title: Habitual coffee consumption and risk of cognitive decline/dementia: A systematic review and meta-analysis of prospective cohort studies.
abstract: OBJECTIVE
  Findings from epidemiologic studies of coffee consumption and risk for cognitive decline or dementia are inconclusive. The aim of this study was to conduct a meta-analysis of prospective studies to assess the association between coffee consumption and the risk for cognitive decline and dementia.
  
  
  METHODS
  Relevant studies were identified by searching PubMed and Embase databases between 1966 and December 2014. Prospective cohorts that reported relative risk (RRs) and 95% confidence intervals (CIs) for the association of coffee consumption with dementia incidence or cognitive changing were eligible. Study-specific RRs were combined by using a random-effects model.
  
  
  RESULTS
  Eleven prospective studies, including 29,155 participants, were included in the meta-analysis. The combined RR indicated that high coffee consumption was not associated with the different measures of cognitive decline or dementia (summary RR, 0.97; 95% CI, 0.84-1.11). Subgroup analyses suggested a significant inverse association between highest coffee consumption and the risk for Alzheimer disease (summary RR, 0.73; 95% CI, 0.55-0.97). The dose-response analysis, including eight studies, did not show an association between the increment of coffee intake and cognitive decline or dementia risk (an increment of 1 cup/d of coffee consumed; summary RR, 1.00; 95% CI, 0.98-1.02).
  
  
  CONCLUSIONS
  The present study suggests that higher coffee consumption is associated with reduced risk for Alzheimer disease. Further randomized controlled trials or well-designed cohort studies are needed to determine the association between coffee consumption and cognitive decline or dementia.
authors.affiliation: Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China; Department of Neurology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
authors.forename: Qing-Ping
authors.initials: QP
authors.lastname: Liu
authors.affiliation: Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China; Department of Neurology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
authors.forename: Yan-Feng
authors.initials: YF
authors.lastname: Wu
authors.affiliation: Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
authors.forename: Hong-Yu
authors.initials: HY
authors.lastname: Cheng
authors.affiliation: Department of Pediatrics, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Xia
authors.affiliation: Department of Neurology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Ding
authors.affiliation: Department of Neurology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China.
authors.forename: Ze-Mu
authors.initials: ZM
authors.lastname: Wang
authors.affiliation: Department of Neurology, Drum Tower Hospital of Nanjing Medical University, Nanjing, Jiangsu, People's Republic of China. Electronic address: Xuyun20042001@aliyun.com.
authors.forename: Yun
authors.initials: Y
authors.lastname: Xu
mesh_terms: D003069:Coffee; D060825:Cognitive Dysfunction / Q000453:epidemiology*; D003704:Dementia / Q000453:epidemiology*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D003069:Coffee
keywords: Alzheimer disease; Coffee consumption; Cognitive decline; Dementia; Meta-analysis