Autonomic function in adults with allergic rhinitis and its association with disease severity and duration.

BACKGROUND: The association between allergic rhinitis (AR) and the autonomic nervous system (ANS) has recently received substantial attention. However, no studies have assessed how the heart rate variability (HRV) parameters are associated with duration and disease severity in AR.

OBJECTIVE: To compare the difference in autonomic conditions among individuals with AR of various durations and severities and healthy controls.

METHODS: We divided individuals with AR into subgroups based on duration and severity of disease. Next, we measured HRV, and the results were compared among subgroups and healthy controls.

RESULTS: High frequency (HF) and normalized high frequency (NHF) were significantly higher in the intermittent group than in the control group, whereas normalized low frequency (NLF) and the ratio of absolute LF to HF power (LF/HF) were significantly lower in the intermittent group than in the control group. Furthermore, NLF was significantly higher in the persistent group than in the intermittent group. HF and NHF were significantly higher in the mild group than in the control group, whereas NLF and LF/HF were significantly lower in the mild group than in the control group. The total nasal symptom and itchy nose scores were negatively correlated with NHF.

CONCLUSION: Our results indicate that patients with intermittent and mild AR have hypervagal activity and hyposympathetic activity, and the predominance lessens in patients with more persistent AR and severe symptoms. Further investigation of the mechanisms underlying the association between autonomic function and persistent and severe AR is needed.