Mindfulness-based cognitive therapy: an efficacious community-based group intervention for depression and anxiety in a sample of cancer patients

Optimal care of cancer patients incorporates effective psychosocial support.1 There is considerable evidence suggesting that people affected by cancer suffer from substantial long-term psychological distress.2,3 Indeed, the prevalence of symptoms of distress in cancer patients has been estimated to be in the 35%–45% range,4,5 and is now considered the sixth vital sign.6 As survival rates continue to improve, there is an increased need to provide effective support and intervention for people affected by cancer at all stages of the cancer journey.6

Group interventions offer many advantages over individual interventions, including improved cost-effectiveness along with the benefit of social and peer support.7 They have also been shown to be as efficacious as individual interventions.8 Mindfulness-based interventions are contemporary examples of group interventions that are demonstrating their clinical efficacy and receiving burgeoning attention in the literature.9

Mindfulness, defined as bringing one’s attention to the experiences occurring in the present moment, in a non-judgemental or accepting way, consists of a number of facets including non-reactivity, observational awareness, acting with awareness and concentration, describing, and a non-judgemental attitude towards an experience.10

Originally developed as a program for people experiencing chronic pain and stress-related disorders, mindfulness-based stress reduction (MBSR)11 is now the most frequently cited intervention with demonstrable effects for a variety of chronic conditions including cancer.9,12

Mindfulness-based cognitive therapy (MBCT),13 as an efficacious treatment to prevent relapse in chronically depressive patients, is based on the MBSR program. MBCT integrates elements of cognitive therapy that promote a “decentred” relationship with one’s thoughts. Research supports the use of MBSR in many applications,14,15 but, to date, less is known about the efficacy of MBCT in the cancer setting.

In this article, we report on the evaluation of an MBCT program conducted at Cancer Council South Australia (CCSA) between 30 September and 18 November 2008 and between 20 February and 10 April 2009 (results from both groups were combined). Specifically, we seek to address the impact of such a program on depression and anxiety in people affected by cancer, and this report incorporates consumer feedback.

Participants were recruited for the study from 20 June 2008 to 12 February 2009 through calls to the CCSA Helpline. Participants were: (i) informed of the program after contacting the CCSA Helpline for information and/or support; and (ii) referred to the CCSA Helpline for further information by means of flyers placed in primary care facilities or distributed through cancer support group leaders in the Adelaide metropolitan region. Participation was open to people with a history of cancer and carers of people with cancer.

The MBCT program facilitator completed a screening interview by telephone to exclude people with severe psychiatric disorders and substance misuse — potential participants were asked if they were currently receiving treatment for a psychological disorder and further questions probed for information concerning the use of substances. Participants were sent an information sheet, consent form and questionnaire, which they submitted in person before commencing the first MBCT session.

Ethics approval was granted by Cancer Council South Australia’s Human Research Ethics Committee.

Demographic characteristics recorded included age, sex, highest level of education, marital status, type of cancer and time since diagnosis (where applicable).

Depression and state anxiety (a transitory emotional state that is characterised by subjective, consciously perceived feelings of tension and apprehension and heightened autonomic nervous system activity16) levels were assessed using the Beck Depression Inventory — second edition (BDI-II)17 and Form Y-1 of the State–Trait Anxiety Inventory (STAI).16 Both measures have demonstrated reliability and validity in clinical and research settings.16-19 Clinical ranges for the BDI-II are: 0–13, minimal depression; 14–19, mild depression; 20–28, moderate depression; and 29–63, severe depression.17 Clinical ranges for the STAI are: 20–39, non-clinical anxiety; and 40–80, clinical anxiety.16

Mindfulness was measured using the short form of the Freiburg Mindfulness Inventory (FMI).20

Consumer-centred evaluation was achieved through open-ended questions that sought feedback about participants’ perceptions of the program (eg, positive and/or negative effects, relevance to the cancer experience, ease with which mindfulness was incorporated into daily living, barriers to implementation).

The MBCT program comprised eight weekly 2-hour sessions:

• stepping out of automatic pilot;

• dealing with barriers;

• mindfulness of one’s breath;

• staying present;

• acceptance, holding, allowing, letting be;

• thoughts are not facts;

• how can I best take care of myself?; and

• using what you have learned to deal with future mood.14

Participants attended one of two identical MBCT programs conducted at CCSA and facilitated by an experienced counsellor trained in MBCT. An optional 3-hour follow-up session was conducted 6 weeks after the end of each program to reinforce principles underpinning mindfulness practice.

Participants were provided with homework comprising notes and compact discs containing instructions to complete:

• body scan and mindfulness of breath;

• mindful movement and extended sitting meditation; and

• mountain and lake meditations (guided visualisations which use the image of mountain if seated, or lake if lying down, to explore the ability to remain steady in spite of the changing “weather” or seasons of life11).

