Table 2.
Risk factors for automobile accidents caused by falling asleep while driving OSAS patients
| Univariate | Multivariate logistic regressiona | |||||
|---|---|---|---|---|---|---|
| OR | 95%CI | P | OR | 95%CI | P | |
| Age (years old) | 0.99 | 0.98–1.00 | <0.01 | NS | ||
| AHI (/h) | 1.01 | 1.00–1.02 | <0.01 | 1.08 | 1.048–1.114 | NS |
| Epworth sleepiness scale | 1.13 | 1.10–1.16 | <0.01 | <0.01 | ||
| BMI (kg/m2) | 1.05 | 1.02–1.07 | <0.01 | NS | ||
| Smoker | NS | |||||
| Alcoholic use | NS | |||||
| Sleep latency (min) | 0.98 | 0.97–0.99 | <0.01 | NS | ||
| Minimum SpO2 | 0.98 | 0.97–0.99 | <0.01 | NS | ||
| 3%ODI (/h) | 1.01 | 1.01–1.02 | <0.01 | |||
| 4%ODI (/h) | 1.01 | 1.00–1.02 | <0.01 | |||
| Arousal index (/h) | 1.01 | 1.01–1.02 | <0.01 | |||
| Leg movement index (/h) | NS | |||||
| Habitual sleep time (/h) | NS | |||||
| Irregular shift worker | NS | |||||
| Driving distance/month; longer than 1000 km | 1.76 | 1.35–2.28 | <0.01 | NS | ||
| Frequency of feeling drowsiness during regular driving and working; more than sometimes | 3.31 | 2.45–4.48 | <0.01 | 1.98 | 1.40–2.81 | <0.01 |
| Gender | NS | |||||
Driving distance/month and the frequency of feeling drowsy during regular driving and working were divided into two groups around the median. We performed multivariable analysis by the combinations of the following four patterns (set1 + AHI, set1 + arousal index, set1 + 3%ODI, set1 + 4%ODI). Set1 included age, Epworth sleepiness scale, BMI, sleep latency, minimum SpO2, driving distance/month: longer than 1000 km and frequency of feeling drowsiness during regular driving and working, more than sometimes
ODI oxygen desaturation index, OSAS obstructive sleep apnea syndrome, OR odds ratio, CI confidence interval, AHI apnea-hypopnea index, BMI body mass index
aBecause the AHI strongly correlated with arousal index (r = 0.881), 3%ODI (r = 0.966), and 4%ODI (r = 0.943), multivariable analysis were performed these factor separately