A 12-week, open trial of donepezil hydrochloride in patients with multiple sclerosis and associated cognitive impairments

Comfort care in severely disabled multiple sclerosis patients

Comfort may be considered as the material aspect of well-being, and its limitation, defined as discomfort, exacerbates both the patient's and caregivers' difficulties. Discomfort results from the interaction of a patient's environment, treatment, and from the nature and severity of elementary deficits, such as spasticity, ranges of motion, pain, postural disorders, motor deficit and fatigue, bladder problems, insufficient ventilatory control, and also psychological difficulties. Although discomfort reduction may represent a major challenge in disabled persons, discomfort is usually underestimated in the assessment of deficiencies, disabilities, handicap, and even in quality of life (QOL) estimations. In this paper, we explain why discomfort may be a crucial problem in severe multiple sclerosis (MS) and argue for a systematic assessment of discomfort in the follow-up of the disease, especially in the following domains: dressing, washing, maintaining posture in a wheelchair and bed, food intake, mastication and swallowing, bowel control, urinary and feces emission, and also sexual life. The way to enhance comfort in MS patients is then analyzed.

The neuropsychiatry of multiple sclerosis

This review describes the many neuropsychiatric abnormalities associated with multiple sclerosis (MS). These may be broadly divided into 2 categories: disorders of mood, affect, and behaviour and abnormalities affecting cognition. With respect to the former, the epidemiology, phenomenology, and theories of etiology are described for the syndromes of depression, bipolar disorder, euphoria, pathological laughing and crying, and psychosis attributable to MS. The section discussing cognition reviews the prevalence and nature of cognitive dysfunction, with an emphasis on abnormalities affecting multiple domains of memory, speed of information processing, and executive function. The detection, natural history, and cerebral correlates of cognitive dysfunction are also discussed. Finally, treatment pertaining to all these disorders is reviewed, with the observation that translational research has been found wanting when it comes to providing algorithms to guide clinicians. Guidelines derived from general psychiatry still largely apply, although they may not always be most effective in patients with neurologic disorders. The importance of future research addressing this imbalance is emphasized, for neuropsychiatric sequelae add significantly to the morbidity associated with MS.

The cholinesterase inhibitors

Dementia is a serious and growing problem that presents enormous burdens to patients, their families, and national healthcare systems throughout the world. In the United States, there are currently two classes of psychopharmacologic agents approved for the treatment of Alzheimer's disease: the cholinesterase inhibitors, which are approved for use in patients with mild to moderate disease, and memantine, an N-methyl-D-aspartate (NMDA) receptor antagonist, which is approved for treatment of moderate to severe illness. Three cholinesterase inhibitors are in general clinical use, each of which has a distinct pharmacokinetic, pharmacodynamic, and side-effect profile. In addition, there is growing research and clinical evidence of the effectiveness of the cholinesterase inhibitors in patients who are in the more advanced stages of Alzheimer's dementia as well as in patients with other forms of dementia.

Update on Alzheimer drugs (donepezil)

BACKGROUND

Several clinical trials have been conducted over a period of many years reporting the benefits of donepezil for Alzheimer disease (AD) patients.

REVIEW SUMMARY

Randomized, double-blind, placebo-controlled stud-ies of 3-6 months' duration have demonstrated significant benefits for 5mg/D and 10 mg/D of donepezil compared with placebo. The results include benefits for cognition, activities of daily living, and abnormal behaviors associated with AD. The benefits are independently detectable by clinicians based upon direct patient assessment with input from a caregiver. Populations studied include mild-to-moderate AD patients, moderate-to-severe AD patients, nursing home patients, and outpatients. Open label studies that took place after the double-blind phase and 1-year double-blind, placebo-controlled trials demonstrated that benefits persist for more than a year. Adverse event (AE) profiles, generated in studies that used a 1-week forced dose titration, show a low incidence of primarily cholinegic AEs such as nausea and diarrhea. There are no significant laboratory AEs or drug interactions. Recent studies have assessed the benefits of donepezil inpatients with ischemic vascular dementia, mild cognitive impairment, and other cognitive disorders.

CONCLUSIONS

Donepezil benefits AD patients by improving, stabilizing, or retarding decline of the cognitive, functional, and possibly behavioral features of the disease. The duration of benefits is not known but extends beyond 1 year. The drug is safe and well tolerated.

Screening for multiple sclerosis cognitive impairment using a self-administered 15-item questionnaire

Since there is a need for cost-effective screening techniques to identify neuropsychological impairment in multiple sclerosis (MS) patients, and because existing methods require cognitive testing with subsequent interpretation by a neuropsychologist, a brief self-report procedure was developed to screen for neuropsychological impairment in MS. In the first phase of the study, a pool of 80 items was generated based on a literature review and consultation with healthcare professionals. The set was reduced to 15 via Rasch analysis. Using these items, a brief (five minute) MS Neuropsychological Screening Questionnaire (MSNQ), including patient- and informant-report forms, was composed. In phase II, 50 MS patients and their caregivers completed the MSNQ. A comprehensive neuropsychological test battery was also administered. Analyses covered the reliability of the MSNQ and correlations between both patient- and informant-report scores and objective neuropsychological testing. Cronbach's alpha coefficients were 0.93 and 0.94 for the patient- and informant-report forms, respectively, and both forms of the test were strongly correlated with a more general cognitive complaints questionnaire. The patient MSNQ form correlated significantly with measures of depression but not with objective tests of cognitive function. In contrast, the informant form was correlated with patient cognitive performance but not depression. A cut-off score of 27 on the informant form of the MSNQ optimally separated patients based on a neuropsychological summary score encompassing measures of processing speed and memory. There were two false-negatives and one false-positive, giving the test a sensitivity of 0.83 and a specificity of 0.97. It is concluded, therefore, that this self-administered neuropsychological screening test is reliable and predicts neuropsychological impairment in MS patients with a reasonable degree of accuracy.

