Effect of extended counseling on smoking cessation

I’ve talked before about the effect of longer duration of treatment (either pharmacological or counseling or both) on success in quitting smoking. Although the evidence is generally consistent with the idea that more is better (including over a longer time period), I’m always interested in new studies that test the hypothesis that providing treatment over a longer duration leads to higher quit rates.

One such study, by Joel Killen and colleagues at Stanford School of Medicine, was published in the journal “Addiction” this month. They recruited 304 adult smokers who wanted help to quit. Everyone received the same pharmacotherapy: Bupropion SR plus the nicotine patch for 8 weeks. Everyone also attended 6 counseling appointments over the first 6 weeks. At 8 weeks, 56% of both groups were not smoking. But half of the sample (randomly selected) were given another 4 half-hour counseling appointments up to week 20, whereas the other half were given 4 five-minute telephone calls in which they were given general encouragement.

The main finding was that 20 weeks after the target quit date, 45% of those offered extra face-to-face counseling were still quit, as compared with 29% of those offered only the brief telephone calls from week 6 to week 20. This suggests that extended counseling produces higher medium-term quit rates.

The type of counseling used in this study is called “cognitive-behavior therapy” which focuses on identifying triggers for craving and smoking (including thoughts as potential triggers) and developing ways to manage these. The study also measured adverse events during the pharmacotherapy. Some symptoms were very common (e.g. insomnia: 58%, headache: 38%), and some less so (e.g. vivid dreams 14%, anxiety 13%). One participant experienced a severe adverse event, requiring hospitalization for depression.

All the participants were followed up at 52 weeks (i.e. after another 32 weeks with no treatment). By this time the difference between the groups was smaller, with 35% of those who had been offered extended counseling to 20 weeks, still quit, compared with 27% of those offered only brief telephone counseling to 20 weeks. It looks as though the extended counseling may have helped some people stay quit. However, after this stopped (i.e. at 20 weeks) some of those people relapsed to smoking. The results of this study are consistent with those of a randomized trial by Dr Sharon Hall who found that smokers who received both extended counseling for a year and extended medication for a year had a 50% quit rate after 52 weeks.

Not all smokers want or need extended duration treatment (i.e. beyond 6-12 weeks), but it is clear that participation in treatment will increase the chances of successfully quitting smoking, and the longer a person stays engaged in treatment, the less likely they will be to relapse.

Labels: CBT, counseling, extended, jonathan foulds, randomized trial, smoking cessation

Permalink | 0 Comments| Email Post

Post your comment

Carbon monoxide in cigarette smoke

Carbon monoxide (CO) is a clear, odorless gas that is produced by burning any carbon-based substance. So when tobacco is burned and inhaled, one of the 4,000 or more chemicals that enters the body is CO. When the smoke is inhaled into the lungs, CO is rapidly absorbed into the blood stream. CO binds to the hemoglobin in the red blood cells 200 times more effectively than oxygen does. The result is that many of these blood cells that were designed to carry oxygen to different parts of the body, instead bind to the CO, forming carboxyhemoglobin (COHb). This means that the heart has to do more work to supply the necessary amount of oxygen to the body. There is good evidence that high levels of carbon monoxide in the blood of smokers is one of the main factors causing smokers to have increased rates of cardiovascular diseases (such as angina and heart attacks). Other factors include platelet aggregation increasing the “stickiness” in the blood, stimulated by oxidant gases in cigarette smoke, and increased myocardial oxygen demand caused by nicotine. But it is clear that the reduced oxygen supply caused by carbon monoxide is a major factor. For example, increasing blood CO levels (either by smoking non-nicotine cigarettes or inhaling CO) has been shown to reduce the amount of exercize required to cause angina (chest pain) in patients with a history of angina.
(see: http://circ.ahajournals.org/cgi/content/abstract/61/2/262 )

Tobacco smoking is by far the largest determinant of CO levels in the blood, with smokers typically having blood COHb levels around ten times higher than non-smokers. So the idea that you might as well smoke because there is so much pollution in the air anyway is just nonsense. See this link for a study of this in a population sample:
http://www.biomedcentral.com/1471-2458/6/189

