A geriatric patient with chronic kidney disease experiences progressive muscle weakness, diagnosed as sarcopenia. Why does reduced kidney function accelerate sarcopenia in this patient?

💡 Explanation

Impaired kidney function leads to reduced ammonia excretion. Because ammonia is neurotoxic, the body buffers it by converting muscle protein into glutamine, accelerating muscle breakdown via proteolysis; therefore, sarcopenia progresses in kidney disease, rather than because of insulin sensitivity, erythropoietin, or vitamin D effects.

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