The accuracy of early diagnosis and predictors of death in Alzheimer's disease and vascular dementia--a follow-up study

Mortality in incident dementia - results from the German Study on Aging, Cognition, and Dementia in Primary Care Patients

OBJECTIVE

Dementia is known to increase mortality, but the relative loss of life years and contributing factors are not well established. Thus, we aimed to investigate mortality in incident dementia from disease onset.

METHOD

Data were derived from the prospective longitudinal German AgeCoDe study. We used proportional hazards models to assess the impact of sociodemographic and health characteristics on mortality after dementia onset, Kaplan-Meier method for median survival times.

RESULTS

Of 3214 subjects at risk, 523 (16.3%) developed incident dementia during a 9-year follow-up period. Median survival time after onset was 3.2 years (95% CI = 2.8-3.7) at a mean age of 85.0 (SD = 4.0) years (≥2.6 life years lost compared with the general German population). Survival was shorter in older age, males other dementias than Alzheimer's, and in the absence of subjective memory complaints (SMC).

CONCLUSION

Our findings emphasize that dementia substantially shortens life expectancy. Future studies should further investigate the potential impact of SMC on mortality in dementia.

[Impact of vascular pathology on survival times of 173 dementia patients--Hachinski's ischemic score as a predictive tool for clinical purposes]

Alzheimer's disease and vascular dementia still may be looked upon as distinct nosologic entities, representing the two main etiologic categories of senile dementia. However, rather recent findings suggest a comorbidity of neurodegenerative and ischemic pathology in a majority of dementia cases in later life. The effect of the vascular pathology on the survival time was studied in 173 dementia outpatients. For 147 patients with complete datasets, we were able to gain information concerning their survival time. As an indicator of cerebrovascular morbidity the 18-point ischemic scale of Hachinski (HIS) was correlated with the survival time. Thus, we did not use the HIS for its original purpose to differentiate between degenerative and vascular dementia, but to roughly evaluate the cerebrovascular impact in a continuum model. Using the Cox model we calculated mortality risks for every point on the HIS. We found a Cox hazard ratio of 1.038 for each supplementary point on the HIS, which equals a 3.8% higher relative mortality risk. The result misses significance (p=0.092), but indicates a clear tendency towards a shortening of survival time by vascular comorbidity. Future prospective studies should integrate brain imaging to further corroborate our findings.

Mediterranean diet and Alzheimer disease mortality

BACKGROUND

We previously reported that the Mediterranean diet (MeDi) is related to lower risk for Alzheimer disease (AD). Whether MeDi is associated with subsequent AD course and outcomes has not been investigated.

OBJECTIVES

To examine the association between MeDi and mortality in patients with AD.

METHODS

A total of 192 community-based individuals in New York who were diagnosed with AD were prospectively followed every 1.5 years. Adherence to the MeDi (0- to 9-point scale with higher scores indicating higher adherence) was the main predictor of mortality in Cox models that were adjusted for period of recruitment, age, gender, ethnicity, education, APOE genotype, caloric intake, smoking, and body mass index.

RESULTS

Eighty-five patients with AD (44%) died during the course of 4.4 (+/-3.6, 0.2 to 13.6) years of follow-up. In unadjusted models, higher adherence to MeDi was associated with lower mortality risk (for each additional MeDi point hazard ratio 0.79; 95% CI 0.69 to 0.91; p = 0.001). This result remained significant after controlling for all covariates (0.76; 0.65 to 0.89; p = 0.001). In adjusted models, as compared with AD patients at the lowest MeDi adherence tertile, those at the middle tertile had lower mortality risk (0.65; 0.38 to 1.09; 1.33 years' longer survival), whereas subjects at the highest tertile had an even lower risk (0.27; 0.10 to 0.69; 3.91 years' longer survival; p for trend = 0.003).

CONCLUSION

Adherence to the Mediterranean diet (MeDi) may affect not only risk for Alzheimer disease (AD) but also subsequent disease course: Higher adherence to the MeDi is associated with lower mortality in AD. The gradual reduction in mortality risk for higher MeDi adherence tertiles suggests a possible dose-response effect.

