It was estimated that nicotine affects the human’s reward system. As a result, smoking cessation might lead to depression and other mental disorder. However, a meta-analysis of existed researches demonstrated that smoking quitting does not lead to depression. On the contrary, cigarette cessation can improve the mental health state after three weeks after quitting. Possible biological mechanisms of depression appearance and mental health improvement are described.
Cigarette smoking is a dangerous habit that leads to the early death of smokers. According to Taylor et al. (2014), smoking is a reason for five million deaths a year (p. 1151). Besides, it is widely known that people spend an enormous amount of money on cigarettes. Therefore, a lot of people have the intention to quit smoking. However, it was stated that the cessation is quite difficult to perform due to smokers’ psychological addiction. Smoking quitting frequently leads to depression, which could be a reason for the relapse (Cook et al., 2015).
On the other hand, some scientists believe that smoking cessation leads to mental health improvement (Taylor et al., 2014). Therefore, it is highly important to estimate the connection between smoking cessation and depression based on the Patient Health Questionnaire-9 (PHQ-9) investigation results.
Possible Reasons for Depression after Smoking Cessation
The connection between tobacco use and mental health is not entirely clear. It was postulated that after quitting, people started to feel anxiety, irritability, and depression (Taylor et al., 2014). Possible reason for it is the following: nicotine is a source of pleasure for smokers. Moreover, it was proved that this substance affects the reward system and the ability to experience pleasure from other stimuli (Thomas et al., 2013).
Therefore, the tobacco withdrawal syndrome could be a possible reason for anhedonia and depression because nicotine deprivation can affect a capacity to experience pleasure and diminish reward value, which leads to the inability to enjoy non-cigarette related activities and, consequently, to depression (Cook et al., 2015). Another possible reason for depression development is that smokers might use tobacco as antidepressants to overcome already existing depression. Thus, after quitting, symptoms of it become more evident (Thomas et al., 2013).
Review of Existed Studies
Taylor et al. (2014) provided a systematic review and meta-analysis of existed researches dedicated to a mental state of people immediately before and six weeks after quitting. Overall, 26 studies were included in the meta-analysis. In these studies, data about depression level and other mental disorders were obtained from different questionnaires, including PHQ-9. According to the results of the meta-analysis, smoking cessation is associated with mental health improvement. Participants of the investigations demonstrated a lower level of depression symptoms. Results were similar for both the general population and clinical patients.
A possible mechanism of depression symptoms’ decrease is the following: nicotinic pathway appeared in the brains of smokers. This pathway results in the depression mood and anxiety short after an act of smoking. Approximately after three weeks after cessation, nicotinic pathway disappeared, and neurological functions of a former smoker become the same as the functions of a non-smoker (Taylor et al., 2014).
According to the widely accepted point of view, smoking quitting might lead to mental disorders and depression appearance due to the biological mechanisms of the nicotine action. However, other researches demonstrated that shortly after cessation, all negative effects are terminated. Therefore, it could be concluded that smoking cessation not necessarily leads to depression appearance. Moreover, it was estimated that smoking quitting might be a reason for mental health improvement. The positive effect of stopping appeared approximately after three weeks of cessation.
Cook, J. W., Piper, M. E., Leventhal, A. M., Schlam, T. R., Fiore, M. C., & Baker, T. B. (2015). Anhedonia as a component of the tobacco withdrawal syndrome. Journal of Abnormal Psychology, 124(1), 215-225. Web.
Taylor, G., McNeill, A., Girling, A., Farley, A., Lindson-Hawley, N., & Aveyard, P. (2014). Change in mental health after smoking cessation: Systematic review and meta-analysis. British Medical Journal, 348, 1151-1173. Web.
Thomas, K. H., Martin, R. M., Davies, N. M., Metcalfe, C., Windmeijer, F., & Gunnell, D. (2013). Smoking cessation treatment and risk of depression, suicide, and self harm in the clinical practice research datalink: Prospective cohort study. British Medical Journal, 347, 5704-5713. Web.