Asthma is a serious chronic lung disease affecting more than 25 million individuals in the United States, most having been diagnosed in childhood (National Heart, Lung, and Blood Institute (NHLBI), 2014). Symptoms include, but are not limited to, shortness of breath, chest tightness, wheezing and cough (NHLBI, 2014). Asthma sufferers can live a normal active life when their asthma is well controlled, however, flare-ups (also referred to as asthma ‘exacerbations’ or asthma ‘attacks’) can occur, causing symptomatic episodes that range in severity (Graham & Eid, 2015). Although asthma is a relatively common disease, the number of hospitalizations, which are often costly, due to exacerbations is unnecessarily high for myriad reasons. These include noncompliance with treatment, lack of knowledge of the disease process, smoking, socioeconomic factors, and exposure to environmental hazards (second hand smoke, mold and other allergens, etc.) (Ramsay, Schwindt, Nguyen, & Margellos-Anast, 2016). Asthma can be challenging to diagnose and manage, however, appropriate prevention at both the primary secondary levels has proven better outcomes for most patients. The purpose of this paper is to discuss the prevention of asthma exacerbations through control of exposure to triggers and management of symptoms.
Asthma is one of the most common non-communicable diseases worldwide. According to the Centers for Disease Control and Prevention (CDC, 2017), asthma affects about 7.8% of people in the United States and the prevalence continues to grow each year. Of those affected, 8.4% are children (<18 years of age) and 7.6% are adults (>18 years of age), with females being affected more often than males [9.1% vs 6.5%] (CDC, 2017). There is an ethnicity factor supporting a higher incidence of asthma in Hispanics of Puerto Rican origin (13.7%) (CDC, 2017). Asthma affects 10.3% of Non-Hispanic Blacks and 7.8% of non-Hispanic Whites are also affected (CDC, 2017). Patients diagnosed with asthma living below the poverty level account for 11.1% (CDC, 2017). Those who are living in urban areas have an increased risk for hospitalization and death (Ramsay et al., 2016). The CDC reports that 1.8 million individuals with asthma are hospitalized and 10.5 million visit a physician’s office per year (McCracken, Veeranki, Ameredes, & Calhoun, 2017). The risk of hospitalization increases when asthma is poorly controlled and can cause significant financial, emotional, and physical burdens on both patients and families, thus emphasizing the importance of managing the severity and frequency of asthma exacerbations (Graham et al., 2015).
The term “asthma” originates from an ancient Greek word aazein, which means “to pant” (Alhassan, Hattab, Bajwa, Bihler, & Singh, 2016). Asthma is a disease that affects the patient’s airway. When poorly controlled, asthma results in acute episodes of progressively worsening symptoms that include, but are not limited to: shortness of breath, chest tightness, air hunger, and wheezing (McCracken et al., 2017). These symptoms are associated with variable expiratory airflow resulting in narrowing of the airway, increased mucus production, and therefore difficulty breathing (Durham, Fowler, Smith, & Sterrett, 2017). In the event of an asthma flare up, early recognition is key to successful outcomes. Fortunately, when asthma is effectively managed, it is possible for asthmatics to live normal active lives.
Identifying and avoiding triggers, as well as improving current control of symptoms will decrease the frequency and severity of future asthma attacks and are key to increasing quality of life (Graham et al., 2015). Triggers include: indoor/outdoor allergens, weather, infections, air pollution, drugs, occupational exposures, stress and emotional disturbances, and food (Gautier & Charpin, 2017). Triggers should be avoided at all cost; however, it is nearly impossible to completely avoid them without interfering with daily life.
Current research shows ecological factors at several different levels impact outcomes and include: an individual’s knowledge about the disease, self-management skills, psychological state (e.g. depression), etc. (Mosnaim et al., 2017). Certain factors place patients with asthma at an increased risk for experiencing an asthma flare up and include: smoking, viral infections, and vitamin D deficiency. Patients with asthma who suffer from viral infections of the respiratory tract are at an increased risk for exacerbations (Graham et al., 2015). Chlamydia pneumoniae (CP) and other viral, bacterial and fungal microorganisms are thought to be responsible for exacerbations in chronic asthmatics (Webley & Hahn, 2017). It is recommended asthmatics receive routine vaccines to limit the chance of illness which leads to asthma flare ups. Smoking is another risk factor for asthma flare ups and although patients are aware of this, they continue to smoke regardless. Graham et al. (2015), reports that of the adults presenting to the emergency department with acute asthma symptoms, 35% admitted to being smokers. Evidence suggests vitamin D deficiency is associated with higher incidence of asthma symptoms due to lack of sunlight and more time spent indoors (Sears, 2014).
