English proficiency and clinical outcomes in primary percutaneous coronary intervention

TO THE EDITOR: We have read with interest the article by Biswas et al.1 published in the journal. The article looks at whether a relationship exists between English proficiency levels and reperfusion times and outcomes in patients undergoing primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarctions (MIs). The patients in this study were categorized as limited English proficiency (LEP) if a language other than English was identified as their preferred spoken language on questioning. However, this is a subjective stratification and may not accurately compare English proficiency levels and objective tests of English proficiency. Additionally, the baseline characteristics are not of equivalent socioeconomic status, with the English proficient (EP) group being skewed towards a higher socioeconomic background. This may indicate that the results may not be solely due to a language barrier. Gusmano et al.2 have shown residents in lower income neighbourhoods are less likely to receive revascularization than those in higher income neighbourhoods. In supplementary table 4, the authors have indicated a delayed symptom to door time in patients from lower socioeconomic backgrounds; however, further analysis of door to treatment time, stratified for socioeconomic status, is required. Nesoff et al.3 in a rural American Indian population have described poorer post-MI-related health outcomes and delayed time to treatment in part due to distrust of healthcare systems, low overall and health literacy, and priority of family caregiving. To address the healthcare inequality and improve recognition of symptoms perhaps a targeted approach with culturally sensitive education is more beneficial than pamphlets and brochures in certain patient demographics, as this will target both literacy and cultural disparities.3 The authors have suggested that LEP may additionally be an indicator of heart failure (HF) related readmission within 30 days of PCI. Interestingly, the lack of engagement with cardiac rehabilitation which may contribute to HF within the 30 days following is present not only in Australia but also in other western countries and Iran.4 Both Australia and Iran face similar rates of referral and admission rates for cardiac rehabilitation, possibly attributable to cultural and linguistic barriers, socioeconomic, transportation, and logistic issues.4 This may indicate that LEP plays less of a role in referral and admission rates for cardiac rehabilitation. It is also noted that cardiac rehabilitation is underutilized in females, however, to reduce confounding the results for LEP and EP must be stratified by gender.4 Finally, though the authors have adjusted for comorbidities and procedural factors in both groups, it is possible that the disproportionately higher percentage of patients with diabetes mellitus (DM) in the LEP cohort compared to the EP cohort (28.1% vs. 14.9%, respectively) may be a confounding factor in the delayed symptom to door time and HF readmission in patients with LEP. It is known that DM can cause silent MIs and atypical presentations.5 The authors have noted an increased odds ratio for patients with DM (1.63) in HF readmission rates post-MI. As there is a larger proportion of patients with DM in the LEP cohort this may be a confounding factor in the extrapolation of English proficiency as a causal factor. Based on the studies cited above, we agree that there may be a role of language proficiency in the reperfusion times and outcomes for patients presenting with MI’s undergoing PCI. There is, however, a need to further stratify the results for socioeconomic background and DM to more clearly establish the exact role.