Invasive Pneumococcal Disease Among HIV-Infected and HIV-Uninfected Adults in a Large Integrated Healthcare System.

Abstract

It is unclear whether HIV-infected individuals remain at higher risk of invasive pneumococcal disease (IPD) compared with HIV-uninfected individuals. We conducted a cohort study of HIV-infected and demographically matched HIV-uninfected adults within Kaiser Permanente Northern California during the period 1996-2011. We used Poisson models to obtain rate ratios (RRs) for incident IPD associated with HIV infection and other risk factors. Among 13,079 HIV-infected and 137,643 HIV-uninfected adults, the IPD rate per 100,000 person-years was 160 (n = 109 events) for HIV-infected and 8 (n = 75 events) for HIV-uninfected subjects, with an adjusted RR of 13.0 [95% confidence interval (CI): 9.1-18.7]. For HIV-infected individuals, IPD incidence per 100,000 person-years decreased by 71% during study follow-up, from 305 in 1996-1999 to 88 in 2010-2011 (p < 0.001), with an adjusted RR of 6.6 (95% CI: 2.7-16.1) compared with HIV-uninfected subjects in 2010-2011. Risk factors for IPD among HIV-infected individuals included black compared with white race/ethnicity, smoking, cancer, and higher HIV RNA levels. The 23-valent pneumococcal polysaccharide vaccination was not associated with a reduced risk of IPD in HIV-infected or HIV-uninfected individuals. Among HIV-infected IPD cases, the most common serotype was 19A (33%), and 59% of serotypes were covered by the 13-valent pneumococcal conjugate vaccine (PCV13). Despite a dramatic decline in IPD incidence for HIV-infected adults since 1996, IPD rates were nearly sevenfold higher compared with HIV-uninfected adults in recent years, even after adjustment for risk factors. Timely antiretroviral therapy initiation, risk reduction strategies, and recent guidelines recommending PCV13 use may further reduce IPD incidence among HIV patients.