemiology and consequences of tobacco use < Slide 4> A. Epidemiology 1. >1 billion tobacco users worldwide a. ↑ in developing regions (China, India, Africa, S. America) b. Stable or ↓ in developed nations 2. ~23% of US population smokes cigarettes < Slide 5> a. 3% of physicians b. 70% with mental illness or SUD , c. Smoking prevalence ↓ 1960s, but stable~ last 15 years 3. Tobacco forms a. Cigarettes > 95% of all tobacco use b. Cigar smoking 1). Non-daily use patterns 2). ~5% prevalence; increased > 50 percent since 1990s 3). ↑ in youth, women, minority groups c. Chewing tobacco 1). Loose leaf or snuff 2) 3.5% prevalence (Men use 7x > women) 4. Prevalence ↑ in lower SES 5. Males > females; women ↑since 1950s (lung cancer deaths > breast cancer deaths since 1987) < Slide 6> 6. Recent ↑ in youth smoking (“Pediatric epidemic”) < Slide 7> a. Initiation during grades 6-9 (ages 11-15). 90% of all smokers start before age 18 If begin < 16, 1.6x be dependent 5 million US smokers aged 12-17 years B. Morbidity and mortality < Slide 8> 1. Half of smokers die from a tobacco-caused disease (~ 1 in 5 US deaths) 2. Cancer a. ~90% of lung cancers from smoking 1). #1 cause of cancer deaths in US 2). 15% 5-year survival rate b. Other types < Slide 9> {SOURCE: 2004 Surgeon General Report on the Health Consequences of Smoking} 1). Oral cancers (lip, tongue, mouth, and larynx) 2). Esophagus, cervix, bladder, pancreas, and kidney 3. Causes ~100% COPD 2x ↑ death from stroke/ coronary heart disease C. Other consequences 1. Costs > $100 billion annually a. $50 billion in medical costs b. $50 billion lost productivity 2. Primary cause of fatal house fires III. Assessment and treatment A. Components of tobacco smoke < Slide 10> 1. Smoke > than 4000 chemicals a. Carbon monoxide b. Other toxins 1). Hydrogen cyanide 2). Formaldehyde 3). Ammonia 2. Smoke > 60 carcinogens (benzene, cadmium, nitrosamines, polycyclic aromatic hydrocarbons (PAH)) 3. Environmental Tobacco Smoke (ETS) < Slide 11> a. Smoke from cigarettes of others b. Class1A carcinogen, same class as asbestos c. 50,000 additional deaths/ year in non-smokers (3000 lung cancer) Nicotine pharmacology depends on delivery route < Slide 13> Short half-life (2 hours) Best absorption when smoked 1). Cigarettes (smoking) “perfect” drug delivery device 2) Reaches brain in 10 sec 3). Most reinforcing form c. Binds to nicotinic cholinergic receptors d. Arterial levels 6-10x higher than venous e. Metabolized to cotinine in liver 5. Nicotine researched for possible therapeutic effect < Slide 15> a. Ulcerative colitis b. Alzheimer's disease c. Parkinson's disease d. Tourette's syndrome e. Attention deficit disorder f. Schizophrenia 6. Nicotine safety < Slide 16> a. Not a carcinogen b. Not a risk factor for cardiovascular events, even in people with cardiovascular disease , , c. Risk-benefit ratio supports of using nicotine products over using tobacco d. Smokers misinformed re: safety/efficacy of nicotine B. Assessment guides treatment 1. DSM IV criteria < Slide 18> a. Nicotine dependence 1). DSM not list abuse: Clinically significant psychosocial problems rare 2). ≥ 90% smokers meet dependence criteria 3). 3 or more of 7 DSM dependence criteria a). Persistent desire or unsuccessful efforts to cut down or control use b) Activities given up or reduced c). Use despite a physical or psychological problem d). Tolerance e). Withdrawal b. Nicotine withdrawal < Slide 19> 1) Symptoms a). Dysphoric or depressed mood b). Insomnia c). Irritability, frustration or anger d). Anxiety e). Difficulty concentrating f). Restlessness g). Decreased heart rate h). Increased appetite or weight gain 2). Duration a). Most severe 1-3 days after quitting b). Can last 4 weeks 2. Heaviness of smoking index = measure dependence severity < Slide 20> a. Number of cigarettes per day (cpd) smoked b. Time to first cigarette (TTFC) 1). Smokers awaken in nicotine withdrawal 2). Smoking ≤ 30 minutes of awakening = moderate dependence 3). Smoking ≤ 5 minutes of awakening = severe dependence C. Motivation to quit < Slide 21> 1. 70% of smokers want to quit 2. Few quit successfully without treatment a. 33% of self-quitters remain abstinent for 2 days b. < 5% successful D. Provider’s role in treatment < Slide 22> {SOURCE: PHS Guidelines, Treating Tobacco Use and Dependence: Clinical Practice Guidelines, US Dept Health and Human services} Use 5As for primary care settings (ask, advise, assess, assist, and arrange) a. Ask—identify all tobacco users at every visit b. Advise—urge users to quit c. Assess—determine willingness to quit d. Assist—aid in quitting e. Arrange—follow-up Brief physician advice ↑ quitting More physician counseling is better a. 10% quit rates with < 3 minutes b. 20% quit rates >10 minutes E. Treatments ↑ long-term abstinence Tobacco dependence = chronic condition a. < 25% quit successfully on their first attempt b. Usually 8 quit attempts before successful 2. Pharmacotherapy a first line treatment a. Doubles success b. Recommended for all who try to quit, unless contraindications c. Works even without psychosocial treatments d. Best outcomes: meds + psychosocial IV. Rationale for pharmacotherapy < Slide 24> A. ↓ or eliminate withdrawal B. ↓ reinforcement by nicotine , C. ↓ weight gain when