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Q. What percentage of college woman, according to a recent survey reported at the annual meeting of the American Urogyncecologic Society, described symptoms of urinary dysfunction?

A. 40

Introduction

        Theresa Spitznagle, a researcher, reported at the most recent meeting of the American Urogyncecologic society that she surveyed a group of 108 female nulliparous undergraduate and graduate students with a 56 item instrument that asked about weekly activity levels and urologic symptoms. The student sample included soccer players, physical therapy students and occupational therapy students. The results were as follows:
• Percentage that reported one or more symptoms of urinary dysfunction = 40%
• Percentage that reported stress incontinence = 35%
• Percentage that reported urgency = 34%
• Percentage that reported urge incontinence = 30%
• Percentage that reported frequency = 20%

These results are startling, to say the least. Stress incontinence is urinary loss associated with a cough, sneeze or laugh. Urge incontinence is a strong need to urinate with actual urine loss. Urgency is a strong need to urinate with a feeling that leakage will occur and frequency is defined as urination more than 6 times per day. The level of incontinence (in which actual involuntary urine loss occurs) is known to affect an estimated 10 million people in the United States, but this condition is almost always thought to occur in the elderly. The fact that 30 – 35% of college woman are reporting incontinence is evidence that the problem is almost certainly more widespread than previously thought. What follows is a brief overview of  bladder basics

Bladder Basics

1. The Muscles of Micturation

The bladder has three muscles that work together in the process of micturation. These muscles are the detrussor muscle, internal sphincter and external sphincter.
a Detrussor muscle – this muscle occurs in the body of the bladder. It is a smooth muscle, which, when contracted, causes the body of the bladder to contract (thus squeezing or expelling the urine) It should be noted that the abdominal muscles can and often do play a role in micturation as well. Contraction of abdominal muscles can increase intra-abdominal pressure. Increased intra-abdominal pressure in turn can help push urine out of the bladder and thus aid in emptying the bladder.
b Internal sphincter – this is smooth circular muscle found in the neck of the bladder. It is a continuation of the detrussor muscle. In females it forms the entire urethra and is about 2.5 – 3.5 cm in length. In males it forms the posterior urethra only. In males the entire urethra is about 16.5 – 18. 5 cm. in length. When the body of the bladder is relaxed, the internal sphincter is closed, thus holding the urine in- i.e. it functions as a sphincter preventing the outflow of urine. When the detrussor muscle contracts , the internal sphincter relaxes, allowing urine to flow out
c External sphincter- this is circular striated muscle (remember striated muscle is under voluntary control, whereas smooth muscle is involuntary). The external sphincter wraps around the internal sphincter rather like a ring around a finger. It acts as a type of final regulator of urinary outflow. When contracted it squeezes shut the internal sphincter thus preventing the outflow of urine, even if the internal sphincter is relaxed. Because it is under voluntary control it allows an individual to override the normal reflex of micturation and to hold urine in, even if there is the urge to void because of increased urinary volume in the bladder. In normal situations both the internal and external sphincter need to be relaxed to allow for the outflow of urine.

2. Nerve Innervation of the Bladder Muscles

The parasympathetic and sympathetic divisions of the autonomic nervous system both play a role in bladder and sphincter innervation.

a .detrussor muscle – contains

1 acetylcholine receptors (parasympathetic system) which when stimulated cause muscle contraction- thus resulting in expulsion of urine and
2 beta adrenergic receptors (sympathetic receptors) which when stimulated allow for muscle relaxation, thus allowing the bladder to fill up with urine.

b. internal sphincter muscle- contains

1 alpha adrenergic receptors which when stimulated cause contraction of the sphincter, thus help to contain urine

c external sphincter- contains

1 acetylcholine receptors (under voluntary control from higher centers)- can contract or relax the muscle

