Comment
In this retrospective study of patients diagnosed with ATAA, we found that patients with lower socioeconomic status had lower rates of follow-up with a cardiovascular specialist and were less likely to receive timely follow-up imaging. In turn, these patients suffered worse outcomes in that they were more likely to present with symptoms at time of aortic surgery or die before ever being followed up. To date, there have been no studies that we know of examining the influence of SES on thoracic aortic aneurysm surveillance.
The majority of patients in our cohort had moderate-sized aneurysms (<5cm) without other significant risk factors (i.e. genetic syndromes), a population in which the appropriate interval for surveillance imaging is currently debated.16, 19, 20The 2010 ACCF/AHA Task Force guidelines recommend all patients with TAA be managed by a cardiologist or cardiac surgeon; however, they leave the imaging interval to the discretion of the provider.4While annual CT scan is reasonable after initial aneurysm detection or in genetically predisposed patients with stable ATAA size, we expect that intervals will be longer for those without associated risk factors. For this reason, we used a conservative interval of 2 years from last CT scan to evaluate whether patients were receiving regular surveillance with CT or echocardiography. We observed that patients in the ADI quartile with lowest SES were less likely to receive surveillance imaging for ATAA aneurysm within 2 years of last CT scan, even after adjusting for common comorbidities that warrant thoracic imaging. While we are unable to establish a causal relationship, the observed difference in successful referral to a cardiovascular specialist indicates the need for improved systems for establishing longitudinal follow-up in individuals with decreased access to care.
Several studies have linked lower patient socioeconomic status with disparities in cardiovascular healthcare.6, 21, 22While our study lacks information about previously employed measures of SES, such as insurance status and income level, the use of ADI in health outcomes research is growing as it provides a more comprehensive measure of disadvantaged status while offering greater granularity than estimates based on zip code alone. Within cardiac surgery, a study by Patrick et al. utilized ADI to show that lower SES is associated with receipt of fewer arterial conduits during CABG, resulting in worse long-term survival.10 Lower income patients with coronary artery disease also face significant financial barriers to accessing routine care, such as medical checkups, Hgb A1c and lipid measurement, and antihypertensive treatment.23 This is particularly important for patients with TAA as a higher incidence of TAAs has been observed in more socioeconomically deprived individuals, perhaps due to the greater prevalence of uncontrolled hypertension which is a known risk factor for adverse outcomes in TAA.20, 24 Prior to this, the understanding of how socioeconomic barriers impact outcomes in patients with TAA was limited to only to survival after aortic dissection.13, 14 This catastrophic outcome is avoidable with periodic monitoring and elective intervention.
Several previous studies have observed Black patients to experience poorer cardiovascular healthcare and outcomes.25-27The low number of non-white patients in our sample made it difficult to evaluate differences in care associated with race. The lack of statistically significant association between surveillance care and race may be due to the collinearity between ADI and race, with ADI being a variable accounting for a larger variation in the care.
Ultimately, in our study, patients of lower SES experienced inadequate aneurysm surveillance and follow-up and greater likelihood of presenting for surgery with symptoms. This finding is supported by another recent study of 51,282 patients from the Society for Thoracic Surgeons (STS) Database, which found that both uninsured as well as Medicaid patients were significantly more likely to undergo nonelective thoracic aortic operation than privately insured patients (RR 1.77 [1.70-1.83] and 1.18 [1.10-1.26], respectively).12 Though our study lacks data on cause of mortality, the worrisome observation that 92% of patients in the lowest SES quartile (Q4) presented with symptoms is concerning for the subset of patients who may have died from aneurysm complications before having a chance to be seen.
Healthcare institutions must be proactive in engaging marginalized populations via interventions targeted at both patients and providers. This may take the form of automatically generated alerts to ordering providers when radiographic scans detect aneurysms above a certain size. In addition, public health initiatives should expand outreach to marginalized communities with education regarding the significant mortality associated with TAAs and the treatable nature of the disease.