Introduction Clinical trials suggest that the burden of Acute Myeloid Leukemia (AML) to patients is substantial, with commonly observed comorbidities associated with disease and treatment including infections, hematologic, hemorrhagic, cardio/cerebrovascular, hepatic, and renal events. There are no large population-based real-world studies that assessed comorbidities and complications in AML patients overall and in particular, among the most challenging AML patients to treat: relapsed and/or refractory (R/R) patients.Objective To estimate frequency, incidence rates, and time to event for selected incident comorbidities and complications among AML patients and a subgroup with evidence of R/R disease, compared to non-cancer patients, leveraging a large adjudicated claims database.Methods A retrospective cohort analysis was conducted using the QuintilesIMS Real-World Data Adjudicated Claims - US (formerly known as PharMetrics Plus) database covering the years 2005-2015. Adult patients (>18 years) with at least one inpatient or outpatient claim indicating a diagnosis of AML (ICD-9-CM code: 205.0x) between January 1, 2006 and October 31, 2015 were identified, with index date defined as the date of the first observed AML diagnosis. A comparison patient of the same age, gender, geographic region, insurance type, and patient enrollment year without evidence of any cancer during baseline was matched 1:1 to each AML patient and assigned the same index date as the respective AML match. All patients were followed from 12 months prior to index (baseline) through 12/31/2015, disenrollment from the health plan, or death, whichever came first (with requirements of a minimum 2 months follow-up). Patients were considered to have evidence of refractory AML if they had >2 cycles of chemotherapy (new cycle defined as 14-60 days since previous chemotherapy; same cycle if <14 days from previous chemotherapy). Patients were considered to have evidence of relapsed AML if they had at least one diagnosis code indicating relapse (ICD-9 205.02), or received chemotherapy after a >60-day period with no evidence of chemotherapy, or diagnosis/procedure codes indicating repeated stem cell/bone marrow transplant. Study measures included frequency, incidence, and time to event for infections, hematologic, cardio/cerebrovascular, hepatic, hemorrhagic, renal events, and other events of interest during follow-up. Separate Multivariate Cox Proportional Hazards models were used to evaluate associations between AML and three specific outcomes (cardiovascular, type 2 diabetes [T2D], stroke) in the full study sample, controlling for baseline demographic (age, sex, region) and clinical characteristics (NCI comorbidity score, history of myelodysplastic syndrome).Results A total of 6,252 AML patients were identified and matched 1:1 to non-cancer patients (mean age: 54 years, 54% male in both groups). AML patients had higher NCI comorbidity index scores during baseline than non-cancer patients (0.9 vs. 0.3, p<0.001). These patients had higher incidence rates of selected comorbidities and complications during follow-up and shorter times to events than non-cancer patients (Table 1). The most common comorbidities and complications were neutropenia/febrile neutropenia (36.8%, 249.1 per 1,000 person-years [PYs]), pneumonia (21.6%, 130.3 per 1,000 PYs), and other hemorrhages (20.0%, 125.5 per 1,000 PYs). Results from Cox models suggest that AML patients had significantly higher risks of cardiovascular events (HR=3.9, 95% CI 3.4-4.6), T2D (HR=4.7, 95% CI 4.0-5.5), and stroke (HR= 2.6, 95% CI 2.2-3.1), all p<0.01. A subset of 2,804 study patients had evidence of R/R AML, including 1,225 (19.6%) with refractory (mean ± SD time to refractory disease 3.7 ± 2.6 months) and 1,579 (26.3%) with relapse (mean ± SD time to relapse 4.2 ± 7.4 months). Results were similar in terms of patterns of incident comorbidities and complications for the R/R subgroup.Conclusions This retrospective analysis found that AML patients had higher baseline comorbidities and higher rates of selected incident comorbidities and complications after diagnosis compared to non-cancer patients. The results were similar in R/R patients. This study provides real-world evidence of overall pre-disposition and risks among AML patients that might have clinical significance in terms of treatment, patient management, and risk communication. [Display omitted] DisclosuresNear:QuintilesIMS: Employment; Daiichi Sankyo Inc.: Research Funding. Iqbal:Daiichi Sankyo Inc.: Employment. Huang:QuintilesIMS: Employment; Daiichi Sankyo Inc.: Research Funding. Dhopeshwarkar:Daiichi Sankyo Inc.: Employment. Lang:QuintilesIMS: Employment; Daiichi Sankyo Inc.: Research Funding. Wallis:Daiichi Sankyo Inc.: Employment.