Joint Corticosteroid Injection Associated With Increased Influenza Risk.

Aging and immunocompromising conditions or medications may reduce influenza vaccine effectiveness. The high-dose vaccine has been used to improve vaccine response in patients 65 years and older. Because of systemic immunosuppressive effects, oral corticosteroids may reduce vaccine effectiveness; however, despite over half a century of use, no data are available regarding the effect of joint and bursa corticosteroid injection on influenza vaccine effectiveness. The aim of this retrospective study was to determine whether joint corticosteroid injection was associated with reduced influenza vaccine effectiveness. During the 5 influenza seasons between August 1, 2012, and March 31, 2017, a total of 15,068 major joint corticosteroid injections were given to patients residing in Olmsted County, Minnesota. Vaccinated patients receiving a major joint corticosteroid injection (n=4804) were at increased risk (relative risk, 1.52; 95% CI, 1.20-1.93) for developing influenza compared with vaccinated control patients. Women younger than 65 years were at the highest risk, suggesting that perhaps the high-dose vaccine should be considered for this group to enhance protection when possible.