Background
Major depression and other depressive conditions are common in people with cancer. However, because of the overlap between medical and psychiatric symptoms, these conditions are not easily detectable in clinical practice. Moreover, it is particularly challenging to distinguish between pathological and normal reactions to such a severe illness. It has been widely recognized that depressive symptoms, even in subthreshold manifestations, have a negative impact in terms of quality of life, compliance with anticancer treatment, suicide risk, and likely even the mortality rate for the cancer itself. Thus, providing better interventions to people with cancer and depressive symptoms is an important goal. There is still uncertainty on the true efficacy of antidepressants for the treatment of depression in people with cancer, as data from randomized controlled trials (RCTs) in such a population are few and often contrasting. For these reasons, a systematic review was warranted.
Objective
The aim of the systematic review1 was to assess the efficacy and acceptability of antidepressants for treating depressive symptoms in adults (>=18 years old) with cancer (any site and stage).
Intervention/Methods
The review included RCTs allocating adults (>=18 years old) with any primary diagnosis of cancer and depression (including major depressive disorder, adjustment disorder, dysthymic disorder, or depressive symptoms in the absence of a formal diagnosis) comparing antidepressants versus placebo, or antidepressants versus other antidepressants. Studies that compared antidepressants with another type of psychopharmacological agent were excluded. Nine studies (861 participants) were reviewed. Seven of these studies contributed to the meta-analysis for the primary outcome, that is, the acute-phase treatment response (between 6 and 12 weeks). Four of these compared antidepressants and placebo, 2 studies compared 2 antidepressants, and one 3-arm study compared 2 antidepressants and a placebo arm.
The quality of the evidence was very low because of poor reporting, imprecision arising from small sample sizes, and inconsistency due to statistical or clinical heterogeneity.
Results
* There was no statistically significant difference between antidepressants as a class and placebo, with a standardized mean difference of -0.45 (95% confidence interval, -1.01 to 0.11; 5 studies, 266 participants).
* There was no statistically significant difference between selective serotonin reuptake inhibitors and tricyclic antidepressants as classes, with a standardized mean difference of -0.08 (95% confidence interval, -0.34 to 0.18; 3 RCTs, 237 participants).
* The authors downgraded the quality of the evidence because the included studies were at an unclear or high risk of bias.
Conclusions
Despite the impact of depression on people with cancer, available studies were very few and of low quality. This review found very low-quality evidence for the effects of these drugs compared with placebo. There is need for larger and pragmatic randomized trials on this topic, including antidepressants that are already largely used in clinical practice (eg, mirtazapine).
Implications for Practice
On the basis of these results, implications for practice can only be rather generic and provisional. Above all, an accurate evaluation of depressive experiences should be routinely performed in cancer patients. The choice of prescribing an antidepressant should be evaluated on an individual basis. Data from studies on the general population of individuals with major depression may provide general indications on antidepressants' efficacy and tolerability profiles. Finally, it is noteworthy that data from medically ill people suggest a positive safety profile of selective serotonin reuptake inhibitors. [The full review report, including references, can be accessed at http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD011006.pub2/citedby].
Lei Cheng, MSc
Nursing School of Fudan University
Shanghai People's Republic of China
A Member of the Cochrane Nursing Care Field (CNCF)
Reference