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Dive into the research topics where Gerard J. M. Walstra is active.

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Featured researches published by Gerard J. M. Walstra.


The Lancet | 2001

Effect of hydroxychloroquine on progression of dementia in early Alzheimer's disease: an 18-month randomised, double-blind, placebo-controlled study

Willem A. van Gool; Henry C. Weinstein; Philip Scheltens; Gerard J. M. Walstra

BACKGROUND Results of epidemiological studies, neuropathological observations, and in-vitro experiments all suggest that inflammatory mechanisms contribute to the destructive lesions in Alzheimers disease. We aimed to establish the effect of the anti-inflammatory drug hydroxychloroquine on the progression of dementia. METHODS We did a double-blind, parallel-group, multicentre trial in which we randomly assigned 168 patients with early Alzheimers disease to hydroxychloroquine (200 or 400 mg dependent on bodyweight), or placebo for 18 months. Outcome measures were related to activities of daily living, cognitive function, and behavioural abnormalities. Analysis was by intention to treat. RESULTS At 18 months, mean scores for the interview for deterioration in daily life in dementia in patients on hydroxychloroquine (22.6 [SD 11.4]) did not differ from those for patients on placebo (21.3 [10.5]). Also, mean scores on the cognitive subscale of the Alzheimers disease assessment scale were closely similar in hydroxychloroquine (26.4 [14.9]) and placebo (25.7 [14.3]) treated patients, as were behavioural changes, measured by the revised memory and behavioural problems checklist (36.3 [12.0] and 34.2 [12.4], respectively). Explorative analyses did not suggest any specific subgroup that benefited from hydroxychloroquine. The frequency and nature of serious adverse events and side-effects were much the same in both groups. 155 (92%) patients completed all assessments over the entire study. INTERPRETATION Anti-inflammatory treatment with hydroxychloroquine for 18 months does not slow the rate of decline in minimal or mild Alzheimers disease.


Journal of Neurology | 1996

Reversible dementia in elderly patients referred to a memory clinic.

Gerard J. M. Walstra; Saskia Teunisse; W.A. van Gool; H. van Crevel

Abstract Dementia has a reversible cause in some cases, and these should be diagnosed without over-investigating the many patients with irreversible disease. We prospectively studied the prevalence of reversible dementia in a memory clinic, determined the added value of investigations compared with clinical examination and assessed the outcome of treatment of potentially reversible causes by measuring (1) cognition, (2) disability in daily functioning, (3) behavioural changes and (4) caregiver burden. Two hundred patients aged 65 years and over were examined, using the CAMDEX-N. If they were demented, the probable cause was diagnosed clinically and confirmed or excluded by a standard set of investigations, which were done in all patients. Of the patients, 170 (mean age 79.2 years) were demented; 31 were treated for potentially reversible causes. At follow-up after 6 months, no patients showed complete reversal of dementia. Five patients improved on clinical impression, but only one on clinicial measurement. Thirty patients were cognitively impaired, but not demented; seven were treated. Judged clinically, three patients improved, but on assessment only one did so; she recovered completely. Blood tests often produced diagnostic results that were not expected clinically, but electroencephalography and computed tomography of the brain did not. None of the investigations had an effect on outcome of dementia after treatment. We conclude that in elderly patients referred to a memory clinic, the prevalence of reversible dementia is of the order of 1%, if outcome after treatment is assessed by a standardized measurement. We recommend blood tests in all patients, to detect not only metabolic causes of dementia but also co-morbidity possibly worsening the dementia. Other investigations can be performed on clinical indication. Clinical evaluation remains the mainstay of diagnosis in dementia.


Journal of Neurology | 1996

Dementia and subnormal levels of vitamin B12: effects of replacement therapy on dementia.

