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Biomedical subjects

Y Stern

Publications and source records attributed to Y Stern.

At least 163 records · Page 9Linked to original sources
PubMed1995

Clinical correlates of Alzheimer's disease with and without silent radiographic abnormalities.

OBJECTIVE: To determine whether patients with Alzheimer's disease (AD) who do not have historical or clinical evidence of stroke but who do have computed tomographic or magnetic resonance imaging evidence of noncortical lesions smaller than 2 cm or periventricular "caps" differ from other patients with AD. METHODS: The computed tomographic or magnetic resonance imaging scans of 158 patients meeting criteria of the National Institute of Neurological Disorders and Stroke-Alzheimer's Disease and Related Disorders Association for probable AD were reviewed by one neuroradiologist. Two measures of disease severity--the Modified Mini-Mental State examination and the Blessed Dementia Rating Scale (Part I)--were subjected to two-way analysis of variance with scan type (computed tomography or magnetic resonance imaging) and lesion number as between-group factors and age and disease duration as covariates. RESULTS: No relationship was seen between lesion number or periventricular caps and disease severity. CONCLUSION: In this cross-sectional analysis using these clinical measures, patients with AD who have well-defined radiographic abnormalities cannot be differentiated from patients with AD who do not have them.

Adult↗
PubMed1995

Neuropsychologic impairment in early HIV infection. A risk factor for work disability.

OBJECTIVE: To explore the functional significance of incident neuropsychologic impairment among initially asymptomatic subjects infected with human immunodeficiency virus. DESIGN: Prospective, observational cohort study of homosexual and bisexual men to examine the incidence of work disability related to the onset of neuropsychologic impairment. SETTING: A university clinical and behavioral research site in New York City. PARTICIPANTS: Sample of 207 homosexual and bisexual men; 123 were seropositive and 84 were seronegative. PRINCIPAL OUTCOME MEASURES: Incident work disability in the course of 4.5 years of follow-up, with disability defined as a persistent (> or = 24 months) change in work hours (from 20 or more to less than 20 h/wk). RESULTS: Compared with seronegative control subjects (n = 72), the relative risk of work disability among initially asymptomatic seropositive men (n = 44) was 2.76 (95% confidence interval, 1.2 to 6.5), nearly a threefold increase. Proportional hazards models show that this increased risk is attributable to the development of major neuropsychologic impairment in a subset (eight of 44) of the initially asymptomatic men, which is significantly associated with incident work disability (6/8 [75%]). Adjusting for symptom status and CD4+ cell count at the time of disability did not eliminate the increased risk associated with neuropsychologic impairment. CONCLUSIONS: In this cohort, the increased risk of work disability among initially asymptomatic human immunodeficiency virus-positive men was related to incident neuropsychologic impairment; such impairment predicted work disability independently of symptom status and CD4+ cell count over the follow-up period. Neuropsychologic impairment in the course of human immunodeficiency virus infection may indicate increased risk for poor outcomes over and above that associated with systemic disease.

Cohort Studies↗
PubMed1995

Cerebral single-photon emission computed tomography abnormalities in human immunodeficiency virus type 1-infected gay men without cognitive impairment.

OBJECTIVE: To determine whether technetium Tc99m exametazime single-photon computed emission tomography (SPECT) can distinguish gay human immunodeficiency virus (HIV)-positive subjects, both with and without mild cognitive impairment, from gay HIV-negative control subjects. DESIGN: Twenty HIV-positive subjects (12 without cognitive impairment and eight with mild cognitive impairment) and 10 HIV-negative subjects underwent neurological, neuropsychological, magnetic resonance imaging, and technetium Tc 99m exametazime SPECT examinations. SETTING: Subjects were recruited from a natural history study of gay men with HIV infection. PATIENTS: Subjects from the cohort who had previously participated in a magnetic resonance imaging study were selected for the SPECT study. MAIN OUTCOME MEASURES: The SPECT scans were rated as abnormal if focal defects, confirmed by a horizontal profile analysis, were seen. RESULTS: Sixty-seven percent of HIV-positive subjects without cognitive impairment, 88% of HIV-positive subjects with mild cognitive impairment, and 20% of HIV-negative subjects had abnormal SPECT scans (P < .05 for both HIV-positive groups when each group was compared with HIV-negative subjects). CONCLUSION: Compared with gay HIV-negative control subjects, focal SPECT defects are seen with an increased frequency in HIV-positive gay men without cognitive impairment and in HIV-positive gay men with mild cognitive impairment.

