Correlation of Serum Homocysteine with Attention and Executive Functions in Patients with Type I Stable Bipolar Affective Disorder

Bipolar affective disorder (BPAD) is a severe and persistent mental illness defined by the presence of recurrent mood episodes.Several studies have shown thatthe levels of homocysteine(Hcy)were elevated in BPAD patients, and high levels of peripheral Hcy have been associated with worse cognitive performance.

The current study aimed to examine the correlationof the level of Hcyin the serum with attention and executive functions in patients suffering from type I stable BPAD (BPAD I).

The present cross-sectional study was conducted on 170 participants in Huzhou, Zhejiang province, China, within July 2016 to December 2017.The subjects were divided into patients with schizophrenia (n=100) as the study group and healthy volunteers (n=70) as the control group. The Hcy and folic acid levels of fasting ulnar vein serum were determined using chemiluminescent microparticle immunoassay. Patient attention was evaluated by the Trail Making Test A (TMTA), and executive functions were assessed using the Trail Making Test B (TMTB) and Stroop Color and Word Test (SCWT).

The mean value of serum Hcy was significantly higher in the study group than thatreported for the control group(19.01±5.83 and 11.40±4.62; P<0.001). The results of several tests of attention(59.39±19.27 and 53.26±14.82; P=0.027)and executive functions (123.75±40.60 and 107.52±29.31; P=0.013) were poorer in the study group. The serum Hcy value positively correlated with the disturbance variables of the TMTA, TMTB, and Trail Making Test. However, the duration of the Stroop-C test (SCT) and SCWT negatively correlated with the correct number of the SCT and SCWT.

The increase in the level of serum Hcy closely correlated with the impairment of attention and executive functions in patients suffering from stable BPAD I.