Obstructive Sleep Apnea

Do I need a sleep study?

Alicia Chaves, MD

Clinical Case

• You are at your continuity clinic and are seeing your eighth patient. You are about to finish the visit, but Mom has one more issue to discuss:– Your patient snores, seems very sleepy during

the day, and Mom has noticed that sometimes he stops breathing in his sleep.

• What is your next step?– Sleep study vs. ENT referral?

Clinical Question

• In a patient with clinical signs and symptoms of OSA, does T&A improve symptoms, despite sleep study results?

– In other words, do you really need that sleep study?

Obstructive Sleep Apnea

• Sleep disorder characterized by cessation of breathing caused by upper airway obstruction

• May affect 1-3% of children• Gold standard of diagnosis is

polysomnography.• In otherwise healthy children, T&A can

eliminate obstruction in 85-95%.

Clinical effects of OSA

• Disordered sleep patterns

• Daytime sleepiness

• Behavioral problems

• Depression

• Poor school performance

• Pulmonary hypertension

• Growth failure

Polysomnography

• Measures EEG, EMG, pulse oximetry, apneic/hypopneic events

• Expensive, requires overnight stay

• Delayed diagnosis and treatment

Literature Search• PubMed

– Obstructive sleep apnea and diagnosis– Limits: full text, English, all child, RCT– Six results:

• 2: using CPAP in OSA• 1: abx use for tonsillar hypertrophy in OSA• 1: atrial overdrive pacing vs. CPAP• 1: nonsurgical methods of treating upper airway

obstruction

• AND….

The Article• Clinical Assessment of Pediatric Obstructive

Sleep Apnea– Goldstein, et al. Pediatrics. 2004 Jul;114(1):33-43.

– OBJECTIVE: To determine whether children with a clinical assessment suggestive of obstructive sleep apnea (OSA) but with negative polysomnography (PSG) have improvement in their clinical assessment score after tonsillectomy and adenoidectomy (T&A) as compared with similar children who do not undergo surgery.

Initial Analysis

• Prospective, RCT

• Patients: children with clinical diagnosis of OSA

• Intervention: T&A

• Outcome: change in clinical score of OSA

Patient Population

• 78 children, ages 2-14 yrs, with “clinical diagnosis” of OSA

• Inclusion criteria: score >40 on clinical assessment

• Exclusion criteria: craniofacial syndromes, neuromuscular disorders, cranial nerve palsies

Methods

• Clinical assessment score– Scores patients for signs and symptoms of OSA– Includes questions for parents, physical exam

findings, sleep tape, lateral neck film, echo– Score of >40 is “positive”

Clinical Assessment Score

• Goldstein NA, et al. Otolaryngol Head Neck Surg. 1994 Nov;111(5):611-7.

• Used clinical assessment score prospectively to “predict which pts would have + PSG

• Sensitivity: 92%, specificity: 29%• PPV: 50%

Are the results valid?• Was treatment randomized?

– Yes, but only the PSG- group

• Was randomization concealed?– Yes

• Were patients and clinicians blinded to treatment?– Patients-no, some clinicians-yes

• Intention to treat analysis?– No

• Was follow-up sufficiently long and complete?– Yes and no

Are the results valid?

• Were groups similar at the start?

– NO

Results

• PPV of clinical assessment score for +PSG was 48%

• Change score for PSG- T&A group was significantly higher than PSG- nonsurgery group.

• The number of pts with a score of <40 following intervention was significantly higher in PSG- T&A group vs nonsurgery group

Score:

>20

>40

RRR

(Relative Risk Reduction)

ARR

(Absolute Risk Reduction)

NNT

(Number Needed to Treat)

CER(Control Event Rate)

EER(Experimental Event Rate)

CER-EER

CER CER-EER 1/ARR

0.78

 0.44

0.18

0

0.77

1

0.6

0.44

2

3

Confidence Intervals

Score >20 Score >40

95% CI for ARR 0.25-0.95 0.12-0.76

95% CI for NNT 2-4 2-9

Are the results useful?

• Can the results be applied to my patient?– Yes…

• Were clinically important outcomes considered?– Yes, but…

Are the results useful?

• Are the likely treatment benefits worth the harms and costs?– Risks of T&A– Spontaneous resolution of OSA sxs– Intensive clinical assessment score