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M L Chaves

Publications and source records attributed to M L Chaves.

17 recordsLinked to original sources
PubMed2001

Association between mental health screening by self-report questionnaire and insomnia in medical students.

Epidemiological research points to the high prevalence of psychiatric disorders among insomniacs. We carried out a cross-sectional study with medical students with the aim of evaluating the association between insomnia and suspicion of psychiatric disorder; 302 medical students were included (184 males and 118 females; mean age = 20.47+/-1.89 years). The main association was tested by logistic regression analysis. The overall prevalence of positivity in a screening test for psychiatric disorder was 22.19%; and of insomnia, 28.15%. Difficulty initiating sleep (OR=3.45), difficulty maintaining sleep (OR=7.61), falling asleep later (OR=1.99) and waking up earlier (OR=1.91) were associated with suspicion of psychiatric disorder. As a group, the variables difficulty initiating sleep, difficulty maintaining sleep, falling asleep after 11 pm, and waking up before 6 am presented an odds ratio of 5.96 for positivity in the screening for psychiatric disorder. Furthermore, difficulty maintaining sleep (OR=2.24) was associated with "being female," and falling asleep later (OR=0.43) was associated with "being male". These results underscore the importance of determining in what cases difficulty sleeping may have severe clinical repercussions or affect performance.

Adult↗
PubMed1999

Diagnosing dementia and normal aging: clinical relevance of brain ratios and cognitive performance in a Brazilian sample.

The main objective of the present study was to evaluate the diagnostic value (clinical application) of brain measures and cognitive function. Alzheimer and multi-infarct patients (N = 30) and normal subjects over the age of 50 (N = 40) were submitted to a medical, neurological and cognitive investigation. The cognitive tests applied were Mini-Mental, word span, digit span, logical memory, spatial recognition span, Boston naming test, praxis, and calculation tests. The brain ratios calculated were the ventricle-brain, bifrontal, bicaudate, third ventricle, and suprasellar cistern measures. These data were obtained from a brain computer tomography scan, and the cutoff values from receiver operating characteristic curves. We analyzed the diagnostic parameters provided by these ratios and compared them to those obtained by cognitive evaluation. The sensitivity and specificity of cognitive tests were higher than brain measures, although dementia patients presented higher ratios, showing poorer cognitive performances than normal individuals. Normal controls over the age of 70 presented higher measures than younger groups, but similar cognitive performance. We found diffuse losses of tissue from the central nervous system related to distribution of cerebrospinal fluid in dementia patients. The likelihood of case identification by functional impairment was higher than when changes of the structure of the central nervous system were used. Cognitive evaluation still seems to be the best method to screen individuals from the community, especially for developing countries, where the cost of brain imaging precludes its use for screening and initial assessment of dementia.

Age Factors↗
PubMed1997

Mental health screening by self-report questionnaire among community adolescents in southern Brazil.

PURPOSE: To evaluate the frequency of symptoms of depression, suicidal ideation, suicide behavior, and hopelessness among adolescents in southern Brazil. METHODS: The Self-Report Questionnaire (SRQ) was administered to a random sample of 126 community youngsters to screen for mental problems, the Montgomery-Asberg Depression Rating scale for signs and symptoms of depression, an adapted version of DIS (Diagnostic Interview Schedule) for suicidal ideation and behavior, and the Back's Hopelessness scale (adapted version). Social class, cognitive performance, age, and sex were also analyzed. RESULTS: Levels of symptoms of depression, suicidal ideation and behavior, and hopelessness were higher among those who were SRQ positive (8%). Female youngsters presented higher SRQ scores and on the Montgomery-Asberg scale. Cognitive performance was similar among all groups. Differences were not found according to social classes. The 15-17 year-old individuals (middle stage) presented higher hopelessness than the other stages of adolescence. CONCLUSIONS: The present findings suggest that screening for mental health conditions by self-report questionnaires may be of value of identify groups at major risk for violent, self-destructive behavior among community adolescents.

Adolescent↗
PubMed1996

Mild depression levels alter self-perceptions of future but not the recall of verbal information in elderly inpatients.

