Urological abnormalities in young women with severe constipation

Area of Science:

• Gastroenterology
• Urology
• Physiology

Background:

• Severe constipation is a common issue affecting quality of life.
• Understanding the physiological underpinnings of constipation is crucial for effective treatment.
• Previous research suggests potential links between anorectal and lower urinary tract function.

Purpose of the Study:

• To investigate anorectal and urodynamic function in young women with severe constipation.
• To compare these functions with healthy controls.
• To identify potential physiological mechanisms contributing to severe constipation.

Main Methods:

• Anorectal manometry and urodynamic studies were performed on 10 young women with severe constipation and 10 age-matched controls.
• Electromyography (EMG) of the external anal sphincter (EAS) was used to assess sphincter function during defecation attempts.
• Rectal and bladder volumes and pressures were measured to assess sensory thresholds and capacity.

Main Results:

• Constipated patients had significantly higher volumes to provoke defecation (200ml vs 110ml) and micturition (560ml vs 295ml) compared to controls.
• Maximum tolerable rectal volume (380ml vs 290ml) and bladder capacity (720ml vs 540ml) were significantly increased in constipated individuals.
• EMG studies revealed impaired EAS relaxation in all constipated patients, with 80% exhibiting EAS contraction during straining, indicating functional outlet obstruction. Urodynamic studies showed normal urinary flow and pressures.

Conclusions:

• Young women with severe constipation exhibit increased rectal and bladder capacity with reduced sensory perception.
• Impaired external anal sphincter (EAS) relaxation and paradoxical contraction contribute to functional outlet obstruction in these patients.
• Despite anorectal dysfunction, urinary tract function remains largely unaffected, suggesting specific mechanisms for constipation-related bladder changes.