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T Mendis

Publications and source records attributed to T Mendis.

15 recordsLinked to original sources
PubMed2000

Risperidone in the treatment of dopamine-induced psychosis in Parkinson's disease: an open pilot trial.

PURPOSE: To evaluate the safety and efficacy of risperidone in patients with Parkinson's disease (PD) who are experiencing significant dopamine-induced psychosis. PATIENTS AND METHODS: Seventeen patients (median age, 72 yrs) participated in this 12-week, open pilot study receiving 0.5 to 3 mg oral risperidone per day. Maintenance antiparkinsonian medication was continued throughout, although psychotropic medication was discontinued. EFFICACY RESULTS: Risperidone produced a substantial improvement in psychotic symptoms, shown on the mean total positive subscale score on the Positive and Negative Syndrome Scale (PANSS) by a 30% improvement (-3.1 decrease) after 1 week and a 66% improvement (-6.8 decrease) at end point. This improvement was most evident in the items delusions, hallucinatory behavior, and suspiciousness/persecution. Risperidone also achieved significant improvement from baseline in Clinical Global Impression (CGI)-severity and CGI-improvement (p < 0.001, Page test). Risperidone treatment did not adversely affect symptoms specific to Parkinson's disease, as assessed by the Unified Parkinson's Disease Rating Scale (UPDRS). SAFETY RESULTS: Sixteen patients reported at least one adverse event, but only two patients withdrew as a result of adverse events. No significant changes or clinically relevant abnormalities were observed in laboratory parameters or vital signs. CONCLUSION: Short-term use of risperidone (mean dosage, 1.1 mg per day) improves the psychopathology of patients with PD who have dopamine-induced psychosis without adversely affecting the symptoms of PD. Higher doses and long-term use were not addressed in this study and may be precluded by extrapyramidal side effects.

Adult↗
PubMed1999

EEG and the passive P300 in dementia of the Alzheimer type.

Quantitatively analyzed resting electroencephalographic (EEG) activity and P300 event-related potentials elicited with a passive tone sequence paradigm were examined in 30 patients with dementia of the Alzheimer type (DAT) and 15 age matched controls. Background electrical rhythms of DAT patients evidenced slowing as shown by increased absolute and relative amplitudes in slow frequency bands and decreased amplitudes in fast frequency bands (relative to controls). Electrical slowing was more evident in patients with higher clinical ratings of global intellectual deterioration. Passive P300 amplitude and latency did not differentiate patients and controls and were not related to severity of dementia.

Aged↗
PubMed1999

Management of Parkinson's disease a review of current and new therapies.

The management of Parkinson's disease has undergone recent changes with the advent of new therapies, both pharmacotherapy and surgery. Available interventions are discussed. Levodopa remains the mainstay of therapy. New drugs include the dopamine agonists and COMT inhibitors. New dopamine agonists which may have a levodopa "sparing effect;" it has been suggested that some of the drugs should be considered as first line treatments for newly diagnosed Parkinson's disease patients. We review roles of these drugs. The concept of neuroprotection in neurodegenerative disorders such as Parkinson's disease became popular in the mid 1980s and it is hoped that eventually therapy will be directed at slowing progression of the disease. A great deal more work needs to be done before a suitable agent is identified as being neuroprotective. Potential neuroprotective agents are reviewed. Surgical therapies for Parkinson's disease consisting of various forms of lesion surgery as well as stimulation procedures are reviewed. Complications of drug therapy include motor problems such as motor response fluctuations, as well as psychiatric complications including levodopa-induced psychosis. Atypical neuroleptic agents and ECT for psychiatric syndromes associated with Parkinson's disease are discussed. Algorithms for the management of early disease as well as the management of psychosis in Parkinson's disease are included. Treatment options for advanced disease are tabulated.

Antiparkinson Agents↗
PubMed1997

Treatment of Alzheimer's disease with sabeluzole: functional and structural correlates.

Sabeluzole, a new benzothiazole derivative, has been shown to be neurobiologically active preclinically and clinically appears to exert beneficial effects on memory. In this study, sabeluzole (5 or 10 mg twice daily vs. placebo) was investigated in patients with probable Alzheimer's disease over 1 year, with assessments of cognitive performance and structural changes. Cognitive performance was measured using the Alzheimer's Disease Assessment Scale periodically during treatment. Potential structural correlates in the frontal horn, caudate, third ventricle and hippocampal regions were examined by obtaining computerized tomographic (CT) images before and after treatment. Patients receiving sabeluzole evidenced greater stability than did placebo-treated patients in some cognitive measures. CT measures showed no significant changes from baseline, but some weak associations were found between relative preservation of cognitive function and smaller structural declines in the third ventricle and hippocampus. Cognitive outcome measures suggest that sabeluzole may have potential in slowing the cognitive deterioration of Alzheimer's disease. Furthermore, the method used to explore potential benefits on a morphologic level, although negative in this study, could yet have potential.

Aged↗
PubMed1996

Utility of clinical trial batteries in the measurement of Alzheimer's and Huntington's dementia.

