Semantic priming for coordinate distant concepts in Alzheimer's disease patients.

Semantic priming paradigms have been used to investigate semantic knowledge in patients with Alzheimer's disease (AD). While priming effects produced by prime-target pairs with associative relatedness reflect processes at both lexical and semantic levels, priming effects produced by words that are semantically related but not associated should reflect only semantic activation processes. This study was aimed at further investigating automatic semantic priming effects in AD patients when semantically related concepts with little to no lexical association are used. Twenty patients with mild to moderate AD and 20 matched controls (NCs) performed a lexical decision task on 30 concept pairs (15 in the living and 15 in the non-living domain) in an automatic semantic priming paradigm. In order to investigate the relationship between priming alteration and semantic damage, we chose concepts from a database. This allowed us to quantify semantic indexes relative to the structural representation at the feature level. No priming was found in NCs or mild AD patients, probably because feature similarity was insufficient in the concept pairs used. Similar to the hyperpriming observed in previous studies, the appearance of priming in the moderate AD group suggests early semantic damage in which attribute knowledge is partially affected. Furthermore, the finding that priming was predicted by the level of sharing (in the semantic system) of features common to the two concepts in the pairs indicates that the level of redundancy of attribute information is the main factor responsible for resiliency to neurological damage in AD.

Correlation between cognitive impairment and the Rey auditory-verbal learning test in a population with Alzheimer disease.

Patients affected by Alzheimer disease (AD) need an accurate diagnosis, to the extent allowing us to find the best therapy or polytherapy, in order to take under control their cognitive impairment. In our Alzheimer Evaluation Units (from the Italian name abbreviated: UVA), the patients undergo a multidimensional evaluation, which can address us towards a proper diagnosis and of other weakening, or even dementia-related diseases. The patients are also subject to neuropsychometric and neuropsychological evaluations, allowing a more focused analysis on cognitive impairments. Among the tests, we use the Rey auditory-verbal learning test (RAVLT), evaluating the patient's verbal memory. A list of 15 words is read to each patient. N the first part of the test, the clinician repeats 5 times such a list. the patient is hen asked, at the end of every repetition, to tell all words he/she remembers. This part is useful to evaluate the immediate recall (IR) ability. The score, i.e., the total number of recalled words, ranges from 0 to 75. After 15 minutes, the delayed recall (DR) ability is evaluated: the patient is newly asked to repeat as many words as he can recall from the list. The score for this part ranges from 0 to 15 minutes. The score is corrected of rage and education, with a cut-off of 28.5 for IR and 4.7 for DR. We made a survey with the purpose of deciding if there was a correlation between cognitive impairment and verbal memory lack, whose deficiency appears earlier in AD. To this aim, we selected several patients with AD, diagnosed during the period between September 2002 and February 2003. We only considered those patients whose AD was not associated with other weakening diseases, and whose clinical dementia rating scale (CDR) score was between 0.5-2.0. A sample of 35 individuals (11 men and 24 women) could be obtained. A meaningful correlation was observed between CDR and IR (r = -0.725, p < 0.01), as well as between CDR and DR (r = -0.470; p < 0.05). Such a result confirms the importance of evaluating immediate and long-term memories, for the early diagnosis of AD, because it is the only symptom of clinically not yet diagnosed dementia, as proven also by other studies.

Behavioral disturbances in Alzheimer's disease: a non-pharmacological therapeutic approach.