quitting D. Unlearn smoking behaviors E. Manage negative mood F. Cost-effective , 1. Treatment cost per smoker $165 17 2. More cost-effective than mammography, anti-HTN drugs V. First-line/ FDA approved pharmacological treatments A. Poor absorption from nicotine replacement medication (NRT), < Slide 26> 1. Nicotine absorption is pH dependent 2. Lower dose delivered 3. Less reinforcing than smoking 4. Poorly absorbed orally 5. Poor compliance and under dosing common 6. Relative contraindications to NRT 11 < Slide 27> a. Few unable to take nicotine b. With caution in selected populations 1). Recent MI 2). Uses < 10 cigarettes per day 3). Pregnant/breastfeeding 4). Adolescents (Not FDA approved) Side effects NRT a. Usually mild b. Local irritant at site of use c. Systemic side effects less common 1).Dizziness 2). Nausea 3). Headache 8. Start NRT on the quit date (QD) B. Nicotine patch < Slide 28> Slow onset of action 30 min to onset 6 h to peak Continuous delivery 24 or 16 hour dosing Night wearing relieves morning craving but disturbs sleep Given with gradual taper Passive dosing Easy to use Best compliance44 No response to acute craving Side effects Skin 1). Itching, tingling at patch site 2). True rash rare Sleep disturbance, abnormal dreaming Availability and cost OTC $50 for 2 week supply Nicotine gum < Slide 29> Buccal absorption 20-30 min onset of action Reduced with acidic beverages (soda, coffee) Bite and park method improves absorption and reduces side effects Side effects Mild- peppery taste Throat irritation Dyspepsia Jaw soreness Dosing 1 piece an hour ↑ for cravings (up to 24 pieces/ day) 6 weeks than taper Longer more helpful Dose: 2mg < 25 cpd; 4 mg> 25 cpd Limitations TMJ Dental problems, edentulous Availability and cost OTC $50 for 2 week supply Generics available ($25-$35) Nicotine lozenge < Slide 30> Buccal absorption (similar to gum, more discreet) Reduced with acidic beverages Dissolve; don’t chew (15 min) Side effects Mild Throat irritation Dosing 1 piece an hour, ↑ for cravings Max 20 per day 6 weeks than taper Dose based on TTFC instead of number of cpd Dose: 2mg if > 30 mins TTFC ; 4 mg< 30 mins TTFC Availability and cost OTC $80 for 2 week supply No generics Limitations: none Nicotine inhaler < Slide 31> Buccal absorption Oral puffer; inhaler misnomer Reduced with acidic beverages Hand to mouth activity helpful for some Side effects Mild Throat irritation Cough Dosing 6-16 cartridges per day Puff for 20 min Limitations - frequent and continuous puffing (80 puffs =1 cigarette) Availability and cost a. Prescription b. Packaged #42 or #168 cartridges (approx $1/cartridge) c. Not covered by all insurance Nicotine nasal spray < Slide 32> Rapid delivery though nasal mucosa Onset in minutes Modest peak in 10 minutes Side effects Moderate- can lead to discontinuation Sneezing Runny nose, watery eyes Burning in nasal mucosa Risk for bronchospasm (h/o asthma) Tachyphylaxis- remit with continued use Dosing One spray each nostril = 1 dose (2 sprays) Minimum 8 doses/day 1-2 doses/ hr 40 doses/ day max Limitations Side effects High early discontinuation Dependence in 30% + using >6 months , Availability and cost a. Prescription b. Packaged as 4 -10mL bottles c. Cost: $5/day; $45/ bottle d. Not covered by all insurance Bupropion < Slide 33> Pharmacology Zyban SR= Wellbutrin SR Accidental discovery as smoking aid Activating, non-sedating antidepressant Effects on DA and NE Effects as nicotinic receptor antagonist , Side effects Mild to moderate Headache Anxiety, agitation Dry mouth Insomnia Dosing 150 mg x 3-7 days, then ↑ up to 300mg daily Start 2 weeks before quit date 7-12 weeks maintenance up to 6 months 300 mg dose associated with least weight gain (1-2 lbs at 6 mos) Limitations/ contraindications Seizure Eating disorder Current use of Wellbutrin or MAO inhibitors Availability and cost Prescription Reimbursable as Wellbutrin, often not as Zyban Cost $3 per day Efficacy < Slide 34> Nicotine replacement Doubles the likelihood of success in stopping smoking as compared with placebo or no NRT 23 Meta-analysis of 110 randomized trials, 35,000 patients. Odds ratio of 6 months abstinence compared to placebo 25 1). Overall 1.74 2). Gum 1.66 3). Patch 1.74 4). Inhaler 2.08 5). Nasal spray 2.27 6). Lozenge 2.08 Success rates 25-30% at 12 weeks No differences in outcomes in a randomized trial of 4 types of NRT (gum= patch= nasal spray= inhaler) Bupropion Efficacy comparable to NRT or ? slightly higher Efficacy independent of antidepressant properties , Patient preference, cost, tolerability Combination therapy may improve outcomes Nicotine combinations 1). Sustained plus immediate acting for craving relief 2). Improves abstinence outcomes 3). Greater withdrawal relief Nicotine plus bupropion 1). No medication interactions/ precautions 2). Commonly given clinically 3). Efficacy unknown, not well studied Varenicline < Slide 35> Partial nicotine agonist Eliminate reward from smoking Prevent withdrawal symptoms Not addicting 2. 1mg BID dose superior to placebo or bupropion in 12 week trials, 3. Additional 12 weeks prevented relapse in continuation study 4. Most common side effects a. Nausea b. Headache c. Insomnia d. Abnormal dreams VI. 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