Objectives:  CAD is an autoimmune hemolytic anemia caused by cold-reacting autoantibodies.  This research aims to characterize HRU in CAD patients and their matched controls.

Methods:  Nationwide patient registries were used to identify all cases of CAD (ICD10=D591A) in Denmark newly diagnosed between January 1, 1999 and July 1, 2016. Each CAD patient was matched (10:1) to a comparison patient from the general population by birth year, gender, and co-morbidities.

Comparisons:    Inpatient, outpatient and emergency room visits, and transfusion use was compared between CAD patients and matching controls using regression models.  RESULTS:  104 CAD patients and 1003 matched controls were included. Females comprised over half the cohort (53% CAD; 52% control), and 60% were 70 years or older (59% control).  Nearly half the cohort had 2+ comorbidities (45% CAD; 43% control).

Results: At six months prior to diagnosis, 31% of CAD patients experienced an inpatient hospitalization compared to 13% of matched controls (p= p<0.001).  Outpatient visits were experienced by 80% of CAD patients (vs. 47% matched controls; p<0.001), and emergency visits experienced by 19% of CAD patients (vs. 5% matched controls; p<0.001). At one year post-diagnosis 53% of CAD patients had an inpatient hospitalization (vs. 23% matched controls, p<0.001), 95% an outpatient hospitalization (vs. 59% comparison, p<0.001), and 19% an emergency visit (vs. 14% comparison, nonsignificant). Sixty-seven percent of inpatient hospitalizations among CAD patients were due to anemia and pneumonia. CAD patients had significantly higher mean inpatient length of stay (10.6 ± 18.6 vs. 2.7 ± 9.2 comparison, p=0.001). Emergency visits for CAD patients showed an increasing trend over time.

Conclusions: CAD patients used significantly more healthcare services than comparison patients both before and after their index date. The current management of CAD has a substantial impact on healthcare resource utilization, placing a burden on patients and healthcare systems.