Association of Occupational Factors and Dementia or Cognitive Impairment: A Systematic Review and Meta-Analysis

Article type: Research Article

Authors: Huang, Liang-Yu^a | Hu, He-Ying^a | Wang, Zuo-Teng^a | Ma, Ya-Hui^a | Dong, Qiang^b | Tan, Lan^{a; *} | Yu, Jin-Tai^{b; *}

Affiliations: [a] Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China | [b] Department of Neurology and Institute of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China

Correspondence: [*] Correspondence to: Dr. Jin-Tai Yu, MD, PhD, Department of Neurology, Huashan Hospital, Fudan University, No. 12 Wulumuqi Road, Shanghai, China. Tel.: +86 21 52888160; Fax: +86 21 62483421; [email protected] and Dr. Lan Tan, MD, PhD, Department of Neurology, Qingdao Municipal Hospital, Qingdao University, No.5 Donghai Middle Road, Qingdao, China. [email protected]

Abstract: Background:Several existing studies have reported that occupational factors might play an important part in cognitive function with aging. Objective:We aim to explore the associations between modifiable occupational factors and risk of dementia or mild cognitive impairment (MCI). Methods:Adopting random-effect models, this study conducted primary analyses for all occupational factors and subgroup analyses for the effect of occupation type based on prospective cohort and case-control studies searched from PubMed and EMBASE databases up to March 2020. Results:Among the 38,111 identified literatures, 9 studies on occupation type, 4 studies on work complexity, and 30 studies on occupational exposure were included. In terms of occupation type, mental work conferred a 44% reduced risk (95% CI = 0.34–0.94, I² = 85.00%, p < 0.01) for MCI. In terms of work complexity, higher work complexity conferred a 5% reduced risk (95% CI = 0.91–1.00, I² = 57.00%, p < 0.01) for dementia. In terms of occupational exposure, high strain and passive job in the longest-held job conferred a 1.21- and 1.15-fold excess risk (95% CI = 1.05–1.39 I² = 62.00%, p < 0.05; 95% CI = 1.05–1.26 I² = 31.00%, p = 0.23; respectively) of cognitive decline. Besides, magnetic field exposure conferred a 1.26-fold excess risk (95% CI = 1.01–1.57, I² = 69.00%, p < 0.01) for dementia. Conclusion:Novel prevention strategies based on occupational factors may hold promise against dementia and MCI.

Keywords: Dementia, job strain, meta-analysis, occupation, occupational exposure, work complexity

DOI: 10.3233/JAD-200605

Journal: Journal of Alzheimer's Disease, vol. 78, no. 1, pp. 217-227, 2020