By Yun Lu, Yoganand Chillarige, Hector S Izurieta, Yuqin Wei, Wenjie Xu, Michael Lu, Heng-Ming Sung, Arnstein Lindaas, Michael Wernecke, Thomas Macurdy, Jeffrey Kelman, Richard A Forshee. Published in The Journal of Infectoius Diseases. To be published November 1, 2019.
Studies have found that the high-dose influenza vaccine has a higher relative vaccine effectiveness (rve) versus standard-dose vaccines in some seasons. We evaluated the effect of age on the rve of high-dose versus standard-dose influenza vaccines among medicare beneficiaries. A 6-season retrospective cohort study from 2012 to 2018 among medicare beneficiaries aged ≥65 years was performed. Poisson regression was used to evaluate the effect of age on the rve of high-dose versus standard-dose influenza vaccines in preventing influenza-related hospitalizations.The study included >19 million vaccinated beneficiaries in a community pharmacy setting. The poisson models indicated a slightly increasing trend in rve with age in all seasons. The high-dose vaccine was more effective than standard-dose vaccines in preventing influenza-related hospital encounters (ie, influenza-related inpatient stays and emergency department visits) in the 2012–2013 (rve, 23.1%; 95% confidence interval [ci], 17.6%–28.3%), 2013–2014 (rve, 15.3%; 95% ci, 7.8%–22.3%), 2014–2015 (rve, 8.9%; 95% ci, 5.6%–12.1%), and 2016–2017 (rve, 12.6%; 95% ci, 6.3%–18.4%) seasons and was at least as effective in all other seasons. We also found that the high-dose vaccine was consistently more effective than standard-dose vaccines across all seasons for people aged ≥85 years. Similar trends were observed for influenza-related inpatient stays. The rve of high-dose versus standard-dose influenza vaccines increases with age.
Access article here.