Navigation Links
Study finds that using wakefulness tests to detect daytime sleepiness in drivers may be unreliable
Date:2/14/2009

Westchester, Ill. A study in the Feb. 15 issue of the Journal of Clinical Sleep Medicine shows that a 40 minute protocol for the Maintenance of Wakefulness Test (MWT40) is superior to a 20-minute protocol (MWT20) at detecting excessive daytime sleepiness (EDS) in adults who may be unable to maintain wakefulness while driving. Yet results also suggest that the test may not be completely reliable when the strong motivation to keep a driver's license enables individuals to overcome sleepiness during the test.

Forty-one out of the 164 subjects in the study (25 percent) fell asleep in one or more of the MWT40 trials; 10 participants (6.1 percent) fell asleep in all four trials. Out of 39 subjects with severe obstructive sleep apnea (OSA), 19 (48.7 percent) fell asleep in at least one of the trials. In a previous study of the MTW20 protocol, only five out of 54 subjects (9.2 percent) fell asleep in any of the trials.

According to the principal investigator Giora Pillar, M.D, Ph.D, with the Sleep Laboratory at Rambam Medical Center in Haifa, Israel, it is very difficult to objectively assess and quantify the capability of an individual to remain vigilant. Many of the study's participants may have been highly motivated to overcome their sleepiness during the test in order to prevent their license from being revoked.

"It could be expected that the MWT40 will be superior to MWT20, but it is somewhat surprising that despite a strong drive to sleep, as in cases of severe apnea, people could pass the test by remaining awake in all trials," said Pillar. "It emphasizes the strong effect of motivation."

The study included 164 consecutive subjects with an average age of 50, who were referred to the Technion Sleep Lab between June 2006 and January 2007 by the Medical Institute for Driving Safety of the Ministry of Transportation. Participants who were suspected of suffering from EDS were referred for evaluation for their ability to maintain wakefulness for the purpose of renewal of their license to drive. Seventeen of the participants were professional drivers and one participant was an aviation pilot.

All subjects underwent a full-night polysomnograph followed by an MWT40, (four 40 minute long trials). During the MWT, participants were told to sit on a bed in a reclining position in a private, dimly lit room. Subjects were not allowed to perform any unusual action to maintain wakefulness, such as reading, talking, consuming caffeine or making repetitive movements. Trials were stopped if the subject fell asleep or if 40 minutes had passed.

According to Pillar, none of the participants who were receiving continuous positive airway pressure (CPAP) treatment failed the MWT 40; this information emphasizes the importance of treating OSA in preventing auto accidents caused by EDS. Pillar noted that findings of this study indicate that further research is necessary in order to determine a more efficient way to objectively assess an individual's ability to remain vigilant while driving.

According to the American Academy of Sleep Medicine (AASM), OSA is a sleep-related breathing disorder that involves a decrease or complete halt in airflow despite an ongoing effort to breathe. It occurs when the muscles relax during sleep, causing soft tissue in the back of the throat to collapse and block the upper airway. This leads to partial reductions (hypopneas) and complete pauses (apneas) in breathing that can produce abrupt reductions in blood oxygen saturation. Brief arousals from sleep restore normal breathing but can cause a fragmented quality of sleep. Most people with sleep apnea snore loudly and frequently, and they often experience excessive daytime sleepiness.

AASM practice parameters for the MWT recommend the 40-minute protocol and advise that the MWT be used when sleep clinicians require objective data to assess an individual's ability to remain awake. The MWT should be used in association with the clinical history to assess the ability to maintain wakefulness.


'/>"/>

Contact: Kelly Wagner
kwagner@aasmnet.org
708-492-0930
American Academy of Sleep Medicine
Source:Eurekalert

Related medicine news :

1. Study finds behavioral link between insomnia and tension-type headaches
2. IMPACT Study Demonstrates That Longer Prophylactic Therapy With Valcyte(R) (Valganciclovir Hydrochloride Tablets) Increases Protection Against CMV - the Most Serious Viral Infection Affecting Transplant Patients
3. Sponsor Dollars Key to Flu Vaccine Study Publication
4. Tobacco Companies Targeting Teens, Study Says
5. New CDC Study Shows Tobacco Marketing Influences Kids to Smoke, Underscores Need for FDA Regulation of Tobacco Products
6. Caregivers not receiving the help they need, study shows
7. Study Brings Value of Echocardiography Into Focus
8. Innerscope Research(TM) Names Caleb Siefert as Senior Scientist to Lead Companys Statistical Analyses and Study Designs
9. UNC study hints at new approaches to prevent transplant rejection
10. Higher blood sugar levels linked to lower brain function in diabetics, study shows
11. Peregrine Pharmaceuticals Bavituximab Achieves Primary Endpoint in First Stage of Phase II Breast Cancer Study
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/24/2016)... TX (PRWEB) , ... June 24, 2016 , ... People ... part in Genome magazine’s Code Talker Award, an essay contest in which patients and ... an award to be presented at the 2016 National Society of Genetic Counselors (NSGC) ...
(Date:6/24/2016)... York, NY (PRWEB) , ... June 24, 2016 ... ... publication Haute Living, is proud to recognize Dr. Barry M. Weintraub as a ... that “the most beautiful women in the world, and the most handsome men, ...
(Date:6/24/2016)... ... June 24, 2016 , ... ... feeding the Frederick area economy by obtaining investment capital for emerging technology companies. ... 2½ years that have already resulted in more than a million dollars of ...
(Date:6/24/2016)... ... , ... Venture Construction Group (VCG) sponsors Luke’s Wings ... the Woodmont Country Club at 1201 Rockville Pike, Rockville, Maryland, 20852. The event ... that have been wounded in battle and their families. Venture Construction Group is a ...
(Date:6/24/2016)... ... June 24, 2016 , ... ... upcoming 2016 Miss Arizona pageant as its official Medspa Sponsor. Dr. Josh Olson, ... and Chandler, Arizona. , Dr. Olson says the decision to support the ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... ANDOVER, Mass. and SAN CLEMENTE, Calif. ... California -based mobile pulmonary function testing company, is now ... portable PFT devices developed by ndd Medical Technologies , Inc. ... PFT testing done in hospital-based labs.  Thanks to ndd,s EasyOne PRO ... CA , can get any needed testing done in the ...
(Date:6/24/2016)... 24, 2016   Pulmatrix, Inc ., (NASDAQ: ... inhaled drugs, announced today that it was added to ... its comprehensive set of U.S. and global equity ... an important milestone for Pulmatrix," said Chief Executive Officer ... of our progress in developing drugs for crucial unmet ...
(Date:6/23/2016)... 23, 2016  MedSource announced today that it ... software solution of choice.  This latest decision demonstrates ... to their clients by offering a state-of-the-art electronic ... establishes nowEDC as the EDC platform of choice ... clients.  "nowEDC has long been a preferred EDC ...
Breaking Medicine Technology: