The Centers for Disease Control and Prevention (CDC) recommends at least annual HIV and HCV testing for persons who inject drugs (PWID). This paper from the CDC assessed the prevalence of testing for these infections among PWID – a population that remains at high-risk for blood-borne infections despite broader availability of syringe and needle exchange programs. The study used a national health insurance database that included over 230 million persons covered under 371 different commercial plans. The subjects assessed were patients aged 15–49 years who had ≥1 medical diagnosis (ICD-9, ICD-10, or CPT coded), procedure, or medication dispensed indicative of injection drug use (IDU) from 2010 to 2016. Patients were most frequently identified as being at-risk through infections related to IDU including abscesses, cellulitis, osteomyelitis, or endocarditis. In addition, 32% had a documented diagnosis of drug abuse or drug-dependence. Regarding the clinical encounters, the majority of patients received care at a general medical clinic (46%) hospital (33%) and ED/urgent care (14%). Specific outcomes were HIV and HCV testing within 12 months of the first clinical counter related to IDU. The study then estimated the percentage of patients tested for HIV or HCV within one year of the index encounter by using multivariate logistic regression models to assess demographic and clinical factors associated with testing. There were 844,242 individuals who had a clinical encounter indicative of IDU during 2010-2016 but only 8.6% were tested for HIV and only 7.7% for HCV. Missed opportunities independently associated with NOT testing for HIV or HCV included being male, living in a rural setting, or getting medical services for skin infections or endocarditis. The authors note that despite a growing national awareness of drug use related to the U.S. opioid epidemic, interventions are needed to improve HIV and HCV testing rates in at-risk populations.

Author’s Commentary:

This is rather discouraging data as more than 90% of persons with medical risks associated with IDU or substance use did NOT have HIV or HCV testing. Despite the presumed access to medical care and laboratory testing covered by private health insurance, these rates are extremely low. It is not clear from this study if some of the patients underwent HIV/HCV screening in alternative outpatient settings. These data are reminiscent of pre-2006 when our HIV testing focused only on “at risk” populations, which did poorly in getting people tested and diagnosed. This confirmed the need for routine, opt-out testing. With about 15% of persons with HIV undiagnosed and a greater percentage with HCV undiagnosed, continued educational efforts and removal of barriers for testing remain critically important. Perhaps also a reminder to our hospitalist colleagues to ramp up their in-patient HIV/HCV testing.