Functional Daytime Urinary Incontinence

Definition and Introduction

Daytime incontinence is often considered one of the most embarrassing problems a child can face in childhood. It can be quite vexing to both the child and family, especially if it occurs particularly in a sporadic fashion or with little or no warning. The child and family may feel “caught” by the wetting and have a sense of being helpless to prevent future occurrences.

The definition is valid after ruling out organic causes. This implies that a disorder of the bladder function is present resulting in involuntary passing of urine at an inappropriate place and time.

Conversely, organic (i.e., not functional) urinary incontinence can be caused, for instance, by malformation (structural factor) or a disorder of bladder innervation (neurogenic factor). Thus, organic incontinence is wetting due to congenital or anatomical anomalies.

The term functional implies that no organic dysfunction exists. The child must be at least five years old and wet at least once a month over a period of three months. If urinary incontinence Opens in new window or enuresis Opens in new window occurs less frequently than once a month, it is referred to as a symptom but not as a disorder. Frequent wetting is characterized by at least four episodes per week.

Subtypes

In functional daytime urinary incontinence, three common and several rare types can be differentiated. We begin by describing the three common types urge incontinence, voiding postponement, and dysfunctional voiding. These are each discussed briefly below.

1. Urge incontinence

Urinary incontinence with urgency is described as urge incontinence Opens in new window (overactive bladder). In most cases, it is due to genetic factors with an inherent dysfunction of the filling phase of the bladder.

The bladder contracts spontaneously during the filling phase, which often leads to urgency and frequent micturitions (up to 20 times a day) with small amounts of urine. These reactions are not adequately inhibited by the central nervous system. The child tries to suppress the urge by using holding maneuvers (e.g., pressing legs together, sitting on the heel, etc.).

2. Voiding postponement

Urinary incontinence in voiding postponement is an acquired disorder. It is characterized by postponing micturition habitually, so that wetting during daytime occurs despite holding maneuvers. The most important sign for this type is infrequent micturitions (less than 5 times a day).

Children postpone micturition in typical situations, e.g., at school, during play, or while watching TV. The longer the voiding postponement persists, the stronger the urgency gets. These children use similar holding maneuvers as those with urge incontinence. Finally, when micturition cannot be postponed any longer, wetting occurs.

3. Dysfunctional voiding

Dysfunctional voiding is defined by a lack of relaxation and paradox contraction of the urethral sphincter during micturition (i.e., it is a disorder of the emptying phase). It is an acquired coordinative dysfunction between detrusor and sphincter.

The sphincter contracts during micturition instead of relaxing. The detrusor, therefore, pushes against the activated sphincter in order to achieve emptying. Children with dysfunctional voiding cannot urinate spontaneously. They need to strain to initiate micturition. As a result, the stream of urine is interrupted.

When these main symptoms occur (straining, interrupted voiding), further assessment with uroflowmetry and EMG is indicated, as the risk of medical complications is the highest in this type of daytime urinary incontinence. (Chase, Austin, Hoebeke, & McKenna, 2010).

Rare types of daytime urinary incontinence include:

1. Stress incontinence

Stress incontinence Opens in new window is characterized by urine leakage during an increase of intra-abdominal pressure, e.g., when coughing or sneezing. Stress incontinence is rare in childhood but typical in adult women. The amounts of urine leakage are usually small.

2. Giggle incontinence

Giggle incontinence is characterized by complete bladder emptying while laughing. The amounts of urine are very large. This disorder is inherited.

3. Underactive bladder

Underactive bladder (formerly lazy bladder syndrome) represents a rare type of daytime urinary incontinence. The detrusor is decompensated sot that the bladder cannot spontaneously be emptied completely and high volumes of residual urine remain. Micturition is interrupted and abdominal pressure is needed to achieve bladder emptying.

4. Vaginal reflux

Vaginal reflux is a rare subtype in girls.

Natural History of Continence Control

Normal bladder control in a child requires several basic parts of the anatomy to be complete and normal. There must be an intact neural system. The coordination of voiding is mediated in the pontine micturition center of the brain stem.

External sphincter relaxation is synchronized to occur just prior to detrusor contraction. There must be normal and intact urinary system. These two components are sufficient to have a physiologically safe system. Healthy babies and pre-toilet-trained children, for example, store and void using just these two components without any consequences.

In addition to these two components, continence requires that there is a conscious perception of what are occurring during storage and voiding and an understanding of the social norms associated with continence. In a sense, every normal child already has the mechanism of continence but has to learn when and where it is appropriate to void.

