Abstract 313: Investigation of Substance Use in the Bridge Population

Background: Alcohol and drug dependence has been linked to increased readmissions and ED visits in some populations. This study investigated the impact of different substance use (SU) on outcomes (ED visit, readmission, death) among hospitalized cardiac patients (pts).

Methods: Data on all pts referred to the BRIDGE cardiac transitional care clinic from 2008-2017 were collected. Chart review was conducted on a random selection of pts with a history of SU (n=152) to determine the type of substance used: alcohol, tobacco, illicit substances (i.e. cocaine, narcotics, marijuana) (study conducted prior to Michigan’s legalization of marijuana), or multiple substances. Demographics and outcomes at 30 and 180 days were compared between SU groups.

Results: Of 3536 pts, 305 (8.6%) had a history of SU. Compared to those without SU, SU pts were younger (57.3±13.2 v 66.7±14.5 years, p<0.001), male (72.8% v 62.1%, p<0.001), single (62.5% v 38.0%, p<0.001), non-white (21.9% v 15.6%, p=0.005), less likely to attend their BRIDGE appointment (35.7% v 28.3%, p=0.012), had lower Charlson comorbidity scores (CCS) (3.7 v 4.9, p<0.001), and were more likely to visit the ED within 180 days of discharge (44.4% v 38.1%, p=0.033). Of 152 randomly selected SU pts, 57 (37.5%) used alcohol, 20 (13.2%) tobacco, 28 (18.4%) illicit, and 47 (30.9%) multiple substances. Illicit substance users were more likely to be from low SES communities. Despite older age and higher CCS than the other SU groups, alcohol users had fewer 180 day ED visits (p=0.007) and 180 day readmissions (p=0.024) than illicit substance users, as well as fewer 180 day readmissions (p=0.044) than multiple substance users.

Conclusion: Compared to the national average (US Department of Health and Human Services), pts referred to BRIDGE appear more likely to have a history of SU (6.4% v 8.6%). Despite being younger and having lower comorbid burden, SU pts in this population had worse outcomes, as seen in prior studies. Additionally, they were less likely to attend a transitional care appointment, putting them at greater risk. Alcohol users, while older and sicker, had the best outcomes among SU pts; illicit substance users had the worst. Further research to identify the causes of these ED visits and readmissions, as well as targeted strategies to improve outcomes in this population are warranted.