Post-Mortem diagnosis of dementia by informant interview

The diagnosis of normal cognition or dementia in the Brazilian Brain Bank of the Aging Brain Study Group (BBBABSG) has relied on postmortem interview with an informant.

OBJECTIVES

To ascertain the sensitivity and specificity of postmortem diagnosis based on informant interview compared against the diagnosis established at a memory clinic.

METHODS

A prospective study was conducted at the BBBABSG and at the Reference Center for Cognitive Disorders (RCCD), a specialized memory clinic of the Hospital das Clínicas, University of São Paulo Medical School. Control subjects and cognitively impaired subjects were referred from the Hospital das Clínicas to the RCCD where subjects and their informants were assessed. The same informant was then interviewed at the BBBABSG. Specialists' panel consensus, in each group, determined the final diagnosis of the case, blind to other center's diagnosis. Data was compared for frequency of diagnostic equivalence. For this study, the diagnosis established at the RCCD was accepted as the gold standard. Sensitivity and specificity were computed.

RESULTS

Ninety individuals were included, 45 with dementia and 45 without dementia (26 cognitively normal and 19 cognitively impaired but non-demented). The informant interview at the BBBABSG had a sensitivity of 86.6% and specificity of 84.4% for the diagnosis of dementia, and a sensitivity of 65.3% and specificity of 93.7% for the diagnosis of normal cognition.

CONCLUSIONS

The informant interview used at the BBBABSG has a high specificity and sensitivity for the diagnosis of dementia as well as a high specificity for the diagnosis of normal cognition.

The dorsal raphe nucleus shows phospho-tau neurofibrillary changes before the transentorhinal region in Alzheimer's disease. A precocious onset?

AIMS

Alzheimer's disease (AD) is a progressive and irreversible disease. There is strong evidence that the progression of the phospho-tau neurofibrillary cytoskeletal changes, rather than the beta-amyloid burden, is crucial in determining the severity of the dementia in AD. The Braak and Braak staging system (BB) focuses mainly on the cortical cytoskeletal pathology and classifies this progressive pathology into six stages, spreading from the transentorhinal region to primary cortices. Although it is reported elsewhere that the midbrain's dorsal raphe nucleus (DR), which is connected with those areas of the cerebral cortex undergoing early changes during BB I and II, exhibits AD-related cytoskeletal pathology, this nucleus has not been considered by the BB.

METHODS

To determine during which BB stage and how frequently the DR is affected by AD-related neurofibrillary changes, we studied the DR of 118 well-characterized individuals of the Brain Bank of the Brazilian Aging Brain Study Group categorized according to the BB. Thirty-eight of these individuals were staged as BB = 0, and 80 as BB >or= 1.

RESULTS

In all of the BB >or= 1 individuals (cortical neurofibrillary changes were present at least in the transentorhinal region) and in more than 1/5 of the BB = 0 individuals neurofibrillary changes were detected in the supratrochlear subnucleus of the DR.

CONCLUSIONS

These observations: (i) support the hypothesis of transneuronal spread of neurofibrillary changes from the DR to its interconnected cortical brain areas; and (ii) indicate that the supratrochlear subnucleus of the DR is affected by neurofibrillary changes before the transentorhinal cortex during the disease process underlying AD.

Combined instruments for the screening of dementia in older people with low Education

OBJECTIVE: To determine which combination of cognitive tests and informant reports can improve the diagnostic accuracy of dementia screening in low educated older people. METHOD: Patients with mild to moderate dementia (n=34) according to ICD-10 and DSM-III-R criteria and 59 older controls were assessed with the Mini-Mental State Examination (MMSE) and the Fuld Object Memory Evaluation (FOME). Informants were assessed using the Informant Questionnaire on Cognitive Decline in the Elderly and the Bayer-Activities of Daily Living Scale. RESULTS: The 4 instruments combined with the mixed rule correctly classified 100% and the logistic regression (weighted sum) classified 95.7% of subjects. The weighted sum had a significantly larger ROC area compared to MMSE (p=0.008) and FOME (p=0.023). The specificity of the tested combinations was superior to the MMSE alone (p=0.002). CONCLUSIONS: Cognitive tests combined with informant reports can improve the screening of mild to moderate dementia in low educated older people.

Predictors of in-hospital mortality among older patients

OBJECTIVE

The objective of this study was to determine predictors of in-hospital mortality among older patients admitted to a geriatric care unit.

INTRODUCTION

The growing number of older individuals among hospitalized patients demands a thorough investigation of the factors that contribute to their mortality.

METHODS

This was a prospective observational study implemented from February 2004 to October 2007 in a tertiary university hospital. A consecutive sample of 922 patients was evaluated for possible inclusion in this study. Patients hospitalized for palliative care, those who declined to participate, and those with incomplete data were excluded, resulting in a group of 856 patients aged 60 to 104 years. Bivariate and multivariate analyses were performed to determine associations between in-patient mortality and gender, age, length of stay, number of prescribed medications and diagnoses at admission, history of heart failure, neoplastic disease, immobility syndrome, delirium, infectious disease, and laboratory tests at admission (serum albumin and creatinine).