In order to determine the correlation of levels of symptoms of depression and rate of forgetting and perception of the future, a total of 68 elderly inpatients without Major Depression admitted to a general hospital were evaluated by: 1) the Montgomery-Asberg Depression Rating Scale (MADRS), 2) the Mini-Mental State Examination (MMSE), 3) a questionnaire on future self-perceptions (FSPQ), and 4) a test on the recall of verbal information to estimate the rate of forgetting. They were grouped according to the clinical prognosis of their disease (good, N = 48, 25 women, 23 men, age mean +/- SD, 68 +/- 6.64; poor, N = 20, 10 women, 10 men, age mean +/- SD, 69 +/- 6.68) which correlates with morbidity-mortality rates (low/high). There was no relationship between mild levels of signs and symptoms of depression and increased forgetting. However, levels of depression were negatively correlated to the score of future perceptions (B = -0.18, beta = -0.29, P = 0.032). Patients with diseases with good prognosis did not present different levels of depression, rates of forgetting or future expectations from those of patients with poor prognosis (high mortality rates). However, individuals with negative FSPQ scores showed significantly higher MADRS scores, independent of the type of disease. These data suggest that the modifications in the processing of information related to the future are present in clinical patients without Major Depression but they occur within a small range of very mild signs and symptoms of depression.

Aged↗
PubMed1995

Memory dysfunction and autonomic neuropathy in non-insulin-dependent (type 2) diabetic patients.

Considering the nervous system as a unit, it might be expected that diabetic patients with autonomic neuropathy could have a central abnormality expressed as cognitive dysfunction. To determine whether autonomic neuropathy is independently associated with cognitive dysfunction, we studied a cross-section of 20 non-insulin-dependent diabetic patients with autonomic neuropathy (14 males and six females; age (mean) = 60 + or - 1 years); 29 non-insulin-dependent diabetic patients without autonomic neuropathy (14 males and 15 females; age = 59 + or - 1 years) and 34 non-diabetic patients (10 males and 24 females; age = 58 + or - 1 years), matched by age, education and duration of disease. Cognitive function was evaluated by tests of immediate, recent and remote memory: verbal (digit span; word span) and visual (recognition of towers and famous faces). Diabetic patients with autonomic neuropathy scored (median) lower in visual memory tests than diabetic patients without autonomic neuropathy and controls (towers immediate = 5 versus 7 and 6; towers recent = 4 versus 6 and 6; faces = 16 versus 18 and 18; respectively; Kruskal-Wallis; P < 0.05). There was no difference in verbal memory performance (Kruskal-Wallis; P > 0.05). Entering age, education, duration of disease and fasting plasma glucose in a stepwise multiple regression, the performance in these tests remained associated with autonomic neuropathy (towers immediate, P = 0.0054, partial r2 = 0.166; towers recent, P = 0.0076, partial r2 = 0.163). Scores in visual tests correlated negatively with the number of abnormal cardiovascular tests (faces, r = -0.25; towers recent, r = -0.24; Spearman; P < 0.05). Decreased visual cognitive function in non-insulin-dependent diabetic patients is associated with the presence and degree of autonomic neuropathy.

Adult↗
PubMed1993

Chronic use of benzodiazepines and cognitive deficit complaints: a risk factor study.

Benzodiazepines produce an anterograde amnesia after acute administration but whether their chronic use is hazardous to memory processes remains unclear. The present study analyses the risk of increasing cognitive complaints with chronic benzodiazepine use. Subjects seeking medical assistance at the General Internal Medicine Outpatient Clinic of Hospital de Clinicas de Porto Alegre, were interviewed before seeing physicians. They were asked about use of benzodiazepines, history of neurological and psychiatric diseases, use of alcohol, and deficits in remembering and learning as well as age, sex and level of education. Age (over 51 years), low level of education, a history of neurological and psychiatric diseases and use of benzodiazepines showed significant associations with cognitive complaints. After a conditional logistic regression analysis, benzodiazepine use lost its association with memory complaints. These data support the hypothesis that the chronic use of benzodiazepines does not carry a risk for cognitive deficits complaints.

Adult↗
PubMed1992

Differential diagnosis between dementia and depression: a study of efficiency increment.

