Asma Fatal

Review
Respiration 2007;74:228–236 DOI: 10.1159/000097676
Received: June 28, 2006 Accepted after revision: September 28, 2006 Published online: November 30, 2006

A Systematic Review of the Psychological Risk Factors Associated with Near Fatal Asthma or Fatal Asthma
G.G. Alvarez a J.M. FitzGerald b
Ottawa Health Research Institute of the University of Ottawa, and Respirology Division,Ottawa Hospital, Ottawa, and b Center for Clinical Epidemiology and Evaluation of the University of British Columbia, and Respirology Division, Vancouver General Hospital, Vancouver, Canada
a

Key Words Systematic review Near fatal asthma Fatal asthma Risk factors

Background

Abstract Psychological factors such as anxiety, depressive disorders and/or personality disorders may predisposepatients with asthma to near fatal asthma (NFA) or fatal asthma (FA). NFA is defined by an asthma exacerbation resulting in respiratory arrest requiring mechanical ventilation or a pCO2 645 mm Hg. Most studies have used the case-control study design. Several studies analyzing the effects of psychological factors on the risk of NFA or FA have shown conflicting results. We reviewed all of the literaturefound by the systematic search done of psychological factors on the risk NFA or FA. A MEDLINE search identified 423 articles between 1960 and March 2006. Seven case-controlled studies were identified following strict applications of the inclusion and exclusion criteria. Due to the significant heterogeneity in the measurement of the psychological factors, a summary statistic was not calculated. Thetrial characteristics were tabulated and qualitative trends were observed to explain the heterogeneity in the results of the studies. Recommendations on future studies in the field are outlined in detail. Following a systematic assessment of all published studies, we cannot conclude that psychological factors increase the risk of NFA and FA.
Copyright © 2006 S. Karger AG, Basel

Approximately300 million people suffer from asthma in the world [1]. It is estimated that asthma accounts for 1 in every 250 deaths worldwide [1]. There are more than 5,000 deaths reported annually in the USA and 100,000 deaths estimated yearly throughout the world [1, 2]. Psychological factors such as anxiety disorders, depressive disorders, coping mechanisms and abnormal family dynamics of asthmatics may beassociated with a higher risk of near fatal asthma (NFA) or fatal asthma (FA). Several hypotheses may explain the link between psychological factors and NFA or FA. Psychological factors may predispose patients directly to an episode of NFA or FA. Emotional factors can be responsible for aggravating or maintaining asthma [3]. Emotionally induced wheezing has been reported in several studies [4].Psychological factors may also be confused with worsening asthma resulting in a vicious circle. For example, worsening of anxiety may be confused with worsening asthma and high levels of -agonist may be inhaled which then results in further worsening of the anxiety [5]. Breathlessness is a common somatic accompaniment of anxiety [6]. Furthermore, the converse may be true, asthma may increase the riskof developing an anxiety disorder [7]. Psychological risk factors may predispose asthmatics to improper asthma management which results in poor asthma control predisposing them to NFA or

© 2006 S. Karger AG, Basel 0025–7931/07/0742–0228$23.50/0 Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com Accessible online at: www.karger.com/res

Dr. Gonzalo G. Alvarez Ottawa Health ResearchInstitute of the University of Ottawa, and Respirology Division, Ottawa Hospital, General Campus 501 Smyth Rd, Box 211, Rm 1835B, K1H 8L6 Ottawa (Canada) Tel. +1 613 737 8899/ext. 78198, Fax +1 613 739 6266, E-Mail galvarez@ohri.ca

Methods
Psychological risk factors

Poor asthma control

NFA or FA

Fig. 1. Hypothetical links between psychological factors and NFA or FA.

Exposure,...