[Characteristics of heart rate variability in patients with vestibular migraine]

Objective: To analyze the characteristics of heart rate variability (HRV) in patients with vestibular migraine (VM) and to explore its possible mechanism. Methods: Forty-eight patients with VM [17 males and 31 females, age (36.2±9.2) years], 44 patients with migraine [15 males and 29 females, age (34.4±9.0) years], and 30 patients with health check-ups during the same period [12 males and 18 females, age (34.6±6.5) years old] were selected as study subjects. Ambulatory ECG monitoring was performed in all subjects, and the HRV characteristics of each group were analyzed from both daytime and nighttime time phases. Time domain parameters were analyzed: standard deviation of normal to normal (SDNN), root mean square of successive differences (RMSSD), and percentage of normal to normal intervals differing by more than 50 ms (pNN50). The parameters in the frequency domain were analyzed: high frequency power (HF), low frequency power (LF), and the ratio of low frequency to high frequency power (LF/HF). Statistical analysis of the data was performed using SPSS 26.0 software. Results: At night, RMSSD (F=6.694) and HF (F=9.434) were lower in the VM and migraine groups compared to the control group, while LF/HF (F=16.049) and LF (F=9.434) were elevated compared to the control group, with statistically significant differences (P<0.05 or P<0.01), while LF was significantly elevated in the VM group compared to the migraine group, with a statistically significant (P<0.05). On the daytime measurements, mainly LF was elevated in the vestibular migraine group compared with the control group, while RMSSD was decreased compared with the control group, with statistically significant differences (P<0.05). Conclusion: Autonomic dysfunction characterized by sympathetic hyperfunction and vagal hypofunction is present in VM patients and is more pronounced at night. In addition, the degree of autonomic dysfunction may be more pronounced in VM patients than in migraine patients.