Sex-based differences in myocardial perfusion imaging among diabetic Egyptian patients:a retrospective registry study.

Background: Diabetes mellitus (DM) markedly increases the risk of coronary artery disease (CAD), and myocardial perfusion imaging (MPI) is a key noninvasive tool for risk stratification. Sex-based differences in presentation, referral patterns, and diagnostic accuracy of MPI remain understudied, particularly in Middle Eastern populations with a high prevalence of diabetes. This study evaluated sex-based differences in the indications, results, appropriateness, and diagnostic accuracy of MPI among diabetic Egyptian patients. Methods: This retrospective observational registry study included 1,000 diabetic adults (648 men, 352 women) who underwent gated SPECT-MPI at our university hospitals. Demographic data, risk factors, ECG findings, stress modalities, MPI results, coronary angiography data, and appropriate use criteria (AUC) were analyzed. Results: Men were older than women (59.6 ± 8.0 vs. 57.0 ± 9.4 years, p < 0.001). Hypertension was more prevalent in women (84.1% vs. 67.6%, p < 0.001), whereas smoking was more common in men (30.4% vs. 0.3%, p < 0.001). Positive MPI results were more frequent in men (77.0% vs. 43.2%, p < 0.001), as were appropriate indications (79.3% vs. 53.4%, p < 0.001); inappropriate and uncertain indications were correspondingly more common in women. Reversible perfusion defects did not differ significantly by sex (23.6% in women vs. 21.2% in men, p = 0.523), whereas fixed defects were more prevalent in men (17.0% vs. 7.8%, p < 0.001). MPI accuracy relative to coronary angiography did not differ significantly between the sexes (91.7% in men vs. 86.3% in women, p = 0.103). Conclusion: Substantial sex-based disparities exist in MPI referral patterns, test positivity, and appropriateness among diabetic Egyptians. Women are more likely to receive inappropriate referrals and to have a lower positive diagnostic yield, underscoring the need for sex-sensitive clinical protocols.