CSL Seqirus, Center for Outcomes Research and Epidemiology, Waltham, Massachusetts, USA.
Veradigm, Real World Evidence, Chicago, Illinois, USA.
Clin Infect Dis. 2024 Sep 26;79(3):778-786. doi: 10.1093/cid/ciae180.
Research on influenza burden in adults has focused on crude subgroups with cut-points at 65 years, limiting insight into how burden varies with increasing age. This study describes the incidence of influenza-related outpatient visits, emergency room visits, and hospitalizations, along with healthcare resource use and complications in the aging adult population.
Individuals aged ≥18 years in the United States were evaluated retrospectively in 5 seasonal cohorts (2015-2020 seasons) in strata of age with 5-year increments. Person-level electronic medical records linked to pharmacy and medical claims were used to ascertain patient characteristics and outcomes. Influenza-related medical encounters were identified based on diagnostic codes (International Classification of Diseases, 10th Edition, codes J09*-J11*).
Incidence of influenza-related outpatient visits was highest among people aged 18-34 years and declined with increasing age. For emergency room visits, incidence tended to be elevated for people aged 18-34 years, relatively stable from 35 through 60, and increased rapidly after age 60 years. Hospitalization incidence remained relatively stable until about 50 years of age and then increased with age. One in 3 patients was diagnosed with pneumonia after hospitalization, regardless of age. Across seasons, age groups, and clinical settings, on average, 40.8% of individuals were prescribed antivirals and 17.2% antibiotics.
Incidence of influenza-related hospitalizations begins to increase around age 50 years rather than the more common cut-point of 65, whereas incidence of outpatient visits was highest among younger adults. Influenza infections frequently led to antiviral and antibiotic prescriptions, underscoring the role influenza vaccination can play in combating antimicrobial resistance.
成人流感负担的研究主要集中在以 65 岁为截定点的粗分组上，这限制了对负担随年龄增长而变化的深入了解。本研究描述了与流感相关的门诊就诊、急诊就诊和住院治疗的发生率，以及老龄化人群中医疗资源的使用和并发症情况。
在美国，对年龄在 18 岁及以上的个体在 5 个季节性队列（2015-2020 季节）中进行回顾性评估，分为 5 岁一个年龄组。使用个人电子病历与药房和医疗索赔记录相链接，以确定患者特征和结局。基于诊断代码（国际疾病分类，第 10 版，代码 J09*-J11*）确定与流感相关的医疗接触。
与流感相关的门诊就诊发生率在 18-34 岁人群中最高，随着年龄的增长而下降。对于急诊就诊，18-34 岁人群的发病率较高，35-60 岁之间相对稳定，60 岁以后迅速增加。住院治疗的发病率在 50 岁左右之前相对稳定，然后随年龄增长而增加。无论年龄大小，三分之一的住院患者被诊断为肺炎。在整个季节、年龄组和临床环境中，平均有 40.8%的患者开具了抗病毒药物，17.2%的患者开具了抗生素。
与流感相关的住院治疗发生率在 50 岁左右开始增加，而不是常见的 65 岁截定点，而门诊就诊的发生率在年轻成人中最高。流感感染经常导致抗病毒药物和抗生素处方，这突出了流感疫苗在对抗抗生素耐药性方面的作用。
