APOE and Alzheimer disease: Machine learning studies increasingly incorporate sex as a key variable, revealing sex-specific biomarkers and improving model performance in predicting disease status and progression.<h4>Conclusions</h4>Considering biological sex in AD research is essential for improving diagnostic accuracy, tailoring interventions, and health outcomes.<h4>Advances in knowledge</h4>This systematic review identifies sex-specific patterns in neuroimaging biomarkers of AD, influenced by cognitive reserve, hormones, APOE-ɛ4 genotype, inflammation, vascular health, and lifestyle.