The mediating effect of mindful non-reactivity in exposure-based cognitive behavior therapy for severe health anxiety
Introduction
Core features of severe health anxiety, in this paper defined as DSM-IV hypochondriasis American Psychiatric Association (1994), are a persistent fear of developing serious somatic disease, and misinterpretation of benign bodily sensations. Severe health anxiety is highly prevalent in medical settings, associated with functional disability and rarely remits if untreated (Barsky, Fama, Bailey, & Ahern, 1998; Sunderland, Newby, & Andrews, 2013; Tyrer et al., 2011). In the last 20 years, there has been a rapid development in psychological treatment of the disorder and several randomized controlled trials have shown that cognitive behavior therapy (CBT) is highly effective in reducing health anxiety (Olatunji et al., 2014).
Our research group has developed an exposure-based CBT protocol (Hedman et al., 2011; Hedman, Axelsson, Andersson, Lekander, & Ljotsson, 2016b; Hedman et al., 2014), which assumes that severe health anxiety is perpetuated by the avoidance of health anxiety-eliciting stimuli. The main component of the treatment is therefore systematic exposure to such stimuli, which may be both external (e.g., hospitals) and internal (e.g., a pounding heart or an intrusive thought about becoming ill). As a means to increase the willingness to undergo exposure, which is often highly anxiety-provoking, the treatment also includes mindfulness training. Mindfulness training is used solely as a means to increase the effect of exposure; not as a stand-alone intervention as in the mindfulness-based treatment for health anxiety developed by McManus, Surawy, Muse, Vazquez-Montes, and Williams (2012). As one part of mindfulness involves observing internal events without attempting to change their form (e.g. Kabat-Zin, 1994), we regarded it as potentially useful for persons with severe health anxiety when conducting exposure. The treatment has been shown to be effective in three randomized controlled trials and has demonstrated cost- and long-term effectiveness (Hedman et al., 2013b; Hedman, Andersson, Ljotsson, Axelsson, & Lekander, 2016a; Hedman et al., 2011, Hedman et al., 2014). In these trials, exposure-based CBT was administered as a therapist-guided Internet-delivered treatment. This delivery model confers several advantages such as increased treatment accessibility and high control over the treatment content to which the patient is exposed (Hedman, Ljótsson, & Lindefors, 2012).
Despite the strong empirical support for CBT in the treatment of severe health anxiety studies investigating mediators, potential treatment mechanisms, are scarce. As stated by Kraemer, Wilson, Fairburn, and Agras (2002) studying mediators is one of the central questions of modern psychiatry as it can lead to development of more effective treatments or to treatments that have similar effectiveness but at a lower cost.
Only a handful studies have examined potential mediators in treatment studies for health anxiety. In a recent study that employed a design where the putative mediator and outcome were assessed before and after treatment, Weck, Neng, Schwind, and Hofling (2015a) demonstrated that reduction of dysfunctional attributions of somatic symptoms mediated treatment effect in both exposure-based and cognitive therapy. Based on data from the same trial, the same research group also found that therapist competence was associated with outcome and that this relationship was mediated by therapeutic alliance (Weck, Richtberg, Jakob, Neng, & Hofling, 2015b). In a non-clinical sample Olatunji, Etzel, Tomarken, Ciesielski, and Deacon (2011) showed that increasing safety behaviors led to increased health anxiety and that this effect was mediated by changes in health-related thoughts.
A potential explanation for the lack of mediation studies is that high methodological quality requires that both the mediator and the outcome are assessed frequently with tight intervals during the treatment so that individual differences can be adequately modeled to avoid biased longitudinal mediation effects (e.g. Maxwell & Cole, 2007; Maxwell, Cole, & Mitchell, 2011). In the field of severe health anxiety, we have only found one study meeting those criteria. In that study the findings showed that reduced perceived risk of disease, less attention to bodily symptoms and reduced intolerance of uncertainty mediated improvement in health anxiety in exposure-based CBT (Hedman et al., 2013a). As the investigated treatment was exposure-based these processes were only to a limited extent directly targeted, i.e., they were most likely changed as a consequence of exposure, which led to improvement in health anxiety. Because the treatment entails mindfulness training as a means to enhance exposure, we viewed it as important to investigate increased mindfulness as a putative mediator of improvement in exposure treatment.
