Associação entre exposição ao material particulado inalável, qualidade do sono e desempenho cognitivo em adultos

Abstract

Introduction: During human development, changes related to sleep patterns and architecture fundamentally affect the expansion and improvement of cognitive and behavioral processes, with cortical maturation as a backdrop. Interestingly, studies indicate a relationship between air pollution and sleep quality when individuals are exposed to high concentrations of air pollutants. Among pollutants, airborne nanoparticles can reach the cortical regions, basal ganglia, and cerebellum through the olfactory nerve after inhalation. Thus, chronic exposure to high concentrations of pollutants can trigger inflammatory processes and alter the levels of neurotransmitters that regulate sleep cycles, which can consequently impair sleep quality, leading to a potential impact on cognition. Objectives: This study sought to analyze the relationship between chronic exposure to inhalable particulate matter and cognitive performance among adults, to the detriment of sleep quality. Methods: Fifty-six volunteers of both sexes, aged between 18 and 35 years, living in Baixada Santista, participated in the study. Exposure to MP₁₀ was estimated based on the average daily levels recorded in the 14 days preceding the neuropsychological evaluation, according to data from CETESB. In addition to self-report inventories, sleep patterns were measured by home polysomnography with a portable sensor (Biologix®). To assess cognitive and affective functions, standardized neuropsychological instruments were used for general intelligence (Wechsler Abbreviated Intelligence Scale), verbal episodic memory (Rey Auditory-Verbal Learning Test), visual episodic memory (Rey Complex Figures), cognitive flexibility (Wisconsin Card Sorting Test), self-reported executive functions (Barkley Executive Dysfunction Rating Scale), depressive symptoms (Beck Depression Inventory) and impulsivity (Barratt Impulsivity Scale). Results: The mean exposure to MP₁₀ was 33±1μg/m³, indicating high chronic exposure. Regarding sleep, the mean sleep efficiency was 82±1%, peripheral oxygen saturation was 9±1% and desaturation index was 2.9±1.9 events/hour. Regarding cognitive performance, participants presented scores within normal limits in the main domains evaluated, such as general intelligence (108±1), verbal episodic memory (68±3), visual episodic memory (0.3±0.1), and cognitive flexibility, represented by the number of perseverative errors (10±1). Regarding self-reported executive functions, the factors of organization and problem-solving (47±2), emotional regulation (26±1), and time management (42±2) stand out. Finally, regarding affective and behavioral aspects, participants presented mild levels of depressive symptoms (11±8) and controlled global impulsivity (66±1). We observed a significant inverse correlation between chronic exposure to MP₁₀ and the forgetting speed index (ρ= -0.30; P= 0.02), as well as a trend towards a positive correlation with inattentional impulsivity (ρ= 0.23; P= 0.10). The other variables did not show significant associations, including peripheral oxygen saturation and cognitive domains. Conclusion: The data suggest that chronic exposure to MP₁₀ may selectively affect the consolidation of verbal episodic memory and attentional aspects, highlighting the importance of investigating the neurocognitive effects of air pollution in adult populations.