Department of Medicine and Therapeutics, Prince of Wales Hospital, Chinese University of Hong Kong, Peoples Republic of China.
J Infect Dis. 2011 Jun 15;203(12):1739-47. doi: 10.1093/infdis/jir187.
It is unclear whether pandemic 2009 influenza A (pH1N1) infection caused more significant disease among hospitalized adults than seasonal influenza.
A prospective, observational study was conducted in adults hospitalized with polymerase chain reaction-confirmed pH1N1 infection in 2 acute-care general hospitals from June 2009 to May 2010 (n = 382). Complications and outcomes were described and compared with those in a seasonal influenza cohort (2007-2008, same hospitals; n = 754).
Hospitalized patients with pH1N1 influenza were younger than those with seasonal influenza (mean age ± standard deviation, 47 ± 20 vs 70 ± 19 years) and fewer had comorbid conditions (48% vs 64%). The rate of positive immunofluorescence assay results was low (54% vs 84%), and antiviral use was frequent (96% vs 52%). Most patients in both cohorts developed complicated illnesses (67.8% vs 77.1%), but patients with pH1N1 influenza had higher rates of extrapulmonary complications (23% vs 16%; P = .004) and intensive care unit admission and/or death (patient age <35 years, 2.3% vs 0%; 35-65 years, 12.4% vs 3.2%; >65 years, 13.5% vs 8.5%; adjusted odds ratio [OR] 2.13; 95% confidence interval [CI], 1.25-3.62; P = .005). Patients who received antiviral treatment within 96 h after onset had better survival (log-rank test, P < .001). However, without timely treatment, the mortality risk was higher with pH1N1 infection (9.0% vs 5.8% for seasonal influenza; adjusted OR, 6.85; 95% CI, 1.64-28.65; P = .008]. Bacterial superinfection worsened outcomes.
Adults hospitalized for pH1N1 influenza had significant complications and mortality despite being younger than patients with seasonal influenza. Antiviral treatment within 96 h may improve survival.
尚不清楚 2009 年甲型流感（pH1N1）大流行感染是否比季节性流感导致住院成人患者病情更严重。
本前瞻性观察性研究于 2009 年 6 月至 2010 年 5 月在两家急性护理综合医院对经聚合酶链反应确诊为 pH1N1 感染的住院成人患者（n=382）进行了开展。对并发症和结局进行了描述，并与季节性流感队列（2007-2008 年，同家医院；n=754）进行了比较。
感染 pH1N1 流感的住院患者比感染季节性流感的患者年龄更小（平均年龄±标准差，47±20 岁 vs 70±19 岁），合并症更少（48% vs 64%）。免疫荧光检测结果阳性率较低（54% vs 84%），抗病毒药物使用率较高（96% vs 52%）。两个队列的大多数患者均发生了并发症（67.8% vs 77.1%），但感染 pH1N1 流感的患者更易发生肺外并发症（23% vs 16%；P=0.004），入住重症监护病房和/或死亡的比例更高（患者年龄<35 岁，2.3% vs 0%；35-65 岁，12.4% vs 3.2%；>65 岁，13.5% vs 8.5%；调整后的比值比[OR]2.13；95%置信区间[CI]1.25-3.62；P=0.005）。发病后 96 小时内接受抗病毒治疗的患者生存情况更好（对数秩检验，P<0.001）。然而，未及时治疗的情况下，pH1N1 感染的死亡率更高（9.0% vs 5.8%；季节性流感；调整后的 OR，6.85；95%CI，1.64-28.65；P=0.008）。细菌合并感染会加重结局。
尽管感染 pH1N1 流感的成年人比感染季节性流感的成年人年龄更小，但仍会发生严重并发症和死亡。发病后 96 小时内进行抗病毒治疗可能会改善生存。
