Biomedical subjects

E Kokmen

Publications and source records attributed to E Kokmen.

At least 55 records · Page 3Linked to original sources

PubMed1997

Risk of Alzheimer's disease among elderly patients with anemia: population-based investigations in Olmsted County, Minnesota.

PURPOSE: To evaluate the association, if any, between Alzheimer's disease (AD) and anemia among the elderly. METHODS: Both case-control and cohort methodologies were used to evaluate this association. The case-control study included all incident cases of AD whose onset occurred during 1980-1984 in Rochester, MN (n = 302). An age- and gender-matched control was selected from among Rochester residents seen for care at Mayo Clinic during the year of onset of the case. All community medical records for cases and controls were reviewed to identify women with hemoglobin levels of < 12 g/dL and men with hemoglobin levels of < 13 g/dL during the year of onset and the prior year for cases and during the index year and year prior for controls. Logistic regression was used to estimate odds ratios (OR). The retrospective cohort study used the 618 residents of Olmsted County, MN, who were > or = 65 years of age and whose anemia, as defined above, was newly recognized in 1986. Standardized incidence ratios (SIR) for AD were estimated by use of the person-years of follow-up in the cohort and the incidence rates of AD for this community. RESULTS: In the case-control study, an almost twofold increase in occurrence of AD was associated with anemia (OR, 1.88; 95% CI, 1.17-3.03). For men and women, respectively, the ORs were 1.81 (95% CI, 0.75-4.39) and 1.96 (95% CI, 1.11-3.47). The cohort study showed no overall increase in risk of AD (SIR, 0.98; 95% CI, 0.67-1.37). For men, the SIR was a comparable 1.49 (95% CI, 0.79-2.56), whereas for women the SIR was only 0.79 (95% CI, 0.49-1.23). CONCLUSIONS: Although anemia may be a risk factor for AD in the elderly, the mechanism by which anemia contributes to the pathogenesis of AD or to the unmasking of AD symptoms is unknown.

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PubMed1997

Aging, memory, and mild cognitive impairment.

In recent years, patients who are at high risk for developing Alzheimer's disease (AD) have become a focus of study. Several research groups have identified these patients, developed diagnostic criteria, and followed the patients longitudinally. These patients therefore constitute a clinical entity that is suitable for therapeutic interventions. In this article, we report our 5-year experience at the Mayo Clinic in characterizing a group of patients with mild cognitive impairment. These subjects were recruited from community-dwelling individuals who were receiving general medical care in the Department of Internal Medicine. They received the diagnosis of mild cognitive impairment if they met the following criteria: (a) complaint of defective memory, (b) normal activities of daily living, (c) normal general cognitive function, (d) abnormal memory function for age, and (e) absence of dementia. In following more than 75 of these patients, some of whom have been studied for as long as 5 years, it appears that approximately 10% to 15% of the subjects evolve to AD each year. We therefore evaluated the cognitive profiles of these patients at the time of their initial diagnosis in an attempt to predict who would remain stable and who would evolve to AD. Certain features of learning and memory performance indicated patients who were more likely to progress, but the strongest predictor was their apolipoprotein E status. The patients who possessed an epsilon 4 allele were more likely to convert to AD at a more rapid rate then those who were not carriers. Our results and similar data from other study groups indicate that diagnostic criteria can be defined for patients who are likely to convert to AD; the natural history of these patients is becoming apparent, and variables that predict ultimate conversion can be defined. Consequently, patients with mild cognitive impairment constitute an important group for study, particularly form the aspect of therapeutic interventions.

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PubMed1997

Free and cued selective reminding test: MOANS norms.

Age-adjusted norms are presented for persons age 56-98 years on the Free and Cued Selective Reminding Test (FCSRT; Buschke, 1984; Grober & Buschke, 1987). These data were obtained via several research projects that are known collectively as Mayo's Older Americans Normative Studies (MOANS). These norms should be useful when the FCSRT is used as a "stand alone" test. They should also promote accuracy in the comparison of any person's FCSRT performance against his or her functioning on any other tests with MOANS norms. The unique features of the FCSRT are discussed. These norms will, hopefully, enhance the utility of the test when it is used in clinical and research investigations of various amnestic disorders.

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PubMed1997

Comorbidity of dementia and psychiatric disorders in older persons.

