Smoking Pathogenesis

SMOKING CESSATION

Learning Objectives

• Understand the hazards of smoking
• Recognize the health benefits of smoking cessation
• Describe the rationale for treating tobacco dependence
• Explain why tobacco dependence is a chronic disease
• Initiate clinical interventions for tobacco users who are willing to quit as well as users who are not willing to make a quit attempt
• Assist users attempting to quit with strategies designed to prevent relapse

The smoking epidemic

• Smoking represents the most readily preventable risk factor for morbidity and mortality.
• Globally, the prevalence of current use of smoking tobacco among individuals aged 15 years and older is 32.7% among males and 6.6% among females.
• More than an estimated 8 million smoking-attributed deaths occur globally each year.
  Global Burden of Disease Study 2019. Lancet. 2021.

The smoking epidemic

• The relatively recent proliferation of e-cigarette vaping products made these the most commonly used of tobacco products.
• 75% of smokers want to quit.
• < 2% of smokers quit each year.

The smoking epidemic

Effective government policy:

• Bans on tobacco advertising and sponsorship
• Regular price rises
• Stronger public health warning labels
• Smoking bans in all public places.

Prevalence of Smoking in Saudi Arabia

• 2.4-52.3% (median = 17.5%)
• School students 12-29.8% (median = 16.5%)
• University students 2.4-37% (median = 13.5%)
• Adults 11.6-52.3% (median = 22.6%)
• Elderly people 25%
• Males 13-38% (median = 26.5%)
• Females 1-16% (median = 9%)

Most smokers began smoking before age 18 Many people start smoking at an age when they are easily influenced by peers and advertising

Young adults (between the ages 20 – 24 years) Highest smoking rate (27%) Relatively brief smoking history Often identify themselves as “social smokers”

Social smokers are at risk of becoming regular smokers (Gilpin, White & Pierce, 2005

Smoking Health Risks

Short-term

• Shortness of breath
• Worsening asthma or bronchitis
• Increased risk of respiratory infection
• Harm to pregnancy
• Impotence
• Infertility

Long-term

• Heart attack and stroke
• Lung and other cancers
• COPD
• Osteoporosis
• Chronic bronchitis and emphysema
• Need for extended care

Tobacco-based products:

• Cigarettes
• Pipes
• Cigars
• Hookahs (shisha/ narghile/ argileh/ Hubble bubble)
• Chewing tobacco etc.
• Electronic cigarette or E-cigarette.

Protection: Second-hand smoke

• Second-hand smoke:
  Also known as environmental tobacco smoke

• Combination of:

  • Side stream smoke (smoke from the end of a cigarette)
  • Smoke exhaled by the smoker

• 67% of smoke from a burning cigarette is not inhaled by the smoker and ends up in the surrounding environment

• 4000 chemicals have been identified in second-hand smoke

  • 50 of these are known carcinogens

  • Examples:

    • • Arsenic compounds
    • • Benzene
    • • Chromium compounds
    • • Ethylene oxide (chemical to sterilize medical devices)
    • • Vinyl Chloride (chemical used in plastics manufacture)
    • • Polonium – 210 (radioactive species)

What is a cigarette?

• Delivers nicotine to the lungs and brain within 7 sec each time a smoker inhales
• Frequent, small-dose stimulation makes smoking highly addictive
• Most cigarettes contain ≥ 10 mg of nicotine
• Average smoker absorbs 1-2 mg of nicotine per cigarette
• Cigarettes release carbon monoxide which adheres to red blood cells faster than oxygen
  • Reduced oxygen causes increased heart rate

What’s in a Cigarette?

• 4000 toxic chemicals + 40 known cancer-causing substances.
  • Tobacco
  • Carbon monoxide
  • Hydrogen cyanide
  • Nitrogen oxide
  • Ammonia (sub-micron sized particles)
  • Nicotine
  • Benzene
  • Formaldehyde
  • N-nitrosamines

What is Nicotine Dependence?

Chronic Nicotine consumption with the following characteristics:

• Substance abuse
• Continues self-administer substance despite perceived negative effects
• High tolerance towards the substance
• Manifests withdrawal symptoms when trying to stop use.

In assessing a smoker’s degree of dependence, look for the presence of these four characteristics. Craving and withdrawal are indicators of compulsion. Loss of control means the smoker uses more tobacco than he/she wishes to or plans. The degree of difficulty in quitting and the amount smoked are other markers of dependence, as are denying the serious health risks.

Fagerstrom Test for Nicotine Dependence**

Effects of Nicotine

• Highly toxic drug
• Increase HR, BP
• Decrease body temp
• Slows circulation
• Affects appetite
• Increase BMR
• Changes brain activity –
  • Ability to pay attention and brings on euphoria
  • Increases dopamine levels that creates a feeling of pleasure.

affects appetite – possibly due to inhibiting insulin release, leading to hyperglycemia.

BMR: The body is always using energy for essential functions such as building new cells, keeping the heart beating, and breathing, sending messages through the nerves and for warmth).

Nicotine withdrawal syndrome

• acute/uncontrollable need to smoke (craving)
• irritability
• restlessness, anger, anxiety feelings
• tiredness
• increased appetite, especially for sweets and resultant weight gain

Nicotine withdrawal symptoms are caused by suddenly stopping nicotine supply. Nicotine withdrawal can manifest itself in the first 4-12 hours after stopping smoking. manifestations are temporary, reaching maximum intensity in the first 24 to 72 hours and decreasing in the ensuing 3-4 weeks.

• trouble to concentrate and focus memory
• depression
• headaches
• insomnia
• dizziness