Incident dementia cases and mortality. Results of the leipzig Longitudinal Study of the Aged (LEILA75+)

Mortality caused by dementia has mainly been examined in population-based studies relying on prevalent cases. This study aims to investigate the impact of incident dementia on mortality as well as to identify factors influencing the course of dementia and those predicting early death in demented individuals. A representative community sample of 1,692 individuals aged 75 years and over was examined by neuropsychological testing in a four-wave study. Data were analyzed with the Cox proportional hazards model after making necessary adjustments for potential covariates. At the third follow-up 51% of the incident demented and 19% of the participants without dementia had died. The mean survival time was 3.1 years (95% CI = 2.8-3.4) for the demented subjects and 4.0 years (95% CI = 3.9-4.0) for those without dementia (p < 0.001). In the total sample, the relative risk of dying after developing dementia was estimated to be 2.4 (95% CI = 1.6-3.6) with age, sex, education, co-morbidity, and institutionalization being taken into consideration. Those persons with incident dementia who died had a more severe dementia. Population-based studies relying on incident cases are especially valuable in describing course and outcome of dementia. Studies relying on prevalent cases and clinical samples tend to overestimate mortality and propose course-modifying factors that are challenged by studies relying on incident cases.

Energy-containing nutritional supplements can affect usual energy intake postsupplementation in institutionalized seniors with probable Alzheimer's disease

OBJECTIVES

To determine whether increases in caloric intake associated with consumption of a mid-morning nutritional supplement for 3 weeks were maintained in the week after stopping the supplement and to investigate the effects of body mass index (BMI) and cognitive and behavioral measures on this response.

DESIGN

Secondary analysis of a previously published randomized, crossover, nonblinded clinical trial.

SETTING

A fully accredited geriatric care facility affiliated with the University of Toronto.

PARTICIPANTS

Thirty institutionalized seniors with probable Alzheimer's disease (AD) who ate independently.

MEASUREMENTS

Investigator-weighed food intake, body weight, cognitive (Severe Impairment Battery; Global Deterioration Scale) and behavioral (Neuropsychiatric Inventory--Nursing Home version; London Psychogeriatric Rating Scale) assessments.

RESULTS

Individuals who responded successfully to supplementation as indicated by increases in daily energy intake were likely to maintain 58.8% of that increase postsupplementation, although stopping the supplement was associated with decreased habitual energy intake in low-BMI individuals who reduced their daily intakes during supplementation in response to the extra calories. Cognitive/behavioral tests were not reliable predictors of postsupplement intake.

CONCLUSION

Institutionalized seniors with probable AD are likely to alter their usual energy intakes to maintain changes resulting from 3 weeks of supplementation. This effect may allow for rotating supplementation schedules in nursing homes that could reduce staff burden, but only for those individuals who are most likely to respond favorably. These data indicate that nutritional supplements and diet plans should be carefully prescribed in low-BMI individuals to limit variability in total energy provided and thus prevent lower-than-normal intake.

A randomized, crossover trial of high-carbohydrate foods in nursing home residents with Alzheimer's disease: associations among intervention response, body mass index, and behavioral and cognitive function

BACKGROUND

Despite recognition that weight loss is a problem in elderly persons with probable Alzheimer's disease (AD), increasing their food intake remains a challenge. To effectively enhance intake, interventions must work with individuals' changing needs and intake patterns. Previously, the authors reported greater food consumption at breakfast, a high-carbohydrate meal, compared with dinner, and shifts toward carbohydrate preference at dinner in those with increased behavioral difficulties, low body mass index, or both.

METHODS

Thirty-four nursing home residents with probable AD who ate independently participated in a randomized, crossover, nonblinded study of two nutrition interventions. The intervention described here included replacing 12 nonconsecutive "traditional" dinners with meals high in carbohydrate but comparable to traditional dinners in protein. Measures included weighed food intake, body weight, cognitive function (as assessed using the Severe Impairment Battery and Global Deterioration Scale), behavioral disturbances (as assessed using the Neuropsychiatric Inventory-Nursing Home Version), and behavioral function (as assessed using the London Psychogeriatric Rating Scale).

