Gravenstein Stefan, Dahal Roshani, Gozalo Pedro L, Davidson H Edward, Han Lisa F, Taljaard Monica, Mor Vincent
Center for Geriatrics and Palliative Care, University Hospitals Case Medical Center and Case Western Reserve University, Cleveland, OH, USA Center for Gerontology and Health Care Research, School of Public Health, Brown University, Providence, RI, USA Department of Health Services, Policy and Practice, School of Public Health, Brown University, Providence, RI, USA.
Center for Gerontology and Health Care Research, School of Public Health, Brown University, Providence, RI, USA.
Clin Trials. 2016 Jun;13(3):264-74. doi: 10.1177/1740774515625976. Epub 2016 Feb 11.
Influenza, the most important viral infection affecting older adults, produces a substantial burden in health care costs, morbidity, and mortality. Influenza vaccination remains the mainstay in prevention and is associated with reduced rates of hospitalization, stroke, heart attack, and death in non-institutional older adult populations. Influenza vaccination produces considerably lower antibody response in the elderly compared to young adults. Four-fold higher vaccine antigen (high-dose) than in the standard adult vaccine (standard-dose) elicits higher serum antibody levels and antibody response in ambulatory elderly.
To describe the design considerations of a large clinical trial of high-dose compared to standard-dose influenza vaccine in nursing homes and baseline characteristics of participating nursing homes and long-stay (more than 90 days) residents over 65 years of age.
The high-dose influenza vaccine intervention trial is multifacility, cluster randomized controlled trial with a 2×2 factorial design that compares hospitalization rates, mortality, and functional decline among long-stay nursing home residents in facilities randomized to receive high-dose versus standard-dose influenza vaccine and also randomized with or without free staff vaccines provided by study organizers. Enrollment focused on nursing homes with a large long-stay resident population over 65 years of age. The primary outcome is the resident-level incidence of hospitalization with a primary diagnosis of pulmonary and influenza-like illness, based upon Medicare inpatient hospitalization claims. Secondary outcomes are all-cause mortality based upon the vital status indicator in the Medicare Vital Status file, all-cause hospitalization directly from the nursing home Minimum Data Set discharge records, and the probability of declining at least 4 points on the 28-point Activities of Daily Living Scale.
Between February and September 2013, the high-dose influenza vaccine trial recruited and randomized 823 nursing homes. The analysis sample includes 53,035 long-stay nursing home residents over 65 years of age, representing 57.7% of the participating facilities' population. Residents are mainly women (72.2%), white (75.5%), with a mean age of 83 years. Common conditions include hypertension (79.2%), depression (55.1%), and diabetes mellitus (34.4%). The prevalence of circulatory and pulmonary disorders includes heart failure (20.5%), stroke (20.1%), and asthma/chronic obstructive pulmonary disease (20.2%).
This high-dose influenza vaccine trial uniquely offers a paradigm for future studies of clinical and programmatic interventions within the framework of efforts designed to test the impact of changes in usual treatment practices adopted by health care systems.
NCT01815268.
流感是影响老年人的最重要病毒感染，在医疗保健成本、发病率和死亡率方面造成了巨大负担。流感疫苗接种仍然是预防的主要手段，与非机构化老年人群体中住院率、中风、心脏病发作和死亡率的降低相关。与年轻人相比，流感疫苗接种在老年人中产生的抗体反应要低得多。与标准成人疫苗（标准剂量）相比，疫苗抗原剂量高四倍（高剂量）的疫苗能在非卧床老年人中引发更高的血清抗体水平和抗体反应。
描述一项在养老院中比较高剂量与标准剂量流感疫苗的大型临床试验的设计考量，以及参与试验的养老院和65岁以上长期居住（超过90天）居民的基线特征。
高剂量流感疫苗干预试验是一项多机构、整群随机对照试验，采用2×2析因设计，比较随机接受高剂量与标准剂量流感疫苗的养老院中，长期居住居民的住院率、死亡率和功能衰退情况，这些居民还被随机分为接受或不接受研究主办方提供的免费工作人员疫苗。入组重点是65岁以上长期居住居民数量较多的养老院。主要结局是根据医疗保险住院理赔记录，以肺部和流感样疾病为主要诊断的居民层面的住院发生率。次要结局包括根据医疗保险生命状态文件中的生命状态指标得出的全因死亡率、直接来自养老院最低数据集出院记录的全因住院率，以及在28分日常生活活动量表上至少下降4分的概率。
2013年2月至9月期间，高剂量流感疫苗试验招募并随机分配了823家养老院。分析样本包括53035名65岁以上的长期居住养老院居民，占参与机构人口的57.7%。居民主要为女性（72.2%），白人（75.5%），平均年龄83岁。常见疾病包括高血压（79.2%）、抑郁症（55.1%）和糖尿病（34.4%）。循环系统和肺部疾病的患病率包括心力衰竭（20.5%）、中风（20.1%）和哮喘/慢性阻塞性肺疾病（20.2%）。
这项高剂量流感疫苗试验独特地为未来在旨在测试医疗保健系统采用的常规治疗方法变化影响的努力框架内进行的临床和项目干预研究提供了一个范例。
NCT01815268。
