Pulmonary Disorders: Asthma
Assessment and Classification of Asthma for LEO Impairment Assessment
Assessment of impairment and risk of sudden incapacitation of LEOs with asthma presents several problems. By the prevailing clinically-applied definition as of early 2017, asthma is a disorder of episodic airflow obstruction with underlying irritability of airways associated with degrees of inflammation.3,4 Additionally, the severity of episodes is variable, even in persons who have rare episodes.3 At the same time, evidence supports that, with good compliance to a treatment program based on maximizing pharmacologic therapy, a majority of adults with asthma can be controlled to a low risk of exacerbation, minimal subjective impairment and normal to minimally reduced pulmonary functional capacity between exacerbations.10 No trials have been published, however, correlating functional physical exertion impairment objectively to any of the criteria used to assess degree of severity or control in asthma.
Despite the difficulty with objectively assessing either functional impairment or risk of impairing exacerbation, the American Thoracic Society (ATS) has commented that there is little available research to support restricting persons with “appropriately treated” asthma from participation in recreational activities in which the danger of the activity to the person with asthma or to others would be compounded by an asthma exacerbation.14 This statement by the ATS specifically addresses SCUBA diving. The ATS comments further that guidance on participation in dangerous activities is consensus-based without research evidence.
The National Heart Blood and Lung Institute (NHBLI) 2007 Expert Panel Report 3 (EPR-3): Guidelines for the Diagnosis and Management of Asthma and the 2018 GINA report, both evidence-based reviews and guides for assessment and clinical management of asthma, offer criteria for assessing the degree of control of asthma in persons receiving treatment. These guidelines are based on a combination of subjective report, objective assessment of lung function, and medical history. Guidelines from ATS, the American Medical Association, and Social Security for assessing impairment and disability from asthma also offer methodologies based on a combination of subjective report and objective evaluations.15,16,17
Since much of the information upon which assessments are made in these guides is subjective, there are no means of verification. No studies directly relating the EPR-3 categories of control with physical effort ability or impairment were identified for this review. Each category includes elements of patient self-assessment of impairment.
Although all four of the above-cited assessment methods use FEV1 as a characteristic for classifying severity of disease, degree of control or degree of impairment, there is no published data directly relating FEV1 to exercise capacity. Studies of patients with COPD have demonstrated a loose relationship, but with a very wide variability among subjects, likely related to underlying degrees of physical fitness.18
The current discussion of assessment is founded on the presumption that the police physician is not making primary diagnoses of asthma, but, rather, is evaluating persons who already have an established diagnosis of asthma. The foundations for the diagnosis should be verified by the police physician through review of medical records. It is to be expected that there will be situations in which the police physician will call into question the diagnosis.
Clinical assessment of asthma per EPR-3 has two components, both of which affect ability to safely and effectively perform essential LEO job functions:
- current level of impairment and
- risk of future exacerbations.
Although the frequency of acute episodes of bronchospasm events and the FEV1 can be used to predict overall likelihood of more such events, they do not help predict actual timing or severity of such events.3,19 Even persons with infrequent episodes of bronchospasm may have severe episodes.3
EPR-3 recommends evaluating persons under treatment for asthma for the level of control, differentiating well-controlled, not-well-controlled and very poorly controlled. Current level of impairment is primarily based on direct interrogation in four subjective dimensions over the most recent 2 to at maximum, 4 weeks, due to degradation of recall over greater time:
- Night-time awakening;
- Interference with normal activity;
- Short-acting beta2-agonist use for symptom control other than exercise-induced bronchospasm (EIB).
EPR-3 recommends that impairment assessment incorporate one of four recommended validated asthma assessment and monitoring instruments (see Table 2). These have not been focused on in these guidelines for evaluation of LEOs since they largely repeat the subjective dimensions noted above, thus making them subject to significant risk of employment-fear bias.
In addition to obtaining a direct history from the person undergoing what is essentially a fitness for duty evaluation, review of medical records is critical to obtaining as much objective information as possible for assessment of both impairment and risk. In order to have a robust understanding of the stability and control of a person’s asthma, the Task Group recommends review of medical records for the preceding 3 years or since diagnosis, if less than 3 years.
