Smoking and health Professor Martin Jarvis Department of

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Smoking and health Professor Martin Jarvis Department of Epidemiology & Public Health

Smoking and health Professor Martin Jarvis Department of Epidemiology & Public Health

Smoking as nicotine dependence • Nicotine the driving force • As with other drugs,

Smoking as nicotine dependence • Nicotine the driving force • As with other drugs, complex interplay between pharmacology, learning mechanisms, social and economic influences in determining patterns of use

The major health consequences of smoking • Cancer – lung – mouth, larynx, throat,

The major health consequences of smoking • Cancer – lung – mouth, larynx, throat, oesophagus – bladder, cervix, kidney, pancreas • COPD • Coronary heart disease • Stroke • Peripheral vascular disease • Pregnancy and birth complications

Mortality associated with smoking • At least 320 deaths every day from smoking in

Mortality associated with smoking • At least 320 deaths every day from smoking in the UK, 120, 000 per year • 1/5 all deaths across all ages • 1/4 all deaths in age group 35 -64 years • 1 in 2 lifetime risk for smokers • 7. 5 years average loss of life expectancy • Over half of the difference in risk of death in middle age between professional and unskilled men • 4 million deaths worldwide

Cumulative deaths from tobacco (millions) Scenarios for future deaths from tobacco 520 500 Trend

Cumulative deaths from tobacco (millions) Scenarios for future deaths from tobacco 520 500 Trend 400 300 220 200 70 100 0 1950 1975 2000 Year Source: Peto et al 2025 2050

Smoking is highly addictive • At least 70% of smokers want to give up

Smoking is highly addictive • At least 70% of smokers want to give up • Less than half succeed before age 65 • 40% of heart attack smokers relapse while still in hospital within 2 days of intensive care • 50% of patients with laryngectomies try smoking again • 50% of patients with lung removed for lung cancer smoke again • More than half of heroin and cocaine users and alcoholics rate smoking harder to quit

Addiction

Addiction

Starting point - the cigarette “The cigarette should be conceived not as a product

Starting point - the cigarette “The cigarette should be conceived not as a product but as a package. The product is nicotine. Think of the cigarette pack as a storage container for a day’s supply of nicotine…. Think of the cigarette as the dispenser for a dose unit of nicotine…. . Smoke is beyond question the most optimised vehicle of nicotine and the cigarette the most optimised dispenser of smoke”. William Dunn, Philip Morris, 1972

Nicotine Addiction in Britain Royal College of Physicians Feb 2000 Central conclusion: smoking is

Nicotine Addiction in Britain Royal College of Physicians Feb 2000 Central conclusion: smoking is best understood as nicotine seeking behaviour • “Nicotine delivered rapidly to the brain in cigarette smoke should be recognised as a powerfully addictive drug on a par with heroin and cocaine, and tobacco products should be recognised as nicotine delivery systems. ”

Rating IV nicotine and cocaine: Jones et al (1999) • Compared 3 doses of

Rating IV nicotine and cocaine: Jones et al (1999) • Compared 3 doses of cocaine and nicotine given IV double-blind + saline placebo • Nicotine ‘high’ and ‘rush’ rated stronger than cocaine, also ‘jittery’ • Nicotine frequently misidentified as cocaine, and, at highest dose, an opiate

Nicotine as a drug of dependence • Blood nicotine from cigarettes, snuff (oral and

Nicotine as a drug of dependence • Blood nicotine from cigarettes, snuff (oral and nasal) and cigars very similar • IV nicotine suppresses smoking • Nicotine intakes from different brands of cigarette very similar

Nicotine as a drug of dependence • Nicotine withdrawal syndrome • Effect of nicotine

Nicotine as a drug of dependence • Nicotine withdrawal syndrome • Effect of nicotine replacement on successful quitting

Self-assertion. . . “To account for the fact that the beginning smoker will tolerate

