By Marie Rosenthal, MS
The incidence of infective endocarditis among cocaine and opioids users increased from 2011 to 2022, and this risk doubled during the COVID-19 pandemic, according to a recent study.
Among patients with either cocaine or opioid use disorder, those who were diagnosed with COVID-19 faced a three to eight times higher risk for a new endocarditis diagnosis and hospitalization than those without COVID-19 (Mol Psychiatry 2022 Dec 13. doi:10.1038/s41380-022-01903-1).
Nora D. Volkow, MD, the director of the National Institute on Drug Abuse (NIDA), and a team of scientists at Case Western Reserve University, in Cleveland, analyzed de-identified electronic health record data of more than 109 million unique patients collected from January 2011 through August 2022. Patient data were derived from 77 hospitals across the United States, covering diverse geographic locations, age groups, racial and ethnic groups, income levels and insurance types.
They found that, in 2011, there were four cases of endocarditis per day for every 1 million people with opioid use disorder (OUD). In 2022, this rate increased to 30 cases per day per 1 million people with OUD. For people with cocaine use disorder, cases increased from five per 1 million people with cocaine use disorder in 2011 to 23 cases in 2022.
A clinical diagnosis of COVID-19 more than doubled the risk for a new diagnosis of endocarditis in patients with either cocaine use disorder or OUD, they said. Among these patients, the risk for hospitalization within 180 days following a diagnosis of endocarditis was about 68% in patients with COVID-19, compared with 59% in those without the disease. Moreover, the mortality risk within 180 days following a new diagnosis of endocarditis was 9% in those with COVID-19, compared with 8% in patients without the disease.
“As the scientific understanding of long COVID develops, we can now include endocarditis as one long-term effect on key organ systems for people who inject drugs,” said Rong Xu, PhD, a professor of biomedical informatics at Case Western University and co-corresponding author of this study. “It’s critical that we continue to monitor long-term, broad impacts of COVID-19 on people who use drugs.”
C. Michael White, PharmD, FCP, FCCP, said it is not surprising that endocarditis is increasing during COVID-19. “With the lockdowns of recreational areas, the loss of jobs, reduced contact with support people or loved ones, and the fear and stress that ensued the early phase of the pandemic, the utilization of illicit substances of abuse rose, which could increase the risk for endocarditis by itself.
“In addition, COVID-19 infections can cause inflammatory responses and might have enhanced the endocardial inflammation that derange the heart valves and make them more prone to become infected,” said Dr. White, the department head and Distinguished Professor of Pharmacy Practice at the University of Connecticut School of Pharmacy, in Storrs. Dr. White was not part of the Molecular Psychiatry study, but is an expert in cardiology.
Minority Risk
The findings also showed that Black and Hispanic people faced a lower risk for COVID-19–associated endocarditis than non-Hispanic white people. The researchers noted this is consistent with a higher prevalence of injection drug use in non-Hispanic white populations, compared with Black or Hispanic populations.
One in 10 hospitalizations for endocarditis is associated with injection drug use, and these numbers continue to increase, they said. Inadequate access to sterile injection equipment is common among injection drug users and dramatically increases the risk for infection in people who inject drugs, such as cocaine, methamphetamine and opioids (Clin Infect Dis 2000;30[2]:374-379).
“These put patients at risk for bacteremia, which is the prime cause of infectious endocarditis, but the incidence and frequency of endocarditis per bacteremic exposure seems higher in intravenous substance use disorder.
It is believed that chronic endocardial inflammation is a prime reason for this,” Dr. White explained.
And the drugs themselves are cut with so many impurities that “people are injecting a cocktail of different chemicals, including banned or non–FDA-approved substances, and small particulates in addition to their intended substance of abuse that can initiate inflammatory states,” which increases the risk even more, added Dr. White, who studied the substances added to illicit drugs (J Clin Pharmacol 2021;61[suppl2]:S129-S141).
Actual Practice
Thomas M. File Jr., MD, MSc, FIDSA, the chair of the Infectious Disease Division and co-director of the Antimicrobial Stewardship Program, Summa Health, Akron, Ohio, said his hospital has been treating an increasing number of cases of endocarditis, and many are related to COVID-19, particularly among patients with OUD. Dr. File was also not part of the NIDA study. (For more on the intersection of infectious diseases and the opioid epidemic, click here.)
“I think this is the combination of three significant medical illnesses,” said Dr. File, who is also a member of the Infectious Disease Special Edition editorial advisory board. “One, COVID 19. Number two is opioid use disorder, which is a significant one in and of itself. And then three, endocarditis, which obviously is a significant infection.
“We are seeing more of that. And I think there may be several reasons for this. I think obviously during the pandemic, in many cases we’ve seen a diversion of our healthcare from standard health maintenance mainly because of staffing and other issues. Because of the need to address and respond to COVID-19, some of these other issues [like OUD] may not be receiving as much of a priority as they should,” said Dr. File, who is also a professor of internal medicine, and the master teacher chair of the infectious disease section at Northeast Ohio Medical University, in Rootstown.
In addition to a lack of access to care because of the pandemic, those with OUD face stigma that is important to overcome. His institution manages patients with a very comprehensive addiction medicine program.
“When patients come in with infections such as endocarditis, it’s going to be a multispecialty assessment with infection diseases, addiction medicine and then obviously other providers for cardiology, cardiovascular surgery, etc., etc.
“This is a significant issue,” he added. In addition to the multispecialty approach, patients may need medications to help them overcome their addiction, such as buprenorphine and buprenorphine-naloxone.
Dr. Volkow said services such as syringe service programs also can help people avoid infection from reused or shared injection equipment, and could help lower this risk.
