Simulation study highlights potential driving risk posed by patients with obstructive sleep apnea

The potential driving risk posed by patients with obstructive sleep apnoea syndrome (OSAS) is highlighted in a simulation study presented today (7 September, 2016) at this year’s European Respiratory Society (ERS) International Congress in London. The study is by Dr Akshay Dwarakanath and Dr Mark Elliott, St. James’ University Hospital, Leeds, UK and colleagues.

Some OSAS patients are at higher risk of being involved in traffic accidents. There is significant variation in the advice given by doctors on this issue. However, in this study, standard deviation of lane position (SDLP) in a driving simulator was used to try to identify potential risk and create a model for use in future cases.

Various data were collected from patients, including their ‘Epworth Sleepiness Score’(ESS) – a validated sleepiness score to assess subjective sleepiness, and also their oxygen desaturation index (ODI) – a measure of the severity of their OSAS. A total of 129 untreated OSAS patients (Mean age 53 years, ESS 14, ODI 41,Body mass index 36, years with driving licence 31) and 79 controls (mean Age 56 years, ESS 4, BMI 28, licence years 34) completed a driving questionnaire prior to simulator run. Controls performed the simulator run once while OSAS patients performed the simulator run on two occasions. Simulator outcome was based on preset criteria, with three potential results – pass, intermediate, and fail.

OSAS patients as compared to controls reported more episodes of nodding, admitted to a high chance of sleepiness while driving, and were less likely to pass (31% versus 53%) and more likely to fail (20% v/s 0%) than controls. In the controls, 53% passed, 47% were intermediate and nobody failed. In the OSAS patients, 31% passed, 49% were intermediate and 20% failed. Lane deviation was significantly worse in those who failed the test.

Posted in light of OSAS being more frequent in people with schizophrenia.