There are two main types of bedwetting in adults, also known as adult enuresis, and the causes are typically different for each type. Primary nocturnal enuresis, or PNE, is when patients have wet the bed since childhood and have never gone for any significant time without the problem. These people typically have a physical issue contributing to the problem, such as an overactive detrusor muscle, low functional bladder capacity, or an imbalance in production of antidiuretic hormone. Those with adult onset enuresis, where bedwetting starts in adulthood after a long period when it did not occur, should seek medical attention, as the condition is often the result of another, potentially serious, issue. Some possible causes for the late development of adult enuresis include urinary tract or bladder issues, anxiety disorders, or certain types of cancer.
For some people, adult enuresis is a continuation of a lifelong struggle to control urination during sleep. This is usually the result of an underlying medical condition. There is also some evidence that this condition has a genetic component which can be passed from parent to child.
Some people have difficulty controlling the detrusor muscle, which contracts to push urine from the bladder. Others have a lower functional bladder capacity than normal, meaning that even though their bladders are not physically smaller than average, a smaller amount of urine in the organ will trigger the brain to think they need to urinate. In some cases, patients may produce abnormal amounts of antidiuretic hormone, or ADH, which typically tells the kidneys to produce less urine at night.
When adult enuresis first occurs in adulthood, it is often a symptom of another medical issue, such as a sleep disorder, diabetes, or an undiagnosed internal injury to the kidneys, bladder, or spine. Urinary tract issues like infections or stones, as well as bladder problems, may be to blame, and in rare cases it can mean bladder cancer. Since the cause may be serious, sufferers should typically seek out a medical professional to find the root cause.
In men, problems with the prostate like enlargement or cancer can cause urination during sleep, while in women, pelvic issues can be responsible. In certain rare cases, emotional issues or anxiety disorders can trigger bedwetting. Adult enuresis can also be a side effect of certain medications, like thioridazine, dozapine and risperidone.