The benefit of exercise training in pulmonary hypertension: a clinical review

High relative humidity environment alleviates hypoxia-induced pulmonary arterial hypertension in mice

The environment has long been considered a crucial factor influencing the onset and progression of pulmonary diseases. Environmental therapy is also a practical treatment approach for many conditions. While research has explored the effects of factors like air pressure and oxygen concentration on pulmonary arterial hypertension (PAH), the impact of air humidity on PAH has not been investigated. In this study, we examined the role of different air humidity levels in a mouse model of PAH by controlling relative humidity. We induced PAH in mice using 10 % hypoxia, which led to significant thickening of the pulmonary vasculature, elevated right ventricular systolic pressure, and an increased right ventricular hypertrophy index (RVHI). However, when exposed to an environment with 80-95 % relative humidity, there was a marked reduction in the extent of pulmonary vascular remodeling, decreased vascular thickening, and lower RVHI, effectively preserving right heart function. Notably, changes in the Bmpr2/Tgf-β signaling pathway were significant and may play a pivotal role in this protective effect. In summary, our findings indicate that high relative humidity confers a protective effect on hypoxia-induced PAH in mice, providing novel insights into potential treatments for PAH.

Exercise Training as a Non-Pharmacological Therapy for Patients with Pulmonary Arterial Hypertension: Home-Based Rehabilitation Program and Training Recommendations

Pulmonary arterial hypertension (PAH) is a chronic and progressive disorder with a poor prognosis associated with non-specific symptoms, including general weakness, shortness of breath on exertion, and decreased muscle strength and endurance. Despite recent significant progress in the field of PAH therapy, many patients are still characterized by a dynamic course of the disease, a significant reduction in physical performance, a constantly deteriorating quality of life, and limited activity in everyday life. Thus, the main goal of PAH therapy is to ensure an acceptable level of quality of life as early as possible in the course of the disease, reduce the progression of symptoms and, if possible, improve the prognosis, which is still poor. The perception of the importance of activity and exercise has changed significantly in recent years, and rehabilitation dedicated to PAH patients is now considered to be one of the new adjuvant treatment options. Currently, there is insufficient data on what form, frequency, and intensity of exercise are required for the best results. Nevertheless, exercise training (ET) is necessary in order to reverse the accompanying PAH impairment of exercise capacity and, without additional clinical risk, to maximize the benefits of pharmacotherapy. This review summarizes the current state of knowledge on the rehabilitation of PAH patients and presents the available rehabilitation models. In addition, it includes a ready-to-use, illustrated, safe home rehabilitation program with recommendations for its use. Utilizing ET as an adjuvant treatment option to improve the functional capacity and quality of life of patients may enhance the clinical effectiveness of therapeutic management and contribute to the improvement of the quality of care for patients suffering from PAH. The beneficial effect of exercise training on the development of symptoms improves the clinical course of the disease, and a lower incidence of adverse events can lead to a reduction in health care expenditure.

Pulmonary arterial hypertension: An overview

ABSTRACT

This article discusses the pathophysiology, risk factors, clinical manifestations, diagnostics, and pharmacologic treatment of pulmonary arterial hypertension, as well as nursing considerations for caring for patients with this rare disease.

Long-Term Effect of an Exercise Training Program on Physical Functioning and Quality of Life in Pulmonary Hypertension: A Randomized Controlled Trial

The aim of this study was to evaluate the effects of a 6-month combined aerobic and strength exercise training program on functional and psychological aspects and health-related quality of life in patients with PH and to evaluate its longer-term impact. In total, 22 stable patients (mean age 53.9 ± 13.8, 13 female) with pulmonary hypertension of World Health Organization (WHO) class I-III participated in a nine-month study. They were randomly assigned into two groups: Group A participated in a 6-month combined aerobic and strength exercise training program, whereas Group B remained untrained. All patients underwent physical and psychological assessment at baseline and at month 6 (after completing the exercise program) and physical assessment after 9 months (3 months posttraining). After the 6-month exercise training program, patients of Group A significantly improved their physical (6MWD, STS 10 rep, STS 20 rep, TUG, lower limb strength, cardiopulmonary exercise time, METs, peak VO₂, VCO₂, and VE/VCO₂ slope) and psychological aspects (SF-36, STAI, and BDI). Between the two groups, differences were observed at the 6MWD (95% CI: 36.2-64.6, η² = 0.72), STS 10 rep (95% CI: 6.6-2.2, η² = 0.4), STS 20 rep (95% CI: 10.8-2.4, η² = 0.34), lower limb strength (95% CI: 7.2-3.6, η² = 0.38), cardiopulmonary exercise time (95% CI: 0.1-3.3, η² = 0.2), and VCO₂ (95% CI: 0.1-0.5, η² = 0.2). Additionally, psychological changes were noted at SF-36, PCS (95% CI: 3.6-14.8, η² = 0.35), MCS (95% CI: 1.3-16.1, η² = 0.22), TCS (95% CI: 1.3-16.1, η² = 0.22), and STAI (95% CI: 1.8-28.2, η² = 0.18). The favorable results of exercise were maintained at the 3-month posttraining follow-up assessment. No exercise-induced complications were observed throughout the study. In conclusion, a long-term exercise training program is a safe and effective intervention to improve functional status, psychological aspects, and health-related quality of life in patients with PH.

