An investigation of clinical correlates of Lewy bodies in autopsy-proven Alzheimer disease

BACKGROUND

Studies of patients meeting clinical and pathologic criteria for Alzheimer disease (AD) have not consistently found associations between the presence of Lewy bodies (LBs) at postmortem examination and a higher frequency during life of the clinical features of dementia with LBs.

OBJECTIVE

To evaluate the clinical correlates of LBs in patients with AD.

DESIGN AND METHODS

Fifty-one patients were diagnosed as having probable AD during life and met pathologic criteria for AD. Semiquantitative ratings for LBs were obtained in 4 brain regions: substantia nigra, cingulate, insular cortex, and hippocampus. The patients had been followed up semiannually for up to 9.9 years before death, and clinical features associated with dementia with LBs, including extrapyramidal signs and visual hallucinations, were assessed at each study visit. Logistic regression analyses determined whether patients who had LBs were more likely than those without LBs to express specific clinical signs during follow-up. Cox analyses determined whether patients with LBs developed clinical signs or died earlier. Generalized estimating equations were used to compare rates of cognitive or functional change.

RESULTS

Nineteen of the 51 patients had at least 1 LB in one of the studied regions. In no case was a significant relation noted between LBs and the presence of a measured clinical sign. No LB measure was associated with an increased risk of developing any of the evaluated clinical signs earlier in the disease. There was no association between the presence of LBs and more rapid mortality or more rapid disease progression.

CONCLUSIONS

In patients diagnosed as having AD during life, we did not observe a relation of LBs noted during postmortem examination with the presence of any clinical feature that we assessed or with the rapidity of disease progression. The relation between LBs and specific clinical manifestations may be tenuous in these patients.

Clinical trials in HIV-associated cognitive impairment: cognitive and functional outcomes

Cognitive and functional outcomes are of primary interest in the design of efficacy trials in HIV-associated cognitive impairment. In a longitudinal cohort study, weak associations were found between measures of cognitive performance and commonly used measures of daily functioning (mostly self-report measures) in HIV-infected individuals. Modifications of current functional scales or new functional instruments are needed to assess the clinical relevance of cognitive changes in clinical trials of HIV-associated cognitive impairment.

Incidence of AD in African-Americans, Caribbean Hispanics, and Caucasians in northern Manhattan

OBJECTIVE

To compare the incidence rates for AD among elderly African-American, Caribbean Hispanic, and white individuals and to determine whether coincident cerebrovascular disease contributes to the inconsistency in reported differences among ethnic groups.

METHODS

This was a population-based, longitudinal study over a 7-year period in the Washington Heights and Inwood communities of New York City. Annual incidence rates for AD were calculated and compared by ethnic group, and cumulative incidence adjusted for differences in education, diabetes, cardiovascular risk factors, and stroke was calculated.

RESULTS

The age-specific incidence rate for probable and possible AD was 1.3% (95% CI, 0.8 to 1.7) per person-year between the ages of 65 and 74 years, 4.0% (95% CI, 3.2 to 4.8) per person-year between ages 75 and 84 years, and 7.9% (95% CI, 5.5 to 10.5) per person-year for ages 85 and older. Compared to white individuals, the cumulative incidence of AD to age 90 years was increased twofold among African-American and Caribbean Hispanic individuals. Adjustment for differences in number of years of education, illiteracy, or a history of stroke, hypertension, heart disease, or diabetes did not change the disproportionate risks among the three ethnic groups.

CONCLUSION

The incidence rate for AD was significantly higher among African-American and Caribbean Hispanic elderly individuals compared white individuals. The presence of clinically apparent cardiovascular or cerebrovascular disease did not contribute to the increased risk of disease. Because the proportion of African-American and Caribbean Hispanic individuals reaching ages 65 and older in the United States is increasing more rapidly than the proportion of white individuals, it is imperative that this disparity in health among the elderly be understood.

Cognitive correlates of mnemonics usage and verbal recall memory in old age

OBJECTIVES

The objectives of this study were to determine whether minimizing requisite processing resources to learn a word list would differentially improve recall of older adults and to examine the associations between memory and nonmemory cognitive abilities.

BACKGROUND

It has been hypothesized that a reduction in general processing resources contributes to age-related declines in memory and other cognitive abilities.

