Apnea and Accident Rate
Sleep Breathing Disorders (SBD) are common and therefore are a frequent source of health problems which have an important economic impact. Lack of sleep is responsible for many road traffic accidents, work-related accidents and domestic mishaps. SBD patients are often drowsy while driving and traffic accidents are a major problem . The social and economical consequences are far reaching. The latest report on global road safety published by the WHO describes traffic accidents as a priority public health issue. 1.2 million people die every year on the roads worldwide and between 20 and 50 million people suffer non-fatal injuries. The death rate from traffic accidents is on the increase and it currently represents the fourth leading cause of death worldwide and the primary cause of death in men between the ages of 15 and 24. for every fatality there are 7 major and 15 minor injuries.
Along with the cost of human lives there are also exorbitant economic costs generated from hospitalisation, rehabilitation, inability to work, compensation claims, vehicle and road network repair. In the European Union, traffic accidents costs range between €180 billion and €240 billion, a figure equivalent to 2% of the EU GDP. According to official ciphers in Spain, the traffic accident figures in 2005 were approximately €14 billion, costing the average Spaniard €400. Equivalent to €42 million per day.
Due to the high prevalence of sleep apnea and the high percentage of accidents caused by this condition, a large proportion of the traffic accident related costs must be directly linked. Therefore the economic burden cause by untreated sleep apnea is measurable in billions of euros per year. The economic burden caused by untreated sleep apnea is measurable in billions of euros a year. Investment in diagnosis and treatment would save human lives and reduce the related economic costs.
The sleepiness caused by apnea is equivalent to that cause by alcohol consumption or the consumption of drugs and can have a disastrous affect on the ability to drive. Drivers may find it difficult to concentrate, being easily distracted and this is the second leading cause of accidents. The risk of having an accident because of sleep deprivation is between 7 and 13 times higher than the norm. Data collected in Spain shows that there are approximately 40,000 Spanish traffic accidents caused by lack of sleep each year and 35% of drivers admitted to having driven whilst sleepy. 25 – 30% of traffic accidents in which human factors are to blame show that the driver had fallen asleep at the wheel. Insomnia and sleep apnea are the most prevalent sleep disorders both causing excessive daytime sleepiness. Of all sleep disorders, sleep apnea is the most deadly when behind the wheel because drivers are unaware that their rest was continuously interrupted overnight.
These individuals report excessive daytime sleepiness and fatigue but feel it unjustified after a night of sleep that they perceive as normal. The vast majority of apnea patients are undiagnosed and they get up each day feeling that they have slept peacefully. However, symptoms of fatigue and even exhaustion, exactly the same as those experience by patients who have not slept, cause real confusion because the patient cannot justify their state of constant drowsiness. They may experience neuropsychological symptoms, perform poorly at work, show a decreased psychomotor ability, memory impairment and even be depressed. The fact that the sufferers are unaware of their condition is an aggravating factor when compared to other sleep disorders such as insomnia or narcolepsy in which sufferers are fully aware of their sleep deprivation and can take precautions accordingly. An insomniac can tell if the symptoms are severe and will think twice before getting behind the wheel. It is unlikely that a narcoleptic is legally permitted to drive. By contrast, subjects with undiagnosed apnea (almost 90% of cases) are unaware of not having slept well and this causes them to be much more vulnerable to accidents both in the car and at work.
Scientific studies on sleep apnea and the accident rate
Studies on the link between accidents and OSAHS go back to the 1980s. One of the most important articles was carried out by Findley et al. They demonstrated a higher level of accidents in a group of patients with OSAHS. More than twenty years later the increased risk of accidents is known to be between 300% and 400% higher that that of a healthy population. Although these statistics have been known for more than a decade, the problem is yet to be taken seriously. In 1998, Barbé et al studied 60 OSAHS patients with a control group of 60 healthy individuals (matched age and gender) in order to quantify the number of road traffic accidents over the previous three years. Patients with OSAHS had more accidents than control subjects and were at greater risk of suffering more than just one accident. OSAHS sufferers were also found to be more sleepy, more anxious and more depressed than the control group and were less vigilant whilst driving. Teran-Santos et al. selected 102 drivers who were treated in the accident and emergency departments of Burgos and Santander hospitals following road traffic accidents. The results confirm the strong link between sleep apnea, measured by the Apnea/Hypopnea Index (AHI≥ 10), and traffic accidents after taking into account other possible causes of accidents such as alcohol consumption, visual impairment, Body Mass Index (BMI), driving experience, age, history of traffic accidents, use of medications which cause drowsiness and haphazard sleep patterns. OSAHS represents a greater risk factor than other common causes of accidents such as visual or hearing defects, rheumatic heart disease, diabetes, neurological diseases, alcoholism, drug abuse or mental illness. Alcohol consumption in conjunction with sleep apnea explains the vast majority of accidents caused by the human factor. Poor sleep quality is responsible for behavioural changes, irritability, cognitive impairment, decreased motor and sensory functions and reduced attention span. All of these factors have a negative effect on the everyday task of driving. According to the Department of Motor Vehicles (Spain), up to 20% of accidents are related to drowsiness, making it comparable to the amount of accidents caused by alcohol consumption or excessive speed.