Anemia subtypes increase the risk of peripartum cardiomyopathy and time to presentation independently of maternal race
K Sompel, E Shalowitz, E Kudron, S Son, D KaoAbstract
Background
Peripartum cardiomyopathy (PPCM) is a life-threatening condition that remains a leading cause of maternal mortality globally. PPCM has a higher morbidity and mortality in black populations, and a worse prognosis associated with delayed presentation. Previous studies have identified anemia as a PPCM risk factor, but the relationship between anemia subtypes and PPCM has not been investigated.
Purpose
Utilize large cohort study data to characterize the relationship between anemia subtypes and risk for PPCM with respect to race and time to presentation.
Methods
Public hospital discharge data were obtained for the states of Arizona (2003-19), Colorado (2006-9), Florida (2004-19), Louisiana (2010-2019), Maryland (2016-9), North Carolina (2015-9), New York (2015-9), South Dakota (2015-9), Washington 2003-19), and Wisconsin (2015-2019). Readmissions were determined using unique patient identifiers. Hospitalizations for childbirth as well as all comorbid conditions were identified using ICD-9 and -10 CM codes. Patient, pregnancy, and obstetric characteristics were determined using ICD-9 CM codes. The primary outcome was a diagnosis of PPCM defined as PPCM coded from 1 month antepartum (AP) to 150 days postpartum (PP). Secondary outcomes were AP vs. PP presentation of PPCM. Mothers were stratified by white vs. black race. Associations were determined using multivariable logistic regression.
Results
7,430,404 delivering mothers were identified of whom 5218 mothers were diagnosed with PPCM and 3,740 of whom were hospitalized after discharge for PPCM (71.7%) that was not present at delivery. Black mothers had an increased risk of presenting with PP PPCM (OR: 3.51, p < 0.001). Mothers who developed PPCM had higher rates of anemia, anemia of chronic disease (ACD), iron deficiency anemia (IDA), sickle cell disease (SCD), and sickle cell trait (SCT) than mothers who did not have PPCM (p< 0.001 for all). Black PPCM patients had higher rates of SCD (p<0.001) and SCT (p=0.032) compared to black non-PPCM patients, whereas white PPCM patients had similar rates of SCD compared to white non-PPCM patients (p=0.917). Multivariable analysis including race found that all anemia subtypes were associated with AP presentation of PPCM (Figure 1). ACD and IDA were also associated with PP PPCM whereas SCD and SCT were not. Stratification by race showed that anemia subtypes were associated with increased risk of PPCM in both white and black mothers (Figure 2). Magnitude of risk was greater for AP presentation in both races and greater for white mothers than black. Incidence of SCT in white mothers was low, but SCD was associated with increased risk of AP PPCM in white mothers. Both SCT and SCD were associated with AP PPCM in black mothers. SCD was not associated with PP PPCM in white or black mothers.
Conclusion
All anemia subtypes were associated with PPCM particularly for antepartum presentation. Risk associated with SCD appeared to be independent of race.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.