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PubMed1999

Neuropsychological deficits in Lyme disease patients with and without other evidence of central nervous system pathology.

A small percentage of Lyme patients develop mild to moderate encephalopathic symptoms months to years after diagnosis and treatment. Their symptoms typically include fatigue, memory loss, sleep disturbance, and depression. However, the etiology of this syndrome remains controversial. It is generally thought that Lyme patients with abnormal cerebral spinal fluid (CSF) have a neurological basis to their illness. To further examine this question, we compared Lyme patients with evidence of abnormal CSF, intrathecal antibody to Borrelia burgdorferi, elevated protein, or a positive polymerase chain reaction for B. burgdorferi DNA (n = 14); Lyme patients with normal CSF (n = 18); and healthy controls (n = 15) on a battery of neuropsychological and personality tests. Although both Lyme groups reported memory problems, only the Lyme group with abnormal CSF had measurable memory deficits. Both Lyme groups had higher depression scores than the normal control group, although depression was not correlated with memory scores. It appears that Lyme patients with abnormal CSF may have a neurological basis to their illness, whereas affective symptoms, common to many chronic disorders, may predispose other Lyme patients to the perception of cognitive dysfunction.

Adult↗

PubMed1994

Cognitive impairment in human chronic Chagas' disease.

UNLABELLED: We proposed to investigate subclinical cognitive impairment secondary to chronic Chagas' disease (CCD). No similar study was previously done. The neuropsychological performance of 45 chronic Chagasic patients and 26 matched controls (age, education place and years of residency in endemic area) was compared using the Mini Mental State Exam (MMSE), Weschler Memory Scale (WMS) and the Weschler Adult Intelligent Scale (WAIS). Non-parametric tests and Chi2 were used to compare group means and multivariate statistics in two way frequency tables for measures of independence and association of categorical variables with the disease. RESULTS: Chagasic patients showed lower MMSE scores (p < .004), poor orientation (p < .004), and attention (p < .007). Lower WMS MQ were associated with CCD (Chi2 5.9; p < .01; Fisher test p < .02). Lower WAIS IQ were associated with CCD (Chi2 6.3, p < .01; Fisher test p < .01) being the digit symbol (p < .03), picture completion (p < .03), picture arrangement (p < .01) and object assembly (p < .03) subtests the most affected. The impairment in non-verbal reasoning, speed of information processing, problem solving, learning and sequencing observed in chronic Chagas disease patients resembles the cognitive dysfunction associated with white matter disease.

Adult↗

PubMed2001

Changes in cognitive abilities over a 4-year period are unfavorably affected in elderly diabetic subjects: results of the Epidemiology of Vascular Aging Study.

OBJECTIVE: To compare 4-year changes in cognitive performance among elderly subjects according to category of fasting blood glucose (FBG) using American Diabetes Association criteria. RESEARCH DESIGN AND METHODS: Subjects without any detectable cognitive dysfunction were selected from the Epidemiology of Vascular Aging (EVA) Study, a cohort of community-dlwelling people aged 59-71 years at baseline. They were classified into glucose categories (normal, impaired fasting glucose [IFG], or diabetic) based on FBG values or known diabetes. Their cognitive abilities were assessed by a global test (Mini Mental Status Examination [MMSE]) and eight domain-specific tests, and they were reassessed 4 years later. Serious cognitive worsening was defined as a score evolution into the worst 15% of the sample's distribution of score differences (4-year score minus baseline score) for each test. RESULTS: At baseline, age-, sex-, and education-adjusted scores for all cognitive tests except one were similar across glucose categories. After 4 years, diabetic subjects had a lower performance on all tests except the MMSE, with differences reaching statistical significance on four tests. Adjusted odds ratios for serious worsening over 4 years in diabetic subjects, with reference to normal subjects, were >2 for four tests (P < 0.05) and bordering this value for two others (P < 0.09). Further adjustment for blood pressure or potential cognition-affecting substances (alcohol, tobacco, and medications) did not modify these results. CONCLUSIONS: Despite similar high initial cognitive function, diabetic subjects tended to have an unfavorable evolution of cognitive performance over 4 years compared with subjects who had normal glucose or IFG.

