Similar findings were observed after accounting for each demographic variable and co-varying medical condition of interest (history of vitamin B12 deficiency: 0.44 (0.25, 0.59); history of OSA: 0.45 (0.26, 0.60); BMI: 0.44 (0.22, 0.62); APOE Ɛ4 status: 0.44 (0.24, 0.60), sex: 0.43 (0.24, 0.58); level of intellectual disability: 0.46 (0.28, 0.61); all p < 0.001). Here, APOE is linked to obstructive sleep apnea syndrome.