Effect of influenza vaccination on disease progression among HIV-infected persons

Objective: To describe the effect of influenza vaccination on long-term cha nge in CD4 count and HIV RNA level, and on progression to AIDS or death. Design and setting: A longitudinal medical record review set in 113 medical clinics in 10 United States cities. Patients: A total of 36 050 HIV-infected persons aged greater than or equal to 13 years in care for HIV infection. Main outcome measures: Change in CD4 count and HIV RNA level at follow-up ( 3-12 months after vaccination); hazard ratios (HR) for association of influ enza vaccine with progression from baseline CD4 or HIV RNA level to AIDS an d to death. Results: The median CD4 count among all persons decreased 28 cells/year dur ing follow-up, with no difference in change in CD4 count between the 8007 ( 40%) vaccinated (median = 6 months, vaccine to follow-up CD4 count) and the 11 794 unvaccinated persons. In a viral load subanalysis, median HIV RNA l evel decreased 90 copies/ml per year among all persons during follow-up; de creases were not different between vaccinated and unvaccinated persons. (me dian = 7 months, vaccine to follow-up HIV RNA level determination). Influen za vaccination was weakly associated with decreased risk of progression to clinical AIDS [HR 0.93; 95% confidence interval (CI), 0.87-0.99], but not a ssociated with time to death (HR, 0.97; CI, 0.93-1.01). Conclusions: No negative long-term effect of influenza vaccination on CD4 c ounts, HIV RNA levels, or progression to AIDS or death was found in this HI V-infected population. These data suggest that physicians should not withho ld influenza vaccine because of concerns about long-term detrimental effect s of increased viral replication. (C) 2000 Lippincott Williams & Wilkins.