Fundamentals of Tobacco Interventions

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Understanding Tobacco Use Disorder

Tobacco use disorder is a complex addiction with many influencing factors. In order to understand this disorder and to provide comprehensive treatment to your client, it is helpful to understand the many factors that contribute to the use and sustainment of tobacco. These factors include environmental, biological, and psychosocial factors or EBB. The EBB framework can also be helpful in guiding screening, assessment, and treatment planning.


Environmental Factors

There are a number of external environmental influencers that impact an individual’s initiation and sustainment of tobacco use. A person’s external environment can be further broken down into several levels:

  • Micro-level: influences within an individual’s immediate environment such as family, friends, social networks.
  • Mezzo-level: influences that extend just beyond a person’s immediate circle such as workplace, schools, communities and healthcare centres.
  • Macro-level: broader influences including national, provincial, and larger areas.
  • Global-level: geo-political, economic, and environmental influencers.

Biological Factors

The following video provides a description of the neurobiology of tobacco use disorder.

When inhaled, cigarette smoke travels through the airways to the lungs. From here, nicotine passes directly through the alveolar epithelium into the bloodstream. Although nicotine can interact with a variety of receptors in numerous tissues, as we will see it is its interaction with specific receptors in the brain that creates the dependence associated with smoking. Within seconds, nicotine is delivered to millions of neurons in the central nervous system. Here within the midbrain, nicotine interacts with the alpha-4 beta-2 nicotinic acetylcholine receptors. Acetylcholine is the natural ligand for these receptors. However, nicotine- also an acetylcholine receptor agonist- has a higher affinity for the alpha-4 beta-2 receptors. Located on postsynaptic neurons, these receptors are comprised of 2 alpha-4, and 3 beta-2 subunits that form a channel for transporting ions through the membrane. When 2 molecules of nicotine, or another ligand, engage binding sites within the receptor the ion channel is activated.

(Image of receptor) Looking into the receptor, we see that it is closed. But activation by ligand triggers internal rods to open the channel for the passage of calcium, sodium and potassium ions. This initiates electrical impulses, generating an action potential. This signal is rapidly transmitted down the axon to the reward area of the brain. Here the impulses stimulate the release of neurotransmitters, including dopamine. Dopamine triggers additional signaling events that stimulate the reward circuit, generating short-lived feelings of well-being, improved mood, and increased attention.

Every time tobacco is used, dopamine levels surge. However, nicotine is eliminated rather rapidly, causing dopamine levels to decline. The result…? A craving for more nicotine! With continued tobacco use, alpha-4 beta-2 nicotinic receptors undergo complex adaptive changes, including upregulation and desensitization. Over time, these and other downstream changes contribute to a stronger need for nicotinic stimulation to achieve the rewards of smoking.

Psychosocial Factors

The psychosocial factors that influence the initiation and sustainment of tobacco use include personality traits and behavioural mechanisms.

Personality traits that are commonly associated with individuals who smoke tobacco include:

  • Impulsivity
  • Neuroticism
  • Rebelliousness
  • Low conscientiousness

Behavioural mechanisms are those led to an individual’s response to stimuli. Examples of behavioural mechanisms include:

  • Youth living with parents who use tobacco are more likely to use themselves.
  • People can be influenced by a group or person they admire.
  • Friends and colleagues who use tobacco can also influence a person’s initiation and sustainment of tobacco use.