APOE and diabetes mellitus: After adjusting for age, gender, educational levels, APOE ε4 alleles, comorbidities (history of coronary heart disease, history of stroke, history of hypertension, history of diabetes mellitus, history of dyslipidaemia), and glomerular filtration rate, patients with more severe anaemia had lower CSF Aβ42 levels (p = 0.045, Fig. 2).