EPR-3 recommends that either FEV1 or Peak Expiratory Flow (PEF) be used for objective assessment of pulmonary function. However, peak expiratory flow is considered significantly inferior to formal spirometry testing for FEV1.20 Thus it seems more appropriate to use FEV1 for any objective assessment of LEO pulmonary function remembering that there is no literature directly correlating FEV1 to ability to perform any sort of physical activity, including essential law enforcement job functions.
EPR-3 recommends basing assessment of the risk for future exacerbations on the number of episodes of exacerbation for which oral systemic steroids were prescribed over the year prior to evaluation. The prediction is for risk of experiencing an exacerbation requiring hospital care or systemic oral steroids over the ensuing year. This is of little help in forming a categorical assessment of risk of inability to safely and effectively perform essential LEO job functions.
Based on these evaluation criteria, persons can be classified into three groups: 1) well-controlled; 2) not-well-controlled; and 3) very poorly controlled. Despite the criticism that this 3-tiered system of classification is too simplified for optimizing treatment among the increasing number of phenotypes being defined, it reflects a person’s functional status and risk in a manner that matches concepts of assessing fitness-for-duty.
Initial evaluation and follow-up evaluations should include physical examination of not only the lungs, but also the cardiovascular and muscular systems. Initial and general follow-up evaluations by the police physician generally will not require performance of comprehensive pulmonary function testing. This may be necessary in some cases, though, to differentiate pulmonary from other causes of inability to perform essential job functions. Additionally, the police physician should always remember that there are other disorders that may mimic asthma and be attentive to a possible misdiagnosis, particularly in persons who report difficulty gaining control of symptoms attributed to asthma or with unusual circumstances.
Some Asthma Mimics in Adults
- COPD (e.g., chronic bronchitis or emphysema)
- Vocal cord dysfunction
- Medication-induced cough (e.g., angiotensin-converting enzyme (ACE) inhibitors)
- Eosinophilic pulmonary infiltration
- Pulmonary embolism
- Mechanical airway obstruction (e.g., tumors)
- Congestive heart failure
Evaluation of LEOs with asthma should allow for categorizing the LEO into one of three categories: well-controlled, not-well-controlled and poorly controlled (simplified from EPR-3 “very poorly controlled”).
For the purposes of this discussion concerning evaluations for performance of essential law enforcement duties, well-controlled asthma is defined as meeting all of the following EPR-3 criteria:
- Based on a personal report and/or documented evidence over the 4 weeks prior to evaluation of:
- Symptoms on no more than 2 days per week
- Nighttime awakening from bronchospasm no more than twice per month
- No interference with normal physical activities
- Using a short-acting beta agonist (SABA) for symptoms on no more than 2 days per week
- FEV1 ≥80% predicted or peak flow ≥80% personal best without pre-test use of a bronchodilator
- No more than one exacerbation requiring use of oral systemic steroids or higher level of care (e.g., hospitalization, intubation) over the past 1 year
The criteria related to scores on the cited validated questionnaires have not been included in the assessment criteria in this document due to the likely elevated risk of employment concern bias on the part of the respondents. If scores of any of these questionnaires are available from medical records, it is reasonable to take them into consideration, though they should have been administered within a few weeks of the LEO evaluation and there should not have been any changes in management plan in the interim for them to be valid. LEOs who do not meet all of the criteria for either well-controlled or not-well-controlled asthma should be classified in the next less well-controlled category.
The implication of classifying asthma as not-well-controlled and poorly controlled is 2-fold. First, there are likely actions that can be taken that might improve control. At least one published study has demonstrated ability to gain essentially complete control in all adult subjects with asthma (smokers were excluded as well as some other classes). Secondly, since both categories have “increased risk of exacerbations” as a criterion, there is an implied increased risk of possible impairment during performance of essential law enforcement job functions.
LEOs with the following characteristics on the various criteria should be classified as not-well-controlled:
- Personal report or documented evidence over the 4 weeks prior to evaluation of:
- Symptoms on more than 2 days per week
- Nighttime awakening from bronchospasm 1-3 times/week
- Some limitation in normal physical activities
- Using a short-acting beta agonist (SABA) for symptoms on more than 2 days per week
- FEV1 60-80% predicted or peak flow 60-80% personal best without pre-test use of a bronchodilator
- Two or more (≥2) exacerbations requiring use of oral systemic steroids or higher level of care (e.g., hospitalization, intubation) over the past year
Using the criteria presented in EPR-3, if a LEO does not meet all of the above criteria for not-well-controlled, he/she should be classified as having poorly controlled asthma.