Aged↗

PubMed2005

Relationships between hyperglycemia and cognitive performance among adults with type 1 and type 2 diabetes.

OBJECTIVE: Hyperglycemia is a common event among patients with type 1 and type 2 diabetes. While the cognitive-motor slowing associated with hypoglycemia is well documented, the acute effects of hyperglycemia have not been studied extensively, despite patients' reports of negative effects. This study prospectively and objectively assessed the effects of hyperglycemia on cognitive-motor functioning in subjects' natural environment. RESEARCH DESIGN AND METHODS: Study 1 investigated 105 adults with type 1 diabetes (mean age 37 years and mean duration of diabetes 20 years), study 2 investigated 36 adults with type 2 diabetes (mean age 50 years and mean duration of diabetes 10 years), and study 3 investigated 91 adults with type 1 diabetes (mean age 39 years and mean duration of diabetes 20 years). Subjects used a hand-held computer for 70 trials over 4 weeks, which required them to complete various cognitive-motor tasks and then measure and enter their current blood glucose reading. RESULTS: Hyperglycemia (blood glucose >15 mmol/l) was associated with slowing of all cognitive performance tests (P < 0.02) and an increased number of mental subtraction errors for both type 1 and type 2 diabetic subjects. The effects of hyperglycemia were highly individualized, impacting approximately 50% of the subjects. CONCLUSIONS: Acute hyperglycemia is not a benign event for many individuals with diabetes, but it is associated with mild cognitive dysfunction.

Adult↗

PubMed2000

Dementia and depression in elderly medical inpatients.

The purpose of this study was to examine the prevalence and correlation of cognitive impairments, major depression, and depressive symptoms among elderly medical inpatients, and to compare the degree of depressive symptomatology as well as cognitive deterioration in possible vascular dementia and possible Alzheimer's disease. In a department of internal medicine, 100 (36 male, 64 female) 65-year-old or older patients were examined by a semistructured interview, and assessed by the Hachinski Ischemic Scale, the Hamilton Rating Scale for Depression (HDS), and the Modified Mini-Mental State (MMMS) Examination. In our total sample, the MMMS total score was (+/-SD) 76.0+/-15.5 and the HDS total score was (+/-SD) 12.0+/-6.1. Based on DSM-IV criteria, major depression was established in 11 patients. Deterioration of cognitive functions was seen in 66 patients; cognitive impairment was mild in 30 patients, moderate in 19, and severe in 17. Forty-six patients had mild depressive symptoms and 27had severe depressive symptoms. In summary, a high prevalence of cognitive dysfunction and depressive symptomatology was detected in our study, illustrating the importance of psychiatric care in elderly medical inpatients.

Aged↗

PubMed2004

[Blood pressure and related cognition among elderly residents in the community in Beijing - a 4-year longitudinal study].

OBJECTIVE: To investigate the association between blood pressure and related cognitive function with Mini-Mental State Examination (MMSE) in the elderly community residents in Beijing. METHODS: A selected sample of 60 years old and over from the communities was randomized ascertained to a longitudinal study in Beijing. The baseline data was produced in 1993, in which blood pressure, MMSE and a multidisciplinary questionnaire were involved. 4 years later in 1997, a similar procedure was repeated in 2079 elderly people whose MMSE scores were normal during the baseline study. RESULTS: The mean systolic blood pressure, diastolic blood pressure and MMSE score were 141.77 +/- 24.94 mm Hg, 81.76 +/- 12.08 mm Hg and 25.65 +/- 3.59 in baseline. The MMSE score was 23.24 +/- 5.63 in the follow-up study. Significant decline in cognition was defined as a decrease of 4 score and over during the 4-years study. The proportion of significant decline in cognition in the follow-up was larger when the systolic blood pressure or diastolic blood pressure having an increase in baseline data. Further stratified observation showed that factors as elderly with elevated blood pressure, under 75 years old from rural areas without diabetes mellitus or antihypertensive medication were more commonly seen in the ones with significant cognition decline. Increased incidence of cognitive decline was found in those with increased level of hypertension. This association was also seen in systolic blood pressure after adjustment of heart disease and cerebrovascular disease. CONCLUSIONS: In the 4-year longitudinal study, cognitive dysfunction might cause elevated baseline systolic and diastolic blood pressure in the elderly people whose baseline MMSE scores were normal.

