Effects of an air pollution personal alert system on health service usage in a high-risk general population: a quasi-experimental study using linked data (7 page pdf, R A Lyons, S E Rodgers, S Thomas, R Bailey, H Brunt, D Thayer, J Bidmead, B A Evans, P Harold, M Hooper, H Snooks, J Epidemiol Community Health, May 23, 2016)
Today we review an analysis of the reaction of an “intervention” group of patients with air pollution- related illnesses (cardio-respiratory and COPD) to alerts produced by the UK’s airAware alert system over a two year period, as measured by visits to hospital emergency departments, compared to a control group which were not similarly afflicted. Results indicate a doubling of emergency admissions and four times the number of respiratory conditions for the intervention group compared to the control group. The authors conclude that some health interventions or alerts beyond a certain distribution level are harmful in terms of health service utilisation.
“The airAware system was a novel development because it integrated near real-time data rather than forecasting. Its design facilitated early identification of local air pollution problems and issued timely warnings of air pollution episodes reflecting levels of particulate matter (measured as particulate matter 10 μm or less in diameter”
“The number of messages per day was limited to three; on any single day no more than three alerts could be issued. Only one alert was issued for the day unless a higher pollution trigger level was met during the daily alerting period.”
“The intervention group experienced a doubling of emergency admissions for all relevant conditions and a fourfold admissions increase for respiratory conditions”
“Our findings raise questions about the trade off between harms and benefits of air pollution alerting services. .. There is a growing evidence base demonstrating some public health interventions are harmful. Wider roll-out of such systems does not appear to be warranted given the current evidence base.“