Long-term changes in sleep and depressive symptoms of smokers in abstinence

Few studies have evaluated the impact of smoking cessation on objective measures of sleep. The present study assessed the long-term effects of tobacco smoking abstinence on sleep and depression. A total of 15 chronic smokers with Hamilton Rating Scale for Depression (HAM-D) scores of less than 9 were evaluated. Subjects were screened for baseline data when they were smoking chronically. They underwent a 5-week psychological treatment for tobacco smoking, after which their depressive symptoms and sleep architecture were evaluated at 1, 2, 4, 6, 9, and 12 months of abstinence. We report the results of the seven patients who completed 1 year of evaluations and of those patients who achieved only partial abstinence. Polysomnographic recordings were taken, level of depression was measured with the HAM-D, and urinary cotinine levels also were evaluated. HAM-D scores were analyzed with and without sleep items. Nicotine abstinence reduced latency to rapid eye movement (REM) sleep and increased HAM-D scores, suggesting that chronic smokers have depressive symptoms that may be controlled by nicotine administration.