Study objectives: Nasal continuous positive airway pressure (nCPAP) usually reduces sleepiness in patients with obstructive sleep apnea/hypopnea syndrome. However, even with regular use of nCPAP, some patients experience residual excessive sleepiness. We evaluated the efficacy and safety of the wake-promoting agent modafinil for treating residual excessive sleepiness in nCPAP-treated patients.
Design: 12-week, multicenter, randomized, double-blind, parallel-group, placebo-controlled trial.
Patients: Patients aged 18 to 70 years diagnosed with obstructive sleep apnea/hypopnea syndrome and having residual excessive sleepiness during nCPAP therapy were eligible.
Interventions: Once-daily modafinil, 200 mg or 400 mg, or placebo.
Measurements and results: Assessments included the Maintenance of Wakefulness Test, Epworth Sleepiness Scale, Clinical Global Impression of Change, and Functional Outcomes of Sleep Questionnaire. Both doses of modafinil significantly improved mean (SD) sleep latency on the Maintenance of Wakefulness Test at weeks 4, 8, and 12 compared with placebo (week 12: modafinil 400 mg, 15.0 [5.3] minutes; 200 mg, 14.8 [5.3] minutes; placebo, 12.6 [5.8] minutes; P < .0001). The Epworth Sleepiness Scale score decreased more in patients taking modafinil compared with those in the placebo group (week 12: modafinil 400 mg, -4.5 [4.3]; 200 mg, -4.5 [4.7]; placebo, -1.8 [3.5]; P < .0001). At week 12, overall clinical condition improved for 61% and 68% of patients treated with modafinil 200 mg and 400 mg, respectively, versus 37% of placebo-treated patients (P < .001). Modafinil was generally well tolerated and did not adversely affect nighttime sleep or nCPAP use.
Conclusions: These results confirm previous shorter-term controlled trials, indicating modafinil is a useful adjunct therapy for improving wakefulness in patients with residual excessive sleepiness associated with obstructive sleep apnea/hypopnea syndrome who were treated with nCPAP.