SAN FRANCISCO--(BW HealthWire)--Feb. 24, 1997— A novel device has been tested by University of California (UC) at San Francisco researchers that may help both asthma sufferers and their doctors control the disease. The findings were presented today at the meeting of the American Academy of Allergy, Asthma and Immunology, in San Francisco.
Homer Boushey, M.D., chief of the Asthma Clinical Research Center at UCSF and professor of medicine, and Susan Janson, DNSc, RN, UCSF professor of community health systems and medicine, joined with Richard Martin, M.D., at National Jewish Hospital in Denver, and colleagues in the NIH-supported Asthma Clinical Research Network, to evaluate a new inhalation device that both records and regulates the amount of asthma drug inhaled by people with asthma.
According to Boushey, who presented the group findings, the SmartMist device ensures that the doctor will know if the patient actually took the medication as often as prescribed and used the correct technique. The device thus enables physicians and researchers to determine if the treatment they are testing actually works.
The SmartMist, made by the Hayward, Calif., company, Aradigm, contains a microprocessor that regulates the release of asthma drugs from an inhaler, so that it is only released if the patient is using correct inhalation technique. The device releases the drug shortly after inhalation has started and then only if the person breathes at a specific, slow rate. In addition, the device provides visual feedback telling the patient to continue inhaling and to hold his or her breath for 10 seconds, thus serving as an educational tool.
The SmartMist also records how the medication was inhaled, as well as the time and date of each use. It can also act as a peak flow meter, measuring the patient's peak air flow.
In the study performed by the UCSF and Denver groups, 20 asthma patients used the SmartMist device and 20 used an ordinary inhaler equipped with a recording device to take their asthma medication. They were asked to record their inhalations and other information in an asthma diary.
The biggest difference between the groups was in the way the patients used their inhalers. Over 90 percent of the puffs taken from the SmartMist were taken correctly. This was true of less than 50 percent of the puffs taken in the usual way. The device also seemed to enhance the regularity of use of the twice-a-day inhaler.
After the first week of the study, the patient diary entries were compared to the asthma device recordings. Fourteen of the 40 subjects had recorded one or more data points in their diary at times they appeared not to have done an inhalation or peak flow measurement.
"People find it tedious to record the amount of drug taken and their peak flow values accurately, especially when they have to do it twice a day,” according to Boushey. “Sometimes people make simple transcription errors when they record the numbers they see on their peak flow meters into their asthma daily diaries.
"The study patients are conscientious, reliable people who do not want to disappoint their doctors, so it might be that they filled out several days of their diaries at one sitting, trying to recall data from two or three days before. Memory is fallible, so we then discussed these results with each patient," said Boushey. Over the next two weeks, results showed perfect concordance between the diary data points and those their device records, according to Boushey.
Asthma has increased dramatically over the past 20 years, especially in developed Western countries, Boushey said. Many new asthma treatments are under development and will need to be tested in the next 10 to 20 years and devices such as the SmartMist may prove helpful to medical researchers who are trying to determine if the drugs they are testing really help control asthma, he added. The device also has great potential for teaching people correct techniques for using inhalers, he said.
The National Heart, Lung and Blood Institute established the Asthma Clinical Research Network to conduct clinical trials not routinely carried out by drug companies.