Decades ago the only way to measure how much smoke and CO someone had absorbed was to take a blood sample and send it to the lab for analysis. Nowadays we know that a quick and simple breath test can provide an accurate measure of CO absorption, that correlates almost perfectly with a measure of blood carboxyhemoglobin. So most smoking cessation clinics now use a CO monitor when assessing smokers to provide an estimate of how much smoke they are inhaling, and also as a way to monitor progress in treatment. At the Tobacco Dependence Clinic at UMDNJ-School of Public Health we measure exhaled CO at every appointment, just as most family doctors measure your blood pressure at every appointment. We typically find that at assessment (while still a smoker) patients have an exhaled carbon monoxide concentration of around 20 parts per million (ppm). But this can vary from just below 10 ppm to over 50 ppm for someone who has been smoking heavily recently. The good news is that when a smoker quits smoking completely, their exhaled CO levels drop to those of a non-smoker fairly quickly. When we see a patient a week after they have stopped smoking, their exhaled CO level will typically be down to zero, 1 or 2 ppm, compared to around 20 ppm at assessment . This shows that the heart is having to do less work to supply the body with necessary oxygen, and demonstrates an almost immediate improvement in health and cardiovascular risk after quitting smoking.

Medical doctors would do well to routinely measure exhaled carbon monoxide in their patients just the same way that they routinely measure blood pressure. The CO measure is a better indicator of future health outcomes and more important to get down to normal (non-smoking) levels.

A number of companies supply breath CO monitors. I’m not endorsing any of these, nor have I any financial relationships with any of them…just providing links for health professionals who may consider using a breath CO monitor in their clinical work:
http://www.bedfontusa.com/carbonmonoxide.html
http://www.testbreath.com/co.asp
http://www.hansonmedicalsystems.com/products/carbon-monoxide.html
http://www.micromedical.co.uk/products/proddetail3.asp?spiro_id=31

For a more comprehensive description of the effects of smoking and tobacco smoke pollution on health, check out this recent paper:

Foulds J, Delnevo C, Zeidonis D, Steinberg M. Health Effects of Tobacco, Nicotine, and Exposure To Tobacco Smoke Pollution. Chapter In, Brick,J (Ed): Handbook of the Medical Consequences of Alcohol and Drug Abuse pp423-459. Haworth Press, Binghamton, NY. 2008

It can be downloaded for free from: http://www.tobaccoprogram.org/staffarticles.htm

Labels: carbon monoxide, carboxyhemoglobin, cardiovascular health, cigarette smoking, jonathan foulds, smoking cessation

Permalink | 2 Comments| Email Post

Post your comment

UK National Smoking Cessation Conference

Probably the best conference on smoking cessation over recent years has been the UK National Smoking Cessation Conference. The UK is probably the only country to have a national and fairly comprehensive smoking cessation service involving widespread access to trained smoking cessation counselors, access to low cost smoking cessation medicines (via the UKs National Health Service), as well as telephone and internet help. As a result, this conference is the largest gathering of smoking cessation counselors in the world, and also attracts many attendees and speakers from other countries.

It consistently has very lively speakers and many of the presentations are available online with the full slides and audio recording. The 2008 conference just became available online and includes many interesting presentations. For example, an interesting slide show by Rachna Kasliwal describing results of a study of adverse events in patients using Chantix is available at: http://www.uknscc.org/2008_UKNSCC/speakers/rachna_kasliwal.html

An interesting debate on the topic;
“Debate: This house believes that hypnotherapy and acupuncture should be treatments provided by NHS Smoking Services” is also available with full audio and slides at:
http://www.uknscc.org/2008_UKNSCC/speakers/debate.html

I also thought the presentation by Dr Paul Eveyard on “Does stopping smoking mean putting on weight?” was very interesting. The audio recording and his slides are available at:
http://www.uknscc.org/2008_UKNSCC/speakers/paul_aveyard.html

The full archive of each conference from 2005-2008 is now available online at:
http://www.uknscc.org/index.html

It provides an excellent source of information from leading experts on all aspects of stopping smoking.

Labels: cessation, cigarette smoking, conference, jonathan foulds, UK

Permalink | 5 Comments| Email Post

Post your comment