'Tired, afraid, breathless … .' An international survey of the exercise experience for people living with pulmonary hypertension

Patients with pulmonary hypertension are more sedentary than the general population, but attitudes and experiences that may influence their exercise behaviour remain poorly understood. This study identified patterns of behaviour, attitudes towards exercise, barriers and enablers of exercise for people living with pulmonary hypertension. Accessibility of rehabilitation services from a patient perspective was also explored. A voluntary, international survey of people living with pulmonary hypertension was conducted, with mixed quantitative and qualitative data collection. Data from 187 participants in 19 countries were included in the analyses. In total, 52% (95/183) of people with pulmonary hypertension reported that they attempted to engage in regular physical activity. This was less than the proportion who did so prior to diagnosis (61%, 112/184, p = 0.006) and was accompanied by uncertainty and anxiety about exercise. In total, 63% (113/180) of the cohort reported experiencing previous adverse events while exercising, which was associated with a greater likelihood of ongoing exercise concerns and anxiety. Fear, frustration and uncertainty about exercise were noted as common barriers to engaging in exercise with pulmonary hypertension. Other barriers to exercise included intrinsic factors such as debilitating breathlessness and fatigue, and external factors such as cost and access to appropriate services. Most respondents (76%, 128/169) did not have access to a multi-disciplinary rehabilitation service, although an overwhelming majority (92%, 159/172) reported that this would be helpful. Respondents rated education; a supervised, structured exercise programme; and psychology input as the most important components of a multi-disciplinary rehabilitation service for pulmonary hypertension. Health professionals must work together with consumers to co-design rehabilitation services that will facilitate exercise and increased activity for people living with pulmonary hypertension.

Effects of Different Types of Exercise Training on Pulmonary Arterial Hypertension: A Systematic Review

Pulmonary arterial hypertension (PAH) represents a chronic progressive disease characterized by high blood pressure in the pulmonary arteries leading to right heart failure. The disease has been a focus of medical research for many years due to its worse prognosis and limited treatment options. The aim of this study was to systematically assess the effects of different types of exercise interventions on PAH. Electronic databases were searched until July 2019. MEDLINE database was used as the predominant source for this paper. Studies with regards to chronic physical activity in adult PAH patients are compared on retrieving evidence on cellular, physiological, and psychological alterations in the PAH setting. Twenty human studies and 12 rat trials were identified. Amongst all studies, a total of 628 human subjects and 614 rats were examined. Regular physical activity affects the production of nitric oxygen and attenuates right ventricular hypertrophy. A combination of aerobic, anaerobic, and respiratory muscle training induces the strongest improvement in functional capacity indicated by an increase of 6 MWD and VO₂peak. In human studies, an increase of quality of life was found. Exercise training has an overall positive effect on the physiological and psychological components of PAH. Consequently, PAH patients should be encouraged to take part in regular exercise training programs.

Effectiveness and safety of exercise training and rehabilitation in pulmonary hypertension: a systematic review and meta-analysis

Background

Pulmonary hypertension (PH) is a chronic progressive disease characterized by increasing pulmonary vascular resistance, poor prognosis and high disability rate. Although many targeted drugs for PH have been put to clinical use, most patients still have poor exercise tolerance and quality of life. Exercise training is considered to further improve exercise capacity and quality of life in patients with PH, but it has not been fully studied and utilized. The aim of this systematic review and meta-analysis is to evaluate the effectiveness and safety of exercise training in patients with PH.

Methods

A search was conducted for the meta-analysis using the databases PubMed, Embase, Cochrane Library, including literature published before December 2018. The primary outcome of this meta-analysis was a change in the 6-minute walk distance (6MWD). In addition, peak oxygen uptake (PeakVO₂), resting pulmonary arterial systolic pressure (PASP_rest), resting heart rate (HR_rest), peak exercise heart rate (HR_peak), oxygen uptake anaerobic threshold (VO₂ at AT), maximum workload and quality of life (QoL) were also assessed.

