A new study by Aarhus University and Aarhus University Hospital has found that elderly people who have been admitted to an intensive care units have less risk of dying and of suffering a blood clot or bleeding in the brain if they have been vaccinated for the flu.

The data showed that for those who were vaccinated the risk of suffering a stroke was 16% lower than those who weren’t, as well as the vaccinated group having an 8% lower risk of dying during the first year following their hospitalisation.

“Every year, 30,000 people are admitted to the intensive care units in Danish hospitals and we know that the first year is critical,” explained says Christian Fynbo Christiansen, clinical associate professor at Aarhus University Hospital and consultant at Aarhus University Hospital.

He continued, “three out of four survive the hospitalisation and are discharged from hospital. But even among the patients who are discharged, almost one in five die within the first year while many others suffer complications. Our study shows that there are fewer deaths and serious complications among the patients who have been vaccinated against influenza. So this supports the current recommendation that elderly people should be vaccinated.”

Surprisingly, however, the vaccine “didn’t reduce the number of pneumonia cases in our study”, despite expectations that it would, as “some previous studies have shown that the vaccine has this effect on younger and healthy individuals.”

The study is a register-based cohort study that covered 89,818 patients who survived hospitalisation in intensive care departments in Denmark during the period 2005-2015, and was carried out with support from the Independent Research Fund Denmark and PROCRIN (the Program for Clinical Research Infrastructure).