薛格連氏症候群(sjogren's syndrome,患者眼睛及口部乾燥,俗稱乾眼乾嘴症)是一種慢性、進行緩慢發炎性自體免疫之外分泌腺體病變，為僅次於類風濕性關節炎最常見的自體免疫風濕性疾病. 自律神經測試發現其心跳較低,HRV較高,且LF/HF較低,此副交感主導的體質常具保護心臟避免心律不整的功能,似乎可解釋此類病人猝死的機率較低
Heart rate variability in patients with Sjögren's syndrome.
Clin Rheumatol. 2000; 19(6):477-80 (ISSN: 0770-3198)

Tumiati B; Perazzoli F; Negro A; Pantaleoni M; Regolisti G
Santa Maria Nuova Hospital, Reggio Emilia, Italy. brunotum@tin.it

Heart rate variability (HRV) gives information about sympathetic parasympathetic autonomic balance. Our purpose was to determine whether HRV is abnormal in patients with Sjögren's syndrome. In 16 patients with Sjögren's syndrome and 30 matched controls, a short time analysis of HRV was performed for both the frequency and the time domain. In the time domain, patients tended to display a slower heart rate, greater R-R variability and higher standard deviation of the mean (SDNN) than did healthy subjects, but the differences were not statistically significant. In the frequency domain the spectral measures of HRV showed a slight reduction of LF and an increase of HF; as a result, the ratio between high and low frequencies, representative of sympathovagal modulation, was significantly reduced. Our data suggest an increase in the parasympathetic control of heart rate in patients with Sjögren's syndrome. This predominance in vagal tone could exert a protective and antiarrhythmic role in patients with primary Sjögren's syndrome, and may be relevant with reference to the lower incidence of sudden death in this disorder compared to other major autoimmune diseases.