Conditions of sleep restoration after smoking cessation: A systematic review

Previous studies have highlighted the prevalence of disordered sleep in smokers, with subjective sleep complaints and alterations of sleep architecture, including a reduction in slow-wave sleep (SWS). These findings raise questions regarding the impact of smoking cessation and withdrawal on sleep. This review aims to assess the impact of smoking cessation on sleep by taking into account objective and subjective methods of assessment. The selected articles compared both participants' sleep before and after smoking cessation, and the sleep characteristics of patients who had relapsed compared to those who had maintained abstinence. The selected studies presented results for patients who did not receive any cessation treatment, or who received either medication-based or psychotherapeutic treatments. In patients undergoing smoking cessation without NRT, the N1 stage was reduced in those maintaining abstinence for 6 months, while rapid eye movement (REM) sleep was reduced only in those who relapsed. No significant difference in SWS was observed between patients who maintained abstinence and those who relapsed. Regarding the use of NRT, one study observed that long-term nicotine patches, compared to short-acting patches, were associated with an increase in SWS. Despite heterogeneous results, sleep alterations appear to persist for the first few weeks of withdrawal and predict relapses. Finally, although limited, there seems to be a restoration of sleep for patients using NRT.