ASTHMA
September 30, 2015

Managing Asthma

Cathy G. Benninger, RN, MS, CNP and Jennifer W. McCallister, MD, FACP, FCCP
Asthma's symptoms and severity can change, so management is an ongoing process.

Ms. Benninger is a staff member and Dr. McCallister is Associate Professor of Internal Medicine, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, The Ohio State University Wexner Medical Center, Columbus, OH.



There are about 24.6 million people who report a diagnosis of asthma in the United States. They represent about 8% of adults and almost 10% of children [1] (references at end). The direct and indirect costs of asthma in the U.S. have been estimated to be $18 billion, contributing significantly to the expanding healthcare financial burden [2].

These high costs have a lot to do with poor asthma control, which leads to increased asthma-related mortality, and increased healthcare use with more frequent use of emergency departments and hospitalizations for care [2, 3].

A systematic approach to asthma care controls the disease in the majority of patients.

There are evidence-based guidelines to help guide healthcare providers manage asthma patients' symptoms [3, 4]. This sort of systematic approach to asthma care controls the disease in the majority of patients [5], and results in improved health-related quality of life, regardless of asthma severity [6].

Unfortunately, too often the guidelines are not fully used [7, 8]. If you have asthma, you will probably want to know what the guidelines say and what the pitfalls related to asthma control are.

Overview of NAEPP Guidelines

After the diagnosis of asthma is established, the The National Asthma Education and Prevention Program (NAEPP) guidelines [3] recommend a stepwise approach for the treatment of asthma based on the level of asthma severity (for initiation of therapy) or degree of control (for adjustments in therapy).

Therapy is increased (stepped up) when control is inadequate, and decreased (stepped down) whenever possible to achieve the minimum level of medication necessary to maintain control, minimize side effects and cost.

The better a person with asthma learns to monitor for inadequate control with either symptom or peak expiratory flow rate monitoring, the better his or her control will be.

The guidelines provide recommendations for long-term management of asthma with an emphasis on four key components of care: assessment and monitoring, education, control of environmental factors and co-morbid conditions, and medication selection and use.

Assessment and Monitoring

The most important first step to maintaining long-term control of asthma is frequent monitoring. The better a person with asthma learns to monitor for inadequate control with either symptom or peak expiratory flow rate monitoring, the better his or her control will be. The “Rules of Two®” [10] is a useful way to learn asthma control self-assessment.

Rules of Two®

Do You:
  • Have asthma symptoms or take your quick-relief inhaler more than Two times a week?
  • Awaken at night with asthma symptoms more than Two times a month?
  • Refill your quick-relief inhaler more than Two times a year?
  • Measure your peak flow at less than than Two times 10 (20%) with asthma symptoms?

  • If you answered “yes” to any of these questions, current guidelines suggest you talk with your physician.

    (Adapted from: Rules of Two® (www.baylorhealth.com) [10])

    Daily peak flow monitoring is helpful for patients with moderate to severe disease, those with prior history of severe flare-ups, and in patients who don't perceive airflow obstruction as accurately [3]. This is also helpful for people with asthma who also have vocal cord dysfunction (VCD). The use of a peak flow can help these individuals distinguish between shortness of breath from asthma, since expiratory flows are rarely affected by vocal cord spasm [11].

    Not So Well-Controlled
    People with asthma tend to think they have better control over their symptoms than they do. Large surveys have demonstrated that patients are poor at assessing their own level of asthma control, with many overestimating their degree of control when self-reported symptoms are correlated with guideline-based determinations [8].

    In one study, 71% of asthmatics reported they were controlled or well-controlled, but in reality only 29% were categorized as such by the NAEPP parameters. The reasons for patients’ poor awareness of inadequate control have been difficult to characterize, and do not seem to be specific to any unique patient characteristics or management strategies [12].

    And it's not just patients. Physicians also sometimes overestimate asthma control [13, 14]. There are tools [15, 16, 17] that can be used to assess control during office visits, rather than relying solely on a person's self-reported symptoms and open ended questions. Your doctor may also want to review your symptom diary and ask questions regarding asthma impact on activity, sleep, work or school and frequency of use of short-acting beta-agonists [3].

    Physicians also sometimes overestimate asthma control.

    In some patients asthma symptoms do not correlate well with the degree of airflow obstruction [18], so evaluation of lung function should be used in combination with other measures. In the doctor's office, spirometry is the preferred objective measure of airflow obstruction [3], especially in those who are poor perceivers of symptoms and may not easily recognize inadequate control or worsening asthma [12]. Current guidelines recommend spirometry assessment at least every one to two years, with more frequent evaluation in patients with poorly controlled disease [3].

    Measurement of fractional exhaled nitric oxide (FeNO) may serve as an additional diagnostic tool for the identification of eosinophilic airway inflammation and inadequately controlled asthma in some patients [19]. FeNO may be useful in determining the need for inhaled corticosteroids (ICS) and monitoring response or compliance with therapies. However, limitations in its wide applicability exist, including the lack of reimbursement from some insurers.