RESULTS

Group mean dinner and 24-hour energy intake increased during the intervention phase compared with baseline, protein intake was unaffected, and carbohydrate intake increased. Increased dinner intake, attributable to intervention foods, was achieved in 20 of 32 of participants who completed the study and was associated with increased carbohydrate preference, poorer memory, and increased aberrant motor behavior. Those with low body mass indices were the most resistant to the intervention.

CONCLUSIONS

Providing a high-carbohydrate meal for dinner increases food intake in seniors at later stages of the disease who are experiencing cognitive and behavioral difficulties, possibly as a result of a shift in preference for high-carbohydrate foods.

Providing nutrition supplements to institutionalized seniors with probable Alzheimer's disease is least beneficial to those with low body weight status

OBJECTIVES

To examine whether providing a midmorning nutrition supplement increases habitual energy intake in seniors with probable Alzheimer's disease (AD) and to investigate the effects of body weight status and cognitive and behavioral function on the response to the intervention.

DESIGN

Randomized, crossover, nonblinded clinical trial.

SETTING

A fully accredited geriatric teaching facility affiliated with the University of Toronto's Medical School with a home for the aged.

PARTICIPANTS

Thirty-four institutionalized seniors with probable AD who ate independently.

INTERVENTION

Nutrition supplements were provided between breakfast and lunch for 21 consecutive days and compared with 21 consecutive days of habitual intake.

MEASUREMENTS

Investigator-weighed food intake, body weight, cognitive function (Severe Impairment Battery and Global Deterioration Scale), behavioral disturbances (Neuropsychiatric Inventory-Nursing Home Version), and behavioral function (London Psychogeriatric Rating Scale).

RESULTS

Relative to habitual intake, group mean analyses showed increased 24-hour energy, protein, and carbohydrate intake during the supplement phase, but five of 31 subjects who finished all study phases completely compensated for the energy provided by the supplement by reducing lunch intake, and 24-hour energy intake was enhanced in only 21 of 31 subjects. Compensation at lunch was more likely in subjects with lower body mass indices, increased aberrant motor behavior, poorer attention, and increased mental disorganization/confusion.

CONCLUSION

Nutrition supplements were least likely to enhance habitual energy intake in subjects who would normally be targeted for nutrition intervention-those with low body weight status. Those likely to benefit include those with higher body mass indices, less aberrant motor problems, less mental disorganization, and increased attention.

Which factors influence cognitive decline in older adults suffering from dementing disorders?

BACKGROUND

Although extensive research has been done on dementing disorders in recent decades, their natural course and prognosis are not yet well understood. The aim of our study was to assess cognitive decline in a representative sample of demented elderly and to analyse the predictive value of a broad spectrum of sociodemographic, neurological and clinical variables.

METHODS

A random sample of elderly patients in primary care (n = 407) was drawn from a total of 3721 patients. The sample has been stratified according to the degree of cognitive impairment as assessed by their GPs. The patients were examined by means of a standardized research interview, including comprehensive cognitive testing (Hierarchic Dementia Scale) and the assessment of neurologic and physical impairments as well as of mental state (CAMDEX criteria). After a mean interval of 28 months, a follow-up study was conducted using essentially the same instruments.

RESULTS

At baseline, 117 of the 407 patients were identified as suffering from mild, moderate, or severe dementia. The two-year follow-up of those patients revealed high mortality rates (53/117). The surviving patients showed significant cognitive decline, although the rate varied considerably between individuals. The rate of progression was strongly related to the initial degree of severity, but also to the use of psychotropic medication, which was associated with a more rapid deterioration.

CONCLUSIONS

There are some prognostic indicators that can help to establish the prognosis for dementia patients. The best indicator for both--the rate of cognitive decline and the probability of survival--is the severity of dementia.

