Cold agglutinin disease burden: a longitudinal analysis of anemia, medications, transfusions, and health care utilization

Abstract

Cold agglutinin disease (CAD), a rare disease and subtype of autoimmune hemolytic anemia, is characterized by autoantibodies that bind to red blood cells at low temperatures. There is no established standard of care for CAD treatment and CAD cohort studies are limited by the rarity of the condition. The objectives of this study are to present the longitudinal experience of a CAD cohort from the United States, with a focus on anemia severity, use of medications and transfusions, and health care resource utilization. The Stanford Translational Research Integrated Database Environment database was used to retrospectively identify CAD patients diagnosed and treated at Stanford Health Care from 2000 to 2016. Twenty-nine patients were included in this analysis. There were 7.1 severe anemia events per patient-year observed over the follow-up time. For CAD patients treated at Stanford, there was a mean of 3.5 therapies per patient. Transfusions were given in at least 65% of the cohort with a mean of 11 transfusions per patient-year. For CAD-related health care use in the first year after disease onset, 93% used outpatient services with a median of 26 outpatient visits per patient. The data presented here likely represent the minimum number of events for these patients during this timeframe, as this single-center experience does not capture care from other providers. This longitudinal study of CAD patients demonstrates the severity of anemia and relapsing nature of the disease, even after administration of multiple therapies and transfusions.

Graphical abstract

Figure 1.

Severity of anemia among CAD patients in Stanford cohort, in 6-month intervals from disease onset (2000-2016). “No data” indicates that no hemoglobin readings were found in the Stanford patients’ records during the 6-month interval.

Figure 2.

Severity of anemia in relation to therapy administered at Stanford among CAD patients in Stanford cohort, in 6-month intervals from disease onset (2008-2016). “No data” indicates that no hemoglobin readings were found in the Stanford patients’ records during the 6-month interval.

Figure 3.

Incidence of transfusions at Stanford among CAD patients in Stanford cohort who had transfusions, in 6-month intervals from disease onset (2008-2016). For CAD patients who had a surgery, transfusions within 72 hours after surgery were removed from analysis. “No data” indicates either no transfusion information before 2008 or no transfusion information was found in the Stanford patients’ records during the 6-month interval.

Figure 4.

Example patient: clinical and treatment characteristics during follow-up time.

Figure 5.

CAD-related HRU at Stanford among CAD patients in Stanford cohort from disease onset (2008-2016). “No data” indicates periods without hemoglobin data or periods prior to 2008. HRU events that occurred during “No data” periods indicate that no hemoglobin readings were found in the Stanford patients’ records in that 6-month interval.