Contents
Although it may not seem obvious to everyone, the urinary system is one of the most important systems in the human body. When it works properly, its job is to maintain homeostasis of body fluids by excreting waste products in the form of urine.
How does a healthy urinary system work?
Thanks to the constant work of the kidneys, regulating the content of salts and acids in the body, approx. 170–180 liters of primary urine flows through them a day. It is a fluid that is partly composed of blood plasma which has been filtered through the Malpighi body filtration process. Primary urine contains not only harmful metabolic products that should be removed from the body, but also desirable substances, such as minerals, vitamins, sugars, amino acids and water. Therefore, as the filtrate flows through the long renal tubules, the necessary substances and part of the water are reabsorbed. This process is called reabsorption or resorption. After resorption, the body excretes approximately 1,5 liters of fluid in the form of final urine during the day. In healthy people, an undisturbed cycle looks like this:
- When urine comes out of the collecting tubules, it collects in the renal pelvis. Due to the movement of the ureter, portions of urine continue to travel to the bladder.
- Once the bladder is full (approximately 200, 300 ml) and stretched, irritation of the receptors causes a signal to be sent to the brain which responds by initiating contraction and relaxation of the sphincter smooth muscles. We then say that there is pressure.
- Excretion begins with the relaxation of the sphincters and contraction of the bladder, which pushes the urine out. Urine flows out through the urethra, after which the sphincters constrict and urine begins to accumulate in the bladder again.
The causes of urinary incontinence
Although it might seem that urinary incontinence (NTM for short) is a disorder that is not complicated in terms of genesis – nothing could be further from the truth. Incontinence, because this is the correct medical term for urinary incontinence, takes many forms, in addition, some of the factors responsible for it may occur simultaneously. For many people, trouble getting wet is also linked to other health issues. This happens mainly in the case of metabolic disorders, postoperative complications (e.g. prostate), general, postpartum urogenital problems and diseases of the nervous system (e.g. multiple sclerosis, stroke, spinal cord injuries, old age disorders). Using a broad classification, urinary incontinence can therefore be divided according to the basis:
- physiological,
- neurological and mental,
- other rare genetic and birth defects.
Physiology – the most common cause of trouble
When it comes to the physiological dysfunctions of the organism causing NTM, we most often deal with the so-called stress incontinence and because of an overflow of the bladder. Starting with the first, exercise incontinence is a classic example of weakness in the sphincters, pelvic floor muscles, or excessive mobility of the bladder neck. It is estimated that less than half of people affected by urinary incontinence suffer from this type of disease. Involuntary urination is closely related to exercise, coughing, sneezing, making sudden movements or laughing. This problem relatively rarely affects men, occurring only as a result of complications arising from prostate operations. In the case of women, stress urinary incontinence is much more common. This is because pregnancy, childbirth and the menopause sometimes result in physical changes in the urinary system that make it unregulated.
Overflow incontinence is caused by an obstruction in the outflow of urine from the bladder, which is full, and urine continuously or intermittently leaks out. It most often occurs in men with an enlarged prostate or in people who, due to the weakening of the smooth muscles of the sphincter, are unable to excrete the full content of urine. Overfill incontinence may also be associated with obstructive nephropathy, resulting in abnormalities in the structure of the kidneys. The most common causes of nephropathy are narrowing of the ureter or its opening to the renal pelvis and cancer (uterus, ovary, colon). A developing tumor can compress the nerves responsible for relaxing the sphincters, making it impossible to feel the need to pass urine. Such an obstacle in the outflow of urine from the kidney leads to the development of hydronephrosis, i.e. dilatation of the renal pelvis and calyces. Untreated overflow incontinence may, in extreme cases, lead to renal colic, so after the first symptoms, we should contact a doctor.
Neurological and psychological causes
Urinary incontinence is not only a medical problem, but also a psychological one that can completely disrupt the life of the person affected. According to statistics, NTM affects about 10-15% of every society (it is estimated that up to 4 million people in Poland). Low self-esteem, social isolation, and sexual dysfunction are just some of the psychological effects of physiological incontinence. Sometimes, however, our psyche and dysfunctions of the nervous system are also the cause of it, often on the basis of feedback.
The most common problem related to the neurological aspect is undoubtedly urge incontinence. It is associated with overactive bladder nerves, even when there is a small amount of fluid in the bladder. Patients with urge incontinence (approximately 22% of all NTM cases) may lose small amounts of urine even while sleeping. The involuntary action of the bladder muscles is often associated with multiple sclerosis, Parkinson’s disease, Alzheimer’s disease, stroke or complications following spine surgery.
Additionally, mixed incontinence occurs especially in older women. As it combines NTM with a physiological (exercise) and neurological (pressure) basis, its treatment requires a comprehensive approach to the patient and a combination of surgical methods with drugs and exercises performed at a later stage by the patient (e.g. Kegel exercises).
The second, especially common, case of NTM with indirect neurological and psychological background is the so-called bedwetting. Although the conducted research shows that the main cause of urinary incontinence during sleep is dysfunction of the urinary system, such as abnormal bladder size or bacterial infections, the aspect of the patient’s emotional disorders should not be ignored. In many cases, although they are a side effect, they can make things significantly worse. First of all, if the medical diagnosis does not show any abnormalities in the development of the child’s urinary system, it means that bedwetting is associated with the body’s maturation and it simply has to be “survived”. In this case, it is necessary not only to limit fluid intake before bedtime, but above all to support the child and not to blame him for the problem. As parents, first of all, let’s avoid the vicious circle, which works on the principle – temporary problems with physiological incontinence, under the influence of strong emotional experiences related to reprimand, turn into a chronic psychological problem in a child. In adults, sleep incontinence has a more complex genesis and in many cases is the result of a trauma or post-traumatic shock.
Rare cases
Although the types of incontinence described here account for approximately 80% of all cases, there are also complicated exceptions in this matter. One of them is extra-urethral incontinence, which is manifested by its leakage through openings other than fistulas, i.e. the opening of the external urethra. This is the constant loss of urine, which may go directly into the abdominal cavity or vagina, for example. The most common causes are congenital improper connections of the urinary tract. This type of incontinence must be treated surgically. The exception are artificial fistulas, e.g. in the case of chronic enteritis.
Regardless of the NTM case that affects us, there is one correlation to remember – without proper treatment our condition will only worsen. Since incontinence is an embarrassing problem, we often hope that it will go away on its own without the need to contact a doctor. Unfortunately, nothing could be more wrong. While in the early stages, exercise and overflow NTM are relatively manageable with proper therapy, over time, if neglected, urinary tract infections and kidney problems can lead to serious complications. Let us not underestimate the problem, even when it comes to small amounts of urine. In many cases, incontinence can be a side effect of much more serious neurological complications and an early warning sign of cancer.
Andrzej Dębski