Participants were encouraged to practise 45 minutes of mindfulness-based exercise 6 out of 7 days per week in order to facilitate integration of mindfulness principles into their lives and to record the time that they spent on these exercises in the homework diary provided.

A pretreatment questionnaire, comprising all key study variables, was posted to participants and had to be completed and handed to the facilitator before commencement of the first session. At two time points after completion of the intervention (1 week and 3 months), participants were sent a questionnaire that covered (i) all key study variables and (ii) consumer-centred evaluation. To maximise response rate, the MBCT facilitator followed up with participants who had not yet returned their questionnaire.

The two MBCT programs were attended by 25 participants (13 in the first program and 12 in the second). Six participants attending the first program and eight attending the second also attended the optional 3-hour follow-up session 6 weeks later. Of the 25 participants who commenced the program, 22 were women and three were men, and their ages ranged from 34 to 69 years (mean age, 51.36 years; SD, 10.26). Three of these withdrew before completion, and one did not complete the postintervention and 3-month follow-up questionnaires. Thus, the following analyses include data for 21 participants (18 women, three men), aged 34 to 69 years (mean age, 52.0 years; SD, 10.2). These participants included 16 with a history of cancer and five carers. Eight of those with cancer had breast cancer. Other participants with cancer reported the following cancer types: glioblastoma multiforme; adenoid cystic carcinoma; acute myeloid leukaemia; lymphoma; liver cancer; bladder cancer; ovarian cancer; and prostate cancer. Time since diagnosis ranged from approximately 3 months to 120 months (mean, 30.88 months; SD, 32.09).

Of our 21 participants, 11 had completed secondary school and 10 had completed some form of tertiary education. Seventeen participants were currently married or in a de-facto relationship, two participants were single and two were either separated or divorced. One participant self-identified as having depression and was currently seeing a psychiatrist.

Preliminary analyses revealed no significant differences between the baseline scores of patients and carers on our outcome measures (t = < 1 for the BDI, STAI and FMI), so data from both MBCT programs were combined for further analyses.

Three participants had extensive missing data at only one time point (one at postintervention and two at 3-month follow-up). Such missing data were excluded from all relevant analyses.

Our findings indicate that the MBCT program had a positive and sustained effect in reducing self-reported levels of depression and anxiety. Importantly, these benefits were linked with increases in mindfulness across each stage of assessment.

Depression and anxiety levels were significantly lower after the intervention, and these low levels were sustained 3 months after completing the MBCT program. These results are consistent with previous research applying MBCT to depression,22 and support its efficacy in people affected by cancer. Furthermore, reliable change indices indicated that MBCT is effective at reducing all levels of anxiety; however, as an efficacious intervention for depression, it may be more valuable for people with moderate to severe levels of depression. Although, feedback from participants indicated that even those with lower levels of distress found participation in the program invaluable.

There was a slight rebound in anxiety levels at the 3-month assessment. Reliable change indices identified two participants whose anxiety levels had increased from baseline; further investigation of demographic data did not reveal a common characteristic between these two participants. Reasons for this adverse outcome are unknown and so may be unrelated to the program. Responses to the consumer-centred evaluation underscored the value of the follow-up session and future applications may include additional or ongoing “booster” sessions.

In line with previous qualitative research,22 participants perceived MBCT as beneficial. Feedback revealed that it was the inclusion of principles of mindfulness in one’s life that provided the most benefit. However, not all components of the course were without criticism (eg, its emphasis on depression), suggesting that some participants do not relate to the term “depression”.

The group setting was considered important. Research suggests that people affected by cancer prefer to discuss issues with peers rather than with a general practitioner or psychologist.23 Therefore, there still remains the challenge of determining whether it is the adoption of mindfulness practice or the peer support gained during the delivery of the MBCT program that contributes most to therapeutic outcome.

Moreover, there is still debate about how best to define and measure the concept of mindfulness.10,20 Although research supports the psychometric properties of available scales,19 it is not yet clear to what extent these measures are capturing the cognitive elements proposed in the MBCT program. Thus, the extent to which MBCT is superior to MBSR is as yet unknown.

Our study has a number of limitations. Firstly, it lacked a control group. Nevertheless, the systematic variation in mindfulness scores alongside changes in distress levels suggests that engagement with mindfulness practice leads to improved therapeutic outcome. Secondly, few carers participated in this study so the results may not be generalisable to carers. Similarly, the study sample was recruited essentially by opportunity, and thus results may not be applicable to all cancer types or stages in the cancer journey. Finally, further research should include provision for recording the amount of homework performed by participants, as ongoing practice is featured as a central requirement in the delivery of MBCT interventions.

Overall, this study provides preliminary support for the use of MBCT as an effective psychosocial intervention for people affected by cancer.