Manufacturers say the flu vaccine for this season is much more effective than last year’s. However, two new studies suggest flu vaccines in general may not work as well if you take statins.
In this edition of Vital Signs, Dr. Jeffrey Kahn, Chief of Pediatric Infectious Diseases at UT Southwestern Medical Center, says the studies aren't definitive, but the results are provocative.
Highlights from Dr. Kahn’s interview:
About the studies: “We’ve known for a long time that statins, which are used to reduce cholesterol and reduce the risk coronary artery disease, also have effects on inflammation and immune responses, so we know statins can be anti-inflammatory. So the questions came up, whether people who are receiving statins would have a diminished response to vaccines and these two studies specifically looked at influenza vaccine.”
First Study: “One (study) angle was looking at a vaccine trial where they were comparing individuals who were receiving statins to those who weren’t receiving statins. It appeared that the response to the influenza vaccine was less robust in those taking statins than in those who didn’t. You have to be cautious how we interpret this It could be these two groups weren’t equal. It could be the people taking statins had more underlying illnesses which may impair their response to influenza vaccine. Or that individuals who didn’t take statins were healthier and, therefore, had a greater response to the vaccine.”
Second study: “The second study looked at it from a very different angle – individuals who had respiratory illnesses. And again, they saw those were receiving statins seem to have more of these medical attendant acute respiratory infections, suggesting that the vaccine efficacy in these patients was lower. We don’t know if the two groups were equivalent. It could be people were going to the doctor because of underlying illnesses. We don’t know prior histories of a lot of these patients."
In conclusion: “The jury’s still out. The bottom line is continue to take your statins and continue to get your flu shots.”
For more information:
Two reports on flu shots & statins: