Hospitalizations for drug use-associated infective endocarditis (DUA-IE) increased 12-fold in North Carolina in one decade, according to a new study, and nearly half of all IE valve surgeries from late 2016 through mid-2017 were performed in patients with DUA-IE.
The findings mirror previous studies which concluded that DUA-IE is “a growing healthcare crisis” occurring in conjunction with the opioid epidemic and a rise in injection drug use. Opioids were the most commonly implicated drug in hospitalizations for DUA-IE among North Carolina adults from July 2007 through June 2017, appearing in 62 percent of cases.
“The swell of patients with DUA-IE is reshaping the scope, type, and financing of health care resources needed to effectively treat IE,” lead author Asher J. Schranz, MD, with the University of North Carolina, and colleagues reported in the Annals of Internal Medicine.
The study utilized a statewide discharge database to identify 22,825 IE hospitalizations over the 10-year span, including 11 percent which were associated with drug use. At the population level, the incidence of DUA-IE hospitalizations jumped from 0.92 to 10.95 per 100,000 adults during the study period, a 12-fold increase. Hospitalizations with valve surgery in that population increased from 0.10 to 1.38 per 100,000 people, encompassing 42 percent of all IE valve surgeries in the final year of the study.
Meanwhile, the number of IE cases not linked to drug use remained relatively stable, and those hospitalizations were a median 10 days shorter with median costs about $52,000 lower.
“Although our study focuses on one state, findings in North Carolina may reflect nationwide trends,” the authors noted. “Past-year misuse of pain relievers or heroin and the overdose death rate in the state align closely with U.S. averages.”
Compared to the rest of the IE population, drug users were significantly younger (median 35 versus 67 years old) and were more often white (81 percent versus 61 percent). They were also more likely to be on Medicaid, self-insured or uninsured, whereas other endocarditis patients were more commonly on Medicare or private insurance.
Another discordant finding was the rates of discharge against medical advice (DAMA), which occurred in 13 percent of DUA-IE hospitalizations and just 1 percent of other IE cases. Schranz et al. noted DAMA is most common among patients with drug and alcohol abuse histories, and said the underlying substance use disorder should be treated as the “root cause” of IE.
“Detoxification without pharmacotherapy for opioid use disorder is ineffective, with estimated relapse rates ranging from 60% to 81% within a year or less, suggesting that those who do not receive treatment for opioid use disorder are likely to start using opioids again after discharge, putting them at risk for reinfection if they inject drugs,” the researchers wrote.
In a related editorial, Alysse G. Wurcel, MD, MS, agreed that better use of behavioral counseling could improve the rates of DAMA among DUA-IE patients.
“Not only are DAMAs stressful for patients and clinicians, they also may lead to abrupt discontinuation of treatment, disease progression, and death,” wrote Wurcel, with Tufts Medical Center and Tufts University in Boston. “New data are available that support fewer DAMAs and fewer readmissions among patients hospitalized for infections who receive addiction medicine counseling. Clinicians trained in addiction medicine are key partners in treating DUA-IE and need to be involved soon after infected patients are admitted.”
Schranz et al. speculated the longer hospital stays among drug users in their analysis was related to the perception that they can’t be trusted to administer their own IV antibiotics in an unsupervised setting. But evidence contends they can safely follow an outpatient parenteral antibiotic therapy (OPAT) regimen, the authors said, writing “expanding OPAT eligibility among selected candidates may help offset long hospital stays for drug use-associated infections.”
The authors noted several factors may have affected their detection of DUA-IE cases throughout the study period. They used codes for hepatitis C virus infections to identify 18 percent of their DUA-IE hospitalizations because of hepatitis C’s link to IV drug use, but acknowledged this may have led to an overestimation of DUA-IE cases. However, the database didn’t include Veterans Affairs and military hospitals, which likely led to an underreporting of the true incidence of IE in North Carolina.