Monitoring asthma at home can expand patients’ compliance with testing and medication measurements prescribed by their health providers.

 Asthma monitoring software.

Asthma is the most common chronic disease in the United States, affecting more that 15 million persons in 1995. Asthma causes more than 1.5 million emergency department visits, approximately 500,000 hospitalizations, and more than 5,500 deaths per year. Missed school days due to asthma also account for approximately 14 million school absences peryear.1 The estimated direct and indirect costs for the disease totaled $11.3 billion in 1998.2 Portable electronic monitoring devices that are used by patients in the home can expand compliance with testing and medication measurements as prescribed by their health providers. The rapid growth of the Internet as a common part of home life has given a promise of real-time monitoring of compliance using several new technological innovations.

There are two questions that need to be answered when it comes to monitoring patients’ asthma in the home. First, can the patients, many of whom may not be technologically adept, readily accept and use the new technology? Second, can it be determined that the overall cost of the technology is cost-effective?

Several successful models have demonstrated that telemedicine is redesigning patient care through customized and continuous care, rapid sharing of data, coordination of therapy, and evidence-based decision support—all with the patient as the control point. For example, a home monitoring program using a personal computer that incorporates spirometry, blood pressure, and pulse oximetry data into a respiratory assessment profile can facilitate the effective management of patients with asthma and lung transplantations. Patients can use portable spirometry devices and palmtop computers to transmit test results from home to the medical center for physician review using a Web browser. The system can perform initial error detection, exchange information, and analyze data trends.3

A recent study4 was conducted with the objective of evaluating the validity of spirometry self-testing during home telemonitoring and assessing the acceptance of an Internet-based home asthma telemonitoring system by asthma patients. The study was designed to use an Internet-based telemonitoring system that collected spirometry data and symptom reports from asthma patients’ homes for review by physicians in the medical center’s clinical information system. After a 40-minute training session, patients completed an electronic diary and performed self-spirometry testing twice a day for 3 weeks. The setting was in a low income inner city area. These patients were not computer-literate and the majority characterized the self-testing procedure as “not complicated.”

Educational Issues
There are several educational issues that should be addressed when using electronic asthma monitoring equipment. Jud Schoendorf, MD, MBA, chairman of the American Lung Association of Los Angeles County and chair of the Professional Practices Workgroup of the Long Beach Alliance for Children with Asthma, Long Beach, Calif, says, “Electronic monitoring equipment, while promoting accuracy and better disease management, still requires compliance from both the patient and the physician. The physician needs to be aware of how and when to respond.” In addition, the cost of the devices and who should pay for the equipment and decide who receives this new technology are issues that must be addressed. Many newly diagnosed asthma patients are young children, and educational and medical compliance of these patients is also an important concern. Johanna Goldberg, director of Community Outreach and Education at Los Angeles Care Health Plan, says, “When a young child is diagnosed with asthma, the entire family becomes involved. Asthma management comes from educating children and their parents. Understanding the physiology, the importance of medications, and using devices properly is all part of managing the disease.” While the new generation is learning more about computer technology in the classrooms, Schoendorf asks one question related to compliance by both younger and older patients, “How long are asthma patients going to keep using the new reporting technology once the novelty wears off?”

There are several devices in the marketplace, ranging from simple electronic devices that give a patient a count of the medication left in their metered dose inhaler (MDI) to electronic equipment monitoring all aspects of a patient’s health using the Internet. These devices serve two important purposes. The patient is spared the anxiety of an unexpected task and thus is given a sense of control over the disease; in addition, the treating physicians and therapists collect valuable trend data for long-term therapeutic planning.

Tracking Device
There is a simple device that tracks the use of medication taken from an MDI. This innovative device has a self-contained microcomputer, which counts and displays the number of inhalations remaining in the inhaler and displays the number of inhalations taken in the current day. The device also stores the number of inhalations taken in each of the last 30 days in its memory and alerts the user when the MDI is nearly empty. The MDI use tracker has a self-contained battery that lasts a full year.

