Scientific Abstract

AIMS.To determine (a) feasibility of testing for obstructive sleep apnoea (OSA) into GP using AcuPebble, (b) if case finding in GP increases detection rate of OSA (c) if GP-based screening is cost-effective.

OBJECTIVES.To determine if the use of AcuPebble increases detection of OSA in high-risk groups; cost effectiveness versus standard practice in people at high-risk; to compare hospital-based referral route with GP based route.

DESIGN. Randomised controlled trial of case-finding of OSA in primary care using a novel MHRA-registered device (AcuPebble SA100) compared to usual care, with internal feasibility phase to assess fidelity of delivery of the device, acceptability to patients and primary care team. After eligibility screening, consent and baseline assessment, participants randomised to either an Intervention or a Control group for 6 months.

RECRUITMENT. Forty GPs from theWest Midlands CRN. They will identify eligible patients meeting the inclusion criteria.

INCLUSION CRITERIA. Age 50-70 years with BMI > 30 Kg/m2and/or diabetes (type 1 or 2) and/or hypertension (office BP >145/90 mmHg or on treatment) as of GP records.

EXCLUSION CRITERIA. Patients with known OSA, those deemed unable to take part by their GP, (e.g. terminally ill), patients with known allergy to acrylate.

INTERVENTION. Participants will receive by post the overnight sleep testing device. No hospital attendance is required, and its use does not require training. The test is comfortable, non-invasive, using a small device attached to the throat, without being attached to leads or wires.

CONTROL. Participants will continue with usual care.

POPULATION.1,426 eligible participants randomised 1:1 to Intervention or Control group. Due to the nature of the intervention, participants and GPs will not be blinded to the allocation. However, the assessment of primary outcomes will be automated.

OUTCOMES.Primary:Intervention OSA detection rate versus control detection rate.Secondary:Time-to-diagnosis and time-to-treatment for new pathway (intervention group) v control group; Cost-effectiveness analysis comparing new vs current pathways; Feasibility and acceptability of new sleep study testing.

ASSESSMENTS. Proportion of participants with a diagnosis of OSA.

SAMPLE SIZE.Detection of new cases of OSA using usual care is <5% per year. Given the observed rates of hypertension, obesity, diabetes mellitus in individuals with OSA, we expect a detection rate of => 10% in the Intervention group. The study is powered (90%) to detect a 5% difference and will require 606 patients in each arm. To allow 15% attrition and lost to follow up, 713 in each arm are need.

FEASIBILITY. An internal feasibility phase will assess fidelity of delivery of the device, acceptability to patients and primary care teams. We will review recruitment, data collection, AcuPebble study, allowing modifications to trial before recruitment starts at month 9.

ANALYSIS. Primary analysis: new cases of OSA diagnosed in Intervention compared to Control group. Secondary analyses: time-to-diagnosis and time-to-treatment for new pathway (intervention group) v control group, cost-effectiveness analysis (new vs current pathway), feasibility and acceptability of sleep study testing.