WASHINGTON, D.C.—Statin therapy may help solid-organ transplant (SOT) patients reduce their risk of death from bloodstream infections (BSIs), according to researchers.
“We were not surprised by our findings because similar [effects from statins] were previously observed in nontransplant populations,” said lead investigator Jennifer Hsu, MD, an infectious disease fellow at the University of Wisconsin in Madison. She presented her group’s findings here at a joint meeting of the Interscience Conference on Antimicrobial Agents and Chemotherapy and the Infectious Diseases Society of America.
BSIs are a major cause of morbidity and mortality among the more than 45,000 patients who receive abdominal SOTs annually in the United States. Meanwhile, knowledge of the factors influencing outcomes of BSIs is limited.
Dr. Hsu and her colleagues retrospectively studied all recipients of kidney, pancreas, and/or liver transplants diagnosed with at least one episode of BSI over an 11-year period at a single institution. The researchers identified 604 episodes of BSI in 311 SOT recipients. The cohort comprised 188 men (60%) and 123 women (40%), mean age 51 years (range 18-77 years).
The group included 127 kidney transplant recipients (41%), 104 liver transplant recipients (33%), and 33 kidney-pancreas transplant recipients (10%). The other 47 patients were those who received simultaneous liver-kidney transplants or other combinations of sequential transplants. Statin use was documented in 80 patients (25%). Among the 311 recipients, 54% had a single episode of BSI, and 25% had two episodes; the mean Acute Physiology and Chronic Health Evaluation (APACHE) score was 17.3.
The investigators concluded that BSI in SOT recipients is associated with high mortality, with lack of appropriate antibiotic use linked to an increased risk of death (odds ratio [OR] 4.65). Statin therapy was associated with a decreased risk of death (OR 0.18).
The source of BSI was abdominal in 97 patients (31.8%), urinary in 78 patients (25.5%), and urinary with line-in in 61 patients (20%). Gram-negative organisms were identified in 118 patients (35%) and gram-positive orgranisms in 145 patients (43%). In the remaining 22% of patients, the infections were polymicrobial or were caused by anaerobes and fungi. Forty-four patients (14%) died within 15 days of BSI.
The mechanism by which statin therapy confers protection in SOT recipients is unclear, but several have been proposed, Dr. Hsu said. These include reduction of cytokine release, and possible modulation of the immune system, she said. “Statins may have a role in modulating the immune system, but we don’t have the data yet to say that for sure.”