Antifungal therapy could help 5 million asthmatics
14 May 2013
A new estimate of the global numbers suffering from allergic
bronchopulmonary aspergillosis (ABPA) shows an estimated 4.8 million
asthmatics could benefit substantially from antifungal treatment.
The study, by researchers from The University of Manchester and
the University of Toronto and published in the journal Medical
Mycology, has also re-estimated the total number of asthmatics
worldwide — a staggering 193 million sufferers. Twenty-four million
asthma sufferers live in the United States, 20 million each in India
and China, and seven million in the United Kingdom.
Clinical studies have shown that oral antifungal drugs
significantly improve symptoms and asthma control in asthmatics with
ABPA, treatment endorsed by the Cochrane Collaboration. This is the
first time that a global estimate of ABPA numbers has been made.
In national league tables of asthma rates in adults, only
Australia and Sweden have a higher prevalence than the UK. In global
league tables of ABPA occurrence, New Zealand tops the list with a
3.5% rate in new patients attending chest clinics at hospitals. 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.
In addition to standard asthma therapy, the antifungal therapy
used is itraconazole — now a generic, inexpensive antifungal — with
a response rate of 60%. The researchers also found that antifungal
therapy also benefits patients with severe asthma sensitized to
fungi, 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.
Professor David Denning, Professor of Medicine and Medical
Mycology at The University of Manchester and Director of the
University Hospital of South Manchester’s National Aspergillosis
Centre, led the study into the total number of asthmatics worldwide.
He said the study results implied that asthma admissions and deaths
could be avoided with more extensive use of antifungal therapy.
“We were surprised by the number of patients with ABPA, and by
the lack of community based studies done,” he said. “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 allergic
bronchopulmonary aspergillosis with asthma and its complication
chronic pulmonary aspergillosis in adults. Medical Mycology, 2013
May;51(4):361-70. doi: 10.3109/13693786.2012.738312