Should reducing smoking to quit be used as an alternative to abrupt quitting by smoking cessation services? Results from a randomised controlled non-inferiority trial Dr. Nicola Lindson-Hawley (UKCTCS)
09.30, Wednesday 10 July. Millennium Lounge, level 5
The problem
The approach to quitting smoking advised by many smoking cessation services is to stop abruptly. However, evidence suggests that some smokers would prefer to quit by reducing the amount they smoke before their quit day. Therefore, it may be useful to offer smoking reduction alongside abrupt quitting, to increase the number of smokers accessing treatment services. It is important to first ascertain whether reduction is as successful a quitting method. The few studies which have compared the approaches typically had small sample sizes and only measured the superiority of the effect.
The approach
The Rapid Reduction Trial (RRT) aimed to establish whether the efficacy of reducing smoking to quit is non-inferior to that of abrupt quitting. RRT is a randomised controlled, non- inferiority trial (N=697), with a non-inferiority margin of 9.5% difference in efficacy between arms. Patients wishing to quit smoking were recruited through their GP practice, and randomised to quit abruptly after a two week period or to reduce their smoking by 75% over a two week period, before quitting completely. Both arms received weekly face-to-face behavioural support, and used nicotine replacement therapy in the run up to, and following their quit day. The primary outcome of the trial was abstinence at four weeks, calculated using intention to treat analysis. Secondary outcomes included abstinence six months post-quit.
Findings
At baseline the median age of participants was 49 years (IQR= 17), median cigarettes per day= 20 (IQR= 10), median Fagerstrom Test for Nicotine Dependence =6 (IQR= 3) and 50.2% of participants were male. 49.0% of participants quitting abruptly were CO validated prolonged abstinent at 4 week follow-up, compared with 39.2% of participants who reduced their smoking to quit; producing a risk ratio of 0.80 (95% CI= 0.67, 0.95). Abrupt cessation was significantly more effective than reducing smoking to quit (p=0.01) but the difference was not significantly greater than our pre-specified non-inferiority margin. Analysis of drop-out rates suggest that more reduction participants dropped out pre-quit, and of those participants who made a quit attempt abstinence rates did not differ between arms.
Consequences
In line with population level data, this trial found that quitting smoking by gradual reduction was less effective than quitting abruptly, but the difference was relatively modest and so quitting gradually may be a suitable option for smokers who otherwise would not try to quit at all. The extra people that it may bring into services could still lead to an increase in overall quit rates. However, work is needed to investigate whether offering gradual cessation would cause more smokers to seek help to quit. Ways to reduce the pre-quit drop-out rate of smoking reduction interventions should also be investigated with an aim to maximise quit rates.
The approach to quitting smoking advised by many smoking cessation services is to stop abruptly. However, evidence suggests that some smokers would prefer to quit by reducing the amount they smoke before their quit day. Therefore, it may be useful to offer smoking reduction alongside abrupt quitting, to increase the number of smokers accessing treatment services. It is important to first ascertain whether reduction is as successful a quitting method. The few studies which have compared the approaches typically had small sample sizes and only measured the superiority of the effect.
The approach
The Rapid Reduction Trial (RRT) aimed to establish whether the efficacy of reducing smoking to quit is non-inferior to that of abrupt quitting. RRT is a randomised controlled, non- inferiority trial (N=697), with a non-inferiority margin of 9.5% difference in efficacy between arms. Patients wishing to quit smoking were recruited through their GP practice, and randomised to quit abruptly after a two week period or to reduce their smoking by 75% over a two week period, before quitting completely. Both arms received weekly face-to-face behavioural support, and used nicotine replacement therapy in the run up to, and following their quit day. The primary outcome of the trial was abstinence at four weeks, calculated using intention to treat analysis. Secondary outcomes included abstinence six months post-quit.
Findings
At baseline the median age of participants was 49 years (IQR= 17), median cigarettes per day= 20 (IQR= 10), median Fagerstrom Test for Nicotine Dependence =6 (IQR= 3) and 50.2% of participants were male. 49.0% of participants quitting abruptly were CO validated prolonged abstinent at 4 week follow-up, compared with 39.2% of participants who reduced their smoking to quit; producing a risk ratio of 0.80 (95% CI= 0.67, 0.95). Abrupt cessation was significantly more effective than reducing smoking to quit (p=0.01) but the difference was not significantly greater than our pre-specified non-inferiority margin. Analysis of drop-out rates suggest that more reduction participants dropped out pre-quit, and of those participants who made a quit attempt abstinence rates did not differ between arms.
Consequences
In line with population level data, this trial found that quitting smoking by gradual reduction was less effective than quitting abruptly, but the difference was relatively modest and so quitting gradually may be a suitable option for smokers who otherwise would not try to quit at all. The extra people that it may bring into services could still lead to an increase in overall quit rates. However, work is needed to investigate whether offering gradual cessation would cause more smokers to seek help to quit. Ways to reduce the pre-quit drop-out rate of smoking reduction interventions should also be investigated with an aim to maximise quit rates.