Physical Activity and Its Association with Traditional Outcome Measures in Pulmonary Arterial Hypertension

Evaluating the technical use of a Fitbit during an intervention for patients with pulmonary arterial hypertension with quality of life as primary endpoint: Lessons learned from the UPHILL study

This article examines technical use of Fitbit during an intervention for pulmonary hypertension (PAH)-patients. Technical issues with the device led to data being unavailable(37.5%). During intervention objective daily physical activity (DPA) decreased and subjective DPA increased. This emphasizes that an assessment of DPA in PAH requires incorporating both objective and subjective measurements.

Digital measurement of mobility in pulmonary arterial hypertension: A structured review of an emerging area

This review examined literature that has examined mobility in pulmonary arterial hypertension (PAH) using digital technology. Specifically, the review focussed on: (a) digital mobility measurement in PAH; (b) commonly reported mobility outcomes in PAH; (c) PAH specific impact on mobility outcomes; and (d) recommendations concerning protocols for mobility measurement in PAH. PubMed, Scopus, and Medline databases were searched. Two independent reviewers screened articles that described objective measurement of mobility in PAH using digital technology. Twenty-one articles were screened, and 16 articles met the inclusion/exclusion criteria and were reviewed. Current methodologies for mobility measurement in PAH with digital technologies are discussed. In brief, the reviewed evidence demonstrated that there is a lack of standardisation across studies for instrumentation, outcomes, and interpretation in PAH. The validity and reliability of digital approaches were insufficiently reported in all studies. Future research is required to standardise digital mobility measurement and characterise mobility impairments in PAH across clinical and real-world settings. The reviewed evidence suggests that digital mobility outcomes may be useful clinical measures and may be impaired in PAH, but further research is required to accurately and robustly establish findings. Recommendations are provided for future studies that encompass comprehensive reporting, validation, and measurement.

Pulmonary Hypertension: A Contemporary Review

Major advances in pulmonary arterial hypertension, pulmonary hypertension (PH) associated with lung disease, and chronic thromboembolic PH cast new light on the pathogenetic mechanisms, epidemiology, diagnostic approach, and therapeutic armamentarium for pulmonary vascular disease. Here, we summarize key basic, translational, and clinical PH reports, emphasizing findings that build on current state-of-the-art research. This review includes cutting-edge progress in translational pulmonary vascular biology, with a guide to the diagnosis of patients in clinical practice, incorporating recent PH definition revisions that continue emphasis on early detection of disease. PH management is reviewed including an overview of the evolving considerations for the approach to treatment of PH in patients with cardiopulmonary comorbidities, as well as a discussion of the groundbreaking sotatercept data for the treatment of pulmonary arterial hypertension.

Peak steps: Capacity for activity improves after adding approved therapy in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) patients have low activity. Activity intensity or duration could be a measure of clinical status or improvement. We aimed to determine whether standard or novel actigraphy measures could detect increases in activity after adding therapy. This was a prospective, single-center observational study evaluating activity after adding therapy in Group 1 PAH; we also report a validation cohort. For our study, two different accelerometers were used, a wrist (ActiGraph) and chest (MC10) device. Patients were analyzed in two groups, Treatment Intensification (TI, adding therapy) or Stable. Both groups had baseline monitoring periods of 7 days; the TI group had follow-up at 3 months, while Stables had follow-up within 4 weeks to assess stability. Activity time and steps were reported from both devices' proprietary algorithms. In ActiGraph only, steps in 1-min intervals throughout the day were ranked (not necessarily contiguous). Average values for each week were calculated and compared using nonparametric testing. Thirty patients had paired data (11 Stable and 19 TI). There was no between-group difference at baseline; we did not observe therapy-associated changes on average daily steps or activity time/intensity. The top 5 min of steps (capacity) increased after adding therapy; there was no difference in the stable group. This key finding was validated in a previously reported randomized trial studying a behavioral intervention to increase exercise. Total daily activity metrics are influenced by both disease and non-disease factors, making therapy-associated change difficult to detect. Peak minute steps were a treatment-responsive marker in both a pharmacologic and training intervention.

"It's that invisible illness": Patient and clinician perspectives on outcomes in pulmonary arterial hypertension treatment

Knowledge of what outcomes are most meaningful to pulmonary arterial hypertension (PAH) stakeholders is limited. In this qualitative study, patients and clinicians endorsed personalized physical activity, symptoms, and psychosocial well-being as key outcomes to assess PAH treatment response, yet few are routinely measured in PAH clinical trials.

Cardiac Effort to Compare Clinic and Remote 6-Minute Walk Testing in Pulmonary Arterial Hypertension

BACKGROUND

The SARS-CoV-2 pandemic has limited objective physiologic assessments. A standardized remote alternative is not currently available. "Cardiac effort" (CE), that is, the total number of heart beats divided by the 6-min walk test (6MWT) distance (beats/m), has improved reproducibility in the 6MWT and correlated with right ventricular function in pulmonary arterial hypertension.

RESEARCH QUESTION

Can a chest-based accelerometer estimate 6MWT distance remotely? Is remote cardiac effort more reproducible than 6MWT distance when compared with clinic assessment?

STUDY DESIGN AND METHODS

This was a single-center, prospective observational study, with institutional review board approval, completed between October 2020 and April 2021. Group 1 subjects with pulmonary arterial hypertension, receiving stable therapy for > 90 days, completed four to six total 6MWTs during a 2-week period to assess reproducibility. The first and last 6MWTs were performed in the clinic; two to four remote 6MWTs were completed at each participant's discretion. Masks were not worn. BioStamp nPoint sensors (MC10) were worn on the chest to measure heart rate and accelerometry. Two blinded readers counted laps, using accelerometry data obtained on the clinic or user-defined course. Averages of clinic variables and remote variables were used for Wilcoxon matched-pairs signed rank tests, Bland-Altman plots, or Spearman correlation coefficients.

RESULTS

Estimated 6MWT distance, using the MC10, correlated strongly with directly measured 6MWT distance (r = 0.99; P < .0001; in 20 subjects). Remote 6MWT distances were shorter than clinic 6MWT distances: 405 m (330-464 m) vs 389 m (312-430 m) (P = .002). There was no difference between in-clinic and remote CE: 1.75 beats/m (1.48-2.20 beats/m) vs 1.86 beats/m (1.57-2.14 beats/m) (P = .14).

INTERPRETATION

Remote 6MWT was feasible on a user-defined course; 6MWT distance was shorter than clinic distance. CE calculated by chest heart rate and accelerometer-estimated distance provides a reproducible remote assessment of exercise tolerance, comparable to the clinic-measured value.