| Objective Bipolar disorder(BD)is a common serious mental illness,characterized by high recurrence rate,high disability rate and high suicide rate.Patients with BD have extensive cognitive impairment,mainly including executive function,attention,reaction time,memory and other impairments.These cognitive impairments have become an important factor for the impaired psychosocial function and the reduced quality of life in patients with BD,but currently,there is a lack of effective early detection of biomarkers for cognitive impairment.As biological markers of cell life,telomeres shorten as cells divide,regulate specific cell functions,and prevent damaged or genome-unstable cells from replicating.In addition,telomere can show different length dynamics according to cell type.Telomere length decreases with age,while cognitive ability decreases with age.Some studies have shown that cognitive function may be correlated with telomere length.However,there are few studies on telomere length and cognitive impairment caused by BD,most of these studies have focused on older people and people with dementia.It is not clear whether telomeres shorten the risk factors,consequences,or related factors of mental illness.There are few studies on the telomere length of bipolar disorder,and the research results are generally controversial.The relationship between telomere length and cognitive function of bipolar disorder has only been explored in the past two years abroad.In this study,MCCB was used to understand the cognitive function between patients in the stable phase of outpatient with BD and the healthy control group.Meanwhile,the correlation of leukocyte telomere length was compared to explore whether there is a correlation between the peripheral blood leukocyte telomere length and cognitive function in patients with BD in Chinese population.This would potentially facilitate early detection and treatment of the disease,thereby delaying the progression of cognitive impairment in patients with BD.Methods The Chinese version of MATRICS consensus cognitive battery(MCCB)was translated and evaluated by the team of Huilongguan Hospital in Beijing,which was developed by the National Institute of Mental Health of the United States.It was used to assess cognitive function in 30 stable patients with BD and 30 healthy subjects whose age,gender,and education level matched the patient group.The assessment included seven cognitive dimensions:processing speed,attention,working memory,verbal learning and memory,visual learning and memory,reasoning and problem solving,and social cognition.At the same time,peripheral blood of the patient group and the control group will be extracted for DNA extraction and telomere length measurement.The demographic data and clinical characteristics of the two groups were compared.Use SPSS to establish a database and conduct statistical analysis.Compared with the differences between the cognitive function and the length of the telomeres.To explore whether there is a correlation between the degree of cognitive loss and telomere length in patients with BD.Results The total MCCB score,SC,CF,DS,and ME scores of stable BD patients were significantly lower than those of healthy controls(P<0.05).Regression analysis found that the years of education in the stable bipolar disorder group were linearly positively correlated with HVLT-R,SS,BVMT-R,CPT-IP,MCCB total score(R~2=0.209,P=0.006<0.05;R~2=0,114,P=0.038<0.05;R~2=0.202,P=0.007<0.05;R~2=0.529,P=0.003<0.05;R~2=0.206,P=0.007<0.05).An analysis of the difference in telomere length between the two groups revealed that there were differences in telomere length between the two groups,with longer telomere length in the control group(Z=-3.297,P=0.001<0.05).The correlation analysis between the cognitive function assessment score and the telomere length of peripheral white blood cells showed that there was a significant correlation between telomere length and SC in patients with stable bipolar disorder(P=0.026<0.05).However,a further regression model suggests that telomere length is not an effective predictor of SC(P=0.080>0.05).Subsequent partial correlation analysis also indicated that telomere length was not associated with cognitive assessment scores in stable patients with BD.Conclusions In terms of cognitive function,the total MCCB score,SC,CF,DS,ME of patients with BD at stable stage were significantly lower than those of healthy control group,suggesting that the overall cognitive function,information processing speed,working memory and social cognition level of patients with BD at stable stage were impaired.In terms of telomere length,there were significant differences in telomere length between the stable BD group and the normal control group,and the telomere length of the stable BDpatients was shorter than that of the healthy control group.There was a significant correlation between telomere length and SC in patients with stable BD,but telomere length could not predict the SC effectively.There is no reliable data indicating that telomere length in peripheral blood leukocytes can predict cognitive impairment in patients with BD. |
