Chronic Obstructive Pulmonary Disease (COPD)

Xinrong Chen et al. (2024) · BMC medicine

This systematic review and network meta-analysis explored which kinds of breathing support, given while people with chronic obstructive pulmonary disease (COPD) do supervised exercise training, help most. COPD is a long-term lung disease that limits airflow and makes exercise uncomfortable, so many patients struggle to exercise hard enough to benefit from pulmonary rehabilitation. The authors compared six approaches: conventional oxygen through a nasal tube or mask, high-flow nasal cannula (HFNC, which delivers warmed, humidified air at high flow), noninvasive positive pressure ventilation (NPPV, a mask that pushes air in to ease breathing effort), nighttime NPPV, heliox (a helium-oxygen mix), and plain air. The protocol was registered with PROSPERO. The team searched five databases through December 2023 and included 35 randomized trials with 1321 patients from 19 countries. All had stable, severe COPD (GOLD stage III or IV), with average ages from 59 to 76 and mostly men. Programs ran 6 to 12 weeks, with two to three sessions weekly of 30 to 45 minutes. A network meta-analysis lets treatments be ranked even when they were not directly compared. Outcomes included the 6-minute walk test (distance covered in 6 minutes), peak work rate, endurance time, breathlessness on the Borg scale, oxygen uptake, and quality of life. NPPV performed best. Compared with plain air, NPPV improved walk distance (SMD 0.36, where SMD is a standardized effect size), peak work rate (0.69) and peak oxygen uptake (0.75), and it was the only option to do so on those measures. Versus oxygen, NPPV also improved walk distance (0.44) and peak work rate (0.56). It also lowered blood lactate and improved tidal volume and minute ventilation. For endurance time, both NPPV (0.38) and oxygen (0.31) beat air, and HFNC ranked highest. Breathlessness dropped more with NPPV (-0.47), HFNC (-0.46) and oxygen (-0.36) than with air. No therapy changed quality of life significantly, heliox showed no benefit, and nighttime NPPV did not reach significance. The evidence quality ranged from critically low to moderate. The authors suggest that NPPV is the most promising option for stable severe COPD during pulmonary rehabilitation exercise, while noting that results apply only to GOLD stage III or IV disease. They state limitations including small, varied trials, few direct comparisons, high risk of bias in many studies, and unclear best device settings. They call for larger trials that also examine safety, feasibility, cost and personalization. The authors add that the analysis used change from baseline to limit differences between groups, and that the lack of direct comparisons between some therapies weakens confidence in the rankings.

Sebastian Rutkowski et al. (2020) · International journal of chronic obstructive pulmonary disease

This randomized controlled trial with 106 hospitalized patients with chronic obstructive pulmonary disease (COPD, a lung condition marked by chronic airflow limitation) examined whether adding video-game-based virtual reality (VR) training to a two-week pulmonary rehabilitation program could improve physical fitness beyond standard exercise training alone. Pulmonary rehabilitation, a structured program of supervised exercise, is the most effective way to improve exercise tolerance in COPD, but many national health systems fund only two to three weeks of it rather than the six or more weeks recommended internationally, so the study tested whether a low-cost gaming console could make the most of that shorter window. 106 patients (ages 50-70, roughly evenly split by sex) completed a five-day-a-week, two-week inpatient program. All groups received the same traditional rehabilitation (breathing exercises, stretching, and relaxation training). One group added stationary-bike endurance training, a second added both endurance training and VR sessions, and a third replaced endurance training with VR sessions using an Xbox 360 console and Kinect motion sensor running four exercise mini-games. Fitness was measured before and after the program with the Senior Fitness Test, a six-part battery covering arm and leg strength, flexibility, balance, agility, and a six-minute walk test. All three groups improved on nearly every fitness measure over the two weeks. The group combining traditional endurance training with VR improved significantly more than endurance training alone on all six fitness components, including six-minute walking distance (p<0.011), arm strength (p<0.003), and agility/balance (p<0.000). The VR-only group, despite performing no stationary-bike training at all, still outperformed the endurance-only group on arm strength (p<0.000), leg strength (p<0.001), and walking distance (p<0.031), reaching a walking-distance improvement of roughly 35 meters, above the 30-meter threshold generally considered a clinically meaningful gain, a threshold the endurance-only group did not reach. No adverse events were linked to the VR sessions in either VR-containing group. The authors suggest that gaming-based exercise may help patients stay motivated once they leave the structured hospital setting, since an activity framed as play may be easier to sustain than repetitive cycle-ergometer sessions. The findings are limited to a single Polish hospital, a two-week window with no follow-up on whether gains lasted, and a trial that was registered only after it began; patients also knew which group they were in, since VR sessions could not be disguised. Longer studies with sustained follow-up would be needed before drawing conclusions about lasting benefit.

Qing Li et al. (2025) · Journal of occupational health

This randomized crossover trial studied 30 Japanese men, average age 63, who were at risk of developing chronic obstructive pulmonary disease (COPD) — a common lung condition that narrows airways and makes breathing harder over time, and one of the world's leading causes of death. Each man spent one day forest bathing (Shinrin-yoku, the Japanese practice of mindfully immersing yourself in a forest) in a cypress forest, and another day walking a similar distance through a nearby city, in random order — so each person acted as their own comparison. Both walks covered the same distance at the same gentle pace under the guidance of a certified forest therapist, and participants avoided alcohol and ate the same meals throughout the 3-day trip. Researchers measured inflammation markers and oxygen levels in the blood before and after each walk, checked blood-oxygen saturation with a fingertip sensor, and had participants complete standard questionnaires about breathing symptoms, sleep quality, mood, and fatigue. Forest bathing lowered several inflammation markers (CRP, IL-6, and α1-antitrypsin) significantly more than the city walk did, and raised blood-oxygen saturation, while the city walk produced no such oxygen improvement. COPD-related breathing symptoms dropped significantly after forest bathing but stayed about the same after the city walk. Sleep quality improved across most measures after forest bathing, and mood scores showed less anger, confusion, depression, and anxiety, with people feeling notably more energetic than after the city walk. Fatigue and physical discomfort also eased more after time in the forest. Both walks used the same amount of physical effort (confirmed by matched blood-lactate levels), meaning the extra benefits of the forest walk likely came from the forest environment itself — its cleaner air, plant-released aromatic compounds (phytoncides), and calming, multisensory setting — rather than simply from walking. In people at risk of COPD, these results suggest that spending a day in a forest, walking gently and mindfully, may ease inflammation, improve breathing-related symptoms, and boost mood and sleep more than an equivalent walk in the city. Forest bathing is not a treatment for COPD; the authors caution that diagnosed COPD calls for medical supervision and flat, easy trails. The study is small (30 men) and tested only two single days, so it can't yet say whether these benefits last with regular practice or apply to women or other age groups.