The Effect Of Bilateral Dorsolateral Prefrontal Cortex Low-frequency Repetitive Transcranial Magnetic Stimulation On BDNF And GABA In Patients With Primary Insomnia

Objective: This study aimed to investigate the therapeutic efficacy of bilateral dorsolateral prefrontal cortex low-frequency repetitive transcranial magnetic stimulation(rTMS)on patients with primary insomnia(PI),and to further examine the impact of rTMS on serum brain-derived neurotropic factor(BDNF)and ?-aminobutyric acid(GABA)in patients with PI.Further,their correlations were assessed,initially exploring the therapeutic mechanisms of rTMS.Methods: Eventually 32 eligible participants with primary insomnia(PI)were recruited from the outpatient department at Changzhou No.2 People's Hospital into this study from November 2016 to November 2017.All of them were diagnosed by PI according to International classification of sleep disorders(ICSD-3).Participants received 10 daily sessions(5 days/ per week,two days interval of weekend)of low-frequency(1Hz)rTMS over right and left dorsolateral prefrontal cortex(DLPFC).Before and after rTMS treatment,patients were assessed by Pittsburgh sleep quality index(PSQI)for the severity of sleep disturbance.Meanwhile,serum concentration of BDNF and GABA in patients was measured by ELISA and UPLC respectively.Finally,Pearson correlation analysis was performed to evaluate the correlation among PSQI score and BDNF and GABA.Results: After the treatment of rTMS,the PSQI score in patients was markedly decreased(from15.84±3.72 to 10.94±2.58 P<0.0001,compared to before treatment).The concentration of serum BDNF and GABA levels were significantly higher(85.20±78.77 vs 148.67±134.97,P=0.004;2.15±0.51 vs 2.98±1.00 P<0.0001;compared to before treatment).Pearson correlation analysis revealed that the change of PSQI score was negatively associated with the alteration of serum BDNF(r =-0.44,P =0.012)and the serum GABA level(r =-0.52,P =0.002).The increase in serum GABA level was positively associated with the serum BDNF level(r =0.55,P =0.001).Conclusion: 1.The bilateral DLPFC low-frequency rTMS significantly improves primary insomnia.2.The bilateral DLPFC r TMS increases the serum level of GABA and BDNF.3.Alleviation of PI by rTMS may result from the increase of the level of BDNF and GABA in the brain.