Showing papers by "Giovanni B. Frisoni published in 2003"

Computer-assisted imaging to assess brain structure in healthy and diseased brains

Abstract: Neuroanatomical structures may be profoundly or subtly affected by the interplay of genetic and environmental factors, age, and disease. Such effects are particularly true in healthy ageing individuals and in those who have neurodegenerative diseases. The ability to use imaging to identify structural brain changes associated with different neurodegenerative disease states would be useful for diagnosis and treatment. However, early in the progression of such diseases, neuroanatomical changes may be too mild, diffuse, or topologically complex to be detected by simple visual inspection or manually traced measurements of regions of interest. Computerised methods are being developed that can capture the extraordinary morphological variability of the human brain. These methods use mathematical models sensitive to subtle changes in the size, position, shape, and tissue characteristics of brain structures affected by neurodegenerative diseases. Neuroanatomical features can be compared within and between groups of individuals, taking into account age, sex, genetic background, and disease state, to assess the structural basis of normality and disease. In this review, we describe the strengths and limitations of algorithms of existing computer-assisted tools at the most advanced stage of development, together with available and foreseeable evidence of their usefulness at the clinical and research level.

An electronic memory aid to support prospective memory in patients in the early stages of Alzheimer's disease: A pilot study

Abstract: The use of an electronic memory aid (EMA) for patients with mild-to-moderate probable Alzheimer disease is examined in five outpatients aged 58-79 years. The ability to remember to carry out seven tasks at a particular time was evaluated in three experimental conditions: recall without an external memory aid, recall with a written list and recall with support available from an EMA. The use of an EMA significantly improved patients' prospective memory, while the written list and free recall were not useful. Future research that examines the value of using an EMA to help with tasks that are associated with prospective memory with a larger sample of patients within their own home context is suggested.

Neuroimaging tools to rate regional atrophy, subcortical cerebrovascular disease, and regional cerebral blood flow and metabolism: consensus paper of the EADC.

Abstract: Neuroimaging is a mainstay in the differential diagnosis of patients with cognitive impairment. The often equivocal clinical pictures, the prognostic uncertainty of the earliest stages of mild cognitive impairment, and the subtle brain changes mean that neuroimaging techniques are of potentially great incremental diagnostic value. A number of methods, ranging from very simple subjective visual ratings to highly sophisticated computerised tools, have been developed, which allow rating of structural and functional brain changes. The choice of the method is not obvious, and current guidelines provide no indications on which tools should be preferred. In this paper, we give indications for tools with demonstrated accuracy for detecting regional atrophy, cerebrovascular disease, and regional brain function, and discuss these according to increasing technological complexity, ranging from those with high feasibility that can be used at the patient's bedside to highly technological ones that require trained personnel and specific hardware and software.

Mild Cognitive Deterioration with Subcortical Features: Prevalence, Clinical Characteristics, and Association with Cardiovascular Risk Factors in Community‐Dwelling Older Persons (The InCHIANTI Study)

Abstract: OBJECTIVES: To identify subjects with minimal or mild nonamnestic cognitive impairment with parkinsonian stance and gait and investigate vascular correlates of this condition. DESIGN: First wave of an epidemiological longitudinal study (InCHIANTI) on factors predicting loss of mobility in older persons. SETTING: The Chianti geographic area (Tuscany, Italy). PARTICIPANTS: Five hundred fifty-six subjects aged 70 to 90 with Mini-Mental State Examination (MMSE) scores greater than 23 of 30, of the 1,260 persons aged 65 and older randomly selected from the population registry of Greve in Chianti and Bagno a Ripoli, two small towns near Florence. METHODS: Low cognitive performance (LCP) was defined as an age- and education-adjusted MMSE below the 50th percentile for the InCHIANTI population. Subcortical features were plastic rigidity on neurological examination (parkinsonism), gait disturbance (small-step gait or parkinsonian gait), and dysexecutive features. Two hundred forty-three participants had high cognitive performance, 166 had LCP without subcortical features, and 75 had LCP with subcortical features. Vascular risk factors were hypertension, atrial fibrillation or pathological findings on electrocardiogram (ECG), low serum high-density lipoprotein (HDL) or high low-density lipoprotein cholesterol, diabetes mellitus, obesity, and heavy smoking. RESULTS: Three main vascular risk factors were significantly more prevalent in LCP with subcortical features: hypertension (P = .02), atrial fibrillation or ECG changes (P = .04), and low HDL cholesterol (P = .001). LCP with subcortical features was significantly associated with cerebrovascular risk factors (P = .001). CONCLUSION: Gait disturbance and nonamnestic cognitive symptoms might be the consequence of subcortical vascular damage.

Drug treatment of REM sleep behavior disorders in dementia with Lewy bodies.

Abstract: Background: Dementia with Lewy bodies (DLB) is often associated with REM sleep behavior disorders (RBD) characterized, in contrast to the usual paralysis of REM sleep, by violent motor and verbal activity. Patients and Methods: The pharmacological management of RBD was investigated in three DLB patients treated with clonazepam, a benzodiazepine used as an antiepileptic, or donepezil, a cholinesterase inhibitor. Results: All three patients had marked improvement. The pharmacodynamic mechanisms underlying the efficacy of the two drugs might be due to facilitator effect on the pedunculopontine nucleus, a key structure in the physiology of REM sleep.

Atypical dementia associated with a novel presenilin-2 mutation.