METHODS

Twenty-four young adults and 47 older adults were administered two semantically related word lists, one list with words blocked into their categories and the other with categories intermixed. Tests of attention and working memory, language, and abstract reasoning were interspersed with the memory tasks. Participants were classified as young (age range: 17-30 years), young-old (age range: 65-73 years), and old-old (age range: 74-87 years) to compare the effects of list condition (i.e., blocked vs. unblocked) on recall performance. Correlation and regression analyses were used to examine the cognitive correlates of recall performance.

RESULTS

Expected age differences in recall performance were observed. Based on the resource-reduction hypothesis of cognitive aging, we hypothesized that the blocked presentation of the to-be-remembered list would minimize processing demands and therefore differentially benefit recall in older elderly participants. Contrary to our prediction, however, the relative benefits of blocked list presentation on recall measures were comparable for young and older participants. Correlations and regression analyses revealed that recall performance was more strongly associated with word finding ability than with working memory or abstract reasoning skills.

CONCLUSIONS

Results suggest that level of recall of a semantically related word list and use of semantic clustering as an encoding strategy are associated more strongly with general word finding skills than with processing capacity.

Selective deficits in verbal working memory associated with a known genetic etiology: the neuropsychological profile of duchenne muscular dystrophy

Forty-one boys diagnosed with Duchenne muscular dystrophy (DMD) were each compared to an unaffected sibling on a battery of neuropsychological tests. Verbal. visuospatial, attention/memory, abstract thinking, and academic achievement skills were tested. Results indicated the boys with DMD performed similarly to their siblings on the majority of measures, indicating intact verbal, visuospatial, long-term memory, and abstract skills. However, the DMD group did significantly more poorly than their siblings on specific measures of story recall, digit span, and auditory comprehension, as well as in all areas of academic achievement (reading, writing, and math). This profile indicates that verbal working memory skills are selectively impaired in DMD, and that that likely contributes to limited academic achievement. The association between the known impact of the genetic mutation on the development of the central nervous system and boys' cognitive profile is discussed.

Primary neurilemoma of the thyroid gland: a case report

Primary nonepithelial tumors of the thyroid gland are rare. We present the case of a neurilemoma of the right lobe of the thyroid gland in a 20-year-old female patient. The tumor was asymptomatic and measured 2.5 x 1.2 cm in size. Histologic examination was consistent with an Antoni A-type neurilemoma. The tumor was excised without difficulty. Only 12 other cases of neurilemomas of the thyroid gland have been reported in the literature. We discuss the clinical, radiologic, and pathologic findings of this rare tumor.

Imaging physiologic dysfunction of individual hippocampal subregions in humans and genetically modified mice

We have developed a variant of functional magnetic resonance imaging (fMRI) designed to be sensitive to static neuronal function. This method is based on resting instead of dynamic changes in oxygen-dependent signal and therefore allows for a spatial resolution that can detect signal from different hippocampal subregions in human subjects as well as in mice. We found that hippocampal signal was significantly diminished in elderly subjects with memory decline compared to age-matched controls, and different subjects showed dysfunction in different subregions. Among healthy elders, signal intensity from the subiculum was correlated selectively with memory performance. This method does not require an activation task; it can be used in anesthetized normal and in genetically modified and cognitively impaired mice. In mice the signal was found to be sufficiently sensitive to detect functional changes in the absence of underlying anatomical changes.

Different brain networks mediate task performance in normal aging and AD: defining compensation

OBJECTIVE

To determine whether the pathologic mechanisms of AD alter the brain networks subserving performance of a verbal recognition task.

BACKGROUND

Functional imaging studies comparing task-related activation in AD patients and controls generally have not used network analysis and have not controlled for task difficulty.

METHODS

H2 15O PET was used to measure regional cerebral blood flow in 14 patients and 11 healthy elders during the performance of a serial verbal recognition task under two conditions: low demand, with study list size (SLS) equal to one; and titrated demand, with SLS adjusted so that each subject recognized words at 75% accuracy. The Scaled Subprofile Model was used to identify networks of regionally covarying activity across these task conditions.

RESULTS

In the elders, higher SLS was associated with the recruitment of a network of brain areas involving left anterior cingulate and anterior insula (R2 = 0.94; p < 0.0001). Three patients also expressed this network. In the remaining patients, higher SLS was associated with the recruitment of an alternate network consisting of left posterior temporal cortex, calcarine cortex, posterior cingulate, and the vermis (R2 = 0.81, p < 0.001). Expression of this network was unrelated to SLS in the elders and more intact AD patients.

CONCLUSIONS

The patients' use of the alternate network may indicate compensation for processing deficits. The transition from the normal to the alternate network may indicate a point where brain disease has irreversibly altered brain function and thus may have important implications for therapeutic intervention.

The role of routine laboratory studies and neuroimaging in the diagnosis of dementia: a clinicopathological study

OBJECTIVE

To determine the neuropathological diagnoses of longitudinally followed patients with potentially reversible causes of dementia and to examine the results of the "dementia work-up," especially neuroimaging, by comparison with the pathological diagnosis.

DESIGN

A neuropathologic series of 61 consecutive patients, with review of clinical, laboratory, neuroimaging, and pathological results.

RESULTS

Of the 61 patients, forty-eight (79%) had a clinical diagnosis of probable or possible Alzheimer's disease (AD). Compared with the pathological diagnosis, the sensitivity and specificity of the clinical diagnosis of AD were 96% and 79%, respectively. Of the 61 patients, 9 had abnormal laboratory tests, the correction of which did not improve the subsequent course. These patients were found to have AD8 and frontotemporal dementia on pathology. In two patients, neuroimaging was helpful in the clinical diagnoses of frontotemporal dementia and progressive supranuclear palsy (PSP). Neuroimaging revealed cerebrovascular disease in 18 patients, only two of whom were suspected clinically. Pathology confirmed AD in 17 and PSP in 1 of these patients. Sensitivity and specificity for the clinical diagnosis of cerebrovascular disease in comparison with pathology were 6% and 98%, respectively. With the added information from neuroimaging, that sensitivity increased to 59% and specificity decreased to 81%.

CONCLUSIONS

All cases with abnormal laboratory or neuroimaging results had AD or some other neurodegenerative disease on pathology. The "dementia work-up" did not reveal any reversible causes for dementia in this group of patients. Neuroimaging may have a role, especially in the diagnosis of possible AD with concomitant cerebrovascular disease.

Severe pain confounds neuropsychological test performance

There is little information on the effect of pain on neuropsychological test performance. We have undertaken this study to explore which tests are affected by pain, the magnitude of these changes, and other confounders of neuropsychological performance in a population of patients having spine surgery. Twenty-four elderly English speaking Caucasian patients (age > 60 years) were enrolled pre-operatively in this Institutional Review Board approved study. Pain scores using an 11-point Numeric Pain Intensity scale and performance on a neuropsychological battery (Controlled Oral Word Association, Rey Complex Figure, Trails A and B) were assessed at two times, before and one day after surgery. Scores were calculated using the standard algorithms and change scores were calculated by subtracting the baseline from follow-up scores. After surgery, performance on the Rey Complex Figure ( r = -0.577, p = 0.004) and Trails Part A (r = 0.527, p = 0.01) declined with increasing post-operative pain scores. Women reported higher pain scores post-operatively than men (p = 0.046), and performed worse than men for change in performance on Trails Part A (p = 0.027). These data suggest that pain can influence performance on certain cognitive tests, and that some gender differences in these effects may occur. Interpretation of performance measures should take into account possible effects of pain, although our understanding of pain effects and ability to predict them in individual people, currently are quite limited.

Evaluating the function of hippocampal subregions with high-resolution MRI in Alzheimer's disease and aging

Memory ability declines in older age groups. There is a growing list of physiological processes that target the hippocampal formation in an age-related fashion, and some might underlie the hippocampal component of memory decline. The hippocampal formation is comprised of separate subregions, and physiological processes differentially target these subregions. The ability to evaluate the functional integrity of individual subregions-performing subregional analysis-is a major clinical goal since it can aid in the diagnosis of memory decline, as well as in elucidating mechanisms of disease and testing potential interventions. Because of its superior spatial resolution, magnetic resonance imaging (MRI) is best suited to accomplish this goal. Despite limited success, most functional MRI (fMRI) protocols have difficulty in performing complete subregional analysis of the hippocampal formation. Here we address sources of difficulty by (1) generating T2* -weighted maps of the hippocampal formation with sub-millimeter resolution; and (2) by adapting an approach used by animal investigators to identify the hippocampal subregions using anatomical landmarks. The protocol is tested in patients with Alzheimer's disease and in healthy controls, in an effort to determine whether it can detect neuronal dysfunction. Results showed diminished signal in the hippocampal formation of patients with Alzheimer's disease (AD) compared to controls, and multivariate analysis showed that this difference was most prominent in the entorhinal cortex. The protocol can be used to perform subregional analysis of the hippocampal formation. Testing the protocol in other clinical populations is needed to demonstrate its efficacy in evaluating the neuronal integrity of all hippocampal subregions.

