(P112) PREVALENCE OF ANEMIA IN CARDIAC AMYLOIDOSIS AND ASSOCIATION WITH CLINICAL FACTORS AND OUTCOMES

Background: Cardiac amyloidosis (CA), most commonly light chain (AL) or transthyretin (ATTR), causes a restrictive cardiomyopathy with progressive heart failure. Although anemia is a common comorbidity in heart failure, associated with adverse outcomes, the prevalence, incidence, and outcomes of anemia associated with CA have not been previously reported.

METHODS AND RESULTS: We performed a retrospective cohort study of patients seen in a dedicated Cardiac Amyloidosis Clinic between January 2010 and September 2019. Baseline demographic, clinical, laboratory, and imaging data were collected, as well as data on incident anemia and clinical outcomes. Factors associated with baseline and incident anemia were identified. Univariable and multivariable regression models were used to identify associations with clinical outcomes. We identified 135 patients who were diagnosed with CA during the study period. The mean age was 69.7 years and 77.6% of patients were male. Amyloid type was AL in 38.5 and ATTR in 61.5%. At baseline, mean left ventricular ejection fraction (LVEF) was 50.5%, mean glomerular filtration (GFR) rate was 61 mL/min/m2, and mean hemoglobin was 132 g/L. Mean values for mean corpuscular volume (MCV), ferritin, and serum iron were 91 fL, 193 ug/L, and 11.6 umol/L, respectively. Anemia was present at baseline in 38% and incident anemia developed in an additional 21% during follow up. Compared to those without anemia at baseline, anemic patients had lower baseline GFR (53 vs. 66 mL/min/m2, p=0.006), lower MCV (90 vs. 92 fL, p=0.03), and lower baseline serum iron (10 vs. 13 umol/L, p=0.004). Among ATTR patients, anemic patients were more likely to report a history of heart failure than non-anemic patients (84% vs. 62%, p=0.048). There were no differences in outcomes between anemic and non-anemic patients in the overall cohort. After a median follow-up time of 957 days in ATTR patients, baseline anemia was associated with increased risk of death during follow-up (OR 4.3, p=0.01). When adjusted for age, LVEF, and baseline GFR, however, anemia was no longer associated with risk of death.

Conclusion: Anemia is prevalent in CA patients and associated with lower GFR and serum iron levels. Further investigation is needed to better elucidate mechanisms of anemia in this population and whether they differ from those in other HF patients. Associations between anemia and mortality in ATTR patients can be explained by other associated factors, although our sample size may have reduced our power to detect true associations.