Jackson Alan C, Mostaço-Guidolin Luiz C, Sinnock Hasantha, Bozat-Emre Songul, Routledge Michael, Mahmud Salaheddin M
1Department of Internal Medicine (Neurology), Faculty of Health Sciences,University of Manitoba,Winnipeg,MB,Canada.
3Department of Community Health Sciences (Vaccine and Drug Evaluation Centre), Faculty of Health Sciences,University of Manitoba,Winnipeg,MB,Canada.
Can J Neurol Sci. 2016 Nov;43(6):819-823. doi: 10.1017/cjn.2016.291. Epub 2016 Sep 9.
An increased incidence of hospital admissions coded as acute disseminated encephalomyelitis (ADEM) was noted in Winnipeg, Manitoba, Canada, during the second wave of the influenza pandemic from October 2009 to March 2010. However, it was not clear whether this was due to heightened awareness of potential neurological complications of influenza or influenza vaccination or an actual increase in the number of cases.
We extracted data from the charts of 139 patients hospitalized with an International Classification of Diseases-10 discharge code indicating ADEM (G04.0) or unspecified noninfectious encephalitis or myelitis (G04.8, G04.9) between January 2006 and December 2012. Clinical and laboratory data were reviewed by a neurologist, and diagnoses were determined using the Brighton criteria.
Over the entire study period, there were 22 cases of ADEM. During the peak pandemic period (April-December 2009), seven patients were hospitalized with ADEM, corresponding to a rate of 7.8/million/year; 4.7 (95% confidence interval: 1.9-11.4) times higher than the rate before or after the pandemic period. Only one patient with ADEM had received the monovalent A(H1N1)pdm09 vaccine within 12 weeks of hospitalization.
We have found an increased incidence of ADEM during the pandemic period that may be related, at least in part, to the increased incidence of influenza during that period. However, there was no temporal relationship with the administration of A(H1N1)pdm09 or seasonal influenza vaccines. Our study provides reassurance that use of these vaccines was not associated with increased risk of ADEM.
在加拿大曼尼托巴省温尼伯市，2009年10月至2010年3月流感大流行的第二波期间，编码为急性播散性脑脊髓炎（ADEM）的住院率有所上升。然而，尚不清楚这是由于对流感潜在神经并发症或流感疫苗接种的认识提高，还是实际病例数增加所致。
我们从2006年1月至2012年12月期间因国际疾病分类第10版出院编码显示为ADEM（G04.0）或未特指的非感染性脑炎或脊髓炎（G04.8、G04.9）而住院的139例患者的病历中提取数据。一位神经科医生对临床和实验室数据进行了审查，并使用布莱顿标准确定诊断。
在整个研究期间，有22例ADEM病例。在大流行高峰期（2009年4月至12月），有7例患者因ADEM住院，对应发病率为7.8/百万/年；比大流行期之前或之后的发病率高4.7（95%置信区间：1.9 - 11.4）倍。只有1例ADEM患者在住院12周内接种了单价A(H1N1)pdm09疫苗。
我们发现大流行期间ADEM发病率增加，这可能至少部分与该期间流感发病率增加有关。然而，与A(H1N1)pdm09或季节性流感疫苗的接种并无时间关联。我们的研究表明这些疫苗的使用与ADEM风险增加无关，令人安心。