AIDS Dementia Complex↗
PubMed1995

Serum neopterin level predicts HIV-related mortality but not progression to AIDS or development of neurological disease in gay men and parenteral drug users.

OBJECTIVE: To investigate the ability of elevated serum neopterin levels to predict independently mortality, progression to acquired immunodeficiency syndrome, and development of neurological disease. DESIGN: Cross-sectional and longitudinal study of gay and/or bisexual men and parenteral drug users. SETTING AND PATIENTS: Patients included human immunodeficiency virus (HIV)-negative and -positive gay and/or bisexual men and parenteral drug-using men and women who volunteered for an outpatient study of the natural history of HIV infection. RESULTS: Serum neopterin levels were significantly elevated in HIV-positive patients (mean, 18.0 nmol/L; SD, 19.2 nmol/L), compared with those in HIV-negative patients (mean, 7.5 nmol/L; SD, 5.5 nmol/L) (P < .001). No differences in the serum neopterin levels could be detected between gay men and parenteral drug users. In HIV-positive patients, women had a higher serum neopterin level than did men (P = .03). The elevated serum neopterin levels were associated with an advanced clinical stage of HIV infection. After adjusting for the CD4 lymphocyte count and other potential confounders, the serum neopterin level was a significant independent predictor of mortality. The elevated serum neopterin levels did not predict progression to acquired immunodeficiency syndrome or development of clinically significant neurological disease. CONCLUSION: An elevated serum neopterin level predicts mortality, but it does not predict progression to acquired immunodeficiency syndrome or development of neurological disease among HIV-infected individuals.

Acquired Immunodeficiency Syndrome↗
PubMed1995

The frequency and associated risk factors for dementia in patients with Parkinson's disease.

OBJECTIVES: To estimate the frequency and determine the risk factors for incident dementia in community-dwelling patients with Parkinson's disease (PD) and in control subjects. DESIGN: Prospective cohort study. During a 3.5-year period, 140 patients with idiopathic PD without evidence of dementia and 572 nondemented control subjects were identified in the community of Washington Heights-Inwood in New York, NY. All subjects underwent neurological and neuropsychological evaluations and follow-up examinations. RESULTS: Twenty-seven patients with PD (19.2%) became demented throughout 2 years, as compared with 87 (15.2%) of the control subjects. The relative risk (RR) for the development of dementia with PD was 1.7 (95% confidence interval [CI], 1.1 to 2.7) after adjusting for age, education, and gender. Predictive features of incident dementia were an extrapyramidal score greater than 25 (RR, 3.56; 95% CI, 1.4 to 8.9) and a Hamilton Depression Rating Scale score greater than 10 (RR, 3.55; 95% CI, 1.6 to 7.9). CONCLUSION: Patients with PD, especially those with severe extrapyramidal signs, have almost twice the risk for the development of dementia than do community-dwelling control subjects.

Aged↗
PubMed1995

A comparison of cerebral SPECT abnormalities in HIV-positive homosexual men with and without cognitive impairment.

OBJECTIVE: To determine whether technetium Tc 99m exametazime (HMPAO) single-photon emission computed tomography (SPECT) can distinguish between human immunodeficiency virus (HIV)-positive homosexual men with normal neuropsychologic test results and HIV-positive homosexual men with abnormal neuropsychologic test results. DESIGN: Neurologic, neuropsychologic, magnetic resonance imaging, and Tc 99m HMPAO SPECT examinations were performed on 10 HIV-positive homosexual men without cognitive impairment and five HIV-positive homosexual men with cognitive impairment. PATIENTS: Human immunodeficiency virus-positive homosexual men from New York City were recruited for the study. MAIN OUTCOME MEASURES: Findings on SPECT scans were evaluated qualitatively for focal defects, heterogeneity of the cortical margin, white matter hypoperfusion, and decreased global cortical uptake. All SPECT focal defects were coregistered with magnetic resonance images; SPECT heterogeneity and global cortical uptake were also measured quantitatively. RESULTS: Coregistration with magnetic resonance imaging revealed that 63% of the focal SPECT defects corresponded to brain gyri and 37% corresponded to sulci. There was no significant difference in the frequency of qualitative or quantitative SPECT abnormalities between HIV-positive homosexual men ith and without cognitive impairment. However, after examining individual neuropsychologic test factors, impaired motor speed performance was associated with decreased quantitative global cerebral uptake. CONCLUSIONS: Qualitative SPECT abnormalities are not increased in frequency in HIV-positive homosexual men with global cognitive impairment compared with those in HIV-positive homosexual men without cognitive impairment. Impaired motor speed performance may be associated with decreased quantitative global cerebral uptake.

