Please interpret the ApneaLink Air sleep study results showing 6 apneas, 54 hypopneas, apnea‑hypopnea index (AHI) 7.4 events per hour, supine AHI 12.8, non‑supine AHI approximately 3–4, oxygen desaturation index (ODI) 6.3, baseline oxygen saturation (SpO₂) 98% and lowest SpO₂ 83%.

ApneaLink Air Sleep Study Interpretation

This study demonstrates mild obstructive sleep apnea (OSA) with an overall AHI of 7.4 events/hour, but reveals clinically significant positional OSA with supine AHI of 12.8 events/hour, indicating moderate OSA severity when supine. 1, 2

Severity Classification

Overall OSA Severity: Mild

• The overall AHI of 7.4 events/hour falls into the mild OSA category (AHI 5-15 events/hour) according to American Academy of Sleep Medicine criteria 3, 1, 2
• The study captured 6 apneas and 54 hypopneas over 8.07 hours of flow evaluation, yielding 60 total respiratory events 1
• The apnea index (AI) of 0.7 is minimal, with hypopnea index (HI) of 6.6 accounting for the majority of respiratory events 1

Positional OSA: Clinically Significant

• Supine AHI of 12.8 events/hour represents moderate OSA severity when supine (51.8% of recording time) 1, 2
• Non-supine AHI of 3.3 events/hour is within normal range 1
• The supine-to-non-supine ratio is approximately 3.9:1, far exceeding the 2.0 threshold for positional OSA 1, 4
• This 2-3 fold increase in supine AHI compared to non-supine positions is characteristic of supine-predominant OSA 1

Oxygen Saturation Analysis

Oxygen Desaturation Pattern: Mild

• ODI of 6.3 events/hour correlates well with the AHI of 7.4, confirming mild OSA severity 4, 5
• The correlation between AHI and ODI is typically 0.97, and this patient's values show excellent concordance 4
• Baseline SpO₂ of 98% and average SpO₂ of 97% indicate good overall oxygenation 6
• Lowest SpO₂ of 83% represents moderate desaturation but occurred transiently with no time spent below 88% 6
• Zero time with SpO₂ ≤90%, ≤88%, ≤85%, or ≤80% indicates absence of sustained hypoxemia 6, 5

Clinical Implications

Positional Therapy Candidacy

• This patient is an excellent candidate for positional therapy given the marked difference between supine (AHI 12.8) and non-supine (AHI 3.3) positions 1
• Devices or techniques that discourage supine sleep are specifically recommended when ≥70% of sleep time is supine and positional OSA is demonstrated 1
• The patient spent 51.8% of time supine, and avoiding supine sleep could potentially reduce AHI to near-normal levels 1

Diagnostic Adequacy

• This home sleep apnea test (HSAT) is technically adequate with 8+ hours of recording time and valid oximetry data throughout 3
• The study was scored using AASM 2012 guidelines with manual scoring, meeting quality standards 3
• No evidence of central sleep apnea (central AI 0.1) or Cheyne-Stokes respiration 3

Common Pitfalls and Caveats

Underestimation Risk

• The overall AHI of 7.4 may underestimate true OSA severity because the patient spent only 51.8% of time supine 1
• If this patient typically sleeps supine at home, the true nightly AHI may be closer to 12.8 events/hour (moderate OSA) 1
• REM-predominant OSA often co-exists with positional dependence and can lead to further underestimation of disease severity 1

Night-to-Night Variability

• Approximately 15% of patients show significant AHI variability between nights, and 6% with severe OSA may be missed on a single night study 7
• If clinical suspicion remains high despite this mild result, consider repeat testing per American Academy of Sleep Medicine guidelines 3

Need for Confirmatory Testing

• If this HSAT result is negative, inconclusive, or technically inadequate, polysomnography should be performed 3
• Patients with significant cardiorespiratory disease, neuromuscular conditions, chronic opioid use, stroke history, or severe insomnia should undergo polysomnography rather than HSAT 3

Treatment Recommendations

Primary Approach: Positional Therapy

• Given the 3.9-fold increase in AHI when supine, initial management should focus on supine avoidance strategies 1
• If positional therapy fails to control symptoms or the patient cannot maintain non-supine sleep, consider CPAP therapy 3

Alternative Considerations

• The moderate supine AHI of 12.8 may warrant CPAP therapy if symptoms are significant or cardiovascular risk factors are present 3
• Clinical correlation with symptoms (daytime sleepiness, witnessed apneas, unrefreshing sleep) is essential for treatment decisions 3