Neuropsychiatric symptoms in South‐East Asian patients with mild cognitive impairment and dementia: prevalence,subtypes, and risk factors

Background

The subtypes and risk factors of neuropsychiatric symptoms remain largely unexplored in South‐East Asian populations.

Objective

We investigated the prevalence, subtypes, and risk factors, namely, demographic, medical morbidity, and cognitive impairment associated with neuropsychiatric symptoms in a South‐East Asian cohort of patients with mild cognitive impairment (MCI) and dementia.

Methods

A clinical cohort of 38 MCI and 198 mild–moderate dementia patients were assessed using the Neuropsychiatric Inventory‐Questionnaire.

Results

Neuropsychiatric symptoms were equally prevalent among patients with MCI (74%) and mild–moderate dementia (85%). Three subtypes of symptoms were identified for each diagnostic group; for MCI, they included mood disturbances, anxiety/sleep problems, and psychosis, while for dementia, the subtypes included behavioral disturbances, psychosis/mood, and hyperactive behaviors. The largest risk for neuropsychiatric symptoms for both MCI and dementia patients was male gender. Among patients with MCI, burden of cerebrovascular disease and global cognitive impairment were small risks for neuropsychiatric symptoms, while for patients with dementia, an older age (>65 years) was a small risk and lower educational attainment was a moderate risk.

Discussion

These findings contribute to the worldwide epidemiology of neuropsychiatric symptoms in MCI and dementia and highlight that the profile of symptoms, subtypes, and risks is fairly homogenous across Western and Asian cultures. Copyright © 2017 John Wiley & Sons, Ltd.     

Neuropsychiatric symptoms in the community-based patients with mild cognitive impairment and the influence of demographic factors

OBJECTIVE: To investigate the pattern of neuropsychiatric symptoms of MCI patients in the Thai population and the influence of demographic factors on the symptoms. METHODS: One hundred and seven participants aged 50 and over diagnosed with MCI (n = 77) and normal (n = 30) were recruited from a community-based unit. The Neuropsychiatric Inventory (NPI) was used to assess behavioral disturbances in the subjects. RESULTS: Compared to normal subjects, MCI patients had higher incidence of anxiety (53% vs 27%, p = 0.013), dysphoria (46% vs 17%, p = 0.006), and sleep problem (45% vs 23%, p = 0.035). Although marginally significant, apathy was more common in MCI patients (12% vs 0%, p = 0.059). The mean total NPI score and NPI distress score were higher in the MCI group (6.8 vs 1.9, p < 0.0005 and 2.9 vs 0.6, p = 0.01, respectively). The MCI patients aged over 65 had higher incidence of hallucinations (18.9% vs 0%, p = 0.018). Males and patients of poor financial status had higher percentage of dysphoria compared to female and patients with better financial status (65% vs 38.5%, p = 0.041 and 75% vs 37.9%, p = 0.008, respectively). Patients with poor financial status also had higher percentage of anxiety (81.3% vs 44.5%, p = 0.01). CONCLUSIONS: MCI is associated with significant neuropsychiatric symptoms which caused caregiver distress. In this study, the pattern of neuropsychiatric symptoms in a Thai MCI population was similar to those reported in western countries. Age, sex, educational level and financial status influenced the neuropsychiatric symptoms of MCI patients.     

Conceptualization of mild cognitive impairment: a review

BACKGROUND: Several factors have prompted renewed interest in the concept of declines in cognitive function that occur in association with aging, in particular the area between normal cognition and dementia. We review the changing conceptualization of what has come to be known as mild cognitive impairment (MCI) in an effort to identify recent developments and highlight areas of controversy. METHODS: Standard MEDLINE search for relevant English-language publications on mild cognitive impairment and its associated terms, supplemented by hand searches of pertinent reference lists. RESULTS: Many conditions cause cognitive impairment which does not meet current criteria for dementia. Within this heterogenous group, termed 'Cognitive Impairment, No Dementia' (CIND), there are disorders associated with an increased risk of progression to dementia. Still, the conceptualization of these latter disorders remains in flux, with variability around assumptions about aging, the relationship between impairment and disease, and how concomitant functional impairment is classified. Amongst patients with MCI, especially its amnestic form, many will progress to Alzheimer's disease (AD). In contrast with clinic-based studies, where progression is more uniform, population-based studies suggest that the MCI classification is unstable in that context. In addition to Amnestic Mild Cognitive Impairment (AMCI), other syndromes exist and can progress to dementia. For example, an identifiable group with vascular cognitive impairment without dementia shows a higher risk of progression to vascular dementia, Alzheimer's disease and mixed dementia. CONCLUSIONS: Recent attempts to profile patients at an increased risk of dementia suggest that this can be done in skilled hands, especially in people whose symptoms prompt them to seek medical attention. Whether these people actually have early AD remains to be determined. The more narrowly defined MCI profiles need to be understood in a population context of CIND.     

