Advanced emergency braking system reduces the risk of motor vehicle collisions caused by falling asleep while driving in patients with untreated obstructive sleep apnea.

Obstructive sleep apnea leads to excessive daytime sleepiness and cognitive dysfunction, which are risk factors for motor vehicle collisions. We aimed to clarify if vehicles with an advanced emergency braking system could reduce motor vehicle collisions caused by falling asleep while driving among patients with untreated obstructive sleep apnea. We enrolled patients with untreated obstructive sleep apnea who underwent polysomnography. The questionnaires included the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, history of drowsy driving accidents, and use of an advanced emergency braking system. Multivariate analysis was performed, and odds ratios and 95% confidence intervals were calculated. This study included 1097 patients (mean age, 51.2 ± 12.9 years). Collisions caused by falling asleep while driving were recorded in 59 (5.4%) patients, and were more frequently observed in vehicles without an advanced emergency braking system (p = 0.045). Multivariate analysis showed that these collisions were associated with use of an advanced emergency braking system (odds ratio [95% confidence interval]: 0.39 [0.16-0.97], p = 0.04), length of driving (2.79 [1.19-6.50], p = 0.02), total sleep time (2.40 [1.62-3.55], p < 0.0001), sleep efficiency (0.94 [0.90-0.98], p = 0.003) and periodic limb movement index (1.02 [1.01-1.03], p = 0.004). The collision risk caused by falling asleep while driving in vehicles with an advanced emergency braking system was significantly lower. This study indicates that advanced emergency braking systems may be a preventive measure to reduce motor vehicle collisions among patients with untreated obstructive sleep apnea.

Estimated respiratory arousal threshold in patients with rapid eye movement obstructive sleep apnea.

PURPOSE: Rapid eye movement (REM) obstructive sleep apnea (OSA) is a prevalent clinical phenotype. However, the literature focusing on the pathophysiology of REM OSA is limited. This study compared the proportion of individuals with a low respiratory arousal threshold between patients with REM and non-REM OSA. METHODS: REM OSA was defined as having an apnea-hypopnea index (AHI) ≥ 5 and AHI during REM (AHI-REM)/AHI during NREM (AHI-NREM) ≥ 2. REM OSA was sub-divided into REM-predominant OSA and REM-isolated OSA. REM-predominant OSA was defined as satisfying the definition of REM OSA and having an AHI-NREM ≥ 5. REM-isolated OSA was defined as satisfying the definition of REM OSA and having an AHI-NREM < 5. Patients with an AHI-REM/AHI-NREM < 2 were defined as having non-REM OSA. A low respiratory arousal threshold was defined as having 2 or more of the following conditions: AHI < 30 events/h, proportion of hypopnea > 58.3%, and nadir SpO2 > 82.5%. RESULTS: The proportions of individuals with low respiratory arousal thresholds among individuals with REM-predominant OSA and REM-isolated OSA were significantly higher (77.2% and 93.7%, respectively) than that of patients with non-REM OSA (48.6%). This was also true when the analysis was performed according to sex. CONCLUSION: These results indicate that a low respiratory arousal threshold might be an important endotype that contributes to the pathogenesis of REM OSA, especially in REM-isolated OSA.

Treatment outcome of oral appliance in patients with REM-related obstructive sleep apnea.

PURPOSE: Oral appliances (OA) are used to treat patients with obstructive sleep apnea (OSA). The purpose of this study is to evaluate the efficacy of OA treatment in patients with rapid eye movement (REM)-related OSA. METHODS: Forty-six patients with REM-related OSA and 107 with non-stage-specific OSA were prescribed OA treatment after diagnosis by polysomnography (PSG) and a follow-up sleep test by PSG was conducted. Efficacy and treatment outcome predictors were evaluated according to the following criteria for treatment success: #1, reduction of the apnea-hypopnea index (AHI) to less than 5 and > 50% compared with baseline; #2, AHI reduction to less than 10 and > 50% compared with baseline; and #3, > 50% AHI reduction compared with baseline. RESULTS: Success rates according to criteria #1, #2, and #3 were 45.7%, 50.0%, and 50.0% in REM-related OSA and 36.4%, 52.3%, and 63.6% in non-stage-specific OSA, respectively. No significant differences in success rate were found between the two groups. In multivariate logistic regression analysis with each criterion as the response variable, only BMI was extracted as a significant predictor. The BMI cutoff values defined based on the maximum Youden index according to the three criteria were 26.2 kg/m2, 25.6 kg/m2, and 26.2 kg/m2, respectively. CONCLUSIONS: No significant differences in success rate of OA treatment were found between REM-related OSA and non-stage-specific OSA. BMI has greater impact on treatment outcome of OA in patients with REM-related OSA.