Olfactory deficits in patients with mild cognitive impairment predict Alzheimer's disease at follow-up

OBJECTIVE

This study evaluated the predictive utility of olfactory identification deficits in patients with mild cognitive impairment for follow-up diagnosis of probable Alzheimer's disease.

METHOD

Ninety outpatients with mild cognitive impairment were examined at 6-month intervals. Matched healthy comparison subjects (N=45) were examined annually. The University of Pennsylvania Smell Identification Test was given at baseline.

RESULTS

Olfaction scores were lower in patients with mild cognitive impairment than in healthy comparison subjects. Seventy-seven patients were followed up; 19 were diagnosed with Alzheimer's disease by 2 years. Patients with low olfaction scores (< or =34 of 40), and patients with low olfaction scores who reported no subjective problems smelling, were more likely to develop Alzheimer's disease than other patients. In a Cox proportional hazards model adjusted for age, sex, modified Mini-Mental State score, and education, low olfaction scores did not predict time until development of Alzheimer's disease, but low olfaction scores accompanied by lack of awareness of olfactory deficits predicted time to development of Alzheimer's disease. This effect remained when attention or memory measures replaced modified Mini-Mental State score in the model. In patients with high Mini-Mental State scores (> or =27 of 30), low olfaction with lack of awareness remained a significant predictor of Alzheimer's disease. Olfaction scores of 30-35 showed moderate to strong sensitivity and specificity for diagnosis of Alzheimer's disease at follow-up.

CONCLUSIONS

In patients with mild cognitive impairment, olfactory identification deficits, particularly with lack of awareness of olfactory deficits, may have clinical utility as an early diagnostic marker for Alzheimer's disease.

Motor impairment in PD: relationship to incident dementia and age

OBJECTIVE

To analyze the relationship of specific motor impairment in idiopathic PD to incident dementia.

BACKGROUND

The total Unified PD Rating Scale (UPDRS) motor score at baseline has been associated with an increased risk of developing dementia in PD.

METHODS

A cohort of 214 nondemented community-dwelling patients with PD was followed annually with neurologic and neuropsychological evaluations. The association of baseline motor impairment with incident dementia was analyzed using Cox proportional hazards models. Facial expression, tremor, rigidity, and bradykinesia were analyzed as part of subscore A (indicative of dopaminergic deficiency); speech and axial impairment were analyzed as part of subscore B (indicative of predominantly nondopaminergic deficiency). The correlation between the six motor domains and age was also analyzed.

RESULTS

Of 173 patients followed for at least 1 year, 50 became demented according to the Diagnostic and Statistical Manual of Mental Disorders, revised 3rd edition (DSM III-R) criteria (mean follow-up, 3.6 +/- 2. 2 years). When both subscores A and B were entered into the Cox model, subscore B was associated with incident dementia (relative risk = 1.19; 95% CI, 1.09 to 1.30; p = 0.0001), in addition to gender, age, and education, whereas subscore A was not (relative risk = 1.03; 95% CI, 0.99 to 1.07; p = 0.19). Of the six motor domains, speech and bradykinesia were associated with incident dementia (p < 0.05), and axial impairment approached significance (p = 0.06). Only axial impairment was correlated with age (correlation coefficient = 0.32; p < 0.001).

CONCLUSION

The findings suggest that motor impairment mediated predominantly by nondopaminergic systems is associated with incident dementia in PD. Axial impairment may be the result of a combined effect of the disease and the aging process.

