Almost one-fifth of patients with opioid use disorder (OUD) in a large health care system died during a four-year follow-up period, according to a study published in the Journal of Addiction Medicine. The results suggest high rates of serious illness and death among patients with OUD in general medical care settings––much higher than for those in addiction specialty clinics, according to lead investigator Yih-Ing Hser, PhD, of the University of California–Los Angeles.
Using electronic health records from their university health care system, Hser and colleagues identified 2,576 adults with OUD. The patients’ average age was 41 years at the first OUD diagnosis. They all had high rates of physical and mental-health disorders and other types of substance-use disorder.
After four years of follow-up, 465 (18%) of the patients had died. This mortality rate was more than 10 times higher than that of the general population, adjusted for age and sex.
Approximately 19% of deaths were due to causes directly related to OUD and drug overdose. But most patients died of other causes, especially cardiovascular disease, cancer, and infectious diseases.
The most common infection-related cause of death was hepatitis C virus (HCV) infection. Because of their injection drug use and other risky behaviors, people with OUD are at high risk for HCV infection. The risk of death for OUD patients with HCV infection was twice as high as that for patients with OUD alone. Patients with alcohol use disorder also had increased mortality.
The risk of death from cardiovascular disease was higher for patients with tobacco use disorder. Mortality from cancer was increased for patients with HCV infection, while death from liver disease was more common for patients with HCV infection and alcohol use disorder.
Previous studies have found a high risk of death among people with OUD, most commonly from drug overdose. However, most of those studies had focused on patients being treated in addiction specialty clinics or programs. One recent study found that the risk of death among patients receiving treatment for OUD was four times higher than in the general population, increasing to six times higher after they were out of treatment.
The new findings suggest a much higher risk of death for patients with OUD in general medical care. Hser and coauthors note that the patients identified in their health care network were older when first diagnosed with OUD, and had high rates of other physical health disorders.
The high mortality among their subjects may reflect issues with identifying and addressing OUD in the health care system, the authors suggest. “It is likely that patients seen in this health system became progressively sicker, as their OUD problem was not identified until very late in its course, and after physical health complications had already ensued,” they write.
Within its limitations, the study may have important implications for health care amid the ongoing opioid epidemic. In the United States, health care providers outside of specialty substance-use disorders treatment settings have not traditionally been adequately equipped to identify and address patients with addictions, the researchers note.
They point out that their findings do not imply that addiction treatment has worse outcomes in general health settings; rather, the higher mortality likely resulted from the patients not receiving adequate care. The authors believe that earlier intervention might be able to reduce some of the high rates of complications and death among patients with OUD in general medical care.
Source: EurekAlert; April 24, 2017.