Editorial

Asthma remains a major cause of morbidity and mortality worldwide. In the United States it affects over 14 million people [1]. Acute asthma exacerbations account for almost two million emergency department (ED) visits, 500,000 hospital admissions and 5000 deaths every year [2]. Because of the significant morbidity and economic costs, clinicians are constantly searching for new interventions to treat acutely ill patients as well as more effective ways of using existing agents. Death from acute asthma, many which occur outside the hospital, reflects therapeutic failures at two different levels: failure of prophylaxis and failure in managing the acute attack. The term brittle asthma (BA) was coined initially in 1977 to describe those patients that had wide variations in peak expiratory flow despite high doses of inhaled steroids [3]. This term has evolved to include those patients, who experience sudden, unpredictable, life-threatening asthma attacks as described by the British Thoracic Society [4, 5]. Many of these patients will have multiple visits to EDs and may eventually die. For years, the management of these patients has been a matter of debate. In this issue of Current Respiratory Medicine Reviews, Haqqee presents a comprehensive review on BA including the role of genetics, environmental exposure as well as other factors assumed to cause this management challenge for clinicians [6]. Assessment of patients with BA, particularly when they present to the ED may be a difficult undertaking for any health care practitioner. The patient's signs and symptoms may give a clue as to the degree of airway obstruction in some instances. However, objective measurements of pulmonary function have become the norm. Formal pulmonary function tests (spirometry), is difficult in patients presenting with acute exacerbation of asthma, and the measurement of peak expiratory flow rate has become the standard for ongoing monitoring. Peak expiratory flow rates provide a simple, quantitative and reproducible measure of the severity of airflow obstructions in most patients with asthma. Several clinical studies have found that peak expiratory flow monitoring used as a component of comprehensive asthma self-management improves health outcomes [7-9]. Although dependent on effort and technique, peak expiratory flow rate is a simple procedure that it is easily implemented in several settings. However, in the patient with BA, this commonly used objective measurement of airway obstruction may be misinterpreted and fact, in some patients may be misleading [10]. In some instances, patients may have normal flows and suddenly develop a life-threatening airway obstruction. Clinicians must be careful and recognize that the patient with BA represents a special situation with multiple risk factors, a unique pathogenesis and require very careful monitoring [11]. Even though BA is uncommon, it represents a significant management challenge for clinicians. As Haqqee notes in his review, this multifactorial illness may not respond adequately to conventional therapy. REFERENCES [1] Marano MA. Current Estimates from the National Health Interviewing Survey: United States, 1994. DHHS publication no. (PHS) 96-1521, Vital Health Statistics Series; 10: 193. 1996. Washington, DC, National Center for Health Statistics, US Government Printing Office. [2] Weiss KB, Gergen PJ, Hodgson TA. An economic evaluation of Asthma in the United States. N Engl J Med 1992; 326: 862-866. [3] Turner-Warwick M. On observing patterns of airflow obstruction in chronic asthma. Br J Dis Chest 1977; 71: 73-86. [4] Ayres JG, Miles JF, Barnes PJ. Brittle asthma. Thorax 1998; 53: 315-321. [5] British Thoracic Society, British Paediatric Association, Royal College of Physicians of London, et al. Guidelines on the management of asthma. Thorax 1993; 48 (Suppl): S1-S24. [6] Haqqee R. Brittle asthma. Curr Resp Med Rev 2007; 3: 7-13. [7] Woolcock AJ, Yan K, Salome CM. Effect of therapy on bronchial hyperresponsiveness in the long-term management of asthma. Clin Allergy 1988; 18: 165-76. [8] Ignacio-Garcia JM, Gonzalez-Santos P. Asthma self-management education program by home monitoring of peak expiratory flow. Am J Respir Crit Care Med 1995; 151: 353-9. [9] Beasley R, Cushley M, Holgate ST. A self-management plan in the treatment of adult asthma. Thorax 1989; 44: 200-4. [10] Barnes PJ. Blunted perception and death from asthma. N Engl J Med 1994; 330: 1383-1384. [11] Varon J, Fromm RE. Acute severe asthma. Intensive Care World 1995; 11: 103-104.