Effects of methylphenidate on cognition and apathy in normal pressure hydrocephalus: a case study and review

Recent Advances in Rational Diagnosis and Treatment of Normal Pressure Hydrocephalus: A Critical Appraisal on Novel Diagnostic, Therapy Monitoring and Treatment Modalities

BACKGROUND

Normal pressure hydrocephalus (NPH) is a critical brain disorder in which excess Cerebrospinal Fluid (CSF) is accumulated in the brain's ventricles causing damage or disruption of the brain tissues. Amongst various signs and symptoms, difficulty in walking, slurred speech, impaired decision making and critical thinking, and loss of bladder and bowl control are considered the hallmark features of NPH.

OBJECTIVE

The current review was aimed to present a comprehensive overview and critical appraisal of majorly employed neuroimaging techniques for rational diagnosis and effective monitoring of the effectiveness of the employed therapeutic intervention for NPH. Moreover, a critical overview of recent developments and utilization of pharmacological agents for the treatment of hydrocephalus has also been appraised.

RESULTS

Considering the complications associated with the shunt-based surgical operations, consistent monitoring of shunting via neuroimaging techniques hold greater clinical significance. Despite having extensive applicability of MRI and CT scan, these conventional neuroimaging techniques are associated with misdiagnosis or several health risks to patients. Recent advances in MRI (i.e., Sagittal-MRI, coronal-MRI, Time-SLIP (time-spatial-labeling-inversion-pulse), PC-MRI and diffusion-tensor-imaging (DTI)) have shown promising applicability in the diagnosis of NPH. Having associated with several adverse effects with surgical interventions, non-invasive approaches (pharmacological agents) have earned greater interest of scientists, medical professional, and healthcare providers. Amongst pharmacological agents, diuretics, isosorbide, osmotic agents, carbonic anhydrase inhibitors, glucocorticoids, NSAIDs, digoxin, and gold-198 have been employed for the management of NPH and prevention of secondary sensory/intellectual complications.

CONCLUSION

Employment of rational diagnostic tool and therapeutic modalities avoids misleading diagnosis and sophisticated management of hydrocephalus by efficient reduction of Cerebrospinal Fluid (CSF) production, reduction of fibrotic and inflammatory cascades secondary to meningitis and hemorrhage, and protection of brain from further deterioration.

Nonsurgical therapy for hydrocephalus: a comprehensive and critical review

Pharmacological interventions have been tested experimentally and clinically to prevent hydrocephalus and avoid the need for shunting beginning in the 1950s. Clinical trials of varied quality have not demonstrated lasting and convincing protective effects through manipulation of cerebrospinal fluid production, diuresis, blood clot fibrinolysis, or manipulation of fibrosis in the subarachnoid compartment, although there remains some promise in the latter areas. Acetazolamide bolus seems to be useful for predicting shunt response in adults with hydrocephalus. Neuroprotection in the situation of established hydrocephalus has been tested experimentally beginning more recently. Therapies designed to modify blood flow or pulsation, reduce inflammation, reduce oxidative damage, or protect neurons are so far of limited success; more experimental work is needed in these areas. As has been recommended for preclinical studies in stroke and brain trauma, stringent conditions should be met for preclinical studies in hydrocephalus.

Apathy, ventriculomegaly and neurocognitive improvement following shunt surgery in normal pressure hydrocephalus

INTRODUCTION

Apathy - impaired motivation and goal-directed behaviour - is a common yet often overlooked symptom in normal pressure hydrocephalus (NPH). Caudate atrophy often yields apathetic symptoms; however, this structural and functional relationship has not yet been explored in NPH. Additionally, little is known about the relationship between apathy and post-shunt cognitive recovery.

METHODS

This audit investigated whether apathetic symptoms improve following shunt surgery in NPH, and whether this relates to cognitive response. In addition, we assessed the relationship between ventriculomegaly and apathy using the bicaudate ratio. Twenty-two patients with NPH completed the Mini-Mental State Examination (MMSE), the Apathy Evaluation Scale (AES) and the Geriatric Depression Scale (GDS) before and 3-9 months after shunt surgery. Pre-operative ventriculomegaly was correlated with pre-operative AES and GDS scores. Difference scores (post-shunt minus baseline values) for AES and GDS were correlated with cognitive outcome.

RESULTS

Greater pre-operative ventriculomegaly was associated with increased level of apathy and depression. A reduction in apathetic symptoms following shunt surgery was associated with improved performance on the MMSE.

CONCLUSIONS

Apathy may be indicative of a greater degree of subcortical atrophy in NPH and may relate to functional outcome.

Psychiatric symptoms are present in most of the patients with idiopathic normal pressure hydrocephalus

Normal pressure hydrocephalus (NPH) is characterized by gait disturbance, dementia and/or urinary incontinence associated with dilation of ventricular system with normal opening cerebrospinal fluid pressure. Wide scientifical evidence confirms association between NPH and psychiatric symptoms. We selected 35 patients with idiopathic normal pressure hydrocephalus from January 2010 to January 2012 in a Brazilian tertiary hospital and performed a formal psychiatric evaluation to identify psychiatric disorders. Psychiatric disorders were present in 71% of these patients, especially anxiety, depression and psychotic syndromes. NPH patients may develop symptoms with frontal dominance, such as personality changes, anxiety, depression, psychotic syndromes, obsessive compulsive disorder, Othello syndrome; shoplifting and mania. Unusual appearances of NPH symptoms may hinder early diagnosis and consequently proper treatment.

