Highlight HEALTH

Today, the American Cancer Society (ACS) celebrates the Great American Smokeout, an annual event in the U.S. to encourage Americans to quit smoking. According to the U.S. Centers for Disease Control and Prevention (CDC), in 2006 one in five U.S. adults smoked [1]. The Great American Smokeout challenges those people to smoke less or quit smoking for the day. The event also raises awareness of the many effective ways to quit for good.

The ACS has just wrapped up their first ever video contest on YouTube, where they asked people to create videos - one minute or less - to discourage smoking. You can check out the contest winners at the American Cancer Society.

You can also read more about the harmful effects of smoking and tobacco smoke in these articles here at Highlight HEALTH:

• Smoking Duration vs. Intensity and the Impact on Lung Cancer Risk
• Irreversible Gene Expression Changes From Smoking
• Smoking Cessation Timeline: What Happens When You Quit
• Second-hand Smoke Exposure Linked to Psychological Problems in Children

Accept the Great American Smokeout Challenge.
Quit for one day, or quit for good.

References

1. Cigarette smoking among adults–United States, 2006. Centers for Disease Control and Prevention (CDC). MMWR Morb Mortal Wkly Rep. 2007 Nov 9;56(44):1157-61.
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In the U.S., one-quarter of adults 18 years of age and older smoke cigarettes [1]. Smoking is truly a deadly habit. With about 4000 known chemicals in tobacco smoke, more than 50 of them are known to cause cancer. According to the World Health Organization, every six seconds someone in the world dies from tobacco use [2].

How’s this for bad odds: tobacco kills 50% of its regular users. One out of every two regular smokers will die from smoking [2].

In addition, an estimated 200,000 people die every year due to second-hand smoke exposure at work. The United States Environmental Protection Agency estimates that second-hand smoke is responsible for approximately 3000 lung cancer deaths annually among non-smokers [2]. Additionally, new research has linked second-hand smoke exposure to psychological problems in children, including attention deficit disorder (ADHD) and conduct disorder.

The best time to quit smoking is RIGHT NOW. And while quitting is tough, you can start counting the benefits of not smoking in as little as 20 minutes. Here’s what happens to your body when you quit smoking [3-5]:

Why is it so difficult to quit smoking?

In one word … nicotine.

Nicotine is an organic compound known as an alkoloid (meaning a nitrogen-containing ring compound, usually water-insoluble and alcohol soluble) found in the leaves of several species of plants, predominantly tobacco, as well as in lower quantities in several frequently consumed vegetables from the nightshade or Solanaceae family, including tomatoes, potatoes, aubergines (eggplant) and peppers [6]. Nicotine by itself is not carcinogenic [7]. However, it does inhibit UV-induced activation of cell death (a process known as apoptosis) [8], interfering with the body’s ability to destroy potentially cancerous cells.

Nicotine activates a specific type of neurotransmitter receptor - the acetylcholine receptor - an integral membrane protein widely distributed in the brain and neuromuscular junctions that normally responds to the binding of the neurotransmitter acetylcholine. This is nicotine’s addictive property: activation of acetylcholine receptors leads to an increased flow of adrenaline (epinephrine), which increases the heart rate, blood pressure, respiration and glucose levels in the blood.

When smokers try to cut back or quit smoking, they experience nicotine withdrawal. A regular smoker will have nicotine or its by-products present in their body for 3 to 4 days after quitting [9]. Withdrawal symptoms appear within a few hours and peak 24 to 48 hours after quitting [10]. Withdrawal symptoms include tobacco craving, a desire for sweets, increased coughing and impaired performance on tasks that require concentration [10-11]. Most symptoms last an average of one month, but hunger (due to the lack of increased blood glucose) and craving can last 6 months or more [10].

Did you ever smoke? How hard was it for you to quit? How did you do it?

References

1. 2005 National Survey on Drug Use & Health Results. U.S. Department of Health and Human Services. Substance Abuse and Mental Health Services Administration. Office of Applied Studies. 2005.
2. 10 Facts About Tobacco and Second-hand Smoke. World Health Organization.
3. Quitting Smoking: Why To Quit and How To Get Help. National Cancer Institute.
4. Quit Smoking - Smoking Cessation Support - Benefits. American Lung Association.
5. When Smokers Quit - The Health Benefits Over Time. American Cancer Society. Revised 10/25/2006.
6. Siegmund et al. Determination of the nicotine content of various edible nightshades (Solanaceae) and their products and estimation of the associated dietary nicotine intake. J Agric Food Chem. 1999 Aug;47(8):3113-20.
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7. Dasgupta and Chellappan. Nicotine-mediated cell proliferation and angiogenesis: new twists to an old story. Cell Cycle. 2006 Oct;5(20):2324-8. Epub 2006 Oct 16.
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8. Sugano et al. Nicotine inhibits UV-induced activation of the apoptotic pathway. Toxicol Lett. 2001 Dec 15;125(1-3):61-5.
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9. Guide to Quitting Smoking. American Cancer Society. Revised 10/27/2006.
10. Hughes and Hatsumkami. The nicotine withdrawal syndrome: A brief review and update. International Journal of Smoking Cessation. 1992 1:21-26.
11. Hughes, Higgins and Hatsukami. Effects of abstinence from tobacco: a critical review, in Research Advances in Alcohol and Drug Problems, vol 10. Edited by Kozlowski LT, Annis HM, Cappell HD, Glaser FB, Goodstadt MS, Israel Y, Kalant H, Sellers EM, Vingilis ER. New York, Plenum, 1990, pp 317-398.

