Bladder dysfunction in Parkinsonism: Mechanisms, prevalence, symptoms, and management

Treatment Options for Urogenital Dysfunction in Parkinson's Disease

Urogenital dysfunction is commonly reported in Parkinson’s disease (PD), and history taking and a bladder diary form the cornerstone of evaluation. The assessment of lower urinary tract (LUT) symptoms include urinalysis, ultrasonography, and urodynamic studies and help to evaluate concomitant urological pathologies such as benign prostate enlargement. Antimuscarinic medications are the first line treatment for overactive bladder (OAB) symptoms and solifenacin has been specifically studied in PD. Antimuscarininc drugs may exacerbate PD-related constipation and xerostomia, and caution is advised when using these medications in individuals where cognitive impairment is suspected. Desmopressin is effective for the management of nocturnal polyuria which has been reported to be common in PD. Intradetrusor injections of botulinum toxin have been shown to be effective for detrusor overactivity, however, are associated with the risk of urinary retention. Neuromodulation is a promising, minimally invasive treatment for PD-related OAB symptoms. Erectile dysfunction is commonly reported and first line treatments include phosphodiesterase-5 inhibitors. A patient-tailored approach is required for the optimal management of urogenital dysfunction in PD.

Preserved micturition after intradetrusor onabotulinumtoxinA injection for treatment of neurogenic bladder dysfunction in Parkinson's disease

BACKGROUND

To assess the efficacy and safety of intradetrusor onabotulinumtoxinA (OnabotA) injection treatment in patients with neurogenic lower urinary tract dysfunction (NLUTD), especially for patients with Parkinson disease (PD).

METHODS

PD patients refractory to oral antimuscarinic participated in an off-label use study and were evaluated prior and after 200 IU OnabotA injection into detrusor muscle, including trigone. Changes due to treatment were evaluated using bladder diaries, urodynamics, and questionnaires. Statistical analysis comprised Wilcoxon rank-sum test. Values are presented as mean ± standard deviation.

RESULTS

Ten PD patients (4 female and 6 male, mean age: 67.9 ± 5.36 years) with LUTD were enrolled. All patients tolerated the treatment. Bladder diary variables decreased significantly (p ≤ 0.011) after OnabotA injection compared to variables prior injection. Desire to void and maximum bladder capacity increased significantly in urodynamics (p ≤ 0.05). Maximum detrusor pressure during voiding phase normalised from 56.2 to 18.75 cm/H20. Detrusor overactivity was less often detectable. All patients voided spontaneously. Mean post void residual (PVR) volume was 77.0 ± 119.78 mL postoperatively. No urinary retention or side effects have been observed during/after treatment. Mean follow-up time was 4 months (range of 1-12). 4 patients requested repeated injection after a mean period of 10 months between first and second injection.

CONCLUSIONS

Our data confirm the efficacy and safety of 200 IU OnabotA injection in patients with neurogenic LUTD due to PD. The risk of urinary retention or high post-urinary residual volumes seems to be minor after OnabotA-injection. More research is needed with larger sample size to confirm the significance of these findings.

TRIAL REGISTRATION

TRIAL NUMBER

ISRCTN 11857462 , Registration Date 2016/10/08.

Nocturia in Parkinson's Disease: Why Does It Occur and How to Manage?

BACKGROUND

Nocturia is one of the commonest nonmotor symptoms in Parkinson's disease (PD) and has a significant impact on quality of life both for patients and their carers. There exists a relation between nocturia and poor sleep quality, falls, and institutionalization. Nocturia may manifest as a result of reduced functional bladder capacity or nocturnal polyuria; however, most often the cause is multifactorial. Disorders of circadian rhythm regulation are known to occur with sleep disturbances in PD may also contribute to nocturia.

METHODS AND RESULTS

In this review, an overview of the assessment and management of nocturia in patients with PD is presented. History taking, medication review, and a bladder diary form the cornerstone of the evaluation. Urinalysis, ultrasonography, and urodynamic studies help to assess the cause for lower urinary tract symptoms and exclude concomitant pathologies, such as bladder outlet obstruction. Antimuscarinic medications are the first-line treatment for the overactive bladder; however, caution is needed when using these medications in individuals predisposed to cognitive impairment. Desmopressin is effective for managing nocturnal polyuria.

CONCLUSIONS

An individualized approach is recommended to optimize the management of nocturia in PD.

The use of imaging techniques in understanding lower urinary tract (dys)function

The ability to store urine in the bladder and to void at an appropriate time depends on several complex mechanisms in the lower urinary tract (LUT) and its neural control. Normal LUT function requires coordination of the urinary bladder, urethra, pelvic floor, efferent and afferent neurons and specific spinal cord and brain areas. These structures can be visualised using different imaging modalities, such as ultrasound, X-ray and magnetic resonance imaging. The supraspinal neural control of the LUT can be studied using functional brain imaging. During the last two decades, the many technological improvements of these imaging techniques have increased our knowledge of voiding dysfunction. Here, we review the different imaging modalities of the LUT and its neural control and discuss their importance for diagnosing and understanding voiding dysfunction.

New concepts in the pathogenesis and presentation of Parkinson's disease

Parkinson's disease (PD) was first described by James Parkinson in 1817. He noted the complex nature of this condition and that non-motor symptoms (NMS) underpinned the classic motor symptoms of PD. The concept of what PD is has therefore undergone substantial changes and it is now recognised that PD is a combined motor and non-motor syndrome and NMS are present during the prodromal phase of PD, starting up to 20 years before the first clinical motor signs emerge. PD may originate from pathology in the gut, olfactory bulb and lower brainstem rather than in the substantia nigra. Complex phenotypes of PD may exist where clinical NMS overshadow motor features. Therapy needs to be adjusted based on motor and non-motor loads, ideally using validated tools. Recently, a multimodal biomarker battery in PD has emerged and might play an important role in the future.

