Heart Rate Variability and Skin Conductance Biofeedback: A Triple-Blind Randomized Controlled Study

Background It has been widely recognized that obstructive sleep apnea (OSA) is linked to cardiovascular disease. Yet, randomized controlled studies failed to demonstrate a clear cardiovascular benefit from OSA treatment, mainly because of poor adherence to continuous positive airway pressure (CPAP). To date, no prior study has assessed the effect of CPAP treatment on daytime resting heart rate, a strong predictor of adverse cardiovascular outcomes and mortality. Methods and Results We conducted a randomized controlled study in 39 participants with OSA and prediabetes, who received either in‐laboratory all‐night (ie, optimal) CPAP or an oral placebo for 2 weeks. During daytime, participants continued daily activities outside the laboratory. Resting heart rate was continuously assessed over 19 consecutive days and nights using an ambulatory device consisting of a single‐lead ECG and triaxis accelerometer. Compared with placebo, CPAP reduced daytime resting heart rate (treatment difference, −4.1 beats/min; 95% CI, −6.5 to −1.7 beats/min; P =0.002). The magnitude of reduction in daytime resting heart rate after treatment significantly correlated with the magnitude of decrease in plasma norepinephrine, a marker of sympathetic activity ( r =0.44; P =0.02), and the magnitude of decrease in OSA severity (ie, apnea‐hypopnea index [ r =0.48; P =0.005], oxygen desaturation index [ r =0.50; P =0.003], and microarousal index [ r =0.57; P <0.001]). Conclusions This proof‐of‐concept randomized controlled study demonstrates, for the first time, that CPAP treatment, when optimally used at night, reduces resting heart rate during the day, and therefore has positive cardiovascular carry over effects. These findings suggest that better identification and treatment of OSA may have important clinical implications for cardiovascular disease prevention. Registration URL: https:/// www.clinicaltrials.gov ; Unique identifier: NCT01156116.

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Natural Odor Inhalers (AromaStick®) Outperform Red Bull® for Enhancing Cognitive Vigilance: Results From a Four-Armed, Randomized Controlled Study

Perceptual and Motor Skills ◽

10.1177/0031512520970835 ◽

2020 ◽

pp. 003151252097083

Author(s):

Rainer Schneider

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Essential Oil ◽

Scanning Speed ◽

Energy Drink ◽

Blood Oxygenation ◽

Controlled Study ◽

Control Group ◽

Randomized Controlled ◽

Red Bull

Two recent publications demonstrated that specifically designed essential odor inhalers can enhance performance through (a) better selective attention and scanning speed and (b) physiological changes of increased heart rate variability and blood oxygenation. In this study, we compared two natural odor inhalers with a popular energy drink (Red Bull®) with regard to their ability to improve vigilance on a computerized attention test. We employed a four-armed, randomized controlled experimental design and used a modified version of the CompACT-Vi test module to investigate whether deep inhalations of essential oil scents improved vigilance. Both inhalers markedly improved the number of correctly identified targets and participants’ reaction time when compared to a control condition and consumption of Red Bull® (0.9 < d < 1.3). Additionally, the number of correctly solved mathematical sums during the second half of the vigilance test was substantially higher (d = 1.3) with the use of inhalers than for the control and Red Bull participants. Inhaler use was also associated with relatively increased heart rate variability (d = 1.0) as a mechanism of adapting to the experimental demands. Thus, short and deep inhalations of essential oil scents delivered directly to the nose improved vigilance, while a popular energy drink failed to show an effect beyond that of a control group receiving no stimulant.

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Effect of Transcutaneous Acupoint Electrical Stimulation on Post-Hemorrhoidectomy-Associated Pain, Anxiety, and Heart Rate Variability: A Randomized-Controlled Study

Clinical Nursing Research ◽

10.1177/1054773816685745 ◽

2017 ◽

Vol 27 (4) ◽

pp. 450-466 ◽

Cited By ~ 4

Author(s):

Mei-Ling Yeh ◽

Yu-Chu Chung ◽

Lun-Chia Hsu ◽

Shuo-Hui Hung

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Electrical Stimulation ◽

Postoperative Pain ◽

Anxiety Reduction ◽

Controlled Study ◽

Control Group ◽

Significant Group ◽

Pain Anxiety ◽

Randomized Controlled

Hemorrhoidectomy is the current best treatment for severe hemorrhoids, but it causes significant postoperative pain and anxiety, which is associated with heart rate variability (HRV). Transcutaneous acupoint electrical stimulation (TAES) was assumed to alleviate pain and anxiety, and modify the autonomic nervous system. This study aimed to examine the effects of TAES intervention on postoperative pain, anxiety, and HRV in patients who received a hemorrhoidectomy. A randomized-controlled trial with five repeated measures was conducted. The TAES group ( n = 39) received four 20-min sessions of electrical stimulation at chengshan (BL57) and erbai (EX-UE2) after hemorrhoidectomy, whereas the control group ( n = 41) did not. Data were collected using Visual Analogue Scale (VAS), State Anxiety Inventory (STAI), and HRV physiological signal monitor. TAES resulted in a significant group difference in pain scores, anxiety levels, and some HRV parameters. The findings indicate that TAES can help reduce pain and anxiety associated with hemorrhoidectomy. TAES is a noninvasive, simple, and convenient modality for post-hemorrhoidectomy-associated pain control and anxiety reduction.

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