Prevalence of mild cognitive impairment: a population-based study in elderly subjects

OBJECTIVES: Mild cognitive impairment (MCI) has been suggested as a term for a boundary area between normal aging and dementia, especially Alzheimer's disease (AD). In follow-up studies, more than 50% of MCI subjects have been converted to dementia in 3-4 years. However, the epidemiology of MCI is not well known. This study was designed to determine the prevalence of MCI in an elderly population. METHODS: A total of 806 subjects (60-76 years of age) from a population-based random sample of 1150 subjects living in the city of Kuopio in eastern Finland were evaluated. Neuropsychological tests and a structured interview including the modified Clinical Dementia Rating (CDR) were used to apply the diagnostic criteria of MCI as proposed by Mayo Clinic Alzheimer's Disease Research Centre. Thus, subjects having a test score more than 1.5 SDs below the age appropriate mean in memory tests and a CDR score of 0.5 but no dementia, were diagnosed as having MCI. RESULTS: A total of 43 subjects, 5.3%, met the MCI criteria. MCI was more prevalent in older and less-educated subjects, but no difference was found between men and women. The CDR appeared to be the most important part of the criteria. The memory tests had less impact on prevalence variables. CONCLUSIONS: The low prevalence of MCI indicate that in a population-based study design its criteria may identify a more homogeneous group of subjects at the lower end of the cognitive continuum as contrasted with various other criteria of cognitive impairment in the elderly population. This is compatible with follow-up studies showing a high probability of dementia in the MCI group. Thus, probable candidates for trials of preventive intervention for dementia can be screened from the elderly population using these diagnostic criteria.     

Disability and mild cognitive impairment: a longitudinal population-based study.

OBJECTIVE: To determine whether mild cognitive deficit is associated with parallel changes in ability to perform activities of daily living. BACKGROUND: While considerable research has been conducted on the effect of senile dementia and other neurodegenerative disorders on ability to perform everyday activities, little is known about the much larger group of elderly persons suffering from mild cognitive deficits. METHODS: Disability prevalence was estimated in 368 persons over the age of 65 years recruited from the general population via a general practitioner network. Subjects were followed over a 3-year period using computerized cognitive assessment and observations of everyday functioning. Standardized neurological assessment in the third year permitted the identification of subjects who have evolved towards dementia. RESULTS: An overall disability prevalence was found in the general population of 26.3%, with 30.8% in subjects with sub-clinical cognitive impairment. Longitudinal follow-up showed cognitive decline over time without dementia to be paralleled by changes in activity performance, with visuospatial deficits having the most marked effect on overall functioning. High intelligence quotient (IQ) and education are seen to reduce the degree of activity loss, but only when senile dementia is not present. CONCLUSIONS: Difficulties in the performance of everyday activities were found more frequently in non-demented subjects with mild cognitive deficits than in the general population. High pre-morbid levels of ability are seen to have a protective effect. A diagnosis of dementia should not therefore be required by persons with cognitive impairment applying for home help.     

CERAD test performances in amnestic mild cognitive impairment and Alzheimer's disease

