Sex Differences and Clinical Outcomes in Patients With Myocardial Infarction With Nonobstructive Coronary Arteries: A Meta-Analysis.

Background: Although myocardial infarction with nonobstructive coronary arteries (MINOCA) is more common in women, it is unknown whether sex is a risk factor for adverse outcomes in patients with MINOCA. We aimed to investigate the relationship between sex differences and outcomes of patients with MINOCA.

Methods And Results: A systematic literature search was performed in PubMed, Embase, and Cochrane databases from their inception until August 2023 for relevant studies. End points were pooled using the Hartung-Knapp-Sidik-Jonkman random-effects model as odds ratio (OR) with 95% CIs. Nine studies, involving 30 281 patients with MINOCA (comprising 18 079 women and 12 202 men), were included in the study. Women were older and had a higher prevalence of hypertension, diabetes, and stroke compared with men. The median duration of follow-up was 3.5 years, with an interquartile range of 2.2 to 4.2 years. Pooled analysis revealed no statistically significant difference in the risk of all-cause mortality (OR, 1.03 [95% CI, 0.87-1.22]), major adverse cardiovascular events (OR, 1.18 [95% CI, 0.89-1.58]), heart failure (OR, 1.32 [95% CI, 0.57-3.03]), stroke (OR, 1.13 [95% CI, 0.56-2.26]), and myocardial infarction (OR, 1.04 [95% CI, 0.29-3.76]) between the 2 groups. Regarding short-term outcomes, women had a significantly higher risk of in-hospital major adverse cardiovascular events compared with men (OR, 1.33 [95% CI, 1.16-1.53]) whereas there was no significant difference in the risk of in-hospital mortality (OR, 0.90 [95% CI, 0.64-1.28]) between the 2 patient groups.

Conclusions: Despite the differences in demographics and comorbidity profiles, there was no significant difference in the long-term outcomes for patients with MINOCA between sexes. However, it is noteworthy that women experienced a higher risk of in-hospital major adverse cardiovascular events compared with men.