Adult↗
PubMed1995

Risk of human immunodeficiency virus type 1-related neurologic disease in a cohort of intravenous drug users.

BACKGROUND: Although the proportion of cases of acquired immunodeficiency syndrome related to intravenous drug use has increased dramatically over the past decade, there has been no longitudinal examination of primary neurologic disease in this group. OBJECTIVE: To study the development of neurologic disease in human immunodeficiency virus (HIV)-negative and HIV-positive men and women who were intravenous drug users over a 3.5-year period. DESIGN: Prospective observational cohort study. SETTING: Subjects were recruited from an infectious disease clinic at a New York City Hospital or from a methadone maintenance program. PARTICIPANTS: Ninety-nine HIV-negative (62 men and 37 women) and 124 HIV-positive (85 men and 39 women) intravenous drug users volunteered. MAIN OUTCOME MEASURE: The development of clinically significant manifestations in six neurologic domains. RESULTS: With multivariate adjustment for current and past substance abuse, age, education, and head injury, we examined the odds of developing HIV-related neurologic disease. Extrapyramidal signs and reduced motor ability became increasingly apparent over time in HIV-infected men as their CD4 cell count declined and as the subjects developed the acquired immunodeficiency syndrome. Fewer neurologic signs were seen in the women. CONCLUSIONS: The impact of HIV infection among intravenous drug users parallels that in homosexual men and is independent of alcohol and other drug use.

Adult↗
PubMed1995

Significance of DNA ploidy in the treatment of T1 glottic carcinoma.

OBJECTIVE: To assess the role of DNA ploidy as a predictor of radioresistance in T1 glottic carcinoma. DESIGN: Case-control study. Flow cytometric DNA ploidy measurements were performed on formalin-fixed paraffin-embedded tumor specimens from 15 patients with T1 glottic laryngeal carcinomas in whom radiotherapy had failed and from a matched group of 15 patients in whom an identical radiotherapy regimen was curative. Analysis of DNA content was performed blind to outcome of treatment. SETTING: Academic tertiary referral medical center. PARTICIPANTS: Thirty patients with clinically staged T1, N0, M0 glottic carcinoma. INTERVENTION: All patients received radiation to the larynx through opposed lateral ports at a total dose of 64 to 70 Gy. RESULTS: Ten diploid and five aneuploid histograms were found in the resistant group, and six diploid and nine aneuploid histograms were found in the radiosensitive group. This difference was not statistically significant. A trend toward a higher relapse rate after radiotherapy (62.5%) among patients with diploid tumor compared with those with aneuploid tumor (35.7%) was noted. CONCLUSIONS: DNA ploidy did not predict response to radiotherapy in patients with T1 glottic cancer, probably because of the small number of patients. A trend toward lower risk of local recurrence after radiotherapy in aneuploid tumors was noted. A larger prospective study is needed to assess the value of DNA ploidy in the treatment of early laryngeal cancer.

Aged↗
PubMed1995

Apolipoprotein E and Alzheimer's disease: ethnic variation in genotypic risks.

