Causal Associations with Arterial Stiffness and Sarcopenia: A Mendelian Randomization Analysis

Area of Science:

• Cardiovascular Health
• Gerontology
• Musculoskeletal Physiology

Background:

• Observational studies suggest a link between arterial stiffness (AS) and sarcopenia (SAR).
• The precise causal relationship between AS and SAR remains incompletely understood.
• Understanding this link is crucial for addressing age-related decline in both vascular and muscle health.

Purpose of the Study:

• To investigate the potential causal relationship between arterial stiffness (AS) and sarcopenia (SAR).
• To explore the directionality of the causal connection using Mendelian randomization (MR).
• To identify specific indicators of AS and SAR involved in this bidirectional relationship.

Main Methods:

• Mendelian randomization (MR) analysis utilizing Genome-Wide Association Studies (GWAS) data.
• Examined AS indicators: pulse wave arterial stiffness index (PWASI) and pulse wave peak-to-peak time (PPT).
• Assessed SAR indicators: low hand grip strength (LHGS), usual walking pace (UWP), moderate-to-vigorous physical activity (MVPA), and unassisted mobility.

Main Results:

• A bidirectional causal relationship was identified between arterial stiffness and sarcopenia.
• Increased arterial stiffness (PWASI) was associated with reduced usual walking pace (UWP).
• Lower muscle strength (LHGS) was causally linked to altered pulse wave peak-to-peak time (PPT), and UWP influenced both PWASI and PPT.

Conclusions:

• Arterial stiffness and sarcopenia exhibit a reciprocal causal relationship.
• Elevated arterial stiffness may subtly impair motor function, while reduced muscle strength can contribute to increased arterial stiffness.
• These findings offer new insights into the interconnected mechanisms underlying vascular and muscle pathophysiology.