Polysomnographic parameters during non-rapid eye movement sleep predict continuous positive airway pressure adherence.

The aim of this study was to investigate the potential polysomnographic predictors of CPAP adherence using polysomnographic parameters at the time of obstructive sleep apnea diagnosis that distinguished between REM and NREM sleep. This was a retrospective cross-sectional study of 173 patients. Patients who used CPAP for more than 4 hours per night for at least 70% of nights over a 6-month period were considered to have good adherence. The poor adherence group included those who had used CPAP for 6 months from initiation, but did not fulfill the definition of good adherence or gave up the treatment within 6 months of treatment initiation. Of the 173 participants, 44 patients had good CPAP adherence and 129 patients had poor adherence. Univariate analysis showed that patients with good adherence had significantly higher apnea-hypopnea index during NREM sleep (p = 0.043), oxygen desaturation index during NREM sleep (p = 0.011), and cumulative percentage of time spent at saturations below 90% (CT90) during NREM sleep (p < .001). In multiple logistic regression analysis including all variables, CT90 during NREM sleep was the only factor independently associated with CPAP adherence (odds ratio, 0.693; 95% confidence interval, 0.582-0.824; p <.0001). The area under the receiver-operating characteristic curve of CT90 during NREM sleep was 0.823 (95% confidence interval, 0.745-0.901).Evaluating NREM sleep is important in reliably predicting CPAP adherence using polysomnographic parameters. CT90 during NREM sleep was the best predictor of CPAP adherence.

Risk factors for automobile accidents caused by falling asleep while driving in obstructive sleep apnea syndrome.

PURPOSE: We examined the risk factors for automobile accidents caused by falling asleep while driving in subjects with obstructive sleep apnea syndrome (OSAS). METHODS: We asked licensed drivers with history of snoring and excessive daytime sleepiness who had undergone polysomnography (PSG) at the Department of Sleep Medicine/Sleep Disorders Center at Aichi Medical University Hospital to complete the questionnaires on accidents caused by falling asleep while driving. As a subjective measure of sleepiness, we used the Epworth sleepiness scale (ESS). Based on PSG results, 2387 subjects diagnosed with OSAS were divided into three groups according to apnea-hypopnea index (AHI): mild-to-moderate (5 ≤ AHI < 30), severe (30 ≤ AHI < 60), and very severe (AHI ≥ 60). We performed univariate and multivariate logistic regression on variables that might explain falling asleep at the wheel. RESULTS: We compared results between each group and simple snorers (394 subjects with AHI < 5) and found the group with very severe OSAS reported significantly higher rates of driving when drowsy and having accidents in the past 5 years due to falling asleep. CONCLUSIONS: Our multivariate analysis suggests that scores on the ESS and patient-reported frequency of feeling drowsy while regular driving and working are related to automobile accidents caused by falling asleep while driving.

[Polysomnography].

Polysomnography (PSG) is performed under monitoring each parameters include EEG derivations, EOG derivations, chin EMG, leg EMG derivations, airflow signals, respiratory effort signals, oxygen saturation, body position and EGG and checking digital video and audio. From these recordings, the sleep quality, sleep-disordered breathing, circulatory status and presence of parasomnia were evaluated. PSGs were based on the criteria "The AASM Manual for the Scoring of Sleep and Associated Events" published in 2007 detailed about technical specification and scoring rules for adult and pediatric. However, there are no specific criteria for the elderly. There already have been known about characteristics for the elderly such as lower amplitude of Δ wave in slow-wave sleep stage, PLMS and RWA in PSG.

Risk factors for collisions attributed to microsleep-related behaviors while driving in professional truck drivers.