Abstract: We describe an Italian pedigree with hereditary dementia associated with a novel T122R mutation in the presenilin-2 gene (PSEN2). The clinical history, symptom presentation, and structural neuroimaging were consistent with an atypical form of dementia. Disease expression varied within family members. One in a pair of mutated monozygotic twins had evident signs of disease, whereas the other did not, even if her functional neuroimaging investigations, cerebrospinal fluid levels of Aβ1-42, and Tau protein were able to provide markers for future disease development. These observations suggest the importance of still unknown biological and perhaps environmental factors in the disease determination.

Validation study of a CT-based weighted rating scale for subcortical ischemic vascular disease in patients with mild cognitive deterioration.

Abstract: Objectives: Subcortical ischemic vascular disease (SIVD) is frequently associated with cognitive impairment. Rating scales to grade cerebrovascular disease are available, but their

Prescription practices of diagnostic imaging in dementia: a survey of 47 Alzheimer's Centres in Northern Italy.

Abstract: Background To date, there are no data at the national or European level on the prescription practices of imaging (CT, MR, and SPET) in the diagnosis of cognitively impaired elderly patients. Methods We addressed prescription practices of diagnostic imaging in 47 Alzheimer's Centres in Northern Italy, with an ad-hoc questionnaire. Results The use of imaging in new cases was relatively intensive: 62% of the Alzheimer's Centres prescribed CT to more than 95% of cases, 24% prescribed MR to more than 33% of cases, and 33% prescribed SPET to more than 5% of cases. A minority of Alzheimer's Centres (n = 3, 6%) prescribed imaging to less than 100% of new cases. The association between onsite scanner availability and frequency of prescription increased from CT (Odds ratio (OR) = 1.8) through MR (OR = 2.4) to SPET (OR = 4.6), although only the latter was significant (95% confidence interval (CI) 1.2–17.7, p = 0.003). Patient-related factors (age, severity of cognitive impairment, and clinical suspicion of cerebrovascular disease) influenced prescription of structural imaging in 30–53% of Alzheimer's Centres and organizational factors (onsite scanner availability, and waiting list) in a similar proportion (32 and 43% respectively). Conclusions Organizational factors play a relevant role in the prescription of imaging exams in patients with cognitive impairment and, at least for CT, the perceived diagnostic added value is rather low, suggesting a high degree of uncertainty in the clinical use of imaging techniques. Copyright © 2003 John Wiley & Sons, Ltd.

Cognitive impairment modulates the effect of depressive symptoms on mortality in elderly people.

Abstract: To the Editor: The recent debate on the prognostic negative effect of depression on mortality (1,2) has been significantly enriched by Mehta and colleagues’ article on the association between depression and cognitive impairment and mortality in older adults (3). The authors conclude that cognitive function and depressive symptoms can be used together to stratify elderly adults into groups that have significantly different rates of death; moreover these two risk factors are associated in a progressive, additive manner. We would like to discuss this topic and present data of a study in an aging community-based population in Italy. The data were obtained in a multidimensional study carried out in a community-dwelling population aged 70 years and older living in the rural city of Ospitaletto, Brescia, Northern Italy (4). Of a total of 613, more than 70 elderly persons were recorded in the local registry office, 37 refused to participate, and 27 were contacted but did not complete the interview. There were 549 valid questionnaires available (89.6% of the eligible population). The data were collected at participants’ homes by trained community researchers. In addition to demographics (gender, age, years of education), mood was assessed with the short version of the Geriatric Depression Scale (GDS) (5), cognitive performance with the Mini-Mental State Examination (MMSE) (6), physical health as the number of chronic conditions, and disability by Katz’s activities of daily living (ADL) scale (7). Twentyfive participants with an MMSE score lower than 14 were excluded from the study, since, at a lower score, it is difficult to correctly detect depressive symptoms in a community survey, leaving 524 for further analysis. Cognitive impairment was defined as an MMSE score between 14 and 23, depression as a GDS score higher than 5, and disability as 1 or more ADL functions lost. Cox proportional hazards models were used to control for potentially confounding variables. The mean age of the 524 elderly participants (173 males and 351 females) was 76.66 5.1 years. They had 4.66 1.9 years of education, and were affected by 3.5 6 2.2 chronic conditions; 134 (24.4%) lived alone and 149 (27.1%) had 1 or more ADL functions lost. MMSE and GDS mean scores were 25.8 6 3.6 and 3.76 3.0, respectively. Patients were divided into 4 mutually exclusive groups based on the presence of neither, either, or both cognitive impairment and functional disability (see Table 1). Vital status was assessed for each participant 60 months from the baseline analysis. One hundred twenty-nine persons (24.6%) died during the follow-up period. Table 1 shows the association of depression with 60month mortality in the four groups of elderly participants, indicating an independent association between depressive symptoms and mortality in group A (‘‘physically healthy’’) and in group C (‘‘disabled, noncognitively impaired’’) (relative risks of 2.1 and 3.2, respectively). The association was not found in group B (‘‘cognitively impaired, nondisabled’’) and in group D (‘‘cognitively impaired and disabled’’). In the same population, we have previously demonstrated the independent association between cognitive impairment and depression with mortality (8,9). Data observed in this analysis show that the effect of depression on mortality is modulated by cognitive function. In fact, at variance with the data of Mehta and colleagues, our data suggest that, in a population of cognitively impaired participants, depressive symptoms do not exert any effect on mortality. Cognitive impairment may protect from the effect of depression onmortality since it reduces the insight of patients, an important mechanism mediating the consequences of mood disorders on physical health. Another explanation may rely on the fact that, in cognitively impaired patients,