Risk Factors for Recurrence of Depression

Depression is a common mental health disorder that negatively affects daily functioning and quality of life. Unfortunately, depression is often a recurrent disorder. Current treatment guidelines are based on clinical features of the disease, but new evidence points to sociodemographic and psychosocial characteristics that influence the severity and prognosis of depression. Specifically, a study published in the Canadian Medical Association Journal highlights smoking and a feeling of lack of control over one’s life as significant predictors of a negative long-term prognosis of depression.

The population-based survey evaluated nearly 600 people aged 16 or older who participated in a national health survey. The national survey included more than 17,000 participants, and the subjects in this evaluation were those who had reported a major depressive episode in the first year of the survey. The participants were followed for six years. More than half (64.5%) of the participants were women, and, at baseline, the average age of the group was approximately 39 years. Most of the participants were white (91.7%) and earned a middle to high income (81.5%). Nearly two-thirds had achieved greater than a high school education.

Over the follow-up period, slightly more than half (55.3%) of the survey population experienced repeated episodes of depression. The authors evaluated numerous physical, emotional, psychological, social, and demographic characteristics of the participants to examine their association with depressive episodes. Daily smoking and low mastery (feeling that life circumstances are beyond one’s control) were significant predictors of recurrent depression. A history of depression, which is already a well-established risk factor for future episodes of depression, was also significantly related to recurrent depressive episodes in this study. The association between risk factors and depressive episodes varied with the severity of depression.

Due to the nature of the study and the small sample size, the direction of effect and causal mechanisms are unclear. However, interventions that promote smoking cessation and increase mastery may provide positive mental health outcomes. Smoking cessation has obvious health benefits, and high levels of mastery are linked to regular physical activity, a healthy diet, decreased metabolic risk factors, and a decreased risk of death from cardiovascular factors. In fact, high levels of mastery at baseline were protective against recurrent episodes of depression in this population.

Smoking and mastery are simple and straightforward to assess in routine clinical practice. According to the authors of the current study, these novel prognostic factors may offer new avenues for treatment of depression and prevention of recurrent depressive episodes.


Colman I, Naicker K, Zeng Y, Ataullahjan A, Senthilselvan A, & Patten SB (2011). Predictors of long-term prognosis of depression. CMAJ : Canadian Medical Association journal = journal de l’Association medicale canadienne, 183 (17), 1969-76 PMID: 22025655

Howland RH, Wilson MG, Kornstein SG, Clayton AH, Trivedi MH, Wohlreich MM, & Fava M (2008). Factors predicting reduced antidepressant response: experience with the SNRI duloxetine in patients with major depression. Annals of clinical psychiatry : official journal of the American Academy of Clinical Psychiatrists, 20 (4), 209-18 PMID: 19034753

Katon W, Unützer J, & Russo J (2010). Major depression: the importance of clinical characteristics and treatment response to prognosis. Depression and anxiety, 27 (1), 19-26 PMID: 19798766

Image via stavklem / Shutterstock.

  • Great article. Interesting that smoking plays such a crucial role in schizophrenia and depression.

  • Richard Kensinger, MSW

    The lifetime prevalence of CD over the world is about 1 in 7. CD accounts for about 1 in 2 suicides when it is undetected or undertreated. Additional risk factors are: males are 4 X more prone to complete it; high levels of worthlessness, hopelessness, & helplessness (suicidal triad); alcohol increses the liklihood X 30; and easy access to weapons.

    Recurrence rates are as follows: 50% after 1 episode, 70% after 2, and 90%+ after 3. The natural duration of CD runs from 7 ~ 11 months. Antideressant therapy + pschotherapy is quite efficacious in treating it. ECT are a life-saver for those who don’t respond to above.

    And the sense of mastery is a combiation of important psychosocial mediating factors that either protect or increase risk to stress. One is locus of control, another is self-efficacy, and its 2 components are confidence & competence. There are at least 5 others.

    I’ve not encountered the nicotine connection to CD.


  • See “Depression and nicotine: Preclinical and clinical evidence for common mechanisms.”
    [Current Psychiatry Reports]

  • Smoking is one of several factors that deplete folate levels, and folate is required as a precursor for BH4. BH4 is required for Triptophan and Tyrosine. These two elements are required for the production of Seritonin, Norepeipherine, and Dopamine. So the theory goes that smoking, along with other factors (see Deplin website for some of the listed factors) may hinder the entire cycle of required neurotransmitters. I have also included articles to further explain L-methylfolate.



  • onergk69

    The 2 neurotransmitters most commonly linked to CD are Norepinephrine & Serotonin. Some of the antidepressants target NE alone, Sert. alone; and some of newest generation, impact both at the same time. To my clinical knowledge, independent investigations show no superiority to any of the AD’s. They do vary in re: to side-effect & adverse event profiles.


  • Using tobacco is one of several aspects that lessen vitamin b folic acid stages, and vitamin b folic acid is necessary as a forerunner for BH4. BH4 is necessary for Triptophan and Tyrosine. These two components are necessary for the of Serotonin, Ionospheric, and Dopamine. So the concept goes that smoking, along with other aspects (see Deplin web page for some of the detailed factors) may restrict the whole pattern of necessary chemicals. I have also provided content to further describe L-methylated. thanks

Jennifer Gibson, PharmD

Jennifer Gibson, PharmD, is a practicing clinical pharmacist and medical writer/editor with experience in researching and preparing scientific publications, developing public relations materials, creating educational resources and presentations, and editing technical manuscripts. She is the owner of Excalibur Scientific, LLC.

See All Posts By The Author

Do not miss out ever again. Subscribe to get our newsletter delivered to your inbox a few times a month.