Source memory and encoding strategy in normal aging

Of the memory deficits associated with aging, elders are most impaired at attributing the source to remembered information. Additionally, aging is marked by a decrease in the use of encoding strategies that are thought to enhance the acquisition and retention of information. We examined how manipulating the encoding strategy during acquisition affected item and source memory in 32 young and 68 elderly participants. Elderly participants were dichotomized into young-old and old-old based upon the median age (74 years). Memory was assessed using Word List A from the California Verbal Learning Test (CVLT) and its alternate form. Encoding strategy was manipulated by semantic clustering. For the Blocked List, words were presented grouped into their semantic categories, whereas for the Unblocked List categories were intermixed within the list. Item and source memory judgments were made 20 minutes after the final CVLT recall trial and again one week later. Results revealed a disproportionate decline in source, compared to item memory in the two older groups. Semantic blocking enhanced item memory for the elders, but not for the young. The amount of semantic clustering performed by the elders showed a decline with age and was positively related to source performance. Results also suggest that subtle age-related changes in semantic knowledge may be related to declines in semantic clustering and memory performance.

Validity of family history for the diagnosis of dementia among siblings of patients with late-onset Alzheimer's disease

We examined 180 siblings of 127 probands with probable or possible Alzheimer's dementia (AD) in a family study of AD. The overall sensitivity of a simple family history questionnaire was 64% and the specificity was 84%. Sensitivity improved 90-100% with minimal decline in specificity when we considered clinic-based vs. population survey patients. Higher education among informants and the availability of a spouse or a sibling as informant significantly increased sensitivity. Awareness of such factors may improve the yield of the family history in AD using a simple questionnaire.

Poor verbal working memory across intellectual level in boys with Duchenne dystrophy

OBJECTIVE

To determine whether all boys with Duchenne muscular dystrophy (DMD) have a similar verbal and memory profile of skills, or whether only a subset is affected, and to determine whether the weak areas in their profile are substantially different from a control group.

METHODS

Performance of patients with DMD on neuropsychological tests of verbal and memory skills was examined in two ways. Standardized test scores for 80 boys with DMD (estimated IQ range, 70 to 160) were ranked individually from worst to best, and the individual rankings were compared across the group using Friedman rank analysis. Additionally, performance of 41 boys with DMD was compared with that of their sibling control subjects of similar age and estimated IQ using multivariate analysis of variance.

RESULTS

Individual cognitive profiles were significantly similar among the subjects with DMD, such that for most subjects digit span, story recall, and comprehension were the tests on which each performed most poorly. This finding remained true regardless of whether they were of high or low intellectual function. In contrast, no significant cognitive profile was found among their sibling control subjects, and when compared with their siblings, the DMD group scored significantly more poorly on digit span, comprehension, and story recall, but not on other verbal and memory measures.

CONCLUSIONS

Boys with DMD have a specific cognitive profile, regardless of their general level of cognitive function. Specifically, boys with DMD performed more poorly on tests requiring attention to complex verbal information than they did on other verbal or memory measures. The possibility that the missing dystrophin brain products may contribute to selective cognitive processing is considered.

Frequency and clinical determinants of dementia after ischemic stroke

OBJECTIVE

To investigate the frequency and clinical determinants of dementia after ischemic stroke.

METHODS

The authors administered neurologic, neuropsychological, and functional assessments to 453 patients (age 72.0 +/- 8.3 years) 3 months after ischemic stroke. They diagnosed dementia using modified Diagnostic and Statistical Manual of Mental Disorders, 3rd ed., revised criteria requiring deficits in memory and two or more additional cognitive domains as well as functional impairment.

RESULTS

The authors diagnosed dementia in 119 of the 453 patients (26.3%). Regarding dementia subtypes, 68 of the 119 patients (57.1%) were diagnosed with vascular dementia, 46 patients (38.7%) were diagnosed with AD with concomitant stroke, and 5 patients (4.2%) had dementia for other reasons. Logistic regression suggested that dementia was associated with a major hemispheral stroke syndrome (OR 3.0), left hemisphere (OR 2.1) and right hemisphere (OR 1.8) infarct locations versus brainstem/cerebellar locations, infarcts in the pooled anterior and posterior cerebral artery territories versus infarcts in other vascular territories (OR 1.7), diabetes mellitus (OR 1.8), prior stroke (OR 1.7), age 80 years or older (OR 12.7) and 70 to 79 years (OR 3.9) versus 60 to 69 years, 8 or fewer years of education (OR 4.1) and 9 to 12 years of education (OR 3.0) versus 13 or more years of education, black race (OR 2.6) and Hispanic ethnicity (OR 3.1) versus white race, and northern Manhattan residence (OR 1.6).