A multistate model of the genetic risk of Alzheimer's disease

The risk of Alzheimer's disease (AD) increases rapidly with age. It is not clear whether this increase continues at the very oldest ages. A slowing of the rate of increase in risk could result from heterogeneity associated with genetic or other risk factors. This study models explicitly the effect of heterogeneity of risk on the age pattern of incidence of AD. The model is fitted to published data from five prevalence studies and nine studies of AD risk by genotype for the apolipoprotein-E (APOE) gene. The model suggests that the prevalence of AD among white males at age 100 is 41.5%. Heterogeneity in the risk of AD causes the incidence rate to level off at about 11.7% per year at age 102. Some of the heterogeneity of risk is due to differences by APOE genotype. The model estimates that at age 80, the epsilon3/4 genotype is associated with an incidence rate 3.40 times that of those with the epsilon3/3 genotype. The epsilon4/4 genotype is associated with a relative risk of 9.4. Carriers of the epsilon2 allele have a risk that is only 43% of the risk among the epsilon3/3. There is substantial variation in risk associated with unobserved risk factors. Within each APOE genotype, the coefficient of variation of risk is about 1.09. In addition, the model estimates that about 0.20% of the population carries genes that cause AD at very early ages, through mechanisms that are not associated with the APOE genotype.

Shift in diurnal feeding patterns in nursing home residents with Alzheimer's disease

BACKGROUND

Individuals with Alzheimer's disease (AD) are highly susceptible to weight loss and malnutrition, which, to date, have not been associated with decreased food consumption. The current study examined food intake patterns and how they change in relation to body mass index (BMI), behavioral function, and cognitive status in institutionalized seniors with AD.

METHODS

Twenty-one consecutive days of investigator-weighed food intake collections were conducted on 25 subjects with likely AD residing at a home for the aged. All subjects maintained the ability to self-feed.

RESULTS

Eighty-eight percent of participants did not meet targeted energy needs, including an estimated 37% prevalence of protein inadequacy. Subjects with increased behavioral difficulties, based on the London Psychogeriatric Rating Scale, had reduced meal-related intakes that were highly associated with decreased energy consumption at dinner. With behavioral changes, particularly increased mental disorganization and confusion, there was a shift in circadian eating patterns such that the greatest proportion of daily energy was consumed at breakfast. Individuals with low BMIs tended to be those with more behavioral difficulties, such that BMI was also associated with the shift in overall eating patterns.

CONCLUSIONS

Changes in behavioral function in seniors with AD result in a circadian shift in intake patterns with the preponderance of calories consumed at breakfast in those with increased behavioral difficulties. This shift in eating patterns associates both with poor overall intake and poor BMI.

Meal delivery practices do not meet needs of Alzheimer patients with increased cognitive and behavioral difficulties in a long-term care facility

BACKGROUND

Alterations in circadian rhythms and behavioral difficulties likely impact meal consumption patterns in elderly individuals with probable Alzheimer's disease (AD). Despite these known changes, the profile of meals provided in the institution parallels the needs of younger, free-living, healthy populations. This investigation examined the impact of food delivery patterns on achieved intakes in elderly individuals with probable AD in a long-term care facility and how this relationship changes depending on time of day, body weight status, behavioral function, and cognitive ability.

METHODS

Twenty-one consecutive days of investigator-weighed food intake and delivery collections were conducted on 25 elderly individuals with probable AD who maintained the ability to self-feed.

RESULTS

Energy consumed was positively associated with energy delivered for the majority of subjects, although the strength of this relationship varied across subjects and throughout the day. Energy delivered had the greatest impact on energy consumed at breakfast and the least impact at dinner in those with the greatest behavioral difficulties and cognitive impairment. Although those with low body mass indexes (BMIs) were likely to be delivered more energy, the impact of delivery on intakes decreased as energy delivered increased.

CONCLUSIONS

Delivering excess energy to patients with poor BMIs likely does not result in increased energy consumption. Behavioral and cognitive deterioration leads to a shift in the time of day that energy delivered has an impact on energy consumption, with the most progressed individuals being most impacted by foods delivered in the morning, suggesting that traditional meal practices are inappropriate for elderly individuals with AD.

