Epidemiologist David Van Sickle spent years studying asthma, but like many researchers of the chronic disease, he was frustrated by the obstacles to determining precise triggers of an individual attack. That frustration gave him an idea for a rescue inhaler topped with a GPS sensor. The invention would map the user's location every time he took a puff and send that information back to his doctor.
Such a device, Van Sickle thought, would give doctors data about when and where attacks occurred, helping them figure out possible environmental causes and allowing them to plan treatment accordingly.
In 2006, he began work on a prototype, an endeavour that turned out to be harder than he had imagined, chiefly because the sensor attachment had to be as durable as the inhalers themselves, which are often jostled around in pants pockets and handbags. 'The first prototypes were very ugly — like a coffee machine alongside of an inhaler,' Van Sickle recalls. He says colleagues joked that just carrying one around might be stressful enough to induce an asthma attack.
Van Sickle and his team continued to fine-tune the technology, forming the start-up company Asthmapolis in 2008. The latest version of the inhalers is equipped with a smaller, Bluetooth-based device that sends usage information to a Web portal where maps show when and where patients have used their inhalers. Rajan K. Merchant, whose Woodland Clinic Medical Group outside Sacramento, Calif., began enrolling patients in another Asthmapolis trial last spring, called the device the first major advance since the advent of the anti-inflammatory steroid inhaler in the 1950s and one that could help patients better manage their disease.
The Asthmapolis inhaler is part of a burgeoning field called geomedicine, which uses geographic information system (GIS) technology to correlate environmental conditions with health risks. The hope is that this data, integrated into a patient's medical history, will help doctors and researchers fine-tune their diagnoses and treatments.
'Place should be a vital sign,' says Ethan Berke, a spatial epidemiologist at Dartmouth Medical School in Hanover.
Doctors have long connected place and health, Berke says, pointing to John Snow, often called the father of modern epidemiology for his work linking London's 1854 cholera outbreak to drinking water contaminated by raw sewage. But today, technology has given them more precise and powerful ways to understand role of location in patients' health.
'I would love it if I could bring up a map and see the grocery stores, parks' that patients have recently visited 'right there while you are checking their blood pressure,' Berke says. Such information would allow him to better tailor his medical advice based on a patient's lifestyle.' I can do that now, but I don't have many GIS tools in the exam room.'
Since many medical conditions, including diabetes and heart disease, are linked to diet and lifestyle, doctors such as Berke who embrace geomedicine think more insight into their patients' lives will help them give advice that will be followed. If a heart attack patient, for instance, lives on the side of mountain on a narrow country lane with no sidewalks, it may be counterproductive to suggest taking daily walks around the block.
One of the chief instigators of this approach is Bill Davenhall, a manager at the GIS software company Esri. After he had a heart attack that he suspected was linked to environmental factors, Davenhall got Esri to build an app that integrates places a person has lived with a report of toxins found within three miles of those locations.
Users can share that information with doctors. Dora Barilla, director of community health development at the medical centre, says that it intends by early March to launch software interfaces that map the health status and local environments of more than a million of its patients.
The medical centre plans to include on