This tracking device eases patients’ worries of running out of rescue medication and eliminates the fear and anxiety of being caught with an empty inhaler just when they might need it most. Knowing when the inhaler is nearly empty is difficult at best; patients cannot look inside to see how much medication is left. Shaking or floating the inhaler is only guesswork and can leave patients unprepared. With this device, they always know exactly how many inhalations are left in the canister at all times.5 This is a relatively inexpensive device for maintaining patient compliance and confidence with a cost of around $35.

Portable Devices
Mechanical devices for patients’ personal use, such as the peak flow meter, have been available for several decades for serial monitoring of lung function. They have proven quite useful in managing asthma. Most peak flow meters are robust and provide reproducible results essential for serial monitoring. However, they often have limited accuracy, and, because they provide only a single effort-dependent index of ventilatory function, they have limited application in the initial assessment of respiratory diseases; as the data collection increases, it becomes more useful for long-term therapy.

Measurements of peak expiratory flow are reduced in diseases causing airway obstruction. Peak flow monitoring is particularly useful for following trends in lung function, quantifying response to treatment, and identifying trigger factors in asthma.

Peak flow meters vary considerably in accuracy between brands and this is sometimes due to the complex (nonlinear) physical characteristics of the spring component. One way of overcoming this problem and thus enhancing the device’s accuracy is to use a flow-proportional measurement scale. Most manufacturers of peak flow meters now use them.

Recently, several small, inexpensive, yet accurate battery-powered devices have been developed—some of which can store the test data to be downloaded onto a computer for review and statistical analysis.

With continued advances in flow sensor technology, the traditional peak flow meter may well be replaced by inexpensive electronic portable spirometers. These devices are capable of accurately measuring several indices of ventilatory function, and storing the results together with the date and time will facilitate subsequent analysis by the physician.6

Portable Devices Using Telemetry
There are devices that combine spirometers (peak flow) and pulse oximeters with an enhanced internal memory chip to accommodate delayed data transmission. The benefits of daily monitoring can be extended to patients suffering from a range of chronic diseases, even when they are away from home.

This device can connect to and transmit physiological data from measurement devices used by patients with respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD). For disease management companies currently receiving daily physiological data from patients via hand-written journals or interactive voice response (IVR) methods, this device will eliminate inaccurate readings, costly human errors, and noncompliance issues. Since data are collected directly from the measurement device and are transmitted to the collection server over a standard telephone line, accurate measurements can be immediately and easily retrieved by disease management professionals for analysis and any recommended action.

The device also includes an enhanced flash memory chip, enabling it to store approximately 30 days of collected physiological data. This is a key feature for seamlessly incorporating a home-based monitoring unit into a patient’s lifestyle, providing the freedom to leave the home while daily biometric data variances are recorded. The data can be transmitted when the patient returns home or obtains access to a standard phone line. Several studies verify that patients readily accept tele-home health care because it gives them a greater sense of control and independence, yet it can be done within the privacy of their own homes. The knowledge that routine monitoring visits can be scheduled without clerical assistance reduces anxiety about deteriorating health and feelings of isolation or helplessness. Disease management companies are able to provide a total in-home monitoring solution for less than $20 per enrollee per month.7

Electronic Daily Diary
A tool that is used in many studies is the daily patient diary. This process has been automated with an electronic daily diary software system, which has been made to hook up to patients’ personal home computers. Patients can download the software from the manufacturer’s Web site before entering their readings; however, months of data can be saved in files on the computer once the software is downloaded.

Patients can record their peak flow readings in an electronic daily diary and the program graphs daily readings. Patients can then print out those readings to show their physicians at a later date. This record of peak flow readings and symptoms enables physicians to make important decisions about their patients’ asthma treatments. The daily diary can help patients keep this information so they can share it with their physicians. They can also email the peak flow readings to the physician by saving the file, attaching it to an email, and sending it to the physician’s email address.

