Evaluation of varenicline as an aid to smoking cessation in UK general practice – a THIN database study

Abstract

Objectives:

Varenicline is a licensed smoking cessation medication in the EU, USA and many other countries worldwide. This study was designed to assess its effectiveness in a UK general practice setting.

Methods:

The main outcome measure was the rate of smoking cessation, defined as the seven-day point prevalence after six months from starting varenicline. Varenicline users were identified from records in The Health Improvement Network (THIN) database. A questionnaire on smoking cessation was sent to patients who commenced treatment close to the selection date (six months prior to the date of questionnaire dispatch).

Results:

The response rate was 26.4%: 193 responses were received. Ninety percent had previously attempted to stop smoking and 87.4% had used nicotine replacement therapy during the previous attempt to stop smoking. The overall smoking cessation rate was 49.5%. There was a strong association between the duration of varenicline treatment and smoking cessation. Patients who reported using varenicline for 9–12 weeks were 11 times more likely to stop smoking than those who completed less than two weeks of treatment. There was some evidence that patients with a longer history of smoking were less likely to stop. No association was observed between smoking cessation and: previous number of cigarettes smoked per day; number of previous attempts to stop smoking; or motivations for stopping.

Conclusions:

Varenicline appeared to be a useful pharmacological aid to smoking cessation in a general practice setting. The observed effectiveness was similar to the efficacy estimates from previously reported clinical trials. However, the response rate was lower than expected and responders tended to be older, more likely to suffer from chronic obstructive pulmonary disease and to live in more affluent areas than non-responders. Responses were self-reported and not clinically validated therefore recall bias may be an issue.

Key words::

• α4β2 nicotinic acetylcholine receptor partial agonist
• Compliance
• Effectiveness
• Smoking cessation
• UK general practice
• Varenicline

Transparency

Declaration of funding

This study was funded by Pfizer Ltd, UK, who reviewed the content of the manuscript.

Declaration of financial/other relationships

K.W. and M.M. have disclosed that they are employed by Pfizer. M.H. and B.T.B. have nothing relevant to disclose.

Some peer reviewers receive honoraria from CMRO for their review work. The peer reviewers of this paper have disclosed that they have no relevant financial relationships.

The study was conducted on behalf of Pfizer by CSD EPIC.

Acknowledgement

Assistance with medical writing was provided by Dr Glenys Bloomfield, Cygnus Biostatistics Ltd, UK, and funded by Pfizer Inc.