At least 40% of asthma patients report they are symptomatic and experience exacerbations (Graham & Eid, 2015). In the US alone, asthma is responsible for thousands of deaths each year (Mosnaim, Akkoyun, Eng, & Shalowitz, 2017). When asthma is poorly controlled it can have a considerable impact on day to day life for patients and can interfere with work, school, and daily activities. Frequent hospitalization’s as well as uncontrolled symptoms result in feelings of decreased health perception and quality of life for the patient (Sullivan, Smith, Ghushchyan, Globe, Lin, & Globe, 2013). Despite current guidelines for the treatment and management of asthma, it continues to be underdiagnosed and poorly managed for a number of reasons, resulting in poor outcomes (Lai-Yan et al., 2017).
Identification (Case Finding/Screening)
Diagnosing asthma is not a facilitated process and includes multiple steps to rule out other potential diagnoses. According to José, Camargos, Cruz Filho, & Corrêa (2014), over diagnosing and underdiagnosing asthma is correlated to diagnostic errors and account for 54% of under diagnosed, and 34% of over diagnosed asthma patients. Accurate history, thorough physical examination, and assessing lung function through spirometry in the primary care setting are all key components to a successful diagnosis, although, not all people with asthma will present with asthma like symptoms, thus making an accurate diagnosis difficult (McCracken et al., 2017). Distinguishing between asthma and COPD in people who smoke and older adults can present additional challenges in diagnosis (McCracken et al., 2017). Wheezing, cough, chest tightness, and dyspnea are all suggestive of a flare up, however, these symptoms may only be present during times of exertion, upper respiratory tract infections, and seasonal allergies making diagnosis challenging at times (McCracken et al., 2017).
There are multiple diagnostic and screening tools used to identify asthma. One of the screening tools is the Asthma Control Test (ACT), which assists providers in determining how well an individual’s asthma is controlled and should be assessed at every visit (American Thoracic Society (ATS), 2016). ACT is a self-administered tool for individuals 12 years of age and older consisting of 5 questions (ATS, 2016). If the patient scores less than 19, it is assumed that the individual’s asthma is not well controlled; a score of less than 15 indicates very poorly controlled asthma (ATS, 2016). One of the advantages of ACTs is that they are efficient and non-invasive, and patients are likely to partake.
A detailed past medical history should be obtained from the patient including any and all symptoms prior to the visit. As with any chronic disease, a thorough family history should also be discussed during the visit especially when the potential for asthma diagnosis is present. Physical findings may not be as obvious in patients who present with well controlled asthma who are in a healthy state (McCracken et al., 2017). Typical symptoms of an individual exhibiting an asthma exacerbation include: auscultatory wheezing, tachypnea, tachycardia, cyanosis, and accessory muscle use. Recognizing patients in acute distress and initiating treatment early are crucial in the prevention of worsening symptoms and even death.
The US National Asthma Education and Prevention Program (NAEPP) established guidelines in 1989 to raise awareness for asthma and ensure appropriate diagnosis and management through consultation with federal agencies and healthcare organizations (NHBLI, 2014). NAEPP developed an approach that categorizes asthma based on severity: intermittent or persistent (mild, moderate, or severe) (NHLBI, 2014). Classifying the severity of asthma depends on two areas of concern: impairment and risk (Global Initiative for Asthma (GINA), 2017). The area of impairment consist of measured airway obstruction, frequency and intensity of daytime and nocturnal symptom relief, and interference of daily activities due to symptoms, whereas risk assesses frequency of acute episodes (McCracken et al., 2017).
Spirometry is an effective diagnostic procedure that should be performed in patients with symptoms consistent with asthma (Heijkenskjöld-Rentzhog, Janson, Berglund, Borres, Nordvall, Alving, & Malinovschi, 2017). Spirometry measures airway obstruction and its reversibility by measuring the maximum volume forcibly exhaled (FVC) vs the volume of air exhaled during the first second of the procedure (FEV1), and comparing the two (FVC:FEV1) (McCracken et al., 2017). Normal FVC:FEV1 ratio in adults is 0.7-0.8 and airway obstruction is suspected if the FEV1:FVC ratio is less than the normal limit (McCracken et al., 2017). If airway obstruction is present, the next step is to assess reversibility response with administration of a bronchodilator (McCracken et al., 2017). An increase in FEV1 of 200 mL or greater and a 12% or greater increase from baseline after administration of the inhaled short acting beta2-agonist can confirm reversibility of airway obstruction (McCracken et al., 2017). However, if the FEV1 response is less than 200 mL or less than12% from baseline (indicating fixed or partial obstruction), an alternative diagnosis or severe asthma should be considered (McCracken et al., 2017). If the initial FEV1:FVC ratio is greater than the lower limit of normal and asthma is suspected, then a methacholine challenge test can be useful for diagnosis and is especially helpful in diagnosing difficult patients or patients are unable to perform the forced expiratory maneuver, such as the very young and elderly (Mochizuki, Hirai, & Tabata, 2012).
