Role of counter-conditioning in the treatment of asthma

A review of psychological dysfunction in asthma: affective, behavioral and cognitive factors

BACKGROUND

The research on psychological dysfunction in asthma is extensive but heterogeneous. We undertook a narrative review about the effects of psychological dysfunction on asthma.

METHODS

Electronic searches of MEDLINE, EMBASE, CINAHL and the Cochrane Library were conducted, supplemented by hand-searching bibliographies and seeking expert opinion.

RESULTS

The impact of psychological factors on asthma can be classified according to dysfunction in the domains of affect, behavior and cognition. Affective or emotional disturbance may lead to poor asthma control by directly modulating disease activity. Maladaptive behaviors may occur in asthma patients. These include maladaptive breathing behaviors, such as impaired voluntary drive to breathe and dysfunctional breathing, as well as impaired asthma health behaviors, that is, a coordinated range of activities performed to maintain good disease control. Dysfunctional cognitions (thoughts and beliefs) about asthma and impaired cognitive processing of the perception of dyspnea are associated with poorly controlled disease and asthma deaths, respectively. The three domains of psychological dysfunction are often closely intertwined, leading to vicious circles.

CONCLUSIONS

We have conceptualized psychological dysfunction in asthma using a framework consisting of affect, behavior and cognition. Their influences are intertwined and complex. Future research should focus on the formulation of a psychological assessment tool based on this framework and evaluating its efficacy in improving asthma outcomes.

Undertaking a systematic review: the road to successful completion

Abstract

The systematic review is an important research method that allows for the critical analysis of the results from a range of existing studies to answer research questions. The findings can be used to inform clinical decisions, as well as the development of protocols and guidelines. The aim of this paper is to explore the steps involved in undertaking a Cochrane systematic review and to encourage more nurses to participate in this world wide collaboration to answer questions that are relevant to nursing practice. The first stage of a review involves initiating a focussed clinical question in which the patient group or problem is identified as are the intervention, comparison and outcome, which will become the focus of study. Each review is guided by a protocol that is subject to peer review and followed by a structured search of the worldwide literature on the subject. Quality assessment and data extraction are done systematically and subject to cross-checking. The results are analysed using statistical methods, including meta-analysis. Publication is electronic in the Cochrane Library and many will also be published in other journals. As with all research, findings should be presented in a way that enables the reader to assess whether the review can be applied to their patient.

A systematic review of psychological interventions for children with asthma

AIM

Psychological factors may influence the symptoms and management of asthma in children in many ways. It is, therefore, suggested that psychological interventions may be appropriate for this population. This paper reports a systematic review assessing the efficacy of psychological interventions in improving health outcomes for children with asthma.

METHODOLOGY

A review of Randomized Controlled Trials (RCT) was designed. RCTs assessing the effects of a psychological intervention in child participants were included in the review. Outcome measures included healthcare utilization, lung function, asthma symptoms, and psychological health status. The search was conducted until April 2005.

RESULTS

Twelve studies, involving 588 children, were included in the review; however, study quality was poor and sample sizes were frequently small. A meta-analysis was performed on two studies, examining the effects of relaxation therapy on PEFR which favored the treatment group (SD 0.82, CI 0.41-1.24). No other meta-analysis could be performed due to the diversity of interventions and the outcomes assessed. In addition, many studies reported insufficient data.

CONCLUSIONS

This review was unable to draw firm conclusions for the role of psychological interventions for children with asthma. We recommend that valid outcome measures for evaluating the effectiveness of psychological interventions for children with asthma need to address adjustment to and coping with asthma, as well as other psychological indicators. The absence of an adequate evidence base is demonstrated, highlighting the need for well-conducted RCTs in this area.

Psychological interventions for children with asthma

BACKGROUND

Asthma is a chronic disease of inflammation and smooth muscle dysfunction, including bronchoconstriction. These symptoms are usually associated with widespread but variable airflow obstruction that is often reversible either spontaneously or with treatment. Psychological factors may influence the symptoms and management of asthma in children in many ways, for example, evidence suggests that emotional stress can either precipitate or exacerbate both acute and chronic asthma.

OBJECTIVES

To assess the efficacy of psychological interventions in improving health and behavioural outcomes for children with asthma.

SEARCH STRATEGY

The Cochrane Airways Group Specialised Register and PsycINFO were searched with pre-defined terms up until March 2005.

SELECTION CRITERIA

Randomised controlled trials published in any language assessing the effects of a psychological intervention compared with a control intervention in children and adolescents with asthma were included in the review. Cross-over trials were considered inappropriate for studies using psychological interventions and were therefore excluded from this systematic review.

DATA COLLECTION AND ANALYSIS

Two reviewers assessed the relevance of abstracts identified by electronic searching and retrieved agreed studies for further scrutiny. The studies that met the inclusion criteria were assembled and data extracted.

MAIN RESULTS

Twelve studies (588 children) were included in the review. Study quality was poor and sample sizes were frequently small. A meta-analysis was possible on two studies only examining the effects of relaxation therapy on PEFR which favoured the treatment group (32 L/min, 95% CI 13 to 50 L/min). No other meta-analysis could be performed due to the diversity of interventions and the outcomes assessed. In addition, many studies reported insufficient data.

AUTHORS' CONCLUSIONS

This review was unable to draw firm conclusions for the role of psychological interventions for children with asthma. This review demonstrates the absence of an adequate evidence base and highlights the need for well-conducted and reported randomised trials in this area.

The effects of suggestion on airways of asthmatic subjects breathing room air as a suggested bronchoconstrictor and bronchodilator

Thirty-three asthmatic subjects were told they were receiving, alternately, an inhaled bronchoconstrictor and inhaled bronchodilator, although they actually were only breathing room air. No subjects showed suggestion-produced effects on FEV1, although two (of the 19 on whom FEF50 was measured) showed effects of greater than 20% on measures of maximal midexpiratory flow. The incidence of the effect is smaller than reported previously, possibly because some subjects in previous studies inhaled saline, a mild bronchoconstrictor, and reversal of effect was not required for classification as a reactor. Higher percentages of subjects in this study showed decreased MMEF in response to the 'bronchoconstrictor', but this appeared to reflect fatigue rather than suggestion effects. However, the fact that the effect occurred in a relatively non-effort-dependent measure suggests that real changes occurred in bronchial caliber, not just in test effort. Suggestion had a significant effect on perception of bronchial changes, but the correlation between actual and perceived changes was minimal. There was an increase in FVC prior to administration of the 'bronchoconstrictor', possibly reflecting a preparatory response to the expected drug. Correlations among self-report variables suggested the existence of three personality dimensions among our population related to suggestion and asthma: cognitive susceptibility to suggestion of bronchial change; feeling of physical vulnerability; and anxiety. However, there was no significant relationship between airway response to suggested changes and hypnotic susceptibility, as measured by the Harvard Group Scale of Hypnotic Susceptibility.