Sleep Apnea Practice Questions

Define sleep apnea and describe its primary characteristics.

Sleep Apnea is a chronic sleep disorder characterized by repetitive episodes of partial or complete upper airway obstruction during sleep, leading to intermittent cessation of breathing (apnea) or reduced airflow (hypopnea).

• Apnea: cessation of airflow ≥10 seconds

• Hypopnea: ≥30% reduction in airflow with ≥3% O2 desaturation

• AHI (Apnea-Hypopnea Index): events/hr — the primary severity metric

What are the two main types of sleep apnea?

1. OSA: Pharyngeal airway collapse despite continued respiratory effort (loss of pharyngeal dilator muscle tone)

2. CSA: No respiratory effort — failure of CNS respiratory drive to send signals to breathing muscles

Compare & contract OSA and CSA based on their pathophysiology, risk factors, and clinical manifestations.

• OSA

  • RF: Obesity (BMI >30), male sex, age >40, enlarged neck circumference (>40 cm M), craniofacial anomalies, alcohol/sedative use, nasal congestion

  • PSG: Paradoxical thoracoabdominal movement present; airflow absent

  • Hallmark: Loud snoring

• CSA

  • RF: HF (Cheyne-Stokes), opioid use, stroke/brainstem lesions, high altitude, idiopathic

  • PSG: Both airflow AND respiratory effort absent simultaneously

  • Hallmark: Insomnia/frequent arousals common

What is mixed/central sleep apnea?

OSA that develops central [brain-related] events during CPAP therapy (i.e., treatment-emergent CSA)

Discuss the role of polysomnography (sleep study) in diagnosing sleep apnea.

What are the key findings typically observed in individuals with sleep apnea during polysomnography?

• Elevated AHI → ≥5 episodes/hr during sleep with sxs; ≥15 episodes/hr during sleep without sxs)

• O2 desaturation <90%

• Sleep fragmentation → frequent arousals after respiratory events

• Reduced slow-wave and REM sleep

• Distinguishes OSA (respiratory effort) vs. CSA (respiratory effort absent)

• Cardia arrhythmias → e.g., nocturnal bradycardia, AF

Explain the potential consequences and complications of untreated sleep apnea on cardiovascular health, cognitive function, and overall quality of life.

CV: HTN (strongest association), AF, HF, CAD, stroke, pulmonary HTN

Cognitive function: Impaired attention, memory, executive function; depression; anxiety; increased risk of dementia

QOL: Excessive daytime sleepiness, impaired work performance, sexual dysfunction, MVA risk

What are the primary treatment modalities for sleep apnea? Discuss the pharmacological and non-pharmacological interventions used in the management of OSA and CSA.

Pharmacological:

• Limited! — there is currently no drug that directly treats airway collapse

  • Modafinil/Armodafinil → wakefulness-promoting agents; not considered primary therapy for OSA

Non-pharmacological:

• CPAP → gold standard; moderate-severe OSA

• Oral appliances → jawbone advancement; mild-moderate OSA or CPAP-intolerant

• Weight loss → 10% weight loss

• Positional therapy → supine sleep increases AHI

• Surgical → not first line; hypoglossal nerve stimulation (Inspire device)

• Lifestyle → limit alcohol intake, smoking cessation

Describe the mechanism of action of continuous positive airway pressure (CPAP) therapy in treating OSA.

Delivers a continuous stream of pressurized air via a nasal/full-face mask, acting as a pneumatic splint that mechanically distends the upper airway, preventing pharyngeal collapse during sleep. It increases functional residual capacity and reduces upper airway resistance.

Describe the efficacy of continuous positive airway pressure (CPAP) therapy in treating OSA.

• Reduces AHI to <5 episodes/hr in most patients

• Improves daytime sleepiness, QOL, and cognitive function

• Reduces BP (~2-3 mmHg)

• Reduces AF recurrence

• Optimal efficacy requires ≥4 hr/night of adherence

Describe the potential side effects of continuous positive airway pressure (CPAP) therapy in treating OSA.

• Mask/pressure discomfort

• Nasal congestion/rhinitis

• Skin irritation

• Dry mouth

Discuss the role of oral appliances in the management of sleep apnea. What is the indication and contraindications for this treatment option?

Discuss the role of surgical interventions in the management of sleep apnea. What is the indication and contraindications for this treatment option?

How does obesity contribute to the development and exacerbation of sleep apnea? Outline the impact of weight loss interventions on sleep apnea severity and outcomes.

Explain the pharmacist’s role in the interdisciplinary management of sleep apnea. What patient education and counseling points are important for individuals diagnosed with sleep apnea?