Aged↗

PubMed2005

Hypertension and cognitive function. Blood pressure regulation and cognitive function: a review of the literature.

High blood pressure raises the risks of vascular dementia and cognitive dysfunction in older adults, by acting on the cerebral vasculature and directly on the brain itself. Clinical trials and observational studies have shown that treating hypertension to target (<140/90 mm Hg) not only lessens morbidity and mortality, but also improves quality of life and preserves cognitive function. Yet, only 34% of hypertensive Americans currently have their hypertension under control, despite widespread treatment. Although single drug therapy is effective in treating hypertension, most patients will require combination drug treatment. Combination therapy--typically a diuretic with an ACE inhibitor, an ARB, or a beta blocker--is appropriate for treatment of older patients, is well tolerated, and can effectively preserve cognitive function.

Aged↗

PubMedDate not supplied

[Sensitivity and specificity of a neuropsychological instrument in the evaluation of schizophrenia subtypes: a study with a Spanish speaking population].

INTRODUCTION: Cognitive impairment is a prominent feature of schizophrenia that correlates with functional outcome. In the clinical practice and research, there is a need to count on brief, reliable and standardized instruments to evaluate the cognitive profile in psychiatric, geriatric and neurological patients. There are only a few standardized and validated instruments with the Hispanic population, so the adaptation and validation of instruments become a high relevance issue. The Brief Neuropsychological Test in Spanish (NEUROPSI) is a brief neuropsychological battery evaluating a wide spectrum of cognitive functions and standardized with Spanish speaking population according to age and educational level. The purpose of the present study was to determine the sensitivity and specificity of this instrument for its clinical use in patients with schizophrenia, as well as in distinct subtypes of schizophrenic patients: positive, negative and mixed. METHODS: We studied a total sample of 60 subjects (30 patients with schizophrenia and 30 matched controls). Using the total score we found 87.5 % sensitivity and 92.8% specificity. A discriminant analysis using the 25 subtest scores of the NEUROPSI accurately classified 83.3 % of the sample. None of the control subjects was classified as patient. RESULTS: Classification by subtype showed 80 % of patients with negative symptoms, 90 % of patients with positive symptoms and 70 % of patients with mixed symptoms. CONCLUSIONS: The accurate diagnosis of cognitive dysfunction in schizophrenic patients could help in management as well as development of more specific pharmacological treatment for each schizophrenic subtype.

Adult↗

PubMed2005

A randomized controlled trial of dehydroepiandrosterone in postmenopausal women with fibromyalgia.

OBJECTIVE: Patients with fibromyalgia (FM) consistently have adrenal hyporesponsiveness and low dehydroepiandrosterone (DHEA) levels. DHEA is promoted for and used by patients with FM. We tested the efficacy and safety of DHEA supplementation in ameliorating the symptoms of FM. METHODS: In a double-blind crossover study, postmenopausal women with FM were randomized to DHEA supplementation (50 mg/day) or placebo for 3 months, with a one-month washout period in between. Patients were assessed monthly for well-being and pain and by medical evaluations at the beginning and the end of each treatment period. The primary outcome was well being; secondary outcomes were pain, fatigue, cognition, sexuality, functional impairment, depression, and anxiety. RESULTS: A total of 52 patients were randomized, 47 patients completed the DHEA treatment period, and 45 the placebo treatment period. After 3 months of treatment with 50 mg of DHEA, median DHEA sulfate blood levels had tripled, but there was no improvement in well-being, pain, fatigue, cognitive dysfunction, functional impairment, depression, or anxiety, nor in objective measurements made by physicians. Androgenic side effects (greasy skin, acne, and increased growth of body hair) were more common during the DHEA treatment period (p = 0.02). CONCLUSION: DHEA does not improve quality of life, pain, fatigue, cognitive function, mood, or functional impairment in FM.

Aged↗

PubMed1997

Obstructive sleep apnea and abnormal P300 latency topography.

