Could targeting disease specific fear and anxiety improve COPD outcomes?

KEYWORDS:

• Anxiety
• behavioral therapy
• COPD
• fear
• treatment
• rehabilitation

1. Comorbid psychological symptoms in COPD

Individuals with chronic obstructive pulmonary disease (COPD) frequently suffer from comorbid extrapulmonary symptoms, which contribute to the enormous individual and socioeconomic burden caused by COPD [1,2]. These symptoms include comorbid psychological symptoms, such as anxiety and depression, which are highly common in COPD and related to an unfavorable course of disease including reductions in health-related quality of life (HQoL) and exercise tolerance as well as increases in symptoms, exacerbations, hospitalizations and even mortality [3–5]. A recent review demonstrated that the prevalence of clinical anxiety in COPD, as determined by clinical interviews, ranges from 10% to 55% across studies [6]. The underlying causes for comorbid psychological symptoms in COPD are not well understood, but presumably include various interactions between behavioral, social, and biological factors [4,5]. Notably, these psychological comorbidities are often not diagnosed in patients with COPD and less than one-third of affected patients are receiving respective treatments [5]. The presence of these treatable comorbidities contributes to the high individual and socioeconomic burden of COPD and underscores the urgent need for increased efforts in respective research and clinical practice. One promising strategy is the treatment of disease-specific fear and anxiety. In this editorial, we outline the concept of disease-specific fear and anxiety in COPD and describe respective measurement instruments. Moreover, we present current findings on associations with clinical outcome measures and describe potential treatment approaches. Finally, we discuss the potential of targeting disease-specific fear and anxiety in COPD in order to improve outcomes and list some key needs for future research in this area.

2. Disease specific fear and anxiety in COPD

Over the past few decades, the majority of studies in patients with COPD examined more general forms of anxiety, which can similarly be found in individuals without respiratory disease. These studies mainly relied on various general screening instruments assessing several cognitive and somatic symptoms of anxiety, such as fearful thoughts, worry, restlessness, palpitations, and dyspnea, which might partly overlap with somatic symptoms of COPD and, thus, might even bias estimations of respective prevalence rates. A notable exemption is the recently developed and validated Anxiety Inventory Respiratory (AIR) (AIR) disease scale [7], which avoids items on somatic symptoms and has been shown to be responsive to effects of a pulmonary rehabilitation (PR) program [8]. However, recent studies began to focus on more specific and COPD-related forms of fear and anxiety. These disease-specific fears focus on specific features of COPD patients and their daily lives, which are usually less relevant for individuals without respiratory disease. Examples include negative disease-specific cognitions, beliefs and subsequent behaviors, such as fear/avoidance of activity, fear of dyspnea and fear of disease progression, which contribute to several clinical outcomes even after controlling for general anxiety levels [9,10]. The approach of disease-specific fears in COPD has been adapted from respective approaches in other symptom domains, especially in chronic pain. Here, concepts of pain-specific fear, anxiety, and subsequent avoidance behavior of pain-related situations were successfully established years ago in theory and in respective clinical interventions [11,12]. Several studies demonstrated that pain-specific fears are more strongly correlated with disability than the pain itself (presumably due to subsequent avoidance behaviors), leading to recommendations that their assessment and treatment should be integral part of patient care [11,13]. Transferred to COPD, these approaches suggest that negative beliefs about specific aspects of the disease (e.g. ‘physical activity is harmful for me’) might lead to fear of this aspect (e.g. ‘fear of activity’) and its subsequent avoidance (e.g. ‘activity avoidance’). This results in further disability, for example due to further muscle deconditioning, systemic effects, and increased symptoms, which further reinforce the initial maladaptive beliefs and fears. These circumscribed disease-specific fears can be present in the absence of more general symptoms of fear and anxiety, but might contribute to their development in the longer term.

