Table 1.
Characteristics of studies that evaluated CPAP and crash risk
| Year | No. of Individuals in study (n = ) | Study design | Age Distribution | AHI (SD) | Mean BMI (SD) | Mean ESS (SD) | % Male | Factors controlled for (if compared to controls) | Driving Exposure | Definition of Crash | Crash data objective? | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Barbe et al.27 | 2006 | 80 | Before-After + case-control* | 49 years (SEM: 1) | >20 per hour | 33 kg/m2(SEM: 0.7) | 12 (SEM: 1.0) | 97.5 | Age, sex, alcohol consumption | 25,000 km/year (SEM: 2,000) | Accident resulting in property damage > $500 and/or personal injury | No |
| George et al.28 | 2001 | 210 | Before-After + case-control* | 51 years (11) | 54 per hour (29) | 35.5 kg/m2(10) | NR | NR | Age, sex, driver class | 22,700 km/year (16,500) | NR | Yes (MTO data) |
| Findley et al.29 | 2000 | 36 | Before-After + case-control* | 54 years (SEM: 2) | 37.9 per hour (SEM: 5.0) | NR | NR | 83.3 | Age, sex | NR | Accident resulting in property damage > $500 or personal injury for which the driver was convicted of a traffic violation | Yes (State DMV records) |
| Horstmann et al.30 | 2000 | 71 | Before-After | NR | NR | NR | NR | NR | NA | 17,784 km/year | Accident causing material damage or personal injury | No |
| Yamamoto et al.32 | 2000 | 39 | Before-After | 49.5 years (10.8) | 29.2 kg/m2 (5.4) | 12.6 (4.9) | 100.0 | NA | NR | NR | No | |
| Scharf et al.31 | 1999 | 316 | Before-After | 48.8 years (SEM: 0.7) | 42.9 per hour (SEM: 1.7) | NR | NR | 74.1 | NA | NR | NR | No |
| Krieger et al.33 | 1997 | 893 | Before-After | 56.6 years (10.7) | 34.9 per hour (21.1) | 33.7 kg/m2(6.8) | NR | 86.5 | NA | NR | NR | No |
| Cassel et al.34 | 1996 | 78 | Before-After | 48.0 years (SEM:1.0) | 34.2 per hour (SEM: 3.1) | 31 kg/m2(SEM: 0.6) | NR | 100.0 | NA | 29,606 km/year (SEM: 2,367) | NR | No |
| Engelman et al.35 | 1996 | 253 | Before-After | 46 years (9) | 47 (38) | NR | 15.6 (6.0) | NR | NA | NR | Minor (not injurious) and major (causing injury) | No |
AHI, Apnea-hypopnea index; BMI body mass index; CPAP, continuous positive airway pressure; DMV, department of motor vehicles; ESS, Epworth Sleepiness Scale; MTO, Ministry of Transportation of Ontario; NA, not applicable; NR, not reported; SD, standard deviation; SEM, standard error of the mean. Study included a control group; however, for the purposes of this analysis the study is a before-after study (see text).