Babies and pre-toilet-trained children store urine under low pressure until the volume reaches the bladder functional capacity at which point the external sphincter relaxes, the bladder neck opens, and the detrusor contracts. These actions occur in a synchronized sequence that is essentially reflexic. It is involuntary, and there is little social awareness as anyone who has ever been voided upon while changing a baby’s diaper can attest.

Adults in contrast perceive when their bladders are becoming full and have awareness typically long before the functional capacity is reached. They can then choose to voluntarily initiate the voiding process. Likewise they can inhibit or delay the voiding reflex for often extended periods of time until it is socially convenient to void.

The transition from the pattern of babies and incontinent children to the adult pattern passes through several phases. First, the child must be able to sense bladder fullness and link the sensation to a mental perception of fullness. This usually occurs around age 1–2 years. Next, the child must have awareness and perception of the external sphincter.

The earliest means of continence control is squeezing the external sphincter in response to a detrusor contraction. This may be an extension of voluntary control over the guarding reflex. It may be also at this period of time, around age 2–4 years, that avoidance maneuvers such as the Vincent’s curtsy Opens in new window can occur. This is the maneuver wherein a child tucks the heel under the perineum and sits on it. This action presses up against the perineum thereby tightening the pelvic muscles.

By age 3–5 years, most children have developed an adult pattern of voiding. They are aware of bladder fullness and perceive what that sensation means. They can inhibit the micturition reflex temporarily until it is socially appropriate and can initiate voiding even when bladder volume is less than the functional capacity.

By age 6 years, the vast majority of children (>75 %) have achieved daytime continence, and the majority are dry at night.

Children before they can be expected to void like adults, therefore, must be able to do the following. They must understand or want to understand the social norms of continence. Many of the problems we encounter in children struggling to achieve daytime relate to a failure to fully achieve these capabilities.

Differential Diagnoses and Comorbid Disorders

Children with daytime urinary incontinence have higher rates of somatic disorders than children with nocturnal enuresis only. Therefore, the assessment and treatment of the underlying organic disorder is especially important to avoid lasting kidney damage from recurring infections of the lower urinary tract.

The following causes of urinary incontinence can be differentiated:

1. structural (i.e., malformation and abnormalities of the urinary tract);
2. neurogenic (i.e., dysfunction of the innervations of the bladder); and
3. other physical diseases (i.e., diseases which result in an increased urine production, such as diabetes insipdidus or mellitus, or urinary tract infections).

1. Structural urinary incontinence

In structural urinary incontinence malformations of the urinary tract exist, which require urological or surgical assessment. Malformations include those of the kidneys (renal agenesis: the complete missing of a kidney; double kidneys, renal pelvis distension) or malformations of the ureter (e.g., megaureter — enlarged ureter).

Vesicoureteral reflux (VUR)—urine flowing back from the bladder through the ureter up to the kidneys—is a common differential diagnosis which can also be caused by increased bladder pressure (as in voiding postponement or dysfunctional voiding). In severe types of VUR, the renal pelvis is involved. In mild types, urinary tract infections can occur.

VUR must always be assessed radiographically and should be referred to pediatric urologists or nephrologists. Mild types are treated conservatively with an antibiotic prophylaxis (long-term antibiotics), severe types often require surgery.

The urethra can be affected by malformations such as posterior urethral valves, but a stenosis of the urethra has to be considered as well. Furthermore, abnormal outlets of the urethra have to be excluded in boys (hypopadias, epispadias).

2. Neurogenic urinary incontinence

In neurogenic urinary incontinence the innervation of the bladder is disturbed (e.g., in spina bifida occulta). Individuals with spina bifida, a malformation of the vertebral arches, can show neural deficits of the lower extremities as well as of the bladder.

Other rare neurogenic causes of incontinence are the tethered cord syndrome and tumors of the spinal cord. Therefore, the spine, asymmetries of the buttocks and lower extremities, reflex differences, and sensitivity deficits or the lower extremities should always be examined thoroughly.

3. Other disease

Urinary incontinence can rarely be due to other underlying diseases, such as diabetes mellitus or diabetes insipidus (lack of ADH). Another neurologic condition that can cause incontinence is sacral agenesis.

Comorbid Psychological Disorders

Children with daytime urinary incontinence have an increased rate of comorbid psychological disorders (von Gontard, Baeyens, et al., 2011). Joinsen, Heron, von Gontard, & ALSPAC team (2006) found increased rates for ADHD (24.8%), oppositional behavior (10.9%), and conduct problems (11.8%).