3. Assessment of disease specific fear/anxiety and associations with clinical outcomes in COPD

Different instruments have been used to assess disease-specific fears and anxiety in COPD patients. One of the oldest examples is the Interpretation of Breathing Problems Questionnaire (IBPQ), which assesses the degree of catastrophizing thoughts about respiratory symptoms using 14 scenarios (e.g. ‘You are at a friends’ house and your chest begins to feel tight’) [14]. Respondents have to answer in a qualitative fashion subsequently scored by raters in terms of catastrophizing tendencies. Although IBPQ scores correlated with general anxiety levels and dyspnea ratings and predicted panic disorder diagnosis [9,14,15], the less practical format may limit the use of this instrument in clinical practice. A more concise measure of catastrophic beliefs about dyspnea is the Breathlessness Catastrophizing Scale (BCS) [13]. The BCS includes 13 items on rumination about dyspnea, magnification of its threat value and perceived inability to control dyspnea (e.g. ‘I become afraid that the breathlessness will get worse’). In COPD patients undergoing a four-week inpatient PR program, breathlessness catastrophizing at PR admission was correlated with other measures of psychological distress, but not with forced expiratory volume in one second (FEV₁) or exercise measures. Interestingly, the subgroup with highest breathlessness catastrophizing at PR admission, showed the greatest improvements in the stair test after PR, but not in other exercise measures. A comparable instrument is the Breathlessness Beliefs Questionnaire (BBQ), which measures beliefs related to fear of dyspnea (e.g. ‘Whenever I feel short of breath my body is telling me something is seriously wrong’) or fear of exercise (e.g. ‘It’s really not safe for a person with a condition like mine to be physically active’). Using the BBQ, Janssens and co-workers [10] assessed dyspnea-related fear in COPD patients before undergoing a 6-month outpatient PR program. At baseline, they found higher dyspnea-related fear to be associated with greater dyspnea during ergometer exercise and with reductions in HQoL and maximal exercise capacity. Interestingly, higher dyspnea-related fear at baseline was associated with greater improvements in dyspnea during ergometer exercise, in HQoL and in maximal exercise capacity after PR. Fischer and colleagues [16] used a Likert-type seven item scale to assess patients’ specific concerns (e.g. ‘some aspects of the rehabilitation program may be harmful to me’) and necessity regarding exercise before and after a 12-week outpatient PR. They found that COPD patients’ concerns, but not the perceived necessity of exercise, were negatively related to exercise performance in a 6-min-walking test (6-MWT) at start of PR, even after controlling for levels of general anxiety. Moreover, in the subgroup with mild-to-moderate airway obstruction (GOLD-level I/II), higher concerns about exercise were related to less improvements in 6-MWT performance after PR. Kühl and colleagues [17,18] developed the COPD-Anxiety-Questionnaire (CAF). In its revised version, the CAF-R is a short (20 items), yet comprehensive measure of different specific fears: fear of social exclusion, fear of dyspnea, fear of physical activity, fear of disease progression, and sleep-related worries [18]. Examples include ‘I feel left alone with my disease’, ‘I avoid activities that accelerate my breathing’ or ‘I fear that I will become in need of care due to my disease’. In regression analyses, these disease-related fears contributed incrementally to disease-specific disability in COPD patients [18], with an additional negative association between fear of physical activity and 6-MWT performance [17]. Using the CAF, this group demonstrated significant associations between disease-specific fears, HQoL, and depression in COPD patients [19,20]. Notably, fear of disease progression and end-of-life fears were reported by many patients suggesting a need for improved management of these specific fears and optimized end-of-life care in COPD patients with advanced disease [20]. Interestingly, disease-specific fears as measured with the CAF have also been shown to be associated with structural brain changes in COPD patients. Specifically, Esser and colleagues [21] recently demonstrated that greater fear of physical activity and fear of dyspnea were correlated with stronger reductions in gray matter volume in the anterior cingulate cortex, which is an important brain area for the processing of emotions as well as bodily sensations including dyspnea.

4. Treatment of disease specific fear and anxiety in COPD

So, should we target disease-specific fear and anxiety in COPD patients in order to improve outcomes? In our opinion, the answer is a clear ‘YES’. As outlined earlier, initial findings suggest that disease-specific fears are important in COPD patients and related to less favorable outcomes in general psychological well-being, exercise performance, dyspnea, and HQoL. Thus, these disease-specific fears might greatly interfere with several effective treatment options, for example exercise programs. Identifying these fears by using available instruments such as the BCS, BBQ, or CAF and subsequently targeting these fears should therefore contribute to more favorable treatment outcomes. Cognitive-behavioral treatment approaches are promising in this respect, including cognitive restructuring [15] and behavioral exposure [22]. The above reported findings by Janssens et al. [10] and Solomon et al. [13] suggest that initially high levels of disease-specific fears might be reduced due to subsequent behavioral exposure strategies, e.g. in a controlled rehabilitation setting, which might contribute to increased engagement in formerly feared/avoided activities, thus contributing to improved rehabilitation outcomes. Furthermore, findings by Livermore et al. [15] show that targeted cognitive treatment of these fears not only prevents the development of panic disorder, but also reduces dyspnea in individuals with COPD. Other treatment examples may include acceptance-based strategies for end-of-life fears, discussions about realistic and unrealistic beliefs about disease progression and motivational support to engage in social activities or self-help groups in order to decrease fears of social exclusion [18].

5. Conclusion

Of course, intensified multidisciplinary efforts and more well-controlled studies are necessary in order to further establish which disease-specific fear is relevant for which subgroup of COPD patients, impacts on which outcome and is sensitive to which type of treatment. The previous successful implementation of approaches on disease-specific fears in the treatment of pain patients [11] strongly encourages similar approaches for COPD patients. Respective first findings are already promising, suggesting that targeting disease-specific fear and anxiety can indeed improve outcomes in COPD patients.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.