Association between discharges against medical advice and readmission in patients treated for drug injection-related skin and soft tissue infections

Background: The prevalence of injection drug use (IDU)-related skin and soft tissue infections (SSTI) in Philadelphia has been steadily increasing since 2013. Patients seeking treatment for these infections are more likely to be discharged against medical advice (AMA), increasing the likelihood that they will end antibiotic treatment prematurely and require additional medical interventions.

Methods: The research team performed a nested case-control study using the Pennsylvania Health Care Cost Containment Council database for Philadelphia residents hospitalized for SSTI and substance use-related diagnoses between 2013 and 2018. The primary outcome was readmission in the same or following quarter. The study examined the impact of discharge AMA on readmission along with clinical characteristics including diagnoses for anxiety, bipolar disorder, depression, schizophrenia, diabetes, and polydrug use.

Results: There were 8265 hospitalizations for IDU-related SSTI and 316 (6%) were readmitted to the hospital at least once in the same or following quarter. In total, 23.4% of cases and 13% of controls left AMA. In the final multivariable regression model, AMA discharge (AOR 2.04, 95% CI 1.46-2.86), anxiety (AOR 1.44, 95% CI 1.01-2.05), diabetes (AOR 2.02, 95% CI 1.46-2.81), and polydrug use (AOR 2.11, 95% CI 1.52-2.92) were associated with higher odds of readmission.

Conclusions: Our study demonstrates that readmissions for IDU-related SSTI are associated with recent discharge AMA. As IDU-related SSTI and polydrug use continue to rise, premature antibiotic treatment completion will impact more people, leading to worse health outcomes and additional strain on the health care system.