The impact of depression in patients with cancer
Surely, cancer is a highly impactful life event. When receiving a cancer diagnosis and undergoing treatment for cancer, depression can emerge. In fact, some have estimated that as many as 58% of patients with cancer develop symptoms of depression, with up to 38% fulfilling the criteria for major depressive disorder (MDD) [1,2]. As a result, patients with such symptoms and comorbidity have worse quality of life, worse oncological prognosis, and lower survival rates, when compared to patients without affective symptoms .
How to treat depression in patients with cancer?
Without a doubt, it is fundamental to detect symptoms of depression and find the right treatment as quickly as possible. The two main approaches to treat depression in patients with cancer are psychological interventions and pharmacotherapy . Within psychological interventions, psychotherapy is a more specialised approach and has presented significant efficacy in treating depression in patients with physical illness, including cancer .
How is psychotherapy used as treatment for depression in cancer patients?
Psychotherapy can be defined as “the informed and intentional application of clinical methods and interpersonal stances, derived from established psychological principles, for the purpose of assisting people to modify their behaviours, cognitions, emotions, and/or other personal characteristics, in directions that the participants deem desirable” . Specifically to oncology, several approaches in psychotherapy have proved effective to treat symptoms of depression in cancer patients, such as:
- Acceptance and Commitment Therapy (ACT). ACT is a psychological intervention that uses acceptance and mindfulness, together with commitment and behaviour change strategies, in order to increase psychological flexibility. ACT shows patients ways through which they might understand the need to stop fighting certain aspects of psychological functioning and instead embrace them .
- Cognitive–behaviour therapy (CBT). In CBT, therapists focus on the impact that dysfunctional thoughts have on current behaviour and future functioning. CBT is aimed at evaluating, challenging, and modifying dysfunctional beliefs, through cognitive restructuring. Additionally, this form of psychotherapy emphasizes outside-of-session activities. Therapists exert an active interaction with the patient over therapeutic objectives and topics of discussion, and formulate with them new ways of coping with stressful situations. In addition, besides cognitive restructuring, CBT is composed of strategies such as behavioural activation, social skills training, relaxation, coping skills, and others .
- Existential therapies (ET). Existential psychotherapy is a style of therapy that emphasizes human condition as a whole, considering the premise that human discontent could only be overcome through internal wisdom. Notably, this type of psychotherapy uses a positive approach that applauds human capacities and aspirations, while simultaneously acknowledging human limitations. Moreover, existential psychotherapy shares many similarities with humanistic psychology, experiential psychotherapy, depth psychotherapy and relational psychotherapy .
Indeed, psychotherapy in oncological settings can be implemented individually. For instance, it can be with only the patient and the therapist in the session; in group, where several patients who share a set of similar characteristics receive psychotherapy at the same time in the same session; or in a dyadic dynamic, where the patient attends the session with a significant other. Surely, psychotherapy is applicable irrespective of cancer type, site, or stage and can be provided without the need of both patient(s) and therapist being in the same room, i.e., at a distance. Ultimately, the intervention can be offered in variable numbers of sessions, depending on the needs and the condition of the patient.
What is the efficacy of psychotherapy in the treatment of depression in patients with cancer?
Certainly, scientific research has consistently shown that psychotherapy is effective in the treatment of depression in cancer patients with medium to large effect sizes. While it is clear that patients with cancer and depression benefit from psychotherapy , information regarding different types of psychotherapy in specific groups of patients with cancer is still lacking. For the future, it is fundamental to understand which interventions are more effective for which patients, and under which conditions they should be offered, in order to optimize applicability and efficacy.
Authors: Daniel Silva, Sílvia Almeida, Jaime Grácio, Albino Oliveira-Maia – Champalimaud Foundation
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