Introduction
Every day, more than 3,500 teenagers (<>
What is it?
Smoking is an addiction that currently affects approximately 47 million people in the United States. It has been identified by the American Lung Association as the most important source of preventable morbidity and early mortality worldwide. In the U.S., smoking is responsible for 1 in 5 deaths. Smoking costs the U.S. economy over $193 billion in health care costs and lost productivity each year.
A person who smokes often feels the compulsive need to light up that next cigarette. Many smokers cannot wait until their next cigarette to make the nicotine craving go away.
Tobacco smoke contains many compounds that are harmful to the body. Over 4,000 chemicals, including 60 that have been shown to cause cancer, have been found in tobacco and tobacco smoke. Smoking causes approximately one-third of all cancers, including 90% of all lung cancers. Other chemicals in the smoke cause lung and heart disease.
The following are just a few of the chemicals surprisingly found in cigarette smoke:
- Cyanide
- Benzene
- Formaldehyde
- Methanol (wood alcohol)
- Acetylene (fuel used in welding torches)
- Ammonia
- Poisonous gases including nitrous oxide and carbon monoxide
These chemicals inhaled by a smoker or nonsmoker (via second hand smoke?see below) are known to either cause or worsen the following health problems:
- Cancers: lung, oral, larynx (throat), esophageal, kidney, bladder, pancreas, stomach, colon
- Chronic Obstructive Pulmonary Disease (emphysema and chronic bronchitis)
- Chronic "smoker's cough"
- Asthma
- High blood pressure
- Heart disease
- Stroke
- Peptic ulcer disease
- Gastric Esophageal Reflux Disease (GERD or heartburn)
- Diabetes
Secondhand smoke, also called environmental tobacco smoke (ETS), is smoke inhaled by a person who is in an environment where tobacco smoke is being produced by another person. Secondhand smoke contains the same amount of cancer-causing chemicals as smoke inhaled directly by a smoker. In 1993, the U.S. Environmental Protection Agency determined that there is sufficient evidence that secondhand smoke causes cancer in humans. However, researchers are unsure at this time what amount of secondhand smoke exposure is needed to cause cancer. The current Surgeon General's Report concluded that scientific evidence indicates there is no risk-free level of exposure to secondhand smoke.
Additionally, a study was recently published that coined the term "third-hand smoke." The term is being used to describe the invisible yet toxic brew of gases and particles that cling to smokers' hair and clothing, even furniture cushions and carpeting that lingers long after second-hand smoke has cleared. Researchers have found that eleven of the compounds found in third-hand smoke are highly carcinogenic (may cause cancer). The study shows that increasing awareness of how third-hand smoke harms the health of children may encourage home smoking bans.
According to the Centers for Disease Control and Prevention (CDC), approximately 38,000 deaths occur each year among nonsmokers in the United States as a result of exposure to secondhand smoke. It has also been shown that persons living in a home with smokers are at the highest risk of developing cancer from secondhand smoke. According to the American Cancer Society, sitting in a nonsmoking section of a restaurant for two hours is equal to smoking one and a half cigarettes. In addition, a nonsmoker sitting behind a smoker in a bar for two hours breathes in the equivalent of four cigarettes.
What causes it?
Addiction to smoking is actually caused by the body's addiction to the primary ingredient in cigarette smoke, known as nicotine. Nicotine causes an addiction to smoking in three ways. First, small amounts of nicotine make a person feel pleasant and satisfied, causing the person to want to smoke even more. Secondly, nicotine affects the mood and behavior of a smoker by altering chemicals in the brain. Long-term brain changes induced by continued nicotine exposure result in addiction. Lastly, and often most importantly, withdrawal symptoms, such as nervousness, headaches, irritability, increased appetite, and difficulty sleeping, occur when a person refrains from smoking for a given period of time (usually about 24 hours).
Who has it?
Since tobacco use is an addiction that is self-initiated, anyone could become addicted to tobacco products. However, there are certain groups of people that are more prone to becoming addicted to nicotine. According to the most recent National Health Interview Survey from the Centers for Disease Control and Prevention and the National Center for Health Statistics, in the United States, an estimated 25.9 million men (23.9%) and 20.7 million women (18.1%) are smokers. Smoking is least prevalent among persons older than age 65 (10.0%) and most prevalent among persons 18 to 24 years of age (23.7%), although the prevalence for those 25 to 44 years of age is only just slightly lower (23.2%). Studies have shown that the prevalence of smoking is higher among persons with 9 to 11 years of education (32.6%) compared with persons with more than 16 years of education (7.1%).
Unfortunately, teenage smoking is on the rise. In 2003, approximately 3.6 million Americans 12 to 17 years of age smoked regularly. In 2007, 20% of high school students reported that they were current smokers. On a positive note, in recent years, the percentage of 8th grade students who admitted to smoking has declined from 21% (in 2002) to 9% (in 2003).
What are the risk factors?
Surveys have shown that young adults age 18 to 25 years have the greatest incidence of starting to use tobacco products. The younger you are when you begin smoking, the more likely you are to be an adult smoker. Almost 90% of adult smokers started at or before the age of 19. Teenage use of tobacco products is most often initiated by the need to be accepted by their peers who smoke and the need to feel like they fit in. Some teens have also reported that they began using tobacco products in order to rebel against their parents. Recent research has also shown that teenagers are the most resistant to antismoking messages and campaigns, because they do not fully understand the complications that smoking tobacco can initiate.
The pleasant feeling associated with nicotine use is often helpful to people who want to decrease their stress levels. Consequently, people who have high-stress work environments or difficult family situations may be more likely to use nicotine, at least on an occasional basis.
