Infective Endocarditis-Related Stroke Rising, More Associated With IV Drug Use

From 2005 to 2015, rates of infective endocarditis-related stroke (IERS) in the United States increased with affected patients more likely to be intravenous (IV) drug users, according to study findings published in Neurology.

Between 20% and 40% of patients with infective endocarditis will have an ischemic stroke event. In recent years, there has been an increase in hospitalizations due to drug-related IERS. As trends appear to be evolving, this study was designed to evaluate recent trends in the IERS patient population.

Researchers from University of Cincinnati Medical Center in the US sourced data from the Greater Cincinnati/Northern Kentucky Stroke Study (GCNKSS) which collected data every 5 years on inpatient strokes in a 5-county region. Demographics and trends in patients (N=8258) with stroke were evaluated between 2005 and 2015.

In 2005, 2010, and 2015, there were 2610, 2715, and 2933 patients with stroke, among whom 12, 17, and 25 had infective endocarditis, respectively.

Over time, fewer patients with IERS had hypertension (P =.0005) and more were IV drug users (P =.02).

The IERS cohort presented with ischemic stroke (81.5%), intraparenchymal hemorrhage (14.8%), or subarachnoid hemorrhage (3.7%). A fifth of patients (20.4%) were known to have active infective endocarditis at stroke recognition.

The most common bacteria identified at blood culture were Enterococcus and methicillin-sensitive or -resistant staphylococcus aureus. The most common vegetations were located on the mitral or aortic valves.

Rates of IERS were increasing over time from 1.31 per 100,000 in 2005 to 1.66 per 100,000 in 2010 and 2.41 per 100,000 in 2015. Conversely rates of non-endocarditis stroke decreased slightly over time from 280 per 100,000 in 2005 to 274 per 100,000 in 2015.

Overall, compared with the entire stroke population, patients who had endocarditis had higher modified Rankin Scale (mRS) scores at 30 days (median, 3 vs 4 points) and 30-day (15.6% vs 33.3%) and 90-day (20.5% vs 48.2%) all-cause mortality rates, respectively.

Stratified by IV drug use (n=16) and no drug use (n=38) in IERS events, patients who were drug users were younger, fewer were women, had atrial fibrillation, other infections in the previous 2 weeks, more presented at the emergency department, were septic at presentation, and they had lower mRS scores at 30 days (all P ≤.04) compared with non-drug users.

In the non-IERS cohort, there were more Black and male individuals and more presentation of hypertension, diabetes, atrial fibrillation, and perioperative stroke.

The major limitation of this study was the small IERS event rate.

This study found that over time, IERS rates have been increasing among a population that is more likely to be IV drug users. The researchers emphasized, “The impact of the opioid epidemic is reflected in the transforming phenotype of IERS.”

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.