Anticoagulation and Other Risk Factors for Clinically Relevant Bleeding after Medical Hospitalization: The Medical Inpatient Thrombosis and Hemostasis Study.

Introduction: Clinically relevant Bleeding after discharge from a medical hospitalization is associated with increased morbidity and mortality. There is limited knowledge of the risk factors for this bleeding.

Objective: To determine the risk factors for bleeding leading to rehospitalization after hospital discharge.

Methods: The study population consisted of primary care patients followed longitudinally from October 2010 to September 2019 for medical hospitalization and clinically relevant bleeding. People discharged alive from a medical hospitalization were followed for up to 90 days for post discharge bleeding requiring rehospitalization. Age and sex and length of stay-adjusted hazard ratios (HR) for candidate bleeding risk factors were estimated using Cox proportional hazards models.

Results: Over 9 years, there were 15,630 medical hospitalization discharges and 414 (2.6%) post-discharge clinically relevant bleeding events requiring re-admission. Clinical and patient factors related to post-discharge bleeding risk were increasing age, active cancer, liver disease, creatinine >2 g/dl, heart disease, and history of previous gastrointestinal or central nervous system bleeding. Hemoglobin <12 g/dl for women and <13.6 g/dl for men as well as a platelet count <50x10³ mm³ as well as anticoagulation at discharge were also associated with an increased risk for post-discharge clinically relevant bleeding.

Conclusion: Bleeding requiring re-hospitalization occurs after 2.6% of medical hospitalizations and has objective and readily identifiable risk factors. Findings suggest post-discharge clinically relevant bleeding may be predictable and quantifiable which could help increase the safety of anticoagulation decisions at discharge.