A more effective alternative to the 6-minute walk test for the assessment of functional capacity in patients with pulmonary hypertension

Prediction of peak oxygen consumption using cardiorespiratory parameters from warmup and submaximal stage of treadmill cardiopulmonary exercise test

This study investigates the quality of peak oxygen consumption (VO2peak) prediction based on cardiac and respiratory parameters calculated from warmup and submaximal stages of treadmill cardiopulmonary exercise test (CPET) using machine learning (ML) techniques and assesses the importance of respiratory parameters for the prediction outcome. The database consists of the following parameters: heart rate (HR), respiratory rate (RespRate), pulmonary ventilation (VE), oxygen consumption (VO2) and carbon dioxide production (VCO2) obtained from 369 treadmill CPETs. Combinations of features calculated based on the HR, VE and RespRate time-series from different stages of CPET were used to create 11 datasets for VO2peak prediction. Thirteen ML algorithms were employed, and model performances were evaluated using cross-validation with mean absolute percentage error (MAPE), R2 score, mean absolute error (MAE), and root mean squared error (RMSE) calculated after each iteration of the validation. The results demonstrated that incorporating respiratory-based features improves the prediction of VO2peak. The best results in terms of R2 score (0.47) and RMSE (5.78) were obtained for the dataset which included both cardiac- and respiratory-based features from CPET up to 85% of age-predicted HRmax, while the best results in terms of MAPE (10.5%) and MAE (4.63) were obtained for the dataset containing cardiorespiratory features from the last 30 seconds of warmup. The study showed the potential of using ML models based on cardiorespiratory features from submaximal tests for prediction of VO2peak and highlights the importance of the monitoring of respiratory signals, enabling to include respiratory parameters into the analysis. Presented approach offers a feasible alternative to direct VO2peak measurement, especially when specialized equipment is limited or unavailable.

Leisure-time physical activity, occupational physical activity and the physical activity paradox in healthcare workers: A systematic overview of the literature

BACKGROUND

Physical activity positively influences cardiovascular health. Results from male-dominated physically active occupations suggest that a high level of occupational physical activity may be detrimental to cardiovascular health. This observation is referred to as the physical activity paradox. Whether this phenomenon can also be observed in female-dominated occupations remains unknown.

OBJECTIVE

We aimed to provide an overview of (1) leisure-time and occupational physical activity in healthcare workers. Therefore, we reviewed studies (2) to assess the relationship between the two physical activity domains and analyzed (3) their effects on cardiovascular health outcomes in relation to the paradox.

METHODS

Five databases (CINAHAL, PubMed, Scopus, Sportdiscus, Web of Science) were systematically searched. Both authors independently screened the titles, abstracts, and full texts and assessed the quality of the studies using the National Institutes of Health's quality assessment tool for observational cohort and cross-sectional studies. All studies that assessed leisure-time and occupational physical activity in healthcare workers were included. The two authors independently rated the risk of bias using the ROBINS-E tool. The body of evidence was evaluated using the GRADE approach.

RESULTS

The review included 17 studies that assessed the leisure-time and occupational physical activity of people working in healthcare, determined the relationship between the domains (n = 7) and/or examined their effects on the cardiovascular system (n = 5). Measurements for leisure-time and occupational physical activity varied between studies. Leisure-time physical activity typically ranged between low and high intensity, with a short duration (approx. 0.8-1.5 h). Occupational physical activity was typically performed at light to moderate intensity with a very long duration (approx. 0.5-3 h). Moreover, leisure-time and occupational physical activity were almost negatively related. The few studies investigating effects on cardiovascular parameters revealed a rather unfavorable effect of occupational physical activity, while leisure-time physical activity was beneficial. The study quality was rated as fair and the risk of bias was moderate to high. The body of evidence was low.

CONCLUSIONS

This review confirmed that leisure-time and occupational physical activity of healthcare workers are opposed in their duration and intensity. Moreover, leisure-time and occupational physical activity seem to be negatively related and should be analyzed according to their relation to each other in specific occupations. Furthermore, results support the relationship between the paradox and cardiovascular parameters.

REGISTRATION

Preregistered on PROSPERO (CRD42021254572). Date of registration on PROSPERO: 19 May 2021.

TWEETABLE ABSTRACT

Does occupational physical activity adversely affect the cardiovascular health of healthcare workers in comparison to leisure-time physical activity?

Cardiovascular complications in patients with interstitial lung disease and their correlation with 6-minute walk test and spirometry: A single-center study

Introduction

Pulmonary hypertension and other cardiac complications occur frequently due to chronic hypoxia induced by interstitial lung diseases (ILD) or due to connective tissue disorder itself. Two-dimensional (2D) echocardiography is ideal for identifying abnormalities at a given time. In this study, we tried to detect cardiovascular complications in patients with ILD using 2D echocardiography and correlate them with a 6-minute walk test (6 MWT) and spirometry.

Materials and Methods

This study was carried out for 18 months including 100 consecutive cases of ILD. The diagnosis was made using the latest criteria as per the disease and high-resolution computed tomography (HRCT) thorax. All patients were evaluated with 2D echocardiography, 6 MWT, and spirometry along with routine investigations. Their results were analyzed using STATA 15.1 software.

Result

Cardiovascular involvement was detected in 68% of cases. Pulmonary hypertension predominated with a prevalence of 50%. In spirometry, mean Forced expiratory volume in first second (FEV₁)and Forced vital capacity (FVC) were found to be 54.96 (L) and 53.49 (L), respectively, with a predominant restrictive pattern (89%). There was a significant correlation between baseline saturation of oxygen (SpO₂) and pulmonary arterial systolic pressure (PASP) with a P value of <0.05. Baseline SpO₂ and distance covered in 6 MWT had a significant correlation (P = 0.014).

Conclusion

A baseline or nighttime hypoxia is responsible for developing PAH. Pulmonary arterial hypertension should be suspected in patients unable to perform 6 MWT or having low baseline SpO₂. A routine follow-up with a 6 MWT and baseline SpO₂ should be performed in each visit to identify early deterioration of the disease.