Interventions to Promote Resilience in Cancer Patients
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Background: Resilience is the ability to maintain or rapidly regain mental health during or after stressful life experiences. Cancer is a major risk factor for stress-associated mental illness. In this review, we attempt to identify effective resilience-promoting interventions in adults with cancer.
Methods: The analysis was restricted to randomized, controlled trials of resilience-promoting interventions in adults with cancer in which training was provided for at least one psychosocial resilience factor. A selective search, with systematic components, for relevant publications was carried out in the PubMed and CENTRAL databases. Effect sizes (Hedges’ g) were calculated wherever a fully reported dataset for resilience or post-traumatic growth was available.
Results: Twenty-two trials with a total of 2,912 patients were included in the analysis; the intervention was provided in an individual setting in five trials and in group format in 17. Beneficial effects on resilience and post-traumatic growth, some of them large, were observed in patients who were acutely ill with cancer and after interventions that were provided in more than 12 sessions. The effect size ranged from g = 0.33 to g = 1.45. Largely beneficial effects were achieved by interventions based on the concepts of positive psychology, supportive–expressive group therapy, behavioral therapy, or mindfulness, with considerable variation in individual effect sizes.
Conclusion: Interventions that promote resilience should be made available to interested and motivated cancer patients. These interventions should be provided, in parallel with somatic treatment, as soon as the diagnosis is made and should extend over more than 12 sessions whenever possible.
In Germany, around four million people are currently living with the diagnosis of cancer (1). Having been diagnosed with cancer, more than one third of patients develop symptoms of depression, an adjustment disorder, or an anxiety disorder in the course of the next 5 years (2). Besides the loss of quality of life, these stress-related mental health problems have a negative impact on the prognosis of the oncological disease, as they lead to poorer adherence to the planned treatment and other unfavorable effects (3, 4).
One way of promoting health in this risk group is to strengthen resilience. Resilience can be defined as the maintenance or fast recovery of mental health during or after exposure to significant stressors (5). Resilience is regarded as the result of adaptation to stressors and increasingly understood as a dynamic (learning) process that can be trained (6–8). Resilience as the outcome of such adaptation is presumably influenced to some extent by multiple resilience factors, such as self-esteem, realistic optimism, or cognitive flexibility; thus, strengthening these factors can have a positive effect on the development and preservation of resilience (9). During this process, people change due to one or more of the following (5):
- New attitudes and views
- Newly acquired strengths and competencies
- Partial immunization to the effects of future stressors
- Epigenetic modifications.
A positive correlation (r = 0.43, 95% confidence interval [0.39; 0.48], p <0.001) between resilience (measured using the Wagnild and Young resilience scale ) and mental health in the somatically ill has recently been demonstrated in a meta-analysis (11).
Posttraumatic growth is defined as positive personal development resulting from critical or traumatic exposure to a stressor (12). This growth is explained not by the exposure itself, but rather by the subsequent process of coming to terms with the stressor and coping with the problematic situation (12). Especially in cancer patients, it is assumed that the frequently observed post-traumatic growth results from coping with the disease (13).
Resilience and post-traumatic growth are closely related concepts, above all in terms of reconfiguration (14), because numerous resilience factors are also associated with post-traumatic growth (15). While resilience involves a return to the baseline level, post-traumatic growth involves a positive change going beyond the earlier level of psychological functioning (15). In this paper, resilience and post-traumatic growth are treated as equivalent.
Resilience-enhancing interventions aim at promoting individual resilience in the context of a significant stressor. Thus, they can be implemented in cancer patients immediately after acute stressor exposure in terms of the initial cancer diagnosis or the discovery of a recurrence, but also during (chronic) stressor exposure over the course of the disease and with treatment (16–19). As they seek to strengthen one or more resilience factors, i.e., internal or external psychosocial resources, resilience interventions are generally resource-oriented. These factors include, for example, problem-solving skills, self-efficacy, optimism, or acceptance of negative situations and emotions (20).
