With respect to urinary incontinence of young people, women are mainly affected. However, seniors of both sexes know the taboo subject – at the age of 80 plus three out of ten people suffer from it. They experience incontinence as something extremely stressful and often arrive at the doctor already with serious malfunctions.
In a healthy state, stretch receptors report to the brain on how full our bladder is. In order to prevent involuntary urination, sympathetic nerves relax the detrusor muscle and contract the internal sphincter. During micturition this is reversed: parasympathetic nerves contract the detrusor muscle and relax the sphincter. Depending on the symptoms, the bladder signals too early that a toilet should be sought, or involuntary loss of urine happens.
In order to have an essential medical history patients should fill out a voiding diary. This includes drinking habits: as a U.S. project involving 4,000 patients has shown, incontinence occurs significantly more often with the consumption of more than 204 milligrams of caffeine per day than in a comparison group. Urologists advised for that reason to avoid diuretic beverages such as coffee, tea and alcohol – however for incontinence patients fluid intake should not fall short of a minimum two litres per day. Bacterial or viral infections often also lead to this set of symptoms. It”s also worth taking a look at medication: ACE inhibitors may trigger stress incontinence, while with some antidepressants or calcium channel blockers urinary retention is a thing that is likely to occur. After further investigation including imaging and urodynamics, a diagnosis is usually established. Stress and urge incontinence occur especially often, including various combined forms.
When the bladder pushes
Patients describe urge incontinence (overactive bladder) as a sudden, extreme need to urinate. Here the bladder wall gives a false alarm – when in reality there would be enough room to store more urine. There can be other underlying diseases hiding behind the symptoms, such as a prostate hyperplasia or an urethral stricture, bladder stones or tumors of the bladder wall should also be taken into consideration as possible causes. If the signaling for controlling the detrusor muscle is out of control, neuronal diseases also come into question. If such suspicions are however ruled out, the bladder itself becomes the focus of attention.
Nerves under control
In a healthy body acetylcholine controls the detrusor muscle – a potential therapeutic target: anticholinergics weaken its contraction. The respective receptors however not only exist in the bladder. With older, less selective drugs such as oxybutynin or propiverine, side effects for this reason are not to be struck from the list of possible outcomes. Modern drugs such as darifenacin and solifenacin bind to the M3-muscarinic receptor of the detrusor muscle with higher affinity than, for example, to M1 or M2 receptors of other organ systems. Central or cardiac effects hardly occur here any more. And with regard to the new β3 receptor agonist Mirabegron, researchers are following a similar path: due to its selectivity, the drug relaxes only muscles in the bladder, while the effects of adverse events are measurably less than placebo level. In the U.S., the substance has already been approved. If pharmacotherapy should not be possible due to existing medical conditions, an option that still remains is botulinum toxin A. Injected in the detrusor, the force of its contraction weakens for up to nine months. Patients report a reduced urinary urge, the voiding volume increases. At high doses however an evacuation disorder can be triggered.
Bladder heavily loaded
In contrast to urge incontinence, patients with stress urinary incontinence (SUI) involuntarily lose urine during sports, while lifting heavier loads, but even when laughing, sneezing or coughing. There is usually a pelvic floor weakness as a cause behind this, which affects women after pregnancy and childbirth and menopause. Gynaecologists and urologists attempt via gymnastics to stabilise the floor of the pelvis. For relaxation of the muscles, electrical stimulations as well as biofeedback methods are of help. And vaginal pessaries or vaginal cones bring organs that have slipped via a prolapse back to their original positions. Many women also benefit from a reduction in weight, as one study with 335 patients has shown. After those affected had slimmed down by 5.5 to 8.0 percent, their incontinence episodes decreased significantly.
Reaching into the pharmaceutical treasure chest
If these strategies do not hit the mark, there are also pharmaceutical aids such as duloxetine. This selective serotonin-norepinephrine reuptake inhibitor (SNRI), originally developed as an antidepressant, increases the tone of the urethral sphincter. Duloxetine is only issued to women with moderate to severe SUI, however off label it comes into use with men after a prostatectomy. Nevertheless targeted pelvic floor training also helps men.
Scalpel: quite rare
If these measures do not bear fruit, what remains as a last resort is to implant a hydraulically controlled urinary sphincter. The pump itself, which is located in the testicle with men, releases a cuff upon pressing a button, and the urine can then drain out. With this system, up to 96 percent of all patients become sufficiently continent so as to be active again in working life and to participate in leisure time activities. With women the Tension Free Vaginal Tape (TVT) procedure has in recent years found a place more and more: surgeons put an artificial belt without applying tension beneath the urethra in order to compensate for defects of the connective tissue and bands. Operations such as colposuspension which raises the bladder neck have, in view of the numerous alternatives, become rare today. What’s more injections using biomaterials such as hyaluronic acid or collagen are not the first drug of choice, as the methods have not shown any good long-term results in studies.