Note from the Scottish Intercollegiate Guidelines Network (SIGN) and National Guideline Clearinghouse (NGC): In addition to these evidence-based recommendations, the guideline development group also identifies points of best clinical practice in the original guideline document.
The strength of recommendation grading (A-D) and level of evidence (I++-4) are defined at the end of the "Major Recommendations" field.
Diagnosis
C - All patients who have suspected sleep apnoea and their partners should complete an Epworth questionnaire to subjectively assess the degree of pretreatment sleepiness.
Diagnostic Tools
B - Limited sleep studies to assess respiratory events are an adequate first-line method of diagnostic assessment for obstructive sleep apnoea/hypopnoea syndrome (OSAHS).
Treatment
Behavioural Interventions
C - Weight loss should be encouraged in all patients with obesity contributing to their OSAHS. Attempts at weight loss should not delay the initiation of further treatment. Weight loss should also be encouraged as an adjunct to continuous positive airway pressure (CPAP) or intra-oral devices as it may allow discontinuation of therapy.
Non-Surgical Interventions
CPAP
A - CPAP is the first choice therapy for patients with moderate or severe OSAHS that is sufficiently symptomatic to require intervention.
C - Persistent low CPAP use (less than two hours per night) over six months, following efforts to improve patient comfort, should lead to a review of treatment.
B - Bi-level ventilation should not be used routinely in OSAHS but should be reserved for patients with ventilatory failure.
Intra-Oral Devices
A - Intra-oral devices are an appropriate therapy for snorers and for patients with mild OSAHS with normal daytime alertness.
B - Intra-oral devices are an appropriate alternative therapy for patients who are unable to tolerate CPAP.
D - The use of intra-oral devices should be monitored following initiation of therapy to allow device adjustment and assessment of OSAHS control and symptoms.
Pharmacological Therapy
A - Pharmacological therapy should not be used as first line therapy for OSAHS.
Surgical Intervention
B - Use of uvulopalatopharyngoplasty (UPPP) or laser-assisted uvulopalatopharyngoplasty (LAUP) for the treatment of OSAHS is not recommended.
D - Patients being offered palatal surgery should be informed of the risk of difficulty with CPAP use if they later develop OSAHS.
Effects of Treatment on driving and quality of life
A - CPAP should be considered for the improvement of driving ability in patients with severe OSAHS as it reduces daytime sleepiness.
Definitions:
Grades of Recommendation
A: At least one meta-analysis, systematic review of randomised controlled trials (RCTs), or RCT rated as 1++ and directly applicable to the target population; or
A body of evidence consisting principally of studies rated as 1+, directly applicable to the target population, and demonstrating overall consistency of results
B: A body of evidence including studies rated as 2++, directly applicable to the target population, and demonstrating overall consistency of results; or
Extrapolated evidence from studies rated as 1++ or 1+
C: A body of evidence including studies rated as 2+, directly applicable to the target population and demonstrating overall consistency of results; or
Extrapolated evidence from studies rated as 2++
D: Evidence level 3 or 4; or
Extrapolated evidence from studies rated as 2+
Levels of Evidence
1++: High quality meta-analyses, systematic reviews of randomised controlled trials (RCTs), or RCTs with a very low risk of bias
1+: Well-conducted meta-analyses, systematic reviews of RCTs, or RCTs with a low risk of bias
1-: Meta-analyses, systematic reviews of RCTs, or RCTs with a high risk of bias
2++: High quality systematic reviews of case control or cohort studies; high quality case control or cohort studies with a very low risk of confounding or bias and a high probability that the relationship is causal
2+: Well conducted case control or cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal
2-: Case control or cohort studies with a high risk of confounding or bias and a significant risk that the relationship is not causal
3: Non-analytic studies, e.g. case reports, case series
4: Expert opinion