Sleep-disordered breathing (SDB) is prevalent among professional drivers. Although SDB is a known risk factor for truck collisions attributed to microsleep-related behaviors at the wheel (TC-MRBs), the usefulness of overnight pulse oximetry for predicting TC-MRBs is debatable. This retrospective study assessed the association between overnight pulse oximetry parameters, the Epworth Sleepiness Scale (ESS), and TC-MRBs, confirmed by dashcam footage. This study included 108 matched professional truck drivers (TC-MRBs: N = 54; non-TC-MRBs: N = 54), with a mean age and body mass index of 41.9 ± 11.3 years and 23.0 ± 3.7 kg/m2, respectively. Night-time drivers, 4% oxygen desaturation index (ODI), and nadir oxygen saturation (SpO2) were associated with TC-MRBs (odds ratio [95% confidence interval]: 25.63 [5.88-111.77], p < 0.0001; 2.74 [1.02-7.33], p = 0.045; and 3.87 [1.04-14.39], p = 0.04, respectively). The area under the curve of 4% ODI and nadir SpO2 for TC-MRBs were 0.50 and 0.57, respectively. In conclusion, night-time driving, 4% ODI, and nadir SpO2 were significantly associated with TC-MRBs in professional truck drivers. However, the sensitivity of overnight pulse oximetry parameters to predict TC-MRBs in a real-world application was poor. Therefore, combining subjective and objective assessments such as dashcam video footage may be needed to achieve high accuracy for predicting TC-MRBs among professional truck drivers.

Association between pupillometric sleepiness measures and sleep latency derived by MSLT in clinically sleepy patients.

OBJECTIVES: The multiple sleep latency test (MSLT) has been employed extensively in clinical and research settings as a gold standard for objectively measuring sleepiness. In a general population or in a variety of work settings, however, a more convenient, rapidly administered measuring method is preferable. We examined the potential utility of pupillometry by comparing its objective measures, pupillary unrest index (PUI) and relative pupillary unrest index (RPUI), with MSLT-derived sleep latency (SL). METHODS: The study cohort comprised 45 patients (39 males, 6 females, mean age 38.9 ± 11.3 years) referred to the Sleep Disorders Center for the two-nap SL test. SL was measured twice before noon, and pupillometric measurement was performed immediately before each SL test. Subjective sleepiness was measured by using the Epworth Sleepiness Scale (ESS). RESULTS: The association between PUI and SL was significant and far closer than that between RPUI and SL. A significant difference was observed between the two groups, based on each subject's experience of drowsy driving accidents over the past 3 years in the PUI and RPUI, as well as in SL. The subjective sleepiness measure, ESS, did not relate to any other physiological sleepiness measures. CONCLUSIONS: In our study cohort, the pupillometric sleepiness measure, PUI, was significantly correlated with, and behaved in a manner equivalent to, MSLT-derived SL in clinically sleepy patients. However, several points remain to be carefully examined before applying pupillometry for screening sleepiness in a general population, or in occupational settings.

Dashcam video footage-based analysis of microsleep-related behaviors in truck collisions attributed to falling asleep at the wheel.

OBJECTIVE: With the rapid spread of dashcams, many car accidents have been recorded; however, behavioral approaches using these dashcam video footage have not been sufficiently examined. We employed dashcam video footage to evaluate microsleep-related behaviors immediately prior to real-world truck collisions in professional drivers to explore a new solution to reduce collisions attributed to falling asleep at the wheel. METHODS: In total, 3,120 s of video footage (60 s/case × 52 cases) from real-world truck collisions of 52 professional drivers obtained from interior and exterior dashcams were used and visually analyzed in a second-by-second manner to simultaneously evaluate any eye changes and microsleep-related behaviors (the driver's anti-sleepiness behavior, behavioral signs of microsleep, and abnormal vehicle behavior) during driving. RESULTS: Assessment of the frequency of occurrence of each item of microsleep-related behavior in the 52 collisions revealed that the item "touching" in terms of anti-sleepiness behavior, "absence of body movement" in terms of behavioral signs of microsleep, and "inappropriate line crossing" in terms of abnormal vehicle behavior were observed at the highest rate in all drivers (46.2%, 75.0%, and 78.8%, respectively). Decreases in anti-sleepiness behavior coincided with increases in behavioral signs of microsleep and abnormal vehicle behavior, with collisions occurring within approximately 40 s of these changes. Collisions were more common among young people and in the early morning and evening. CONCLUSION: Our dashcam video footage-based analysis in truck collisions attributed to falling asleep at the wheel revealed the process of changes in microsleep-related driver and vehicle behaviors, classified as anti-sleepiness behavior, behavioral signs of microsleep, and abnormal vehicle behavior. Based on these findings, to prevent collisions caused by falling asleep at the wheel, it is crucial to monitor not only the driver's eyes, but also the driver's whole body and vehicle behavior simultaneously to reliably detect microsleep-related behaviors.

