Cocaine is a well known risk factor for the development of early atherosclerosis and myocardial infarction (MI). Several studies in the medical literature have reported the increasing incidence of cocaine use in the American population and subsequent emergency room visits for acute coronary syndrome (ACS). In 2008, the American Heart Association (AHA) released guidelines for management of patients suspected to have cocaine–induced chest pain and subsequent MI. We sought in this study to explore the potential disparities in care pathways experienced by patients with cocaine induced MI.
Database query of two urban academic medical centers was undertaken using ICD–9–CM codes for myocardial infarction. We identified 672 consecutive patients admitted to the Coronary Care Unit of these centers following the introduction of the AHA guidelines in 2008. Out of these patients, 377 met study–inclusion criteria (admission diagnosis of MI and Age<65 years). Thus far, 50 charts have been reviewed and data including demographics, lab–work, imaging procedures and length of stay were collected according to a standardized protocol. Patients admitted with MI were classified into two groups: Cocaine Positive Group (defined as positive urine toxicology screen or self reported cocaine use) and Cocaine Negative Group (non–users or negative urine toxicology screen). Fisher’s exact test and Mann–Whitney U test were used to assess statistical significance among these two groups.
In our current study population, 12% were identified as having a cocaine–induced MI. These patients were 33% females and mostly of African American descent (67%, p<0.01). Patients with MI in the cocaine positive group (MI–CPG) were more likely to have Medicare or Medicaid as their primary insurance when compared to MI patients in the cocaine negative group (MI–CNG) (p=0.05). Comorbidities and home medications were similar between the two groups (all pns). Also, there was a trend towards a shorter length of stay (2.5 Vs 3 days) although not statistically significant in the MI–CPG relative to the MI–CNG. Interestingly, although MI–CPG patients were more likely than MI–CNG patients to undergo stress testing (50% Vs 14%), they were less likely to undergo PCI–stenting (0% Vs 64%) despite comparable (75% Vs 89%, p=0.43) atherosclerotic plaque burden (coronary stenosis >50%) on cardiac catheterization.
Our preliminary data suggest that patients with cocaine–induced MI are less likely to receive PCI or stenting despite their significant atherosclerotic plaque burden which suggests that cocaine positivity may influence the decision to intervene on a target lesion. While further research is needed, we can conclude that the presence or absence of a positive cocaine test may impact the care pathway of MI patients despite limited further knowledge of patients’ medical adherence or risk.