Somatic Comorbidity in Women with Overactive Bladder Syndrome

PURPOSE

We explore the influence of co-occurring somatic illnesses on prevalent overactive bladder in women of premenopausal age.

MATERIALS AND METHODS

Data for the present study were derived from a nationwide survey on complex diseases among all twins in the Swedish Twin Registry born 1959 to 1985. The present study was limited to female twins participating in the survey (12,850). Generalized estimating equations were used to estimate odds ratios with 95% CIs. Environmental and genetic influences were assessed in co-twin control analysis.

RESULTS

Generalized estimating equations analysis showed a significant association between overactive bladder and migraine (OR 1.34, 95% CI 1.15-1.57), fibromyalgia (1.83, 1.54-2.18), chronic fatigue (1.81, 1.49-2.19) and eating disorders (1.56, 1.24-1.96). There was also a significant association with allergic disorders including asthma (1.24, 1.01-1.52) and eczema (1.22, 1.04-1.43). Among reproductive disorders, urinary tract infections (1.60, 1.40-1.84), dysmenorrhea (1.53, 1.33-1.76) and pelvic pain (1.60, 1.31-1.94) showed the strongest association with overactive bladder. Results from co-twin control analysis indicated that the significant associations observed in generalized estimating equations analysis were influenced by environmental and genetic factors without a common pathway model.

CONCLUSIONS

Our results suggest a multifactorial and complex pathogenesis of overactive bladder in which associations between various somatic illnesses and overactive bladder may be affected by environmental and genetic factors.

Nocturia in Patients With Parkinson's Disease

Background

Waking up from sleep more than once to pass urine, known as nocturia, is an important nonmotor symptom in Parkinson's disease (PD). Very little is known about the cause for nocturia. The aim of this work was to evaluate lower urinary tract (LUT) symptoms in patients with PD reporting nocturia using standardized validated questionnaires and bladder diaries and to assess the impact of nocturia on quality of life and sleep.

Methods

Twenty-three consecutive patients with PD (17 males, 6 females; mean age: 68.5 years; range, 50-85) referred to a specialist uro-neurology clinic reporting nocturia according to the International Continence Society definition were included. Patients measured their daily fluid intake, urinary output per void, and recorded these with the timing of voids on a 3-day bladder diary. Standardized questionnaires were used to assess LUT symptoms (Urinary Symptom Profile, International Prostate Symptom Score, and Qualiveen Short Form) and sleep quality (Parkinson's Disease Sleep Scale).

Results

Mean duration of PD was 10.1 years, and mean severity on H & Y scale was 3.0 (range, 1.0-5.0). Median duration of LUT symptoms was 6.0 years. Mean night-time urinary frequency was 3.5 (range, 1.0-7.3), and mean nocturnal maximum voided volume was 242 mL. Mean Nocturnal Polyuria Index (NPi) was 0.4 (range, 0.13-0.75), and 13 patients (56.5%) had nocturnal polyuria (NPi > 0.33). Patients with nocturnal polyuria reported more-severe LUT symptoms that impacted quality of life and sleep.

Conclusions

In this preliminary study, nocturnal polyuria seems to be common in patients with PD reporting nocturia and appears to affect quality of life and sleep, though this was not statistically significant. The bladder diary is an essential tool in the assessment of nocturia in patients with PD.

Dopamine is produced in the rat spinal cord and regulates micturition reflex after spinal cord injury

Dopamine (DA) neurons in the mammalian central nervous system are thought to be restricted to the brain. DA-mediated regulation of urinary activity is considered to occur through an interaction between midbrain DA neurons and the pontine micturition center. Here we show that DA is produced in the rat spinal cord and modulates the bladder reflex. We observed numerous tyrosine hydroxylase (TH)⁺ neurons in the autonomic nuclei and superficial dorsal horn in L6-S3 spinal segments. These neurons are dopamine-β-hydroxylase (DBH)^- and some contain detectable dopamine decarboxylase (DDC), suggesting their capacity to produce DA. Interestingly, following a complete thoracic spinal cord injury (SCI) to interrupt supraspinal projections, more TH⁺ neurons emerged in the lumbosacral spinal cord, coincident with a sustained, low level of DA expression there and a partially recovered micturition reflex. Non-selective blockade of spinal DA receptors reduced bladder activity whereas activation of spinal D₂-like receptors increased bladder activity and facilitated voiding. Additionally, depletion of lumbosacral TH⁺ neurons with 6-hydroxydopamine (6-OHDA) decreased bladder non-voiding contractions and voiding efficiency. Furthermore, injecting the transsynaptic neuronal tracer pseudorabies virus (PRV) into the bladder detrusor labeled TH⁺ cells in the lumbosacral cord, confirming their involvement in spinal micturition reflex circuits. These results illustrate that DA is synthesized in the rat spinal cord; plasticity of lumbosacral TH⁺ neurons following SCI may contribute to DA expression and modulate the spinal bladder reflex. Thus, spinally-derived DA and receptors could be a novel therapeutic target to improve micturition recovery after SCI.

Role of the Anterior Cingulate Cortex in the Control of Micturition Reflex in a Rat Model of Parkinson's Disease

PURPOSE

In the current study we examined dynamic changes in neural activity of the anterior cingulate cortex and the midbrain periaqueductal gray during the micturition reflex in a Parkinson's disease model as well as the effects of direct stimulation of the anterior cingulate cortex on the micturition reflex.

