Treating anxious expectations can improve dyspnoea in patients with COPD

Abstract

]. Chronic obstructive pulmonary disease (COPD) is a worldwide leading cause of morbidity and mortality and associated with great individual, societal and economic burden [1]. Dyspnoea is the threatening cardinal symptom and related to a worse course of COPD, including drastic reductions in quality of life and even increased mortality risk [2, 3]. Dyspnoea is a multi-dimensional subjective experience that encompasses not only the perception of sensory signals (dyspnoea intensity), but also important immediate and long-term affective aspects (dyspnoea unpleasantness, dyspnoea anxiety, suffering) [2-4]. In many patients, dyspnoea can be persistent, despite optimal treatment efforts, which was recently termed "chronic breathlessness syndrome" [5]. Notwithstanding, reducing dyspnoea is a major treatment goal in COPD [6] and neglecting it has previously been discussed in a thought-provoking article in this journal as a potential violation of human rights [7]. In addition to the prominent pulmonary manifestations of COPD, patients often suffer from various extrapulmonary symptoms and comorbidities, which further add to the burden of the disease [8, 9]. Among these, psychological symptoms, such as anxiety and depression, are very common in COPD and related to various negative health outcomes, including greater dyspnoea [10-12]. For example, COPD patients with high anxiety levels report more dyspnoea during everyday life [13], during pulmonary rehabilitation [14], and during resistive loaded breathing tests [15] compared to patients with low anxiety levels. Alarmingly, comorbid psychological symptoms remain undiagnosed in the majority of COPD patients and, thus, untreated [11]. But how can psychological symptoms such as anxiety lead to greater dyspnoea in COPD patients? Although several potential physiological and behavioural pathways have been suggested [11, 16], respective knowledge remains still limited. Some authors have emphasised that after repeated aversive experiences of dyspnoea, patients develop fear and anxiety and subsequently avoid respective dyspnoea-related situations and contexts such as physical activities. This maladaptive avoidance behaviour can result in progressive deconditioning and physiological deterioration, which further increases dyspnoea at even lower activity levels and contributes to disease progression [17, 18]. Following successful models in other symptom domains, such as the fear-avoidance model of chronic pain [19], especially the anxious expectation or

Reduced neural gating of respiratory sensations is associated with increased dyspnoea perception

“…These findings converge with previous research on other neural gating modalities showing an association between reduced sensory gating and acute painful cold pressor stimulation [15]. Notably, higher anxiety was associated with stronger increases in dyspnoea reports, as well as stronger reductions in neural gating during increasing load levels, which confirms previous observations on either dyspnoea reports or neural gating alone [5][6][7].…”

“…This provides experimental support for the neural gating model of respiratory sensations and might partly be related to attentional processes [1,2]. Moreover, the findings support the view of a gating deficit as a potential mechanism for the common observation of over-perception of dyspnoea in more anxious individuals [1,2,5]. Subsequently, the present findings suggest a potential neural target for pharmacological and/or non-pharmacological treatments which necessitates further studies.…”

Observing dyspnoea in others elicits dyspnoea, negative affect and brain responses

“…This necessitates future studies on vicarious dyspnoea in these caregivers. However, in a more positive vein, vicarious dyspnoea elicited by pictures, videos or even imaginary training [41] might be used in cognitive-behaviourally oriented interventions to desensitise those patients who (due to high levels of anticipatory fear of dyspnoea) avoid dyspnoea-related situations such as physical activities [42,43]. Similarly, vicarious dyspnoea might also be applied in the training of caregivers, who frequently underestimate dyspnoea in patients [44,45].…”

The impact of dyspnea and threat of dyspnea on error processing

“…It can be argued that the anticipation of imminent threat interferes with attentional allocation toward the source of threat and away from task-related errors as suggested by Moser et al (2005). Similarly, threat of dyspnea is a motivationally relevant stimulus that might claim attentional resources (Esser et al, 2017;Stoeckel, Esser, Gamer, Büchel, & von Leupoldt, 2016;von Leupoldt, 2017), which are not available for other cognitive processes (Hayen et al, 2013) in line with previous research on dual-task interference (Pashler, 1994). Notably, we found that threat of dyspnea reduced Pe mean amplitudes also for the correct response, but no effect was found for the Pe difference scores (error minus correct).…”

“…& Pané-Farré, 2017), anxious arousal even at rest (Pappens, Smets, Van den Bergh, & Van Diest, 2012), and the fearful avoidance of situations associated with dyspnea such as physical activity (von Leupoldt, 2017). Dyspnea causes a high socioeconomic and individual burden and is a strong predictor of morbidity and mortality in several patient groups (Banzett & O'Donnell, 2014;Bausewein et al, 2010;Lopez, 2006;Mannino & Buist, 2007;Mentz et al, 2015).…”