Patients with obstructive sleep apnoea syndrome (OSAS) have an increased car accident rate. Investigations on accident frequency are based on case history, insurance reports and driving simulator studies. The present study combines neuropsychological testing of different attention aspects engaged in driving a car and driving simulation to evaluate a suitable instrument for assessing therapeutic effects of continuous positive airway pressure (CPAP).Driving simulator investigation and neuropsychological testing of alertness, vigilance and divided attention were performed in 31 patients with polysomnographically confirmed OSAS (apnoea-hypopnoea index 24.8¡21.5?h -1 ) before, and 2 and 42 days after initiation of CPAP. Divided attention and alertness improved significantly during CPAP, whereas vigilance remained unchanged. However, accident frequency (OSAS before therapy: 2.7¡2.0; 2 days after CPAP: 1.5¡1.4; 42 days after CPAP: 0.9¡1.3) and frequency of concentration faults (OSAS before therapy: 12.4¡5.1; 2 days after CPAP: 6.5¡3.9; 42 days after CPAP: 4.9¡3.3) decreased in the simulated driving situation after 2 and 42 days of therapy. There was no relation between accident frequency, concentration faults and daytime sleepiness, as measured by the Epworth Sleepiness Scale, and polysomnographic or neuropsychological findings, respectively.In conclusion, the present results suggest that driving simulation is a possible benchmark parameter of driving performance in obstructive sleep apnoea syndrome patients.

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An increased cardiovascular event rate in elderly patients under opioid medications was recently reported. One reason for this increase could be the occurrence of nocturnal apnea and hypoxia, as a consequence of sleep-disordered breathing (SDB). Using a controlled study, we prospectively analyzed SDB using polysomnography in a total of 18 patients before and after opioid withdrawal (opioid withdrawal group [OG]) and 14 patients before and after comprehensive pain management (without any strong-acting opioids) who served as the control group (CG). To analyze the differences, unpaired/paired t tests and Mann-Whitney U tests/Wilcoxon rank tests were used. At baseline, the OG presented more nocturnal apneas/hypopneas than the CG with an apnea-hypopnea index (AHI) of 41.4 ± 27.8 vs 21.8 ± 15.9 (P = 0.018). After treatment, the AHI decreased significantly only in the withdrawal group (OG: 16.7 ± 8.9; CG: 20.1 ± 12.9) (P < 0.01). Before treatment, none of the CG but half of the OG patients showed central apnea, which disappeared afterwards. A mean O2 saturation during rapid eye movement sleep lower than 90% was found in 27.5% of the OG patients before opioid withdrawal and in none of the patients after withdrawal (P < 0.01). The AHI was not significantly affected by body mass index, age, or sex. Obviously, nocturnal apnea and O2 desaturation occurred more frequently, as was clinically expected in patients with opioid intake; these findings may explain the opioid-associated cardiovascular morbidity. Thus, SDB may be a risk at lower opioid doses than hitherto described, and particular caution should be exercised in patients with comorbidities that might make them vulnerable to the consequences of SDB.

Theophylline is effective in the treatment of central apneas and periodic breathing. In obstructive sleep apnea syndrome (OSAS), results of pharmacological monotherapy with theophylline are inconsistent. The present study investigates whether additional theophylline in patients with OSAS and continuous positive airway pressure (CPAP) therapy might improve ventilation, lower effective CPAP pressure levels or affect sleep architecture. Patients with mild to moderate OSAS (mean apnea index [AI] 12.8+/-11.7) and CPAP therapy (Autoset system; n=16, all male) received either 900 mg of oral sustained-release theophylline (T) or placebo (P) on two separate nights, 3 days apart, using a randomized double-blind crossover study design. There was no change in AI (T: 0.7+/-1.4 vs. P: 0.7+/-0.6/h; P=0.3) or apnea-hypopnea index (AHI; T: 4.3+/-3.3 vs. P: 4.5+/-3.7/h; P=0.84) when theophylline was added to CPAP therapy. We observed no difference in mean CPAP pressure (T: 6.9+/-2.1 vs. P: 6.7+/-1.9 cm H2O; P=0.7) or 95% pressure percentiles (T: 9.7+/-2.7 vs. P: 9.3+/-2.1cm H2O; P=0.3) when nights with theophylline were compared to placebo nights. Theophylline reduced significantly total sleep time (T: 290.6+/-58.9 vs. P: 338.0+/-40.1 min; P=0.02) and thus sleep efficiency (SE; T: 70.5+/-14.9%, P: 82.0+/-70.5%; P=0.005). Rapid eye movement and slow wave sleep were not affected. Oral theophylline did not show any additional effects on ventilation parameters or pressures in patients with mild to moderate OSAS once CPAP therapy has been successfully installed. SE was reduced with theophylline with unchanged sleep architecture. The role of oral theophylline may be in patients with predominately central apneas not eligible for ventilation therapy or severe cases.