    Education Is The Best Protection

    When patients know more about managing their asthma it improves their medication adherence [20], asthma control [21] and quality of life. It also reduces hospitalizations, emergency department visits, unscheduled provider visits and lost work days due to asthma [22].

    The best way to become better at asthma self-management is to become more actively engaged in your own care [23, 24, 25]. Your doctor will implement a treatment plan which is based on what appears to be the severity and triggers for your asthma, and identify co-morbid conditions.

    What you can do to better control your asthma is become more educated about your own, individual, symptoms and learn about:

  • The action of the medications you take
  • The right way to use the inhalers, spacers and nebulizers you may have
  • The difference between control versus relief therapy
  • The common asthma triggers and avoidance measures
  • Signs and symptoms of inadequate asthma control
  • The right way to self-treat various asthma symptoms
  • When you should seek medical care
  • The best ways to manage other co-morbid conditions
  • Importance of regular follow-up

  • We'll discuss some of these topics below.

    Common Asthma Triggers

    Knowing what triggers your asthma is the cornerstone of asthma management. Not only will you want to have a discussion with your doctor about what may be triggering your asthma, but you should ask for advice about ways to avoid or eliminate triggers [30, 31, 32].

    Colds and Flu
    Upper respiratory infections caused by viruses are a common cause of asthma flare-ups [33, 34, 35]. The best way to prevent them is to get immunized, wash your hands often, especially during cold and flu season; and avoid those who are ill.

    Given the serious consequences respiratory infections can have for those with asthma, getting vaccinated is one of the best steps you can take to protect yourself.

    Patients with asthma are at increased risk for complications from influenza. Everyone over six months of age without contraindications should be immunized [36]. Inactivated influenza vaccines are recommended instead of live attenuated influenza vaccines because these have been linked to asthma flare-ups in some patients [37]. The risk of pneumonias in people with asthma is less clear [38, 39], but the Centers for Disease Control and Prevention (CDC) recommends vaccination with the pneumococcal polysaccharide vaccine (PPSV23) in all adults age 65 or older and in adults age 19 and over who have asthma or who smoke [36].

    Unfortunately, vaccination rates for adult asthmatics remain low, hovering at about 36 percent [40, 41, 42]. Given the serious consequences respiratory infections can have for those with asthma, getting vaccinated is one of the best steps you can take to protect yourself.

    Smoking and Other Triggers
    It is estimated that between 24 and 35% of asthmatics smoke, and second-hand tobacco smoke exposure is pervasive among non-smokers [43, 44, 45]. Direct and significant indirect exposure to tobacco smoke is associated with more frequent and more severe asthma attacks [43, 46], lower lung function, greater rescue inhaler use [46] and absenteeism from work [47, 48].

    The increase in smoke-free public areas has been associated with declines in asthma-related emergency department (ED) admissions and hospitalizations [49, 50].

    Other asthma triggers include exercise [3], sensitivity to sulfites, stress [51], weather (especially high humidity [52], cold or dry air [53]), air pollution (particularly long-term exposure to traffic-related pollution) [54], occupational exposures, as well as medications (beta-blockers [55] and aspirin products [56, 57, 58]).

    The use of beta-adrenergic blockers has been avoided or limited in asthmatics due to the potential risk of bronchospasm. Beta-blockers can be prescribed for mild to moderate asthmatics with minimal respiratory effect and may be considered in asthmatic patients with concomitant cardiovascular conditions calling for the use of such agents for management [55].

    Co-morbid Conditions
    There are several conditions that frequently occur with asthma and can complicate a person's condition. It's important to identify and aggressively manage these co-morbid conditions known to exacerbate asthma. Sinusitis and gastroesophageal reflux disease (GERD) are both associated with more severe disease [59]. An increased body mass index (BMI), lack of asthma control and respiratory tract infections are associated with increased risk of an exacerbation.

    Allergies
    Allergic rhinitis contributes significantly to asthma attacks visits to emergency rooms [59, 60, 61, 62, 63, 64]. This is why, if you have allergies, you should get tested to determine the specific allergens exacerbating your asthma. This not only helps guide therapy, but also avoidance measures [61]. Once the allergen(s) have been confirmed, targeted avoidance measures can be instituted but general avoidance measures in those with non-confirmed allergies are not recommended [65].

    Obesity
    There is a 3.5 times higher incidence of asthma among middle-aged, never-smokers who have a BMI greater than 35, compared to normal weight individuals [66, 67]. A five-pound weight gain over one year has been associated with poorer asthma control and greater need for oral corticosteroids [68]. Additionally, obesity has been associated with reduced responsiveness to inhaled corticosteroids [69, 70], which may contribute to more asthma related symptoms.

    Weight-loss may be a strategy for improving asthma control in obese patients [71, 72] but a recent review of four published studies failed to demonstrate weight-loss as a specific intervention for asthma control [73]. Even so, while additional well-designed studies are needed to support weight-loss as a specific measure to improve asthma control, the potential added benefits of weight reduction on other co-morbid conditions should not be underestimated.