To date, the effect of resilience-enhancing interventions on mental health and wellbeing has been evaluated in two systematic reviews and three meta-analyses, none of which focused specifically on cancer patients (21–25). The aim of this paper is to provide a narrative review of resilience-enhancing interventions in adult cancer patients. The two key questions evaluated were:
- To what extent do the following potential moderators influence the effects on resilience/post-traumatic growth:
– the individual cancer disease
– mental disorder comorbidities
– the theoretical foundation
– the dose of the interventions?
- How stable are the effects of the interventions over time?
A detailed description of the methods used is provided in the eMethods. Studies meeting the criteria listed in Table 1 were included in this review. We carried out a selective search of the literature with systematic components in the PubMed database and the Cochrane Library (CENTRAL) for publications between January 1990 and May 2018. Study selection and data extraction was performed by one assessor (PL).
Selection of studies
The initial search of the literature identified 1178 studies. Of these, 22 studies with i = 22 reported samples met the inclusion criteria and were thus included in this narrative review (Figure). In 15 of the 22 studies, a quantitative analysis with calculation of effect sizes could be performed, including 5 studies with several follow-up measurements after the end of the interventions.
An overview of the included studies is provided in Table 2 and in eTables 1 to 5. Altogether, studies from 12 countries with 2912 patients, published between 2010 and 2018, were taken into account. The following types of cancer were treated:
- Breast cancer (11×)
- Colorectal cancer (3×)
- Gastric cancer (1×)
- Prostate cancer (1×)
- Mixed forms of cancer (6×).
Twelve studies included only female patients, 1 study only male patients, and the remaining 9 studies both male and female patients. While 2 studies included patients with mental disorders, 7 studies excluded patients with any kind of mental disorder. In the remaining 13 studies, only specific mental illnesses, such as psychotic or affective disorders, were listed among the exclusion criteria. Since some studies did not report age and gender data, it was not possible to calculate mean age and gender distribution (eTables 1 and 4).
In 20 studies, the interventions were provided face-to-face, in 1 study over the phone, and in 1 study online. Group interventions were used in 17 studies and individual interventions in 5 studies. Seventeen studies used a waiting-list control group or treatment as usual, 3 studies an active control group and 1 study an active control group as well as a comparison group with treatment as usual. One study provided no detailed description of the control group. No subgroup analysis was performed for these groups.
As the outcome measure, 14 studies used the Posttraumatic Growth Inventory (PTGI) (26) and 8 studies employed various forms of the Connor–Davidson Resilience Scale (CD-RISC). The original 25-item version of the CD-RISC (27) was used in 4 of these studies, while the version reduced to 10 items by Campbell-Sills and Stein (28) was used in 3 studies. One study used the two-item version (29).
In seven studies, the sample size was less than 50 patients; in six studies, 50 to 99 patients; in four studies, 100 to 149 patients; and in five studies, 150 or more patients. Among the samples with fewer than 50 patients, one of five studies demonstrated a significantly positive effect after the end of the intervention (Hedges’ g = 1.27); among the samples with 100 to 149 patients, one of three studies (g = 0.69); and among the samples with 150 or more patients, three of four studies (g = 0.33–0.88). Looking at all studies included in this review, the study by O’Brien (2017), with a sample size of less than 50 patients, was the only study to report a significantly negative effect (g = –0.97) (30)
Treatment period/stage of the disease
Patients with “chronic cancer” were investigated in 8 studies, patients of the category “chronic cancer, advanced stage” in 3 studies, and patients meeting the criteria for “acute cancer“ in 10 studies. One study with a very heterogeneous patient population could not be allocated to any of these groups. One of four studies in the “chronic cancer” group found a significantly positive effect on resilience (g = 0.33). In one study of cancer survivors with advanced disease, a significantly positive effect was found (g = 0.66). In the group with acute cancer patients, the effect sizes found in four of nine studies were in the significantly positive range (g = 0.88–1.78). When only the studies with more than 50 analyzed acute cancer patients were considered, all calculated effect sizes were positive, and in three of the five studies they were in the significantly positive range (g = 0.88–1.78).
