Smoking cessation in pregnant women: A randomized controlled trial investigating the effectiveness of an eHealth intervention including heart rate variability-biofeedback training.

BACKGROUND: Prenatal smoking and stress are associated with adverse health effects for women themselves and are risk factors for adverse outcomes of the child. Effective interventions are needed to support women with smoking cessation and reducing stress. The aims were (1) to test the effectiveness of an 8-week eHealth intervention targeting stress reduction and smoking cessation; (2) to examine whether stress reduction mediated the intervention effect on smoking behavior; (3) to test motivation to quit as a moderator; and (4) to investigate a dose-response effect of program usage. METHODS: Pregnant women were included if they were >18 years of age, < 28 weeks pregnant at recruitment, and currently smoking. In total, 156 consenting participants were randomly assigned to the intervention or active control condition. Study outcomes on smoking (yes/no, frequency, and quantity) were collected via online questionnaires at pre-intervention (baseline; t0), post-intervention (8 weeks after t0; t1), and follow up at two weeks (t2) and three months (t3) after birth. RESULTS: Smoking and stress reduced over the 8-week period in both conditions. The intervention effect on smoking was not mediated by stress reduction. Motivation to quit was found to moderate the intervention effect (smoking frequency and quantity) and a dose-response effect was found for program usage in the intervention for the reduction on smoking frequency and quantity. CONCLUSION: Program usage and motivation to quit are important for smoking reduction in pregnant women. Further research is needed to examine how the intervention could be improved to increase treatment effectiveness.

Validation of Photoplethysmography Using a Mobile Phone Application for the Assessment of Heart Rate Variability in the Context of Heart Rate Variability-Biofeedback.

OBJECTIVE: Heart rate variability-biofeedback (HRV-BF) is an effective intervention to reduce stress and anxiety and requires accurate measures of real-time HRV. HRV can be measured through photoplethysmography (PPG) using the camera of a mobile phone. No studies have directly compared HRV-BF supported through PPG against classical electrocardiogram (ECG). The current study aimed to validate PPG HRV measurements during HRV-BF against ECG. METHODS: Fifty-seven healthy participants (70% women) with a mean (standard deviation) age of 26.70 (9.86) years received HRV-BF in the laboratory. Participants filled out questionnaires and performed five times a 5-minute diaphragmatic breathing exercise at different paces (range, ~6.5 to ~4.5 breaths/min). Four HRV indices obtained through PPG, using the Happitech software development kit, and ECG, using the validated NeXus apparatus, were calculated and compared: RMSSD, pNN50, LFpower, and HFpower. Resonance frequency (i.e., optimal breathing pace) was also compared between methods. RESULTS: All intraclass correlation coefficient values of the five different breathing paces were "near perfect" (>0.90) for all HRV indices: lnRMSSD, lnpNN50, lnLFpower, and lnHFpower. All Bland-Altman analyses (with just three incidental exceptions) showed good interchangeability of PPG- and ECG-derived HRV indices. No systematic evidence for proportional bias was found for any of the HRV indices. In addition, correspondence in resonance frequency detection was good with 76.6% agreement between PPG and ECG. CONCLUSIONS: PPG is a potentially reliable and valid method for the assessment of HRV. PPG is a promising replacement of ECG assessment to measure resonance frequency during HRV-BF.

Stress- and smoke free pregnancy study protocol: a randomized controlled trial of a personalized eHealth intervention including heart rate variability-biofeedback to support pregnant women quit smoking via stress reduction.

