Lower urinary tract dysfunction in patients with parkinsonism and other neurodegenerative disorders

Progressive neurodegenerative disorders are devastating diseases with often fatal outcomes. Lower urinary tract symptoms (LUTS) add to morbidity and increase the risk of becoming dependent on the help of others (e.g., nursing-home referral). In Parkinson's disease (PD), the specific loss of dopaminergic neurons in the substantia nigra and possibly also in the ventral tegmental area induces loss of neurogenic bladder control through dysfunction of a complex network in which selective disinhibition of bladder reflexes is lost. In PD, more than 60% of patients have troublesome bladder symptoms, and 30% experience incontinence, though not daily. In atypical parkinsonism, including multiple system atrophy, LUTS are highly prevalent, and the onset of LUTS in comparison to other autonomic symptoms and motor symptoms may serve as a diagnostic marker. Less is known about the pathophysiology of incontinence in Alzheimer's disease, but higher cognitive function including attention and self-management may play a role. Incontinence is a major risk factor for loss of independence. The complex pathophysiologic mechanisms of neurodegenerative disorders and hence complex symptoms play important roles in LUTS and patient quality of life. Nocturia, incontinence, and urgency as well as poor bladder emptying are the most common symptoms. These symptoms may interact with the core symptoms of the disorders, increasing the risk of incontinence and infection. In rarer neurogenerative disorder LUTS may be present, most commonly in disorders with spinal cord involvement. The systematic and careful tracking of symptoms, evaluation using non-invasive techniques, and conservative management including pharmacologic treatments can often markedly improve the lives of patients and their caregivers.