Factors associated with mortality in patients with early-onset Alzheimer's disease: a five-year longitudinal study

To identify neuropsychiatric and somatic factors related to survival in early-onset Alzheimer's disease, we longitudinally studied 108 patients (35 male, 73 female) with early-onset Alzheimer's disease who were 46 to 64 years old at onset and 50 to 69 years old when diagnosed at our institution. A five-year follow-up, 30 patients had died. Pneumonia was the most common cause (73%), followed by malignancy (20%) and heart disease (7%). Kaplan-Meier survival curves showed a lower survival rate in patients with early-onset Alzheimer's disease than in age- and sex-matched life-table data in Japan. In Cox proportional hazards analysis, male gender, early disease onset, concurrent physical illness at time of diagnosis, and a low mini-mental state examination score increased the likelihood of death in patients with early-onset Alzheimer's disease. Our study confirmed that these patients have considerable excess mortality and a different pattern of cause of death than in the general population. Gender, age at onset, physical illness, and cognitive function strongly influenced survival. These factors may be predictors of mortality in patients with early-onset Alzheimer's disease that are useful in counseling patients and their families.

Functional status and clinical correlates in cognitively impaired community-living older people

We describe the prevalence of cognitive impairment in a population of community-living older people, its association with functional decline, and degree of comorbidity. In addition, we examined the relationship between different levels of cognitive impairment and mortality. We conducted an observational study of 1787 patients aged 65 years and above with any degree of cognitive impairment. Patient data were collected with the Minimum Data Set for Home Care. More than 50% of patients had some level of cognitive impairment, which correlates with the degree of physical frailty. On the contrary, patients with cognitive impairment appear to have fewer comorbid conditions and are less likely to receive medications than patients with normal cognitive status. In particular, hypertension, congestive heart failure, chronic obstructive pulmonary disease, cancer, diabetes mellitus, and osteoporosis are found more frequently among patients with normal mental status compared with those showing some level of cognitive defects. Yet, more severe cognitive impairment is associated with a higher mortality rate. Demented patients are characterized by a high prevalence of functional disability and by increased mortality. This increased morbidity and mortality rate is associated with a lower prevalence of comorbid clinical conditions and drug use, relative to patients with normal cognitive performance. The present findings support the possibility that severe cognitive impairment has an independent effect on survival.

Predictors of mortality among demented elderly in primary care

OBJECTIVES

To evaluate a wide range of sociodemographic, neurological and clinical variables as to whether they predict mortality in a representative sample of demented elderly.

DESIGN

A three-stage community survey was conducted, based on a total of 3721 elderly patients whose cognitive status was assessed by their general practitioners (stage I). A stratified random sample of patients underwent a standardized research interview, including cognitive testing and the assessment of mental status, physical illness, sensory impairment and motor disability (stage II). After a mean interval of 28 months, all patients were recontacted. For deceased patients a close reference person was interviewed and the exact date of death was recorded (stage III). The influence of the predictor variables on mortality was determined by using the Cox proportional hazards model.

SUBJECTS

A stratified random sample of 117 patients in primary care (mean age 82 years) suffering from mild, moderate or severe dementia (Alzheimer type, vascular or mixed dementia).

MATERIALS

Hierarchical Dementia Scale (HDS), a modified version of the Hamilton Depression Scale, other clinical rating scales and CAMDEX criteria for clinical diagnosis and a degree of severity of dementia.

RESULTS

Fifty-three of the 117 demented patients had died during the follow-up interval. The mortality risk increased steeply with the degree of severity of dementia. By controlling for this variable, only age and motor disability contributed significantly to the prediction of mortality, whereas gender, social class, type of dementia, extrapyramidal signs and other clinical features showed no or only a weak effect on the outcome.

