This review focuses on several elements in the National Asthma Education and Prevention Program’s new guidelines, the third Expert Panel Report (EPR3),1 that differ substantially from those in EPR2,2 issued in 1997 and updated in 2002.3 These differences in approach to the management of asthma described in EPR3 offer a clear potential for reducing the gap between optimal asthma care outcomes as described in guidelines and normative asthma care outcomes in the “real world.”
GREATER EMPHASIS ON CONTROL
The EPR2 guidelines2 recommended that asthma management be carried out in an algorithmic manner. Patients were classified into four severity categories: mild intermittent, mild persistent, moderate persistent, and severe persistent asthma, based on assessment of the level of symptoms (day/night), reliance on “reliever” medication, and lung function at the time of presentation. Pharmacologic management was then assigned according to each respective categorization in an evidence-based fashion.
In an ideal world, this would result in patients with asthma receiving appropriate pharmacotherapeutic agents associated with favorable asthma care outcomes, which were also advantageous from both cost- and risk-benefit standpoints. In the real world, however, this paradigm was flawed, as it relied on accurate categorization of patients in order for pharmacotherapy to be prescribed appropriately. Both providers and patients are prone to underestimate asthma severity,4,5 and for this reason many patients managed on the basis of this paradigm were undertreated.
A new paradigm, based on the assessment of asthma control, has been encouraged in the EPR3 guidelines.1
Severity and control are not synonymous
More than a decade ago, Cockroft and Swystun6 pointed out that asthma control (or lack thereof) is often used inappropriately to define asthma severity: ie, well-controlled asthma is seen as synonymous with mild asthma, and poorly controlled asthma with severe asthma.
Asthma severity can be defined as the intrinsic intensity of the disease process, while asthma control is the degree to which the manifestations of asthma are minimized. Asthma severity is clearly a determinant of asthma control, but its impact is affected by a variety of factors, including but not limited to:
- Whether appropriate medication is prescribed
- Patterns of therapeutic adherence
- The degree to which recommended measures for avoiding for clinically relevant aeroallergens are pursued.
Health care utilization, including hospitalizations and emergency department visits, correlates more closely with asthma control than with asthma severity.7–9 Indeed, a patient with severe persistent asthma who is treated appropriately with multiple “controller” medications and who takes his or her medications and avoids allergens as directed can achieve well-controlled or totally controlled asthma, and is not likely to require hospitalization or emergency department management, to miss school or work, or to experience nocturnal awakening or limitation in routine activities due to asthma. This patient has severe persistent asthma that is well controlled.
In contrast, a patient with mild or moderate persistent asthma who does not receive appropriate instructions for avoiding allergens or taking controller medication regularly or who is poorly adherent will likely have poor asthma control. This patient is more likely to require hospitalization or emergency department management, to miss school or work, and to experience nocturnal awakening or limitation in routine activities due to asthma. This patient has mild persistent asthma that is poorly controlled.
Assess asthma severity in the first visit, and control in subsequent visits
How to assess severity
How to measure control
For all patients with asthma, regardless of severity, the goal is the same: to achieve control by reducing both impairment and risk. Asthma is classified as well controlled, not well controlled, or poorly controlled (Table 2).1