Association Between Long-Term Exposure to Ambient Air Pollution and the Risk of Mild Cognitive Impairment in a Chinese Urban Area: A Case-Control Study

Background

As a prodromal stage of dementia, significant emphasis has been placed on the identification of modifiable risks of mild cognitive impairment (MCI). Research has indicated a correlation between exposure to air pollution and cognitive function in older adults. However, few studies have examined such an association among the MCI population inChina.

Objective

We aimed to explore the association between air pollution exposure and MCI risk from the Hubei Memory and Aging Cohort Study.

Methods

We measured four pollutants from 2015 to 2018, 3 years before the cognitive assessment of the participants. Logistic regression models were employed to calculate odds ratios (ORs) to assess the relationship between air pollutants and MCI risk.

Results

Among 4,205 older participants, the adjusted ORs of MCI risk for the highest quartile of PM2.5, PM10, O3, and SO2 were 1.90 (1.39, 2.62), 1.77 (1.28, 2.47), 0.56 (0.42, 0.75), and 1.18 (0.87, 1.61) respectively, compared with the lowest quartile. Stratified analyses indicated that such associations were found in both males and females, but were more significant in older participants.

Conclusions

Our findings are consistent with the growing evidence suggesting that air pollution increases the risk of mild cognitive decline, which has considerable guiding significance for early intervention of dementia in the older population. Further studies in other populations and broader geographical areas are warranted to validate these findings.

Prevalence and risk factors for subjective cognitive decline and the correlation with objective cognition among community-dwelling older adults in China: Results from the Hubei memory and aging cohort study

INTRODUCTION

The prevalence and risk factors for subjective cognitive decline (SCD) and its correlation with objective cognition decline (OCD) among community-dwelling older adults is inconsistent.

METHODS

Older adults underwent neuropsychological and clinical evaluations to reach a consensus on diagnoses.

RESULTS

This study included 7486 adults without mild cognitive impairment and dementia (mean age: 71.35 years [standard deviation = 5.40]). The sex-, age-, and residence-adjusted SCD prevalence was 58.33% overall (95% confidence interval: 58.29% to 58.37%), with higher rates of 61.25% and 59.87% in rural and female subgroups, respectively. SCD global and OCD language, SCD memory and OCD global, SCD and OCD memory, and SCD and OCD language were negatively correlated in fully adjusted models. Seven health and lifestyle factors were associated with an increased risk for SCD.

DISCUSSION

SCD affected 58.33% of older adults and may indicate concurrent OCD, which should prompt the initiation of preventative intervention for dementia.

HIGHLIGHTS

SCD affects 58.33% of older adults in China. SCD may indicate concurrent objective cognitive decline. Difficulty finding words and memory impairments may indicate a risk for AD. The presence of SCD may prompt preventative treatment initiation of MCI or dementia. Social network factors may be initial targets for the early prevention of SCD.

Population-attributable fractions of risk factors for all-cause dementia in China rural and urban areas: a cross-sectional study

BACKGROUND

The prevalence of dementia in China, particularly in rural areas, is consistently increasing; however, research on population-attributable fractions (PAFs) of risk factors for dementia is scarce.

METHODS

We conducted a cross-sectional survey, namely, the China Multicentre Dementia Survey (CMDS) in selected rural and urban areas from 2018 to 2020. We performed face-to-face interviews and neuropsychological and clinical assessments to reach a consensus on dementia diagnosis. Prevalence and weighted PAFs of eight modifiable risk factors (six classical: less childhood education, hearing impairment, depression, physical inactivity, diabetes, and social isolation, and two novels: olfactory decline and being unmarried) for all-cause dementia were estimated.

RESULTS

Overall, CMDS included 17,589 respondents aged ≥ 65 years, 55.6% of whom were rural residents. The age- and sex-adjusted prevalence for all-cause dementia was 9.11% (95% CI 8.96-9.26), 5.19% (5.07-5.31), and 11.98% (11.8-12.15) in the whole, urban, and rural areas of China, respectively. Further, the overall weighted PAFs of the eight potentially modifiable risk factors were 53.72% (95% CI 52.73-54.71), 50.64% (49.4-51.89), and 56.54% (55.62-57.46) in the whole, urban, and rural areas of China, respectively. The eight risk factors' prevalence differed between rural and urban areas. Lower childhood education (PAF: 13.92%) and physical inactivity (16.99%) were primary risk factors in rural and urban areas, respectively.

CONCLUSIONS

The substantial urban-rural disparities in the prevalence of dementia and its risk factors exist, suggesting the requirement of resident-specific dementia-prevention strategies.