Donepezil for memory dysfunction in schizophrenia

A case is reported of a 54-year-old female patient with schizophrenia and cognitive impairment. Her memory dysfunction improved following the addition of donepezil to quetiapine. The possible implications for future studies are reviewed.

Cognitive dysfunction in multiple sclerosis: natural history, pathophysiology and management

Cognitive dysfunction is a major cause of disability in patients with multiple sclerosis (MS). The prevalence of cognitive dysfunction is estimated at 45 to 65%. Natural history studies suggest that once cognitive dysfunction develops in a patient with MS, it is not likely to remit. Unlike physical disability in MS, cognitive disability correlates weakly with T2 lesion burden on brain magnetic resonance imaging (MRI). More robust correlations exist with magnetisation transfer imaging and MRI measures of brain atrophy. Patients with MS who have cognitive impairment most commonly display deficits in the cognitive domains of memory, learning, attention and information processing. In diagnosing cognitive dysfunction in a patient with MS, it is important first to recognise and treat the common comorbidities of fatigue and depression. The first step in the treatment of cognitive dysfunction is to delay disease progression, and there are currently five such disease-modifying agents approved for the treatment of MS (two preparations of interferon-beta-1a, interferon-beta-1b, glatiramer acetate and mitoxantrone). Nonpharmacological measures, such as cognitive rehabilitation, occupational therapy and psychotherapy, are the mainstays of symptomatic treatment. Pharmacological symptomatic therapy centres on the treatment of comorbid fatigue and depression. There are currently no effective pharmacological agents approved as symptomatic therapy of cognitive dysfunction in MS.

Cognitive impairments in multiple sclerosis: a review

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS). Cognitive impairment (CI) may develop at any time during the course of the disease in the presence or absence of neurological disability. On the basis of comprehensive neuropsychological studies, there is now a consensus among investigators that 45 percent to 65 percent of MS patients suffer from some degree and form of cognitive difficulty. Features of CI include bradyphrenia; impaired attention, concentration and abstract reasoning; reduced manual speed and dexterity; deficits in memory retrieval; and language deficits in both the relapsing-remitting and progressive forms of MS. Impairments in all cognitive domains may result from the diffuse spread of microscopic pathology, although a preferential lobar distribution of plaques can present with a predominant deficit in the corresponding cognitive function. Nevertheless, the severity of CI best correlates with total microscopic and macroscopic disease burden of the brain as defined by recently developed magnetic resonance imaging (MRI) sequences. A disruption of connecting intercortical and subcortical pathways is likely to be the main cause of metabolic and functional abnormalities in neurons. However a direct toxic effect of soluble inflammatory products may also compromise neuronal function and survival. Early treatment of MS with interferons and copaxone can prevent or delay the onset of both neurological and cognitive disabilities by reducing the inflammatory activity and damage in the CNS. Until more powerful neuroprotective agents become available, simple neuropsychological screening and cognitive rehabilitation for memory and language impairments will remain important components in the care of MS patients.

Donepezil for Alzheimer's disease: pharmacodynamic, pharmacokinetic, and clinical profiles

Donepezil was developed in order to overcome the disadvantages of physostigmine and tacrine. Its use is based on the cholinergic hypothesis. Donepezil is a piperidine-based, reversible acetylcholinesterase inhibitor, that is chemically unrelated to other cholinesterase inhibitors. It was developed for the symptomatic treatment of Alzheimer's disease (AD). Donepezil is highly selective for acetylcholinesterase with a significantly lower affinity for butyrylcholinesterase, which is present predominantly in the periphery. Phase I and II clinical trials demonstrated donepezil's favorable pharmacokinetic, pharmacodynamic and safety profile. There is no need to modify the dose of donepezil in the elderly or in patients with renal and hepatic failure. Pivotal phase-III trials in the US, European countries, and Japan showed that donepezil significantly improved cognition and global function in patients with mild to moderate AD. In long-term trials, donepezil maintained cognitive and global function for up to 1 year prior to the resumption of gradual deterioration. Donepezil is generally well tolerated; most of its adverse events are mild, transient and cholinergic in nature. Donepezil produces no clinically significant changes in laboratory parameters, including liver function. The drug is approved for the treatment of mild to moderate Alzheimer's disease, but donepezil therapy does not have to be discontinued if a patient continues to deteriorate. Possible new indications for donepezil in psychiatric and neurologic diseases, other than AD, include dementia with Lewy bodies, brain injury, attention deficit hyperactivity, multiple sclerosis, Down's syndrome, delirium, mood disorders, Huntington's disease and sleep disorders.

Donepezil and related cholinesterase inhibitors as mood and behavioral controlling agents

Acetylcholinesterase inhibitors (ChEIs) enhance neuronal transmission by increasing the availability of acetylcholine in muscarinic and nicotinic receptors. This effect is believed to be responsible for the beneficial and protective effects of ChEIs on cognition in patients with Alzheimer's disease (AD). Effects of ChEIs on mood and behavior have also been reported. Earlier observations were limited by the exclusive availability of intravenous forms of administration, the short half-life of the formulations, and the high frequency of peripheral side effects. The introduction, in recent years, of better tolerated and less invasive compounds has rekindled the interest in cholinergic central nervous system mechanisms and has given rise to studies in areas other than cognition. The ChEI donepezil has been involved in the largest number of studies and positive reports. Preliminary observations suggest the possible value of ChEIs in the management of behavioral dysregulation, apathy, irritability, psychosis, depression, mania, tics, and delirium and in the diagnosis of depression, panic, and personality disorders.