To further investigate the relationship between psychiatric disorders and dementia in elderly patients, the authors drew a population-based, age-stratified random sample from residents of Rochester, Minnesota, age 65 and older. A trained paramedic completed a 90-minute screening interview, including the Symptom Checklist-90, Mini-Mental State Exam, and Auditory-Verbal Learning Test. Persons failing the screens were interviewed by a psychiatrist and a neurologist. DSM-III-R diagnoses were assigned for dementia and other psychiatric disorders. Of 201 participants, 37 were evaluated further by both neurologist and psychiatrist. One received a psychiatric diagnosis alone. Dementia alone was present in four people. Concurrent psychiatric diagnoses and dementia were found in 17 subjects. Much of the psychopathology found in older persons occurs in people with cognitive impairment. Current diagnostic nosology may not be able to capture the interrelatedness of psychiatric syndromes and cognitive impairment in elderly patients.

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PubMed1997

Medial temporal atrophy on MRI in normal aging and very mild Alzheimer's disease.

Magnetic resonance imaging (MRI)-based volumetric measurements of medial temporal lobe (MTL) structures can discriminate between normal elderly control subjects and patients with Alzheimer's disease (AD) of moderate to advanced severity. In terms of clinical utility, however, a more important issue concerns the ability of the technique to differentiate between normal elderly control subjects and AD patients with the very mildest form of the disease. We performed MRI-based volumetric measurements of the hippocampus, parahippocampal gyrus, and amygdala in 126 cognitively normal elderly control subjects and 94 patients with probable AD. The diagnosis of AD was made according to NINDS/ADRDA criteria, and disease severity was categorized by Clinical Dementia Rating (CDR) scores. Patients with CDR 0.5 were classified as very mild, CDR 1 as mild, and CDR 2 as moderate disease severity. Volumes of each structure declined with increasing age in control subjects and did so in parallel for men and women. The volume of each measured MTL structure also declined with age in patients with AD. The volume of each MTL structure was significantly smaller in AD patients than control subjects (p < 0.001). Of the several MTL measures, the total hippocampal volumetric measurements were best at discriminating control subjects from AD patients. The mean hippocampal volumes for AD patients relative to control subjects by severity of disease were as follows: very mild AD (CDR 0.5) -1.75 SD below the control mean, mild AD (CDR 1) -1.99 SD, and moderate AD (CDR 2) -2.22 SD. Age- and gender-adjusted, normalized MRI-based hippocampal volumetric measurements provide a sensitive marker of the MTL neuroanatomic degeneration in AD early in the disease process.

Aging↗

PubMed1996

Plasma catechols and monoamine oxidase metabolites in untreated Parkinson's and Alzheimer's diseases.

Prior studies have documented functional and pathological compromise of the peripheral sympathetic nervous system in patients with Parkinson's disease, suggesting the possibility of reduced catecholamine release into the circulation. We measured free plasma catechols in early and untreated patients with Parkinson's disease, but found no evidence of reduced concentrations, compared to control subjects or a group of patients with probable Alzheimer's disease. Rather, there was a significant elevation of plasma norepinephrine within the Parkinson's disease group. Furthermore, 6 of 15 untreated Parkinson's disease patients (40%) displayed markedly elevated plasma concentrations of the catecholamine MAO metabolites, DOPAC or DOPEG. Despite this finding, platelet MAO-B activity measured in these and all other Parkinson's disease patients fell well within the range of the control subjects, and was also statistically similar to the group with Alzheimer's type dementia. Plasma dopa levels were similar in all groups, whereas the majority of patients in the three groups had plasma free dopamine and epinephrine concentrations below the limits of detection. These trends toward increased, rather than decreased, circulating catechol concentrations suggest that peripheral sympathetic nervous system catecholamine production and release is not severely compromised in patients with early Parkinson's disease. In addition, we were unable to confirm certain previous reports of elevated MAO-B activity in patients with Parkinson's or Alzheimer's diseases.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1996

Impact of referral bias on clinical and epidemiological studies of Alzheimer's disease.

We used the resources of the Rochester Epidemiology Project to compare sociodemographic and clinical characteristics in three groups of Alzheimer's disease patients. The first group included incidence cases occurring among residents of Rochester, Minnesota (population-based series; n = 241). The second group was a sample of patients referred to the Mayo Clinic form the remainder of Minnesota and the four surrounding states (n = 58); the third was a sample referred from the remainder of the United States (n = 94). Patients from Rochester were more frequently women, less highly educated, less commonly white collar workers, more frequently institutionalized, less frequently married, and more often lived along than those in the two referral groups. Patients from Rochester also had a more advanced age of onset of dementia. For occupation, education, and living arrangement, the differences across groups increased with increasing distance of referral. Clinical and epidemiological studies based on patients referred form primary to secondary or tertiary care centers may suffer from severe selection bias.

Adult↗

PubMed1996

Cause of death in Alzheimer's disease.

