中国2009-2010年18岁以下人群甲型H1N1流感相关肺炎住院病例危险因素分析

Risk factors for influenza A （H1N1） -associated pneumonia on hospitalized people less than 18 years old in China, 2009-2010

目的描述2009--2010年中国〈18岁人群甲型H1N1流感（甲流）相关肺炎住院病例的临床和流行病学特征，分析并发肺炎的危险因素。方法对2009年9月1日至2010年7月4日中国“甲型H1N1流感信息管理系统”甲流住院病例（〈18岁）个案数据进行分析，描述其人口学、临床治疗、并发症、慢性基础性疾病等特征，分为并发与未并发肺炎2组进行单因素和多因素logistic分析。结果共得到4240份甲流相关住院病例个案数据，其中4107例有“是否并发肺炎”方面的信息[2289例（55．7％）并发肺炎]。甲流相关肺炎住院病例年龄中位数低于未并发肺炎者（4．9：13．1，P〈0．0001），且出现呼吸窘迫综合征、呼吸衰竭、需要ICU治疗、需要机械通气治疗以及出现死亡的风险均显著增加（P〈0．0001）。多因素分析显示，与5～17岁人群相比，〈6月龄（OR=7．08，95％CI：4．15—12．06）、6—23月龄（aOR=8．26，95％CI：6．10—11．20）及2～4岁（aOR=9．53，95％CI：7．39～12．29）甲流相关住院病例并发肺炎的危险显著增高；哮喘（OR=12．19，95％CI：5．18～28．72）、心血管疾病（OR=5．19，95％CI：1．94～13．90）、慢性肾脏疾病（OR=2．14，95％CI：1．02～4．53）、慢性肝脏疾病（0R=5．26，95％CI：1．40—19．81）及过敏（OR=2．54，95％CI：1．64～3．93）是〈18岁人群甲流住院病例并发肺炎的危险因素；与发病到抗病毒药物治疗的时间间隔不超过2d相比，时间间隔3～4d（OR=1．85，95％CI：1．45—2．36，P〈0．0001）、超过4d（OR=2．91，95％CI：2．29—3．71，P〈0．0001）显著增加并发肺炎的危险。结论甲流相关住院病例并发肺炎的比例很高。与未并发肺炎者相比，甲流相关肺炎住院病例的病程更长和转归较差。

Objective To describe the epidemiological and clinical features of hospitalized people less than 18 years old with influenza A （H1N1）-associated pneumonia and associated risk factors. Methods Through Chinese Reporting System of Influenza A（H1N1 ）, children aged under 18 years who were hospitalized with laboratory confirmed influenza A （H1N1）, case report forms and related information on pneumonia were collected between 1 September 2009 and 4 July 2010. Epidemiologieal and clinical characteristics including demographics, underlying chronic diseases, treatment, complications and clinical outcome etc. were described. Hospitalized children with pneumonia were compared with those without the above mentioned features, through the univariate and multivariate analysis. Results There were 4240 influenza A （H1N1） -associated hospitalized children with case report forms identified. Of the 4107 influenza A （H1N1）-associated hospitalized children with related information on pneumonia shown in the case report forms, 2289 （55.7%） of them had pneumonia. Hospitalized children with influenza A（H1N1 ） -associated pneumonia had a younger median age （4.9year old）, when compared with those without pneumonia （ 13.1 year old, P〈 0.0001 ）. When compared with the hospitalized children without pneumonia, those hospitalized children with pneumonia were more likely to require intensive care unit care, using mechanical ventilation epuipmentto develop ARDS, respiratory failure or leading to death. Data from multivariate analysis showed that children aged 〈6 months （OR=7.08,95%CI：4.15-12.06） between 6 and 23 months （aOR=8.26,95%CI： 6.10-11.20） or between 2 to 4 year old （aOR=9.53,95%CI： 7.39-12.29） were more likely to develop pneumonia than children aged 5 to 17. Factors as having asthma （0R=12.19, 95% CI： 5.18-28.72） , cardiovascular disease （0R=5.19, 95% CI： 1.94-13.90） , chronic renal diseases （0R=2.14, 95% CI： 1.02-4.53） , chronic hepatic diseases （OR=5.26, 95%CI： 1.40-19.81） and allergy （OR=2.54, 95%CI： 1.64-3.93） were significantly associated with influenza A （H 1N 1 ） -associated pneumonia. Risk of complication with pneumonia had an increase when oseltamivir treatment was initiated 〉2 days after the onset of illness. Conclusion Pneumonia was a common complication among children hospitalized with influenza A （H1N1）. Hospitalized children with influenza A （H1N1） -associated pneumonia were more likely to develop either severe clinical courses or outcomes than those without pneumonia.