A specific facet of mindfulness that, to our knowledge, has not been previously studied as a mediator in the context of exposure-based CBT for health anxiety is mindful non-reactivity. Mindful non-reactivity is a core aspect of mindfulness and refers to the process of observing thoughts, emotions and bodily sensations without reacting to them (Baer, Smith, Hopkins, Krietemeyer, & Toney, 2006). For several reasons, the potential mediating role of mindful non-reactivity in exposure-based CBT is highly relevant to investigate. First, as reported by Muse, McManus, Hackmann, Williams, and Williams (2010) health anxiety is marked by intrusive thoughts of life-threatening illness and death and these thoughts serve as cues for checking behaviors, avoidance and distraction. As intrusive thoughts are future-oriented and hard to disconfirm directly, the authors suggest that mindfulness training is a logical treatment component as it could be a means to change the function rather than the form of the intrusions (Muse et al., 2010). Second, as exposure and response prevention by definition means staying in contact with an aversive stimulus while refraining from avoidance or control behaviors (Barlow, Allen, & Choate, 2004) it is highly likely that there will be positive feedback loops between mindfulness training, exposure exercises and mindful non-reactivity. One of several possibilities is that mindfulness training leads to an increased capacity for mindful non-reactivity, which increases the chance of conducting successful exposure and response prevention, which in turn further strengthens the person's ability to observe without reacting, and so forth. This is in line with empirical studies that have shown that mindfulness is associated with increased willingness to conduct exposure (Arch and Craske, 2006, Arch and Craske, 2010). Third, as postulated by theorists, the process of being mindful could not only increase fear tolerance but in itself be viewed as exposure to multiple conditioned stimuli such as physical sensations, emotions, and cognitions (Treanor, 2011), which may in part explain the effect of mindfulness-based treatments for anxiety disorders. Fourth, two previous studies based on clinical trials of treatment for health anxiety showed that mindfulness processes mediated the effect in mindfulness-based cognitive therapy (McManus et al., 2012) and Acceptance and Commitment Therapy (ACT) (Eilenberg, Hoffmann, Jensen, & Frostholm, 2017), respectively.
Although the Five Facet Mindfulness Questionnaire (FFMQ) (Baer et al., 2006), which is probably the most widely used measure of mindfulness processes, is comprised of not just non-reactivity but also of facets relating to for example acting with awareness, observing, and describing not all of these processes might be equally important when it comes to explaining effects of exposure treatment for health anxiety. We viewed mindful non-reactivity a specifically relevant potential mediator in this context. This is because it is plausible that non-reactivity, for which a typical item of the FFMQ reads “Usually when I have distressing thoughts and images, I just notice them and let them go”, is important when one is deliberately aiming to stay in contact with aversive internal events, i.e., when conducting systematic exposure. In contrast, the other facets of mindfulness as assessed with the FFMQ, which have items such as “I notice the smells and aromas of things” (observing) and “I find myself doing things without paying attention” (acting with awareness), were judged to be of less potential relevance in the context of exposure therapy. For this reason, we decided to collect mediation data using only the non-reactivity subscale of the FFMQ and not the other subscales. Also, a recent study investigating mediation in ACT for health anxiety using the full FFMQ found that mindful non-reactivity, but not the other facets of FFMQ, significantly mediated improvement (Eilenberg et al., 2017), thus indicating that non-reactivity is a mindfulness process of special importance in health anxiety treatment. As noted above, gaining more knowledge about mindful non-reactivity as a potential mediator could provide new valuable information on how to improve psychological treatment for severe health anxiety.
The aim of this study was to investigate mindful non-reactivity as a putative mediator in exposure-based CBT for severe health anxiety. The study was conducted in the context of a randomized controlled trial using an active control condition that received behavioral stress management (BSM). Treatments were delivered via the Internet and the main outcome study showed that, compared to BSM, exposure-based CBT led to superior reductions in health anxiety (Hedman et al., 2014). We expected that improvements in health anxiety would be mediated by mindful non-reactivity, that there would be a significant effect of treatment (CBT vs. BSM) on the mediator (α-path), a significant effect of the mediator on the outcome (β-path), and a significant indirect mediational effect (αβ).
