Background. Sleepiness and reduced vigilance are important risk factors for road accidents. In the Philippines, accidents were caused by driver error, drunk driving, vehicle mechanical defects, speeding, and use of cell phone while driving represented the highest increase among causes of vehicular accidents. No data on sleep related disorder was presented as one of the causes of vehicular accidents. It is the goal of this paper to determine if the severity of sleep apnea is a factor contributing to the incidence of vehicular accidents among patients diagnosed with obstructive sleep apnea in Philippine Heart Center Sleep Clinic.
Methods. A cross sectional study was done on patients diagnosed with sleep apnea syndrome from January 2005 up to December 2011 in the Philippine Heart Center Sleep Clinic through polysomnography. They were interviewed regarding driving and driving accidents.
Results. There were 361 patient drivers included in the study. Among these patient drivers, 62 (17%) were noted to have mild sleep apnea syndrome, 63 (17.45%) were moderate SAS and 236 (65.37%) severe SAS patients. It was noted that the driving accidents tend to increase in number as the severity of SAS increases (mild SAS= 48.38% (30/58), moderate SAS=52.38% (33/63), severe SAS=58.47% (138/236). However, the incidence of driving accidents across the 3 groups of SAS did not differ significantly. Majority of the SAS patients gave"sleepiness" as the reason in 86.06% of the respondents. Other causes were "not following traffic rules" in 12.94%, alcohol intake (8.96%), attributed to other's fault in 6.97%, personal human error (4.97%) and cell phone use (0.5%). By statistical analysis, the reasons of driving accidents were not significantly associated to the severity of SAS.
Conclusions. The study showed that driving accidents occurred more than 50% of SAS patients regardless whether the severity was mild, moderate or severe. The incidence of driving accidents tends to increase with increasing severity of SAS. This, however, was not statistically significant.