Vaccines with four times the antigen of standard flu vaccines significantly decrease the risk of respiratory and all-cause hospitalizations during flu season, according to the largest nursing home study conducted to date on the effect of a high dose flu vaccine.

Respiratory illness hospitalizations decreased by 12.7%, and all-cause hospitalizations fell by 8.5% during the study period. The imputed cost savings are significant, experts said.

Research was conducted on 38,000 nursing home residents 65 and older across 38 states. All participants were on Medicare and received high-dose flu vaccines instead of standard doses.

The flu annually affects more than four million adults ages 65 and older and is a major cause of hospitalization for the nursing home population. Associated costs total $8.3 billion, study authors said.

“If given to all approximately 1.5 million nursing home residents, a one percent drop in hospitalizations would translate to thousands fewer being hospitalized,” said Stefan Gravenstein, MD, MPH, lead author of the study. “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.”

The study is the first randomized and controlled prospective study that demonstrates how effective the high-dose flu vaccine is in reducing respiratory-related hospitalization for the nursing home population compared to the standard dose, said Gravenstein. In order for the higher dose to become the preferred procedure for nursing homes the ACIP, which is a group of medical and public health experts who develop the recommendations for vaccine use, would need to determine this is the correct course of action.

Study findings were published by researchers at the University Hospitals Cleveland Medical Center on Thursday in the journal The Lancet Respiratory Medicine