Objective: Narcolepsy management usually requires lifelong pharmacotherapy. However, we know little about adherence to prescribed treatment in narcolepsy. We assessed adherence to wakefulness-promoting agents in narcolepsy patients.
Patients and methods: We retrospectively assessed adherence to wakefulness promoting medication in patients with narcolepsy using the Medicines Possession Ratio (MPR). Three levels of adherence were defined: poor (≤50%), intermediate (51-79%), and good (≥80%). Refractory daytime sleepiness was defined as an Epworth sleepiness scale (ESS) score >12 despite trialling at least three wakefulness-promoting agents. We compared demographic and clinical factors, and prescribed medications between patients, stratified by levels of adherence, as well as by presence or not of refractory sleepiness.
Results: We included 116 patients with narcolepsy (54.3% female, mean age 39.4 (±14) years). In sum, 93 (80.2%) patients had a diagnosis of narcolepsy type 1 (NT1), and 23 (19.8%) of type 2 (NT2). Suboptimal symptom control was common: 39.8% had refractory sleepiness, and 47.3% of NT1 patients had persistent cataplexy. Good adherence was seen in only 55.2% of patients, while 12.9% were intermediately and 31.9% poorly adherent. Patients with poor adherence were more likely to have a diagnosis of NT2, but adherence did not vary according to gender, age, the presence of psychiatric co-morbidity, or the presence of apparent intractable symptoms. Levels of good adherence to therapy were no better in patients with refractory sleepiness than in those with satisfactory symptom control (56.5% vs 54.3%; p = 0.81).
Conclusion: Suboptimal adherence to prescribed therapy is common in narcolepsy patients, including those with apparent intractable symptoms, and particularly in patients with NT2.
Keywords: Adherence; Narcolepsy; Sleepiness; Wakefulness-promoting medication.
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