Five studies evaluated short interventions (<8 sessions and <12 h), 13 investigated medium-length interventions (≥ 8 <12 sessions or ≥ 12 <24 h), and 3 analyzed long interventions (≥ 12 sessions or ≥ 24 h) for resilience enhancement. One study did not provide information about the number and duration of sessions. While a significantly positive effect size (g = 1.78) was observed in only one of four studies evaluating short interventions, this was the case in four of nine studies with medium-length interventions (g = 0.41–1.45) and in two studies with long interventions (g = 0.66–0.88). Positive effect sizes were found in seven of eight studies with more than 50 analyzed patients and at least medium-length interventions, and in five of these the results were in the significant range (g = 0.33–1.45).
The theoretical foundation
Six studies evaluated interventions combining cognitive behavioral therapy (CBT) with mindfulness-based psychotherapy. Five studies used mindfulness-based interventions alone. Three resilience training programs were based on the positive psychology approach and two on supportive–expressive group therapy. The other six interventions used a variety of theoretical foundations (e.g., logotherapy, existential analysis, transtheoretical model). The effect sizes of the interventions that were based on a combination of CBT and mindfulness or on mindfulness alone were significantly positive in four of eight studies (g = 0.69–1.78). Two studies using interventions with techniques of positive psychology (g = 0.53–0.88) and two studies using supportive–expressive group therapy (eMethods) found positive effect sizes. One study in each of the two types of theoretical foundation was significantly positive (positive psychology g = 0.88, supportive–expressive group therapy g = 0.9).
Time of measurement
With regard to the time of measurement, we differentiated between data obtained immediately (n = 10), more than 4 weeks (n = 2), more than 3 months (n = 5), more than 6 months (n = 4), or more than 1 year (n = 1) after the intervention. Immediately after the intervention, positive effect sizes for resilience were found in 5 out of 10 measurements (g = 0.66–1.45). In four of the five studies with several follow-up measurements, the effect sizes at the later measurement times were within the significantly positive range and remained stable or continued to increase (g = 0.78–2.03).
This article is the first narrative review of resilience interventions in cancer patients. Primarily in studies with larger sample sizes, positive effects in terms of increased resilience or post-traumatic growth were achieved. Particularly in the larger studies, the effect sizes were in the significantly positive, small to medium range (Hedges’ g; evaluation of effect size : 0.2 = small, 0.5 = medium, 0.8 = large). Especially the five studies with less than 50 analyzed patients, including one study with a negative effect (30), contributed to the variance of the results in this analysis. These observations are consistent with those reported from previous studies on resilience-enhancing interventions (21–25).
With regard to possible moderators of the effects of resilience interventions on resilience and post-traumatic growth, it was found that, especially in studies on acute cancer patients, the size of the observed effects on resilience and post-traumatic growth was typically large. Consequently, cancer patients can benefit from resilience-enhancing interventions, especially in the period immediately after the diagnosis and in parallel with somatic treatment..
This review found larger effect sizes for resilience and post-traumatic growth with increasing duration of the interventions. This finding suggests that preferably more intense training should be clinically recommended to cancer patients. However, it must be taken into account that some short interventions also achieved good effects (32).
This review was the first to perform a subgroup analysis of different theoretical foundations of resilience-enhancing interventions in patients with cancer. The only systematic review to date that has evaluated resilience interventions in somatically ill patients did not perform such an analysis (23). We found promising results especially for training interventions based on positive psychology, supportive–expressive group therapy, CBT, and mindfulness.
With regard to the duration of the effects on resilience and post-traumatic growth, lasting effects were demonstrated in the follow-up periods. In the studies evaluating several follow-up measurements, the increase in resilience/post-traumatic growth remained largely stable for up to 1 year, or both outcomes improved further. Several studies have already shown that resilience interventions in patient populations at risk for mental illness have positive long-term effects (24, 33). In previous reviews, only limited follow-up data were available for periods more than 3 to 6 months after the end of the intervention. Thus, this review adds new knowledge to the literature on this topic (21–23).