Saskia Teunisse; Anna E. Bollen; Willem A. van Gool; Gerard J. M. Walstra

Routine determination of serum vitamin B12 levels is generally recommended as part of the screening of demented patients, based on the notion that vitamin B12 deficiency is one of the causes of reversible dementia. We studied the effects of vitamin B12 replacement therapy in a prospective longitudinal study at a memory clinic, with special emphasis on assessment of severity of dementia: not only cognitive deterioration, but also disability in the activities of daily life, behavioural problems, and the burden experienced by the caregiver were examined using instruments of proven validity. In a series of 170 consecutive patients with dementia, subnormal serum vitamin B12 levels were found in 26 cases (15%); all but one fulfilled diagnostic criteria for possible Alzheimers disease. Cobalamin supplementation was given to all patients and the effect was evaluated after 6 months. When the size and pattern of individual change scores, and the mean change scores on all instruments were taken into account, functioning after replacement therapy was not improved. When change scores of treated patients were compared with those of patients with Alzheimers disease (n = 69), vitamin B12 replacement did not result in slowing of the progression of dementia. Contrary to widely accepted beliefs, subnormal serum vitamin B12 levels are not a (quantitatively) important cause of reversible dementia.


Dementia and Geriatric Cognitive Disorders | 1998

Predicting Survival in Patients with Early Alzheimer’s Disease

Jules J. Claus; Willem A. van Gool; Saskia Teunisse; Gerard J. M. Walstra; Vincent I. H. Kwa; Albert Hijdra; Bernard Verbeeten; J. Hans T.M. Koelman; Lo J. Bour; Bram W. Ongerboer de Visser

We investigated whether an index based on clinical features, electroencephalogram and computed tomography is useful to predict survival in early Alzheimer’s disease. One hundred and sixty-three consecutively referred patients to an outpatient memory clinic and first diagnosed with Alzheimer’s disease (105 ‘probable’ and 58 ‘possible’, NINCDS-ADRDA criteria) were studied and outcome measure was death. Cox proportional hazards regression analysis and Kaplan-Meier survival curves were used to investigate relations between baseline parameters and survival. Eighty-four patients (51.5%) died during the follow-up period that extended to 5.8 years, with a median duration of survival after entry of 4.3 years. Baseline factors that were statistically significant and independently related to increased risk of mortality were high age, male sex, poor cognitive function as measured with the CAMCOG, low alpha and beta power on electroencephalogram, and temporoparietal atrophy on computed tomography scan. These results were independent of the diagnosis probable or possible Alzheimer’s disease. Based on the coefficients from the regression equation, we computed a survival index for each patient and we constructed three groups according to tertiles of this index. After 5.2 years of follow-up, survival curves showed a low mortality group with 81.7% patients alive (median survival at least 5.7 years), an intermediate mortality group with 35.9% patients alive (median survival 3.8 years), and a high mortality group with no patients alive (median survival 2.3 years). Log rank tests were statistically significant for comparisons between all three groups. We conclude that an overall index combining demographic, cognitive, electroencephalogram and computed tomography features is a strong predictor of survival in early Alzheimer’s disease.


Journal of Neurology | 1995

Diagnosing Alzheimer's disease in elderly, mildly demented patients: the impact of routine single photon emission computed tomography

Willem A. van Gool; Gerard J. M. Walstra; Saskia Teunisse; Friso M. Van der Zant; Henry C. Weinstein; Eric A. van Royen

Based on the observation of bilateral temporoparietal hypoperfusion in Alzheimers disease (AD), single photon emission computed tomography (SPECT) is advocated by some as a powerful diagnostic tool in the evaluation of demented patients. We studied whether routine brain SPECT in elderly, mildly demented outpatients increases the a priori diagnostic sensitivity and specificity of a careful clinical examination.99mTc-HMPAO SPECT imaging was performed in 110 patients for a first evaluation for dementia. A semiquantitative measure of temporoparietal (TP) perfusion was calculated as the ratio of the activity in the temporoparietal cortex to activity in the cerebellum. A diagnosis of probable AD according to the McKhann criteria was made in 68 patients (mean age of 79.3 years) based on the results of a clinical examination, ancillary investigations and a 6-month follow-up. TP perfusion was significantly lower in AD patients than in 18 age-matched, non-demented controls. However, at a specificity of 89%, sensitivity was only 43% for detecting probable AD. The clinicians judged that SPECT had contributed to the final diagnosis in only 8% of the demented patients investigated. Routine brain SPECT in elderly, mildly demented outpatients does not contribute substantially to diagnostic accuracy after a careful clinical examination using current diagnostic criteria. Clinical guidelines have to be developed for the use of SPECT in patients with (suspected) dementia.


