Sex Differences in the Prevalence of and Risk Factors for Cognitive Impairment No Dementia among the Elderly in a Rural Area of Northern China: A Population-Based Cross-Sectional Study

2021

ADR

Background: It is inconclusive on how sex affects the risk of developing mild cognitive impairment (MCI) or dementia. Objective: To investigate how sex affects the risk of developing MCI or dementia. Methods: A secondary data analysis was performed on data collected from participants enrolled at Alzheimer’s Disease Research Centers funded by National Institute on Aging. There were two inclusion criteria: 1) participants were free of dementia at the baseline visit; 2) every participant must have at least one follow-up visit. A Cox proportional hazards model was used to investigate how sex affects the risk of developing cognitive impairments. Results: During a follow-up period of more than 10 years, male participants had a slightly higher incidence than female participants for either MCI or dementia. Not surprisingly, a higher prevalence was observed in male than female participants for either MCI or dementia. However, male participants had a higher mortality rate than their female counterparts. Conclusion: The male sex is associated with a higher risk for developing cognitive impairments along the aging process.

Section: Discussionsupporting

confidence: 93%

Sex as a Risk Factor for Developing Cognitive Impairments in National Alzheimer’s Coordinating Center Participants

2021

ADR

“…Before the age of 75 years old, the prevalence rate is similar between female and males, while a significant higher prevalence was found after age 75 years in women. Gender differences in cognitive impairment are inconclusive in previous studies, with more studies reporting higher prevalence in females [9,23]. Some studies report a higher prevalence of vascular dementia in men, while females have more Alzheimer's disease than men [9,10].However, gender differences in the prevalence of vascular dementia reverse with advancing age, with a higher prevalence among women after age 80 [16,24].…”

Section: Discussionmentioning

confidence: 99%

Gender Differences in Cognitive Impairment among Rural Elderly in China

Xiao

et al. 2020

IJERPH

Elders in rural areas of developing countries are particularly vulnerable to cognitive impairment and gender disparities are notable. Yet, evidence related to gender differences in cognitive impairment in these settings is scarce. This study examined gender differences in cognitive impairment among elderly people aged 65 and above in rural China. A multi-site cross-sectional survey was conducted. In total, 550 males and 700 females were recruited. The Chinese version of the Mini-Mental Status Examination was applied for cognitive impairment screening. Demographic information, lifestyle factors, psychosocial factors, and health-related information were assessed. The prevalence of cognitive impairment was 40.0%in males and 45.1% in females, respectively. Females showed significant higher prevalence after age 75 (62.7% vs. 45.4%, p < 0.005). Older age, hearing impairment, and activities of daily living dependence were common factors associated with cognitive impairment in both females and males. For males, living in a neighborhood with poor social interactions and diabetes were risk factors, while tea consumption was a protective factor. For females, vision impairment and illiteracy were additional risk factors. Individualized interventions and standardized measurements of cognitive function should be developed to suit older populations living in rural and less-developed areas, through collective efforts involving all stakeholders and multidisciplinary teamwork.

“…Risk factors for prevalent MCI were investigated in 64/78 studies [20-24, 26-45, 47, 48, 51-60, 62, 67-69, 72-76, 78-87, 89-93, 95, 96]. Two studies [53,67] did not report risk factor information in the original article, however, risk factor data for the same cohort were later published in a separate article [107,108]. In this scenario, we have added the risk factor information as documented in the most recent publication.…”

Section: Associated Risk Factorsmentioning

confidence: 99%

Prevalence and Risk of Mild Cognitive Impairment in Low and Middle-Income Countries: A Systematic Review

McGrattan

Zhu

Richardson

et al. 2021

JAD

Background: Mild cognitive impairment (MCI) is a cognitive state associated with increased risk of dementia. Little research on MCI exists from low-and middle-income countries (LMICs), despite high prevalence of dementia in these settings. Objective: This systematic review aimed to review epidemiological reports to determine the prevalence of MCI and its associated risk factors in LMICs. Methods: Medline, Embase, and PsycINFO were searched from inception until November 2019. Eligible articles reported on MCI in population or community-based studies from LMICs and were included as long as MCI was clearly defined. Results: 5,568 articles were screened, and 78 retained. In total, n = 23 different LMICs were represented; mostly from China (n = 55 studies). Few studies were from countries defined as lower-middle income (n = 14), low income (n = 4), or from population representative samples (n = 4). There was large heterogeneity in how MCI was diagnosed; with Petersen criteria the most commonly applied (n = 26). Prevalence of amnesic MCI (aMCI) (Petersen criteria) ranged from 0.6%to 22.3%. Similar variability existed across studies using the International Working Group Criteria for aMCI (range 4.5%to 18.3%) and all-MCI (range 6.1%to 30.4%). Risk of MCI was associated with demographic (e.g., age), health (e.g., cardio-metabolic disease), and lifestyle (e.g., social isolation, smoking, diet and physical activity) factors. Conclusion: Outside of China, few MCI studies have been conducted in LMIC settings. There is an urgent need for population representative epidemiological studies to determine MCI prevalence in LMICs. MCI diagnostic methodology also needs to be standardized. This will allow for cross-study comparison and future resource planning.