MATERIALS AND METHODS

Electrodes were inserted in the anterior cingulate cortex or the periaqueductal gray. The effects of intravenous administration of the adenosine A2A receptor antagonist ZM24138 on pelvic nerve evoked field potentials were examined. The effect of electrical stimulation of the anterior cingulate cortex was also examined.

RESULTS

Rats with Parkinson's disease showed bladder overactivity as evidenced by a significant decrease in the intercontraction interval compared with sham operated rats. Intravenous administration of ZM24138 increased the intercontraction interval in both groups with the inhibitory effects greater in rats with Parkinson's disease. It dose dependently increased the amplitude of evoked potentials in the anterior cingulate cortex of rats with Parkinson's disease but not in sham operated rats. Intravenous administration of ZM24138 decreased evoked potential amplitude in the periaqueductal gray of both groups with the inhibitory effects greater in Parkinson's disease vs sham operated rats. Electrical stimulation of the anterior cingulate cortex significantly increased the intercontraction interval.

CONCLUSIONS

These results suggest that anterior cingulate cortex neurons have an inhibitory role in bladder control. Neural activity in the anterior cingulate cortex was significantly increased along with suppression of bladder overactivity after ZM241385 administration in the Parkinson's disease model and the stimulation of the anterior cingulate cortex inhibited the micturition reflex. Understanding the roles of the anterior cingulate cortex in the modulation of micturition could provide further insights into the pathophysiology of overactive bladder.

α-Synuclein pathology accumulates in sacral spinal visceral sensory pathways

Urinary urgency and frequency are common in α-synucleinopathies such as Parkinson disease, Lewy body dementia, and multiple system atrophy. These symptoms cannot be managed with dopamine therapy, and their underlying pathophysiology is unclear. We show that in individuals with Parkinson disease, Lewy body dementia, or multiple system atrophy, α-synuclein pathology accumulates in the lateral collateral pathway, a region of the sacral spinal dorsal horn important for the relay of pelvic visceral afferents. Deposition of α-synuclein in this region may contribute to impaired micturition and/or constipation in Parkinson disease and other α-synucleinopathies.

A review of lower urinary tract symptoms in patients with Parkinson's disease

To critically review recent literature on lower urinary tract symptoms (LUTS) in patients with Parkinson's Disease.A literature search was conducted using the keywords LUTS, urinary symptoms, non-motor, and Parkinson's disease (PD) via the PubMed/Medline search engine. In the literature, we critically examined lower urinary symptoms in Parkinson's patients by analyzing prevalence, pathogenesis, urinary manifestations, pharmacologic trials and interventions, and prior review articles. The data collected ranged from 1986 to the present with an emphasis placed on recent publications.The literature regards LUTS in PD as a major comorbidity, especially with respect to a patient's quality of life. Parkinson's patients experience both storage and voiding difficulties. Storage symptoms, specifically overactive bladder, are markedly worse in patients with PD than in the general population. Surgical management of prostatic obstruction in PD can improve urinary symptoms. Multiple management options exist to alleviate storage LUTS in patients with PD, ranging from behavioral modification to surgery, and vary in efficacy.Lower urinary tract dysfunction in PD may be debilitating. Quality of life can be improved with a multi-pronged diagnosis-specific approach to treatment that takes into consideration a patient's ability to comply with treatment. A stepwise algorithm is presented and may be utilized by clinicians in managing LUTS in Parkinson's patients.

A guideline for the management of bladder dysfunction in Parkinson's disease and other gait disorders

Parkinson's disease (PD) is a common neurodegenerative disorder, and lower urinary tract (LUT) dysfunction is one of the most common autonomic disorders with an estimated incidence rate of 27-80%. Studies have shown that bladder dysfunction significantly influences quality-of-life (QOL) measures, early institutionalisation, and health economics. We review the pathophysiology of bladder dysfunction in PD, lower urinary tract symptoms (LUTS), objective assessment, and treatment options. In patients with PD, disruption of the dopamine D1-GABAergic direct pathway may lead to LUTS. Overactive bladder (OAB) is the most common LUT symptom in PD patients, and an objective assessment using urodynamics commonly shows detrusor overactivity (DO) in these patients. The post-void residual (PVR) volume is minimal in PD, which differs significantly from multiple system atrophy (MSA) patients who have a more progressive disease that leads to urinary retention. However, subclinical detrusor weakness during voiding may also occur in PD. Regarding bladder management, there are no large, double-blind, prospective studies in this area. It is well recognised that dopaminergic drugs can improve or worsen LUTS in PD patients. Therefore, an add-on therapy with anticholinergics is required. Beta-3 adrenergic agonists are a potential treatment option because there are little to no central cognitive events. Newer interventions, such as deep brain stimulation (DBS), are expected to improve bladder dysfunction in PD. Botulinum toxin injections can be used to treat intractable urinary incontinence in PD. Transurethral resection of the prostate gland (TURP) for comorbid BPH in PD is now recognised to be not contraindicated if MSA is excluded. Collaboration of urologists with neurologists is highly recommended to maximise a patients' bladder-associated QOL. Neurourol. Urodynam. 35:551-563, 2016. © 2015 Wiley Periodicals, Inc.

Randomized, controlled pilot trial of solifenacin succinate for overactive bladder in Parkinson's disease

OBJECTIVE

To evaluate the efficacy of solifenacin succinate in Parkinson's disease (PD) patients suffering from overactive bladder (OAB).

BACKGROUND

Urinary dysfunction is a commonly encountered non-motor feature in PD that significantly impacts patient quality of life.