Clear conclusions on the benefits of resilience interventions for cancer patients with or without comorbid mental illness cannot be drawn from this narrative review. Since only two of the studies analyzed included patients with severe mental illness, no subgroup analysis was performed. From a clinical point of view, resilience training appears to be a useful preventive intervention, especially for cancer patients at risk for mental disorder comorbidity. In addition to treatment with psychotherapy and psychiatric medications, cancer patients with severe comorbid mental illness may benefit from resilience training.
Since most interventions were provided face-to-face and in individual sessions, it is difficult to draw concrete conclusions regarding the superiority of a particular delivery type of these interventions from the available studies. However, according to a previous review, face-to-face individual and group sessions achieved better effect sizes—and also better treatment adherence—than online interventions (24).
The majority of studies used groups receiving treatment as usual or waiting-list control groups for comparison; thus, no subgroup analysis was performed. However, the two systematic reviews on resilience interventions that have been published so far indicate that the choice of control group has a considerable impact on the effect size. It was noted, when comparing studies with resilience training versus active control group design with studies with resilience training versus waiting-list control group design, that the effect sizes of the former were at times only half as large (23, 24).
The pronounced heterogeneity of the included studies is a weakness of this review. This can partly be explained by the fact that interventions to enhance resilience and interventions to promote post-traumatic growth were treated equally. Furthermore, there were great differences in how resilience was defined and measured among the various studies included in this review. While the CD-RISC as a quantitative measure of resilience has satisfactory psychometric properties, it does not allow determination of resilience according to the currently prevailing definition as a result or process and it is too strongly correlated with individual resilience factors (21). Hard endpoints, such as the survival rate of cancer patients, were evaluated in only one of the included studies, the results of which were not significant (34).
Since this is a narrative, not a systematic review, study selection and data extraction were carried out by one reviewer only (rather than by two independent reviewers). Furthermore, the risk of bias of the included studies was not evaluated. With regard to the effect sizes and subgroup differences, it has thus to be taken into account that bias may have influenced certain aspects (e.g., selection bias, attrition bias). These limitations could be addressed in a future systematic review on this target population according to international standards.
In addition, for seven studies that met all of the inclusion criteria, it was not possible to calculate effect sizes because missing data could not be obtained despite our attempts to contact the authors.
Despite the limitations mentioned above, the results of this review justify the recommendation that every interested and motivated cancer patient be offered the opportunity to participate in a resilience-enhancing intervention. Especially the period immediately after the diagnosis appears to be conducive to the success of the intervention, in parallel with somatic treatment. This narrative review indicates that longer interventions, with at least 12 therapeutic sessions and a cumulative duration of at least 24 h, achieve the greatest effects on resilience and post-traumatic growth. The currently available evidence does not allow reliable statements to be made on the particular advantages of a specific theoretical foundation or of hard endpoints such as survival. Further research on this topic is therefore needed. Based on the studies that achieved the greatest individual effects on resilience and post-traumatic growth in this review, Table 3 gives an overview of trainable resilience factors and provides examples of exercises for everyday clinical work with cancer patients. Looking forward, there is a need to develop resilience interventions specifically designed for this patient population in a German-language format.
Conflict of interest
The authors declare that no conflict of interest exists.
Received on 24 June 2019, revised version accepted on 30 July 2019
Translated from the original German by Ralf Thoene, MD
Dr. med. Paul Ludolph
Klinik für Psychiatrie und Psychotherapie
Untere Zahlbacher Str. 8
55131 Mainz, Germany
Cite this as:
Ludolph P, Kunzler AM, Stoffers-Winterling J, Helmreich I, Lieb K: Interventions to promote resilience in cancer patients. Dtsch Arztebl Int 2019; 116: 865–72. DOI: 10.3238/arztebl.2019.0865
For eReferences please refer to:
eMethods, eTables, eBox:
Dr. med. Paul Ludolph, Dipl.-Psych. Jutta Stoffers-Winterling, Prof. Dr. med. Klaus Lieb
German Resilience Center (DRZ) Mainz, Mainz, Germany: Dipl.-Psych. Angela M. Kunzler, Dr. phil. Dipl.-Psych. Isabella Helmreich, Prof. Dr. med. Klaus Lieb
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