RESULTS

The overall mortality rate was 16.4%. The following factors were associated with higher in-hospital mortality: delirium (OR=4.13, CI=2.65-6.44, P<.001), neoplastic disease (OR=3.38, CI=2.11-5.42, P<.001), serum albumin levels at admission < 3.3 mg/dL (OR=3.23, CI=2.03-5.13, P<.001), serum creatinine levels at admission > or = 1.3 mg/dL (OR=2.39, CI=1.53-3.72, P<.001), history of heart failure (OR=1.97, CI=1.20-3.22, P=.007), immobility (OR=1.84, CI=1.16-2.92, P =.009), and advanced age (OR=1.03, CI=1.01-1.06, P=.019).

CONCLUSIONS

This study strengthens the perception of delirium as a mortality predictor among older inpatients. Cancer, immobility, low albumin levels, elevated creatinine levels, history of heart failure and advanced age were also related to higher mortality rates in this population.

Progressive resistance training in elderly HIV-positive patients: does it work?

BACKGROUND

Elderly people present alterations in body composition and physical fitness, compromising their quality of life. Chronic diseases, including HIV/AIDS, worsen this situation. Resistance exercises are prescribed to improve fitness and promote healthier and independent aging. Recovery of strength and physical fitness is the goal of exercise in AIDS wasting syndrome.

OBJECTIVE

This study describes a case series of HIV-positive elderly patients who participated in a progressive resistance training program and evaluates their body composition, muscular strength, physical fitness and the evolution of CD4+ and CD8+ cell counts.

METHODS

Subjects were prospectively recruited for nine months. The training program consisted of three sets of 8-12 repetitions of leg press, seated row, lumbar extension and chest press, performed with free weight machines hts, twice/week for one year. Infectious disease physicians followed patients and reported all relevant clinical data. Body composition was assessed by anthropometric measures and dual-energy x-ray absorptiometry before and after the training program.

RESULTS

Fourteen patients, aged 62-71 years old, of both genders, without regular physical activity who had an average of nine years of HIV/AIDS history were enrolled. The strengths of major muscle groups increased (74%-122%, p=0.003-0.021) with a corresponding improvement in sit-standing and walking 2.4 m tests (p=0.003). There were no changes in clinical conditions and body composition measures, but triceps and thigh skinfolds were significantly reduced (p=0.037). In addition, there were significant increases in the CD4+ counts (N=151 cells; p=0.008) and the CD4+/CD8+ ratio (0.63 to 0.81, p=0.009).

CONCLUSION

Resistance training increased strength, improved physical fitness, reduced upper and lower limb skinfolds, and were associated with an improvement in the CD4+ and CD4+/CD8+ counts in HIV positive elderly patients without significant side effects.

Assessment of factors that confound MRI and neuropathological correlation of human postmortem brain tissue

In spite of considerable technical advance in MRI techniques, the optical resolution of these methods are still limited. Consequently, the delineation of cytoarchitectonic fields based on probabilistic maps and brain volume changes, as well as small-scale changes seen in MRI scans need to be verified by neuronanatomical/neuropathological diagnostic tools. To attend the current interdisciplinary needs of the scientific community, brain banks have to broaden their scope in order to provide high quality tissue suitable for neuroimaging- neuropathology/anatomy correlation studies. The Brain Bank of the Brazilian Aging Brain Research Group (BBBABSG) of the University of Sao Paulo Medical School (USPMS) collaborates with researchers interested in neuroimaging-neuropathological correlation studies providing brains submitted to postmortem MRI in-situ. In this paper we describe and discuss the parameters established by the BBBABSG to select and to handle brains for fine-scale neuroimaging-neuropathological correlation studies, and to exclude inappropriate/unsuitable autopsy brains. We tried to assess the impact of the postmortem time and storage of the corpse on the quality of the MRI scans and to establish fixation protocols that are the most appropriate to these correlation studies. After investigation of a total of 36 brains, postmortem interval and low body temperature proved to be the main factors determining the quality of routine MRI protocols. Perfusion fixation of the brains after autopsy by mannitol 20% followed by formalin 20% was the best method for preserving the original brain shape and volume, and for allowing further routine and immunohistochemical staining. Taken to together, these parameters offer a methodological progress in screening and processing of human postmortem tissue in order to guarantee high quality material for unbiased correlation studies and to avoid expenditures by post-imaging analyses and histological processing of brain tissue.

Clinicopathological correlates of Alzheimer's disease in a general autopsy series from Brazil

The current neuropathological staging models of Alzheimer’s disease (AD) have been developed within the last 20 years. Nevertheless, they were mostly tested on Caucasians of Northern European ancestry or on Asians.

Prevalence of hearing impairment in patients with mild cognitive impairment

The correlation between hearing and cognition is well established in dementia, but not in mild cognitive impairment (MCI).

OBJECTIVE

The aim of the present study was to define the prevalence of hearing impairment in elderly patients with MCI and in controls.