DESIGN/METHODS

This was a double-blind, randomized, placebo-controlled, 3-site study with an open label extension phase to determine the efficacy of solifenacin succinate in idiopathic PD patients with OAB. Patients were randomized to receive solifenacin succinate 5-10 mg daily or placebo for 12 weeks followed by an 8-week open label extension. The primary outcome measure was the change in the mean number of micturitions per 24 h period. Secondary outcome measures included the change in the mean number of urinary incontinence episodes and the mean number of nocturia episodes.

RESULTS

Twenty-three patients were randomized in the study. There was no significant improvement in the primary outcome measure in the double-blind phase, but there was an improvement in the number of micturitions per 24 h period in the solifenacin succinate group compared to placebo at a mean dose of 6 mg/day (p = 0.01). In the open label phase, the mean number of urinary incontinence episodes per 24 h period decreased (p = 0.03), as did the number of nocturia episodes per 24 h period (p = 0.01). Adverse events included constipation and xerostomia, which resolved after treatment was discontinued.

CONCLUSIONS

In this pilot trial, solifenacin succinate treatment led to an improvement in urinary incontinence, despite persistence in other OAB symptoms.

Current Concepts in the Treatment of Multiple System Atrophy

MSA is a progressive neurodegenerative disorder characterized by autonomic failure and a variable combination of poor levodopa-responsive parkinsonism and cerebellar ataxia (CA). Current therapeutic management is based on symptomatic treatment. Almost one third of MSA patients may benefit from l-dopa for the symptomatic treatment of parkinsonism, whereas physiotherapy remains the best therapeutic option for CA. Only midodrine and droxidopa were found to be efficient for neurogenic hypotension in double-blind, controlled studies, whereas other symptoms of autonomic failure may be managed with off-label treatments. To date, no curative treatment is available for MSA. Recent results of neuroprotective and -restorative trials have provided some hope for future advances. Considerations for future clinical trials are also discussed in this review.

Neural control of the lower urinary tract

This article summarizes anatomical, neurophysiological, pharmacological, and brain imaging studies in humans and animals that have provided insights into the neural circuitry and neurotransmitter mechanisms controlling the lower urinary tract. The functions of the lower urinary tract to store and periodically eliminate urine are regulated by a complex neural control system in the brain, spinal cord, and peripheral autonomic ganglia that coordinates the activity of smooth and striated muscles of the bladder and urethral outlet. The neural control of micturition is organized as a hierarchical system in which spinal storage mechanisms are in turn regulated by circuitry in the rostral brain stem that initiates reflex voiding. Input from the forebrain triggers voluntary voiding by modulating the brain stem circuitry. Many neural circuits controlling the lower urinary tract exhibit switch-like patterns of activity that turn on and off in an all-or-none manner. The major component of the micturition switching circuit is a spinobulbospinal parasympathetic reflex pathway that has essential connections in the periaqueductal gray and pontine micturition center. A computer model of this circuit that mimics the switching functions of the bladder and urethra at the onset of micturition is described. Micturition occurs involuntarily in infants and young children until the age of 3 to 5 years, after which it is regulated voluntarily. Diseases or injuries of the nervous system in adults can cause the re-emergence of involuntary micturition, leading to urinary incontinence. Neuroplasticity underlying these developmental and pathological changes in voiding function is discussed.

Local Change in Urinary Bladder Contractility Following CNS Dopamine Denervation in the 6-OHDA Rat Model of Parkinson's Disease

BACKGROUND

Urinary problems, including urinary frequency, urgency, and nocturia are some of the non-motor symptoms that correlate most with poor quality of life in Parkinson's disease. However, the mechanism behind these symptoms is poorly understood, in particular regarding peripheral bladder pathophysiology following dopamine degeneration.

OBJECTIVE

In this study, we compared the contractile responsiveness of urinary bladder from the 6-OHDA unilateral rat model of Parkinson's disease with that of normal untreated animals.

METHODS

The contractility of the urinary detrusor muscle was evaluated in bladder strip preparations using electrical field stimulation, and muscarinic and purinoceptor stimulations in an vitro organ bath setup.

RESULTS

Our data show that the overall contractile response following electrical field stimulation was significantly higher (43% at maximum contraction by 20-40 Hz stimulation) in the 6-OHDA-lesioned rats as compared to control animals. This increase was associated with a significant increase in the cholinergic contractile response, where the muscarinic agonist methacholine produced a 44% (at 10 -4 M concentration) higher response in the 6-OHDA-treated rats as compared to controls with a significant left-shift of the dose response. This indicates an altered sensitivity of the muscarinic receptor system following the specific central 6-OHDA-induced dopamine depletion. In addition a 36% larger contraction of strips from the 6-OHDA animals was also observed with purinoceptor activation using the agonist ATP (5×10 -3 M) during atropine treatment.

CONCLUSIONS

Our data shows that it is not only the central dopamine control of the micturition reflex that is altered in Parkinson's disease, but also the local contractile function of the urinary bladder. The current study draws attention to a mechanism of urinary dysfunction in Parkinson's disease that has previously not been described.

An update on the cerebellar subtype of multiple system atrophy

Multiple system atrophy is a rare and fatal neurodegenerative disorder characterized by progressive autonomic failure, ataxia and parkinsonism in any combination. The clinical manifestations reflect central autonomic and striatonigral degeneration as well as olivopontocerebellar atrophy. Glial cytoplasmic inclusions, composed of α-synuclein and other proteins are considered the cellular hallmark lesion. The cerebellar variant of MSA (MSA-C) denotes a distinctive motor subtype characterized by progressive adult onset sporadic gait ataxia, scanning dysarthria, limb ataxia and cerebellar oculomotor dysfunction. In addition, there is autonomic failure and variable degrees of parkinsonism. A range of other disorders may present with MSA-C like features and therefore the differential diagnosis of MSA-C is not always straightforward. Here we review key aspects of MSA-C including pathology, pathogenesis, diagnosis, clinical features and treatment, paying special attention to differential diagnosis in late onset sporadic cerebellar ataxias.

