Abstract
INTRODUCTION: Influenza infections contribute to excess healthcare utilization, morbidity, and mortality in individuals with glomerular disease (GD); however, influenza vaccination may not yield protective immune responses in this high-risk patient population. The objective of the present study was to describe influenza vaccine administration from 2010 to 2019 and explore the effectiveness of influenza vaccination in patients with GD. METHODS: We conducted an observational cohort study using healthcare claims for seasonal influenza vaccination (exposure) as well as influenza and influenza-like illness (outcomes) from commercially insured children and adults <65 years of age with primary GD in the Merative MarketScan Research Databases. Propensity score-weighted cox proportional hazards models and ratio-of-hazard ratios (RHR) analyses were used to compare influenza infection risk in years where seasonal influenza vaccines matched or mismatched circulating viral strains. RESULTS: The mean proportion of individuals vaccinated per season was 23% (range 19%-24%). In pooled analyses comparing matched to mismatched seasons, vaccination was minimally protective for both influenza (RHR 0.86, 95% confidence interval [CI]: 0.52-1.41) and influenza-like illness (RHR 0.86, 95% CI 0.59-1.24), though estimates were limited by sample size. CONCLUSION: Rates of influenza vaccination are suboptimal among patients with GD. Protection from influenza after vaccination may be poor, leading to excess infection-related morbidity in this vulnerable population.