This study was conducted to evaluate cognitive abnormalities in obstructive sleep apnea (OSA) using cognitive evoked potentials (P300), and to clarify if such cognitive dysfunction is related to the OSA itself or to the hypersomnolence in OSA. Subjects were administered a polysomnogram, auditory and visual P300 testing using 31 scalp electrodes, and the multiple sleep latency test. There were 40 normal subjects ages 26 to 75. Of 143 consecutive OSA patients ages 26 to 75, 56 had severe OSA (Respiratory Disturbance Index or RDI 40-80/h sleep) with objective somnolence (Mean Sleep Latency < 5 min). Thirty-three had severe OSA without objective somnolence. Fifty-four had profound OSA (RDI > 80/h sleep) with or without objective somnolence. The normals and the three OSA groups did not differ in age. Patients with profound OSA or with severe OSA without somnolence had longer visual P300 latency than normals. The groups also differed in visual P300 latency topography. OSA patients had significantly longer latencies frontally than normals. Thus, OSA, even in the absence of hypersomnolence, is associated with abnormalities in cognitive evoked potentials. Visual P300 latency at frontal electrodes seems to be a neurophysiological index of dysfunction in OSA that is independent of tests of sleepiness.

Adult↗

PubMed2002

Minimal neuropsychological assessment of MS patients: a consensus approach.

Cognitive impairment is common in multiple sclerosis (MS), yet patients seen in MS clinics and neurologic practices are not routinely assessed neuropsychologically. In part, poor utilization of NP services may be attributed to a lack of consensus among neuropsychologists regarding the optimal approach for evaluating MS patients. An expert panel composed of neuropsychologists and psychologists from the United States, Canada, United Kingdom, and Australia was convened by the Consortium of MS Centers (CMSC) in April, 2001. Our objectives were to: (a) propose a minimal neuropsychological (NP) examination for clinical monitoring of MS patients and research, and (b) identify strategies for improving NP assessment of MS patients in the future. The panel reviewed pertinent literature on MS-related cognitive dysfunction, considered psychometric factors relevant to NP assessment, defined the purpose and optimal characteristics of a minimal NP examination in MS, and rated the psychometric and practical properties of 36 candidate NP measures based on available literature. A 90-minute NP battery, the Minimal Assessment of Cognitive Function in MS (MACFIMS), emerged from this discussion. The MACFIMS is composed of seven neuropsychological tests, covering five cognitive domains commonly impaired in MS (processing speed/working memory, learning and memory, executive function, visual-spatial processing, and word retrieval). It is supplemented by a measure of estimated premorbid cognitive ability. Recommendations for assessing other factors that may potentially confound interpretation of NP data (e.g., visual/sensory/motor impairment, fatigue, and depression) are offered, as well as strategies for improving NP assessment of MS patients in the future.

Cognition Disorders↗

PubMed2000

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

Cognitive dysfunction occurs in up to 65% of patients with multiple sclerosis (MS), but there is no effective treatment for the symptoms. The authors conducted a 12-week, open-pilot study to assess the efficacy and tolerability of donepezil HCl administered in patients with MS and cognitive impairment. Seventeen patients at a long-term care facility with Mini-Mental State Examination scores of < or = 25 received 5 mg of donepezil HCl for a 4-week period, followed by 8 weeks of 10 mg of donepezil HCl. Cognitive, neurologic, functional, and behavioral assessments were conducted at baseline and at 4 and 12 weeks. Statistically significant improvement was observed in several cognitive domains including attention, memory, and executive functioning, as well as different aspects of behavior. These data suggest that donepezil HCl merits further study as a potentially viable treatment option for patients with cognitive impairment associated with MS.

Adult↗

PubMed2005

Risk factors for chronic insomnia following hospitalization.

