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Hidden Risk Population Identified for Thunderstorm Asthma

A “potentially hidden and significant population susceptible to thunderstorm asthma” has been described at the Thoracic Society for Australia and New Zealand’s annual scientific meeting. “Many more people than previously thought are at risk of sudden, unforeseen asthma attack,” said TSANZ President Prof Peter Gibson.

Nine people died in Victoria late last year and more than 8500 required emergency hospital care when a freak weather event combining high pollen count with hot winds and downpours of rain led to the release of thousands of tiny allergen particles, triggering sudden and severe asthma attacks. Those most seriously affected were people who were unaware they were at risk of asthma and therefore had no medication at hand.

In a study of more than 500 healthcare workers led by the Department of Respiratory and Sleep Medicine at Eastern Health, almost half the respondents with asthma experienced symptoms during the thunderstorm event. Most took their own treatment, a few sought medical attention and one was hospitalised. However, 37% of respondents with no prior history of asthma reported symptoms such as hayfever, shortness of breath, cough, chest tightness and wheeze during the storms.

The study also found that people with a history of sensitivity to environmental aeroallergens, such as rye grass or mould, were far more likely to report symptoms than those with a history of either no allergy or allergy to dust mites or cats. Being indoor or outdoor did not affect the risk of asthma.

“This study gives us an indication of the proportion of our population that might be at risk of thunderstorm asthma, but is unaware of it as they have no history of asthma. It also suggests that a history of hayfever is one of the greatest risk factors,” said lead researcher Dr Daniel Clayton-Chubb of Eastern Health.

“The key message from our work is that anyone with hayfever should ensure that they have ready access to quick-acting asthma treatments such as bronchodilators at all times, but particularly in pollen season or if thunderstorms are predicted,” he said. “Severe thunderstorm asthma symptoms can strike rapidly and without warning.”