Truck collisions attributed to falling asleep at the wheel in two commercial drivers prescribed oral appliance therapy for obstructive sleep apnea.

Falling asleep at the wheel is attributed to sleepiness, and obstructive sleep apnea is a significant cause of sleepiness that increases the risk of motor vehicle collisions due to falling asleep at the wheel. Although continuous positive airway pressure therapy for obstructive sleep apnea reduces the risk of motor vehicle collisions, similar evidence for alternatives such as oral appliance therapy is lacking. We discuss two truck collisions attributed to microsleep confirmed with dashcam video footage of commercial drivers with obstructive sleep apnea. Our results highlight the current situation where there is insufficient evidence for the prevention and reduction of the risk of motor vehicle collisions by oral appliance therapy, objective adherence monitoring of oral appliance therapy, and effectiveness confirmation tests. Therefore, it is suggested that for commercial truck drivers who require a high level of driving safety, careful selection for oral appliance therapy, systematic follow-up, and monitoring of the driver and truck status with dashcam video footage are crucial. CITATION: Kumagai H, Tsuda H, Kawaguchi K, et al. Truck collisions attributed to falling asleep at the wheel in two commercial drivers prescribed oral appliance therapy for obstructive sleep apnea. J Clin Sleep Med. 2023;19(12):2117-2122.

[A sleep disordered breathing as the lifestyle-related diseases].

Lifestyle related disease is a generic term for diseases such as cardiovascular diseases, diabetes mellitus and cancer caused by life style or life habit, and one of its fundamental causes is obesity. The reason why most people put on weight after their middle age is mainly because of the increase of visceral fat by the decrease in basal metabolism and the amount of momentum despite of unchanging appetite. Due to this sequence of weight gain, after middle age upper respiratory tract becomes narrower, and it worsens obstructive sleep apnea syndrome (OSAS). Since mastication is to provoke and maintain arousal, OSAS patients, who especially feel strong sleepiness, tend to encourage them to be obesity by frequent mastication that leads them to the tendency to overeat. Two main symptoms of OSAS are snoring and sleepiness; however, the essence of sleepiness is the worse quality of sleep due to apnea. In addition, a vicious circle is eventually generated because sleep deprivation and sleep disorders affects hypertension and glucose intolerance, and those worsen lifestyle disease. In order to break this off, it is necessary to review life style and habit, and improve not only on diet and exercise therapy but also on sleep.

Long-term outcomes regarding arterial stiffness and carotid artery atherosclerosis in female patients with rapid eye movement obstructive sleep apnea.

OBJECTIVE: Rapid eye movement (REM) obstructive sleep apnea (OSA) is associated with the risk of cardiovascular events. Arterial stiffness and carotid artery intima-media thickness (IMT) predict these events, but few relevant studies have been conducted. We compared long-term changes in arterial stiffness and IMT between patients with REM OSA and non-REM (NREM) OSA receiving continuous positive airway pressure (CPAP) or oral appliance (OA) therapy. METHODS: Newly diagnosed female patients with OSA received CPAP (n = 6) or OA (n = 7). Pulse wave velocity (PWV) and carotid artery ultrasound were performed before and 60 months after treatment. RESULTS: There were no differences in baseline characteristics (mean age: 56.0 vs. 61.3 years; mean body mass index: 22.6 vs. 21.7 kg/m2) between the REM OSA and non-REM OSA groups. The median apnea-hypopnea index was lower in the REM OSA group than in the non-REM OSA group. Increased PWV (12.92 ± 1.64 to 14.56 ± 2.73 m/s) and deteriorated glucose metabolism were observed in the REM OSA group after treatment. PWV, IMT, and cardiovascular risk factors were unaffected in the non-REM OSA group. CONCLUSION: Arterial stiffness and glucose metabolism are deteriorated in patients with REM OSA compared with these parameters in patients with non-REM OSA after CPAP or OA treatment.

Effects of Continuous Positive Airway Pressure Therapy on Nocturnal Blood Pressure Fluctuation Patterns in Patients with Obstructive Sleep Apnea.