METHODS

Twenty-nine patients with MCI and 24 control subjects were analyzed. We evaluated memory and hearing impairments through clinical tests, including the Mini Mental Status Examination, Clinical Dementia Rating (CDR) and Hearing Handicap Inventory for the Elderly Screening (HHIE-S). Audiometries were performed in 22 patients with MCI and 19 subjects in a control group.

RESULTS

MCI patients showed more hearing complaints (68.9%) compared to the control group (25%) (p=0.001). No differences in the intensity of hearing complaints, measured by the HHIE-S, were detected. Nonetheless, differences between mean hearing threshold (MCI group=23.4±11.3dB and control group=16.0±10.1dB) (p=0.03) were identified.

CONCLUSIONS

There is a significant association between MCI and hearing impairment. Hearing impairment in MCI patients may be a contributory factor to cognitive decline. This may however be related to the same neuropathological process, due to lesions of cortical areas related to hearing. The early diagnosis of hearing impairment in MCI patients may offer a more appropriate approach to this disease.

Adverse drug reactions in an elderly hospitalised population: inappropriate prescription is a leading cause

OBJECTIVE

Adverse drug reactions (ADRs) represent a major public health problem in the aged. In order to better evaluate this problem in Brazil, this study was designed to assess the prevalence of ADRs in an elderly hospitalised population, identify the most common ADRs and the principal medications involved, evaluate the appropriateness of use of these drugs in elderly people and determine the risk factors implicated in the appearance of such ADRs.

METHODS

The study population was comprised of 186 elderly patients (> or =60 years of age) admitted to the internal medicine service of a teaching hospital. The patients were assessed by a single observer using an intensive drug surveillance method to identify and report ADRs. The degree of probability for each adverse reaction was determined using the Naranjo algorithm.

RESULTS

The mean (+/- SD) age of the patients studied was 73.6 +/- 9.1 years. Up to 115 patients (61.8%) of the study population presented at least one ADR. A total of 199 ADRs were found, at an average of 1.7 per patient. The ADRs appeared during hospitalisation in 46.2% of the study population, were present at the time of the admission but did not cause hospitalisation in 17.2% of patients, and were the cause of admission in 11.3% of patients. The most frequent ADR that caused hospitalisation was digitalis toxicity (22.7% of such ADRs). Hypokalaemia as a result of diuretics was the most prevalent ADR both during hospitalisation (11.8%) and at the time of admission without being the cause (12.1%). Captopril was the most frequently prescribed drug (138 prescriptions), and led to an ADR in 18.1% of patients who received the drug. Almost a quarter of the patients presenting an ADR were prescribed drugs considered inappropriate for the elderly. By means of a multiple logistic regression model, the following were considered to be significant risk factors for the appearance of ADRs: number of diagnoses (odds ratio [OR] 1.40; 95% CI 1.06, 1.86), number of drugs (OR 1.07; 95% CI 1.01, 1.13) and use of drug that is inappropriate for the elderly (OR 2.32; 95% CI 1.17, 4.59).

DISCUSSION

The main contribution of the present study was identification of use of drugs that are considered inappropriate for elderly populations as a major risk factor for presenting an ADR. This finding is useful for continuous education programmes, therapeutic committees and policy makers, because adverse effects complicate the course of diseases in aged patients, cause hospitalisation and/or require the prescription of additional drugs. In addition to contributing to a reduction in healthcare costs, continuous efforts to promote rational drug use could also benefit elderly patients by preventing some avoidable drug toxicity.

CONCLUSION

A significant prevalence of ADRs was found among hospitalised elderly people. The risk factors associated with ADRs in this population included use of drugs considered to be inappropriate for that population, number of previous diagnoses and number of administered drugs. More appropriate drug prescription could avoid part of this burden of disease by minimising preventable ADRs.

Effects of exercise training on papain-induced pulmonary emphysema in Wistar rats

The purpose of the present study was to evaluate the role of exercise training on the development of papain-induced emphysema in rats. Our hypothesis was that the increase in pulmonary tissue stretching associated with exercise could increase the severity of a protease-induced emphysema. Wistar rats were randomly assigned to four groups (n = 10 for each group) that received, respectively, intratracheal infusion of papain (6 mg in 1 ml of 0.9% NaCl) or vehicle and were submitted or not to a protocol of exercise on a treadmill. Rats exercised at 13.3 m/min, 6 days/wk, for 9 wk (increasing exercise time, from 10 to 35 min). We measured respiratory system elastance and resistance, the size and weight of the heart, and pulmonary mean linear intercept (Lm). After 9 wk of exercise training, there were no differences in respiratory system resistance and elastance values among the four experimental groups. Volume of the heart was significantly greater in rats submitted to exercise training (P = 0.007) compared with sedentary rats due to increases in volumes of both right and left cardiac chambers. Lm was significantly greater in rats that received papain compared with saline-infused rats (P = 0.025). Surprisingly, this was true, even though there was no significant decrease in elastance, possibly due to connective tissue remodeling. However, Lm was significantly greater in papain + exercise rats compared with rats that received papain and were not submitted to exercise. We conclude that exercise training can increase alveolar damage induced by papain infusion.