Efficacy and safety of intravesical onabotulinumtoxinA injection on elderly patients with chronic central nervous system lesions and overactive bladder

PURPOSE

Intravesical injection of onabotulinumtoxinA is an effective treatment for overactive bladder (OAB). Nonetheless, the treatment outcome is unclear in OAB patients with central nervous system (CNS) lesions. This study evaluated the efficacy and safety of intravesical onabotulinumtoxinA treatment in elderly patients with chronic cerebrovascular accidents (CVAs), Parkinson's disease (PD) and dementia.

MATERIALS AND METHODS

Patients with CVA, PD, dementia, and OAB refractory to antimuscarinic therapy were consecutively enrolled in the study group. Age-matched OAB patients without CNS lesions were selected to serve as a control group. OnabotulinumtoxinA (100 U) was injected into the bladder suburothelium at 20 sites. The clinical effects, adverse events, and urodynamic parameters were assessed at baseline and 3 months post-treatment. The Kaplan-Meier method was used to compare long-term success rates between groups.

RESULTS

A total of 40 patients with OAB due to CVA (23), PD (9), dementia (8) and 160 control patients were included in this retrospetive analysis. Improvement of urgency severity scale, increased bladder capacity and increased post-void residual volume were comparable between the groups at 3 months. Patients with CNS lesions did not experience increased risks of acute urinary retention and urinary tract infection; nonetheless, patients with CVA experienced a higher rate of straining to void. Long-term success rates did not differ between the patients with and without CNS lesions.

CONCLUSION

Intravesical injection of 100 U of onabotulinumtoxinA effectively decreased urgency symptoms in elderly OAB patients with CNS lesions. The adverse events were acceptable, and long-term effects were comparable to OAB patients in general. Nonetheless, the possibility of longstanding urinary retention and chronic catheterization need careful evaluation for this very vulnerable population before choosing intravesical onabotulinumtoxinA treatment.

Autonomic disorders predicting Parkinson's disease

It is now well recognized that there is a premotor phase of Parkinson's disease (PD) with hyposmia and REM sleep behavior disorder caused by degeneration of specific CNS neurons. Most patients with PD describe autonomic symptoms at the time of diagnosis suggesting that these features may have potential sensitivity as clinical biomarkers of the premotor phase. The recognition that damage to peripheral autonomic neurons is present in the early stages of PD has led to a search for specific abnormalities in autonomic function that could serve as predictive biomarkers. There is evidence that constipation, urinary and sexual dysfunction and more recently decreased cardiac chronotropic response during exercise, are part of the premotor parkinsonian phenotype. The sensitivity and specificity of these features has yet to be accurately assessed. We briefly review the evidence for autonomic dysfunction as biomarker of premotor PD.

Multiple system atrophy as emerging template for accelerated drug discovery in α-synucleinopathies

There is evidence that the α-synucleinopathies Parkinson's disease (PD) and the Parkinson variant of multiple system atrophy (MSA-P) overlap at multiple levels. Both disorders are characterized by deposition of abnormally phosphorylated fibrillar α-synuclein within the central nervous system suggesting shared pathophysiological mechanisms. Despite the considerable clinical overlap in the early disease stages, MSA-P, in contrast to PD, is fatal and rapidly progressive. Moreover recent clinical studies have shown that surrogate markers of disease progression can be quantified easily and may reliably depict the rapid course of MSA. We therefore posit that, MSA-P may be exploited as a filter barrier in the development of disease-modifying therapeutic strategies targeting common pathophysiological mechanisms of α-synucleinopathies. This approach might reduce the number of negative phase III clinical trials, and, in turn, shift the available resources to earlier development stages, thereby increasing the number of candidate compounds validated.

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α-synucleinopathies overlap at multiple levels.

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α-synucleinopathies are characterized by an abnormal deposition of α-synuclein.

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Validated surrogate markers in MSA reliably monitor disease progression.

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MSA may serve as a template disease for other α-synucleinopathies.

Morbidity in early Parkinson's disease and prior to diagnosis

BACKGROUND

Nonmotor symptoms are probably present prior to, early on, and following, a diagnosis of Parkinson's disease. Nonmotor symptoms may hold important information about the progression of Parkinson's disease.

OBJECTIVE

To evaluated the total early and prediagnostic morbidities in the 3 years before a hospital contact leading to a diagnosis of Parkinson's disease.

METHODS

Retrospective morbidity data from Danish National Patient Registry records (1997-2007) of 10,490 adult patients with a secondary care diagnosis of Parkinson's disease were compared with 42,505 control cases.

RESULTS

Parkinson's disease was associated with significantly higher morbidity rates associated with conditions in the following categories: mental and psychiatric, nervous system, gastrointestinal, musculoskeletal system and connective tissue, genitourinary, abnormal clinical and laboratory findings, injury, poisoning and certain other external causes, and other factors influencing health status and contact with health services. It was negatively associated with neoplasm, cardiovascular, and respiratory diseases.

CONCLUSIONS

Patients with a diagnosis of Parkinson's disease present significant differences in morbidities early on, following, and prior to, their diagnosis, compared with healthy controls.

Nonmotor symptoms of Parkinson’s disease

Nonmotor symptoms occur commonly in Parkinson's disease (PD) patients and are frequently under-recognized and undertreated. Symptoms include sleep abnormalities, fatigue, autonomic disturbances, mood disorders and cognitive dysfunction. Early recognition and treatment of nonmotor symptoms in PD is critical to providing optimal management. A new screening questionnaire and the revised Unified PD Rating Scale should assist healthcare providers to better identify and evaluate these symptoms. This article reviews the identification and treatment of nonmotor symptoms in PD.