A battery of neuropsychological tests was examined to establish its value in differentiating mild dementia from depression. The battery was applied to 84 subjects: 31 dementia patients of several etiologies, 31 patients with major depression and 22 volunteers whose age and educational level was similar to that of the patients. The battery consisted of tests for immediate, recent and remote memory, the Mini Mental State examination, a screening test for language disorders, and tests measuring abstraction, calculation, judgement, praxic and gnosic functions. The results showed significant differences among the three groups in all memory tests. Deficits of abstraction, calculation, praxis and language functions were strongly associated with dementia. The epidemiological analysis of efficiency increment, with determination of sensitivity and specificity, showed a highly significant enhancement of efficiency for diagnostic purposes when the results of the tests were combined. These findings suggest that the entire battery of neuropsychological tests should be applied, and their results compared using the efficiency increment procedure, in order to establish a firm differential diagnosis between dementia and depression, and/or to detect the former when it is at a mild early stage.

Adult↗
PubMed1992

[Cognitive changes in workers at a data processing company].

A study of 191 data processing workers undertaken in Porto Alegre, Brazil, in 1989, is presented. The relationship between complaints of loss of memory and their respective scores on cognitive testing in three groups of workers, one with automatized repetitive activities and two others with diversified activities, is analysed. The scores and complaints are compared with the results of a screening test for psychiatric disorders in order to verify the influence of this confounding factor. No significant evidence of cognitive problems was found despite the high prevalence of complaints of memory loss in this population (65.4%). There is a significant statistical association between these complaints and the scores of the psychiatric testing. It is suggested that futures studies should emphasize psychiatric analysis with a view to clarifying the complaints of Data Processing workers.

Adult↗
PubMed1990

Diazepam inhibits retroactive interference of memory in humans: pretreatment with naltrexone does not alter this effect.

1. In a double-blind study of the effects of diazepam and naltrexone on retroactive memory interference, 88 healthy human volunteers were asked to study a text on the 1954 World Soccer Cup and were submitted to a written questionnaire on the material 48 h later. Three hours after reading the text, 58 of the subjects were exposed to a non-factual, derogatory comment on the World Cup. 2. All subjects were given either placebo or naltrexone (50 mg) before reading the text, and either placebo or diazepam (5 mg), per os, 2 h after reading the text (1 h prior to the comment). Subjects were assigned to the different treatment groups by a double-blind design. 3. Exposure to the derogatory comment caused retroactive memory interference with the retention of material from the text. Diazepam blocked the retroactive interference and had no effect of its own on retention of the text. Pretreatment with naltrexone did not influence retention, retrograde interference, or the effect of diazepam on these variables. 4. The results obtained here extend to healthy adult humans observations made on rats and mice in which diazepam blocked retroactive memory interference.

Adolescent↗
PubMed1990

The use of a new non-verbal test in the evaluation of recent memory.

A test for recent memory was developed using non-verbal material. The present report describes a series of experiments conducted to evaluate its reproducibility and the influences of changes in the interval between acquisition and retrieval, and age and level of instruction, and its sensitivity to the integrity of memory function. A total of 114 subjects participated in 5 experiments. The test of recent memory is reproducible over a period of at least 5 months and can be used with training-testing intervals of 24 to 48 h. The performance of the test is affected by age and level of instruction. Moreover, the memory test is sensitive to differences in the integrity of memory function. Thus, the memory test developed in this study may be used to evaluate the effects of behavioral and/or pharmacological manipulations on recent memory in homogeneous groups of subjects.

Adolescent↗
PubMed1988

The effect of non-factual post-training negative comment on the recall of verbal information.

Healthy human volunteers were asked to study a 250-word account of the 1954 World Football Cup and submitted to a questionnaire on the verbally learned material 48 h later. The subjects were divided into 7 groups. One received no treatment between text and questionnaire. The others were shown either a brief laudatory or derogatory comment on the World Cup 0, 3, or 6 h after having read the text. The comment contained no facts relevant to the text. Subjects exposed to the derogatory comment 0 or 3 h after having studied the text performed much worse in the questionnaire than any of the other groups. Performance in another, unrelated, general knowledge memory test was not affected by reading the World Cup text or subsequent comments. Thus post-event non-factual information was able to affect recall of verbally acquired factual material even if presented 3 h later; the effect does not seem to be explicable by a general performance deficit, and may be due to integration of information acquired during and after the event into one single experience.

