Pathophysiological Link between Muscle Atrophy and Hypertension in Spinal Cord Injury Patients

Abstract

Spinal cord injury (SCI) is a catastrophic neurological condition that results in varying degrees of motor, sensory, and autonomic impairment below the level of injury. Beyond the immediate loss of motor function, one of the most significant long-term consequences of SCI is rapid and progressive skeletal muscle atrophy, driven by denervation, reduced mechanical loading, and altered metabolic signaling. Muscle mass can decline by nearly 30–50% within the first few months after injury, leading to profound reductions in strength, physical function, and overall metabolic health.

Growing evidence supports a bidirectional relationship between muscle atrophy and hypertension in SCI. Loss of metabolically active muscle reduces insulin sensitivity, myokine secretion, and peripheral vascular capacity, thereby promoting inflammation, arterial stiffness, and elevated blood pressure. Conversely, chronic and episodic hypertension impairs skeletal muscle microcirculation and endothelial function, potentially exacerbating muscle wasting and limiting rehabilitation outcomes. These processes are further amplified by insulin resistance, oxidative stress, autonomic imbalance, and renal mechanisms, creating a vicious cycle of neuromuscular and cardiovascular deterioration.

This review synthesizes current evidence on the mechanistic links between skeletal muscle atrophy and hypertension following SCI, highlighting the central role of muscle as both a structural and endocrine organ in cardiovascular regulation. Understanding this integrated pathophysiology has important clinical implications, underscoring the need for muscle-centered, multidisciplinary rehabilitation strategies—including resistance training, neuromuscular electrical stimulation, nutritional optimization, and individualized blood pressure management—to mitigate long-term cardiovascular risk, improve functional independence, and enhance quality of life in people living with SCI.