Diagnosing obstructive sleep apnea in primary care

Project Coordinator

Amanda Siebers (Woolcock Institutue of Medical Research)

Chief Investigators

Prof Ronald Grunstein, Prof Peter A Cistulli, Prof Guy Marks, Prof Nicholas Zwar, Dr Keith K H Wong

Associate Investigators

Dr Lydia Makarie Rofail, Dr Richard Lee, Dr Sarah Dennis

Rationale

OSA is a common and treatable condition, and a source of neurocognitive morbidity and cardiovascular complications. Current polysomnographic resources are insufficient to meet the significant burden of undiagnosed disease. This limitation in availability to diagnosis and therapy, coupled with the high prevalence of OSA, presents a substantial public health risk. Such expensive and resource-limited management models are costly, and may be unnecessarily burdensome. It is timely to develop and systematically evaluate diagnostic alternatives which reduce waiting times as well as manage the growing burden of significant public health interest.

The proposed alternative model will include attention to the GP as the initial contributor to the pathway which will ultimately lead to appropriate therapy and positive outcomes for OSA patients. This system should address both the extant burdens, while offering substantial savings in both direct and indirect costs to the Australian healthcare system. This will also help to equalize access to care for those in rural and remote areas.

GP-controlled simple diagnostic testing may offer advantages of reduced cost and more rapid availability of results. In general these devices have not been extensively studied in the home, or in the primary care setting, there is limited data on any single device, and there is no clear evidence that any one device is superior to the others. The potential loss of diagnostic accuracy from these less complicated devices may be tempered by the addition of clinical information to assess pre-test probability, to allow individualized interpretation of test results, and identifying situations in which the test is likely to be inaccurate.

Aims

The aim of this project is to simplify the method for diagnosing obstructive sleep apnea (OSA) in the primary care setting.

The specific aims of this project are:

Phase 1: to derive a diagnostic algorithm combining information from questionnaire and anthropometric clinical data, craniofacial phenotyping and portable monitoring of breathing during sleep for use in the primary care setting.

Phase 2: to prospectively validate the newly−developed model from phase 1 in the primary care setting.

Design and Method

The project will proceed in two phases: first developing a diagnostic algorithm that would combine information from questionnaire, anthropometric clinical data, craniofacial photography and a portable diagnostic device. Secondly, we will prospectively validate this diagnostic algorithm. The proposed project involves an established team of clinicians and researchers from a number of sleep centres, urban and rural general practice, biostatistics and clinical epidemiology. We have already generated pilot data from 5 primary practices in metropolitan Sydney, confirming the feasibility of our approach and we propose to extend this to rural communities. This validation will provide a strong evidence base for a future randomized controlled trial to test the effectiveness of management strategies based on the application of the diagnostic algorithm in primary care.