How to cite this article:
Vasudev P, Arjun P, Azeez AK, Nair S. Prevalence of Cognitive Impairment in Obstructive Sleep Apnea and Its Association with the Severity of Obstructive Sleep Apnea: A Cross-sectional Study. Indian Sleep Med 2020; 15 (4):55-59.
Background: Cognitive impairment in obstructive sleep apnea (OSA) is a widely unrecognized entity. Earlier studies have shown variable results for the prevalence of this entity. Hence, this study was done to determine the prevalence of cognitive impairment in patients diagnosed to have OSA and its association with the severity of OSA.
Materials and methods: All in-patients and outpatients who were diagnosed to have OSA by polysomnography in a tertiary care hospital in Kerala, India, were included in this study. Cognitive function was assessed by Montreal cognitive assessment (MoCA) and their scores were calculated. Daytime sleepiness was assessed by the Epworth sleepiness scale (ESS).
Results: 96 OSA patients were included in the study. 19.8% of patients had mild OSA, 29.2% of patients had moderate OSA, and 51% of patients had severe OSA. The prevalence of cognitive impairment in OSA patients in this study was found to be 58.3% (95% confidence interval, 47.8–68.3%). There were 35 (62.5%) patients with cognitive impairment in the severe OSA group, while the moderate and mild OSA groups had 17 (30.4%) and 4 (7.1%) patients, respectively. There was a significant negative correlation between AHI and MoCA score, indicating that cognitive impairment is associated with the severity of OSA.
Conclusion: The prevalence of cognitive impairment in our study was 58.3%, which was found to be more in those with severe OSA. It was also found that cognitive impairment is associated with the severity of OSA.
Clinical implications: Cognitive impairment in OSA is associated with the severity of OSA and is a correctable condition that can improve the quality of life.
Context: The study was done to assess the impact of obstructive sleep apnea (OSA) on acute ischemic stroke.
Aims and objectives: To see the prevalence and severity of obstructive sleep apnea in patients with acute ischemic stroke in Rajasthan, to identify patients with acute ischemic stroke who should be screened for OSA, and to compare short-term neurological and functional outcomes in stroke patients with and without OSA.
Settings and design: This is a prospective analytical study of 50 patients with acute ischemic stroke.
Materials and methods: National Institute of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) scores were calculated at admission. After 10 days, all patients underwent minimum 4 hours of polysomnography. OSA was diagnosed when apneas hypopneas index (AHI) is more than 5 per hour. NIHSS scoring was done at discharge, and mRS scoring was done after 1 month.
Statistical analysis used: Categorical variables were compared using the χ2 test and numerical variables using the t-test for independent samples. Statistical significance was set at 5%.
Results: The prevalence of OSA was 36%. Obesity and high Epworth sleepiness scale were predictors of OSA. The distribution of stroke topography was similar in OSA and non-OSA groups. NIHSS and mRS were comparable in OSA and non-OSA groups. Difference in recovery of NIHSS was significant between OSA and non-OSA groups (1.16 and 2, respectively, p-value: 0.0017). There was a statistically significant difference in mRS at 1 month between OSA and non-OSA groups (2.88 and 2.53, respectively, p-value: 0.02).
Conclusions: As poor neurological recovery during the hospital stay and poor functional recovery at 1 month in patients with acute ischemic stroke with OSA were found, our study highlights screening of OSA particularly for obese patients and patients with high Epworth sleepiness scale.
Aim and objective: There are insufficient data in India on sleep issues in children with Prader–Willi syndrome (PWS). This study was undertaken to describe the prevalence of sleep problems, polysomnography findings, and treatment of sleep issues in children with PWS.
Research questions: (1) To determine the prevalence of sleep problems in children with PWS and (2) to compare the polysomnography (PSG) findings in children with PWS and non-syndromic children with obstructive sleep apnea (OSA).
Materials and methods: Retrospective data of children who underwent polysomnography for the diagnosis of sleep problems were extracted and divided into two groups. The first group consisted of 20 children with PWS, and the second group consisted of 22 non-syndromic children with OSA. History was analyzed using a parent-administered sleep questionnaire, and a level one polysomnography was performed in all study subjects.
Results: No significant difference was noted in the sleep history between the two groups. The OSA prevalence of the PWS group was 100%. The OAHI, OAHI (REM), baseline oxygen saturation, and time of saturation below 90% were significantly affected in the PWS group compared to the non-syndromic group. Thirteen children with PWS who had moderate-to-severe OSA were started on CPAP and were clinically better, of which nine of them who underwent a follow-up sleep study showed resolution of OSA on PSG.
Conclusion: Children with PWS suffer from moderate-to-severe OSA. OSA with significant hypoxemia is seen in REM sleep in PWS children, necessitating the need for early intervention with noninvasive ventilation. All children with PWS must undergo PSG due to possible underestimation of sleep issues on parental history.
Clinical significance: The degree of obstruction could be underestimated on parental history in children with PWS, thus necessitating the need for a sleep study in all children with PWS, especially prior to hGH therapy.
Mary I Charles,
Aim and objective: Obstructive sleep apnea (OSA) is a common yet underdiagnosed sleep disorder associated with partial or complete obstruction of upper airway during sleep. Floppy eyelid syndrome (FES) is another frequently overlooked diagnosis associated with lax upper eyelids, a soft and foldable tarsus, and a chronic papillary conjunctivitis of the upper palpebral conjunctiva. There has been growing literature to support the association between the two, and this study explores the same and also the clinical implications.
Materials and methods: Retrospective study from 2015 to 2018 at a freestanding sleep clinic, India. Patients who were diagnosed with FES at an ophthalmic care hospital, and referred for evaluation of suspected OSA based on symptoms of snoring and daytime hypersomnolence were included in the study. Subjects underwent clinical evaluation and polysomnography, if required.
Results: All the referrals were males and the mean age was 49.8 ± 13.4. Of 51 patients, 13 (25.4%) were not willing to undergo sleep study as they were unwilling to accept the possible association of OSA and FES and/or could not afford additional testing. Thirty-six of the 38 patients with FES were diagnosed of OSA (94.8%) and 20 of 38 had severe OSA (55.5%). Of the 38 patients diagnosed with OSA, only one patient accepted continuous positive airway pressure (CPAP) therapy.
Conclusions: Ophthalmologists were able to effectively screen patients for OSA with simple screening questions about snoring and daytime hypersomnolence. The association between OSA and FES was significant but a large proportion of patients were not ready to undergo sleep study or commence treatment despite being diagnosed and explained the consequences of untreated severe OSA.