COVID-19 patients with substance use disorders, especially those who are using drugs that impair the cardiovascular and respiratory systems, are at an increased risk for adverse outcomes, the researchers found in a double-cohort study of 11,124 adults diagnosed with COVID-19 that was published in Psychiatric Services in Advance.
The researchers obtained data for the study using the TriNetX Research Network platform, a global federated network of electronic medical record data from 35 health care organizations, typically large academic health centers and their affiliates, that were designed to facilitate research related to COVID-19. Adult patients who were diagnosed as having a COVID-19 infection between February 20 and June 30, 2020 were selected.
The researchers excluded patients who did not have at least 1 health care visit in the 12 months before the diagnosis and patients who had diagnosis codes indicating other specified viral infection or suspected exposure to other biologic agents during the same timeframe. Diagnosis of substance use disorder was determined by using algorithms based on ICD-10-Clinical Modification codes. The researchers examined demographic characteristics and the following comorbid conditions: diabetes, hypertension, chronic obstructive pulmonary disease, ischemic heart disease, obesity, and cerebrovascular disease.
The researchers identified two matched cohorts within TriNetX: 1 of 5562 patients with a substance use disorder matched on demographic characteristics, obesity and diabetes and another of 5450 patients matched on demographics, diabetes, obesity, hypertension, COPD, ischemic heart disease and cerebrovascular disease. The researchers excluded hypertension, COPD, ischemic heart disease and cerebrovascular disease from the primary propensity score (PS)-matched models because they were possible mechanistic pathways between substance use disorder and adverse COVID-19 outcomes.
The researchers examined the outcomes of hospitalization, ventilator use, and mortality that occurred within 21 days of COVID-19 diagnosis in the substance use disorder versus non-substance use disorder cohorts.
They found in the unmatched analysis that substance use disorder was associated with an increased risk of hospitalization (32.5% versus 17.4%, odds ratio [OR]=2.29, 95% confidence interval [CI]=2.16–2.44), ventilator use (6.0% versus 3.1%, OR=2.02, 95% CI=1.79–2.28) and mortality (4.9% versus 2.8%, OR=1.81, 95% CI=1.58–2.07).
In the PS-matched cohort that was matched on demographic characteristics, diabetes, and obesity, substance use disorder was associated with an increased risk of hospitalization (1808 patients or 32.5% versus 1152 patients or 20.7%, OR=1.84, 95% CI=1.69–2.01), ventilator use (334 patients or 6.0% versus 235 patients or 4.2%, OR=1.45, 95% CI=1.22–1.72), and mortality (270 patients or 4.9% versus 210 patients or 3.8%, OR=1.30, 95% CI=1.08–1.56).
The final PS-matched cohort included 4 additional comorbid conditions (hypertension, COPD, ischemic heart disease, and cerebrovascular disease), that were potentially mechanistic pathways between substance use disorder and adverse outcomes. In this model, substance use disorder was still associated with an increased risk of hospitalization (1682 patients or 30.9% versus 1231 patients or 22.6%, OR=1.53, 95% CI=1.40–1.65) and ventilator use (294 patients or 5.4% versus 233 patients 4.3%, OR=1.28, 95% CI=1.07–1.52) but not with mortality (257 patients or 4.7% versus 256 patients or 4.7%, OR=1.00, 95% CI=0.84–1.20).
Limitations of the study included the reliance of data on ICD-10-CM codes which may not be accurate. Also, the reliance on electronic health records data made it impossible to assess potential confounding factors and markers of adverse socioeconomic disadvantages.
“Our findings suggest that among patients with COVID-19, those with a comorbid substance use disorder have an increased risk of adverse outcomes,” the authors said. “The attenuation of the risk for mortality in the final model may reflect an important mediating role of drug-related respiratory and cardiovascular disease.”
Disclosure: One study author declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Baillargeon, J, Polychronopoulou, E, Kuo YF, Raji, M. The impact of substance use disorder on COVID-19 outcomes. Psychiatric Serv. Published online November 3, 2020. doi:10.1176/appi.ps.202000534