CONCLUSIONS

Dementia is frequent after ischemic stroke, occurring in one-fourth of the elderly patients in the authors' cohort. The clinical determinants of dementia include the location and severity of the presenting stroke, vascular risk factors such as diabetes mellitus and prior stroke, and host characteristics such as older age, fewer years of education, and nonwhite race/ethnicity. The results also suggest that concomitant AD plays an etiologic role in approximately one-third of cases of dementia after stroke.

Potential role of growth factors and extracellular matrix in wound healing after laryngotracheal reconstruction

Laryngotracheal reconstruction (LTR) has been used for more than 20 years to treat infants and children with subglottic stenosis. Results after pediatric LTR have been satisfactory; however, approximately 10% of children have recurrent airway narrowing after LTR. The purpose of our study was to determine whether a correlation existed between specific growth factors and extracellular matrix in patients with adequate wound healing capability as compared with patients with poor wound healing capability. Histologic sections from 27 patients who underwent LTR were cut, and immunohistochemical staining was performed for transforming growth factor-beta, platelet-derived growth factor, fibronectin, tenascin, transforming growth factor-alpha, and vascular endothelial growth factor. Results showed that patients with adequate wound healing capability had a positive correlation with vasculature fibronectin, vasculature tenascin, and stromal fibronectin. Patients with poor wound healing capability had a positive correlation with stromal vascular endothelial growth factor.

Expression of Ki-67, tumor suppressor proteins, growth factor, and growth factor receptor in juvenile respiratory papillomatosis: Ki-67 and p53 as predictors of aggressive disease

The enhanced proliferation of epithelial cells is a typical feature of respiratory papilloma. The mechanism or mechanisms leading to abnormal epithelial proliferation remain unclear. Overexpression of growth factors and their receptors and inactivation of tumor-suppressor proteins are known to cause cell transformation and proliferation. The objectives of this study were to evaluate the expression of these factors in juvenile respiratory papillomas with correlation to cellular proliferation activity, and to determine whether such expression is associated with the clinical course of the disease. The expression of transforming growth factor-alpha, epidermal growth factor receptor, p53 protein, retinoblastoma proteins and Ki-67 was quantified by immunohistochemistry in paraffin-embedded biopsy specimens taken at the initial surgical excision from children in whom respiratory papillomatosis was diagnosed. Clinical information regarding the number of disease sites, tracheobronchial spread, malignant transformation, and frequency of recurrences was reviewed. Thirty-five specimens were suitable for immunohistochemical evaluation. Ki-67 expression was significantly higher in patients with multiple sites of disease and frequent recurrences. High p53 expression was significantly associated with malignant transformation. We concluded that Ki-67 and p53 expression may be predictive of the clinical course in children with respiratory papillomatosis.

Spontaneous respiration anesthesia for respiratory papillomatosis

Several anesthetic techniques for microlaryngeal laser surgery in children have been advocated. The objective of this study was to evaluate the operative conditions and safety of the spontaneous respiration anesthesia technique for carbon dioxide laser surgery in children with recurrent respiratory papillomatosis (RRP). The anesthetic and operative records of 60 pediatric patients with RRP who underwent microlaryngeal laser surgeries between 1991 and 1997 were reviewed. Papilloma location, severity of involvement, oxygen saturation, airway stability, need for intubation, duration of procedure, and complications were recorded. The patients underwent 744 surgical procedures. Two hundred two procedures were randomly studied (statistical power > or = 80%). The supraglottis and glottis were most commonly involved. Most of the papillomas were graded as moderate or severe disease. Complications occurred in 11 procedures. The surgical procedure was completed in all cases. No variable had predictive value regarding the outcome. Spontaneous respiration anesthesia is an efficient and relatively safe technique for microlaryngeal laser surgery in children with RRP.

Familial aggregation of Alzheimer disease among whites, African Americans, and Caribbean Hispanics in northern Manhattan

BACKGROUND

Alzheimer disease (AD) aggregates in families.