Clinical and pathological features of Parkinson's disease

Parkinson's disease (PD) is, after Alzheimer's disease, the second most common neurodegenerative disorder with an approximate prevalence of 0.5-1% among persons 65-69 years of age, rising to 1-3% among persons 80 years of age and older. Pathologically, PD is characterized by the loss of neurons in the substantia nigra pars compacta (SNpc), and by the presence of eosinophilic protein deposits (Lewy bodies) in this region, in other aminergic nuclei and in cortical and limbic structures. Moreover, it has now been shown that pathology also involves the peripheral nervous system. Braak and colleagues suggested a thread of pathology starting from the vagal nerve to progress to the brainstem, and eventually to limbic and neocortical brain regions. This progression of pathology may account for the clinical evolution of PD toward a composite symptomatology. However, this hypothesis has been criticized by others. In this chapter, we review the clinical features of PD (motor and nonmotor) and their pathological correlates.

Central nervous targets for the treatment of bladder dysfunction

BACKGROUND

The functions of the lower urinary tract, to store and periodically release urine, are dependent on the activity of smooth and striated muscles in the urinary bladder, urethra, and external urethral sphincter. This activity is in turn controlled by neural circuits in the brain, spinal cord, and peripheral ganglia.

AIMS

This paper will review recent advances in our understanding of the pathophysiology of voiding disorders, especially focusing on the central nervous system.

METHODS

Various neurotransmitters, including acetylcholine, norepinephrine, dopamine, serotonin, excitatory and inhibitory amino acids, adenosine triphosphate, nitric oxide, and neuropeptides, have been implicated in the neural regulation of the lower urinary tract.

RESULTS

Injuries or diseases of the nervous system, as well as drugs and disorders of the peripheral organs, can produce voiding dysfunctions such as urinary frequency, urgency, or incontinence.

CONCLUSION

We discuss the potential targets in the central nervous system and new modalities for the treatment of voiding dysfunction.

Effective management of lower urinary tract dysfunction in idiopathic Parkinson's disease

Parkinson's disease, also known as paralysis agitans, is a progressive degenerative disorder of the central nervous system, with onset usually between the ages of 50 and 65 years, and is associated with loss of dopaminergic neurons in the subsantia nigra and the presence of Lewy bodies. It is characterized by the triad of resting tremor, muscular rigidity and bradykinesia. Often-accompanying abnormalities include disorders of equilibrium, posture and autonomic function, including micturition. Symptoms from the lower urinary tract add a significant comorbidity factor in these patients. The incidence and prevalence of lower urinary tract dysfunction rise with increasing progression of the underlying neurological disease. They present a troublesome and difficult to treat health issue with a profound impact on the patient's quality of life. Storage symptoms seem to predominate. In the long term, renal function might be compromised, mainly as a result of elevated intravesical pressure. Various conservative, minimally-invasive and surgical treatment options are available to prevent harmful sequelae, and to improve the quality of life of these patients. We present an overview of current and prospective treatment strategies.

Time-dependent changes and gender differences in urinary dysfunction in patients with multiple system atrophy

AIMS

Because time-dependent changes and gender differences in urinary dysfunction in patients with multiple system atrophy (MSA) are yet unknown, we aimed to determine these parameters through a combination of urodynamic examination and the results of a questionnaire on urinary symptoms.

METHODS

We retrospectively reviewed 66 patients with MSA who responded to a urinary symptoms questionnaire and underwent urodynamic examination more than twice. The participants' mean age was 62 years and mean disease duration at the first urodynamic examination was 3.2 years. Mean duration between the first and second urodynamic examination was 441 days.

RESULTS

With regard to overall (both genders) time-dependent change, none of the urinary symptoms showed significant differences. In the urodynamic examination there were significant differences in reduced urine flow, increased post-void residuals, and decreased detrusor contractility at the second examination. With regard to gender differences, at the first examination, night-time urinary frequency, and voiding symptoms were significantly more severe in male than in female patients; however, at the second examination, except for urinary urgency, gender differences were not observed for any other symptoms. In urodynamic examination, the degree of detrusor contraction was significantly less in male patients at the first examination. However, no significant differences were found in urodynamic examination at the second examination.

CONCLUSIONS

The present study indicates that voiding dysfunction progressed without significant worsening of voiding symptoms. In addition, gender differences are important in evaluating urinary dysfunction being basically less severe in female than in male patients, at least during the early stage. Neurourol. Urodynam. 33:516-523, 2014. © 2013 Wiley Periodicals, Inc.

Managing palliative care in Parkinson’s disease from diagnosis to end-stage disease: what the clinician should know

SUMMARY Progression of Parkinson’s disease (PD) is followed by aggravation of both motor and non-motor symptoms, which calls for more prominent palliative care towards the end stage of the disease. These palliative services should include multidisciplinary teamwork, in addition to taking into account treatment side effects, dose readjustment, and add-on nonpharmaceutical and pharmaceutical approaches. The treatment protocols in the advanced stage of PD are quite different from the ones in the early stages. The focus is shifted from symptom relief strategies to providing the patient with comfort and support during the palliative stage. In this review, some specific palliative approaches for dealing with motor and non-motor complications of end-stage PD are provided, as well as some general knowledge on palliation.

Autonomic dysfunction in Parkinson's disease

Growing recognition of the non-motor features of Parkinson's disease (PD) has led to increased awareness of autonomic dysfunction as part of the disease process, not only in advanced disease but also early in its course, sometimes even preceding the development of the classic motor features of PD. Virtually all aspects of autonomic function can become impaired in PD, including cardiovascular, gastrointestinal, urological, sexual and thermoregulatory function. Recognition of the various autonomic abnormalities of PD is important because effective treatment may be available and may measurably improve quality of life for individuals with PD.

