The likelihood of bacterial blood infections among patients with HIV has risen slightly in recent years
Research Activities, August 2011, No. 372
Bacteremia is the 10th leading cause of death among persons 45 years and older, with HIV-infected patients at greater risk than HIV-negative patients. However, the likelihood of bacteremia has risen slightly in this group in recent years. Blacks and intravenous drug users (IDUs) with HIV are more likely than other patients with HIV to develop bacterial blood infections (bacteremia), concludes a new study. The study followed 39,318 HIV-infected patients, 57 percent of whom were on highly active antiretroviral therapy (HAART) during the enrollment year, for up to 9 years.
John A. Fleishman, Ph.D., of the Agency for Healthcare Research, and colleagues found that the incidence of bacteremia was 13.8 events per 1,000 patient-years (PY) over the 9-year period. This rate was substantially lower than that seen in studies conducted at single clinical sites early in the era of HAART. However, the incidence per 1,000 PY in the new study declined from 15.1 in 2000 to a low of 10.7 in 2002, only to rebound to 15.0 in 2004, then declined slightly over the rest of the study period, but still staying at 13.4 in 2008.
Factors associated with significantly higher odds of bacteremia included black race (45 percent higher odds than white patients) and past IDU (65 percent higher odds than for men who had sex with men). Receipt of HAART did not appear to be directly protective against bacteremia. But patients with stronger immune systems (higher CD4 lymphocyte counts) had progressively reduced bacteremia risk, as did patients with progressively lower HIV-1 RNA copies per mL of blood (lower HIV load).
The researchers could not conclusively link bacteremia with Staphylococcus aureus. However, supplementary data from one of the participating sites found that 38 percent of 184 "bacteremia not otherwise specified" cases were due to S. aureus, and 42 percent of these were methicillin-resistant S. aureus (MRSA). The findings were based on analysis of data from the HIV Research Network, a consortium of sites that provide primary care and subspecialty care to HIV-infected patients in 14 cities in the United States. The study was funded in part by the Agency for Healthcare Research and Quality (Contract No. 290-01-0012).
More details are in "Incidence of and risk factors for bacteraemia in HIV-infected adults in the era of highly active antiretroviral therapy," by Baligh Ramzi Yehia, M.D., Dr. Fleishman, Lucy Wilson, Sc.M., and others for the HIV Research Network, in the March 2011 HIV Medicine [Epub ahead of print]. Reprints (AHRQ Publication No. 11-R041) are available from the AHRQ Publications Clearinghouse.