Chest radiograph and computed tomography (CT) are not necessarily helpful in diagnosing asthma, however they can exclude other potential diagnoses such as emphysema, lung cancer, infiltrative disease, and pneumonia (McCracken et al., 2017). A complete blood count (CBC) is useful in assessing the presence of eosinophilia and can guide therapy selection in certain cases (McCracken et al., 2017). Serum total IgE, skin prick testing, and fractional excretion of nitric oxide are additional modalities useful for diagnosing asthma (McCracken et al., 2017).
As with any other disease, the goal of interventions is to reduce the severity of symptoms or prevent their occurrence altogether. In the case of asthma, symptom reduction can provide a level of homeostasis and quality of life, even allowing some patients to live a seemingly normal and active life. Utilization of Asthma Action Plans (AAPs) to increase self-management, decreasing the likelihood of indoor allergens, avoiding active and passive smoking, and adhering to medication regimens are interventions to decrease the likelihood of flare ups (Gautier & Charpin, 2017). Other means of controlling symptoms are getting routine vaccinations, avoiding pests, mold, pets, and outdoor allergens such as air pollution and changes in weather (Gautier & Charpin, 2017).
The NAEPP guidelines recommend the use of individualized Asthma Action Plans (AAPs) to help patients better control their asthma (Akhter, Monkman, Vang, & Pfeiffer, 2017). The goal of AAPs is to provide patients with written steps as a guide to properly manage asthma (Akhter et al., 2017). Improving patient’s awareness of the disease, self-care, and control over asthma flare ups through the utilization of AAPs have resulted in fewer days missed at school, fewer acute episodes, and lower ACT scores (Akhter et al., 2017). Although evidence based research shows improved asthma control with AAPs, AAPs are severely underutilized in the US (Akhter et al., 2017).
A form of primary prevention consists of smoking cessation intervention and avoiding second hand smoke. People with asthma who smoke have a higher incidence of hospitalizations than do nonsmokers and should therefore be educated on the importance of smoking cessation in the clinical setting as well as upon discharge from the hospital (Gautier & Charpin, 2017). According to a study done by Weaver et al. (2012), 87.3% of respondents with at least one preexisting medical condition were asked to self-report about tobacco usage. Of those 87.3% of respondents, only 66% were given verbal instruction to quit with resources such as medication and counseling (Keith et al., 2017). Healthcare providers must do a better job at inquiring about smoking habits and offering advice or treatment for smoking cessation. In addition to smoking, efforts to decrease unnecessary breathing problems in asthmatics from second hand smoke through no-smoking policies have been implemented (Young et al., 2016).
Additional interventions at the primary level include simplistic means of reducing indoor allergen exposure using high efficiency particulate air filters (HEPA). This filter is used to rid circulating air of pollen, dust mites, and other allergens, leading to a purified and allergen free environment. The use of a humidifier/dehumidifier in conjunction with a hydrometer is useful to keep air moisture levels at a consistent level of 40% or less as recommended (Dighton, 2016). Another suggestion for a healthier home environment includes having your air conditioning unit professionally cleaned prior to using it each year and changing the filters each month (Dighton, 2016).
A major barrier to the interventions mentioned above is cost. Implementing things such as HEPA filters or high efficiency vacuum filtering systems can be costly. Issues surrounding medications are also a barrier and include medication adherence along with proper use of the medication and remembering to administer it (Miles, Arden-Close, Thomas, Bruton, Yardley, Hankins, & Kirby, 2017). Lack of education on asthma and how to manage it are reported barriers for everyone involved from healthcare workers to patients to caregivers (Miles et al., 2017).
Health Behavior Theory/Model
The overall goal of controlling asthma should include symptom reduction through proper education in an effort to reduce the possibility of future exacerbation. One way of achieving this is through programs aimed at providing adequate knowledge and understanding of the disease so that people with asthma can achieve better self-care.