Behavioral disturbances in patients with dementia are among the primary causes of institutionalization. Although the majority of authors agree that such symptoms are well controlled with non-pharmacological support, almost all studies have been focused on symptomatic drug therapy (typical or atypical neuroleptics). The aim of our study was to evaluate the reduction of psychiatric symptoms revealed with the test called empirical behavioral pathology in Alzheimer disease (E-Behave-AD) in a population of patients with AD whose caregivers underwent training to learn various communication strategies to utilize with family members. We evaluated 35 patients with AD (18 males, 17 females, average age 76.5 +/- 5.9 years). Of these patients, 18 (9 males, 9 females, average age 75.1 +/- 6.5 years) were relatives of caregivers who underwent training for six months, four group meetings and two individual ones. During the training, caregivers learned about the possibility of communication with persons with AD. They were taught how to interact with the AD patients in various phases of the illness and how to utilize effectively both verbal and non-verbal language. Other 17 patients (9 males, 8 females, average age 76.1 +/- 4.9 years) were followed as a control group. During the period of observation, all patients were given rivastigmine or donezepil. The two groups were homogenous for age, sex, antipsychotic drug therapy, and initial scores on mini-mental state examination (MMSE), activity of daily living (ADL), instrumental activity of daily living (IADL), and E-Behave-AD. After six months, we evaluated the patients with an analogous battery of tests. The analysis of data proceeded from the verification of homogeneity of test subjects and of the control group with t-test for non-paired data. We used the chi2 statistics to compare the qualitative variables between test subjects and the control group. For all statistical tests, a p < 0.05 was considered significant. In the group of patients with caregivers who underwent training, a statistically significant decrease in the E-Behave-AD score (p < 0.001) was observed after six months (7.7 vs. 10.5; p < 0.001). There was no statistically significant modification in the scores for the ADL, IADL, and MMSE (ADL 4.7 vs. 4.3, p = 0.09; IADL 3.2 vs. 3.1, p =0.4; MMSE 17.3 vs. 15.1, p = 0.1). Numerous evidences in literature underline the centrality of the language deficit in dementia, particularly in AD. A re-establishment, even if partial, of the channels of communication between AD patients and doctors, as well as between patients and caregivers, can reduce the frequency and intensity of behavioral disturbances in persons with AD.

The management of psychogeriatric patient.

The exponential growth in the prevalence of cognitive impairment of old patients leads the physicians to deal with a larger incidence of behavioral disorders (such as excitement,aggressiveness), and psychotic symptoms (such as delirium and visual hallucinations). The presence of psychotic troubles in dementia causes a remarkable distress to caregivers and involves higher difficulties in the patient management. The estimates of such troubles range between 15 and 75 %. Geriatric assessment and the management of behavioral troubles require a prompt evaluation of all their possible causes. As a matter of fact, their appearance often reveals a physical disturbance (pain, fever, etc.), or adverse environmental conditions, or it could also be a consequence of a multiple drug therapy. For this reason,the use of antipsychotics should always be preceded by an accurate clinical diagnosis.Anxiolytic, anti-depressive, anti-convulsive and anti-psychotic drugs are among the therapeutic strategies for the management of the psychogeriatric patient. Atypical antipsychotics seem to be able to decrease the psychotic symptoms, with low levels of therapeutic failure. They also reduce extrapyramidal effects and the growth of prolactine hormone, which is quite useful when dealing with very old patients. Risperidone and olanzapine are two atypical anti-psychotics, which already proved to be adequate and well tolerated during the treatment of schizophrenia and of acute maniacal disorders. Our experience, with a population of patients followed by our Alzheimer Evaluation Unit (AEU), confirms that a low dose of olanzapine (5mg/day) and risperidone (0.5-1.0 mg/day) are effective in lowering behavioral disturbances, and psychotic symptoms due to dementia. Even in the long run,low doses of these drugs are still well tolerated. Higher levels of risperidone (> 1 mg/die)often caused extra-pyramidal symptoms such as rigidity and dyskinesia, whereas higher levels of olanzapine (> 5 mg/day) lead to an exceeding sedation. The management of behavioral disturbances is one of the most important goals in the global treatment of patients affected by dementia, to the extent of improving the quality of life. Atypical antipsychotics are preferable compared to old-generation drugs, therefore, they are the key therapeutic strategy we cannot renounce.

[Rehabilitation in Alzheimer's dementia]. / Riabilitazione nella demenza di Alzheimer.

Alzheimer's disease is a neurodegenerative disease that causes a progressive decline of cognitive and behavioural functions. The simultaneous presence of these disorders requires a treatment not only for cognitive decline, but also for behavioural symptoms, depression and caregiver's stress. Research has made many efforts to develop a wide range of treatments, different from current pharmacological therapy, which is not resolutive, owing to the absence of an exact etiopathogenetic mechanism. Since new drugs have not been shown to be really effective in slowing cognitive impairment, various forms of rehabilitative interventions have been proposed in order to treat Alzheimer's disease. Their efficacy in the improvement of cognitive functions is still not completely clear. Surely, interesting results have been obtained from studies about Reality Orientation Therapy, Occupational Therapy and Memory Training. Music therapy might provide a new form of rehabilitative intervention, especially acting on the reducing of behavioural symptoms. These alternative forms of non pharmacological treatment may have a positive effect on caregiver. The heavy emotional burden of seeing a loved one becoming confused and isolated and of having to accept new responsibilities, may be reduced by rehabilitative supports, complementary to the pharmacological therapy. Caregiver stress could be reduced in two ways: by promoting the hope that something is being done for the patient and providing free time for himself.