A Retrospective Study of Comorbidities and Complications in Elderly Acute Myeloid Leukemia Patients in the United States

Background: Comorbidities in acute myeloid leukemia (AML) patients have been shown to increase with age. However, few studies have described the disease burden in elderly AML patients, a population generally underrepresented in clinical trials. We aimed to characterize the comorbidities and complications in elderly AML patients.

Patients And Methods: Patients aged ≥ 65 years with a primary diagnosis of AML were identified from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database (2000-2013) and were followed until the end of 2014. AML patients were matched 1:1 to noncancer patients by age, sex, geographic region, and race. A subset of patients with relapsed and/or refractory (R/R) AML was identified by modifying a previously validated algorithm. Baseline comorbidities and complications (eg, infectious, hematologic, cardiovascular) during follow-up were assessed using ICD-9 codes. Cox proportional hazards models were used to determine associations between AML and developing select complications.

Results: Compared to matched noncancer controls, AML patients (n = 3911) had higher baseline National Cancer Institute comorbidity index scores (1.81 vs. 1.63, P < .01), higher incidence rates (per 100 person-years) for all events of interest, and a higher risk of developing cardiovascular disease (hazard ratio = 4.61; 95% confidence interval, 4.07-5.21), type 2 diabetes mellitus (hazard ratio = 3.85; 95% confidence interval, 3.35-4.42), and stroke (hazard ratio = 2.60; 95% confidence interval, 2.32-2.92). R/R AML patients were younger, had lower National Cancer Institute comorbidity scores, lower incidence rates of events of interest, and a longer follow-up time compared to non-R/R AML patients.

Conclusion: Elderly AML patients had more comorbidities and higher rates of complications compared to noncancer controls. Considering comorbidities and complications in elderly AML patients may improve clinical decision making.