Project #209: SARS COVID-19 vaccination and risk of major adverse cardiac events after hip fracture

Hip fractures resulting from minimal trauma are common and are a major contributor to early death. Around 1 in 4 adults over the age of 50 that have a broken hip die within 12 months. The leading causes of death in this group of people are cardiovascular deaths (heart attacks and strokes). Despite this, there is no specific strategy in the standard of care that addresses this known risk for these people.
Evidence conducted in people who have had a heart attack show that having a COVID or flu vaccine (either in the recent past, or in the days after the event), end up having fewer heart attacks in the future. These vaccines are thought to ‘desensitise’ the immune system such that if/when someone gets another viral infection, it produces a less potent immune system response. Therefore, during an infection there is less stress on the heart and so the risk of having another heart attack is reduced. In a similar way, having a hip fracture also causes an enormous stress on the heart, and this is probably why heart attacks are so common after a hip fracture.

Therefore, we are proposing to study if having a COVID vaccine before or immediately after a hip fracture results in fewer heart attacks after the hip fracture compared with people who have not had a vaccine recently. We will also study if the effects are comparable to having a flu vaccine, and whether there is some time-limiting effect where any observed benefit wears off and so this would mean having up to date vaccines could be recommended. Ultimately, our study will help shape health policy about how best to manage people with hip fractures to prevent heart attacks and save lives.