Journal of Clinical and Experimental Neuropsychology | 2013

Symptom validity testing in memory clinics: Hippocampal-memory associations and relevance for diagnosing mild cognitive impairment

Anne Rienstra; Paul F. C. Groot; Pauline E.J. Spaan; Charles B. L. M. Majoie; Aart J. Nederveen; Gerard J. M. Walstra; Jos F. M. de Jonghe; Willem A. van Gool; Sílvia Delgado Olabarriaga; Vladimir Korkhov; Ben Schmand

Patients with mild cognitive impairment (MCI) do not always convert to dementia. In such cases, abnormal neuropsychological test results may not validly reflect cognitive symptoms due to brain disease, and the usual brain–behavior relationships may be absent. This study examined symptom validity in a memory clinic sample and its effect on the associations between hippocampal volume and memory performance. Eleven of 170 consecutive patients (6.5%; 13% of patients younger than 65 years) referred to memory clinics showed noncredible performance on symptom validity tests (SVTs, viz. Word Memory Test and Test of Memory Malingering). They were compared to a demographically matched group (n = 57) selected from the remaining patients. Hippocampal volume, measured by an automated volumetric method (Freesurfer), was correlated with scores on six verbal memory tests. The median correlation was r = .49 in the matched group. However, the relation was absent (median r = −.11) in patients who failed SVTs. Memory clinic samples may include patients who show noncredible performance, which invalidates their MCI diagnosis. This underscores the importance of applying SVTs in evaluating patients with cognitive complaints that may signify a predementia stage, especially when these patients are relatively young.


Journal of Geriatric Psychiatry and Neurology | 1997

Symptomatic Treatment of Elderly Patients with Early Alzheimer's Disease at a Memory Clinic

Gerard J. M. Walstra; Saskia Teunisse; Willem A. van Gool; Hans van Crevel

It is widely accepted that excess disability (treatable coexisting physical disorders and psychiatric phenomena) is common in demented patients, and should be looked for carefully and treated properly, as it may result in improvement. This idea, however, does not state what investigations should be performed and what kind of improvement can be expected. Therefore, we studied prospectively in elderly outpatients with early Alzheimers disease the prevalence of excess disability, the results of medication treatment, and the added value of investigations for diagnosis, treatment, and outcome after clinical examination. Outcome was assessed clinically and clinimetrically (using instruments with regard to cognition, disability in daily functioning, behavior, and caregiver burden). Excess disability was present in 66% of patients. Medication treatment was effective with regard to target symptoms, but (partial) reversal of dementia did not occur. Only blood tests produced unexpected results with consequences for treatment and outcome. Positive treatment effects often resulted from clinical examination only. We recommend blood tests in all patients; other investigations can be performed on clinical indication.


Dementia and Geriatric Cognitive Disorders | 1998

Determinants of global clinical change assessment in patients with early Alzheimer's disease

J. J. Claus; Saskia Teunisse; Gerard J. M. Walstra; W.A. van Gool

Global clinical impression (GCI) of change is assumed to integrate aspects of both cognitive and noncognitive functioning. We evaluated 140 consecutive patients with probable (n = 90) and possible (n = 50) early Alzheimer’s disease at baseline and after 6 months with measurements of global cognitive function (CAMCOG), behavior, activities of daily living, and burden of the caregiver. After 6 months, both the clinician (GCI-clin) and the caregiver (GCI-care) rated clinical change on a 3-point scale (worse, no change, improved). Data were analyzed with multiple polychotomous logistic regression, adjusted for age and sex. Change in global cognitive function and GCI-care were significantly and independently related to GCI-clin, while changes in activities of daily living and in behavior were significantly and independently associated with GCI-care. The findings suggest a double dissociation. Change in cognition appears to be the major determinant of the clinician’s global impression but not change in behavioral and functional parameters, while global impression of the caregiver is primarily based on change in behavioral and functional measures but not on change in cognition.


Annals of Neurology | 1995

Concentrations of amyloid β protein in cerebrospinal fluid of patients with alzheimer's disease

W.A. van Gool; Gerard J. M. Walstra; P. A. Bolhuis; M. A. Kuiper; E.Ch. Wolters


JAMA Neurology | 1998

Quantitative spectral electroencephalography in predicting survival in patients with early Alzheimer disease

Jules J. Claus; Bram W. Ongerboer de Visser; Gerard J. M. Walstra; Albert Hijdra; Bernard Verbeeten; Willem A. van Gool

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Jules J. Claus

National Institutes of Health

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