Adult↗
PubMed1988

Naltrexone blocks the enhancing effect of novel experiences on performance in memory tests in humans.

Two experiments were carried out in healthy human volunteers in order to investigate the effect of novel experiences on retrieval, and the influence of naltrexone thereupon. Naltrexone (50 mg) and placebo (50 mg of starch) were given orally using a double blind design. In Experiment 1, the subjects were asked, on two consecutive days, to recall well-known facts or events, and to recall the year in which major events took place. On Day 2, some subjects were, and others were not, exposed to a nonsense text prior to testing, which was viewed as a novel experience by the subjects. Exposure to the text was followed by enhanced scores in both memory tests. The effect was blocked by naltrexone, but not by the placebo, given 1 hr prior to the novel experience; the treatments had no effect of their own in subjects unexposed to the nonsense text. In Experiment 2, the memory tests were the recognition of famous faces, and the dates test (see above); and the novel experience was being taken for 5 min to a room where they had never been before. Again, the novel experience was followed by increased scores in both memory tests in the untreated and placebo groups, but not in the naltrexone treated subjects. These results confirm previous findings on memory enhancement by pre-test exposure to novel experiences, and suggest that endogenous opioid, or at least naltrexone-sensitive, mechanisms are involved in the effect.

Adolescent↗
PubMed1988

Construction and reconstruction of memories.

1. Recent evidence suggests that treatments given after training may influence memory in two ways: by becoming themselves incorporated to the experience, or by altering post-training mechanisms involved in the storage of the experience. The two processes may be called consolidation. 2. Some endogenous substances that are normally released during or after training (brain beta-endorphin; the peripheral stress hormones, ACTH, epinephrine and vasopressin) appear to be of particular importance. Their effect may become incorporated to the experiences as a conditioned stimulus (CS), generating state dependency. The effect of beta-endorphin appears to be physiological, since the substance is released by novel experiences. 3. Post-event information provided by other training experiences, in rats, or by comments or leading words, in humans, may also incorporate to the experiences, altering their content qualitatively or quantitatively. 4. A variety of substances including the stress hormones at low doses and analeptic drugs may facilitate retention when given after training. In this case, the effect is best explained by an enhancement of the post-training strengthening of memory traces. 5. The reiteration of part of the experiences at the time of testing facilitates retrieval. This may be viewed as a reconstruction of consolidation at the time of retrieval, and may be obtained using cognitive material ("priming"), or neurohumoral stimuli (a beta-endorphin injection, or a presumable release of brain beta-endorphin by an interpolated novel experience). The effect can be seen in animals rendered amnestic by electroconvulsive shock, and in humans with amnesia of organic and non-organic nature. 6. The human amnesic syndrome seems, thus, largely explainable by a deficit of retrieval. It is possible that the stimulation of retrieval by priming, or by drugs, through the "reconstruction" of consolidation, may be useful for the relief or treatment of the human amnesic syndrome.

Amnesia, Retrograde↗
PubMed1986

Previous exposure to a novel experience enhances performance in two simple memory tests in humans.

Young healthy human volunteers (N = 52), non-amnesic patients (N = 53), and amnesic patients (N = 52) were submitted once a day on three consecutive days to two simple memory tests: recognition of the pictures of famous faces (actors, politicians, sports figures) cut from newspapers or news magazines, and the recall of the year in which widely publicized major events happened (the Pope's visit to Brazil, a famous fire that destroyed a block downtown, etc.). One, 3 or 6 h prior to testing either on the 2nd or the 3rd day, the subjects were exposed to one of the following experiences: staying in a room where they had never been before for 10 min, or a 5 min digit learning task to which they also had never been submitted. Exposure to either of the two novel experiences 1 or 3, but not 6, h before testing was followed by increased scores in both memory tests.

Adolescent↗
PubMed1971

[Abdominal tumor].

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Bile Duct Neoplasms↗