Effect of drugs combined with vestibular rehabilitation training in treating persistent postural-perceptual dizziness and its relationship with dopamine receptor D2 TaqIA gene polymorphism

  Objective  To explore the effect of drugs combined with vestibular rehabilitation training in treating persistent postural-perceptual dizziness (PPPD) and its relationship with dopamine receptor D2 TaqIA gene polymorphism.

  Methods  Totally 60 patients with PPPD were randomly divided into control group (treated with sertraline) and combined group (treated with sertraline and vestibular rehabilitation training), with 30 cases in each group. Both groups were treated for 42 days. The therapeutic effect of the two groups was evaluated by the Dizziness Handicap Inventory (DHI), the Hamilton Anxiety Scale (HAMA), the Hamilton Depression Scale (HADA), the Eysenck Personality Scale (EPQ) and the Screening for Somatoform Symptoms-7 (SOMS-7). Polymorphism of dopamine receptor D2 TaqIA gene was detected by restriction fragment length polymorphism polymerase chain reaction (PCR-RFLP) and agarose gel electrophoresis.

  Results  The DHI score, SOMS-7 score, HAMA score and HADA score of the combined group on the 42^nd day of treatment were significantly lower than those of the control group (P < 0.05). The PCR bands in both groups were located at about 310 bp, the bands were clear and bright, and the amplification results were good. PCR-RFLP showed that there was only one 310 bp fragment in A1A1 polymorphic genotype of dopamine receptor D2 TaqIA, A2A2 genotype could be digested into two fragments of 180 and 130 bp, and A1A2 heterozygous genotype could produce three fragments of 310, 180 and 130 bp. There were significant differences in the distribution of A1A1, A1A2, A2A2 genotypes and frequencies of allele A1 and A2 between the two groups (P < 0.05). Correlation analysis and multiple regression analysis showed that the frequency of A1 gene was positively correlated with the stability of personality characteristics after treatment for PPPD, and was an independent factor.

  Conclusion  Drugs combined with vestibular rehabilitation training is effective in the treatment of PPPD, and the stable state after treatment is related to the high frequency of A1 site in dopamine receptor D2 TaqIA gene.