The first evidence linking mothers’ second-hand smoke exposure while pregnant to their child’s attention deficit disorder (ADHD) and conduct disorder has been published in the current issue of Child Psychiatry and Human Development. ADHD and conduct disorder behaviors are called externalizing psychopathology with symtoms that include aggressive behavior, ADHD, defiance and conduct disorder.

The study compared patterns of psychopathology among three groups of children aged 7 to 15 years, all of whom had significant behavioral and/or emotional problems. Children in group 1 did not experience prenatal smoke exposure. Group 2 mothers smoked during the last two trimsters of pregnancy. Group 3 mothers were only exposed to second-hand smoke at home or at work in the final two trimesters of pregnancy. In total, 171 children (primarily boys) and 133 women participated in the study.

Researchers found that children whose mothers had been exposed to tobacco smoke either by smoking or exposure to second-hand smoke when they were pregnant had more symptoms of ADHD and conduct disorder than children whose mothers did not experience smoke exposure. The children whose mothers had been exposed to tobacco smoke did not show more symptoms of emotional disorders (e.g. depression, anxiety). Researchers controlled for a number of factors including family income, parents’ substance abuse, birth weight and parents’ anti-social behavior. However, second-hand smoke exposure remained the primary predictor of ADHD and conduct disorder.

Nicotine

Nicotine is an alkaloid compound (meaning a nitrogen-containing ring compound produced by a plant, usually water-insoluble and alcohol soluble) in tobacco and is believed to be the cause of these behavior problems in children. Here’s why: the changes observed in receptor-mediated cell signaling in the brain and heart of rats treated with nicotine during pre- or postnatal development mimics those caused by environmental tobacco smoke exposure [1]. Nicotine in tobacco smoke interferes with fetal neurodevelopment, specifically the developing nervous system. In animal models in utero, nicotine alters the pattern of cell proliferation and differentiation by targeting nicotinic acetylcholine receptors in the fetal brain. Cell numbers are reduced and the resulting effect is altered synaptic activity [2]. The changes occur in areas of the brain critical to the development of externalizing psychopathology in humans.

On a side note, a study published earlier this year links prenatal exposure to tobacco smoke with changes in brain physiology associated with basic perceptual skills and affects speech-processing ability in newborn infants [3]. Further work suggests that prenatal and adolescent exposure to nicotine exerts gender-specific effects that are detrimental to auditory and visual attention, along with accompanying changes in the efficiency of neurocircuitry supporting auditory attention [4].

The adverse effects of nicotine involve multiple cellular signaling pathways and affect both immediate developmental fetal brain events and the eventual programming of synaptic competence. Thus, affective and behavioral defects may appear in childhood or adolescence after a period of apparent normality.

The statistics

In the U.S. in 2005, an estimated 60.5 million Americans (24.9% of the population) were current cigarette users. In the 1990s, despite the overwhelming data on adverse health effects, smoking prevalence increased sharply among teenaged girls and until recently, a higher percentage of girls than boys aged 12 to 17 used cigarettes within the past month [5].

Unfortunately, the most recent data available indicates that 22.3% of women 15 to 17 years of age and 26.4% of women 18 to 25 years of age are pregnant and smoke [5]. In addition to the irreparable damage to their unborn children discussed above, women who smoke have an increased risk for developing cancers of the mouth, pharynx, larynx, esophagus, pancreas, kidney, bladder and uterine cervix [6].

What you can do

According to the Surgeon General, there is no risk-free level of exposure to second-hand smoke. Opening a window, sitting in a separate area or using ventilation, air conditioning or a fan cannot eliminate second-hand smoke exposure. Here are some tips to protect yourself and your loved ones:

1. Stop smoking. Get help if you need it, but stop smoking today.
2. Don’t smoke if you’re pregnant. Avoid second-hand smoke exposure.
3. Don’t allow smoking in your home or your car.
4. Ensure that your child’s schools and care facilities are smoke free.
5. Insist on smoke-free sections in restaurants and other public places. Patronize those establishments that are smoke-free.
6. Don’t allow smoking around your children. If someone insists on smoking around your children, leave. Don’t risk your child’s health.
7. Take an active interest in your child’s social life. Ask if your child’s friends smoke. Be aware of who your child hangs out with and if they smoke. Teach your child about the dangers of smoking and why they don’t want to be exposed to it.

References

1. Slotkin et al. Perinatal exposure to environmental tobacco smoke induces adenylyl cyclase and alters receptor-mediated cell signaling in brain and heart of neonatal rats. Brain Res. 2001 Apr 13;898(1):73-81.
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2. Slotkin TA. Fetal nicotine or cocaine exposure: Which one is worse? J Pharmacol Exp Ther. 1998; 285 :931 –945
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3. Key et al. Smoking during pregnancy affects speech-processing ability in newborn infants. Environ Health Perspect. 2007 Apr;115(4):623-9. Epub 2006 Nov 28.
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4. Jacobsen et al. Gender-Specific Effects of Prenatal and Adolescent Exposure to Tobacco Smoke on Auditory and Visual Attention. Neuropsychopharmacology. 2007 Mar 21; [Epub ahead of print].
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5. 2005 National Survey on Drug Use & Health Results. U.S. Department of Health and Human Services. Substance Abuse and Mental Health Services Administration. Office of Applied Studies. 2005.
6. Women and Smoking: A Report of the Surgeon General, 2001. U.S. Department of Health and Human Services. 2001.