Results

A total of 651 patients in 17 studies were included. A meta-analysis showed that exercise training was associated with significant improvement in the 6MWD [weighted mean difference (WMD): 64.75 m (95% CI: 53.19–76.31 m, P<0.001)], peakVO₂ [WMD: 1.78 mL/min/kg (95% CI: 1.27–2.29 mL/min/kg, P<0.001)], HR_peak [WMD: 11.07 beats/min (95% CI: 8.04–14.11 beats/min, P<0.001)] and QoL measured by SF-36 questionnaire subscale scores. Furthermore, exercise training is well tolerated, and no major adverse event occurred related to exercise training.

Conclusions

Exercise training is associated with a significant improvement in exercise capacity, cardiorespiratory fitness and quality of life among patients with PH and proved to be safe for stable PH patients with optimization of medical therapy. However, more large-scale multicenter studies are needed to confirm the effectiveness and safety of exercise training in patients with PH.

Cardiopulmonary exercise test indices of respiratory buffering before and after aerobic exercise training in women with pulmonary hypertension: Differentiation by magnitudes of change in six-minute walk test performance

While aerobic exercise training (AET) has generally been shown to improve 6-min walk test (6MWT) distance (6MWD) in patients with pulmonary hypertension (PH), a substantial number of patients appear to adapt differently, with minimal or even negative changes in 6MWT distance being reported.

PURPOSE

To compare post-aerobic exercise training adaptations in cardiorespiratory functional capacity across three groups of patients with PH: those with high (HI), low (LI) and negative (NEG) post-training increases in 6MWD.

METHODS

Participants were 25 females (age 54 ± 11 years; BMI 31 ± 7 kg/m²) who completed a vigorous, 10-week, thrice weekly, supervised treadmill walking exercise program. Cardiopulmonary exercise tests (CPET) and 6MWT were completed before and after training. Ten of the 25 participants were classified as HI (range = 47-143 m), 11 were classified as LI (range = 4-37 m) and 4 were classified as NEG (range = -17 to -53 m).

RESULTS

Peak CPET duration, WR and time to anaerobic threshold (AT) were significantly higher (p < 0.05) after training in both the LI and HI groups but not in the NEG group. There was a significant improvement in VE/VCO₂ (p = 0.042), PETCO₂ (p = 0.011) and TV (p = 0.050) in the HI group after training, but not in the NEG or LI group.

CONCLUSION

These findings suggest that sustained ventilatory inefficiency and restricted respiratory buffering may mediate exercise intolerance and impede the ability to adapt to exercise training in some patients with PH.

[A systematic review as a method of gathering scientific evidence into clinical guidelines: CHEST-2019 guideline for the therapy pulmonary arterial hypertension in adults]

The updated fourth version of the CHEST guideline presents the evidence base and treatment algorithm for pulmonary arterial hypertension in adults. The CHEST approach to creating clinical guidelines differs from the European one (ESC/ERS) and, in fact, consists in a systematic review of clinical trials and a sammary of their postulates.

Increasing quality of life in pulmonary arterial hypertension: is there a role for nutrition?

Pulmonary arterial hypertension (PAH) is a progressive disease primarily affecting the pulmonary vasculature and heart. PAH patients suffer from exercise intolerance and fatigue, negatively affecting their quality of life. This review summarizes current insights in the pathophysiological mechanisms underlying PAH. It zooms in on the potential involvement of nutritional status and micronutrient deficiencies on PAH exercise intolerance and fatigue, also summarizing the potential benefits of exercise and nutritional interventions. Pubmed/Medline, Scopus, and Web of Science were searched for publications on pathophysiological mechanisms of PAH negatively affecting physical activity potential and nutritional status, and for potential effects of interventions involving exercise or nutritional measures known to improve exercise intolerance. Pathophysiological processes that contribute to exercise intolerance and impaired quality of life of PAH patients include right ventricular dysfunction, inflammation, skeletal muscle alterations, and dysfunctional energy metabolism. PAH-related nutritional deficiencies and metabolic alterations have been linked to fatigue, exercise intolerance, and endothelial dysfunction. Available evidence suggests that exercise interventions can be effective in PAH patients to improve exercise tolerance and decrease fatigue. By contrast, knowledge on the prevalence of micronutrient deficiencies and the possible effects of nutritional interventions in PAH patients is limited. Although data on nutritional status and micronutrient deficiencies in PAH are scarce, the available knowledge, including that from adjacent fields, suggests that nutritional intervention to correct deficiencies and metabolic alterations may contribute to a reduction of disease burden.

