Warren-Gash Charlotte, Forbes Harriet, Breuer Judith, Hayward Andrew C, Mavrodaris Angelique, Ridha Basil H, Rossor Martin, Thomas Sara L, Smeeth Liam
Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
Division of Infection and Immunity, University College London, London, UK.
BMJ Open. 2017 Jun 23;7(6):e016522. doi: 10.1136/bmjopen-2017-016522.
Persisting neurotropic viruses are proposed to increase the risk of dementia, but evidence of association from robust, adequately powered population studies is lacking. This is essential to inform clinical trials of targeted preventive interventions.
We will carry out a comprehensive systematic review of published and grey literature of the association between infection with, reactivation of, vaccination against or treatment of any of the eight human herpesviruses and dementia or mild cognitive impairment. We will search the Cochrane Library, Embase, Global Health, Medline, PsycINFO, Scopus, Web of Science, clinical trials registers, the New York Academy of Medicine Grey Literature Report, Electronic Theses Online Service through the British Library and the ISI Conference Proceedings Citation Index for randomised controlled trials, cohort, caseâ€"control, case crossover or self-controlled case series studies reported in any language up to January 2017. Titles, abstracts and full-text screening will be conducted by two researchers independently. Data will be extracted systematically from eligible studies using a piloted template. We will assess risk of bias of individual studies in line with the Cochrane Collaboration tool. We will conduct a narrative synthesis, grouping studies by exposure and outcome definitions, and will describe any differences by population subgroups and dementia subtypes. We will consider performing meta-analyses if there are adequate numbers of sufficiently homogeneous studies. The overall quality of cumulative evidence will be assessed using selected Grading of Recommendations, Assessment, Development and Evaluations criteria.
As this is a review of existing studies, no ethical approval is required. Results will be disseminated through a peer-reviewed publication and at national and international conferences. We anticipate the review will clarify the current extent and quality of evidence for a link between herpesviruses and dementia, identify gaps and inform the direction of future research.
CRD42017054684.
持续性嗜神经病毒被认为会增加患痴呆症的风险，但缺乏来自有力的、有足够样本量的人群研究的关联证据。这对于为针对性预防干预的临床试验提供信息至关重要。
我们将对已发表文献和灰色文献进行全面系统的综述，内容涉及八种人类疱疹病毒中的任何一种的感染、再激活、疫苗接种或治疗与痴呆症或轻度认知障碍之间的关联。我们将检索Cochrane图书馆、Embase、全球卫生数据库、Medline、PsycINFO、Scopus、科学网、临床试验注册库、纽约医学院灰色文献报告、通过大英图书馆的电子论文在线服务以及ISI会议论文引文索引，以查找截至2017年1月以任何语言发表的随机对照试验、队列研究、病例对照研究、病例交叉研究或自我对照病例系列研究。两名研究人员将独立进行标题、摘要和全文筛选。将使用预先试验的模板从符合条件的研究中系统提取数据。我们将根据Cochrane协作工具评估各个研究的偏倚风险。我们将进行叙述性综合分析，按暴露和结果定义对研究进行分组，并描述人群亚组和痴呆症亚型之间的任何差异。如果有足够数量的充分同质的研究，我们将考虑进行荟萃分析。将使用选定的推荐分级、评估、制定和评价标准评估累积证据的总体质量。
由于这是对现有研究的综述，无需伦理批准。研究结果将通过同行评审出版物以及在国内和国际会议上进行传播。我们预计该综述将阐明目前疱疹病毒与痴呆症之间联系的证据范围和质量，找出差距并为未来研究方向提供信息。
PROSPERO注册号：CRD42017054684。
