Effectiveness of postal smoking cessation advice: a randomized controlled trial in young men with reduced FEV1 and asbestos exposure

Abstract

There have been few community-based randomized, controlled intervention trials for cessation in high-risk smokers. In such a trial we evaluated the effects of postal smoking cessation advice in smokers with asbestos exposure and/or reduced forced expiratory volume in one second (FEV1). All men aged 30-45 yrs (n=22,392) living in 34 municipalities in western Norway were invited to a cross-sectional community survey. Information on smoking habits and occupational asbestos exposure were obtained from self-administered questionnaires and measurements of FEV1 were performed with dry-wedge bellow spirometers. Among 16,393 participants we identified a group of 2,610 smokers with previous occupational asbestos exposure and/or adjusted FEV1 in the lowest quartile. A random half (n=1,300) received a mailed personal letter from a respiratory physician with a person-specific health advice to quit smoking and a pamphlet on smoking cessation. The remaining smokers (n=1,310) acted as controls and did not receive any information. Twelve months after the intervention, information on smoking habits was re-examined using a postal questionnaire. Among the respondents (n=2,282), smoking cessation was reported altogether by 13.7% in the intervention group versus 9.9% in the control group (p<0.01). The 1 yr sustained quit rate (no smoking at all during the last year) was 5.6 versus 35% (p<0.05), respectively. Measurements of carbon monoxide in expired air (with < or = 10 parts per million) confirmed self-reported nonsmoking in samples of the two groups. In a community this simple postal smoking cessation advice from a respiratory physician based on person-specific risk factors improved the 1 yr sustained success rate by 60% in identified high-risk smokers.