Incontinence - Causes
Stress incontinence is the most common type of leakage encountered and is most associated with bladder leakage. Stress incontinence is the loss of urine that occurs with any maneuver that increases intra-abdominal pressure, such as coughing, sneezing, lifting, laughing, intercourse, or changing position.
This typically occurs in women that experience loss of support in the anterior vaginal wall leading to dropping of the bladder neck and urethra during increases in abdominal pressure. Most investigators feel that the descent of the bladder neck and urethra out of the normal intra-abdominal position into the pelvis prevents closure of these structures during times when pressure is exerted on the bladder body. Some feel that the change in the angle of the bladder neck and urethra are responsible for the leakage. Stress incontinence can occur in men as well, but is most often seen following trans-urethral prostate surgery or surgery for prostate cancer.
Leakage that occurs when there is a sudden uncontrollable need to urinate is urge incontinence. This most often occurs in those people with spinal cord injuries, multiple sclerosis, strokes, or diseases of the spinal cord.
This may occur in male patients with an obstructing prostate or in women with loss of estrogen effects to the vaginal wall, bladder and urethra. The bladder muscle in many of these patients is overactive and usually provides very little warning to the patient that urination is eminent.
Occasionally, in elderly patients, this bladder overactivity is accompanied by decreased bladder contractions, leaving these patients with incompletely emptied bladders. This syndrome is called detrusor hyperactivity with impaired contractility.
Overflow incontinence occurs when the bladder is inefficiently emptied, leaving large amounts of urine in the bladder. As the volume increases, the resistance provided by the bladder, neck and urethra may be overcome, and urine loss may occur. This pattern is common in diabetics, male patients with enlarged prostates, urethral structures and in some patients with spinal cord injuries. In some cases this may be caused by medications taken for other conditions.
Functional incontinence is common in disabled or demented patients and is the most common type of incontinence in the nursing home setting. Patients with functional incontinence have normal bladder activity but are unable to respond to this signal, due to immobility or impaired mental functioning. As a consequence, they become incontinent unless they are prompted or asked to void on a schedule.