Philips Electronics today announced the results of an extensive new scientific study into sleep apnea, conducted over the last two years by Philips in collaboration with University of Twente (Enschede, the Netherlands), Medisch Spectrum Twente Hospital (Enschede, the Netherlands), and patients' organization ApneuVereniging.The study, which surveyed 4,206 Philips employees in the Netherlands, revealed that 6.4% of them suffered from sleep apnea. A striking finding was that 78% of the people surveyed who reported symptoms of sleep apnea were entirely unaware that they were suffering from this sleep disorder.
Despite that fact that many people are unaware that they suffer from sleep apnea, the condition can have serious consequences for their health. It is also not difficult to treat. The aim of the study was therefore to gather up-to-date scientific information about how often sleep apnea, the commonest form of which is Obstructive Sleep Apnea Syndrome (OSAS) caused by obstruction of the upper airway, occurs. For decades, a high incidence of sleep apnea under-diagnosis has been suspected by doctors and scientists. The study was therefore designed to identify the number of people who were suffering from the condition but were unaware of it and not receiving treatment for it.
Never before has research into sleep apnea been conducted among such a large group of people. 29% of all Philips employees in the Netherlands took part in the study, comprising men and women of different ages and levels of education, with different types of job and different cultural backgrounds. Previous screening studies were based on considerably smaller populations. For example, an often cited study published in 1993 examined a group of 602 people. It was estimated in this study that 2% of women and 4% of men in the middle-aged work force suffer from sleep apnea.
Sleep apnea is a condition in which a person's breathing either pauses or becomes extremely shallow during sleep, with a frequency varying from five to more than thirty times an hour. According to Dr. Michiel Eijsvogel, pulmonologist at the Medisch Spectrum Twente Hospital, who was involved in the study, many people suffer from sleep apnea without being aware of it.
"That's more dangerous than you might think," he says. "Due to the disruption it causes to their sleep patterns they get less rest at night, become tired, are sleepy during the day, perform increasingly poorly at work and have a quick temper. They often attribute symptoms to stress or pressure. The disorder increases their chances of suffering from high blood pressure, diabetes and cardiovascular disease, so it is very important that these people get help. Through this study we will find out more about the nature and extent of the disorder. This has positive consequences for people with sleep apnea. By increasing awareness of the characteristics of the condition, patients and family physicians may react more alertly to symptoms, resulting in faster referral and treatment."
Piet-Heijn van Mechelen, Chair of Dutch patient organization ApneuVereniging and Project Leader for the survey, is pleased that the study has produced clear results.
"Hundreds of thousands of people have symptoms but don't know what the problem is," he says. "This study provides valuable new insights into how often the condition occurs. And with the new screening method that was developed for this study, sleep apnea can be identified at an earlier stage and the quality of life of patients suffering from the condition can be greatly improved with treatment."
The sleep survey took almost two years to complete and consisted of two phases: a preliminary survey to develop and validate a new scientific questionnaire, followed by the main survey.