Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Randomized Controlled Trial
. 2012 Jul 20:345:e4708.
doi: 10.1136/bmj.e4708.

Effect of communicating DNA based risk assessments for Crohn's disease on smoking cessation: randomised controlled trial

Gareth J Hollands  1 , Sophia C L Whitwell, Richard A Parker, Natalie J Prescott, Alastair Forbes, Jeremy Sanderson, Christopher G Mathew, Cathryn M Lewis, Sally Watts, Stephen Sutton, David Armstrong, Ann Louise Kinmonth, A Toby Prevost, Theresa M Marteau
Affiliations
Randomized Controlled Trial

Effect of communicating DNA based risk assessments for Crohn's disease on smoking cessation: randomised controlled trial

Gareth J Hollands et al. BMJ. .

Abstract

Objective: To test the hypothesis that communicating risk of developing Crohn's disease based on genotype and that stopping smoking can reduce this risk, motivates behaviour change among smokers at familial risk.

Design: Parallel group, cluster randomised controlled trial.

Setting: Families with Crohn's disease in the United Kingdom.

Participants: 497 smokers (mean age 42.6 (SD 14.4) years) who were first degree relatives of probands with Crohn's disease, with outcomes assessed on 209/251 (based on DNA analysis) and 217/246 (standard risk assessment).

Intervention: Communication of risk assessment for Crohn's disease by postal booklet based on family history of the disease and smoking status alone, or with additional DNA analysis for the NOD2 genotype. Participants were then telephoned by a National Health Service Stop Smoking counsellor to review the booklet and deliver brief standard smoking cessation intervention. Calls were tape recorded and a random subsample selected to assess fidelity to the clinical protocol.

Main outcome measure: The primary outcome was smoking cessation for 24 hours or longer, assessed at six months.

Results: The proportion of participants stopping smoking for 24 hours or longer did not differ between arms: 35% (73/209) in the DNA arm versus 36% (78/217) in the non-DNA arm (difference -1%, 95% confidence interval -10% to 8%, P=0.83). The proportion making a quit attempt within the DNA arm did not differ between those who were told they had mutations putting them at increased risk (36%), those told they had none (35%), and those in the non-DNA arm (36%).

Conclusion: Among relatives of patients with Crohn's disease, feedback of DNA based risk assessments does not motivate behaviour change to reduce risk any more or less than standard risk assessment. These findings accord with those across a range of populations and behaviours. They do not support the promulgation of commercial DNA based tests nor the search for gene variants that confer increased risk of common complex diseases on the basis that they effectively motivate health related behaviour change.

Trial registration: Current Controlled Trials ISRCTN21633644.

PubMed Disclaimer

Conflict of interest statement

Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; and no other relationships or activities that could appear to have influenced the submitted work.

Figures

None
Fig 1 Example of information in booklet
None
Fig 2 Flow of participants through study
See this image and copyright information in PMC

Comment in

References

    1. Collins FS, Green ED, Guttmacher AE, Guyer MS. A vision for the future of genomics research. Nature 2003;422:835-47. - PubMed
    1. Gramling R, Nash J, Siren K, Culpepper L. Predictive genetics in primary care: expectations for the motivational impact of genetic testing affects the importance family physicians place on screening for familial cancer risk. Genet Med 2003;5:172-5. - PubMed
    1. Collins F. Has the revolution arrived? Nature 2010;464:674-5. - PMC - PubMed
    1. Chen S, Chaiken S. The heuristic-systematic model in its broader context. In: Chaiken S, Trope Y, eds. Dual process theories in social psychology Guildford Press, 1999:73-96.
    1. Calkins BM. A meta-analysis of the role of smoking in inflammatory bowel disease. Dig Dis Sci 1989;34:1841-54. - PubMed

Publication types

MeSH terms

Substances

Associated data