(264) Association Between Influenza Vaccination and The Risk of Acute Kidney Injury Among Older People in Korea: Self-Controlled Case Series Analysis

Sunday, August 28, 2022

8:00 AM – 1:45 PM CEST

Location: Hall C

Publication Number: 1309

Presenting Author(s)

Haerin Cho
– Ewha university, Seodaemun-gu, South Korea

Co-Author(s)

EUNSUN LIM
– Seodaemun-gu, South Korea
Heejin Kim
– Ewha Womans University, Seodaemungu, South Korea
Na-Young Jeong
– Ewha Womans University, Seodaemungu, Gyeonggido, South Korea
Nam-Kyong Choi
– Department of Health Convergence, College of Science & Industry Convergence, Ewha Womans University, Seoul, Republic of Korea, Republic of Korea

Background: The elderly over 65 are eligible for national influenza vaccination in Korea. After influenza vaccination, there have been several case reports of renal complications, including acute kidney injury (AKI). However, the evidence of the association between influenza vaccine and AKI is insufficient.

Objectives: To investigate whether influenza vaccination is associated with AKI occurrence among Korean elderly in the 2017/2018 season.

Methods: We used the database of vaccination registration data from the Korea Disease Control and Prevention Agency linked with the claims data from the National Health Insurance Service. We defined the 2017/2018 flu season from September 1st, 2017, to April 30th, 2018. People who were hospitalized with AKI (ICD-10: N17) for the first time following vaccination were included in this study. The study subjects were restricted to those who received one influenza vaccine in the 2017/2018 season and those who were 65 years of age or older at the date of vaccination. Patients with a history of kidney disease, including kidney transplantation and dialysis prior to vaccination, were excluded. We performed a self-controlled case series study in which the risk interval was 1 to 14 days after vaccination, and the observation period was 180 days after vaccination. We used conditional Poisson regression to compare incidence in the risk and control interval. As sensitivity analyses, we analyzed with different risk interval (days 1-28) and the same observation period.

Results: A total of 4,717 AKI events were identified during the observation period. The number of events was 269 during the risk interval. During the risk and control interval, the incidence rates were 1.50 and 2.92 per 100,000 person-year, respectively. The incidence rate ratio (IRR) for AKI was 0.51 (95% confidence interval [CI]=0.45-0.58). Sensitivity analyses showed similar results (IRR=0.52, 95% CI=0.48-0.58).

Conclusions: In this study, influenza vaccination is associated with a lower risk of AKI in the elderly over-aged 65. This finding is consistent with a previous study. Further studies are needed to determine whether this finding is due to the vaccine effectiveness or bias resulting from the underlying health conditions of those vaccinated.