OBJECTIVE

To compare the familial aggregation and lifetime risk of AD to the age of 90 years in the first-degree relatives of patients with AD and unrelated controls among Caribbean Hispanics, African Americans, and whites in Washington Heights, Manhattan, New York, NY.

METHODS

Family history of AD and demographic information were obtained from informants of 435 patients with probable or possible AD concerning 1577 siblings and parents and from 1094 controls without dementia concerning 3952 siblings and parents.

RESULTS

Lifetime risk of AD to the age of 90 years was 25.9% in relatives of patients and 19.1% in relatives of controls. Rate ratio (RR) for AD in relatives of patients compared with relatives of controls was 1.5 overall (95% confidence interval [CI], 1.2-1.9), and was greater for siblings (RR, 1.8; 95% CI, 1.2-2.5) than for parents (RR, 1.2; 95% CI, 0.9-1.8). Within ethnic groups, RR for AD among relatives was significantly elevated in whites (RR, 2.0; 95% CI, 1.2-3.3) and Hispanics (RR, 1.5; 95% CI, 1.1-2.1), but the difference did not reach statistical significance in African Americans (RR, 1.4; 95% CI, 0.7-2.7). Risk of AD was greater among relatives who were women compared with men (RR, 1.5; 95% CI, 1.2-1.9).

CONCLUSIONS

Familial aggregation of AD was increased among families of patients compared with those of controls in all 3 ethnic groups. Risk of AD was highest among siblings and women relatives.

Rate of memory decline in AD is related to education and occupation: cognitive reserve?

OBJECTIVE

To determine whether the rate of decline in performance on a memory test is more rapid in AD patients with higher versus lower educational and occupational attainment.

BACKGROUND

Epidemiologic and imaging studies have suggested that, given comparable clinical severity of dementia, AD pathology is more advanced in patients with higher educational and occupational attainment. Because educational and occupational attainment should not influence the progression of AD pathology, and because severe AD pathology will eventually produce a mortality-causing condition, people with higher attainment might experience clinical AD for a shorter time and have a more rapid clinical progression.

METHODS

A total of 177 AD patients were tested yearly for up to four study visits with the Selective Reminding Test (a memory test). Analysis of prospective change in the total recall score was performed by applying generalized estimating equations to regression analyses with repeated measures.

RESULTS

At the initial visit, scores were comparable in the high- and low-education and the high- and low-occupation groups. Overall, memory scores declined by approximately 1 point yearly (p<0.01). There was a more rapid decline in memory scores in patients with higher educational (p<0.057) and higher occupational attainment (p<0.02). The authors then stratified patients based on their initial memory scores. The more rapid decline in memory scores associated with higher educational and occupational attainment was noted only in the group with low initial scores (p<0.05 for both). The full group and stratified group analyses were also repeated controlling for other potentially relevant variables including age, gender, race, ethnicity, and the presence of extrapyramidal signs, stroke, or at least one apolipoprotein E-epsilon4 allele. The results remained unchanged.

CONCLUSIONS

Memory declined more rapidly in AD patients with higher educational and occupational attainment. This adds support to the idea that the discontinuity between the degree of AD pathology and the observed clinical severity of AD is mediated through some form of reserve.

Protective effect of 3-aminobenzamide, an inhibitor of poly (ADP-ribose) synthetase, against laryngeal injury in rats

The effect of 3-aminobenzamide, an inhibitor of poly (ADP-ribose) synthetase activity, was evaluated in a rat model of laryngeal injury induced by endotracheal intubation for 1 h. At 1 h after extubation, the laryngeal damage was characterized by areas of mucosal necrosis, submucosal edema, swelling of subglottic glands, and submucosal infiltration of inflammatory cells. Activity of myeloperoxidase, a marker of neutrophil infiltration, was also markedly increased into the damaged tissue. Immunohistochemistry for nitrotyrosine, an index of nitrosative stress, showed an intense staining in the inflamed larynx. Treatment with 3-aminobenzamide (10 mg/kg intraperitoneally) significantly reduced the appearance of mucosal damage and was associated with a significant reduction of tissue myeloperoxidase activity and nitrotyrosine immunoreactivity in the larynx. The results of this study suggest that poly (ADP-ribose) synthetase may play a role in the inflammatory process after laryngeal intubation and extubation, and administration of 3-aminobenzamide may be a beneficial therapeutic approach.