New asthma guidelines emphasize control, regular monitoring

Cleveland Clinic Journal of Medicine. 2008 September;75(9):641-653

September 1, 2008|Cleveland Clinic Journal of Medicine

ABSTRACTUpdated asthma care guidelines have recently been released. This review will focus on several elements in the third Expert Panel Report (EPR3) guidelines that reflect substantial differences from recommendations of the second EPR (EPR2) guidelines, issued in 1997 and updated in 2002. A major difference is the emphasis on asthma control. Asthma control can be assessed serially by the use of validated instruments. The goal of asthma therapy is to achieve asthma control by reducing current impairment and future risk. Recommendations for asthma pharmacotherapy have also been revised since the release of the updated EPR2 guidelines. The revisions in asthma management proposed in these guidelines offer the potential for improved asthma care outcomes in the United States.

KEY POINTS

The EPR3 recommends that management decisions be based initially on asthma severity, and subsequently on asthma control as assessed serially by validated tests.
Omalizumab, a monoclonal antibody against immunoglobulin E, is the only adjunctive therapy to demonstrate efficacy when added to high-dose inhaled corticosteroids plus long-acting beta agonists in patients with severe, persistent, allergic asthma.
The EPR3 guidelines recommend consideration of allergen immunotherapy for patients with mild or moderate persistent allergic asthma.

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

Figure 1. The revised paradigm for asthma management recommends that asthma be categorized initially on the basis of severity, with management assigned in an evidence-based manner, but that subsequently, asthma control should be assessed at every clinical encounter, with management decisions based on the level of asthma control.

The revised algorithm for asthma management (Figure 1) recommends that asthma care providers categorize asthma severity at the initial visit (Table 1) and assess asthma control in subsequent visits (Table 2).

How to assess severity

The previous guidelines proposed that asthma severity be assessed before starting long-term therapy. However, many patients are already taking controller medications when initially seen. In the EPR3 guidelines,¹ asthma severity can be inferred on the basis of response or lack of response to drug therapy. Responsiveness is defined as the ease with which asthma control can be achieved by therapy. At the initial visit, severity is assessed on the basis of impairment and risk (Table 1), whether or not the patient is regularly taking controller medication. In assessing impairment, we focus on the present, eg, ascertaining symptom frequency and intensity, functional limitation, lung function, and whether the patient follows the treatment and is satisfied with it.

In assessing risk, we focus on the future, with the aim of preventing exacerbations, minimizing the need for emergency department visits or hospitalizations, reducing the tendency for progressive decline in lung function, and providing the least amount of drug therapy required to maintain control in order to minimize risk of untoward effects. The impairment and risk domains may respond differently to treatment.

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

References

Download Article