Predictors of long-term effectiveness to mandibular repositioning device treatment in obstructive sleep apnea patients after 1000 days

•Two-thirds of OSA patients were still using the MRD device, 1000 days after treatment initiation.•Short-term efficacy was predictive of long-term adherence.•Relapse of nocturia may be an early signal of MRD wear.

Objective/backgroundIn obstructive sleep apnea (OSA), long-term adherence to treatment is crucial. This prospective single-center study investigated factors associated with long-term adherence to mandibular repositioning device (MRD) therapy.Patients/methodsAll OSA patients who had MRD treatment initiated in the previous year were prospectively contacted to evaluate long-term effectiveness and compliance. Long-term adherence was based on continuation of treatment (yes/no). Predictors of long-term adherence were analyzed using an adjusted multivariate analysis.ResultsMedian follow-up was 1002 days (interquartile range: 668-1345) in 279 patients (age 58 [50-64] years); 63% of patients were continuing MRD treatment with a good efficacy, tolerability and compliance over time. In some patients, relapse of nocturia was observed while efficacy was maintained for snoring and somnolence. In adjusted multivariate analysis, significant predictors of continuing MRD treatment were early ≥50% reduction in AHI (odds ratio [OR] 2.73, 95% confidence interval [CI] 1.466-5.10; p = 0.0002) and complete symptom resolution (OR 3.83, 95% CI 1.74-8.48; p = 0.0014). In the 37% of patients who stopped MRD treatment, median treatment duration was 351 (174-752) days. The main reasons for late stopping of treatment were inefficacy (26.2%), discomfort (25.2%) and side effects (21.4%).ConclusionsAfter three years, MRD was effective for the two-thirds of OSA patients who continued treatment. Relapse of nocturia might be an early signal of MRD wear that may explain long-term cessation of treatment in some patients. Short-term control of OSA by MAD was predictive of long-term efficiency. The major criteria were a ≥50% reduction in AHI and complete symptom resolution at short-term evaluation.