This NICE guideline (NG202) covers the diagnosis and management of obstructive sleep apnoea/hypopnoea syndrome (OSAHS) and obesity hypoventilation syndrome (OHS) in people aged 16 and over. These conditions are frequently under-recognised despite their impact on daytime functioning, cardiovascular risk, and long-term morbidity. The guidance also includes considerations for people with COPD–OSAHS overlap syndrome, a subgroup at even higher risk of complications.

The guideline aims to improve clinical recognition, guide appropriate investigations, and recommend effective management strategies, especially relevant to primary care clinicians who are often the first point of contact. By enhancing early identification and timely referral, primary care can play a key role in reducing the burden of these conditions and improving patient quality of life.

Initial Assessment for OSAHS (NICE NG202)

Definition

OSAHS is a condition where the upper airway narrows or closes during sleep, causing apnoeas or hypopnoeas. These disruptions lead to sleep fragmentation and symptoms like daytime sleepiness, tiredness, or fatigue.

📨 Referral for Suspected OSAHS: When and How to Prioritise

Timely referral to a sleep service is key for people with suspected Obstructive Sleep Apnoea/Hypopnoea Syndrome (OSAHS)—especially where there are safety-critical jobs or clinical risks. This section outlines what to include in a referral and who should be prioritised for rapid assessment.

Patient Profile	Recommended Action
Person with ≥2 OSAHS features (including if BMI ≥30 kg/m² or COPD)	• Take a sleep history and assess for OSAHS • Use the Epworth Sleepiness Scale (not as sole criterion) • Consider using the STOP-Bang Questionnaire
Person with BMI ≥30 kg/m² and features of OSAHS or nocturnal hypoventilation	• Take a sleep history and assess for Obesity Hypoventilation Syndrome (OHS) • Use the Epworth Sleepiness Scale (not alone)
Person with COPD and features of OSAHS or nocturnal hypoventilation	• Take a sleep history and assess for OSAHS-COPD overlap syndrome • Use the Epworth Sleepiness Scale (not alone) • Consider using the STOP-Bang Questionnaire • Offer spirometry to assess COPD severity

🧪 Diagnostic Tests for OSAHS (NICE NG202)

Introduction

Accurate diagnosis of Obstructive Sleep Apnoea/Hypopnoea Syndrome (OSAHS) is crucial for effective treatment planning. NICE recommends a tiered approach to diagnostic testing, starting with home-based options and escalating based on availability and symptom persistence. The results of these tests are used to both confirm the diagnosis and determine the severity of OSAHS—categorized as mild, moderate, or severe.

💊 Overview: Treatment Options for OSAHS (NICE NG202)

Introduction for Primary Care

Treatment for Obstructive Sleep Apnoea/Hypopnoea Syndrome (OSAHS) is primarily guided by the severity of symptoms and impact on daytime function, with many interventions provided in secondary care. However, primary care plays a vital role in:

• Initial identification and lifestyle counselling

• Determining who might benefit from CPAP or oral devices

• Supporting ongoing management of rhinitis or sleep-impacting comorbidities

• Understanding referral criteria for surgery or specialist input

🔄 Follow-up & Monitoring for OSAHS – Key Points for Primary Care

• Follow-up is specialist-led and tailored to treatment type (CPAP, splints, positional therapy, or surgery).

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• Initial follow-up:

  • CPAP: within 1 month

  • Mandibular splints & positional modifiers: within 3 months

  • Surgery: within 3 months using respiratory polygraphy

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• Monitoring includes:

  • Symptom review (Epworth Sleepiness Scale, alertness for driving)

  • AHI/ODI indices (severity markers)

  • Adherence and device data (telemonitoring, downloads)

  • Side effects (dryness, sleep disruption)

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• Annual follow-up may be considered once treatment is stable.

• Access to specialist services should be maintained between formal follow-ups (for troubleshooting or equipment issues).

• Support drivers: ensure compliance with DVLA guidance if sleepiness is present.

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🤝 Supporting Treatment Adherence

• Education and support are critical—delivered by trained specialist teams.

• Interventions should be personalised and introduced at treatment start and reinforced during follow-up.

• Consider stopping treatment if OSAHS resolves (e.g., post-weight loss); assess after 2 weeks off therapy.

Managing obstructive sleep apnoea/hypopnoea syndrome (OSAHS) and obesity hypoventilation syndrome (OHS) in individuals over the age of 16 requires a multifaceted and evidence-based approach. This management involves a combination of lifestyle changes, pharmacologic interventions, and advanced therapeutic strategies aimed at reducing the associated morbidity and improving overall health outcomes.

Intervention	Description	Primary Care Role
🏃 Lifestyle & Weight Management ↑	Structured interventions for diet, physical activity, and behaviour change to reduce BMI and improve OSAHS/OHS symptoms.	Provide counselling, refer to dietitians, monitor BMI and reinforce adherence to lifestyle plans.
🫁 CPAP Therapy ↑	Maintains airway patency during sleep; first-line for OSAHS/OHS. Improves sleep quality and reduces cardiovascular risks.	Support patient education, address mask issues, liaise with sleep services, monitor compliance and side effects.
💨 NIPPV ↑	Used for moderate-severe OHS. Enhances ventilation, corrects hypercapnia, prevents respiratory failure during sleep.	Recognise deteriorating patients and refer for specialist respiratory assessment.
💊 Pharmacotherapy ↑	Includes GLP-1RAs for obesity/metabolic control, plus medications for comorbidities like hypertension and diabetes.	Prescribe/manage relevant medications, monitor response, consider GLP-1RA for eligible patients.
🦷 Mandibular Devices ↓	Oral splints reposition the lower jaw; useful when CPAP is not tolerated or declined.	Identify suitable candidates and refer to appropriate dental sleep services.
🔪 Surgical Interventions ↑	Includes bariatric surgery and upper airway procedures for refractory cases.	Support referrals and coordinate post-op monitoring for patients meeting surgical criteria.
🛏 Positional Therapy ↓	Encourages non-supine sleep posture in mild/moderate positional OSAHS.	Educate patients on positioning techniques and assess effectiveness or refer appropriately.
🩺 Comorbidity Screening ↑	Routine checks for CVD, pulmonary hypertension, type 2 diabetes, etc., due to high overlap with OSAHS/OHS.	Integrate into chronic disease reviews; act on abnormal findings; coordinate with specialists as needed.
📚 Education & Support ↑	Essential for treatment adherence (CPAP, devices); includes behavioural support and patient empowerment.	Reinforce messages, follow up on adherence, and provide resources or refer to sleep services when needed.

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