Management of motor and non-motor symptoms in Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder that affects approximately 1 % of people over the age of 60 years. Accurate diagnosis and individualized assessment of the risks and benefits of available antiparkinsonian medications as well as specific clinical features and the phase of disease should guide treatment for patients with PD. Levodopa still remains the gold standard for the treatment of motor symptoms of PD but dopamine agonists (DAs), catechol-O-methyltransferase (COMT) inhibitors and monoamine oxidase B (MAO-B) inhibitors have also been developed to provide more continuous oral delivery of dopaminergic stimulation in order to improve motor outcomes and decrease the risk of levodopa-induced motor complications. Deep-brain stimulation as well as other invasive therapies can be used for the treatment of drug-refractory levodopa-induced motor complications. Despite all of the therapeutic advances achieved within the last 20 years, PD continues to be a progressive disorder leading to severe disability caused by motor and non-motor symptoms. To date, neuroprotective interventions able to modify PD progression are not available. This review focuses on medical and invasive treatment strategies for early and advanced stages of PD as well as on the treatment of PD non-motor symptoms such as mood and behavioural disorders, cognitive and autonomic dysfunction, and sleep disorders, which can antedate PD motor symptoms for years.

Bladder dysfunction in a transgenic mouse model of multiple system atrophy

Multiple system atrophy (MSA) is an adult-onset neurodegenerative disorder presenting with motor impairment and autonomic dysfunction. Urological function is altered in the majority of MSA patients, and urological symptoms often precede the motor syndrome. To date, bladder function and structure have never been investigated in MSA models. We aimed to test bladder function in a transgenic MSA mouse featuring oligodendroglial α-synucleinopathy and define its applicability as a preclinical model to study urological failure in MSA. Experiments were performed in proteolipid protein (PLP)-human α-synuclein (hαSyn) transgenic and control wild-type mice. Diuresis, urodynamics, and detrusor strip contractility were assessed to characterize the urological phenotype. Bladder morphology and neuropathology of the lumbosacral intermediolateral column and the pontine micturition center (PMC) were analyzed in young and aged mice. Urodynamic analysis revealed a less efficient and unstable bladder in MSA mice with increased voiding contraction amplitude, higher frequency of nonvoiding contractions, and increased postvoid residual volume. MSA mice bladder walls showed early detrusor hypertrophy and age-related urothelium hypertrophy. Transgenic hαSyn expression was detected in Schwann cells ensheathing the local nerve fibers in the lamina propria and muscularis of MSA bladders. Early loss of parasympathetic outflow neurons and delayed degeneration of the PMC accompanied the urological deficits in MSA mice. PLP-hαSyn mice recapitulate major urological symptoms of human MSA that may be linked to αSyn-related central and peripheral neuropathology and can be further used as a preclinical model to decipher pathomechanisms of MSA.

[Lower urinary tract dysfunctions in parkinsonian syndromes: a review by the Neuro-Urology Comittee of the French Association of Urology]

INTRODUCTION

Lower urinary tract disorders (LUTD) are common in Parkinson's disease (PD) and other parkinsonian syndromes (PS). They are responsible for a significant morbidity and mortality and impair patients' quality of life. The therapeutic management of these LUTD requires to know how to distinguish the PD from other PS and their epidemiology and pathophysiology.

OBJECTIVE

To provide a diagnostic and therapeutic management of LUTD in patients with PS.

METHOD

A review of litterature using PubMed library was performed using the following keywords: Parkinson's disease, multiple system atrophy, lower urinary tract disorders, neurogenic bladder, overactive bladder, obstruction, anticholinergics, dopamine, prostate surgery.

RESULTS

Sometimes revealing the neurological disease, LUTD in PS raise a diagnostic problem because they occur at an age when various urogynecological disorders can be intricated with neurogenic bladder dysfunction. The differential diagnosis between PD and multiple system atrophy is important to know by the urologist. The distinction is based on the semiological analysis, the clinical response to dopaminergic therapy and the clinical outcome but also on data from urodynamic explorations. The therapeutic management of these LUTD cannot be easy due to the difficulty of use of some pharmacological treatments and the risk of deterioration after inappropriate surgery. The different treatments include the careful use of anticholinergics, posterior tibial nerve stimulation, deep thalamic stimulation and low-dose intradetrusor injections of botulinum toxin without approval. The decision to perform prostate surgery will be taken with caution after proving the bladder obstruction.

CONCLUSION

When analysing LUTD in PS, the urologist must know to question the initial diagnosis of PD. Treatments in order to reduce morbidity and mortality of these LUTD and to improve the quality of life of patients suffering from these degenerative diseases, will be proposed after multidisciplinary neuro-urologic concertation. The decision to perform prostate surgery must be taken with caution after proving sub-vesical obstruction.

The micturition switch and its forebrain influences

Dr DeGroat and Wickens has reviewed the central neural mechanisms controlling the lower urinary tract with a major focus on the brain stem circuitry that mediates the switch-like characteristics of micturition, in particular the periaqueductal grey and the pontine micturition centre (de 2012). The review culminates in a computer model of how the brainstem switch operates in animals in which forebrain influences on micturition have been removed by decerebration. In this complementary paper, we review the mechanisms of forebrain involvement in the voluntary control of human micturition and the maintenance of continence with evidence based heavily on the results of functional brain imaging experiments.