The presence of the apolipoprotein epsilon 4 (apo epsilon 4) allele significantly increases the risk of Alzheimer's disease. Whether this is due to biological effects of the apo epsilon 4 protein or reflects linkage disequilibrium with an as yet unidentified Alzheimer's disease susceptibility gene is of critical importance. In a community study in northern Manhattan we found a fivefold increase in the risk of Alzheimer's disease among African-Americans, Hispanics, and whites homozygous for apo epsilon 4. Overall, the risk between Alzheimer's disease and apo epsilon 4 heterozygosity was also increased by twofold, but the association was somewhat weaker for African-Americans than for Hispanics and whites. In contrast, the apo epsilon 2/epsilon 3 genotype was associated with an eightfold increased risk of Alzheimer's disease in African-Americans but it was associated with reduced risk in whites. Variability in the strength and type of association between Alzheimer's disease and the apo E polymorphisms in the three ethnic groups could not be fully explained by age differences. The allelic frequency of apo epsilon *4 was significantly higher in patients than control subjects in all ethnic groups at age 70 or younger, reflecting the higher proportion of apo epsilon 4 homozygotes, but this difference diminished with increasing age. The allelic frequency of apo epsilon *2 for African-Americans and Hispanics, but not whites, was significantly higher in patients than control subjects, but only after age 70.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Increased risk of mortality in Alzheimer's disease patients with more advanced educational and occupational attainment.

A reserve hypothesis suggests that clinical symptoms of Alzheimer's disease (AD) begin earlier in individuals with less education. Therefore, patients with less education might survive longer after diagnosis than those with more education. Two hundred forty-six subjects with probable AD were followed for 1 to 4 years. There were 78 deaths; 30 deaths occurred in the 127 patients whose education was < or = 8 years, while 48 deaths occurred in the 119 patients with > 8 years of education. Cox proportional hazards models adjusted for age, gender, and clinical dementia rating (CDR) showed that patients with more education had increased mortality (continuous variable: RR = 1.06 for each year of education; 95% confidence interval [CI], 1.01-1.11; dichotomous variable at 8 yr: RR = 1.76; CI, 1.11-2.77). This observation might at first seem counterintuitive, since groups with lower socioeconomic status are often at greater mortality risk. It implies that at any level of assessed clinical severity, the underlying pathology of AD is more advanced in patients with more education, resulting in shorter duration of diagnosed disease before death. These findings suggest either that education systematically influences global ratings of disease severity or that education provides a reserve against the clinical manifestation of AD pathology.

Aged↗
PubMed1995

Simple reaction time as a measure of global attention in Alzheimer's disease.

Alzheimer's disease (AD) is characterized by progressive decline in memory, language and other cognitive functions. Deficits in attentional processes have also been suggested. A simple reaction time (RT) task was used to assess global attention in AD. The length and consistency of a warning signal given prior to the response stimulus were manipulated to determine if patients with AD and age-matched controls benefit from predictability in RT tasks. Overall reaction time was slower in the AD group than in the and control group. Both groups demonstrated significant improvement in RT with long warning signals compared to short warning signals, but only the control group benefited from the consistency of the warning.

Aged↗
PubMed1995

Mucormycosis: experience with 10 patients.

Rhinocerebral mucormycosis is a fulminating, devastating fungal disease, usually associated with debilitating diseases such as diabetes mellitus, leukaemia and immunosuppressive conditions. Ten patients with this rare disease have been treated over the past 14 years at the Beilinson Medical Centre. Nine patients had an underlying debilitating disease and one patient had latent diabetes mellitus which was diagnosed only after presentation of mucormycosis. Only two of the 10 patients survived. Early aggressive surgical debridement, together with amphotericin B and correction of underlying metabolic acidosis were found to be important factors associated with survival.

Adult↗
PubMed1995

Cortical perfusion and gray matter weight in frontal lobe dementia.

To evaluate the pathophysiology of frontal lobe dementia (FLD), the authors compared regional cerebral blood flow (rCBF) in matched groups of FLD, probable Alzheimer's disease (AD), and major depression patients and normal control subjects (n = 7 each). The planar xenon-133 technique allowed full quantification of cortical perfusion and estimates of the relative weight of gray matter (wg). FLD patients showed lower blood flow and wg in the frontal cortex than the other groups. Mean cortical perfusion was correlated with cortical wg in the FLD group only. These findings 1) suggest that matched reductions of frontal gray matter weight and perfusion occur in FLD and 2) support the use of rCBF in distinguishing FLD from AD and severe depression.

