Tobacco Dependence

Tobacco Basics - Puff Stats & Facts

• India (GATS-2): 28.6% adults (267 million) use tobacco.
  • Smokeless tobacco (e.g., Khaini, Gutkha) most common: 21.4%.
  • Smoked tobacco (e.g., Bidis, Cigarettes, Hookah): 10.7%.
• Key Harmful Constituents (beyond Nicotine):
  • Over 7000 chemicals; >70 carcinogens.
  • Major toxins: Tar, Carbon Monoxide (CO), Formaldehyde, Benzene.
  • Potent carcinogens: Tobacco-Specific Nitrosamines (TSNAs), Polycyclic Aromatic Hydrocarbons (PAHs).

⭐ Tobacco use is a leading cause of preventable death and disability in India.

Nicotine's Nasty Knack - Brain Hijack

• Mechanism: Nicotine mimics acetylcholine, binding to nicotinic acetylcholine receptors (nAChRs), primarily in the ventral tegmental area (VTA).
• Reward Pathway Activation:
  • Stimulates dopamine (DA) release in the nucleus accumbens (NAc).
  • Reinforces drug-seeking behavior. 📌 Dopamine Drives Desire.
• Neuroadaptation:
  • Chronic use leads to ↑ nAChRs (especially $\alpha4\beta2$ subtype).
  • Results in tolerance & withdrawal symptoms (e.g., irritability, anxiety).
• Pharmacokinetics:
  • Rapid absorption; quickly crosses the blood-brain barrier.
  • Short half-life: ~2 hours, prompting frequent use to maintain effects.

⭐ The $\alpha4\beta2$ nicotinic acetylcholine receptor subtype is crucial for mediating nicotine's addictive effects and is a key target for some smoking cessation therapies.

Caught in the Cloud - Signs & Scales

• DSM-5 Tobacco Use Disorder: ≥2 criteria in 12 mo: impaired control (craving, ↑use), social impairment, risky use, pharmacological (tolerance, withdrawal).
• Nicotine Withdrawal: Onset: hours, Peak: 24-48h, Duration: weeks.
  • 📌 CRAVING: Craving, Restlessness, Anxiety, Vexation (Irritability), Insomnia, Nervousness, GI upset/↑Appetite.
• Fagerström Test (FTND): Score 0-10.
  • Interpretation: Low (0-3), Moderate (4-5), High (≥6) dependence.
  • Key Qs: Time to First Cigarette (TTFC), cigarettes/day (CPD).

⭐ Time to first cigarette (TTFC) after waking is a strong predictor of nicotine dependence severity in the Fagerström test.

Kicking the Habit - Pills & Patches

⭐ Varenicline has the highest single-agent efficacy for smoking cessation.

Mind Over Matter - Talk & Tactics

Behavioral counseling is a cornerstone for cessation.

• 📌 5 A's Model: (Illustrated above) Ask about use; Advise to quit; Assess willingness; Assist with plan; Arrange follow-up.
• 📌 5 R's Model: For unmotivated smokers, to enhance motivation:
  • Relevance: Personalize reasons to quit.
  • Risks: Outline negative consequences.
  • Rewards: Highlight benefits of quitting.
  • Roadblocks: Identify and address barriers.
  • Repetition: Reinforce at every opportunity.
• Motivational Interviewing (MI): Collaborative approach to enhance intrinsic motivation. Core principles: Express Empathy, Develop Discrepancy, Roll with Resistance, Support Self-Efficacy (EDRS).

⭐ Combining pharmacotherapy with behavioral counseling significantly ↑ quit rates and is the most effective approach.

High‑Yield Points - ⚡ Biggest Takeaways

• Nicotine addiction targets nicotinic acetylcholine receptors (nAChRs).
• Withdrawal symptoms (craving, irritability) peak in 1-2 days.
• Varenicline (partial nAChR agonist) is a first-line pharmacotherapy.
• Bupropion and Nicotine Replacement Therapy (NRT) are also key first-line options.
• The 5 A's (Ask, Advise, Assess, Assist, Arrange) guide counseling.
• Strong links to COPD, lung cancer, and cardiovascular disease.
• Fagerström test quantifies dependence severity.