The ethics of elective psychopharmacology

Pharmacological cognitive enhancers (PCEs) are used to improve cognitive functions, such as attention, learning, memory and planning in patients with impairments in cognition resulting from traumatic brain injury (TBI) or from neuropsychiatric disorders such as Alzheimer's disease (AD), mild cognitive impairment, schizophrenia, and attention deficit hyperactivity disorder (ADHD). Moreover, PCEs have been shown to improve cognition in healthy volunteers with no psychiatric disorders. This article describes the rationale behind the need for their use in neuropsychiatric patients and illustrates how PCEs can ameliorate cognitive impairments, improve quality of life and wellbeing, and therefore reduce the economic burden associated with these disorders. We also describe evidence that PCEs are being used as cognitive enhancers by healthy people. Crucially, as the lifestyle use of these drugs becomes very popular in the healthy population, a final aim is to present an overview of the current and future neuroethical considerations of enhancing the healthy brain. As information regarding their actual use, benefits and harms in various healthy populations is currently lacking, we propose research that aims to obtain relevant empirical data, monitor the short- and long-term effectiveness and side-effects, and initiate accurate surveys to determine current patterns and quantity of usage of PCE drugs by healthy people. Furthermore, in order to instigate a dialogue between neuroethics and neuropsychopharmacology, we urge scientists to explore and communicate the social and ethical implications of their research to the public. Finally, we discuss and highlight other means of enhancing cognition in both patients and healthy adults, including education and physical exercise.

Treatment of Apathy in Huntington's Disease and Other Movement Disorders

OPINION STATEMENT

Apathy is one of the most prevalent neurobehavioral symptoms in Huntington's disease (HD), occurring in approximately 70% of the symptomatic HD population. Apathy scores in patients with HD are highly correlated with duration of illness, suggesting that apathy is an inevitable consequence of advanced disease. Although less distressing than symptoms like depression and less disruptive than irritability or aggression, apathy has a considerable adverse impact on those affected with HD because it leads to a decrease of the goal-directed behaviors that contribute much to the day-to-day quality of life. As a neuropsychiatric syndrome, apathy is also common in patients with other neuropsychiatric disorders such as Parkinson's disease, traumatic brain injury, cerebrovascular accident, dementia, and other neurodegenerative conditions. The nosologic status of apathy and lack of a clear definition has probably contributed to the paucity of therapeutic evidence in this area. Several different scales are available to measure apathy, including the Apathy Evaluation Scale, Apathy Inventory, Lilles Apathy Rating Scale, and the apathy items from the Unified HD Rating Scale, the Problem Behaviours Assessment for HD, and the Neuropsychiatric Inventory, but all are based on slightly different definitions of apathy, so the scores obtained may not be directly comparable. Assessment may also be complicated by overlap between the manifestations of apathy and other complications of HD such as depression, so the identification and treatment of these comorbid conditions is important. No adequate evidence currently supports any specific pharmacologic or psychological intervention for apathy in HD. Evidence can only be extrapolated from interventional studies done in other basal ganglia disorders such as Parkinson's disease or other neurodegenerative disorders such as dementia. The neurobiology of apathy points towards three areas of functional connectivity: connections between the dorsolateral prefrontal cortex (PFC) and basal ganglia, orbitomedial PFC and basal ganglia, and dorsomedial PFC and basal ganglia. Pharmacologic interventions such as cholinesterase inhibitors, the dopaminergic antidepressant bupropion, amantadine, levodopa, bromocriptine, methylphenidate, and atypical antipsychotics have all been tried in other neurodegenerative disorders, but not in HD. Psychosocial interventions such as cognitive stimulation therapy and multisensory stimulation, which have been used in patients with dementia, have not been properly studied in HD. Individualized treatment should be considered, using a combination of methods, as there is no evidence to support one particular type of treatment. Multidisciplinary input, environmental modifications, improved psychosocial support, and psychoeducation programs designed to help caregivers to understand and compensate for the deficits caused by this symptom may all have a role to play in the treatment of apathy.

The role of the neurologist in the longitudinal management of normal pressure hydrocephalus

BACKGROUND

Since normal pressure hydrocephalus (NPH) was first described in 1965, neurologists have been involved in the initial diagnostic evaluation for it but have rarely followed patients specifically to monitor response to therapy after shunt surgery.

REVIEW SUMMARY

The potential role for the neurologist in the longitudinal management of NPH has broadened, partly because of improvement in the tools used to diagnose and treat NPH and partly because of progress in understanding how NPH mimics and interacts with other common disorders of the elderly. The interplay of Alzheimer dementia, vascular dementia, Parkinson disease, and spinal stenosis with NPH presents the clinician with a patient profile that may be challenging to assess. Neurologists also face a broad differential spectrum of less common neurologic diseases that may present with similar signs (including ventriculomegaly) and symptoms; these diseases include frontotemporal dementia, progressive supranuclear palsy, Lewy body disease, corticobasal degeneration, Huntington disease, spongiform encephalopathy, and multiple-system atrophy.

