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First night effect for polysomnographic data in children and adolescents with suspected sleep disordered breathing
S L Verhulst1, N Schrauwen, W A De Backer
1Department of Pediatrics, University Hospital of Antwerp, Belgium. stijn.verhulst@ua.ac.be
Insights
A first night effect (FNE) is present in children and adolescents undergoing polysomnography (PSG). A single PSG night is generally sufficient for diagnosing obstructive sleep apnoea syndrome (OSAS), though a second night may be needed in select cases.
Area of Science:
- Pediatric Sleep Medicine
- Respiratory Physiology
- Clinical Diagnostics
Background:
- The first night effect (FNE) describes altered sleep patterns during polysomnography (PSG) on the initial night of testing.
- Understanding FNE in pediatric populations is crucial for accurate obstructive sleep apnoea syndrome (OSAS) diagnosis.
- Previous research on FNE has primarily focused on adult populations.
Purpose of the Study:
- To evaluate the presence and impact of FNE in children and adolescents.
- To determine if a single-night PSG is adequate for diagnosing OSAS in pediatric patients.
- To assess the diagnostic accuracy of a single-night PSG compared to a two-night study.
Main Methods:
- A prospective case study involving 70 pediatric patients (aged 2-17 years) referred for suspected OSAS.
- Patients were categorized into three age groups: 2-6 years, 7-12 years, and 13-17 years.
- Diagnostic criteria for OSAS included specific indices of obstructive apnoea and oxygen saturation levels during PSG.
Main Results:
- Rapid eye movement sleep (REMS) increased on the second night, particularly in older children, at the expense of stage 2 sleep.
- A single PSG correctly identified OSAS in 86% (2-6 yrs), 91% (7-12 yrs), and 100% (13-17 yrs) of patients.
- A 9% false-negative rate for OSAS was observed with a single PSG, primarily in mild cases, with seven patients showing OSAS on night 1 but not night 2.
Conclusions:
- A first night effect is evident in children and adolescents undergoing polysomnography.
- While a single-night PSG is generally sufficient for diagnosing pediatric OSAS, a second night may be beneficial in specific clinical scenarios.
- In patients with suggestive symptoms and a negative first-night PSG, a follow-up second-night study is advisable.
Aims:
To assess the presence of a first night effect (FNE) in children and adolescents and to examine if a single night polysomnography (PSG) is sufficient for diagnosing obstructive sleep apnoea syndrome (OSAS).
Methods:
Prospective case study of 70 patients (group 1: 2-6 years, n = 22; group 2: 7-12 years, n = 32; group 3: 13-17 years, n = 16) referred for OSAS. Diagnostic criteria for OSAS: one or more of the following: (1) obstructive apnoea index (OAI) > or =1; (2) obstructive apnoea hypopnoea index (oAHI) > or =2; (3) SaO2 < or =89% in association with obstruction.
Results:
In all age groups, but mainly in the oldest children, REMS increased during the second night, mainly at the expense of stage 2 sleep. The first night PSG correctly identified OSAS in 86%, 91%, and 100% of the children for groups 1, 2, and 3 respectively. This represents 9% false negatives for OSAS when only the first night PSG was used. All cases missed had mild OSAS, except for one with oAHI >5 on night 2. There were also seven patients with OSAS on night 1 but with a normal PSG on night 2: all had oAHI <5.
Conclusion:
There is a FNE in children and adolescents. A single night PSG is sufficient for diagnosing OSAS, but in cases with a suggestive history and examination and with a negative first night, a second night study might be advisable.
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