Description

• Nicotine sources: cigars, pipes, water pipes, hookahs, cigarettes, electronic cigarettes (e-cigarettes), and smokeless tobacco such as dip, snuff, and chewing tobacco
• Electronic nicotine delivery system (ENDS) use is on the rise.
• E-cigarettes are called e-cigs, vapes, e-hookahs, and vape pens.

Epidemiology

Smoking causes more deaths each year than alcohol use, motor vehicle accidents, illegal drug use, and firearm-related injuries combined.

Incidence

• >2 million new smokers annually in the United States
• More than half of new smokers are <18 years of age (6% initiation rate for teens).
• More than half of individuals who have ever smoked cigarettes have successfully quit.

Prevalence

• Age: highest among those aged 45 to 64 years (16%); gender: male > female (15% vs. 12%)
• Cigarette smoking among adults has declined significantly since the 1960s. Cigarette smoking is responsible for >480,000 deaths per year in the United States, including >41,000 deaths from secondhand smoke exposure. This is about 1 in 5 deaths annually or 1,300 deaths every day.
• Each day, about 2,000 people aged <18 years smoke their first cigarette. Each day, about 1,600 youth try their first cigarette.
• In 2018, 21% of high school students reported current use of e-cigarettes.
• In 2020, ~31 million U.S. adults were current cigarette smokers; this represents 14% of men and 11% of women. In 2019, 14% of all adults (34.1 million people) currently smoked cigarettes: 15.3% in men, 12.7% of women.
• 5% of middle school students report current e-cigarette use.

Etiology and Pathophysiology

• Addiction due to nicotine’s rapid stimulation of the brain’s dopamine system (teenage brain especially susceptible)
• Atherosclerotic risk due to adrenergic stimulation, endothelial damage, carbon monoxide, and adverse effects on lipids
• Direct airway damage from cigarette tar; carcinogens in all tobacco products
• E-cigarettes produce an aerosol by heating liquid nicotine, flavoring, and chemicals. Potential adverse effects of e-cigarettes are related to exposure to nicotine as well as to other vapor components produced by the devices.
• If e-cigarette, or vaping product, use is suspected as a possible etiology of a patient’s lung injury, obtain detailed history regarding:
  • Substance(s) used: nicotine, cannabinoids (e.g., marijuana, THC, THC concentrates, CBD, CBD oil, synthetic cannabinoids [e.g., K2 or spice], hash oil, Dank vapes), flavors, or other substances
  • Substance source(s): commercially available liquids, homemade liquids
  • Device(s) used: manufacturer; brand name; product name; model
  • Vitamin E acetate is strongly linked to the EVALI outbreaks.
  • Most product use-associated lung injury (EVALI) associated with products containing THC

Risk Factors

• Presence of a smoker in the household
• Easy access to cigarettes
• Comorbid stress and psychiatric disorders
• Low self-esteem/self-worth
• Poor academic performance
• Boys: high levels of aggression and rebelliousness; girls: preoccupation with weight and body image

General Prevention

• Most first-time tobacco use occurs before high school graduation; restrict minors’ access to tobacco by limiting tobacco advertisements and encouraging tobacco-free sports initiatives.
• Smoking bans in public areas and workplaces
• Media campaigns
• Health warnings on tobacco products
• Peer education program
• Motivational Interviewing

Commonly Associated Conditions

• Coronary artery disease, cerebrovascular disease; peripheral vascular disease; abdominal aortic aneurysm (AAA)
• Chronic obstructive pulmonary disease (COPD); cancer of the lip, oral cavity, pharynx, larynx, lung, esophagus, stomach, pancreas, kidney, urinary bladder, cervix, and blood; pneumonia, osteoporosis; periodontitis; alcohol use; depression and anxiety, reduced fertility
• E-cigarette use has been associated with several cases of idiopathic acute eosinophilic pneumonia.

Pregnancy Considerations
Smoking during pregnancy can increase the risk of miscarriage, congenital anomalies, stillbirth, fetal growth restriction, preterm birth, and placental abruption. Patients are encouraged to quit smoking completely as the evidence on pharmacotherapy interventions for tobacco smoking cessation in pregnancy is insufficient.

Pediatric Considerations
Secondhand smoke increases the risk for sudden infant death syndrome, acute upper and lower respiratory tract infections, exacerbations of asthma, and otitis media. Nicotine passes through breast milk and decreases the production of milk by suppressing the prolactin levels.