Assessing influenza vaccination coverage and predictors in persons living with HIV/AIDS in Louisiana, June 2002-June 2013.

Background: Despite the burden of disease and increased risk of influenza-associated morbidity and mortality among PLWHA, influenza vaccination has been understudied in this population. Methods: We built an 11-year cohort of HIV-infected adults from medical records of PLWHA seeking care within the Louisiana State University medical system from June 2002-June 2013. Influenza vaccination uptake among PLWHA was calculated overall and for each medical facility for each influenza season. Linear regression was used to assess influenza vaccination uptake over time, both overall and by facility. Data were restricted to the final influenza season (2012-13) to assess predictors of PLWHA vaccination. Individuals were nested within medical facilities in order to assess the amount of variability in influenza vaccination rates across medical facilities. Results: Influenza vaccination uptake among PLWHA increased over the study period (p < 0.01). The overall proportion of PLWHA vaccinated during the 2012-13 influenza season was 33.7%. 37.9% of the variability in the model occurred at the facility-level. Conclusions: Although there was an increase in influenza vaccination within the PLWHA cohort over the course of the study, vaccination rates remained low overall. Special efforts must be made to increase vaccination uptake among PLWHA, with particular focus on those within the population who are likely to be at highest risk. The substantial variability at the facility-level indicates that there are unmeasured facility-level factors that contribute significantly to PLWHA vaccination.