Overview. Nocturnal enuresis is involuntary urination during sleep – more commonly called bedwetting – beyond an appropriate age (around 5 years old). It is among the most common pediatric health issues and, although it can be unsettling for children and their families, it generally should not be a cause for concern. The condition is known as primary nocturnal enuresis when the child has never been consistently dry at night; children with secondary nocturnal enuresis start wetting their bed after having stayed dry for an extended period.
Incidence. An estimated 5-7 million children in the United States have nocturnal enuresis, three-fourths of them boys. Almost all girls are able to stay dry by the age of 6, and boys by the age of 7. It’s estimated that about one in five children wet the bed at least monthly at age 5, and that 5 percent of boys and 1 percent of girls that age wet the bed nightly. Among 12-year-olds, approximately 8 percent of boys and 4 percent of girls are enuretic; 1-3 percent of adolescents and 1-2 percent of adults have the condition.
Causes and Risk Factors. Once thought to be a psychological problem, nocturnal enuresis is now believed to be attributable to physiological factors in the vast majority of cases. For most children there is no underlying disease that explains the bedwetting – merely an inability to recognize and be awakened by the feeling of a full bladder, most likely caused by a developmental delay in the bladder that the child will eventually outgrow. It is significantly more likely to occur if one or both parents have had the problem, and if the child’s bladder is small. There is no evidence that stress, emotional disturbances or similar factors cause enuresis. Similarly, there is little evidence to support the theory that sleep disorders are a culprit. In a small number of cases, bladder problems can be the cause. Insufficient production of the antidiuretic hormone (ADH), which decreases urine output during sleep, may also contribute.
Diagnosis. For diagnosis of nocturnal enuresis to occur, children must be at least 5 and have two or more bed-wetting incidents per month. (Mentally disabled children should have reached a mental age of 4.) The evaluation involves a thorough history, physical examination, and urinalysis. Factors other than enuresis that could be responsible for the bed-wetting include spinal cord injuries resulting in a neurogenic bladder, urinary tract infections, and other causes of voiding dysfunction such as congenital anomalies involving the urinary tract. If there is a normal history, physical exam and urine test, further testing is usually not needed.
Treatment. A wide variety of therapies, both behavioral and medical, are available, and the approach to treatment – or whether it is needed at all – depends on the extent to which the enuresis is affecting the child and his or her social development. Behavioral options range from use of a bed-wetting alarm (studies have shown this to be the most effective non-pharmacological strategy), which make a sound during voiding; to positive reinforcement techniques such as offering a reward for staying dry a certain number of nights. Medications used for enuresis include desmopressin (which decreases urine output during sleep) and imipramine (which relaxes the bladder muscle and may produce lighter sleep).
Most experts advise parents to simply wait out the problem when at all possible. Any efforts to address enuresis should focus on improving the child’s self-esteem. Punishing the child, as some parents are prone to do, can cause psychological harm and affect school performance. It is important for parents to understand that nighttime wetting is not an act of rebellion or failure, but a condition the child cannot control and will eventually outgrow, even without treatment.