The issue of air pollution is gaining increasing attention worldwide, and mounting evidence has shown an association between air pollution and cognitive decline. The aim of this study was to investigate the relationships between air pollutants and cognitive impairment using the Mini-Mental State Exam (MMSE) and its sub-domains. In this study, we used data from the Taiwan Biobank combined with detailed daily data on air pollution. Cognitive function was assessed using the MMSE and its five subgroups of cognitive functioning. After multivariable linear regression analysis, a high level of particulate matter with an aerodynamic diameter of ≤2.5 μm (PM_2.5), low ozone (O₃), high carbon monoxide (CO), high sulfur dioxide (SO₂), high nitric oxide (NO), high nitrogen dioxide (NO₂), and high nitrogen oxide (NO_x) were significantly associated with low total MMSE scores. Further, high SO₂ and low O₃ were significantly associated with low MMSE G1 scores. Low O₃, high CO, high SO₂, high NO₂, and high NO_x were significantly associated with low MMSE G4 scores, and high PM_2.5, high particulate matter with an aerodynamic diameter of ≤10 μm (PM₁₀), high SO₂, high NO₂, and high NO_x were significantly associated with low MMSE G5 scores. Our results showed that exposure to different air pollutants may lead to general cognitive decline and impairment of specific domains of cognitive functioning, and O₃ may be a protective factor. These findings may be helpful in the development of policies regarding the regulation of air pollution.

Perceived sleep quality may play an important role in diagnosis and therapy for obstructive sleep apnea (OSA). However, few studies have assessed factors that are associated with perceived sleep quality in OSA patients. Hypoxemia depresses the central nervous system and attenuates the perceived respiratory load in asthmatic patients. This study aimed to investigate the factors related to perceived sleep quality, focusing on the role of hypoxemia. Polysomnography studies of 156 OSA patients were reviewed. Traditional polysomnographic parameters, including parameters of oxy-hemoglobin saturation (SpO2), were calculated, and the sleep questionnaire and scales were used. Considering the possible pitfalls of absolute values of SpO2 and individualized responses to hypoxemia, the amplitude of desaturation was further computed as “median SpO2 minus lowest 5 % SpO2 “and “highest 5 % SpO2 minus median 5 % SpO2”. Correlations between these parameters and perceived sleep quality, represented as the Pittsburgh sleep quality index (PSQI), were performed. Multiple linear regression analysis was also conducted to investigate the factors associated with the PSQI. Although the PSQI was not correlated with the apnea-hypopnea index (r = −0.113, p = 0.162) and oxygen desaturation index (r = −0.085, p = 0.291), the PSQI was negatively correlated with “median SpO2 minus lowest 5 % SpO2” (r = −0.161, p = 0.045). After adjusting for age, total sleep time, the periodic limb movements index, tendency of depression, and the lowest 5 % SpO2, the “median SpO2 minus lowest SpO2” was still a significant predictor for a lower PSQI (β = −0.357, p = 0.015). More severe hypoxemia is associated with better perceived sleep quality among OSA patients. This paradox may be associated with hypoxemia-related impairment of perception. The effect of hypoxemia did not appear to be significant in relatively mild hypoxemia but become significant in severe hypoxemia.” Median SpO2 minus lowest 5 % SpO2” may also be a better predictor of perceived sleep quality than the apnea-hypopnea index because of the disproportionate effects of hypoxemia. Additionally, further studies are necessary to confirm the role of hypoxemia on perceived sleep quality and identify the possible threshold of hypoxemia in OSA patients.

Objectives: Behavioral and psychological symptoms of dementia (BPSD) are frequently met in Alzheimer’s disease (AD), especially in their late stages. BPSD has been reported to be associated with gender for its biological characteristics and severity of dementia. We aimed to investigate the gender differences in presentation of BPSD in AD in Taiwan. Methods: We recruited patients with clinically diagnosed AD by National Institute of Neurological Disorders and Stroke (NINCDS) - Alzheimer’s Disease and Related Disorders Association (ADRDA) criteria. Demographic data and annual psychometrics, including Mini-Mental State Examination (MMSE), Clinical Dementia Rating (CDR) and Neuropsychiatric Inventory (NPI), consisting sub-items of delusions, hallucinations, aggression, depression, anxiety, elation, apathy, disinhibition, irritability, aberrant motor, nighttime behavior and eating were all administered to evaluate BPSD. Apolipoprotein E (APOE) allele was genotyped for each recruited AD subject. Differences between gender and variables were compared and significant NPI sub-items associated with gender were determined, while linear regression analyses were determined as the independent factor for BPSD. Results: In total, 280 female and 180 male AD patients were recruited into statistical analyses. Males had longer education duration and higher MMSE scores than females. Female had higher presence of delusion and disinhibition. In linear regression, being female and CDR stage were two independent factors for delusion (for female, B = 0.95, 95% CI = 0.17–1.73, p = 0.017) and disinhibition (for female, B = 0.49, 95% CI = 0.08–0.90, p = 0.019) after adjusting for confounding factors. Conclusions: The presentation of delusion and disinhibition in BPSD is associated with the female gender and staging of AD. Disinhibition was not necessarily associated with late stage of AD.