Prevalence, Incidence, and Progression of Cognitive Impairment, No Dementia Among Rural-Dwelling Chinese Older Adults

Article type: Research Article

Authors: Ren, Yifei^a | Dong, Yi^a | Hou, Tingting^{a; b; c} | Han, Xiaolei^a | Liu, Rui^a | Wang, Yongxiang^{a; b; c} | Xu, Shan^a | Wang, Xiang^{a; b; c} | Monastero, Roberto^d | Cong, Lin^{a; b; c; *} | Du, Yifeng^{a; b; c; *} | Qiu, Chengxuan^{a; e}

Affiliations: [a] Department of Neurology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, P. R. China | [b] Department of Neurology, Shandong Provincial Hospital affiliated to Shandong First Medical University, Jinan, Shandong, P. R. China | [c] Shandong Provincial Clinical Research Center for Geriatric Neurological Diseases, Jinan, Shandong, P. R. China | [d] Department of Biomedicine, Neuroscience and Advanced Diagnostics, University of Palermo, Palermo, Italy | [e] Aging Research Center and Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet-Stockholm University, Stockholm, Sweden

Correspondence: [*] Correspondence to: Prof. Yifeng Du, Department of Neurology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, No. 324 Jingwuweiqi Road, Jinan, Shandong 250021, P. R. China. E-mail: duyifeng2013@163.com or Dr. Lin Cong, conglin667@163.com.

Abstract: Background:Few studies have examined occurrence and progression of cognitive impairment, no dementia (CIND) in rural China. Objective:To determine the prevalence and incidence of CIND in rural-dwelling Chinese older adults, and to examine risk and protective factors associated with progression to CIND and dementia. Methods:This population-based study included 2,781 dementia-free participants (age≥65 years) who were examined at baseline (2014) and followed in 2018. Demographic, epidemiological, clinical, and neuropsychological data were collected following a structured questionnaire. We defined CIND according to subjective cognitive complaints and the age- and education-specific Mini-Mental State Examination (MMSE) score. Data were analyzed with the multinomial logistic regression models. Results:The overall prevalence of CIND was 10.54% and the incidence was 28.26 per 1,000 person-years. CIND at baseline was associated with the multi-adjusted odds ratio (OR) of 2.06 (95% confidence interval = 1.23–3.47) for incident dementia. Multinomial logistic regression analysis suggested that compared with no CIND, the multi-adjusted OR of incident CIND was 2.21 (1.51–3.23) for women and 0.62 (0.38–0.99) for high social support, whereas the multi-adjusted OR of incident dementia was 1.14 (1.09–1.18) for older age, 0.29 (0.16–0.53) for high education, and 2.91 (1.47–5.74) for having a stroke history. Conclusion:CIND affects over one-tenth of older adults living in rural communities of western Shandong province. People with CIND are twice as likely to progress to dementia as people without CIND. Female sex, low education, stroke history, and low social support are associated with an increased risk of progression from normal cognition to CIND or dementia.

Keywords: Cognitive impairments, incidence, population-based study, prevalence, risk factors, rural

DOI: 10.3233/JAD-215236

Journal: Journal of Alzheimer's Disease, vol. 85, no. 4, pp. 1583-1592, 2022