Cause of death among 917 of the 959 subjects in a population-based incidence cohort with Alzheimer's disease (AD) during the years 1960 to 1984 was compared to that of an age- and gender-matched control group (n = 703). In general, a summary of the diagnostic codes entered anywhere on a death certificate suggests that control subjects had more cardiovascular disease and neoplasms than did patients, while patients more often had a diagnostic code of bronchitis/pneumonia (P < 0.01). By logistic regression, this difference remained statistically significant after adjusting for age and gender.

Alzheimer Disease↗

PubMed1996

Prior intra-operative hypotension is not a risk factor for development of Alzheimer's disease.

OBJECTIVE: A retrospective, population-based, case-control study was carried out to evaluate episodes of prior intra-operative hypotension as a potential risk factor for Alzheimer's disease (AD). METHODS: Patients were all incident cases of AD from 1975-1984 who resided for 40 years or more in Olmsted County prior to their onset of dementia (N = 252). One age and gender-matched control for each case was selected from all registrations for care at Mayo Clinic during the year of onset in the incident case. Each case and control group had 252 individuals. RESULTS: Of these, 27 cases and 32 controls had at least one ten minute or longer episode of intra-operative hypotension of a systolic blood pressure of less than 90 mm Hg prior to the year of onset of dementia in the matched AD patient. We did not find a significantly increased risk of AD for hypotensive episodes of less than 75 or 90 mm Hg. CONCLUSIONS: It is unlikely that intra-operative hypotensive events of this degree increase the risk of AD.

Alzheimer Disease↗

PubMed1996

Dementia after ischemic stroke: a population-based study in Rochester, Minnesota (1960-1984)

We used the medical records linkage system for the population of Rochester, Minnesota, to identify persons in the community who had their first cerebral infarct without previous dementia. In this cohort (n = 971), the incidence of dementia in the first year was nine times greater than expected, but if we did not observe dementia in the first year, the risk of dementia in the cohort each year thereafter was about twice the risk in the population. After the first year, a 50% increase was observed in Alzheimer's disease in the cohort compared with that in the community. Although the incidence of dementia increased with increasing age, the standardized morbidity ratios decreased with increasing age. Age, sex (male), and second stroke were significant independent predictors of dementia in a multivariate Cox proportional hazards model. There was no effect of location or clinical severity of infarct on the rate of occurrence of dementia.

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PubMed1996

Dementia and adult-onset unprovoked seizures.

OBJECTIVE: We tested the hypothesis that dementia increases the risk of unprovoked seizure among adults. Partial- and generalized-onset seizures were considered together and separately. Additionally, we explored whether the increased risk was restricted to Alzheimer's disease (AD), as previously shown. DESIGN: Subjects in this population-based case-control study were 145 incident cases of first unprovoked seizure (without prior stroke, CNS infection, brain tumor, head trauma, mental retardation, or cerebral palsy) aged 55 years or older and 290 controls matched to cases on age, gender, and duration of medical follow-up. Using the records-linkage system of the Rochester Epidemiology Project, we obtained, for both cases and matched controls, information on dementia prior to onset of unprovoked seizure. Subjects were classified as having dementia if they met ad hoc criteria equivalent to those in the DSM-III. AD was distinguished from other dementias. RESULTS: Both a diagnosis of AD and a diagnosis of other dementia were associated with at least a six-fold increased risk of unprovoked seizure when controlling for age, sex, and length of medical follow-up in Rochester. There was no difference in risk when comparing generalized-onset seizures with partial-onset seizures. CONCLUSIONS: In the absence of other prior neurologic insult, both AD and other dementias increase the risk of generalized- and partial-onset unprovoked seizures.

Age of Onset↗

PubMed1996

Epidemiology of dementia in Rochester, Minnesota.

OBJECTIVE: To present the results of several retrospective epidemiologic studies of dementia in Rochester, Minnesota. MATERIAL AND METHODS: These studies were done by using the medical records-linkage resources of the Rochester Epidemiology Project. RESULTS: The incidence and prevalence of dementia increase sharply with advancing age. No difference is noted in overall age-adjusted incidence rates by gender. Rochester studies provide the only 25-year time trend analyses of the incidence of dementia in the United States. Time trends over three prevalence dates indicate an increase in prevalence in this community. Survival is decreased among patients with dementing illness. Case-control studies of Alzheimer's disease (AD) show that general medical conditions, previous head injury, thyroid disease, exposure to therapeutic radiation, anesthesia, and blood transfusion are generally not risk factors for AD. Patients with depression may have an increased risk for the development of AD. Sociodemographic factors such as education, occupation, marital status, and type of dwelling were not significantly different among patients with AD and their age-and gender-matched control subjects. CONCLUSION: The Rochester Epidemiology Project has proved to be an excellent resource for the study of the incidence, prevalence, and risk factors for dementia.

