带状疱疹病毒感染会增加人患痴呆症的风险吗？

诸平

据《科技日报》（scitechdaily）网站 2022年7月18日报道，美国神经病学学会（American Academy Of Neurology简称AAN）对于“带状疱疹病毒感染（Shingles Viral Infections）会增加人患痴呆症的风险吗（Do Shingles Viral Infections Increase a Person’s Risk of Dementia?）”这一疑问给出了确切地回答，答案是否定的。

带状疱疹是一种由水痘病毒（chickenpox virus）重新激活引起的病毒感染，会导致身体一侧或面部因神经炎症而出现疼痛的水疱皮疹。由于这种炎症，有科学推测带状疱疹可能会增加人患痴呆症的风险。然而，根据新研究的结果，带状疱疹与痴呆风险的增加无关。该研究于2022年6月8日已经在美国神经病学学会(AAN)的医学杂志《神经病学》（Neurology）杂志网站发表——Sigrun Alba Johannesdottir Schmidt, Katalin Veres, Henrik Toft Sørensen, Niels Obel, Victor W. Henderson. Incident Herpes Zoster and Risk of Dementia: A Population-Based Danish Cohort Study. Neurology, First Published: 8 June 2022, DOI: 10.1212/WNL.0000000000200709. https://n.neurology.org/content/early/2022/06/08/WNL.0000000000200709

参与此项研究的是丹麦（Denmark）和美国（USA）的研究人员。他们包括来自丹麦奥胡斯大学医院（Aarhus University Hospital, Denmark）、丹麦哥本哈根大学医院（Copenhagen University Hospital, Rigshospitalet, Denmark），以及美国加州斯坦福大学（Stanford University, California, USA）的研究人员。

科学家推测，带状疱疹可能会增加患痴呆症（dementia）的风险。然而，新的研究发现，带状疱疹与痴呆风险的增加无关。

丹麦奥胡斯大学医院（Aarhus University Hospital in Denmark）的医学博士希格露恩·阿尔芭·约翰内斯道蒂·施密特（Sigrun Alba Johannesdottir Schmidt）说：“随着一个人年龄的增长，他们患痴呆症的风险也在增加，确定哪些因素可能导致这种风险非常重要。带状疱疹最常影响50岁以上的人。好消息是，我们的研究发现它似乎不会增加一个人患痴呆症的风险。”

为了此研究科学家们审查了丹麦医学登记处的相关资料。他们确定了247305名曾因带状疱疹到医院就诊或接受过带状疱疹抗病毒药物治疗的人，以及1235890名年龄和性别相匹配且在20年内没有患病的人，平均年龄为64岁。

然后，研究人员检查了哪些参与者在带状疱疹诊断后长达21年发展为痴呆症。只有9.7%的带状疱疹患者最终患上了痴呆症，但是，没有带状疱疹的人群中却有10.3%的人患上了痴呆症。

在调整了糖尿病、癌症和颅脑外伤等其他健康状况后，科学家们发现，带状疱疹患者患痴呆症的风险比没有患带状疱疹的人反而低7%。

希格露恩·阿尔芭·约翰内斯道蒂·施密特说：“我们对这些结果感到惊讶。这种风险降低的原因尚不清楚，但可以通过未确诊痴呆症患者漏诊带状疱疹来解释。鼓励老年人接种带状疱疹疫苗，因为它可以预防疾病的并发症，但我们的研究表明，带状疱疹它不太可能降低痴呆症的风险。”

研究人员确实发现，带状疱疹已扩散到中枢神经系统的人患痴呆症的风险几乎增加了一倍。然而，希格露恩·阿尔芭·约翰内斯道蒂·施密特说，这种并发症很少见，影响不到 0.1% 的带状疱疹患者。

该研究存在的一个局限性就在于，参与者是根据抗病毒处方或对该疾病的医院就诊来确定的，因此对于病情较轻的人和未接受该疾病治疗的人来说，结果可能不同。

该研究得到了埃德尔和威廉·多本默克斯慈善基金会（Edel and Wilhelm Daubenmerkls Charitable Foundation）的支持。

上述介绍，仅供参考。欲了解更多信息，敬请注意浏览原文或者相关报道。

Abstract

Background and Objectives: Herpes zoster is caused by reactivation of the neurotrophic varicella-zoster virus. Zoster may contribute to development of dementia through neuroinflammation, cerebral vasculopathy, or direct neural damage, but epidemiological evidence is limited. We used data from linked nationwide Danish registries to conduct a cohort study of the association between zoster and dementia during 1997 to 2017. As secondary aims, we examined if associations were more pronounced for zoster involving cranial nerves (mainly ophthalmic zoster) or the central nervous system and Alzheimer’s disease as an outcome.

Methods: We included people aged ≥40 years with zoster and a general population comparison cohort matched 5︰1 by sex and birth year. We identified zoster and dementia in the registries using prescription records in the community and hospital diagnoses. We used Cox regression to compute confounder-adjusted hazard ratios (HR) with 95% confidence intervals (CIs) for dementia associated with zoster during 0–1 year and 1–21 years of follow-up. We compared the cumulative incidence of dementia, inverse probability-weighted for confounders.

Results: The study included 247,305 people with zoster and 1,235,890 matched general population comparators (median age 64 years; 61% female). The HR of all-cause dementia was 0.98 (95% CI: 0.92–1.04) during the first year and 0.93 (95% CI: 0.90–0.95) thereafter in people with zoster versus matched comparators. Dementia was diagnosed in 9.7% of zoster patients and 10.3% of matched comparators by end of follow-up. We observed no increased long-term risk of dementia in subgroup analyses, except possibly in people with central nervous system infection (HR 1.94; 95% CI: 0.78–4.80). Analyses of Alzheimer’s disease as a separate outcome showed similar results.

Discussion: Herpes zoster is not associated with increased risk of dementia, and contrary to expectation we found a small decrease in risk. The explanation for this finding is unclear, and systematic errors should be considered. Patients with central nervous system involvement had almost two-fold increased relative risk of dementia. The population attributable fraction of dementia due to this rare complication is estimated at 0.014%. Therefore, universal vaccination against varicella-zoster virus in the elderly is unlikely to reduce dementia risk.