Free Shipping on All Orders $75 Or More! Ends January 31st.

Your Trusted Brand for Over 35 Years

Health Protocols

Sleep Apnea

Diagnosis

Screening

Given the high prevalence of sleep apnea and its association with serious health conditions, simple clinical screening for obstructive sleep apnea in high-risk groups is important. Symptoms such as snoring, excessive daytime sleepiness, and reports of sleep disordered breathing accompanied by obesity, cardiovascular disease, type 2 diabetes, or metabolic syndrome are likely to indicate candidates for further screening or intervention (Seetho 2013). Before diagnosing sleep apnea, physicians must rule out a number of other conditions that can cause similar symptoms (Gutierrez 2013).

Various screening questionnaires have been developed in order to predict the existence and severity of obstructive sleep apnea, as well as the likelihood of clinical complications of obstructive sleep apnea in pre-surgical and hospital settings. One of the most well validated is STOP-BANG, which stands for “Snoring, Tiredness during daytime, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender” (Braido 2014). A STOP-BANG score of three or more (out of eight) is a sensitive indicator of obstructive sleep apnea, while a score of six out of eight is a highly specific indicator of severe obstructive sleep apnea (Chung 2013; Proczko 2014; Chung 2012; Silva 2011).

Testing

The definitive test for sleep apnea is an overnight polysomnography, often called a sleep study. This test is done in a laboratory and monitors the occurrence of apneic (paused) and hypopneic (shallow and/or slow) breathing episodes by measuring respiratory effort, airflow, and blood oxygen saturation. Polysomnography also includes neurological testing to monitor limb movements, body position, and the sleep-wake state (Jordan 2014).

The accepted criterion for a diagnosis of sleep apnea is five or more episodes of apnea or hypopnea per hour lasting for 10 or more seconds each. Diagnosis of mild, moderate, or severe sleep apnea is based on clinical presentation and sleep study results (De Backer 2013).

American Academy of Sleep Medicine Obstructive Sleep Apnea Classifications (Gutierrez 2013)


Classification

AHI*

Clinical presentation and associated risks

Mild**

5–15 episodes per hour

  • Mild sleepiness or insomnia
  • Mildly low oxygen levels
  • Benign cardiac arrhythmias

Moderate

15–30 episodes per hour

  • Moderate daytime sleepiness, fatigue that interferes with normal daily activities
  • Moderately low oxygen levels and/or mild cardiac arrhythmias
  • At risk for injuries/accidents
  • At risk for high blood pressure, heart attack, stroke and right-sided heart failure

Severe

>30 episodes per hour and/or hypoxia <90% for >20% of total sleep time

  • Daytime sleepiness interferes with normal daily activities
  • Severely low oxygen levels
  • Moderate-to-severe cardiac arrhythmias
  • At risk for injuries/accidents
  • At significant risk for high blood pressure, heart attack, stroke, and right-sided heart failure

*AHI, apnea-hypopnea index
** Patients with mild obstructive sleep apnea (ie, 5–15 episodes per hour) may be asymptomatic.

Because polysomnography is cumbersome, expensive, and inconvenient, portable monitoring devices are sometimes used in the home to aid in diagnosis. Two examples of portable devices that have been found comparable to polysomnography, and which, in the future, may be useful as stand-alone diagnostic tools, are a portable pulse oximeter, which can attach to a finger and non-invasively measure oxygen saturation as it rises and falls during sleep (Romem 2014), and a peripheral arterial tonometer, which measures changing vascular tone (Yalamanchali 2013).