A few small studies have shown that persons are more likely to begin smoking if a parent smoked. Parents, the most influential role models in children, often dictate the positive and negative behaviors of their children.
What are the symptoms?
Symptoms of high nicotine addiction include but are not limited to:
- Nicotine craving within the first hour of waking
- Having difficulty refraining from smoking in places where it is forbidden
- Smoking more than ten cigarettes per day (although any nicotine use is unhealthy)
- Smoking even when very ill and unable to go to work or get out of bed
Nicotine withdrawal often occurs within 24 hours of refraining from nicotine use. Signs of nicotine withdrawal include:
- Depressed or elevated mood
- Insomnia
- Irritability, frustration, or anger
- Anxiety
- Difficulty concentrating
- Restlessness
- Decreased heart rate
- Increased cravings
- Increased appetite or weight gain
The presence of at least four signs of withdrawal is needed to be diagnosed with nicotine withdrawal. It is important to continually self-monitor for these signs.
Why should you quit?
The US Surgeon General's Report of 1990 detailed a timeline as to how cessation from nicotine improves a person's health status. While this report is somewhat dated, it still holds true today.
- 20 minutes after the last cigarette: heart rate drops
- 12 hours after the last cigarette: the carbon monoxide level in the blood drops back to normal
- 2 weeks to 3 months after the last cigarette: circulation improves and lung function increases
- 1 to 9 months after the last cigarette: coughing and shortness of breath decrease; cilia (tiny hair-like structures that move mucus out of the lungs) begin to function normally again, increasing the ability to clean out the lungs and thus reduce the risk for lung infection
- 1 year after the last cigarette: risk of heart disease is decreased in half compared to a continuing smoker's risk
- 5 years after the last cigarette: risk for having a stroke is the same as a person who never smoked
- 10 years after the last cigarette: lung cancer death rate is about half of a continuing smoker. The risk of cancer of the mouth, throat, esophagus, bladder, cervix, and pancreas decrease as well.
- 15 years after the last cigarette: the risk of heart disease is the same as a person who never smoked.
Five stages of smoking cessation
There are five stages of smoking cessation. These stages can help a person determine how much further he/she must go in order to achieve complete smoking cessation.
- Pre-contemplation: the person has no desire to quit
- Contemplation: the person has a desire to quit but no quitting plan
- Preparation: the person has a desire to quit within one month and has a quitting plan
- Action: the person has quit for one day to six months
- Maintenance: the person has quit for at least six months
Successful treatment of nicotine addiction is a continual process. An addiction is not like an infection where you take a medication and the infection completely resolves in a short amount of time. On average, a person tries to quit smoking eleven different times before becoming successful. Quitting "cold turkey" with no additional help is often only successful in persons who smoke infrequently. People who smoke greater than ten cigarettes per day often require medication and psychological therapy to aid them in successfully refraining from smoking on a permanent basis.
Multiple products are available to help you quit smoking including nicotine replacement aids (e.g. gums, patches) and medications such as Zyban, Chantix, and antidepressant medications. For individuals who are highly addicted to nicotine or who have smoked for many years, combination therapy (eg. nicotine patch plus Zyban) can be tried. However, it's best to try one therapy first and if that therapy fails, then proceed to combination therapy. Therapy needs to be tailored to the individual. Click on the drug class links below to learn more.
Additionally, non-drug therapy is the key to success with smoking cessation. Click on our "Helping Yourself" link above to learn helpful tips to stop smoking.
Finally, some people have found success with alternative therapies such as hypnosis.
Drug classes used to treat Smoking Cessation
- Alpha 4 Beta 2 Nicotinic Acetylcholine Receptor Agonist
- Alpha-2 Agonists
- Nicotine Replacement Therapy
- Tricyclic Antidepressants
- Zyban
What is on the horizon?
An experimental vaccine to help people quit smoking is currently being researched. This vaccine stimulates the body to produce nicotine antibodies that bind to any nicotine that enters a person's blood when he/she smokes. This nicotine/antibody complex is then too large to enter a person's brain, thus preventing the addictive effects of the nicotine from occurring. Small studies so far have reported the vaccine to be safe and well tolerated. However, the effectiveness of the vaccine in helping people to stop smoking has not yet been established. A recent study was just completed that evaluated the safety and efficacy of various dosing levels and dosing frequencies of a nicotine vaccine named NicVAX. The results have yet to be published. There are also two more studies in progress that are studying NicVAX. The vaccine will most likely be used in combination with other smoking cessation drug therapies. It is being considered as a smoking prevention vaccine for people who have never smoked before. The vaccine for the use in smoking prevention has yet to be studied. Once clinical studies of the vaccine for smoking cessation purposes are completed, FDA approval will be needed before manufacture of this vaccine can occur.
Research has pinpointed a specific molecule, the b2 subunit, of the nicotine receptor in the body as a critical component of nicotine addiction. This discovery identifies a potential site for targeting future drug therapy in smoking cessation.
Other recent research has shown that persons with decreased function of the liver enzyme CYP2A6 have a less likely chance of becoming addicted to nicotine. The creation of new medications that decrease function of this enzyme may promote improved smoking cessation.
Many smokers report that they miss the sensory aspects of smoking. Studies using sensory replacement therapy in these patients have shown some promise. Inhalation therapies containing ascorbic acid or citric acid have been tested, both increasing short-term rates of smoking cessation. Further studies of sensory replacement therapy in combination with FDA-approved smoking cessation drug therapy is warranted but has yet to be initiated.