This retrospective study was designed to evaluate the effects of continuous positive airway pressure (CPAP) therapy, a well-established treatment for obstructive sleep apnea (OSA), on nocturnal blood pressure fluctuations (NBPFs) during rapid eye movement (REM) and non-REM sleep, and to evaluate the NBPF patterns in patients with OSA. We included 34 patients with moderate-to-severe OSA who underwent polysomnography using pulse transit time before and at 3−6 months after CPAP therapy. Nocturnal BP and NBPF frequency in REM and non-REM sleep were investigated, as well as NBPF pattern changes after receiving CPAP therapy. CPAP therapy resulted in significant reductions in the apnea−hypopnea index (AHI), arousal index, nocturnal systolic and diastolic BP, and NBPF frequency in REM and non-REM sleep (all p < 0.01). A higher AHI before CPAP resulted in lower nocturnal systolic BP (r = 0.40, p = 0.019) and NBPFs (r = 0.51, p = 0.002) after CPAP. However, 58.8% of patients showed no change in NBPF patterns with CPAP therapy. CPAP therapy significantly improved almost all sleep-related parameters, nocturnal BP, and NBPF frequency in REM and non-REM sleep periods, but NBPF patterns showed various changes post-CPAP therapy. These results suggest that factors other than OSA influence changes in NBPF patterns.

Nocturnal hypoxemia is related to morning negative affectivity in untreated patients with severe obstructive sleep apnea.

The relationship between sleep apnea and morning affectivity remains unclear. We aimed to clarify how sleep disturbance in patients with obstructive sleep apnea (OSA) influences their affectivity. The enrolled participants underwent the Positive and Negative Affect Schedule on their beds immediately before and after overnight polysomnography. Thirty patients with OSA were divided into two groups according to the apnea-hypopnea index (AHI): mild to moderate OSA (5 ≤ AHI < 30/h) and severe OSA (AHI ≥ 30/h) groups. Additionally, 11 healthy participants (AHI < 5/h) were included as the control group. No independent association was found between affectivity and OSA severity markers in the whole population; however, the severe OSA group had a significantly higher cumulative percentage of sleep time at saturations < 90% (CT90) and worsened morning negative affectivity. Multiple regression analysis showed that CT90 was an independent factor for increasing negative affectivity in the severe OSA group (p = 0.0422). In patients with OSA, the receiver operating characteristic curve analysis showed that the best cutoff value for CT90 for predicting no decrease in negative affectivity after sleep was 1.0% (sensitivity = 0.56, specificity = 0.86); the corresponding area under the curve was 0.71. Worsening of negative affectivity in the morning was influenced by nocturnal hypoxemia in patients with severe OSA.

Efficacy of a Combination Therapy for Difficulties Waking Up in Non-School-Attending Students.

School non-attendance due to difficulties waking up is increasing in Japan, and affected students are commonly diagnosed with orthostatic dysregulation (OD); however, OD-associated sleep problems are overlooked. To date, no sleep-medicine-based treatment for wake-up difficulties in non-school-attending students has been established. This study aimed to assess the efficacy of a novel combination therapy for these students. We assessed the combined effect of sleep hygiene guidance, low-dose aripiprazole administration (3 mg/day), and blue-light exposure on wake-up difficulty in 21 non-school-attending teenage patients. The patients were evaluated using sleep studies and questionnaires before and after treatment. The average subjective total sleep time calculated from sleep diaries before treatment in the patients was 10.3 h. The therapy improved wake-up difficulty by 85.7% and further improved school non-attendance by 66.7%. The subjective sleep time significantly decreased by 9.5 h after treatment (p = 0.0004). The self-rating Depression Scale and mental component summary of the 36-item Short-Form Health Survey significantly improved after treatment (p = 0.002 and p = 0.01, respectively). Wake-up difficulties were caused by the addition of a delayed sleep phase to the patients' long sleep times. The novel combination therapy was effective in improving wake-up difficulty and mental quality of life in non-school-attending teenage students.

Nocturnal Blood Pressure Fluctuations in Patients with Rapid Eye Movement-Related Obstructive Sleep Apnea.

