Nearly 5 million asthmatics have ABPA and could benefit from antifungal therapy
May 08 2013
Researchers in Toronto and Manchester estimate that 4,837,000 adults with asthma have allergic bronchoplulmonary aspergillosis or ABPA, which usually improves substantially with antifungal treatment. Their work, published today in the journal Medical Mycology, has re-estimated the total number of asthmatics worldwide – a remarkable 193 million, of whom 24 million live in the USA, 20 million each in India and China, 13 million in Brazil and 7 million in Japan and the UK. Of these an estimated 1 in 40 (2.5%) suffer from ABPA. This estimate is based on referral to a chest specialist in hospital in 5 countries. This is the first time that a global estimate of ABPA numbers has been made.
In global league tables of ABPA occurrence, New Zealand is top with a 3.5% rate in new patients attending chest clinic at hospital. The rates were 2.6% in Cape Town, 2.3% in Saudi Arabia, 2.5% in China and 0.7% in an older study from Ireland. No population-based studies have been done.
Clinical studies have shown that oral antifungal drugs significantly improve symptoms and asthma control in asthmatics with ABPA, treatment endorsed by the Cochrane Collaboration, based on 2 randomised placebo-controlled studies with oral itraconazole combined with standard asthma therapy. The response rate was about 60%. Antifungal therapy also benefits patients with severe asthma sensitized to fungi, so called SAFS. Alternatives include voriconazole and posaconazole, which have 75-80% response rates. In a recent assessment of voriconazole and posaconazole for both ABPA and SAFS, 75% of patients were able to stop taking oral corticosteroids, a major benefit, and 38% of patients had their asthma severity downgraded on antifungal therapy. This implies that asthma admissions and deaths could be avoided with more extensive use of antifungal therapy.
From Pasqualotto et al 2009
Commenting from the University of Manchester, Professor David Denning, who also works at the University Hospital of South Manchester, said: “We were surprised by the number of patients with ABPA, and by the lack of community based studies done. Our National Aspergillosis Centre treats hundreds of these patients each year, generally with major improvement, and so a conscious program to seek out ABPA from all asthmatics is required.”
Denning DW, Pleuvry A, Cole DC. Global burden of ABPA in adults with asthma and its complication chronic pulmonary aspergillosis. Med Mycol 2013;51:361-70.
To T, Stanojevic S, Moores G, Gershon AS, Bateman ED, Cruz AA, Boulet LP. Global asthma prevalence in adults: findings from the cross-sectional world health survey. BMC Public Health. 2012;12:204
RCTs A randomized trial of itraconazole in allergic bronchopulmonary aspergillosis Stevens DA, Schwartz HJ, Lee JY, Moskovitz BL, Jerome DC, Catanzaro A, Bamberger DM, Weinmann AJ, Tuazon CU, Judson MA, Platts-Mills TA, DeGraff AC Jr. . N Engl J Med. 2000;342:756-62.
Anti-inflammatory effect of itraconazole in stable allergic bronchopulmonary aspergillosis: a randomized controlled trial. Wark PA, Hensley MJ, Saltos N, Boyle MJ, Toneguzzi RC, Epid GD, Simpson JL, McElduff P, Gibson PG. J Allergy Clin Immunol. 2003;111:952-7.
Alternative antifungal therapy Chishimba L, Niven RM, Cooley J, Denning DW. Voriconazole and posaconazole for ABPA and SAFS – clinical benefit and reduction in asthma severity. J Asthma 2012;49:423-33.