Olga Berdina

Abstract: Obstructive sleep apnea (OSA) is a very serious and multifactorial sleep disorder in relation to the risk of developing cognitive impairment. There are main pathogenetic mechanisms of OSA such as remittent nocturnal hypoxemia and altered sleep homeostasis, which through a cascade of pathophysiological reactions (endothelial dysfunction, oxidative stress, neuroinflammation, cerebral hypoperfusion et al.) could initiate disruptions in cellular and biochemical homeostasis to metabolic and morphofunctional changes in the brain. It is known that childhood obesity aggravates cognitive impairment in OSA. Based on the above relationships, the study aimed to evaluate the cognitive performance and their potential associations with polysomnographic (PSG) variables in OSA adolescent samples aged 15-17 years with different weight status. One-night in-lab PSG was carried out to estimate sleep data. The Wechsler Intelligence Scale for Children fourth edition (WISC-IV, Russian Version) was applied to evaluate the participants’ cognition. Full-scall cognitive ability quotient (FSCAQ), visual-spatial index, fluid reasoning index, working memory index, and processing speed index (PSI) scores were significantly lower for obese OSA adolescents. Nonobese OSA participants had significantly lower FSCAQ and PSI scores compared with those in controls without OSA but were similar who was obese by all WISC-IV indexes. Multiple linear regression analysis revealed that k-complexes (KK) density, «sleep spindles» (SSs) duration and wake after sleep onset for nonobese adolescents, as well as apnea-hypopnea index, oxygen desaturation index, number of awaking, KKs and SSs densities, and sleep fragmentation index for obese peers were negative associated with cognitive functions. In conclusion, the cognitive performance in pediatric OSA is decreasing with a predominant deterioration of non-verbal abilities, due to alteration of sleep homeostasis in OSA without obesity, and the potentiated effect of hypoxia severity and sleep fragmentation in obesity.

Speaker: Olga Berdina is PhD, Leading researcher of Laboratory of Somnology and Neurophysiology of Scientific Centre for Family Health and Human Reproduction Problems, Pediatrician and Functional Diagnostics Specialist of Innovation Center of Scientific Centre for Family Health and Human Reproduction Problems. She has been conducting research in the field of fundamental and applied aspects of sleep disorders and associated conditions in pediatrics, developing innovative technologies for their early diagnosis, prevention and prognosis. She has owned more than 100 peer-review papers in Sleep Medicine, Journal of Sleep Research, Sleep and Biological Rhythms, Frontiers in Pediatrics, The European Physical Journal, Canadian Respiratory Journal, Archives of Disease in Childhood et al., and 100 sectionally or invited talk on international conferences, including Forum BRICS, ECOG, Europaediatrics, Congress of the Asian College of Psychosomatic Medicine IPA Congress & PEDICON et al.