Association between plasma homocysteine levels and obstructive sleep apnoea in patients with ischaemic stroke.

Abstract We aimed to investigate the association between plasma homocysteine and obstructive sleep apnoea (OSA) syndrome in patients with ischaemic stroke. A total of 102 patients with ischaemic stroke were classified into four OSA groups based on their apnoea–hypopnoea index (AHI): absent (AHI  30/hour). The mean (±standard deviation) homocysteine levels in the four OSA groups were: absent, 8.98 ± 3.74 μmol/L; mild, 11.46 ± 3.31 μmol/L; moderate, 14.18 ± 4.36 μmol/L; and severe, 18.57 ± 4.56 μmol/L; and these differences were statistically significant ( p r  = 0.482, p R 2  = 0.539, p β for AHI = 0.259, β for folate = –0.400). In conclusion, the severity of OSA is significantly associated with elevated homocysteine levels in patients with ischaemic stroke, and this association is independent of other factors that cause elevation in homocysteine.