Sleep disorders, medical conditions, and road accident risk

Abstract

Sleep disorders and various common acute and chronic medical conditions directly or indirectly affect the quality and quantity of one's sleep or otherwise cause excessive daytime fatigue. This article reviews the potential contribution of several prevalent medical conditions – allergic rhinitis, asthma, chronic obstructive pulmonary disease, rheumatoid arthritis/osteoarthritis – and chronic fatigue syndrome and clinical sleep disorders – insomnia, obstructive sleep apnea, narcolepsy, periodic limb movement of sleep, and restless legs syndrome – to the risk for drowsy-driving road crashes. It also explores the literature on the cost-benefit of preventive interventions, using obstructive sleep apnea as an example. Although numerous investigations have addressed the impact of sleep and medical disorders on quality of life, few have specifically addressed their potential deleterious effect on driving performance and road incidents. Moreover, since past studies have focused on the survivors of driver crashes, they may be biased. Representative population-based prospective multidisciplinary studies are urgently required to clarify the role of the fatigue associated with common ailments and medications on traffic crash risk of both commercial and non-commercial drivers and to comprehensively assess the cost-effectiveness of intervention strategies.

Introduction

The field of occupational medicine generally views fatigue as the cumulative effect of one's work parameters, e.g., shift duration, work hours/week, shift start time, mental/physical workload, job monotony, and commute time, as discussed elsewhere in these proceedings (Williamson et al., 2011). However, we feel this perspective is too restrictive, since many other factors can play a contributing or even prominent role. These include demographic variables, as reviewed elsewhere in these proceedings by Di Milia et al. (2011), various acute and chronic medical conditions (sleep disorders and clinical ailments), and certain prescribed and over-the-counter medications as reviewed here. Health status variables are increasingly gaining attention in occupational medicine in terms of the so-called ‘work ability’ of employees, i.e., one's ability to meet workplace demands (Ilmarinen, 2001, Tuomi et al., 1998). Yet, thus far they have received comparatively little consideration as a source of excessive fatigue and being a risk factor for commercial and non-commercial drowsy-driving incidents. Thus, the focus of this article is to illustrate the potential contribution of several major sleep and medical disorders that are highly prevalent in the driving population on daytime fatigue and drowsy-driving incidents.