The effect of a mindfulness-based intervention in cognitive functions and psychological well-being applied as an early intervention in schizophrenia and high-risk mental state in a Chilean sample: study protocol for a randomized controlled trial

Mindfulness is a research area in psychology that has experienced the greatest development in recent years. These interventions include acceptance and commitment therapy (ACT), mindfulness-based cognitive therapy, mindfulness-based stress reduction therapy, or dialectical behavior therapy. This set of procedures shares the basic notion that, in order to achieve adequate psychological functioning, individuals should change the way in which they relate to their symptoms instead of eliminating them [8]. Recently, these interventions have been grouped under the label of third wave cognitive behavioral therapies [9]. ACT and MBIs are among the third wave therapies used efficiently in psychosis.

Mindfulness can be understood as a specific form of meditation that seeks to increase different psychological functions by means of a synergic effort between attention regulation, self-awareness and emotional regulation, thereby increasing psychological resilience and self-regulation [10]. Mindfulness has been defined as, “Paying attention in a particular way: on purpose, in the present moment, and non-judgmentally” [11]. It has also been conceptualized as a theoretical construction, as a practice and as a psychological process [12]. Training in mindfulness from a Western and academic standpoint has been developed and disseminated through standardized group programs lasting from 8 to 10 weeks and in clinical and health contexts [8, 13].

Such approaches rely on broad empirical support. In fact, recent meta-analyses suggest that mindfulness is an effective intervention for the treatment of several mental health disorders, including depression and anxiety [14, 15]. However, one recent meta-analysis revealed that ACTs and MBIs show promising results in the management of positive and negative symptoms of psychosis [16].

Specifically, the first study of mindfulness in psychosis was conducted in the United Kingdom with patients who suffered stress-induced hallucinations. Patients attended to six mindfulness sessions. The outcomes of this non-controlled study revealed an increase of mindfulness skills in the management of stress-causing thoughts and images. Additionally, the perception regarding the psychological well-being of patients had improved [17]. On the other hand, Chadwick et al. [17] suggested a series of changes to the MBIs when used in psychotic patients in order to ensure the procedure’s feasibility in this population group. Subsequently, Chadwick et al. [18] performed the first controlled study assessing mindfulness skills and overall patient functioning. Both measures improved in the expected direction and showed significant outcomes in intra-group comparisons, but did not do better than the control group. The second controlled clinical trial was conducted in Spain with a small sample of psychotic patients [19], and revealed that, when patients increased their acceptance rates, they also had a less stressing relationship with their thoughts and emotions, in addition to improvements in overall functioning; however, only the first outcome was statistically significant compared to the control group. Another more solid study in terms of the number of participants (N = 98) and the introduction of follow-up measures (18 months) was performed by Lee and Chien [20]. The outcomes of their study revealed that patients showed improved levels of illness insights and overall functioning, and a reduction in symptom severity and in the number and length of hospitalizations. All of these indicators were statistically significant compared to the control group (usual treatment). Recent studies have confirmed the results mentioned above [21, 22]. Other non-controlled studies have proven the feasibility of using mindfulness in patients with psychosis [23‐25].

On the other hand, several qualitative studies have revealed that practicing mindfulness results in a less stressful relationship between patients and their symptoms, with greater flexibility and control over them. This change has a direct impact on the way in which a person relates both to others and to themselves, increasing their confidence and the sense of self-agency. In other words, a person gains an active role in the way they face their symptoms and life, strengthening a self-image that is not only centered around the absence or presence of psychotic symptoms but on their personal resources as the main focus of recovery [26‐28].

Considering all the research in this area, i.e., more than 20 studies including randomized, non-controlled, qualitative, and single case clinical trials [29], two aspects can be pinpointed concerning the use of mindfulness in psychosis. Firstly, that mindfulness reduces the stress associated to psychotic symptoms and thereby promotes patient recovery and, secondly, its implementation in clinical centers is both safe and viable.

Patients will be recruited from six clinical centers from three different cities in Chile; four in Santiago, one in Valdivia, and one in Osorno. Ninety six people are expected to take part in the study, of which 48 will be patients diagnosed with a first episode of schizophrenia (divided into 24 trial and 24 controls) based on the following criteria: patients with a psychotic episode without a prior diagnostic of schizophrenia, patients diagnosed with schizophrenia for the first time, and/or patients who persist with the schizophrenia diagnosis after the first episode. Additionally considered is the participation of 48 patients under a high-risk mental state (divided into 24 trial and 24 controls) who meet the criteria of an Attenuated Psychosis Symptom Syndrome, including delusional beliefs, attenuated hallucinations, and disorganized speech with intact reality testing but of sufficient severity and/or frequency that it is not discounted or ignored [5]. Sample size was estimated considering a previous RCT for people with schizophrenia on both the MBI [20] and a cognitive remediation program [50]. The sample size was calculated by using the statistical program G*Power [51]. The sample required to detect statistically significant differences in the cognitive functioning for a two-tailed test of the proportions with an effect size of 0.80, an alpha of 0.05, and a power of 0.90 is 2 × 39. With an estimated 15–20% drop-out over 3 months, we decided to include 96 persons in the trial, 48 allocated in each intervention arm. The inclusion criteria are (1) patients diagnosed with a first episode of schizophrenia or in high-risk of psychosis, as applicable; (2) aged between 15 and 35 years; and (3) clinical stability defined by medical and psychometric criteria (e.g., PAANS). Exclusion criteria are (1) risk of suicide; (2) severe intellectual disability (mental retardation); (3) medical illness inconsistent with the intervention; and (4) substance abuse or dependence in the past 6 months. Figures 1 and 2 summarize the process of randomization, group allocation, and assessment. The SPIRIT checklist is available in Additional file 1.

Participants, as defined above, will be randomly allocated (a simple randomized sampling will be used) to the trial or control group. Randomization to either trial or treatment as usual will be conducted by independent researchers using a stratified block randomization procedure with a computer-generated allocation sequence. Health experts who will implement the MBIs will be blind to this procedure and will not carry out the assessment.

A mixed qualitative and quantitative analysis method will be used. Qualitative information will be collected by means of semi-structured interviews and assessed with the Grounded Theory. This data analysis approach is widely used in social sciences and was previously applied for the analysis of the subjective experience of patients with psychosis [26]. This methodology will analyze the patients’ subjective experience regarding the feasibility and contribution of this type of intervention in a local context. At the quantitative level, the hypothesis will be contrasted though a mixed designed ANOVA in order to consider both the impacts of the intervention (inter subjects) and time (intra-subject; pre, post, and follow-up measurements) in every variable assessed. The analysis will help prove the hypotheses regarding the efficiency of this intervention in both patient groups. If statistically significant differences are found between the trial and control groups at the beginning of the intervention, corrections will be conducted using an ANCOVA.

The research protocol follows the indications of the Singapore Statement on Research Integrity and has been approved by two ethics committees, namely Pontificia Universidad Católica de Chile and Universidad de Chile.

The research is presently in the sample recruitment phase and the workshops are expected to begin on November 15, 2016.