Structural basis of geriatric voiding dysfunction. II. Aging detrusor: normal versus impaired contractility

Area of Science:

• Urology
• Gerontology
• Cell Biology

Background:

• Geriatric voiding dysfunction lacks structural norm data for the aging detrusor.
• Understanding detrusor aging is crucial for addressing bladder dysfunction in the elderly.

Purpose of the Study:

• To identify structural correlates of urodynamically defined vesical function abnormalities in elderly subjects.
• To characterize the ultrastructural features of the aging detrusor.

Main Methods:

• Electron microscopy of detrusor biopsies from 35 elderly subjects.
• Independent and blinded urodynamic grouping and ultrastructural analysis.
• Correlation of structural patterns with detrusor contractility and symptoms.

Main Results:

• A 'dense band pattern' was identified, characterized by dense bands on sarcolemma and depleted caveolae.
• This pattern was associated with normal detrusor function in continent, symptom-free individuals.
• Superimposed muscle cell and axon degeneration correlated with impaired detrusor contractility.

Conclusions:

• The 'dense band pattern' likely represents the structural norm of the aging detrusor.
• Aging may involve detrusor muscle cell de-differentiation, potentially affecting ion exchange via caveolae depletion.
• Degeneration of muscle cells and axons is linked to impaired contractility in the aging detrusor.