In an epidemiological study of 1.391 preschool children, von Gontard, Moritz, and colleagues (2011) found a specific association of daytime wetting and ADHD. However, the risk for ADHD was not increased in children with nocturnal enuresis only or fecal incontinence.

Children with urge incontinence have slightly increased psychological comordity rates. Of these children, 29–36% were affected by externalizing as well as internalizing disorders (von Gontard et al., 1999; Zink et al., 2008).

Children with voiding postponement showed comorbid psychological disorders more often (53–54%). Externalizing disorders are very typical — especially conduct problems with oppositional behavior.

Kuhn and colleagues (2009) compared children with voiding postponement to children with urge incontinence. Children with these types of daytime wetting had significantly more behavioral problems, assessed with the Child Behavior Checklist (CBCL; Achenbach, 1991), than nonwetting controls. Children with voiding postponement had more behavioral problems in general and were at a higher risk for externalizing behavioral disorders than children with urge incontinence.

Clinically, children with dysfunctional voiding can be differentiated into two groups:

1. children without any psychological disturbances and
2. children with a high degree of comorbid psychological disorders.

– Comorbid Soiling

The frequency of soiling Opens in new window is increased in children with daytime and nighttime wetting. According to von Gontard and Hollman (2004), 12% of children with enuresis/daytime urinary incontinence also suffer from fecal incontinence.

Children with daytime wetting are significantly more often affected by fecal incontinence Opens in new window than children with nocturnal enuresis (24.6% vs. 5.5%).

In a study by Kuhn et al. (2009), 41% of the children with daytime urinary incontinence also had fecal incontinence compared to no children of the healthy controls. In children with combined elimination disorders (wetting during daytime/nighttime and soiling), the rate of comorbid psychologically disorders is increased (von Gontard & Hollmann, 2004).

– Comorbid Somatic Disorders

All somatic disorders presented in the section of “differential diagnoses and comorbid disorders,” can also occur as comorbid disorders. Special attention should be paid to the vesicoureteral reflux and concomitant infections of the urinary tract.

Treatment of Daytime Urinary Incontinence

Basic modules for treatment of daytime urinary incontinence are presented in this section. An exact diagnosis of the subtype of urinary incontinence is necessary for a successful therapy. At the beginning of the treatment, detailed psychoeducation with the provision of information and counsellng of children and parents is indicated.

1. Urge Incontinence

First-line treatment of urge incontinence consists of detailed pschoeducation and takes a cognitive approach. Children are instructed to perceive urgency and to go to the toilet immediately at the first signs of urge. They are asked to note in a voiding chart whether their underwear was dry or wet (e.g., using symbols such as a flag or a laughing smiley for dryness, a cloud or a sad smiley for wetting).

Clinical experience has shown that this method can reduce wetting within a few weeks in one third of the children.

Hagstroem and colleagues (2010) showed that 30% of all children with urge incontinence became dry through urotherapy in combination with programmed watches that reminded them to go to the toilet regularly. Pharmacological treatment with anticholinergics was not necessary.

However according to clinical experience, for two thirds of the children additional pharmacological treatment with an anticholinergic (such as Oxybutynin, Propiverine, Tolterodine, or Trospium) is necessary. The drugs lead to a reduction of bladder contractions. The parasympathetic innervations is inhibited and sensitivity decreases. Thereby, the bladder can store more urine and does not contract so easily, reducing urgency and frequency.

2. Voiding Postponement

In addition to psychoeducation, the treatment of voiding postponement consists of a cognitive behavioral approach. The children are instructed to go to the toilet at least 7 times a day and note each micturition in a voiding chart. Through this timed voiding, micturition frequency is increased and postponement behavior is reduced. It is often necessary to combine the approach with positive reinforcement, especially in children with low compliance or oppositional behavior.

Reminders to go the toilet with programmed watches (or cell phones) can be helpful. Although only children with urge incontinence were included in the study by Hagstroem and colleagues (2010), timed voiding is especially suitable for children with voiding postponement.

3. Dysfunctional Voiding

In dysfunctional voiding, biofeedback is the treatment of choice. In biofeedback, electromyograms (EMG) are used to present either uroflow or pelvic floor contractions acoustically or optically (curves are shown on a screen). Child-appropriate animations are available.

Biofeedback training with uroflow and EMG can only be conducted at the clinic or practice. However, EMG biofeedback programs are available for home use. The children receive a portable biofeedback device with which they can train to relax the muscles of the pelvic floor at home. The biofeedback training is an effective, noninvasive treatment of dysfunctional voiding (Desantis, Leonard, Preston, Barrowman, & Guerra, 2011). Chase and Colleagues (2010) described this treatment approach according to the ICCS standards.