Early postoperative mortality may not differ between infective endocarditis caused by injection drug use (IDU) and non-IDU causes, despite different preoperative clinical characteristics, according to a study published in Clinical Infectious Diseases.
Along with congenital and acquired valve abnormalities, IDU is a risk factor for infective endocarditis, which contributes to the high rate of morbidity and mortality associated with the infection. The current opioid epidemic has rapidly increased the burden for healthcare use for patients with IDU infective endocarditis; IDU has been associated with roughly 50% of cases of infective endocarditis. Between 2005 and 2015, the American Heart Association shifted its guidelines toward earlier surgical intervention for infective endocarditis and cautioned that there may be concern for increased risk for short- and long-term complications after valve surgery in people who inject drugs.
Supporting evidence for increased risk for postoperative mortality in people with infective endocarditis from causes other than IDU is limited and conflicting. Clarity on the effect of etiology of infective endocarditis, whether it is related or unrelated to IDU, on postoperative mortality after valve surgery is crucial. Therefore, this study compared short-term postoperative mortality in patients with infective endocarditis as a result of IDU vs non-IDU through systemic review and meta-analysis.
A total of 13 studies with 1593 patients (21.4% IDU-associated infective endocarditis) were included from publication databases up to September 2017. These studies included randomized controlled trials, prospective cohorts, and retrospective cohorts that reported on 30-day mortality or in-hospital/operative mortality after valve surgery that included compared outcomes between infective endocarditis as a result of IDU with non-IDU causes.
Meta-analysis results showed that patients with infective endocarditis who use injectable drugs more frequently had a tricuspid valve infection, staphylococcal infection, and heart failure before surgery. In-hospital mortality as a postsurgical outcome was evaluated in 6 of the included studies, and meta-analysis revealed no statistically significant difference between the 2 groups (risk ratio, 0.88). Further, all 13 studies evaluated early mortality, defined as either in-hospital or within 30 days, as a postsurgical outcome; meta-analysis revealed no statistically significant difference in early mortality between patients with infective endocarditis as a result of IDU and those with non-IDU etiology (risk ratio, 0.82).
Overall, the study authors concluded that, “Future research on long-term outcomes following valve replacement is needed to identify opportunities for improved healthcare delivery with IDU [infective endocarditis].”
Hall R, Shaughnessy M, Boll G, Warner K, Boucher HW, Bannuru RR, Wurcel AG. Drug-use and post-operative mortality following valve surgery for infective endocarditis: a systemic review and meta-analysis [published online December 22, 2018]. Clin Infect Dis. 2019. doi: 10.1093/cid/ciy1064/5257358