Nursing home residents see drop in hospitalization rate following high-dose flu vaccine

New findings published in The Lancet Respiratory Medicine show that a high-dose (HD) influenza vaccine significantly reduced the risk of respiratory and all-cause hospitalization during flu season when compared with the standard-dose (SD) vaccine.

The study was the largest nursing home study to date to study the effects of the HD vaccine, which contains four times the antigen of the SD dose.

All told, there was a 12.7% relative reduction in the hospitalization for respiratory illnesses, including pneumonia, and an 8.5% reduction of all-cause hospitalizations among residents on Medicare who reside in nursing homes and who received the higher dose.

“Our study is the first randomized, controlled prospective study to demonstrate the comparative effectiveness of the influenza vaccine in reducing respiratory-related hospitalization in a very frail, long-stay nursing home population,” said Stefan Gravenstein, MD, MPH, lead author of the study. He is on the faculty at the Warren Alpert Medical School at Brown University and at University Hospitals Cleveland Medical Center and Case Western Reserve University School of Medicine.

“Our finding that the high dose vaccination is more effective than a standard dose in reducing hospitalizations is remarkable for several reasons. For one, the flu season’s predominant circulating strain was one where benefit to older adults from vaccination had been questioned,” said Dr. Gravenstein. “The fact that we observed a lower rate of hospitalization from all causes, too, suggests that vaccine offers protection beyond flu-related outcomes, perhaps including heart and other conditions.”

He added that if the HD vaccine was administered to all of the approximately 1.5 million nursing home residents, the 1% decrease in hospitalizations would translate into thousands of patients that would not require hospitalization.

The Centers for Disease Control and Prevention (CDC) reports that the risk of hospitalization is one in five during the flu season, which is the same number arrived at in this study.

The study followed more than 38,000 participants aged 65 years and older who resided in 823 nursing homes in 38 states. Two FDA-licensed influenza vaccines that were recommended by the Advisory Committee on Immunization Practices (ACIP) for older nursing home residents were used. Nursing homes in the study were randomly assigned to either HD or SD for residents.

“In our study, we estimated that for every 84 individuals receiving the high dose vaccine, a person was prevented from being hospitalized during the influenza season,” Dr. Gravenstein said.

The ACIP is now tasked with determining whether the higher dose becomes the preferred procedure for nursing homes. The ACIP is a group of medical and public health experts that develop recommendations on use of vaccines in the civilian population.

The study was funded through an investigator-initiated grant by Sanofi Pasteur.

To read more about the study, click here.