    Weight can also affect sleep. Overall, asthmatics tend to have poorer sleep quality than non-asthmatics [74], but those with co-morbid sleep apnea or those who are at high risk of sleep apnea report more daytime and nighttime asthma symptoms and experience greater difficulty controlling their asthma [75, 76, 77].

    Gastroesophageal Reflux Disease
    The relationship between asthma control and GERD is not so clear. Asthma patients with GERD report more asthma symptoms and lower quality of life, but there is no physiological difference in lung function, nocturnal awakenings or short-acting bronchodilator when they are compared to asthmatic patients without GERD [78].

    In double-blind trial of inadequately controlled asthmatics, the presence of asymptomatic GERD was common but treatment with proton pump inhibitors did not improve asthma control [79]. However, in another study of asthmatics with GERD, treatment with esomeprazole 40 mg twice a day improved FEV1 and quality of life scores [80]. Additionally, asthmatic patients with severe GERD may be helped by a procedure in which the lower esophageal sphincter is reinforced to prevent reflux [81]. GERD is common in asthmatics but support is lacking for empirically treating those with asthma without the presence of GERD symptoms.

    Medications and Keeping Up Treatment

    It makes sense that taking your medication — medication adherence — improves asthma control and can reduce the frequency and severity of asthma flare-ups [82]. Overall, asthma patients' adherence to their prescribed asthma medication regimens is estimated to range between 30-70% [83, 84].

    In one study, only 49% of participating asthmatics filled initial prescriptions for an asthma controller therapy and only 18% obtained more than two refills [85]. Just as worrisome is that in those participants who filled prescriptions for short-acting beta-agonists, 23% refilled the prescription more than four times in one year indicating poor asthma control.

    Those with difficulty remembering doses may respond to cues such as setting cell phone reminder alarms or placing medications by routinely used items in the home such as tooth brushes, coffee pots, or chargers for electronic devices.

    The cost of medications, concerns about therapies, difficulties with access to care, or misunderstandings about prescribed regimens are all barriers to keeping up a medication regimen [88]. In addition, patients may decide to change their medication or dosage based on the opinions of nonmedical professionals such as friends and family, or based on how safe or unsafe they believe their medications to be, or medication-related side effects [89], cost [90] or simple forgetfulness [84].

    As mentioned earlier, proper education and a better understanding of the mechanism of action of the medication and the reason for its use may be helpful when it comes to getting asthmatics to comply with treatment.

    Forgetfulness and Concerns About Cost
    Those with difficulty remembering doses may respond to cues such as setting cell phone reminder alarms or placing medications by routinely used items in the home such as tooth brushes, coffee pots, or chargers for electronic devices [91]. Medication-related side effects are usually easily remedied by changing formulations, delivery devices or adding a valved holding chamber also known as a spacer to metered dose inhalers to slow the delivery of the medication in order to lessen deposit in the upper airway.

    The cost of medications is a significant challenge to prescribers and patients alike. Increases in monthly co-pays of more than five dollars have been associated with reductions in asthma medication use, with the result being more unscheduled office and emergency room visits for uncontrolled asthma [90].

    The uninsured are four times less likely to fill prescriptions for asthma than those who are insured [1]. For the uninsured and those with gaps in insurance coverage or high co-pays, there are discount programs offered by various organizations or pharmaceutical manufacturers that can be explored.

    Medication-related side effects are usually easily remedied by changing formulations.

    Inhaler Mistakes
    Unintentional non-adherence may simply be the result of poor inhaler technique [92, 93, 94], inadequate knowledge regarding the action and use of the medication [1, 95] or complicated and poorly understood medication regimens [84]. Current inhalers require complex coordinated motor skills for accurate delivery of the medication dependent upon physical manipulation of the device, coordinated deep breath with actuation, if using metered dose inhalers (MDI) [96], or sustained adequate inspiratory flow for powder dose inhalers (PDI) [97].

    Misuse of inhalers is common and has been associated with older age, lack of instruction by a health care provider [96] and lower education [93]. Critical errors in the use of MDI occur in 12-71% of users [93, 96], and commonly involve not breathing out before actuating the device [93] or poor coordination in actuating the inhaler at the start of inhalation [96].

    Among users of three different PDI inhalers, 35-44% were observed to have critical errors with the most common being stopping inhalation of the medication prematurely [93]. Patient education and inhaler instruction improves accuracy but competency has not been found to be maintained over time, requiring regular review and reinstruction [94]. Some patients may continue to make critical mistakes requiring a change in their inhaler delivery devices [92].

    Conclusion

    Asthma is a highly variable condition and changes in most individuals over time [3, 9]. The process of monitoring and assessment of control with appropriate adjustments in therapy, review of medication adherence and technique, and management of triggers and co-morbidities should be an ongoing aspect of treatment.

    If you have asthma, self-management should be seen as a never-ending interactive process requiring reassessment, education, and reinforcement at each follow-up visit with your doctor [3, 84]. The ultimate goals of successful asthma management are to reduce impairment by limiting symptoms and impact on quality of life, and to minimize risk by preventing exacerbations, loss of lung function and adverse effects from asthma therapy [3].

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