Adult↗

PubMed1996

The Mini-Mental State Examination in general medical practice: clinical utility and acceptance.

OBJECTIVE: To examine the psychometric properties, acceptance, and screening efficacy of the Mini-Mental State Examination (MMSE) in an internal medicine practice. MATERIAL AND METHODS: The MMSE was administered more than 4,000 times by 27 internists to 3,513 elderly patients (2,299 women and 1,214 men, 60 to 102 years old) who underwent general medical examinations. The efficacy of the MMSE for screening was measured in a subsample of age- and sex-matched patients with dementia (N = 185) and control subjects (N = 227). MMSE scores were correlated with age and education in the community sample. The attitudes of physicians about the MMSE were assessed with a 12-question survey. Sensitivity, specificity, and predictive values were calculated. RESULTS: Performance on the MMSE among persons older than 59 years was influenced by age and education but not by sex. During an interval of 1 to 4 years, a change of 4 or more points in the total MMSE score is needed to indicate substantial cognitive deterioration. Participating physicians considered the MMSE of little value for routine screening in unselected populations but wanted it available for use as a clinical test. The traditional MMSE cutoff score of 23 or less had a sensitivity of 69% and a specificity of 99%. Use of age- and education-specific cutoff scores improved the sensitivity to 82% with no loss of specificity. With use of typical base rates for dementia in a general medical practice, the positive predictive value was less than 35%. CONCLUSION: The clinical utility of the MMSE and acceptance by physicians may be improved through awareness of the influences of age and education on the MMSE and by its application in settings with a high base rate of dementia. The MMSE is ineffective when used to screen unselected populations; it should be used for persons at risk of cognitive compromise.

Age Factors↗

PubMed1995

Apolipoprotein E status as a predictor of the development of Alzheimer's disease in memory-impaired individuals.

OBJECTIVE: The outcome of patients with mild cognitive impairment is not known, yet these patients present a difficult dilemma for the clinician. This study was designed to characterize the outcome of a group of patients with mild cognitive impairment and to determine whether the presence of the epsilon 4 allele on the apolipoprotein E gene (APOE) is a predictor of that outcome. DESIGN: A prospective, longitudinal inception cohort. SETTING: General community clinic. PARTICIPANTS: A consecutive sample of 66 patients who met criteria for a diagnosis of a mild cognitive impairment and who had at least one clinical reevaluation was identified from the Mayo Clinic Alzheimer's Disease Center/Alzheimer's Disease Patient Registry. INTERVENTIONS: We evaluated patients initially and at 12- to 18-month intervals up to 54 months using standard neurological and neuropsychological measures such as the Mini-Mental State Examination, the Dementia Rating Scale, the Wechsler Adult Intelligence Scale--Revised, the Wechsler Memory Scale--Revised, and the Free and Cued Selective Reminding Test. The APOE status of study patients was determined. MAIN OUTCOME MEASURE: The development of dementia as determined by the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition and the National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association criteria. RESULTS: Sixty-six individuals had been reevaluated once (mean of 18 months), 36 individuals twice (mean of 36 months), and 22 individuals on three occasions (mean of 54 months), with conversion rates to dementia at these intervals of 24%, 44%, and 55%, respectively. A multivariate Cox regression model demonstrated that possession of an APOE epsilon 4 allele was the strongest predictor of clinical outcome. CONCLUSIONS: These data suggest the following: (1) patients with mild cognitive impairment can be clinically defined, (2) many members of this group progress to Alzheimer's disease, and (3) APOE epsilon 4 allele status appears to be a strong predictor of clinical progression.

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PubMed1995

No evidence for systemic oxidant stress in Parkinson's or Alzheimer's disease.