The Hubei Memory and Aging Cohort Study: Study Design, Baseline Characteristics, and Prevalence of Cognitive Impairments

BACKGROUND

Despite the improved access to health services in China, inadequate diagnosis and management of dementia are common issues, especially in rural regions.

OBJECTIVE

The Hubei Memory & Aging Cohort Study was designed as a prospective study in Central China to determine the prevalence, incidence, and risk factors for dementia and mild cognitive impairment (MCI) among urban and rural older adults.

METHODS

From 2018-2020, participants aged ≥65 years were screened, and data regarding their life behaviors, families, socio-economic status, physical and mental health, social and psychological factors, and cognition were collected. Diagnoses of MCI and dementia were made via consensus diagnosis using the Diagnostic and Statistical Manual of Mental Disorders fourth edition criteria.

RESULTS

Of 8,221 individuals who completed their baseline clinical evaluation, 4,449 (54.1%) were women and 3,164 (38.4%) were from remote rural areas (average age: 71.96 years; mean education period: 7.58 years). At baseline, 25.98%(95%confidence interval [CI]: 24.99-26.96) and 7.24%(95%CI: 6.68-7.80) of the participants were diagnosed with MCI and dementia, respectively. Prevalence showed a strong relationship with age. The substantial disparities between rural and urban regions in MCI and dementia prevalence and multiple dementia-related risk factors were revealed. Especially for dementia, the prevalence rate in rural areas was 2.65 times higher than that in urban regions.

CONCLUSION

Our results suggested that public health interventions are urgently needed to achieve equitable diagnosis and management for people living with dementia in the communities across urban and rural areas.

Extracapsular dissection versus partial superficial parotidectomy for the treatment of benign parotid tumours

The purpose of this study was to compare the complications of patients treated for a benign parotid tumour (BPT) by extracapsular dissection (ECD) vs. partial superficial parotidectomy (PSP). A comprehensive literature investigation was conducted by searching electronic databases. A systematic review and meta-analysis of comparative studies were performed to assess ECD and PSP for the treatment of BPTs with fixed-effects models. The outcomes analysed were transient or permanent facial nerve injury, Frey syndrome, recurrence rate, infection, and salivary fistula/sialocele. A total of 1641 patients from seven studies (1120 ECD-treated and 521 PSP-treated patients) were included in this meta-analysis. Transient facial nerve injury (odds ratio (OR)=0.28, 95% confidence interval (CI): 0.11-0.71; p=0.008) and Frey syndrome (OR=0.12, 95% CI: 0.03-0.48; p=0.003) were less prevalent in the ECD group. The rates of permanent facial nerve injury (OR=0.77, 95% CI: 0.35-1.70; p=0.520), recurrence rate (OR=0.17, 95% CI: 0.02-1.75; p=0.14), infection (OR=0.70, 95% CI: 0.07-6.67; p=0.76), and salivary fistula/sialocele (OR=0.40, 95% CI: 0.06-2.66; p=0.350) were similar in both groups. Although there was a trend that ECD showed a reduced risk for complications, the present results are not sufficient to conclude that ECD is more beneficial than PSP.

Knockdown of Radixin Suppresses Gastric Cancer Metastasis In Vitro by Up-Regulation of E-Cadherin via NF-κB/Snail Pathway

Background/Aims: Radixin has recently been shown to correlate with the metastasis of gastric cancer, but the pathogenesis is elusive. Adhesion proteins contribute to the regulation of metastasis, and thus this study sought to investigate the role of radixin in the migration, invasion and adhesion of gastric cancer cells, as well as its interaction with adhesion proteins in vitro. Methods: Radixin stable knockdown human gastric carcinoma SGC-7901 cells were constructed. Alterations in the migration, invasion and adhesion ability were examined by matrigel-coated plate and transwell assays. The expression pattern of adhesion proteins, including E-cadherin, β-catenin and claudin-1, was determined by quantitative real-time PCR and western blot. Possible involvement of NF-κB/snail pathway was also evaluated. Results: Stable knockdown of radixin significantly suppressed migration and invasion, but enhanced adhesion in SGC-7901 cells. The expression of E-cadherin was manifestly increased in radixin knockdown cells, whereas the expression of β-catenin and claudin-1 was unchanged. The nuclear exclusion of NF-κB followed by conspicuous reduction of snail expression was involved in the regulation of E-cadherin expression. Conclusions: Radixin knockdown suppresses the metastasis of SGC-7901 cells in vitro by up-regulation of E-cadherin. The NF-κB/snail pathway contributes to the regulation of E-cadherin in response to depletion of radixin.