Australasian Science: Australia's authority on science since 1938

Expensive Electricity Increases Asthma

By Stephen Luntz

Asthma attacks have been linked to the price of electricity, with a study finding that hospital admissions rise when prices are higher.

New Zealand is known as an asthma hotspot, in part because the cool, damp climate encourages the growth of dust mites. Keeping houses warm in winter can reduce dust mite concentrations, but Dr Andrea Menclova of the University of Canterbury’s School of Economics and Finance found that more people were admitted to hospital for severe asthma attacks when electricity prices are high. She suggests this may be because people turned down the thermostat.

Menclova and her PhD student, Rachel Webb, compared the admissions in New Zealand’s 21 district hospital boards over 9 years to electricity prices over that time, controlling for rainfall, temperature and income levels. Although factors such as inadequate fruit consumption, second-hand smoke and even the start of the school year can raise asthma rates, the effect of electricity prices was visible.

There are 130 deaths from asthma per year in New Zealand, with an estimated $700 million in indirect costs to the economy plus $125 million in direct costs. Menclova does not argue for keeping electricity prices low but suggests: “If people adjust to higher electricity prices by improving the efficiency of their home heating, allowing them to have increased heating for the same cost, this should improve asthma symptoms and lower the number of asthma admissions”.

“Randomised studies in New Zealand and the UK have shown that installing insulation in roofs and heat pumps can offer benefits in asthma incidence, but the effect is not very large so it is not clear if this would be a cost-effective approach,” Menclova says.

Even after factoring in the weather, Menclova says that asthma rates were higher in more southern districts for reasons that are unclear.