Development of a Novel Intervention (Mindful Steps) to Promote Long-Term Walking Behavior in Chronic Cardiopulmonary Disease: Protocol for a Randomized Controlled Trial

Comparison of Physical Activity Patterns among Three Major Chronic Respiratory Diseases

Although the level of physical activity in daily life (PADL) plays a vital role concerning the health of subjects with chronic lung diseases, it remains uncertain how PADL patterns compare among different conditions. This study's objective was to compare the PADL levels of subjects with COPD, asthma and idiopathic pulmonary fibrosis (IPF); and to investigate PADL behaviour in different diseases' severity. Stable subjects who had not undergone pulmonary rehabilitation in the previous year were included. Subjects were divided into two subgroups according to disease severity: mild/moderate and severe/very severe. The primary outcome was time spent in moderate-to-vigorous physical activities (MVPA) (Actigraph GT3x) measured during one week over 12 h/day; other assessments included pulmonary function, peripheral muscle strength and exercise capacity. Comparisons among subgroups were corrected for age, BMI and sex. The analysis involved 119 subjects (47 asthma, 48 COPD and 24 IPF). Subjects with asthma had higher PADL levels than those with COPD and IPF (MVPA 18(14-22) vs. 8(4-12) vs. 7(1-12) min/day, respectively; p ancova = 0.002). Subjects with severe/very severe IPF had the lowest PADL level among all subgroups. Adult subjects with asthma have higher PADL levels than those with COPD and IPF, whereas patients with severe and very severe IPF are the most physically inactive subjects.

Day-night patterns in heart rate variability and complexity: differences with age and cardiopulmonary disease

STUDY OBJECTIVES

Heart rate variability (HRV) measures provide valuable insights into physiology; however, gaps remain in understanding circadian patterns in heart rate dynamics. We aimed to explore day-night differences in heart rate dynamics in patients with chronic cardiopulmonary disease compared with healthy controls.

METHODS

Using 24-hour heart rate data from patients with chronic obstructive pulmonary disease (COPD) and/or heart failure (n = 16) and healthy adult controls (older group: ≥50 years, n = 42; younger group: 20-49 years, n = 136), we compared day-night differences in conventional time and frequency domain HRV indices and a multiscale-entropy-based complexity index (CI1-20) of HRV among the 3 groups.

RESULTS

Twenty-four-hour HRV showed significant day-night differences (marked with "△") among younger healthy (mean age: 34.5 years), older healthy (mean age: 61.6 years), and cardiopulmonary patients (mean age: 68.4 years), including change in percentage of adjacent intervals that differ > 50 ms (△pNN50), high frequency (△HF), normalized low frequency (△nLF), ratio (△LF/HF), and △CI1-20. Among these, △LF/HF (2.13 ± 2.35 vs 1.1 ± 2.47 vs -0.35 ± 1.25; P < .001) and △CI1-20 (0.15 ± 0.24 vs 0.02 ± 0.28 vs -0.21 ± 0.27; P < .001) were significant in each pairwise comparison following analysis of variance tests. Average CI1-20 was highest in younger healthy individuals and lowest in cardiopulmonary patients (1.37 ± 0.12 vs 1.01 ± 0.27; P < .001). Younger healthy patients showed a heart rate complexity dipping pattern (night < day), older healthy patients showed nondipping, and cardiopulmonary patients showed reverse dipping (night > day).

CONCLUSIONS

As measures of 24-hour variability, traditional and complexity-based metrics of HRV exhibit large day-night differences in healthy individuals; these differences are blunted, or even reversed, in individuals with cardiopulmonary pathology. Measures of diurnal dynamics may be useful indices of reduced adaptive capacity in patients with cardiopulmonary conditions.

CITATION

Ma Y, Chang M-C, Litrownik D, Wayne PM, Yeh GY. Day-night patterns in heart rate variability and complexity: differences with age and cardiopulmonary disease. J Clin Sleep Med. 2023;19(5):873-882.

A Web-Based Mind-Body Intervention (Mindful Steps) for Promoting Walking in Chronic Cardiopulmonary Disease: Insights From a Qualitative Study

Background

Given the deleterious effects of physical inactivity in persons with chronic obstructive pulmonary disease (COPD) and/or heart failure (HF), interventions that promote long-term daily physical activity are needed. Mindful Steps, designed to promote walking behaviors in COPD and HF, is a multicomponent intervention that integrates mind-body content with other self-regulatory components. The aim of the current qualitative study was to characterize participants' experiences with Mindful Steps and understand the perceived influence of the intervention on walking and health.

Method

In the context of a pilot randomized controlled feasibility trial comparing the year-long Mindful Steps program to usual care among individuals with COPD and HF, semi-structured qualitative interviews were administered at 6- and 12-months. Interviews were audio recorded and transcribed. The constant comparative method was used to code transcripts, identify categories, and develop interrelated themes.

Results

Nineteen participants (63% female; Mage = 70.2 years, SD = 6.95) who were randomized to the intervention group completed the 6-month interview and 17 completed the 12-month interview. The pedometer with feedback, live group classes, and mind-body videos were described as the most helpful intervention components. Participants learned several strategies that helped their walking (e.g., breathing regulation and awareness, body awareness, mind-body techniques, pacing), described walking as enjoyable, and identified internal reasons for walking (e.g., to feel good). They also reported several physical and mental health benefits of the intervention. Some participants reported limited influence of the intervention on walking or health. Many participants continued to use the strategies they learned in the first half of the intervention at 12-months.

Conclusions

The mind-body content of Mindful Steps appeared to positively influence walking behaviors. Participants' experiences with the intervention helped to identify areas for future intervention refinement. Future quantitative work is needed to corroborate these qualitative findings and assess the efficacy of the intervention on long-term physical activity engagement.

Trial Registration

This trial is registered in Clinical Trials.gov, ID number NCT01551953.