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Behavioural treatments to stop smoking before surgery reduce complications after surgery

Thomsen T, Villebro N, Moller AM Interventions for preoperative smoking cessation. Cochrane Database Syst Rev. 2014;3:CD002294.

Review question

Does helping people to quit smoking before they have elective surgery result in fewer complications after surgery?


People who smoke are more likely to have complications after surgery. Several treatments help people to stop smoking, including written materials, brief advice, counselling, and medications. Providing support to stop smoking before elective surgery may reduce complications after surgery.

How the review was done

The researchers did a systematic review, searching for studies published up to January 2014. They found 13 randomized controlled trials with 1210 people. The trials included:

  • people of any age who were having elective surgery, and
  • support to stop smoking in the form of brief or intensive behavioural treatments or medications that started at least 48 hours before surgery.

What the researchers found

There were too few studies on medications to combine the results.

Behavioural treatments were brief or intensive (that is, included weekly counselling sessions for 4 to 8 weeks).

Compared with the control group:

  • about 27 fewer people out of 100 had complications 4 weeks after surgery in the intensive treatment group, but there was no difference in complications with brief treatment;
  • about 46 more people out of 100 in the intensive treatment group and about 12 more out of 100 in the brief treatment group had stopped smoking at the time of surgery; and
  • about 21 more people out of 100 in the intensive treatment group had stopped smoking after 12 months, but there was no difference in stopping smoking with brief treatment.


Helping people to stop smoking with intensive behavioural treatment that starts before surgery reduces complications after surgery and increases the number of people who stop smoking at the time of surgery and after 1 year.

Intensive or brief behavioural treatment vs control to stop smoking before elective surgery


Type of treatment

Number of trials (people)

Rate of events with behavioural treatment

Rate of events with control

Absolute effect of behavioural treatment

Postoperative complications at 4 weeks


2 trials (210 people



About 27 fewer people out of 100 had complications



4 trials (493 people



No difference in effect

Stopped smoking at time of surgery


2 trials (210 people)



About 46 more people out of 100 stopped smoking



7 trials (1,411 people)



About 12 more people out of 100 stopped smoking

Stopped smoking at 1 year


2 trials (209 people)



About 21 more people out of 100 stopped smoking



2 trials (341 people)



No difference in effect*

*Although the rates for the 2 groups look a little different, the differences were not statistically significant. This means that the differences could simply be due to chance rather than due to the different treatments.

Related Topics


Control group
A group that receives either no treatment or a standard treatment.
Randomized controlled trials
Studies where people are assigned to one of the treatments purely by chance.
Systematic review
A comprehensive evaluation of the available research evidence on a particular topic.

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Related Web Resources

  • Patient education: Quitting smoking (Beyond the Basics)

    UpToDate - patient information
    There are many strategies available to help you quit smoking. Start by picking a quit date. Consider speaking with a health care provider for advice, seeking in-person or telephone support, making behavioural changes, and using different medications such as varenicline, bupropion, or nicotine replacement therapy.
  • Quitting Smoking: Should I Use Medicine?

    This patient decision aid helps people who smoke or use other tobacco products decide on whether or not to use medicine to help quit smoking by comparing the benefits, risks and side effects of both options.
  • Texting 2 quit - Using mobile phones to support people quit smoking

    Evidently Cochrane
    Support, in the form of education and nicotine replacement therapy, can increase your chances of quitting smoking. Counselling and text message support via mobile phone is a promising way to manage nicotine cravings. More research is needed as technology options change.
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