As noted above, EPR-3 considers that, for purposes of treatment decisions, persons with ≥2 exacerbations requiring oral systemic corticosteroids in the prior year may be considered as having not-well-controlled asthma even if the other criteria in this list are not met. The rationale was that the increased number of exacerbations of the specified degree was associated with a significant, though unspecified, increase in risk of exacerbations requiring professional health care intervention up to and including ICU care and intubation. Thus, even if someone had been only moderately impaired by the asthma over the prior 4 weeks and the FEV was not markedly decreased, the risk of exacerbation was felt to be enough to justify re-assessment and possible adjustment of baseline treatment.
Poorly Controlled Asthma
LEOs with the following characteristics on the various criteria should be classified as poorly controlled:
- Personal report or documented evidence over the 4 weeks prior to evaluation of
- Symptoms throughout the day every day;
- Night-time awakening from bronchospasm ≥4 times/week;
- Significant/extreme limitation in normal physical activities;
- Using a short-acting beta agonist (SABA) for symptoms several times per day;
- FEV1 ≤60% predicted or peak flow ≤60% personal best without pre-test use of a bronchodilator;
- Two or more (≥2) exacerbations requiring use of oral systemic steroids or higher level of care (e.g., hospitalization, intubation) over the past year.
As noted above, persons who meet any of the symptom or spirometry criteria of poorly controlled should be considered as having poorly controlled asthma. It is the consensus of the Task Group that LEOs with poorly controlled asthma would have a high likelihood to have difficulty performing various physically strenuous law enforcement job functions.
Many persons with asthma have some degree of increased reactivity to airborne particles such as pollens and dust, however a subset have IgE-mediated allergic reactions that activate bronchospasm. The general medical management recommendation for such persons involves avoidance and desensitization immunotherapy. Persons who do not respond to avoidance or desensitization in addition to use of either inhaled or oral corticosteroids plus long-acting bronchodilators may respond to immunomodulatory treatments.
LEOs are exposed to a variety of potential allergens without advance knowledge. Thus, avoidance is not a particularly viable operational tactic to mitigate the risk of bronchospasm. Additionally, use of rescue inhalers upon realization of exposure or at onset of symptoms may not be operationally practical.
LEOs with allergic asthma may well have baseline asthmatic reactions as well as baseline altered pulmonary functions that may interfere with physical activities. Thus, as above, it is recommended that they also undergo job task simulation testing.
Reassessment Following Failure of Adequate Performance of Job Simulation Tasks and/or review of Care by Treating Physicians
LEOs with asthma who are unable to meet the agency criteria on physical activity challenge testing should be referred to their treating physicians for evaluation and optimization of control of their asthma.
Less than optimal control of asthma might be from inadequate pharmacological control of bronchial inflammation or from the presence of comorbidities such as obesity or exposure to irritants (e.g., cigarette smoke).21 In one large trial, approximately 70% of adults with asthma achieved high levels of control with optimization of a pharmacologic regimen. It has been postulated that the failure to achieve control in the remaining 30% may be associated with the limitations of the current model that all asthma is based on airway inflammation.
With the increasing understanding of more discrete phenotypes of asthma, it has become evident that there are some patients who, despite complete compliance with optimal currently advocated medication regimens, continue to have persistent poor symptom control. These persons will likely need subspecialist consultations with specialized testing and treatment.
Response to increases in inhaled corticosteroid doses may span several months. The implication of this is that it may take weeks to months for persons with not-well and poorly controlled asthma to reach optimal control.
Once the LEO’s physician has approved them to be evaluated using job simulation tasks, the patient and records should be reviewed by the police physician for familiarization with the treatment plan. It is not anticipated that the police physician would challenge the decision to allow the LEO to take the physical abilities challenge test, although, should the police physician have significant concerns, it is incumbent upon the police physician to challenge the treating physician’s opinion.