"Previous studies of health care disparities have tended to look at one point in time, but a longer-term picture allows us to see whether disparities are a static or dynamic problem," says Timothy Ferris, MD, of the MGH Institute for Health Policy, the article's lead author. "Our results support the theory that disparities might be greater in the early stages after a technology is introduced and that attempts to reduce disparities might focus on this important period."
In order to track the adoption of inhaled steroid medications for asthma after their introduction in the 1980s, the researchers analyzed data from the National Ambulatory Medical Care Survey from 1989 to 1998. In this annual survey, conducted by the National Center for Health Statistics, physicians complete a form after outpatient visits during a randomly selected week, answering questions about patients' diagnoses and the treatments provided. The researchers identified 3,671 physician visits by patients with asthma during the years studied, determined whether or not inhaled steroids were prescribed or administered during those visits, and also analyzed information on patients' age and race or ethnicity.
During the first two years studied, minority patients were less than half as likely to receive inhaled steroid medications as were non-minority patients. While the overall difference in usage between minority and non-minority patients resolved by the mid-1990s, that change reflected increased usage only among African American patients; the low rate of prescription for Hispanic patients remained virtually unchanged. Children also were significantly less likely than adults to receive inhaled steroid medications throughout the years studied, although there was some increase in usage for the youngest children.
"Technology adoption in health care requires both the doctor to recommend a new agent and the patient to accept it. Many if not most of the steps in that process are not controlled by the patient," Ferris says. "Some factors behind these disparities might be the greater access non-minority patients usually have to specialists, who are more likely to use new technologies, and the higher cost of new medications, which makes them less accessible to the poor and underinsured. Children often do not get access to new technologies because drug manufacturers may not invest in the trials required to demonstrate safety and effectiveness in children. When you put these factors together, it appears that the minority children were the last to benefit from this effective medication."
The researchers also note that there is no way of knowing the correct usage rate for these medications among the various groups. For example, while usage differences between white and black patients seemed to disappear, black patients might still be undertreated, since asthma is more common and often more serious among African Americans. Further studies of factors underlying these and other disparities are being conducted by the Disparities Solutions Center in the MGH Institute for Health Policy.
Co-authors of the study are Karen Kuhlthau, PhD, and James Perrin, MD, of the MGH Center for Child and Adolescent Health Policy; John Ausiello, of the MGH Institute for Health Policy; and Robert Kahn, MD, MPH, Cincinnati Children's Medical Center.
Massachusetts General Hospital, established in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH conducts the largest hospital-based research program in the United States, with an annual research budget of nearly $500 million and major research centers in AIDS, cardiovascular research, cancer, cutaneous biology, medical imaging, neurodegenerative disorders, transplantation biology and photomedicine. In 1994, MGH and Brigham and Women's Hospital joined to form Partners HealthCare System, an integrated health care delivery system comprising the two academic medical centers, specialty and community hospitals, a network of physician groups, and nonacute and home health services.