Pre-hospitalization characteristics tied to health outcomes
Characteristics associated with black race, though not race itself, were found to be linked to higher mortality rates following acute myocardial infarction (MI), according to data from two U.S. registries.
In a sample of over 6,000 patients, the 5-year mortality rate was doubled among those who reported the highest prevalence of certain key characteristics -- lower socioeconomic status, history of MI and heart failure, poorer social support -- compared to those with the lowest prevalence (31.0% versus 15.5%, P<0.001), reported Garth Graham, MD, MPH, of Saint Luke's Mid-America Heart Institute in Kansas City, Missouri, and colleagues.
While these factors were all present in higher rates among the black population, once accounted for there was no significant mortality difference between black and white patients (adjusted HR 1.09, 95% CI 0.93-1.26, P
=0.37), they wrote in JAMA Network Open.
The 1-year mortality rates were also greater in those with a higher prevalence of these characteristics (12% versus 5%).
"It seems like it's based on race, but it's actually not based on race. It's based on these characteristics that are more prevalent in one race versus another," Graham told MedPage Today. This is important because most of the characteristics they observed in this study, particularly socioeconomic variables, are prevalent prior to a patient's hospitalization, he said.
Previous data have demonstrated that hospitals that treat high numbers of black patients have higher 90-day mortality rates after acute MI compared with those that happened to treat no black patients. And black patients may be less likely to receive certain interventions for MI. Graham said the current study's novelty lies in its identification that these key factors were independent of race.
His group collected data from 31 centers included in two prospective acute MI registries -- Prospective Registry Evaluating Myocardial Infarction: Events and Recovery (PREMIER) and Translational Research Investigating Underlying Disparities in Acute Myocardial Infarction Patients' Health Status (TRIUMPH). About a quarter of the patients in these were black (25.7%) and most were men (66.8%).
Black patients and white patients differed substantially in socioeconomic, psychosocial, clinical, demographic, and health status characteristics. White patients were slightly older on average (61 years versus 57), and more often were men (71% versus 55%).
The researchers divided observed characteristics into eight groups: demographic (age and sex); socioeconomic status (zip code, median income, educational level); social support (marital status, living alone); lifestyle factors (smoking status, history of cocaine use, body mass index); medical history (hypertension, diabetes, prior MI); clinical presentation (ST-elevation MI, cardiac arrest, initial hemoglobin); health status; and depressive symptoms.
Overall, patient factors explained 92% of the crude difference in mortality risk between black and white patients, the authors wrote.
A patient's zip code had the strongest association with race (P<0.001). Graham said this speaks to the point that "place matters" and location can be a distinct driver of health outcomes, reflecting things like income and access to education.
He said in the future he would like to see more research that focuses on socioeconomic drivers and more closely defines some of these pre-hospitalization characteristics driving these health outcomes.
The authors reported several limitations, including the fact that since the self-reported data came from two acute MI registries, it may not be geographically representative of the U.S. and does not include genomic data. Additionally, these registries were created over 10 years ago and the data may not be applicable to contemporary mortality rates in these populations. Lastly, the authors noted that there are additional characteristics that differ by race that were not included in this model.
Graham reported receiving payment from Aetna.
Co-authors reported grants from Saint Luke's Hospital, Johnson & Johnson, Medtronic, and the FDA, as well as fees from UnitedHealth Group, IBM Watson Health, Element Science, Aetna, the Centers for Medicare & Medicaid Services, and Hugo.
The TRIUMPH registry was sponsored by grants from the National Institutes of Health, and the PREMIER registry was sponsored by CV Therapeutics and the Cardiovascular Outcomes Research Consortium.
JAMA Network Open
Source Reference: Graham G, et al "Racial disparities in patient characteristics and survival after acute myocardial infarction" JAMA Network Open 2018; 1(7): e184240.
Read the original article on Medpage Today: Factors Independent of Race Linked to Higher Acute MI Mortality