Self-assertion. . . “To account for the fact that the beginning smoker will tolerate the unpleasantness we must invoke a psychosocial motive. Smoking a cigarette for the beginner is a symbolic act. The smoker is telling his world, 'This is the kind of person I am. ' Surely there are variants of this theme, 'I am no longer my mother's child, ' 'I am tough, ' 'I am not a square. ' Whatever the individual intent, the act of smoking remains a symbolic declaration of personal identity. . . ” Philip Morris (Bates no. 1003287836)

. . . and addiction “. . . As the force from the psychosocial

. . . and addiction “. . . As the force from the psychosocial symbolism subsides, the pharmacological effect takes over to sustain the habit. . . ” Philip Morris 1969 document (Bates no. 1003287836)

Addiction -

Addiction -

Factors favouring study of smoking as compared with other drug taking behaviours • High

Factors favouring study of smoking as compared with other drug taking behaviours • High prevalence • Legal • Little stigma, so self-reports largely accurate • Unlike alcohol, excellent biomarker of intake available

Cotinine as a biomarker of nicotine intake • Main nicotine metabolite (70 -80% converted)

Cotinine as a biomarker of nicotine intake • Main nicotine metabolite (70 -80% converted) • Half-life 16 -20 hours • Measurable in saliva, blood or urine • Quantitative measure of nicotine intake: 10 ng/ml cotinine in blood ~ 1 mg nicotine daily

Disadvantage and Smoking • A whole range of indicators of disadvantage predict who smokes

Disadvantage and Smoking • A whole range of indicators of disadvantage predict who smokes • Cigarette smoking prevalence tightly linked to deprivation, mainly because of low rates of quitting in disadvantaged groups

Indicators of socio-economic status • • Occupational class Educational level Housing tenure Car ownership

Indicators of socio-economic status • • Occupational class Educational level Housing tenure Car ownership Unemployment Living in crowded accommodation Single parenthood Divorced or separated

Disadvantage and smoking • Poor people are: – More likely to take up smoking

Disadvantage and smoking • Poor people are: – More likely to take up smoking – Less likely to quit – More heavily exposed to other people’s smoke – Become more nicotine dependent – Much more likely to die prematurely from smoking

Some implications of nicotine addiction for cessation and harm reduction • Ineffective • cutting

Some implications of nicotine addiction for cessation and harm reduction • Ineffective • cutting down • switching to cigars or a pipe • switching to low tar • Effective • Nicotine replacement products

One year success rates by intensity of intervention: • Unaided quit attempt …………………. .

One year success rates by intensity of intervention: • Unaided quit attempt …………………. . . …. 1 -2% • Brief GP advice ………………. . . …… 5% • Brief GP advice + NRT ……………. … 10% • Intensive clinic support ……………. . . 15% • Intensive clinic support + NRT……………. . 20 -30%

Cumulative deaths from tobacco (millions) Scenarios for future deaths from tobacco 520 500 Trend

Cumulative deaths from tobacco (millions) Scenarios for future deaths from tobacco 520 500 Trend 400 300 220 200 70 100 0 1950 1975 2000 Year Source: Peto et al 2025 2050

Cumulative deaths from tobacco (millions) Scenarios for future deaths from tobacco 520 500 If

Cumulative deaths from tobacco (millions) Scenarios for future deaths from tobacco 520 500 If smoking uptake halves by 2020 Trend 400 300 220 200 70 100 0 1950 1975 2000 Year Source: Peto et al 2025 2050

Cumulative deaths from tobacco (millions) Scenarios for future deaths from tobacco 520 500 If

Cumulative deaths from tobacco (millions) Scenarios for future deaths from tobacco 520 500 If smoking uptake halves by 2020 Trend 400 340 300 220 200 If adult smoking halves by 2020 190 70 100 0 1950 1975 2000 Year Source: Peto et al 2025 2050

Conclusions • Nicotine’s legal status and lack of adverse effects on performance have hampered

Conclusions • Nicotine’s legal status and lack of adverse effects on performance have hampered recognition of its status as a drug of dependence • Nicotine is pharmacologically a hard drug, on a par with heroin and cocaine • Cigarette smoking is by far the biggest problem of drug dependence in the UK