BACKGROUND: Maternal smoking and stress during pregnancy are associated with adverse health effects for women themselves and are risk factors for adverse developmental outcomes of the unborn child. Smoking and stress seem to be intertwined in various ways. First, the majority of smoking pregnant women is of lower socio-economic status, which is associated with higher levels of perceived stress. Second, smoking women often report to smoke because they feel stressed. Third, quitting smoking often increases perceived stress levels initially. Therefore, effective interventions are needed to support women with smoking cessation by reducing stress. The aim of this study is to test the effectiveness of an eHealth intervention on stress reduction and smoking cessation. METHODS/DESIGN: The Stress- and Smoke Free Start of Life (SSFSL) study is a randomized controlled trial (RCT) comparing a personalized eHealth intervention with a control condition. Inclusion criteria for the women are: (1) > 18 years of age, (2) < 28 weeks pregnant at recruitment, (3) currently smoking. Consenting participants will be randomly assigned to the intervention or control group. Participants allocated to the intervention group will receive an 8-week intervention delivered on their smartphone. The application includes psycho-education on pregnancy, stress, and smoking (cessation); stress-management training consisting of Heart Rate Variability-biofeedback; and a personalized stop-smoking-plan. Participants in the control condition will be invited to visit a webpage with information on pregnancy, stress, and smoking (cessation). Study outcomes will be collected via online questionnaires, at four timepoints: pre-intervention (baseline; t0), post-intervention (8 weeks + 1 day after t0; t1), follow up at two weeks after birth (t2), and follow up at three months after birth (t3). The primary outcome measure is self-reported smoking cessation. Secondary outcomes include daily self-reported number of cigarettes smoked, perceived stress, pregnancy experience, birth outcomes, and negative affectivity scores of the baby. Moreover, the mediating effect of stress reduction on smoking cessation will be examined, and possible moderators will be tested. DISCUSSION: If the eHealth intervention is effective in smoking cessation among pregnant smoking women, it can be implemented as a tool into the health care in the Netherlands. TRIAL REGISTRATION: Netherlands Trial Register, ID: NL8156 . Registered on 11 November 2019.

The Effect of Heart Rate Variability Biofeedback Training on Mental Health of Pregnant and Non-Pregnant Women: A Randomized Controlled Trial.

In this study, we examined the efficacy of heart rate variability (HRV)-biofeedback on stress and stress-related mental health problems in women. Furthermore, we examined whether the efficacy differed between pregnant and non-pregnant women. Fifty women (20 pregnant, 30 non-pregnant; mean age 31.6, SD = 5.9) were randomized into an intervention (n = 29) or a waitlist condition (n = 21). All participants completed questionnaires on stress, anxiety, depressive symptoms, sleep, and psychological well-being on three occasions with 6-week intervals. Women in the intervention condition received HRV-biofeedback training between assessment 1 and 2, and women in the waitlist condition received the intervention between assessment 2 and 3. The intervention consisted of a 5-week HRV-biofeedback training program with weekly 60⁻90 min. sessions and daily exercises at home. Results indicated a statistically significant beneficial effect of HRV-biofeedback on psychological well-being for all women, and an additional statistically significant beneficial effect on anxiety complaints for pregnant women. No significant effect was found for the other stress-related complaints. These findings support the use of HRV-biofeedback as a stress-reducing technique among women reporting stress and related complaints in clinical practice to improve their well-being. Furthermore, it supports the use of this technique for reducing anxiety during pregnancy.

Physical activity, mindfulness meditation, or heart rate variability biofeedback for stress reduction: a randomized controlled trial.

In contemporary western societies stress is highly prevalent, therefore the need for stress-reducing methods is great. This randomized controlled trial compared the efficacy of self-help physical activity (PA), mindfulness meditation (MM), and heart rate variability biofeedback (HRV-BF) in reducing stress and its related symptoms. We randomly allocated 126 participants to PA, MM, or HRV-BF upon enrollment, of whom 76 agreed to participate. The interventions consisted of psycho-education and an introduction to the specific intervention techniques and 5 weeks of daily exercises at home. The PA exercises consisted of a vigorous-intensity activity of free choice. The MM exercises consisted of guided mindfulness meditation. The HRV-BF exercises consisted of slow breathing with a heart rate variability biofeedback device. Participants received daily reminders for their exercises and were contacted weekly to monitor their progress. They completed questionnaires prior to, directly after, and 6 weeks after the intervention. Results indicated an overall beneficial effect consisting of reduced stress, anxiety and depressive symptoms, and improved psychological well-being and sleep quality. No significant between-intervention effect was found, suggesting that PA, MM, and HRV-BF are equally effective in reducing stress and its related symptoms. These self-help interventions provide easily accessible help for people with stress complaints.