CONCLUSION

The remaining life expectancy of the demented elderly depends primarily on the severity of the dementia, the patients' age and their general physical health. The influence of other clinical features which often have been hypothesized as indicators of specific subgroups of dementia was mainly due to their relationship to the disease severity.

Predictors of mortality in patients with Alzheimer's disease living in nursing homes

OBJECTIVES

To identify factors associated with mortality in patients with Alzheimer's disease, and to evaluate whether these factors vary according to severity of cognitive impairment.

METHODS

Data were from the SAGE database which includes information on all residents admitted between 1992 and 1995 to all Medicare/ Medicaid certified nursing homes of five US states. We conducted a longitudinal follow up study (median 23 months) on 9264 patients aged 65 years and above with a diagnosis of Alzheimer's disease. Patient data including demographic characteristics, dementia severity, comorbidity, and other clinical and treatment variables were collected with the Minimum Data Set. Information on death was derived through linkage to Medicare files. Baseline characteristics were used to predict survival in univariate and multivariate Cox proportional hazard models.

RESULTS

Overall mortality rate was 50%, with a first year rate of 25.7%. Increased age (risk ratio (RR) 1. 83; 95% confidence interval (95% CI) 1.65-2.03, for patients 85+ years), male sex (RR 1.81; 95% CI 1.70-1.94), limitation in physical function (RR 1.45; 95% CI 1.27-1.66), a condition of malnutrition (RR 1.31; 95%CI 1.23-1.39), the presence of pressure ulcers (RR 1.24; 95% CI 1.13-1.36), a diagnosis of diabetes mellitus (RR 1.32; 95% CI 1.21-1.43), and of cardiovascular diseases (RR 1.22; 95% CI 1. 14-1.30) were independent predictors of death, regardless of the severity of baseline dementia. Sensory problems (hearing and vision) and urinary incontinence were associated with increased mortality only among patients with less severe dementia. The presence of disruptive behaviour, aphasia, and a diagnosis of Parkinson's disease were not related to survival. African-Americans and other minority groups were less likely to die relative to white people.

CONCLUSIONS

Age, sex, functional limitation, and malnutrition seem to be the strongest predictors of death for patients with Alzheimer's disease in nursing homes. Altogether, severity of dementia has no influence on survival, yet the predictive role of certain variables depends on the degree of impairment. Minority groups have a reduced risk of death relative to white people.

Dementia is a major predictor of death among the Italian elderly. ILSA Working Group. Italian Longitudinal Study on Aging

BACKGROUND

Neurologic diseases are rarely listed on death certificates because death is more often attributed to cardiovascular and pneumonic events occurring during terminal stages.

OBJECTIVE

To evaluate the effect of major age-associated neurologic and non-neurologic diseases on survival in a cohort of Italian elderly.

METHODS

A population-based multicenter survey, carried out in eight Italian municipalities, with a sample of 5,632 individuals aged 65 to 84 years. The entire sample was screened for all the diseases under study, and all individuals were interviewed about risk factors. Those who screened positive underwent clinical assessments by specialists. Two years after the baseline survey, the study population was followed up to determine the vital status either directly from the individuals or from proxy respondents. A copy of the death certificate was obtained for each individual who had died. The risk of dying (mortality risk ratio [MRR]) was calculated using the Cox proportional hazards model in which we included all the diseases under study, age, gender, and years of education.

RESULTS

At follow-up (mean duration 26.7 +/- 5.4 months) 444 individuals had died. The Cox proportional hazards model selected the following as significant predictors of death: age (for year of age MRR = 1.12; 95% confidence interval [CI], 1.08 to 1.15), male gender (MRR = 1.72; 95% CI, 1.27 to 2.34), institutionalization (MRR = 4.17; 95% CI, 2.20 to 7.94), dementia (MRR = 3.61; 95% CI, 2.55 to 5.11), neoplasm (MRR = 2.01; 95% CI, 1.20 to 3.38), heart failure (MRR = 1.87; 95% CI, 1.27 to 2.76), and diabetes (MRR = 1.62; 95% CI, 1.12 to 2.34).