Section snippets
Design
This was a mediation study based on data from a clinical trial where adult participants with severe health anxiety (N = 158) were randomized to Internet-delivered exposure-based CBT (N = 79) or BSM (N = 79) in a 1:1 ratio without restriction. As reported previously (Hedman et al., 2014) both treatments were 12 weeks long and the study was conducted in Stockholm, Sweden. Participants provided informed consent and the study was approved by the Regional Ethics Review Board in Stockholm. Analyses
Data completion
Across all measurement points, participants completed on average 83% of the assessments on the outcome SHAI and the mediator FFMQ-non-reactivity. The mediation analysis was thus based on a total of 1443 individual assessments of each measure. Throughout, full information maximum likelihood (FIML) was used to estimate model parameters, which provides unbiased estimates in the presence of missing data under the less restrictive missing at random assumption (Hesser, 2015).
Average growth and individual heterogeneity: unconditional growth models
Table 1 provides the
Discussion
The aim of this study was to investigate mindful non-reactivity as a putative mediator in exposure-based CBT for severe health anxiety using data from a large scale randomized controlled trial. The results from the latent growth model analyses supported our hypothesis that there would be a significant effect of treatment on the mediator (α-path), a significant association between the mediator and the outcome (β-path), and a significant indirect effect (αβ). In other words, this study
Author contributions
All authors contributed substantially in the conception of the study and in the analysis or interpretation of the data. In addition, all authors approved of the final version of the manuscript and contributed substantially in the drafting of it.
Declaration of interest
The main funding organizations (Karolinska Insititutet and Stockholm County Council) are public institutions and had no role in the design and conduct of the study; in the collection, management, and analysis of the data; or in the preparation, review and approval of the manuscript.
References (50)
- et al.
Health anxiety, hypochondriasis, and the anxiety disorders
Behavior Therapy
(2007) - et al.
The Short Health Anxiety Inventory: A systematic review and meta-analysis
Journal of Anxiety Disorders
(2013) - et al.
Mechanisms of mindfulness: Emotion regulation following a focused breathing induction
Behaviour Research and Therapy
(2006) - et al.
Laboratory stressors in clinically anxious and non-anxious individuals: The moderating role of mindfulness
Behaviour Research and Therapy
(2010) - et al.
Toward a unified treatment for emotional disorders
Behavior Therapy
(2004) - et al.
Intervening variables in group-based acceptance & commitment therapy for severe health anxiety
Behaviour Research and Therapy
(2017) - et al.
Psychometric properties of Internet-administered measures of health anxiety: An investigation of the Health Anxiety Inventory, the Illness Attitude Scales, and the Whiteley Index
Journal of Anxiety Disorders
(2015) - et al.
Internet administration of self-report measures commonly used in research on social anxiety disorder: A psychometric evaluation
Computers in Human Behavior
(2010) Modeling individual differences in randomized experiments using growth models: Recommendations for design, statistical analysis and reporting of results of internet interventions
Internet Interventions
(2015)- et al.
United we stand: emphasizing commonalities across cognitive-behavioral therapies
Behaviour Therapy
(2013)
Intrusive imagery in severe health anxiety: Prevalence, nature and links with memories and maintenance cycles
Behaviour Research and Therapy
The effects of safety behaviors on health anxiety: an experimental investigation
Behaviour Research and Therapy
Cognitive-behavioral therapy for hypochondriasis/health anxiety: A meta-analysis of treatment outcome and moderators
Behaviour Research and Therapy
Fear activation and distraction during the emotional processing of claustrophobic fear
Journal of Behavior Therapy and Experimental Psychiatry
The potential impact of mindfulness on exposure and extinction learning in anxiety disorders
Clinical Psychology Review
Prevalence of health anxiety problems in medical clinics
Journal of Psychosomatic Research
Dysfunctional beliefs about symptoms and illness in patients with hypochondriasis
Psychosomatics
Exposure therapy changes dysfunctional evaluations of somatic symptoms in patients with hypochondriasis (health anxiety): A randomized controlled trial
Journal of Anxiety Disorders
Therapist competence and therapeutic alliance are important in the treatment of health anxiety (hypochondriasis)
Psychiatry Research
Applied relaxation: description of a coping technique and review of controlled studies
Behaviour Research and Therapy
Diagnostic and statistical manual of mental disorders: DSM-IV
Internet-based vs. face-to-face cognitive behaviour therapy for psychiatric and somatic disorders: a systematic review and meta-analysis
World Psychiatry
Using self-report assessment methods to explore facets of mindfulness
Assessment
A Prospective 4- to 5-Year Study of DSM-III-R Hypochondriasis
Archives of General Psychiatry
Investigation of mediational processes using parallel process latent growth curve modeling
Structural Equation Modeling: A Multidisciplinary Journal
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