Sodium Oxybate for Narcolepsy with Cataplexy: Systematic Review and Meta-Analysis

University Sleep Disorders Center, King Saud University, Riyadh, Saudi Arabia.
Journal of clinical sleep medicine: JCSM: official publication of the American Academy of Sleep Medicine (Impact Factor: 3.05). 08/2012; 8(4):451-8. DOI: 10.5664/jcsm.2048
Source: PubMed


To assess the efficacy and safety of sodium oxybate (SXB) in narcolepsy-cataplexy patients.
Systematic review and meta-analysis.
Adults with narcolepsy-cataplexy.
Electronic databases (e.g., MEDLINE) and references of included studies were searched to identify randomized controlled trials (RCTs) assessing the efficacy and safety of SXB for patients with narcolepsy-cataplexy. Risk of bias was appraised using the Cochrane risk of bias tool. Meta-analysis was conducted in Review Manager Version 5. Six RCTs and 5 companion reports were included after screening 14 full-text articles and 483 citations. All were private-industry funded. SXB (usually 9 g/night) was superior to placebo for reducing mean weekly cataplexy attacks (n = 2 RCTs, mean difference [MD]: -8.5, 95% CI: -15.3, -1.6), increasing maintenance wakefulness test (MWT) (n = 2, MD: 5.18, 95% CI: 2.59-7.78), reducing sleep attacks (n = 2, MD: -9.65, 95% CI: -17.72, -1.59), and increasing Clinical Global Impression scores (n = 3, relative risk, RR: 2.42, 95% CI: 1.77-3.32). SXB did not significantly increase REM sleep versus placebo (n = 2, MD: -0.49, 95% CI: -3.90, 2.92). Patients receiving SXB had statistically more adverse events versus placebo, including nausea (n = 3, relative risk [RR]: 7.74, 95% CI: 3.2, 19.2), vomiting (n = 2, RR: 11.8, 95% CI: 1.6, 89.4), and dizziness (n = 3, RR: 4.3, 95% CI: 1.1, 16.4). Enuresis was not significantly different from placebo (n = 2, RR: 2.6, 95% CI: 0.8, 9.8). All meta-analyses had minimal statistical heterogeneity (p-value > 0.1).
Narcolepsy patients on SXB have significant reductions in cataplexy and daytime sleepiness. SXB is well tolerated in patients with narcolepsy, and most adverse events were mild to moderate in severity.


Available from: Ahmed Salem BaHammam, Jun 30, 2014
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