380. THE EFFECT OF BRIGHT LIGHT THERAPY ON SYMPTOMS AND COGNITIVE FUNCTION IN PATIENTS WITH SCHIZOPHRENIA

Abstract Background In patients with schizophrenia, circadian rhythm disturbances are commonly observed and related to a poorer clinical status. Bright Light Therapy (BLT) is a physical therapy that uses light exposure to treat diseases. Its mechanism may involve altering the circadian rhythm-related hormones through the eye-brain hormone regulation pathway, thereby improving the clinical symptoms of patients. Aims & Objectives This study aimed to investigate the clinical efficacy of BLT as an adjunct treatment for schizophrenia. Method 22 patients with schizophrenia were randomized into a BLT combined drug therapy group (n=11) and a drug therapy control group (n=11).The BLT group received 2 weeks of bright light therapy alongside drug therapy. Assessment scales included the Positive and Negative Symptom Scale (PANSS), Pittsburgh Sleep Quality Index (PSQI), and cognitive function tests. Results After 2 weeks of treatment, the total scores of PANSS and its three dimensional subscales in the BLT group were significant lower than those in the control group (t=-3.697，P=0.004；t=-2.116，P=0.034；t=-2.154，P=0.031；t=-3.378，P=0.006); There was no significant difference in PSQI, verbal learning test、verbal delayed recall test、TMT、 VFT、 digit sign 90 seconds, and digital span tests between the two groups after treatment. The reduction rate of PANSS total score and positive symptom scale score in BLT group were significant higher than those in control group, (t=2.288, P=0.037; t=2.253, P=0.036). The clinical response rate of BLT group and control group was 54.55% and 9.10%, respectively, the difference was statistically significant (F=20.551，P=0.000).The results of linear regression analysis show that 54.4% of the reduction rate of PANSS can be explained by the group with the interference of control variables excluded. In the BLT group, there were no significant adverse reactions during the treatment. Discussion & Conclusions BLT may be a safe and effective adijunctive treatment for improving symptoms of schizoprenia.