title: Effect of Feedback Signal on Blood Pressure Self-regulation Capability in Individuals With Prehypertension or Stage I Hypertension: A Randomized Controlled Study.
abstract: OBJECTIVE
  We aimed to determine the efficacy of an 8-week direct blood pressure (BP) biofeedback training program for prehypertensive or stage I hypertensive patients with a particular focus on the impact of the authenticity of feedback signals on the efficacy of BP regulation.
  
  
  METHODS
  This study has a randomized, double-blind, parallel-group design.
  
  
  METHODS
  Fifty-nine individuals with ages from 18 to 64 years and who met the criteria for the diagnosis of prehypertenion or stage 1 hypertension participated in this study. The participants were referrals from physicians or community-dwelling volunteers. No participants had taken antihypertensive medication within the previous 2 months prior to enrollment. The participants were randomly assigned to the biofeedback group (n = 31) trained with real-time BP feedback signals or the control group (n = 28) trained with pseudofeedback signals. The primary outcome measures were systolic BP (SBP) and diastolic BP (DBP). Systolic BP and DBP were assessed at baseline, 1 week after training (week 9), and 8 weeks after training (week 16) in both groups. Only 54 participants had week 16 data.
  
  
  RESULTS
  The changes in SBP and DBP from baseline to week 9, from baseline to week 16, and from week 9 to week 16 were not significantly different between the groups (All P > 0.05). Both groups were able to significantly decrease BP after completing the training. A percentage of 45.2% of the participants in the biofeedback group and 63.0% of the participants in the control group lowered their SBP by 5 mm Hg or more at week 9. The SBP-lowering effects were also maintained for at least 8 weeks after the completion of training.
  
  
  CONCLUSIONS
  The equivalent magnitude of BP reduction between the 2 study groups suggests that repeated practice in BP self-regulation was more likely responsible for the efficacy of direct BP biofeedback training than was the type of feedback signals.
authors.affiliation: Mei-Yeh Wang, PhD Associate Professor, Department of Nursing, Cardinal Tien Junior College of Healthcare and Management, New Taipei City, Taiwan. Nen-Chung Chang, MD, PhD Professor, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taiwan; Division of Cardiology, Department of Internal Medicine, Taipei Medical University Hospital, Taiwan; Cardiovascular Research Center, Taipei Medical University Hospital, Taiwan. Ming-Hsiung Hsieh, MD, PhD Professor, Division of Cardiovascular Medicine, Wan Fang Hospital, Taipei Medical University, Taiwan. Chien-Tien Su, MD, MPH, PhD Associate Professor, School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taiwan; Director, Department of Family Medicine, Taipei Medical University Hospital, Taiwan. Ju-Chi Liu, MD, PhD Professor, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taiwan; Director, Division of Cardiovascular Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan. Yuh-Kae Shyu, PhD Assistant Professor, Department of Nursing, Fu Jen Catholic University, Taipei, Taiwan. Pei-Shan Tsai, PhD Professor, Graduate Institute of Nursing, College of Nursing, Taipei Medical University, Taiwan; Sleep Science Center, Taipei Medical University Hospital, Taiwan.
authors.forename: Mei-Yeh
authors.initials: MY
authors.lastname: Wang
authors.forename: Nen-Chung
authors.initials: NC
authors.lastname: Chang
authors.forename: Ming-Hsiung
authors.initials: MH
authors.lastname: Hsieh
authors.forename: Chien-Tien
authors.initials: CT
authors.lastname: Su
authors.forename: Ju-Chi
authors.initials: JC
authors.lastname: Liu
authors.forename: Yuh-Kae
authors.initials: YK
authors.lastname: Shyu
authors.forename: Pei-Shan
authors.initials: PS
authors.lastname: Tsai
mesh_terms: D000328:Adult; D001676:Biofeedback, Psychology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D000068356:Self-Control; D012720:Severity of Illness Index; D016896:Treatment Outcome; D055815:Young Adult