We used meta-analysis to synthesize current evidence regarding the
effect of nasal continuous positive airway pressure (nCPAP) on road
traffic accidents in patients with obstructive sleep apnea (OSA) as well
as on their performance in driving simulator. The primary outcomes were
real accidents, near miss accidents, and accident-related events in the
driving simulator. Pooled odds ratios (ORs), incidence rate ratios
(IRRs) and standardized mean differences (SMDs) were appropriately
calculated through fixed or random effects models after assessing
between-study heterogeneity. Furthermore, risk differences (RDs) and
numbers needed to treat (NNTs) were estimated for real and near miss
accidents. Meta-regression analysis was performed to examine the effect
of moderator variables and publication bias was also evaluated. Ten
studies on real accidents (1221 patients), five studies on near miss
accidents (769 patients) and six studies on the performance in driving
simulator (110 patients) were included. A statistically significant
reduction in real accidents (OR = 0.21, 95% Cl = 0.12-0.35, random
effects model: IRR = 0.45, 95% Cl = 0.34-0.59, fixed effects model) and
near miss accidents (OR = 0.09, 95% Cl = 0.04 -0.21, random effects
model; IRR = 0.23, 95% Cl = 0.08-0.67, random effects model) was
observed. Likewise, a significant reduction in accident-related events
was observed in the driving simulator (SMD = -1.20, 95% Cl = -1.75 to
-0.64, random effects). The RD for real accidents was -0.22 (95% Cl =
-0.32 to -0.13, random effects), with NNT equal to five patients (95%
Cl = 3-8), whereas for near miss accidents the RD was -0.47 (95% Cl =
-0.69 to -0.25, random effects), with NNT equal to two patients (95% Cl
= 1-4). For near miss accidents, meta-regression analysis suggested that
nCPAP seemed more effective among patients entering the studies with
higher baseline accident rates. In conclusion, all three meta-analyses
demonstrated a sizeable protective effect of nCPAP on road traffic
accidents, both in real life and virtual environment. (C) 2010 Elsevier
Ltd. All rights reserved