Spinal cord lesions in sporadic Parkinson's disease

In this autopsy-based study, α-synuclein immunohistochemistry and lipofuscin pigment-Nissl architectonics in serial sections of 100 μm thickness were used to investigate the spinal cords and brains of 46 individuals: 28 patients with clinically and neuropathologically confirmed Parkinson's disease, 6 cases with incidental Lewy body disease, and 12 age-matched controls. α-Synuclein inclusions (particulate aggregations, Lewy neurites/bodies) in the spinal cord were present between neuropathological stages 2-6 in all cases whose brains were staged for Parkinson's disease-related synucleinopathy. The only individuals who did not have Lewy pathology in the spinal cord were a single stage 1 case (incidental Lewy body disease) and all controls. Because the Parkinson's disease-related lesions were observable in the spinal cord only after Lewy pathology was seen in the brain, it could be concluded that, within the central nervous system, sporadic Parkinson's disease does not begin in the spinal cord. In addition: (1) α-Synuclein-immunoreactive axons clearly predominated over Lewy bodies throughout the spinal cord and were visible in medial and anterior portions of the anterolateral funiculus. Their terminal axons formed dense α-synuclein-immunoreactive networks in the gray matter and were most conspicuous in the lateral portions of layers 1, 7, and in the cellular islands of layer 9. (2) Notably, this axonopathy increased remarkably in density from cervicothoracic segments to lumbosacral segments of the cord. (3) Topographically, it is likely that the spinal cord α-synuclein immunoreactive axonal networks represent descending projections from the supraspinal level setting nuclei (locus coeruleus, lower raphe nuclei, magnocellular portions of the reticular formation). (4) Following the appearance of the spinal cord axonal networks, select types of projection neurons in the spinal cord gray matter displayed α-synuclein-immunoreactive inclusions: chiefly, nociceptive neurons of the dorsal horn in layer 1, sympathetic and parasympathetic preganglionic neurons in layer 7, the cellular pools of α-motoneurons in layer 9, and the smaller motoneurons in Onuf's nucleus in layer 9 (ventral horn). The spinal cord lesions may contribute to clinical symptoms (e.g., pain, constipation, poor balance, lower urinary tract complaints, and sexual dysfunction) that occur during the premotor and motor phases of sporadic Parkinson's disease.

Nonmotor outcomes in Parkinson's disease: is deep brain stimulation better than dopamine replacement therapy?

Nonmotor symptoms are an integral part of Parkinson's disease and cause significant morbidity. Pharmacological therapy helps alleviate the disease but produces nonmotor manifestations. While deep brain stimulation (DBS) has emerged as the treatment of choice for motor dysfunction, the effect on nonmotor symptoms is not well known. Compared with pharmacological therapy, bilateral subthalamic nucleus (STN)-DBS or globus pallidum interna (GPi)-DBS has significant beneficial effects on pain, sleep, gastrointestinal and urological symptoms. STN-DBS is associated with a mild worsening in verbal fluency while GPi-DBS has no effect on cognition. STN-DBS may improve cardiovascular autonomic disturbances by reducing the dose of dopaminergic drugs. Because the motor effects of STN-DBS and GPi-DBS appear to be similar, nonmotor symptoms may determine the target choice in surgery of future patients.

Cognitive impairment and dementia in Parkinson's disease: clinical features, diagnosis, and management

Parkinson’s disease (PD) is a common, disabling, neurodegenerative disorder. In addition to classical motor symptoms, non-motor features are now widely accepted as part of the clinical picture, and cognitive decline is a very important aspect of the disease, as it brings an additional significant burden for the patient and caregivers. The diagnosis of cognitive decline in PD, namely mild cognitive impairment (MCI) and dementia, can be extremely challenging, remaining largely based on clinical and cognitive assessments. Diagnostic criteria and methods for PD dementia and MCI have been recently issued by expert work groups. This manuscript has synthesized relevant data in order to obtain a pragmatic and updated review regarding cognitive decline in PD, from milder stages to dementia. This text will summarize clinical features, diagnostic methodology, and therapeutic issues of clinical decline in PD. Relevant clinical genetic issues, including recent advances, will also be approached.

Association of UDP-glucuronosyltransferase 1A9 polymorphisms with adverse reactions to catechol-O-methyltransferase inhibitors in Parkinson's disease patients

PURPOSE

To investigate the association between adverse reactions to catechol-O-methyltransferase (COMT) inhibitors and the UDP-glucuronosyltransferase 1A9 genotypes UGT1A9*1b and UGT1A9*3a, which were previously identified in individual cases of COMT inhibitor-induced toxicity.

METHODS

The study included 52 Parkinson's disease (PD) patients on COMT inhibitors without evidence of adverse reactions and 11 PD patients who had been withdrawn from COMT inhibitors due to adverse reactions. UGT1A9*1b was identified by direct sequencing of the PCR amplification of the gene and UGT1A9*3a was assayed by real-time PCR.

RESULTS

The frequency of the *3a/*3a and *1/*3a genotype variants was 45.5 % in subjects with adverse reactions and 21.1 % in subjects without adverse reactions [overall UGT1A9*3a allele frequency 27.3 vs. 11.5 %, P = 0.087; odds ratio (OR) 2.87, 95 % confidence interval (CI) 0.94-8.77]. The frequency of genotype combinations leading to low glucuronosyltransferase activity (*3a/*3a irrespective of *1b or *1/*3a and *1/*1b) was 5.8 % in subjects without adverse reactions and 36.4 % in subjects with adverse reactions (P = 0.014; OR 9.33, 95 % CI 1.71-50.78).

CONCLUSIONS

In PD patients UDP-glucuronosyltransferase 1A9 genotypes are associated with adverse reactions to COMT inhibitors, leading to treatment withdrawal. UDP-glucuronosyltransferase 1A9 genotyping may be a screening and/or diagnostic test to assist individualized treatments with COMT inhibitors.