Downstream resource utilization following SPECT: Impact of age and gender.

Background: Previous studies have identified a downstream referral age and gender bias for invasive coronary anatomy evaluation after single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI). The present study evaluates if such bias still persists despite advancements in SPECT MPI and angiography. We hypothesized that women and patients ≥80 years old are less likely to undergo invasive coronary angiography after adjusting for clinical and scan variables.

Methods: Patients (n = 3824) who referred to a nuclear cardiology laboratory at a tertiary medical center were retrospectively identified. Regression analysis tested age (<55; 55-69; 70-79; ≥80 years) and gender as predictors of diagnostic angiogram at 90 days post-SPECT after adjustment for known CAD, CAD risk equivalent, SSS, SDS, and LVEF.

Results: Younger patients were more likely to undergo an angiogram as compared to octogenarians (77% more likely if <55 years old, 69% if 55-69 years old, and 52% if 70-79 years old). No effect was found for gender.

Conclusions: Older patients were less likely to be referred for angiogram as compared to their younger counterparts. Further study is needed to determine which factors guide this decision-making process in older adults and the influence of these factors on the referral bias.