Pulmonary hypertension and exercise training: a synopsis on the more recent evidences

The benefits of exercise training in virtually all humans, including those with a clinically stable chronic disease are numerous. The potential value lies in the fact that functional capacity is oftentimes significantly compromised. Exercise training not only play a role in reversing some of the pathophysiologic processes associated with chronic diseases but also improves clinical trajectory. Given the significant pathologic consequences associated with pulmonary hypertension and its implications for deteriorating right ventricular function as well as the perceived potential for a precipitous and possibly critical drop in cardiac output during periods of physical exertion, exercise training was historically not recommended for these patients. More recently, a promising body of literature demonstrating the safety and efficacy of exercise training (with benefit on exercise capacity, peak oxygen consumption and quality of life) in pulmonary hypertension patients has emerged, but the conclusion about the effects of exercise training were non-exhaustive and therefore there is still a lack of knowledge regarding exercise training for these patients. Thus, we aim to ascertain the current effectiveness of exercise rehabilitation for pulmonary hypertension by performing a brief overview on the latest currently available evidences in such an "at a glance" synopsis addressed to summarize/quantify the more recent existing body of literature. KEY MESSAGES Exercise training was historically not recommended in pulmonary hypertension. Recently, exercise training safety-efficacy in pulmonary hypertension has emerged. Exercise training should be recommended in addition to optimal medical therapy.

The effect of body mass index and physical activity on hypertension among Chinese middle-aged and older population

Few studies have been conducted to explore the independent and combined associations of body mass index (BMI) and physical activity with risk of hypertension in Chinese population. A cross-sectional study of 5291 individuals (aged ≥ 40 years) selected using multi-stage sampling method was conducted from October 2013 to December 2015. In the present analysis, 55.64% of the participants were women, and the mean age of participants was 55.37 ± 10.56. Compared with individuals in normal group, the risks of hypertension were nearly double in overweight subjects (odds ratio [OR] 1.77, 95% confidence interval [CI] 1.53–2.05) and more than three times higher in obese subjects (3.23, 2.62–4.13). Multi-adjusted odds for hypertension associated with low, moderate, and high physical activity were 1.44 (1.17–1.86), 1.40 (1.09–1.79) and 1.000, respectively. In comparison with normal weight subjects who reported high levels of physical activity, subjects who reported both low levels of physical activity and obesity showed the highest risk of hypertension (5.89, 3.90–8.88). In conclusion, both elevated BMI and reduced physical activity appear to play an important role in the risk of hypertension among Chinese middle-aged and older population. The risk of hypertension associated with overweight and obesity can be reduced considerably by increased physical activity levels.

Randomised controlled trial examining the effect of an outpatient exercise training programme on haemodynamics and cardiac MR parameters of right ventricular function in patients with pulmonary arterial hypertension: the ExPAH study protocol

INTRODUCTION

Pulmonary hypertension (PH) is a potentially life-threatening condition characterised by elevated pulmonary artery pressure. Early stage PH patients are often asymptomatic. Disease progression is associated with impairment of right ventricular function and progressive dyspnoea. Current guidelines recommend exercise training (grade IIa, level B). However, many questions remain regarding the mechanisms of improvement, intensity of supervision and optimal frequency, duration and intensity of exercise. This study will assess the effect of an outpatient rehabilitation programme on haemodynamics and cardiac right ventricular function in patients with pulmonary arterial hypertension (PAH), a subgroup of PH.

METHODS AND ANALYSIS

This randomised controlled trial involves both a major urban tertiary and smaller regional hospital in New South Wales, Australia. The intervention will compare an outpatient rehabilitation programme with a control group (home exercise programme). Participants will be stable on oral PAH-specific therapy. The primary outcome measure will be right ventricular ejection fraction measured by cardiac MRI. Secondary outcomes will include haemodynamics measured by right heart catheterisation, endurance, functional capacity, health-related quality of life questionnaires and biomarkers of cardiac function and inflammation.

ETHICS APPROVAL AND DISSEMINATION

Ethical approval has been granted by St Vincent's Hospital, Sydney (HREC/14/SVH/341). Results of this study will be disseminated through presentation at scientific conferences and in scientific journals.

TRIAL REGISTRATION NUMBER

ACTRN12615001041549; pre-results.