How pulmonary arterial hypertension affects lean muscle mass

Understanding the Effects of Pulmonary Arterial Hypertension on Lean Muscle Mass

This study will see if PAH is linked to muscle loss and whether that loss affects activity, quality of life, and hospital visits in people with PAH.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 150 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: University of Pennsylvania (Academic / other)
• Locations: 1 site (Philadelphia, Pennsylvania)
• Trial ID: NCT07132788 on ClinicalTrials.gov

What this trial studies

This observational interventional protocol enrolls adults with Group 1 PAH and collects body-composition and functional measures at baseline and Week 12. Participants undergo vitals, blood draws, questionnaires, physical performance tests (SPPB, 6-minute walk, grip strength), and chest CT to measure cardiac and regional fat. In a subset, a physical therapist applies a wireless NIRS device (PortaMon) to measure muscle oxygenation before and after standardized exercises to explore muscle physiology. Outcomes include changes in lean muscle mass, daily physical activity, quality-of-life measures, and hospitalizations.

Who should consider this trial

Good fit: Adults with Group 1 PAH (idiopathic, heritable, drug/toxin-induced, or associated forms) diagnosed within 6 months or on stable PAH therapy for at least 3 months, with hemodynamic confirmation by right heart catheterization (mPAP > 20 mmHg, PAWP or LVEDP ≤ 15 mmHg, and PVR > 2 Wood units) are ideal candidates.

Not a fit: People with non–Group 1 pulmonary hypertension, significant obstructive ventilatory defects (FEV1/FVC ≤ 5th percentile and FEV1 z-score < -2.5), or those unable to attend in-person visits are unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, identifying factors such as cardiac fat linked to muscle loss could point to treatments that improve physical function and quality of life for people with PAH.

How similar studies have performed: Prior studies have shown muscle weakness and reduced exercise capacity in PAH, but combining CT-measured cardiac fat with NIRS muscle-oxygenation measures to link epicardial fat to muscle loss is a relatively novel approach.

Eligibility criteria

Inclusion Criteria:

* Signed informed consent prior to initiation of any study mandated procedure.
* Diagnosis of PAH belonging to one of the following subgroups of Group 1 PH according to the updated clinical classification \[Humbert 2022\]

  * Idiopathic (IPAH)
  * Heritable (HPAH)
  * Drugs or toxins induced
  * Associated (APAH) with one of the following:

    * Connective tissue disease;
    * Human immunodeficiency virus (HIV) infection;
    * Congenital heart disease; or
    * Portopulmonary hypertension
* Diagnosis of PAH within 6 months of enrollment or diagnosis of PAH and on stable therapy for 3 months prior to enrollment
* Documented hemodynamic diagnosis of PAH by right heart catheterization (RHC), prior to enrollment showing:

  * mPAP \> 20 mmHg; and
  * PAWP or LVEDP ≤ 15 mmHg
  * PVR \> 2 Wood units

Exclusion Criteria:

* Prior to enrollment, evidence of moderately severe obstructive ventilator defect with:

  * FEV1/FVC ≤ 5th percentile; and
  * FEV1 z-score \< 2.5
* Prior to enrollment, evidence of severe restrictive defect with

  * TLC \< 5th percentile
  * FEV1 z-score \< 4
* Prior to enrollment, hospitalization (within 1 week) for decompensated right heart failure
* More than moderate aortic or mitral valve disease
* LVEF \< 40% within 1 year of screening
* Pregnancy

Where this trial is running

Philadelphia, Pennsylvania

• University of Pennsylvania Hospital — Philadelphia, Pennsylvania, United States (Recruiting)

Study contacts

• Principal investigator: Nadine Al-Naamani, MD — University of Pennsylvania
• Study coordinator: Rebecca Gallagher

Conditions Pulmonary Hypertension; pulmonary hypertension; body composition