Obstructive sleep apnoea syndrome among taxi drivers : consequences and barriers to accessing health services : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Public Health at Massey University, Sleep/Wake Research Centre, Wellington Campus, New Zealand

Abstract

Untreated Obstructive Sleep Apnoea Syndrome (OSAS) increases the risk of motor vehicle accidents and morbidity. Its prevalence among taxi drivers is unknown. The goals of this thesis were to: (1) estimate the prevalence of OSAS symptoms and risk factors among taxi drivers; and (2) identify the barriers to accessing health care services for the diagnosis and treatment of OSAS. Between June and July 2004 questionnaires were mailed to 651 taxi drivers from two Wellington taxi companies (response rate 41.3%, n=241). Excessive daytime sleepiness (ESS>10) was reported by 18% of drivers. The estimated proportion with a pre-test risk of OSA (RDI≥ 15/hour) was 15%, according to a questionnaire-based screening tool. Pacific drivers were more likely to report OSAS symptoms than people of "other" (non-Māori) ethnicities. Logistic regression analyses identified the following independent risk factors for OSAS symptoms: increasing neck size, age groups: 46-53 years and 61-76 years, and self-reported snoring 'always'. Three focus groups were conducted in November 2004. Thematic analyses identified the following barriers to accessing health care: (1) sleepiness was not a perceived health problem; (2) personal demands; (3) industry demands; and (4) driver avoidance and dissatisfaction with general practitioner's services. Detailed examination of these themes indicated that drivers were deterred from seeking care by limited knowledge and awareness of OSAS, confusion about responsibility for health and safety, medical costs, and the risk of finding out about other health conditions. General practitioners reportedly failed to screen for OSAS symptoms and demonstrated little knowledge about sleep health. These barriers are a major cause for concern, and they are used to support the belief that earning a living is more important than personal health and safety. The key finding is that improving drivers' knowledge is unlikely to change their behaviour, without concurrent measures to address systemic issues in the taxi industry and in the health care system.