Oxidant stress secondary to dopamine metabolism has been proposed as a pathogenic factor in the development of Parkinson's disease. Biochemical abnormalities extending beyond the central nervous system have been identified in patients with this condition. Previous investigators have found abnormally elevated concentrations of the lipid peroxidation product, malondialdehyde, in the plasma and serum of patients with Parkinson's disease. We attempted to replicate these findings but controlled for other factors that could influence malondialdehyde levels. We detected no significant elevations in mean serum malondialdehyde concentrations in either levodopa-treated or untreated patients with Parkinson's disease, compared to normal controls; similarly, no elevation was found in a group of patients with dementia of Alzheimer's type. On the other hand, a group of subjects with diabetes mellitus but no neurodegenerative disease had significantly elevated mean serum malondialdehyde levels, consistent with previous studies of diabetic patients. Autoxidation is one of the two major routes by which dopamine and dopa metabolism may generate oxygen free radicals. We analyzed the autoxidation product of dopa, 5-S-cysteinyl-dopa, in the plasma of these same groups of patients with neurodegenerative disease and normal controls; no significant differences were identified. Serum concentrations of two other antioxidant substances, alpha-tocopherol and uric acid, were also statistically similar in these groups. In conclusion, analysis of several blood products relevant to oxidant stress, including malondialdehyde, 5-S-cysteinyl-dopa, alpha-tocopherol, and uric acid, failed to distinguish patients with Parkinson's disease or dementia of Alzheimer's type from controls.

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PubMed1995

The prevalence of dementia is changing over time in Rochester, Minnesota.

Resources of the Rochester Epidemiology Project were used to estimate prevalence rates for dementia on January 1, 1975, 1980, and 1985, and to evaluate trends over time. Prevalence rates increased with age for both men and women. There was no difference in the prevalence rates for January 1, 1975, and January 1, 1980, but there was a significant increase between January 1, 1980, and January 1, 1985. Similar results were found for Alzheimer's disease. Age was an important factor in the trend data. The apparent increase in prevalence over time is probably multifactorial.

Age Factors↗

PubMed1994

Incidence and prevalence of Huntington's disease in Olmsted County, Minnesota (1950 through 1989).

OBJECTIVE: To calculate average annual incidence rates for Huntington's disease (HD) from 1950 through 1989 and to estimate prevalence rates of the disease for January 1, 1960, and January 1, 1990. DESIGN: Health care records from all sources, including hospitals, outpatient clinics, and long-term care institutions, are readily available for all inhabitants of Olmsted County, Minnesota. The diagnoses entered in these records have been coded and indexed. All health care records containing a diagnosis that might suggest HD were reviewed, and those patients for whom the symptoms of HD began between January 1, 1950, and December 31, 1989, were identified. We used specific criteria for diagnosing HD. PARTICIPANTS: Health care records were reviewed; residence in Olmsted County during the year of symptom onset was required. MAIN OUTCOME MEASURES: Average annual incidence rates and prevalence rates for January 1, 1960, and January 1, 1990. RESULTS: Overall incidence rates were 0.4 (95% confidence interval [CI], 0.1 to 0.8) for women and 0.2 (95% CI, 0.04 to 0.6) for men per 100,000 person-years. Estimated prevalence rates for January 1, 1960, per 100,000 person-years were 6 (95% CI, 0.7 to 21.5) for women and 6.6 (95% CI, 0.8 to 23.8) for men. For January 1, 1990, the prevalence rates were 1.8 (95% CI, 0.04 to 10.2) for women and 2 (95% CI, 0.05 to 10.9) for men. CONCLUSIONS: Incidence and prevalence rates of HD in this community are similar to those reported in other communities. The small numbers of affected persons do not allow an estimate of variation over time.

Female↗

PubMed1994

Interaction between genetic and environmental risk factors for Alzheimer's disease: a reanalysis of case-control studies.

To study the interaction among genetic and environmental risk factors, a reanalysis of case-control studies of Alzheimer's disease (AD) was conducted based on the original data of all studies carried out to January 1, 1990. Seven studies were included in the present analysis, comprising a total of 814 AD patients and 894 control subjects. When comparing those with a positive and negative family history of dementia, similar odds ratio were found for late maternal age [1.7; 95% confidence interval (0.6-4.8) vs. 2.0 (1.1-3.5)], head trauma [1.7 (0.7-4.2) vs. 1.9 (1.1-3.2)], and history of depression [2.0 (0.2-19.8) vs. 2.1 (0.8-1.7)]. This suggests a model in which these risk factors increase the risk for AD independent of family history of dementia. Among those with a positive family history of dementia, the odds ratios for family history of Down's syndrome [4.2 (0.9-20.0)] and of Parkinson's disease [3.3 (0.4-28.2)] tended to be higher than among those with a negative family history of dementia [2.6 (0.8-8.5) and 2.4 (0.8-7.0), respectively]. However, for both disorders the difference in odds ratio was not statistically significant. For history of cigarette smoking, there was no association to AD for those with no first degree relatives with dementia and an inverse relation with AD for those with a positive family history. Although in all analyses, family history of dementia remained significantly associated with AD in the absence of other factors, the odds ratio associated with family history of dementia tended to be lower for those with a positive smoking history, particularly for those with two or more affected relatives. These findings suggest that smoking may interact specifically with a genetically determined process.

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