The Effect Of Low-frequency Repetitive Transcranial Magnetic Stimulation On Brain-derived Neurotropic Factor And Serotonin In Patients With Generalized Anxiety Disorder

Objective To explore the effect of bilateral low-frequency repetitive transcranial magnetic stimulation(r TMS)on serum brain-derived neurotropic factor(BDNF)and serotonin(5-HT)in patients with generalized anxiety disorder(GAD).Methods35 initially GAD participants were recruited from the outpatient department at Changzhou No.2 People’s Hospital into this study between November 2016 and November 2017.They were diagnosed as GAD according to Chinese classification of mental disorders(CCMD-3).During this study,7 patients were taken off.Eventually,28 patients were included into data analysis.All patients received 10 sessions(once daily,five days/ per week,two days interval of weekend)of low-frequency(1Hz)r TMS stimulation over right and left dorsolateral prefrontal cortex(DLPFC).Before and after r TMS treatment,participants were assessed by using Hamilton Anxiety Rating Scale(HARS)for the severity of anxiety.Meanwhile,serum concentration of BDNF and 5-HT in patients was measured by ELISA and UPLC,respectively.Further,Pearson correlation analysis was performed to evaluate the correlation between the change of HARS score and serum BDNF levels and serum 5-HT levels,as well as between the latter two variables.Results1.As compared with before treatment,the HARS score in patients after treatment markedly decreased(25.71±6.10 /15.43±4.12 scores,P <0.0001).2.The concentration of serum BDNF(771.52±660.63/ 429.93±307.16 pg/ml,P=0.0045)and 5-HT(455.84±247.82/ 291.23±138.23 ng/ml,P=0.0003)compared to pre-treatment were significantly higher after treatment.3.Pearson correlation analysis revealed that the change of anxiety scores was negatively associated with the change of serum BDNF(r=-0.62,P=0.0005)and the serum 5-HT level(r=-0.48,P=0.02),and the increase in serum 5-HT level was positively associated with the increase of serum BDNF level(r=0.63,P=0.0004).Conclusion1.Biateral low-frequency r TMS alleviates anxiety symptom in patients with generalized anxiety disorder(GAD).2.r TMS increases the serum level of BDNF and 5-HT.3.Alleviation of GAD by r TMS may be involved in the increase of the level of BDNF and 5-HT in the brain.