OBJECTIVES: The aim of the study was to examine the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) test performances cross-sectionally in patients suffering from amnestic mild cognitive impairment (MCI) and mild Alzheimer's disease (AD). Moreover, we wanted to determine the sensitivity to amnestic MCI and mild AD, as well as the specificity of different CERAD subtests in our study groups. MATERIAL AND METHODS: Fifteen healthy elderly individuals, 15 amnestic MCI patients and 15 probable AD patients suffering from mild dementia were tested with the CERAD neurocognitive dementia screening test. RESULTS: Significant differences were found in all CERAD tests except Constructional praxis (copy) and Clock drawing between the controls and the AD group. The MCI group was differentiated from the controls only in the Wordlist learning test. In the language tests the sensitivity to MCI and AD was quite low and the specificity very high. In the savings scores the sensitivity to AD was high, but the specificity rather low. The Wordlist recognition test screened no false positives using the current cut-off score and the sensitivity to AD was 0.6, but only one MCI patient was detected using the current cut-off score. Raising the cut-off score also raised the sensitivity to MCI without dramatic loss of specificity. Cut-off scores for the Wordlist learning test and Wordlist delayed recall, which have been found to differentiate normal aging from dementia, are lacking in the Finnish CERAD. The current data indicates that the Wordlist learning test might be relatively sensitive to MCI. CONCLUSIONS: The results indicate that the Finnish CERAD test battery with its current cut-off scores has low sensitivity to MCI, and using it as a sole cognitive screening instrument for MCI and preclinical dementia might result in false negatives.     

From mild cognitive impairment to dementia: a prevalence study in a district of Tuscany, Italy

OBJECTIVE: A door-to-door two-phase study was designed in order to estimate the prevalence of cognitive deficit amongst the residents of a district in Tuscany (central Italy). Identification of cases with mild cognitive impairment (MCI) was given high priority, because this condition has been suggested as a term for the boundary area between normal aging and dementia. METHODS: Of the 1600 subjects who completed the screening phase, 354 scored under the cut-off point of the Mini Mental State Examination and Clinical Dementia Rating and were investigated by means of a standardized diagnostic protocol. RESULTS: The prevalence of MCI and age-related cognitive decline was 4.9 and 9.3%, respectively; low levels of education significantly increased the risk of these conditions. The prevalence of dementia over age 65 was 6.2%, with a significant risk association with age. In our population, Alzheimer's disease was the most frequent type of dementia (prevalence rate 4.2%) and increased risk depending on age, sex and education has been found. CONCLUSIONS: Our findings are somewhat similar to previous studies. Further epidemiological and longitudinal studies are warranted to identify which diagnostic category is more predictive for dementia.     

Psychiatric symptoms/syndromes in elderly persons with mild cognitive impairment. Data from a cross-sectional study

Objective – This study examined the prevalence of psychiatric syndromes and symptoms in elderly persons with mild cognitive impairment (MCI).
Methods – Data from a population-based study (the Kungsholmen Project) were used. All subjects with a Mini-Mental State Examination (MMSE) score ≤23 and a comparable random of those ≥24 were selected for further examination. Physicians carefully examined the included persons and those affected with dementia were excluded. The rest were stratified into 14 groups according to age and level of education. The mean MMSE score was calculated for each group and those subjects with scores 1SD below the age- and education-specific mean were classified as MCI. A structured psychiatric interview was performed and diagnoses of depression, anxiety and psychosis were made according to DSM-III-R.
Results – Being suspicious was the only symptom and being affected by an anxiety syndrome was the only diagnosis found to be associated with MCI. The association with suspiciousness might reflect the feeling of losing control that probably accompanies the loss of cognitive function experienced by the person. The association with anxiety syndromes might be a result of the fact that physical disorders have been reported to be more common in persons with cognitive impairment, as well as in persons with anxiety syndromes.
Conclusion – The results of this study suggest that the psychiatric syndromes present in MCI might be related to MCI per se . Additionally, it might reflect a developing dementia or a concomitant physical disorder.     

Repetition priming in mild cognitive impairment and mild dementia: Impact of educational attainment

Objective: To examine the role of education on repetition priming performances in healthy aging, mild cognitive impairment (MCI), and mild dementia.

Method: A total of 72 participants (healthy = 27, with MCI = 28, with mild dementia = 17) took part in the present study. Priming was assessed using the Word Stem Completion Test, and delayed and recognition memory was assessed using the Rey Auditory Verbal Learning Test. A multinomial regression analysis was used to examine whether years of education moderated priming and declarative memory performances in predicting group membership.

Results: Priming performances discriminated between individuals with MCI and mild dementia but not between MCI and healthy. Additionally, this effect was most salient in individuals with low levels of education. Education did not moderate explicit memory performances in predicting group membership.

Conclusion: Little is known about the impact of education on priming in verbal memory. Our findings indicate that formal years of education impact priming performances in MCI and individuals with mild dementia, which may have implications for designing interventions targeting “intact” cognitive abilities in these groups.