Sleep Disorders

Obstructive Sleep Apnea

Clinical Characteristics
Obstructive sleep apnea (OSA) is characterized by repetitive episodes of upper airway obstruction and apnea that occur during sleep, typically associated with a reduction in blood oxygen saturation.3(p52) Apneic episodes are usually terminated by brief arousals from sleep and heroic snoring. Frequently, a bed partner will recognize the apnea and wake the person to restart breathing.

Untreated or inadequately treated OSA will impair wakefulness, vigilance, situational awareness, and executive functioning. Examples of LEO job functions that may be affected are: operating a vehicle during routine patrol, investigating, cognitive decision-making, and deciding when to use deadly force. The LEO may also find it difficult to stay awake while performing sedentary, mundane tasks.

Untreated or inadequately treated OSA also places the LEO at increased risk of hypertension, sudden cardiac death, stroke, cardiac arrhythmias, myocardial ischemia, the metabolic syndrome, depression, car crash, and/or marital discord.6

The most common risk/leo/shoulder-disorders/references-shoulder factors for OSA include obesity (although sleep apnea may occur in persons who are not overweight), neck circumference, smoking, male gender, decreased caliber of the upper airway (e.g., due to enlarged tonsils), Asian or Hispanic ethnicity, and increasing age. Emerging evidence indicates that there is a genetic predisposition as well.7

Screening and Diagnostic Tests
When off-duty behaviors or work performance raise suspicion that the LEO may have OSA, he or she should be referred to the police physician for evaluation (see Appendix C). As part of that evaluation, a screening test can determine whether further diagnostic studies, such as the polysomnogram (sleep study) are needed to confirm or rule out a diagnosis of OSA or other condition.

Body mass index (BMI) is a readily available screening tool for stratifying risk of having sleep apnea. Evaluation for sleep apnea should be considered for LEOs with a BMI >32 (ACOEM Task Group consensus).8,9 A 2013 report that examined 104 drivers suggested improved sensitivity (but worsening specificity) when using a BMI >30.10

Screening tests that solely consist of self-reported behaviors and symptoms (e.g., the Epworth Sleepiness Scale11) should be avoided. A negative Epworth is not useful because the individual may be unaware of – or is in purposeful or unconscious denial of – the behaviors and symptoms associated with suspected OSA.12

Treatment of OSA
Continuous Positive Airway Pressure (CPAP)
The cornerstone of OSA treatment is positive airway pressure (PAP). This is generally provided as continuous positive airway pressure (CPAP),b although bilevel positive airway pressure is sometimes used. However, while more expensive, there is no evidence that bilevel pressure is more effective. CPAP has been shown to reduce the risk of crash in commercial motor vehicle drivers, and is also associated with lowered blood pressure, improved cognition, reduced sleepiness, and reduction in death from cardiovascular disease. As with any medical treatment, adherence to CPAP treatment affects its efficacy.13

The goal for LEOs using CPAP is an average use of 4 hours per sleep sessions, on at least 70% of sessions (consensus based on sleep literature).14 The LEO should be made aware that missing a session of sleep with CPAP is the equivalent of never using it at all15; “…discontinuation of CPAP either one night, or even half of the night resulted in the recurrence of obstructive respiratory events and the clinical sequelae of untreated OSA including hypersomnia.”16

No alternative and adjunct therapy for treatment of OSA other than CPAP is consistently associated with reduced risk of crash.

Oral Appliances
Oral appliances that are custom made by dentists have been demonstrated in randomized controlled trials to improve sleepiness, blood pressure, and oxygenation compared with placebo. For this reason, oral appliances are the most commonly used form of treatment for individuals who cannot (or will not) use PAP or who have mild disease. These appliances are less effective than CPAP, but more effective than placebo (see Appendix D – Periodic Assessment of LEOs Using Oral Appliances).

Surgery
Surgery to increase the size of the upper airway opening (e.g., tonsillectomy or uvulopalatopharyngoplasty) is generally ineffective in adults.17 LEOs who undergo this form of treatment should have follow-up sleep studies to assess the results before being cleared to return to duty. Weight loss can enhance the effects of other therapies, and in some cases, may eliminate OSA.

Expiratory Resistance Valves
Expiratory resistance valves, also known as expiratory nasal positive airway pressure, have been shown in carefully selected patients to improve OSA. The effect of this device on driving and blood pressure is unknown.

Medications
Both modafinil (Provigil) and armodafinil (Nuvigil) have been found to be effective adjuvant treatments of excessive sleepiness, even in those who are compliant with CPAP. These agents are approved by the Food and Drug Administration (FDA) for the treatment of residual sleepiness in patients with OSA or shift workers, however they are expensive.

There is currently insufficient evidence to recommend any systemic pharmacological treatment for OSA. Modafinil, armodafinil, and other classes of medications (e.g., drugs proposed to act on airway tone during sleep, drugs proposed to act on ventilator drive, vasoactive drugs, topical drugs for the upper airway, cholinesterase inhibitors, non-benzodiazepine sedatives18) should not be used as first-line and/or monotherapy treatment for OSA, and should never be used instead of CPAP.

Smoking cessation and avoidance of sedating medications (e.g., over-the-counter sleep aids, muscle relaxants, opioids, benzodiazepines), and alcohol should be standard recommendations.

LEO-Specific Clinical Studies and Reports
A systematic review of the medical literature identified a few reports that address LEOs and sleep disorders; however, most of these reports focused on sleep deprivation and shift work. One large survey of LEOs found that 34% of participants screened positive for sleep apnea.2,19

Fitness-for-Duty Criteria
For the LEO identified to be at risk for sleep apnea, or who has untreated or sub-optimally treated OSA, duty status should be determined on a case-by-case basis by supervisors with consultation with the police physician. The following criteria may be considered20:

• Observed unexplained excessive daytime sleepiness (sleeping in examination or waiting room) or confessed excessive sleepiness.
• Motor vehicle crash (run off road, at fault, rear-end collision) likely related to sleep disturbance unless evaluated for sleep disorder in the interim.
• Observed performance impairment of LEO essential job tasks suspected to be due to somnolence and associated decreased vigilance, executive functioning, and judgement (see Appendix C).
• Previously diagnosed OSA: 1) noncompliant (continuous positive airway pressure treatment not tolerated); 2) no recent follow-up (within recommended time frame); and 3) any surgical approach with no objective follow-up.

LEOs who have been diagnosed with OSA who are using CPAP should be monitored for consistent use and therapeutic efficacy. The police physician should review data accessed from the CPAP machine on at least an annual basis, and as part of an intervention triggered by early warning signs. A worksheet for the joint use by the police physician and treating physician in the fitness for duty evaluation for OSA can be found in Appendix D – OSA Worksheet Data Elements.