Adherence to Continuous Positive Airway Pressure in patients with Obstructive Sleep Apnoea. A ten year real life study

Objective: To assess the predictive factors at 12 month and 10 year adherence to Continuous Positive Airway Pressure (CPAP) in patients with Obstructive Sleep Apnoea (OSA). Methods: Retrospective data analysis of patients starting CPAP between 2006 and 2009. After 12 months (T1) from start and during a 10 year follow up the following data were recorded: Body Mass Index (BMI), Time of night use, Epworth Sleepiness Scale (ESS) score. Results: Out of 315 patients, 147 fulfilled inclusion criteria and were evaluated. According to CPAP nighttime use during the first year, patients were divided into two groups: those using the device less < 4.5 h (Poor Adherence (PA): 61 patients), and those using ≥4.5 h: (Good Adherence (GA): 86 patients). Patients of PA group were significantly younger, had greater BMI and required more unscheduled visits during the first year. After 12 months, there were 11 (7.5%) dropouts, all in PA group. Patients using the nasal mask showed a greater prevalence among GA as compared to those using the oro-nasal mask (76.5% vs 57.8% respectively, p = 0.04). After 10 years 83 out of 147 (56.4%) patients were still under CPAP, 51 (59.3% of GA) and 32 (52.4% of PA group) respectively. Dropouts were significantly more frequent during the first 5 years (p = 0.04). Conclusion: Ten years after prescription the majority of patients with OSA undergoing periodical controls, still perform CPAP independent of their adherence to therapy after one year of use. Use of nasal mask may be associate to better adherence.