3. Micturation

As the bladder fills with urine the detrussor muscle relaxes (in order to allow the increasing volume of urine to be accommodated and stored). However, when the bladder reaches a certain volume (and, therefore, a certain pressure), the micturation reflex sets in and the detrussor muscle contracts while simultaneously the internal sphincter relaxes and the urine is voided. This is an involuntary spinal cord reflex, hence there is no conscious control over the process and the bladder empties as it fills. This reflex is all that is present in infants. At age 2- 3 though, two events occur that allows for control of micturation. 1. Higher cortical centers become involved in the overall process and 2. the external sphincter matures, so that it too can play a role in micturation. As the higher cortical centers mature, an individual becomes aware of a sense of bladder fullness, which creates an urge to void. At this point one can either initiate detrussor contraction, and internal and external sphincter relaxation, allowing urination to occur, or one can override this sensation, inhibiting detrussor contraction, and increasing internal and external sphincter contraction, thus holding the urine in.

Types of Incontinence
1 Urge Incontinence- this is the most common of all types of incontinence, it accounts for about 65% of all cases. In these instances there is an uninhibited contraction of the bladder resulting in a leakage of urine, even though the internal and external sphincter may be contracted to oppose the outflow of urine. In a sense, the detrussor muscle works against the sphincter muscles and if the pressure of contraction of the detrussor muscle exceeds the pressure of contraction of the sphincter muscles then leakage occurs. The signs and symptoms are a sudden urge to urinate and if one is unable to void immediately, a leakage of urine. This type of incontinence can occur secondary to bladder stones, cystitis, neoplasms, or because of decreased cortical inhibition as might occur in cases of dementia.

The pharmacological treatment approach is to try override the contraction of the
detrussor muscle by giving a bladder relaxant. Since cholinergic stimulation
causes bladder contraction, the drug of choice would be an anticholinergic drug such
as Ditropan or Pro-Banthine or Bentyl or Urispas.

2 Stress Incontinence- this occurs more frequently in females. Increased intra-abdominal pressure (which in turn increases the pressure in the body of the bladder) leads to the leakage of of small to moderate amounts of urine. It occurs secondary to childbirth, estrogen deficiency, urethral weakness or post prostatectomy. The signs and symptoms are small to moderate amounts of urine loss with sneezing, coughing, laughing or in some cases, standing (note, all activities that can increase intra-abdominal pressure). In this case the best approach is to try to strengthen the sphincter muscles and muscles surrounding the sphincters, thus countering the increased intra-abdominal pressures that are pushing down and causing urine to leak out. The regular use of pelvic muscle exercises (Kegel exercises) are useful. Pharmacologically, you can increase sphincter resistance by giving alpha adrenergic agents, such as Sudafed, or Ornade. Or, you can increase blood flow to periurethral tissues, thus increasing the strength of urethral muscles, by giving conjugated estrogens.

3. Overflow Incontinence – this occurs because neurogenic factors allow for the bladder to  become overextended. The neurogenic factors are such that no urge to void is sensed, the individual is unaware that the bladder is filling up. Subsequently, it fills up with so much urine that the pressure increases in the bladder and urine leaks passed the sphincters. The signs and symptoms are: no urge to urinate and small amounts of leakage. In this case the pharmacological approach is to periodically stimulate the detrussor muscle to contract and to empty the bladder before it becomes so full that the urine leaks out. Hence, a cholinergic drug, such as Urecholine, is indicated. Or, conversely, get the urethra to relax and allow the bladder to empty by use of an alpha adrenergic blocking agent such Minipress.

Incontinence, as indicatd by the study quoted at the beginning of this piece, is a pervasive problem. It is important to know the different types of incontinence because the treatment for each type can vary. Accurate assessment is essential to appropriate treatment. For example, in one type of incontinence (overflow) a cholinergic is appropriate, whereas in another type (urge) an anticholinergic drug is appropriate. The following table is a guide to aid in the correct identification and treatment of incontinence

Kenneth Zwolski RN, EdD, CS

Resources

RxList (a good source to look up the drugs mentioned above)

National Association for Continence  (this site contains facts about incontinence, FAQ's about incontinence and more)