Dataset Information

Head Injury as a Risk Factor for Dementia and Alzheimer's Disease: A Systematic Review and Meta-Analysis of 32 Observational Studies.

ABSTRACT:

Background

Head injury is reported to be associated with increased risks of dementia and Alzheimer's disease (AD) in many but not all the epidemiological studies. We conducted a systematic review and meta-analysis to estimate the relative effect of head injury on dementia and AD risks.

Methods

Relevant cohort and case-control studies published between Jan 1, 1990, and Mar 31, 2015 were searched in PubMed, Web of Science, Scopus, and ScienceDirect. We used the random-effect model in this meta-analysis to take into account heterogeneity among studies.

Results

Data from 32 studies, representing 2,013,197 individuals, 13,866 dementia events and 8,166 AD events, were included in the analysis. Overall, the pooled relative risk (RR) estimates showed that head injury significantly increased the risks of any dementia (RR = 1.63, 95% CI 1.34-1.99) and AD (RR = 1.51, 95% CI 1.26-1.80), with no evidence of publication bias. However, when considering the status of unconsciousness, head injury with loss of consciousness did not show significant association with dementia (RR = 0.92, 95% CI 0.67-1.27) and AD (RR = 1.49, 95% CI 0.91-2.43). Additionally, this positive association did not reach statistical significance in female participants.

Conclusions

The findings from this meta-analysis indicate that head injury is associated with increased risks of dementia and AD.

SUBMITTER: Li Y

PROVIDER: S-EPMC5221805 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Publications

Head Injury as a Risk Factor for Dementia and Alzheimer's Disease: A Systematic Review and Meta-Analysis of 32 Observational Studies.

Li Yanjun Y Li Yongming Y Li Xiaotao X Zhang Shuang S Zhao Jincheng J Zhu Xiaofeng X Tian Guozhong G

PloS one 20170109 1

<h4>Background</h4>Head injury is reported to be associated with increased risks of dementia and Alzheimer's disease (AD) in many but not all the epidemiological studies. We conducted a systematic review and meta-analysis to estimate the relative effect of head injury on dementia and AD risks.<h4>Methods</h4>Relevant cohort and case-control studies published between Jan 1, 1990, and Mar 31, 2015 were searched in PubMed, Web of Science, Scopus, and ScienceDirect. We used the random-effect model i ...[more]

PMID: 28068405

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Project description:BackgroundHypertension is very common in older people and a number of trials of antihypertensives have demonstrated benefit from treatment in even the oldest old. However, people with dementia were significantly under-represented in these studies and as a population are more likely to be physically frail, to suffer orthostatic hypotension and to experience adverse effects from polypharmacy at a lower drug count. It may be that different thresholds for commencement and cessation of treatment should be considered and may already be used for this group. Against this background this review sets out to describe the prevalence of hypertension in people with dementia, its treatment, change in treatment over time and the achievement of blood pressure (BP) control.MethodsThe PubMed, Cochrane, Embase and PsychINFO databases were searched for observational studies involving people with dementia and a diagnosis of hypertension. The search was limited to English language articles involving adults and humans published from 1990 onwards. Abstracts and titles were then reviewed with eligible articles read in full. Bibliographies were examined for further relevant studies. The final selection of studies was then analysed and appraised.ResultsThirteen articles were identified for analysis. The prevalence of hypertension in people with dementia was 45% (range 35%-84%). 73% of these were on at least one antihypertensive, with diuretics being the most common. The reported prevalence of hypertension in study populations remained unchanged over time. ACEi/ARBs and calcium channel blockers were prescribed more frequently in more recent studies whilst use of β-blockers and diuretics remained unchanged. Target blood pressure was achieved in 55% of those on treatment.ConclusionHypertension is as common in people with dementia as in other populations and is as commonly treated with antihypertensive drugs. The findings presented here will support further work to establish the risk-benefit of antihypertensive treatment in patients with dementia and, if differing ratios are identified, to establish dementia-specific guidelines for management.

Dataset Information

Head Injury as a Risk Factor for Dementia and Alzheimer's Disease: A Systematic Review and Meta-Analysis of 32 Observational Studies.

Background

Methods

Results

Conclusions

Publications

Head Injury as a Risk Factor for Dementia and Alzheimer's Disease: A Systematic Review and Meta-Analysis of 32 Observational Studies.

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