How might Parkinson’s affect bladder problems?

Bladder difficulties can be common amongst people with Parkinson’s, particularly in the later stages of the disease. The loss of dopamine and the resultant interruption of signals from the brain, can mean that the messages telling the bladder to retain or expel urine are disrupted.

However, it is important to stress that bladder problems are not inevitable with Parkinson’s. If difficulties do arise, especially in older people, they may be caused by factors totally unrelated to the disease and, as such, a thorough medical evaluation would be recommended, including a medical history, clinical examination and, if appropriate, further investigations (tests).

Bladder problems associated with Parkinson’s include:

1. Urinary incontinence
   1. the detrusor muscle, which relaxes to allow the bladder to fill and contracts to expel urine, can become unstable resulting in urge incontinence. Often the muscle will contract erratically and just with small volumes of urine in the bladder. This instability becomes more common in the later stages of Parkinson’s and major urgency in early stages should prompt one to investigate diagnoses unrelated to the disease, such as prostate problems in men, or consider the possibility that the person may have another form of Parkinsonism, such as Multiple System Atrophy (MSA)
   2. physical problems, such as reduced mobility, particularly in the later stages of Parkinson’s, can prevent the person from getting to the toilet in time when they have an urgent need to go, resulting in urge incontinence.  Falls may also result when trying to reach the toilet urgently, particularly in people who experience freezing or bradykinesia
      
   3. difficulties with the practicalities of using the toilet, such as undoing clothing and the process of sitting on the toilet, can also lead to urge incontinence if the bladder begins to contract involuntarily
   4. a frequent need to go to the toilet during the night (nocturia), or night-time incontinence (nocturnal enuresis), when the person is unable to reach the toilet in time, can lead to sleep disruption. It is worth noting that urine production at night increases as we age.
2. Difficulty emptying the bladder
   1. some people with Parkinson’s find it difficult to pass urine when the bladder fails to contract when required, or because the sphincter doesn’t let urine out - or a combination of the two. This is a result of reduced dopamine levels interfering with the efficiency of the bladder muscles and causes a residual amount of urine to be left in the bladder. This reduces the total amount the bladder can hold and creates a feeling of wanting to empty the bladder very often. Moreover, those people who cannot fully empty their bladder have an increased risk of urinary infection
   2. in some older people, constipation - which is often associated with Parkinson’s - can result in faeces collecting in the rectum. This puts pressure on the urethra (the tube leading from the bladder to the outside) and may even obstruct it. The bladder is then unable to empty and may continue distending, causing dribbling incontinence
   3. anticholinergic medications can also make emptying problems worse.