Patients should ask their health care provider for help in figuring personal best peak expiratory flow rate. Patients can read their medication instructions for their green, yellow, and red zones on the asthma action plan sticker on the back of the peak flow meter before they begin to track daily peak flow readings.

Patients enter their peak flow reading daily into the electronic daily diary program, which saves the data. They follow their physician’s instructions for taking the medication. To use this program, patients simply follow the following three steps shown on the program page:

Step 1. Set the dates for the peak flow graph using the pull-down menus. The start date can be today’s date or patients can change that date to fill in previous peak flow readings that have been recorded earlier. The ending date could be the date of the next visit to their physician.

Step 2. Enter the personal best rate data as determined by the physician.

Step 3. Select the date for the peak flow reading being entered. Each day, the current date will appear, but the patient can change this date if the reading being entered is from another day in the past. Then, by clicking on the “Make Entry” bar, a window will appear asking the patient to type in the reading and any other symptom or medication notes the patient may want to save. Once everything is typed in, clicking on “OK” will enter the reading. The reading will automatically be plotted on a green, yellow, or red zone graph based on the personal best that was entered. It will also list the reading and notes in the “Diary Listing” section. The “traffic light” will then light up with a zone color and a message will appear below it to alert the patient to the asthma action needed based on the current peak flow reading.8

There is another software system available to the asthma patient that may be used on any desktop computer, Palm OS, or Pocket PC device and can be accessed through any Web browser. The software can plot peak flow readings, drug usage, and nocturnal and exercise-induced asthma so that patients can bring an accurate assessment of their condition to their physician.9

Despite promising results, these new technologies have encountered some resistance. While some internists welcome the influx of home care technologies, others remain skeptical, citing concerns about privacy, impersonal care, and reimbursement issues. Some physicians worry that a patient could make a mistake using the technology and transmit incorrect information. Other physicians fear that if nurses do most of the day-to-day monitoring, physicians will not properly review the data and will lose touch with their patients.

Reimbursement is probably the single largest concern keeping physicians from embracing these types of monitoring technologies. The average cost to the patient for these devices ranges from $40 to $150 with little reimbursement to the patient by health care providers. The physician’s own reimbursement is also an issue. Some systems are sold to the patients or to the physicians but most fee-for-service insurers do not pay physicians for their use of the new technology. Some manufacturers are working to convince payors to reimburse physicians who use their systems and Medicare has begun limited coverage of some devices.10

Kathleen M. Norulak, RRT, RCP, is the owner of Pulmonary Education and Testing Services, a consulting organization in Torrance, Calif.

1. Mannino DC. Surveillance for asthma—United States, 1980-1999. Morb Mortal Wkly Rep MMWR. 2002;51:10-17.
2. US Department of Health and Human Services. Data fact sheet asthma statistics. Public Health Service. 1999:1-4
3. Szalados JE. Telemedicine allows care to reach the farthest outposts. Advance for Managers of Respiratory Care. 2002;5:42-44.
4. Finkelstein J, Cabrera MR, Hripcsak G. Internet-based home asthma telemonitoring—can patients handle the technology? Chest. 2000;117:148-155.
5. Electro Magnetic Solutions. The Doser works in conjunction with your inhaler. Available at: Accessed June 5, 2002.
6. National Asthma Council Australia. Leading the attack against asthma. Available at: Accessed June 5, 2002.
7. Cybernet Medical. MedStar expands capabilities to benefit asthma and chronic obstructive pulmonary disease (COPD) patients. Available at: Accessed June 5, 2002.
8. Respironics Inc. AsthmaMentor electronic daily diary software. Available at: Accessed June 5, 2002.
9. Health Engage. The power of better health. Available at: Accessed June 5, 2002.
10. Palmer I. Products for providing home care remotely. ACP-ASIM Observer (American College of Physicians-American Society of Internal Medicine); July 2001.