Tests used as outcome measures in clinical trials of antidementia agents are not typically employed as part of diagnostic evaluations, and little information exists as to the sensitivity of these tests in terms of either differentiating demented patients from normal individuals or in distinguishing dementias of various types and etiologies. Sensitivity to mild dementia and sensitivity to impairment of various neuropsychological domains are, however, prerequisites for valid use of an instrument as an outcome measure in this context. The present study was undertaken to directly compare six different tests (three traditional psychometric tests and three clinical trial batteries) in terms of their sensitivity to detect and distinguish between mild dementia in patients with either Alzheimer's disease (n = 15) or Huntington's disease (n = 15), when compared to normal controls (n = 15). Tests included the Mattis Dementia Rating Scale, the Mini-Mental State Examination, the Wechsler Memory Scale-Revised, the Alzheimer's Disease Assessment Scale-Cognitive Subscale, the Computerized Drug Research (CDR) Cognitive Assessment System, and the Repeatable Battery for the Assessment of Dementia (RBAD). All of the tests were roughly equivalent in terms of their ability to discriminate normal subjects from mildly demented patients. Only the CDR and RBAD, however, were able to reliably discriminate between the two patient groups. The results are discussed in terms of the applicability of these tests as outcome measures for clinical trials in dementing disorders.

Adult↗
PubMed1995

Cognitive and quantified electroencephalographic correlates of cycloserine treatment in Alzheimer's disease.

Cycloserine acts as a potent and selective modulator of the N-methyl-D- aspartate (NMDA) receptor-associated glycine recognition site, which may be a possible mechanism for this compound's positive effects on memory formation and retrieval processes in animals. Studies in normal human volunteers have shown that cycloserine can have significant positive effects on cognitive processing in the elderly and can ameliorate memory deficits induced by subcutaneously administered scopolamine. Based on this profile, a double-blind, placebo controlled, parallel group (three drug dosages) study was conducted as part of a larger study to assess the efficacy and safety, as well as the cognitive and central nervous system (CNS) impact, of 6 months of cycloserine treatment in patients (N = 40) with probable dementia of the Alzheimer type (DAT). The Cognitive Drug Research Computerize Assessment System (CDR System) served as the primary outcome measure of efficacy. CNS activity was assessed using quantified electroencephalography (QEEG). Safety measures included adverse effects documentation and analysis of blood chemistry/hematology. Cycloserine proved to be a safe agent in this population at the doses given but failed to show any statistically significant effects in the areas of cognition and global clinical ratings and did not indicate significant CNS activity on QEEG. These findings suggest that cycloserine has no measurable therapeutic effect on Alzheimer's disease at the doses given.

Aged↗
PubMed1994

Symptomatic relief from treatment-induced psychosis in Parkinson's disease: an open-label pilot study with remoxipride.

Current treatment strategies for levodopa-induced psychosis in Parkinson's disease have had limited success. Remoxipride, a selective D2 receptor antagonist, was administered in an open label pilot study to seven parkinsonian patients exhibiting thought disorder. Symptoms improved significantly in six patients after treatment durations of 1-6 months and cleared completely in two individuals. One patient (at age 90 the oldest in the group) could not tolerate the compound due to significant motor deterioration, and the drug had to be discontinued after 1 week. In all remaining patients, no motor complications appeared, and therapeutic effects of remoxipride continued for up to 3 months after treatment cessation and have lasted for 2 years now in one individual. Further study of this compound in the context of treatment-induced psychosis in Parkinson's disease appears to be warranted.

Aged↗
PubMed1994

Neurotransmitter replacement therapy in Alzheimer's disease.

The relative success of symptomatic attenuation of motor dysfunction in Parkinson's disease with dopaminomimetics has spurred interest in neurotransmitter replacement therapy for treating Alzheimer's disease. While cholinergic dysfunction has been linked to various clinical parameters in Alzheimer's disease, cholinergic replacement, including precursor therapy, administration of direct-acting agonists and inhibition of enzymatic degradation has had only very modest success. The inhibition of enzymatic degradation has perhaps shown the most interesting results to date. However, conclusions with respect to efficacy continue to be controversial. Discussion continues about whether or not single transmitter replacement for Alzheimer's disease is a viable treatment approach. Deficiencies in central noradrenergic, serotonergic, GABAergic and perhaps dopaminergic neural transmission may also play a critical role in some of the clinical manifestations of Alzheimer's disease. In addition, certain neuropeptides, in particular somatostatin, may be important in this context. Several series of clinical trials are currently attempting to address these issues. Given the complexities of the pathophysiology of Alzheimer's disease, symptomatic relief may require multiple transmitter replacement and necessitate more definitive intercessions at the molecular biological level.

Aged↗
PubMed1986

Bilateral facial paralysis following ethylene glycol ingestion.

Bilateral facial weakness, diminished hearing and dysphagia developed in a patient with a large overdose of ethylene glycol. Our case and two others previously reported draw attention to the fact that cranial nerve dysfunction, especially bilateral facial palsy, may occur in addition to encephalopathy, coma and renal failure with ethylene glycol ingestion.

Adult↗
PubMed1979

Effect of benztropine on haloperidol-induced prolactin secretion.

The effect of benztropine on haloperidol-induced prolactin secretion was investigated in 10 normal male volunteers. Benztropine had no effect on basal prolactin secretion but significantly enhanced the increased induced by haloperidol. The magnitude of the enhancement, however, was relatively small. These data suggest that in man cholinergic mechanisms have no effect on basal prolactin secretion but exert a weak inhibitory effect under conditions of dopamine receptor blockade. Differences in intrinsic anticholinergic properties may account for some of the variations in potency of different neuroleptics in increasing circulating prolactin concentrations.

Adult↗