Saah A J, Neufeld R, Rodstein M, La Montagne J R, Blackwelder W C, Gross P, Quinnan G, Kaslow R A
Arch Intern Med. 1986 Dec;146(12):2353-7.
The effectiveness of immunization against influenza in elderly persons is uncertain. A retrospective cohort study in a New York City nursing home examined the occurrence of pneumonia and its related mortality over three consecutive influenza seasons (Nov 1 through April 30, 1979 to 1980, 1980 to 1981, and 1981 to 1982). Nearly one half of approximately 450 residents (mean age, 84 years) accepted immunization each year. The vaccinated and unvaccinated groups were similar. The attack rate of pneumonia did not differ significantly between the vaccinated and unvaccinated groups in any of the three influenza seasons. When influenza was occurring in the community (1979 to 1980 and 1980 to 1981), however, the risk of death from pneumonia in the unvaccinated group was three-fold higher than in the vaccinated group (60% vs 18% and 73% vs 25%, respectively). In a year when influenza was specifically sought and not found in the facility (1981 to 1982), however, vaccination did not affect pneumonia-related mortality. This study also suggests that estimates of mortality due to pneumonia should include deaths that occur up to 60 days after onset of pneumonia; shorter follow-up may overestimate the protective effect of vaccination.
流感疫苗对老年人的有效性尚不确定。纽约市一家养老院进行的一项回顾性队列研究，调查了连续三个流感季节（1979年11月1日至1980年4月30日、1980年至1981年、1981年至1982年）肺炎的发生情况及其相关死亡率。在约450名居民（平均年龄84岁）中，每年有近一半的人接受了疫苗接种。接种疫苗组和未接种疫苗组情况相似。在三个流感季节中的任何一个季节，接种疫苗组和未接种疫苗组的肺炎发病率均无显著差异。然而，当社区出现流感时（1979年至1980年和1980年至1981年），未接种疫苗组因肺炎死亡的风险比接种疫苗组高两倍（分别为60%对18%和73%对25%）。然而，在某一年度，该养老院特意寻找但未发现流感（1981年至1982年），接种疫苗对肺炎相关死亡率没有影响。这项研究还表明，肺炎所致死亡率的估计应包括肺炎发病后60天内发生的死亡；随访时间较短可能会高估疫苗接种的保护作用。
