Asthma severity: The patient's perspective

Background: Although asthma is a common condition, limited epidemiological data exists on the distribution or course of asthma severity. We know even less about how patients or parents rate the severity of their or their child's asthma or what factors they associate with more severe asthma. A large nationally diverse sample of asthma patients' self-assessment of severity is available but has not been analyzed to look at asthma severity from the patients' perspective. Method: Data from the "household" and "event" files from the 1999 Medical Expenditure Panel Survey were combined to obtain a distribution of patient-reported asthma severity and the health care utilization, medication usage, and personal characteristics associated with different levels of self-reported severity for that subgroup that answered the chronic disease portion of the survey. Results: Almost two thirds of patients (63% of adults) or parents (65% of children) described their or their child's asthma as very or somewhat serious. Among both children and adults, more severe asthma was associated with greater numbers of missed school and workdays, and lower overall health status. The associated differences in health utilization varied by age. Models of severity based on available NAEPP criteria explained less than 10% of the participant's variation in self-reported asthma severity. Conclusion: Parents and patients with asthma appear to use different metrics than physicians and researchers to define the more severe categories of asthma. This disparity suggests the need for an asthma measure that is more widely understood, and accepted by patients and clinicians to serve as a tool to improve asthma-related communications and the achievement of mutually determined therapy goals.