Clinical and polysomnographic characteristics of patients with REM sleep disordered breathing

There is a 10 -36% rate of obstructive sleep apnoea syndrome (OSAS) associated with rapid eye movement (REM) in the OSAS population. Prior studies have suggested an increased prevalence of psychiatric disorders and an effect of gender and age on these patients. Our aim was to study the clinical and polysomnograph (PSG) characteristics of our patients with REM- -related sleep disordered breathing (REM SDB). Inclusion criteria was the identification of REM SDB detected by PSG defined as apnea -hypopnea index (AHI) in REM sleep > or = 5h, AHI in non -REM sleep (NREM) < or = 15h and REM/NREM AHI > or = 2. Several Sleep Disorders Questionnaire (SDQ) version 1.02 parameters were analysed. The study comprised 19 patients with a mean age of 54.0 (SD+/-13.97), a mean BMI of 29.01 (SD +/- 4.10) and a 0.58 female / male ratio. The mean Epworth Sleepiness Scale score was 12.74 (SD +/-4.86). Mean AHI was 9.16/h (SD 4.09); mean AHI in REM sleep 37.08/h (SD 25.87) and mean REM -AHI/NREM- -AHI 8.86 (SD 8.63). The anxiety disorder rate was 33.3%; 44.4% in females, 16.7% in males. The average deep sleep was 20.7% (SD 10.42) and REM sleep 15.45% (SD 9.96), with a sleep efficiency of 85.3 (SD 8.70). No significant statistical correlation was found between the REM/NREM AHI index and anxiety symptoms, daytime sleepiness and sleep quality (REM and deep sleep percentages). These patients differ from the general OSAS population: on average, they are not obese, there are a greater number of females affected and they do not present a very significant diurnal hypersomnia. Reduced deep sleep and increased REM sleep were also present versus general population data, and sleep efficiency was just below the normal limit. Anxiety disorders were more prevalent in this group than described for the general population (3%) and OSAS patients.