CONCLUSIONS

These data provide further evidence on the malignancy of dementia, which proved the major predictor of death in the elderly, with an MRR higher than neoplastic diseases and other severe age-associated conditions.

Deaths attributable to Alzheimer's disease in the United States

OBJECTIVES

This study provided 2 estimates of the number of deaths attributable to Alzheimer's disease in the United States.

METHODS

One estimate was based on data from the East Boston, Mass, study. The second was based on a simulation using population-based estimates of prevalence and separate estimates of excess death by duration of disease.

RESULTS

Despite different methods and very different estimates of prevalence, these 2 methods led to very similar estimates of 173,000 and 163,000 excess deaths.

CONCLUSIONS

These estimates suggest that 7.1% of all deaths in the United States in 1995 are attributable to Alzheimer's disease, placing it on a par with cerebrovascular diseases as the third leading cause of death.

Natural history of Alzheimer's disease and other dementias: review of the literature in the light of the findings from the Kungsholmen Project

The elderly population is increasing more than any other sector of the population. Dementia, a prevalent condition in the elderly, increases disability, morbidity and mortality among older people. For these reasons the possibility of predicting progression and prognosis has enormous importance. Despite the fact that dementia has gained widespread recognition in the past few decades, the knowledge of its natural history, in terms of progression and prognosis are not yet completely understood. However, thanks to longitudinal research, which has only recently begun to proliferate, not only is better comprehension of the continuity of the cognitive decline possible, but also the identification of some prognostic factors.

Aging and cerebrovascular disease

Aging influences cerebrovascular disease expression by a variety of mechanisms. Age-related changes in cerebral autoregulation, cellular metabolism, the blood-brain barrier, and autonomic function may leave the cerebrovascular system vulnerable to injury. Certain cerebrovascular disease, such as atrial fibrillation, watershed infarctions, carotid artery atherosclerosis, cerebral hemorrhages, subdural hematomas, and transient global amnesia manifest in the elderly. Vascular dementia and white matter disease are better understood with newer neuroimaging studies, careful neuropsychological and histopathologic examinations. Atherosclerosis and cerebral amyloid angiopathy may have larger roles than previously understood in Alzheimer's disease.

Prognostic factors in very old demented adults: a seven-year follow-up from a population-based survey in Stockholm

OBJECTIVE

To detect prognostic factors in very old demented subjects with Alzheimer's disease (AD), vascular dementia (VaD), and other types of dementia (OD).

DESIGN

Follow-up clinical examinations of dementia patients from a population-based study after 3- and 7-year intervals.

SETTING AND PARTICIPANTS

In an established population aged 75 years and older in Stockholm, Sweden, there were 133 cases of AD, 52 of VaD, and 38 of OD.

MAIN OUTCOME MEASURES

Predictors of survival at 3- and 7-year follow-up examinations were evaluated by Cox proportional hazard models. Progression was measured as the annual rate of change in Mini-Mental State Examination (MMSE) scores. Linear models were used to evaluate predictors of progression.

RESULTS

Older age, male gender, low education, comorbidity, and functional disability predicted shorter 7-year survival in the 223 prevalent dementia cases. Other factors, including type of dementia, dementia severity, and duration of the disease were not significant. The average rate of cognitive decline in the 81 mild to moderate demented subjects who survived 3 years was 2.4 MMSE points per year. Type of dementia (AD vs OD), higher baseline cognitive function, and greater functional disability predicted faster decline. Despite similar survival probability, predictors of death varied as a function of dementia type: Older age (for AD and VaD), comorbidity (for AD and OD), and functional dependency (for VaD). In AD, prognostic factors were similar to those described for the combined dementia groups, with the exception of an accelerated cognitive decline among women.

CONCLUSIONS

Although methodological difficulties exist, it is possible to identify demented subjects with worse prognoses (shorter survival and faster cognitive decline) by using clinical and demographic data. Clinicians and healthcare planners should be aware of the potential usefulness of functional dependence as a prognostic indicator. Finally, the need for careful clinical examinations of demented subjects is stressed by the increased mortality found among those demented who are also affected by other chronic conditions.