Rapid eye movement-related obstructive sleep apnea (REM-related OSA) is a polysomnographic phenotype. Nocturnal blood pressure (BP) fluctuations remain unclear in patients with REM-related OSA. We studied 27 patients with REM-related OSA, categorized as having REM-apnea-hypopnea index (REM-AHI) ≥ 5/h, REM-AHI/non-REM-AHI ≥ 2, and non-REM-AHI < 15/h. Beat-to-beat systolic BP (SBP) variability and nocturnal SBP fluctuation patterns using pulse transit time (PTT) were investigated. The maximum increase and average nocturnal SBP were significantly higher in males than in females (p = 0.003 and p = 0.008, respectively). The rate of non-dipping patterns in nocturnal SBP fluctuations was 63% in all patients (males, 70%; females, 50%). Epworth Sleepiness Scale (ESS) and Self-rating Depression Scale (SDS) scores in females were higher than those in males (8.4 ± 6.1 vs. 13.4 ± 5.4 points, p = 0.04; 43.8 ± 7.9 vs. 52 ± 11.6 points, p = 0.04, respectively). A high proportion of patients with REM-related OSA had a non-dipping pattern. Using PPT, we observed that in patients with REM-related OSA, SBP variability was greater in males. Despite clinical symptoms being slightly more severe in females, nocturnal SBP fluctuations should be considered in male patients with REM-related OSA.

[Associated factors for drowsy driving among licensed drivers].

OBJECTIVE: The aim of this study is to reveal factors associated with both dozing off at the wheel and motor vehicle accidents (MVAs) with sleep apnea syndrome (SAS) as well as other descriptive variables for driving set as independent factors. METHODS: We conducted an anonymous questionnaire survey on drivers who visited the Tokyo Metropolitan Driver and Vehicle Licensing Center in order to renew their driver's license from September 25 to 29, 2006. The survey requested information regarding self reported experience of dozing off at the wheel, MVAs, usual mileage, length of license holding period, and the participants' awareness of SAS. We obtained data from 3,236 drivers (response rate: 61.8%). RESULTS: The rates for previous experience of feeling sleepiness at the wheel, that of dozing off at the wheel, and that of near-miss or actual MVA due to dozing off at the wheel among the participants were 40.4%, 20.3%, and 10.4% respectively. Multivariate logistic regression analysis revealed that dozing off at the wheel was significantly associated with male gender, long-term holding of a driver's license (> or = 3, < 10 years: OR = 1.58, 95% CI: 1.04-2.42, > or = 10, < 20 years: OR = 2.23, 95% CI: 1.47-3.38, > or = 20,< 30 years: OR = 1.89, 95% CI: 1.23-2.90 > or = 30 years: OR = 1.85, 95%CI: 1.18-2.89), higher usual mileage (> or = 30 km per a week: OR = 1.35, 95% CI: 1.06-1.73), appearance of sleepiness shortly after starting driving (< 2 hrs: OR = 1.99, 95% CI: 1.60-2.47), either having awareness or a diagnosis of SAS. As to experience of near-miss or actual MVA due to dozing off at the wheel, factors including male gender, long-term holding period of driver's license (> or = 3, < 10 years: OR = 2.02, 95% CI: 1.15-3.55, > or = 10, < 20 years: OR = 2.10, 95% CI: 1.19-3.70), appearance of sleepiness shortly after starting driving (< 2 hrs: OR = 1.70, 95% CI: 1.30-2.24), either having awareness or diagnosis of SAS were significantly associated. CONCLUSION: Not only habituation effects and fatigue due to long driving but also SAS have a significant impact on the occurrence of sleepiness related MVAs. Moreover, early diagnosis and treatment of SAS is necessary so that we can avoid dozing off at the wheel, resulting in near-miss or actual MVA.

Insomnia as a Symptom of Rapid Eye Movement-Related Obstructive Sleep Apnea.

Rapid eye movement (REM)-related obstructive sleep apnea (OSA), a polysomnographic phenotype that affects 12-36% of OSA patients, is defined by apnea and hypopnea events that predominantly or exclusively occur during REM sleep. Recent studies indicated that REM-related OSA was associated with the development of nocturnal non-dipping of systolic and diastolic blood pressure, metabolic syndrome, diabetes, and depressive symptoms. However, to date, the association between REM-related OSA and insomnia still remains unclear. We investigated whether there was a difference between REM- and non-REM-related OSA in terms of insomnia-related sleep disturbance as measured by the Pittsburgh Sleep Quality Index (PSQI) in 1736 patients with OSA. REM-related OSA showed a significant association with increased PSQI in all adjusted models. In the subgroup analysis, the coefficients of all models were higher in female than in male patients with REM-related OSA. Insomnia should be considered an important complaint in patients with REM-related OSA, and its indicators, such as the PSQI, should be included in routine diagnostic testing.