Assessment of interfering factors in non-adherence to oral appliance therapy in severe sleep apnea

Objective Oral appliances (OA) are recommended for patients with severe obstructive sleep apnea who fail to comply with continuous positive airway pressure (CPAP) therapy. This mixed-methods study aimed to quantify adherence to OA therapy and evaluate subjective reasons associated with non-adherence. Materials and Methods The medical records of 52 patients with an apnea-hypopnea index (AHI) ≥ 40, treated with OA after discontinuation of CPAP treatment, were examined for OA adherence. Patients were divided according to usage at the time of a phone interview. The USER group included all forms of usage, whereas those who completely ceased using the OA were in the NUSE group. The timing of the phone interview was from five months to six years (average 44.63 ± 17.17 months) after OA delivery. Results The overall adherence rate was 57.7% (30/52 patients). The mean usage times were 10.07 ± 8.96 and 44.30 ± 17.3 months in the NUSE and NUSE groups, respectively. The main factors associated with non-adherence were concerns about the effects of the OA on teeth (22%) and insufficient efficacy (22%). Other factors were discomfort (15%) and improved well-being following weight loss (15%). The overall number of interfering and discontinuity factors was significantly higher in the NUSE group than in the USER group (P = 0.041). Nine (17.3%) of 52 patients resumed CPAP use. Subjective and objective outcomes, determined by using a second sleep test with OA in 69.2% of patients, were related to the continuation of treatment. Conclusions On-adherence to OA is strongly associated with patient reservations regarding the effects of the device on teeth, possible lack of efficacy, and discomfort. Clinicians should closely monitor adherence patterns and assess potential interfering factors during their diagnostic workup. Patients should be reassured regarding device safety, particularly following dental work that may interfere with the insertion of the OA.