Helping Chicago’s Westside Adults Breathe and Thrive (HCWABT) is a program aimed at addressing the critical knowledge gap and improving health behaviors in adults with poorly controlled asthma living in Chicago’s urban, impoverished Westside (Ramsay, Schwindt, Nguyen, & Margellos-Anast, 2016). HCWABT is a 12-month program consisting of 6 home visits per year performed by Community Health Workers (CHW) [at 2 weeks, 3 months, 6 months, 9 months, and 12 months post-baseline]. The Social Cognitive Theory (SCT) is the basis of the learning that occurs at each home visit (Ramsay et al., 2016). The SCT suggest that individuals learn by observing others through social interactions and experiences (Pender, Murdaugh, & Parsons, 2015). During these 2-hour home visits, the CHW provide asthma education as well as refer those individuals with other medical concerns such as chronic disease or mental illness (Ramsay et al., 2016). Participants in the program are taught about asthma pathophysiology, symptoms and symptom recognition, triggers, purpose of quick-relief and controller medications, correct use of medications and devices, and proper use of an Asthma Action Plan (Ramsay et al., 2016). CHWs verify that the participant understands how to properly administer their medications based on correct return demonstration as well as provide educational material to reinforce learning (Ramsay et al., 2016).
During these home visits CHW conducted environmental assessments to identify possible triggers while also teaching about trigger reduction strategies (Ramsay et al., 2016). At the end of each home visit CHWs assist participants based on the Transtheoretical Model (TTM) by setting goals, recognizing barriers, and assessing participant confidence as relates to the attainment of established goals (Ramsay et al., 2016).
Challenges to the program included: difficulty contacting individuals, participant retention for the duration of the program, lack of smoking cessation services due to costs, affordable rehab services for mental health and drug abuse, wait times, overlapping COPD diagnosis, and housing instability for participants. Having money for things such as food, rent, and bills was rated a higher priority than health care needs among participants (Ramsay et al., 2016).
Research demonstrates behavioral modification techniques represent one category of strategies used to increase compliance to asthma treatment plans in order gain control of symptoms (Farooqui, Phillips, Barrett, & Stukus, 2015). Evidence shows the HCWABT program yields positive outcomes in individuals with asthma living in urban, poor, minority communities (Ramsay et al., 2016). CHWs played a significant role in the program by building trust with the participants, therefore resulting in increased receptiveness and motivation to improve the participants overall health and well-being (Ramsay et al., 2016).
Although current research exists on the causes of asthma and how to prevent it, there continues to be an increase in prevalence. According to the World Health Organization (WHO) (2017), Asthma is under-diagnosed and under-treated, affecting individuals and families both financially as well as regards the quality of their lives. The main focus of preventing asthma exacerbations remains on a correct diagnosis, adhering to medication regimens and avoiding triggers. A multitude of factors can influence asthma symptoms and must be recognized so that intervention can occur to prevent future exacerbations. Unfortunately, asthma is not a curable disease, though when asthma control is achieved, individuals are able to live relatively normal lives with little to no restrictions on activities.
Diagnosing can be challenging and frustrating for healthcare providers as well as for people with variable symptoms characteristic of asthma. One of the challenges is differentiating asthma from other chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD) and respiratory infections causing similar symptoms. It is extremely important that healthcare providers have a thorough understanding of the disease so that misdiagnosis does not occur. New methods in making diagnosing asthma more streamline and accurate would be beneficial for both providers and patients. In addition to the needs mentioned above, effective and affordable medication is essential to improving outcomes among asthmatics, especially in the low-income populations where the prevalence of asthma is highest. The WHO (2017), reports that low and lower-middle income countries attribute to over 80% of asthma related deaths.
The importance of preventing asthma exacerbations through control is a multifaceted approach and involves many different factors. It is estimated that in the next 10 years deaths attributed to asthma will increase if proper prevention and intervention is not implemented (WHO, 2017). Unnecessary asthma exacerbations are preventable through proper prevention at the primary and secondary levels.
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Community and Published Resources
Allergy and Asthma Network: http://www.allergyasthmanetwork.org/patients/
American Lung Association: http://www.lung.org/support-and-community/
Asthma and Allergy Foundation of America: http://www.aafa.org/
Food Allergy Research and Education: https://www.foodallergy.org/
Centers for Disease Control and Prevention: https://www.cdc.gov/asthma/default.htm
American Academy of Allergy, Asthma, and Immunology: http://www.aaaai.org/home
Air Now: https://airnow.gov/
United States Environmental Protection Agency: https://www.epa.gov/asthma
National Heart, Lung, and Blood Institute: https://www.nhlbi.nih.gov/
Asthma Community Network: http://www.asthmacommunitynetwork.org/
Smoke Free offers help on smoking cessation: https://smokefree.gov/
Asthma in Missouri: http://health.mo.gov/living/healthcondiseases/chronic/asthma/pdf/MO.pdf
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