AIM: This paper reports a study whose purpose was to determine whether there is an increase in the incidence of chronic insomnia following hospitalization and, if so, to identify patients at risk. BACKGROUND: The consequences of difficulty sleeping in hospital have received scant attention from clinicians or researchers. Implicit in this lack of interest is the assumption that difficulty in sleeping is a transient reaction to hospitalization that will resolve on discharge, an assumption not empirically supported. It has been argued that in susceptible people this type of temporary disruption to sleep can be the catalyst for the development of chronic insomnia. METHOD: Established sleep and depression rating instruments were used to monitor the sleep of 57 cardiac and 29 orthopaedic patients after elective surgery (n = 86), recruited through a hospital preadmission clinic. RESULTS: Preadmission chronic insomnia of 10% was consistent with general population prevalence estimates of 6-12%. Three months after discharge the incidence had almost doubled to 19%. Sixty-one per cent of this variance could be explained by hyperarousal, sleep hygiene issues, and dysfunctional cognitions about sleep. Depression was found to be a salient predictor but not an independent risk factor. Age, sex, and hospital-related data, such as score for difficulty sleeping in hospital, proved to be statistically insignificant. CONCLUSIONS: The results support the role of hyperarousal and dysfunctional sleep attitudes and behaviours as stronger predictors of chronic insomnia than patient demographics or environmental issues. Given that most of the patients were ambivalent about how they slept in hospital, with high satisfaction (71%) in the presence of significant disruption (63%), preadmission sleep education given to these patients prior to admission potentially contributed to the development of more realistic expectations of the quality of in-hospital sleep.

Adult↗

PubMed1993

Behavioral effects of cholinergic grafts.

Experimental work in animals and, to a more limited extent, in humans, has demonstrated that the cholinergic system is involved in mechanisms which control learning and memory. Since there is cholinergic loss in a variety of dementing illnesses, any treatment designed to alleviate the mental symptoms of these diseases must address the issue of cholinergic dysfunction even if other treatments are also required to overcome other neurotransmitter imbalances. Work in rodents has demonstrated that cholinergic-rich fetal neural tissue transplants can, under certain circumstances, alleviate the behavioral effects of cholinergic lesions or of cholinergic decline associated with aging. More complex cognitive testing can be achieved using primates and, in this case, the common marmoset is a suitable species to use because its rapid and reliable reproductive rate aids the provision of appropriate transplant tissue. Marmosets with transection of the fornix are deprived of a cholinergic input into the dentate gyrus, posterior hippocampus and entorhinal cortex and are specifically impaired on learning tasks which require remembering a rule of responding (non-evaluative memory). Transplantation of cholinergic-rich fetal septal tissue into the hippocampus of such animals completely restores their ability to learn this type of task, whereas transplantation of cholinergic-poor fetal hippocampal tissue into the same area produces no such improvements. These results demonstrate that where a learning impairment is produced by a relatively simple procedure which has a major effect on one neurotransmitter, that function can be restored by transplantation of tissue containing that neurotransmitter even where the impairment consists of a very "high level" cognitive dysfunction.

Acetylcholine↗

PubMed2000

Changes in the normal appearing brain tissue and cognitive impairment in multiple sclerosis.

OBJECTIVES: To assess (a) whether the changes in the normal appearing brain tissue (NABT), as revealed by magnetisation transfer (MT) histogram analysis, correlates with cognitive dysfunction in patients with multiple sclerosis and (b) the relative contribution of these changes by comparison with that of multiple sclerosis lesions visible on conventional MRI. METHODS: Dual echo, T1 weighted and MT scans of the brain were obtained in 12 patients with multiple sclerosis with cognitive impairment and in seven without cognitive impairment. Lesion loads were assessed from T2 and T1 weighted scans. To create MT histograms of the NABT, multiple sclerosis lesion outlines from dual echo scans were superimposed automatically and nulled out from the coregistered and scalp stripped MTR maps. Average lesion MT ratio (MTR) and brain size were also measured. RESULTS: T2 and T1 lesion loads were significantly higher and the average lesion MTR and brain size were significantly lower in the group of cognitively impaired patients. Patients with cognitive deficits also had significantly lower average MTR and peak location of the NABT histogram. Logistic regression analysis showed that 68% of the total variance was explained by average NABT-MTR alone. A multivariable regression model showed that NABT-MTR was the only factor that significantly correlated with cognitive impairment in these patients (p=0.001). CONCLUSIONS: The extent of abnormalities which go undetected when using conventional MRI is relevant in determining cognitive impairment in multiple sclerosis.

Adult↗

PubMedDate not supplied

Predictors of course and outcome in hypochondriasis after cognitive-behavioral treatment.