Aged↗
PubMed1995

Vocal cord palsy: possible late complication of radiotherapy for head and neck cancer.

Cranial nerve palsies are uncommon complications of radiotherapy for head and neck cancer. A review of the literature reveals that cranial nerve damage after radiotherapy has been reported for the optic, oculomotor, trigeminal, abducens, cochlear, vagus, spinal accessory, and hypoglossal nerves. The hypoglossal nerve appears to be the most commonly affected, and the recurrent laryngeal nerve is seldom involved. The case histories of three patients who developed vocal cord palsy from 21 to 34 years after a course of curative or postoperative radiotherapy for carcinoma of the head and neck are presented. Two patients had bilateral palsy, and in the third patient, bilateral damage cannot be excluded. Physical examination and radiographic investigations on admission and on follow-up did not demonstrate any evidence of tumor recurrence, cervical or distant metastases, or second primary tumors. The distinction between irradiation-induced palsy and that due to malignancies is emphasized.

Adolescent↗
PubMed1995

Relationship between lifetime occupation and parietal flow: implications for a reserve against Alzheimer's disease pathology.

We previously reported an inverse relation between parietal cerebral blood flow and years of education in Alzheimer's disease (AD) patients matched for clinical severity. This suggested that the clinical manifestation of advancing AD pathology is delayed in patients with higher educational attainment. Other aspects of life experience may also provide a reserve against the clinical expression of AD. To test this hypothesis, we classified the primary life-time occupations of 51 AD patients using the Dictionary of Occupational Titles, published by the US Department of Labor, and derived six factor scores describing intellectual, interpersonal, and physical job demands. Regional cerebral blood flow was measured using the xenon-133 inhalation method. After controlling for age, clinical dementia severity, and education, there was less relative perfusion in the parietal region in subjects whose occupations were associated with higher interpersonal skills and physical demands factor scores. We conclude that independent of education, aspects of occupational experience may provide a reserve that delays the clinical manifestation of AD.

Administration, Inhalation↗
PubMed1995

Consistency of clinical diagnosis in a community-based longitudinal study of dementia and Alzheimer's disease.

We evaluated the consistency of the diagnosis of dementia in a multicultural, longitudinal community-based study of cognitive impairment and dementia. We diagnosed dementia using a fixed neuropsychological paradigm; the diagnosis also required historical evidence of functional impairment. In a sample of 656 subjects with at least one annual follow-up examination, dementia was confirmed at 1 year in 89% of the 304 subjects initially demented, and in 90% of the 136 subjects with the initial diagnosis of probable Alzheimer's disease (AD). The 34 initially demented subjects who failed to meet criteria for dementia at follow-up included 13 with an initial diagnosis of probable AD. All 34 still had evidence of cognitive impairment; this group was more likely to have a history of pulmonary disease, multiple medication use, or chronic alcohol use than other demented patients. Consistency of dementia diagnosis did not vary according to educational attainment or ethnic background. The use of a neuropsychological paradigm such as ours in large longitudinal studies of dementia may minimize interobserver diagnostic variability or diagnostic drift over time while contributing the benefits of a comprehensive cognitive evaluation to the diagnostic process.

Aged↗
PubMed1995

Neuropsychological test performance in African-American and white patients with Alzheimer's disease.

Little information exists on the performance of black versus white patients with Alzheimer's disease on neuropsychological tests for dementia. In this study, we compared performance on the CERAD (Consortium to Establish a Registry for Alzheimer's Disease) neuropsychological battery between white (n = 830) and black (n = 158) patients with Alzheimer's disease enrolled in the CERAD study at 23 university medical centers in the United States. The black patients were older, had fewer years of formal education, and were more impaired in their activities of daily living than were the white patients. After controlling for these characteristics and for duration of the disease and severity of dementia, there were differences in the performance of black and white patients on several of the cognitive measures. Black patients scored lower than whites on tests of visual naming and constructional praxis and on the Mini-Mental State Examination. There were no statistical differences in performance on tests of fluency and word list memory. These findings suggest that cultural or experiential differences may modify performance on specific neuropsychological tests. These factors, in addition to age and educational background, should be considered when interpreting performance on neuropsychological tests in elderly black patients with dementia.

Black or African American↗