title: Sympathomodulatory effects of Saam acupuncture on heart rate variability in night-shift-working nurses.
abstract: OBJECTIVE
  We assessed the effects of Saam (traditional Korean) acupuncture on the autonomic nervous system in night-shift nurses using power-spectral heart-rate variability (HRV) analysis.
  
  
  METHODS
  This study had a 2 × 4 cross-over design with a series of six (n = 1) controlled trials. Six night-shift nurses were randomly divided into two groups, and each nurse received four acupuncture treatments on the third day of night-shift work. One group started with Saam acupuncture (gallbladder jeonggyeok), while the other started with sham acupuncture. Saam acupuncture and sham acupuncture were applied in turn. HRV was measured before and after treatment. For statistical analysis, the results of the two groups were combined, and a Bayesian model was used to compare the changes in HRV values before and after treatment, between Saam and sham acupuncture.
  
  
  RESULTS
  As the ratio of low- to high-frequency power (LF/HF) for HRV increased on the third day of night-shift work in the pilot study, HRV measurements were made on the third day. Compared with sham acupuncture, Saam acupuncture reduced sympathetic activity; the overall median treatment effect estimate in LF normalised units decreased by -17.4 (confidence interval (CI): -26.67, -8.725) and that for LF/HF decreased by -1.691 (CI: -3.222, -0.3789). The overall median treatment effect estimate in HF normalised units increased by 17.41 (CI: 6.393, 27.13) with Saam acupuncture, suggesting an increase in parasympathetic activity.
  
  
  CONCLUSIONS
  Saam acupuncture may attenuate the imbalance between sympathetic and parasympathetic activities induced by night-shift work in nurses.
authors.affiliation: Department of Oriental Gynecology, College of Oriental Medicine, Kyung Hee University, Seoul, South Korea.
authors.forename: Deok-Sang
authors.initials: DS
authors.lastname: Hwang
authors.forename: Hyee Kwon
authors.initials: HK
authors.lastname: Kim
authors.forename: Jung Chul
authors.initials: JC
authors.lastname: Seo
authors.forename: Im Hee
authors.initials: IH
authors.lastname: Shin
authors.forename: Dal Ho
authors.initials: DH
authors.lastname: Kim
authors.forename: Yong-Suk
authors.initials: YS
authors.lastname: Kim
mesh_terms: D015669:Acupuncture Points; D015670:Acupuncture Therapy; D000328:Adult; D001341:Autonomic Nervous System / Q000502:physiology*; D001499:Bayes Theorem; D005260:Female; D006339:Heart Rate; D006801:Humans; D055670:Medicine, Korean Traditional; D009741:Nursing Staff, Hospital; D013312:Stress, Physiological; D014940:Work Schedule Tolerance / Q000502:physiology*; D055815:Young Adult