CONCLUSIONS

The neurologist is in a unique position to differentiate NPH from alternative diagnoses, to suggest management strategies for patients with concomitant NPH and another neurologic disorder, and to participate in longitudinal management of NPH.

The role of dopamine in symptoms and treatment of apathy in Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is characterized by a number of serious and debilitating behavioral and psychological symptoms of dementia (BPSD). The most common of these BPSD is apathy, which represents a major source of morbidity and premature institutionalization in the AD population. Many studies have identified discrete changes to the dopaminergic (DAergic) system in patients with AD. The DAergic system is closely related to the brain reward system (BRS) and some studies have suggested that dysfunction in the DAergic system may account for symptoms of apathy in the AD population.

METHOD

Changes to the dopamine (DA) system in AD will be reviewed, and evidence supporting the involvement of the DAergic system in the development of apathy will be examined. Additionally, some pharmacological interventions with DA activity have been identified. The utility of these treatments in the AD population will be reviewed, with a focus on apathy as an outcome.

RESULTS

Evidence presented in this review suggests that DA dysfunction in discrete brain areas is an important correlate of apathy in AD and that the DAergic system may be a rational target for pharmacological treatment of apathy.

Methylphenidate for the treatment of Parkinson disease and other neurological disorders

Methylphenidate (MPH) is a central nervous system stimulant derived from an amphetamine and acts as a potent inhibitor of catecholamine reuptake and increases dopamine levels in the brain. Methylphenidate is widely used for the treatment of children and adults with attention deficit hyperactivity disorder. Because the dopaminergic system is critical to the pathological process in Parkinson disease (PD), it has been suggested that MPH, which increases dopaminergic stimulation at the postsynaptic receptor level, may provide symptomatic relief in PD patients. This article reviews those studies that have evaluated the potential of MPH to treat the motor and cognitive aspects of PD, summarizes the evidence for clinical use in other neurological diseases, and briefly reviews the physiological mechanisms whereby MPH may bring about its therapeutic effects. Methylphenidate does seem to be useful for ameliorating cognitive, affective, and motor deficits in PD and in other neurological patients; however, additional studies are needed before MPH can be routinely prescribed as an adjunct therapy in these populations.

The neuropsychology of normal pressure hydrocephalus (NPH)

Normal pressure hydrocephalus (NPH) accounts for one of the few known forms of reversible dementia. Varied aetiology and clinical presentation contribute to difficulties with early or differential diagnoses, and delayed surgical treatment may be less efficacious. Clinical neuropsychology provides a means of determining a cognitive profile for NPH, assisting in differential diagnosis, tracking the disorder's progression and assessing the efficacy of treatment. This article will review possible applications of clinical neuropsychology and propose a clinical assessment protocol for NPH.

Methylphenidate for the treatment of depressive symptoms, including fatigue and apathy, in medically ill older adults and terminally ill adults

BACKGROUND

Depressive symptoms, fatigue, and apathy are common symptoms among medically ill older adults and patients with advanced disease, and have been associated with morbidity and mortality. Methylphenidate has been used to treat these symptoms because of its rapid effect. Despite the long history of methylphenidate use for the treatment of depressive symptoms, fatigue, and apathy, there is little definitive evidence to support its use.

OBJECTIVE

The aim of this paper was to review the efficacy and tolerability of methylphenidate in the treatment of depressive symptoms, fatigue, and apathy in medically ill older adults and adults receiving palliative care.

METHODS

English-language articles presenting systematic reviews, clinical trials, or case series describing the use of methylphenidate for the treatment of depressive symptoms, fatigue, or apathy in medically ill older adults or adults receiving palliative care were identified. The key words methylphenidate and either depressive, depression, fatigue, or apathy were used to search the Cochrane Database, MEDLINE, PsycINFO, and International Pharmaceutical Abstracts. Included articles addressed depressive symptoms, fatigue, or apathy in (1) older adults (generally, age > or =65 years), particularly those with comorbid medical illness; (2) adults receiving palliative care; and (3) adults with other chronic illnesses. I excluded articles regarding treatment of depression in healthy young adults; bipolar disorder and attention-deficit/hyperactivity disorder; and narcolepsy, chronic fatigue syndrome, and related disorders.

RESULTS

A total of 19 controlled trials of methylphenidate in medically ill older adults or patients in palliative care were identified. Unfortunately, their conflicting results, small sample sizes, and poor methodologic quality limited the ability to draw inferences regarding the efficacy of methylphenidate, although evidence of tolerability was stronger. The available evidence suggests possible effectiveness of methylphenidate for depressive symptoms, fatigue, and apathy in various medically ill populations.

CONCLUSION

In the absence of definitive evidence of effectiveness, trials of low-dose methylphenidate in medically ill adults with depression, fatigue, or apathy, with monitoring for response and adverse effects, are appropriate.