BACKGROUND: Predictors of treatment outcome were evaluated in a clinical sample suffering from hypochondriasis. METHODS: The sample consisted of 96 patients with hypochondriacal disorder according to DSM-IV or high syndrome scores on the Illness Attitude Scales (IAS) or Whiteley Index (WI). After intense inpatient cognitive-behavioral treatment (CBT), 60% of the patients were classified as responders because of substantial improvements or recovery from hypochondriacal symptomatology. RESULTS: Non-responders were characterized by a higher degree of pre-treatment hypochondriasis, more somatization symptoms and general psychopathology (SCL-90R), more dysfunctional cognitions related to bodily functioning, higher levels of psychosocial impairments, and more utilization of the health care system as indicated by the number of hospital days and costs for inpatient treatments and medication. No predictive value was found for sociodemographic variables, comorbidity with other mental disorders and chronicity. Multiple linear regression showed that pre-treatment variables significantly predicted IAS scores at post-treatment (R(2) = 0.59), changes during treatment (0.10), IAS scores at follow-up two years later (0.41) and changes between baseline and follow-up (0.25). CONCLUSIONS: The results demonstrate the relevance of various psychopathological variables and health care utilization as important indicators for outcome and further course of clinical hypochondriasis.

Adult↗

PubMed2001

SIB-1553A, (+/-)-4-[[2-(1-methyl-2-pyrrolidinyl)ethyl]thio]phenol hydrochloride, a subtype-selective ligand for nicotinic acetylcholine receptors with putative cognitive-enhancing properties: effects on working and reference memory performances in aged rodents and nonhuman primates.

Preclinical and clinical data have suggested the potential use of nicotinic acetylcholine receptor (nAChR) ligands for treating cognitive dysfunction associated with neurodegenerative diseases, such as Alzheimer's disease. SIB-1553A, (+/-)-4-[[2-(1-methyl-2-pyrrolidinyl)ethyl]thio]phenol hydrochloride, a novel nAChR ligand with predominant agonist subtype selectivity for beta4 subunit-containing human neuronal nAChRs, was tested in a variety of cognitive paradigms in aged rodents and nonhuman primates after acute and repeated administration. Subcutaneous administration of SIB-1553A improved delayed nonmatching to place performance in aged mice. In aged rhesus monkeys, intramuscular and oral administration of SIB-1553A improved choice accuracy in a delayed matching to sample task. SIB-1553A improved performances in these spatial and nonspatial working memory tasks but was less effective at improving performances in spatial reference memory tasks (i.e., aged rodents exposed to a discrimination task in a T-maze or trained to locate a hidden platform in a water maze). These data suggest that SIB-1553A has a predominant effect on attention/working memory processes. SIB-1553A also induced the release of acetylcholine in the hippocampus of aged rats and was equally effective whether administered acutely or repeatedly (6 weeks of daily subcutaneous administration). Thus, rats repeatedly treated with SIB-1553A exhibit neither tolerance nor sensitization to the effects of the compound. The SIB-1553A-induced cognitive improvement may be in part related to an increase in cholinergic function. The present study provides additional support for the use of subtype-selective nAChR ligands as a potential therapy for the symptomatic treatment of specific cognitive deficits (such as attention/working memory deficits) associated with aging and neurological diseases.

Aging↗

PubMed1999

Multivariate analysis of primitive reflexes in patients with human immunodeficiency virus type-1 infection and neurocognitive dysfunction.

To prove that primitive reflexes are independent markers of symptomatic human immunodeficiency virus type-1 (HIV-1) infection, a case-control study was carried out in a tertiary care, university teaching hospital. Thirty HIV-1-positive symptomatic cases, 30 seropositive asymptomatic controls and 30 HIV-1 seronegative controls consented to participate and were selected consecutively. A single examiner blinded to serostatus administered the Mini-Mental State Exam and a structured neurological exam to each participant. Up to 45% of cases had cognitive impairment. The occurrence of neurologic signs between seropositive cases and seropositive controls was similar, but the number of primitive reflexes was significantly higher in cases (P < 0.001). By multivariate discriminant analysis, all primitive reflexes but two correctly classified 83.3% of all participants (P = 0.0013). The model had a positive predictive value of 97% when motor, mood, and cognitive symptoms were added (P = 0.0001). Primitive reflexes were independent predictors of HIV-1 serostatus, especially for those with cognitive dysfunction. Primitive reflexes should be included in future case definitions of HIV-1-related neurocognitive disorders.

AIDS Dementia Complex↗