What are the side effects of smoking?

Health Effects of Smoking

Smoking is the single largest preventable cause of disease and premature death, negatively impacting nearly every organ system in the body and reducing life expectancy by approximately 10 years compared to non-smokers. 1, 2

Cardiovascular Effects

• Smoking is responsible for approximately 20% of all deaths from cardiovascular disease, including more than 148,000 deaths from active smoking and 35,000 deaths from secondhand smoke exposure 2
• Smoking increases the risk of all types of cardiovascular disease including coronary heart disease, ischemic stroke, and peripheral arterial disease 1
• The relative risk of myocardial infarction in smokers under 50 years is five times higher than in non-smokers 1
• Smoking cessation reduces the risk of death from coronary heart disease by 50% after just one year of abstinence 2
• Smoking increases cardiovascular risk through multiple mechanisms including increased blood pressure, heart rate, narrowing of arteries, and hardening of arterial walls 2

Respiratory Effects

• Smoking is the main risk factor for chronic obstructive pulmonary disease (COPD) and lung cancer 3, 4
• Smoking causes chronic bronchitis, emphysema, and decreased lung function with lower FEV1 levels 4
• Smokers experience increased respiratory symptoms and infections due to impaired immune function in the lungs 4
• Smoking during radiation therapy for lung cancer is associated with significantly decreased locoregional control of the cancer 2
• Smoking increases the risk of postoperative pulmonary complications including pneumonia, failure to wean from ventilator, and reintubation 2

Cancer Risk

• Approximately 30% of all cancer deaths in the United States are attributable to active smoking 2
• Tobacco smoking is causally related to at least 16 types of cancer, including cancers of the lung, oral cavity, larynx, esophagus, stomach, pancreas, liver, bladder, kidney, and cervix 2
• Cigarette smoking causes 85-90% of all lung cancer deaths 2
• Environmental tobacco smoke (secondhand smoke) is responsible for approximately 3,000 lung cancer deaths among nonsmokers annually 2
• Continued smoking during cancer treatment increases the risk of cancer recurrence, with a median relative risk of 1.42 for current smokers compared to never-smokers 2

Surgical Complications

• Smoking negatively impacts outcomes from cancer surgery, affecting postoperative complications, quality of life, length of hospital stay, and mortality risk 2
• Current smokers have higher rates of surgical site infections, pneumonia, failure to wean from ventilator, and other pulmonary complications compared to former smokers and never-smokers 2
• In colorectal cancer patients, postoperative morbidity and mortality rates are higher among current smokers, with a significant dose-dependent effect based on pack-years of smoking 2
• Smoking impairs wound healing and predisposes patients to surgical complications 2
• Hospital stays are longer for current smokers compared to never-smokers across all cancer sites 2

Effects on Cancer Treatment

• Smoking during radiation therapy increases treatment-related complications, including osteoradionecrosis and hospitalization during treatment 2
• Smoking during treatment for cervical cancer is associated with lower cure rates, higher frequency of radiation therapy side effects, and higher rates of severe, irreversible complications 2
• Smoking can exacerbate the risk of anticancer drug-related pulmonary and cardiac toxicities, such as cardiomyopathy and pulmonary fibrosis 2
• Smoking affects the metabolism of certain chemotherapy drugs (including erlotinib, irinotecan, and bendamustine), potentially reducing treatment efficacy 2
• Smoking may increase cancer drug side effects such as weight loss, cachexia, and fatigue 2

Diabetes Risk

• Recent cohort studies suggest that smoking is an independent and modifiable risk factor for the development of type 2 diabetes 2
• Heavy smokers (≥2 packs per day) have a 45-74% higher diabetes incidence rate compared to never-smokers 2
• Quitting smoking reduces the incidence of diabetes to that of nonsmokers after 5 years in women and 10 years in men 2
• Tobacco use may exacerbate the complications of diabetes 2

Effects on Pregnancy and Children

• Smoking during pregnancy is associated with increased complications, especially intrauterine growth retardation 4
• Nicotine exposure during pregnancy can cross the placenta and result in multiple adverse consequences, including sudden infant death syndrome 2
• Children exposed to secondhand smoke have increased risk of asthma and higher and lower respiratory tract illnesses 5
• Secondhand smoke exposure in children can impair lung growth and development 4

Benefits of Smoking Cessation

• Quitting smoking at any age increases life expectancy - those who quit at 30,40, or 50 years gain about 10,9, and 6 years of life expectancy, respectively, compared with continued smokers 1
• Smoking cessation is the only treatment capable of reducing exacerbations and mortality as well as sustainedly improving lung function in COPD patients 3
• In cancer patients, smoking cessation has favorable effects on body weight, performance status, postoperative complications, and mortality 3
• A smoke-free environment improves respiratory disorders in both smokers and those exposed to secondhand smoke 5

Electronic Cigarettes (Vaping)

• While e-cigarettes likely pose less risk than combustible cigarettes, they are not harmless 1
• E-cigarettes contain and emit numerous potentially toxic substances beyond nicotine 1
• Growing evidence shows e-cigarettes can have deleterious effects on the cardiovascular system, respiratory system, and brain 1
• E-cigarette use among youth poses a clear threat to public health with dramatic increases in usage among young people 1