Dementia as a predictor of adverse outcomes following stroke: an evaluation of diagnostic methods

BACKGROUND AND PURPOSE

Although it is understood that dementia is a risk factor for adverse outcomes, little is known about the predictive validity of the numerous methods that have been proposed for its diagnosis. Thus, we performed the present study to assess the utility of a variety of diagnostic methods in the prediction of adverse outcomes following stroke.

METHODS

We administered neuropsychological, neurological, and functional examinations to 244 patients (age, 71.7+/-8.5 years) 3 months after ischemic stroke. We diagnosed dementia using each of the following methods: (1) neuropsychological testing, requiring deficits in increasing numbers of cognitive domains, both with and without memory impairment, as well as functional impairment; (2) Mini-Mental State Examination (MMSE) score of <24; and (3) neurologists' clinical judgment. We then used survival analyses to investigate the ability of diagnoses based on those methods to predict death and recurrent stroke during long-term follow-up.

RESULTS

Log-rank tests and Cox proportional hazards analyses, with recurrent stroke entered as a time dependent covariate, determined that all of the paradigms were significant predictors of mortality, but the performance of paradigms based on neuropsychological testing was superior to the use of the MMSE and clinical judgment, particularly when memory impairment was required. Log-rank tests determined that paradigms based on neuropsychological testing were the only significant predictors of recurrent stroke and performed best when memory impairment was required.

CONCLUSIONS

Our results suggest that dementia diagnosis based on neuropsychological assessment and an operationalized paradigm requiring deficits in memory and other cognitive domains is superior to other conventional methods in its ability to identify patients at elevated risk of adverse outcomes following stroke.

Natural history of Alzheimer's disease: prognostic value of plateaux

The aim of this 7-year inception cohort study was to determine the prognostic value of plateaux in cognitive decline in the course of Alzheimer's disease (AD) as well as their impact on the rate of progression of cognitive impairment. From a consecutive sample of 106 outpatients participating in a longitudinal study on AD, we selected 31 with a mild degree of mental deficit at presentation and a disease duration of at least 3 years when included into the study. All underwent extensive clinico-neuropsychological testing about every 6 months and there were no drop-outs. Mean period of follow-up lasted 6.8 (SD 2.9) years. Nineteen patients displayed a plateau, where a plateau refers to a patient's remaining on a mild level of cognitive decline for more than two years. Survival curves (Kaplan-Meier method) showed that patients with plateaux reached several end-points--very severe functional or cognitive impairment, urinary incontinence, death--significantly later than patients without (p < 0.04). Patients with plateaux showed a smaller cognitive loss (p < 0.01) in terms of the mean annual rate of progression of mental decline. In conclusion plateaux in an early stage of Alzheimer's Disease served to identify patients with a more favourable course.

Clinical assessment of mental decline in elderly people: a proposal for a new quantitative index

Despite the many instruments available for assessing elderly people, there is a need for additional methods to measure mental decline that would also be applicable in cross sectional and longitudinal studies. With this purpose in mind, our group developed and checked a new instrument, the Index of Mental Decline (IMD), which consists of five clusters of items intended for the assessment of cognition, personal interrelationships, affective disorders, apathy and somatic complaints. To improve its consistency, all clusters and items were evaluated individually, according to their clinical impact. Three levels of symptom importance were determined: absent to very mild, mild to moderate, severe to very severe. Inter-rater reliability and test-retest reliability were demonstrated in a sample of 59 subjects, and proved to be satisfactory. The validity of the IMD was tested in a group of 203 patients, in whom a clinical diagnosis of probable dementia (DSM III-R criteria) had been formulated. The results suggest the effectiveness of the IMD both in quantifying mental decline and monitoring clinical symptoms. The IMD cannot be the first step of diagnostic procedure, but it can be useful for evaluating mental decline in elderly subjects with cognitive disorders. In longitudinal studies, the presence of the same caregiver or informant is compulsory.