Prevalence of dementia in a southern European population in two different time periods: the ZARADEMP Project

OBJECTIVE: To compare the prevalence of dementia in two different time periods and two different studies. METHOD: Representative, random samples of the elderly (>65 years) in the Zaragoza Study or ZARADEMP-0 (n = 1080) completed the previous decade, and now in Wave I of the ZARADEMP Project or ZARADEMP-I (n = 3715) were interviewed. Standardized measures included the Geriatric Mental State and the History and Aetiology schedule. Cases of dementia were diagnosed according to DSM-IV criteria. RESULTS: Adjusted, global prevalence of dementia has not varied significantly: it was 5.2% (95% CI = 3.9-6.6) in ZARADEMP-0 and 3.9% (95% CI = 3.3-4.5) in ZARADEMP-I (prevalence ratio = 0.75; 95% CI = 0.56-1.02). However, the prevalence in ZARADEMP-I was significantly lower among men, particularly in all age groups between 70 and 84 years. CONCLUSION: Stability of the global prevalence of dementia in the elderly population has been documented. However, the decreased prevalence found in elderly men stimulated environmental hypotheses.     

Prevalence of dementia in a semi-urban population in Sri Lanka: report from a regional survey

BACKGROUND: The prevalence of dementia in Sri Lanka, which has a rapidly ageing population, is unknown. OBJECTIVE: This study aimed to determine the prevalence of Alzheimer's disease (AD) and other dementias in a semi-urban elderly Sinhala-speaking population in Ragama, Sri Lanka. METHODS: The study was conducted in two phases. Phase I: After informed consent 703 subjects aged > or =65 years from the study area (population 15 828) were screened for cognitive impairment using the Sinhalese Mini Mental State Examination. Subjects scoring < or =17 were regarded as suspected dementia cases. Phase II: All subjects who screened positive in phase I were included in phase II for detailed evaluation for dementia according DSM IV and NINCDS-ADRDA criteria which included structured neuropsychiatric assessment, laboratory investigations, an axial CT scan of the brain and an informant interview. RESULTS: In the study sample, 61% were female and 86% were between 65-75 years. 42 subjects screened positive in phase I. Of these, 28 subjects were diagnosed as having dementia, giving an overall prevalence rate of 3.98% (95% Confidence Intervals (CI) =2.6-5.7%). Of these, 20 (71.4%) had probable AD, four had vascular dementia (14.3%), two had mixed (vascular and AD) dementia (7.1%), one had Lewy body dementia, and one had dementia due to syphilis. Greater age, illiteracy and female gender were associated with higher prevalence of dementia. CONCLUSION: Comparison with other community studies performed in North India suggests that dementia prevalence is higher in Sri Lanka. This may be due to regional differences in disease incidence.     

Prevalence of Alzheimer's type dementia in an elderly Arab population.

The aim of this study was to estimate the prevalence of dementia of the Alzheimer type (DAT) in an Arab Israeli community. Epidemiological studies of dementia have rarely been reported in Arab populations. The target population, aged 60 years or older, comprised 821 persons (362 males) who, on 1 October 1995, were residents of the rural area of Wadi Ara. These persons were examined for symptoms of dementia (DSM-IV criteria), using a semistructured questionnaire for collection of demographic and medical data. Age, gender, and education-specific prevalence rates were calculated for this population and compared to those obtained in other studies. DAT was diagnosed in 20.5% of this population. Its prevalence increased steeply with age, from 8% among those younger than 70 years to 33% among those aged 70-79 and 51% among those 80 years or older. Illiteracy was very common in this population, and strongly associated with higher prevalence of DAT (27% vs. 4%, P < 0.001). DAT was more prevalent among females than males (25% vs. 15%, P < 0.001). However, illiteracy was also significantly more frequent among women (96% vs. 42%, P < 0.001). After correction for illiteracy, the gender difference lost statistical significance. Few women smoked, but among men, the prevalence of DAT in those who smoked was lower as compared to non-smokers (14% vs. 23%, a non-significant difference). These results were confirmed by logistic regression wherein DAT was included as the dependent variable and age, illiteracy, gender and smoking as independent variables (OR=2.8, 2.8, 1.2 and 0.7, respectively; P < 0.005 for each, except for smoking). Our findings suggest that this population is unique because of extremely high rates of dementia. While the results support a protective effect of schooling against the development of dementia, other factors (e.g. genetic) must be sought to explain this high frequency.     

Longitudinal changes in the prevalence of dementia in a Japanese rural area

Background: The increasing number of patients with dementia in Japan, together with the rapid aging of society, is currently considered to have a substantial impact on Japan's medical, economic and sociological systems. Therefore, the longitudinal estimation of changes in the prevalence of dementia based on accurate diagnostic evaluation has important implications. Methods: We undertook three separate epidemiological studies on long‐term changes, 10 years apart (1980, 1990 and 2000), in the prevalence of dementia in an elderly population using identical methods (DSM‐III and Hachinski's ischemic score) for the same rural area in Japan (Daisen‐cho). Results: The percentage of the population that was elderly (over 65 years of age) increased steadily from 16.0% in 1980 to 21.7% in 1990 and 27.1% in 2000. The prevalence of dementia (cases/100 people aged 65 years or older, adjusted to the population structure of 1980) in 1980, 1990 and 2000 was 4.4, 4.5 and 5.9, respectively, for all types of dementia, 1.9, 2.5 and 3.6, respectively, for Alzheimer‐type dementia (DAT) and 2.0, 1.7 and 2.2, respectively, for vascular dementia (VaD). Conclusions: These findings of an increase in the number of cases and prevalence of DAT and VaD in a Japanese rural community have important implications for interventional medicine.     

Prevalence of moderate and severe Alzheimer dementia and multi-infarct dementia in the population of southeastern Sicily

We have calculate the prevalence rates of moderate and severe dementia of the Alzheimer type (DAT) and of multi-infarct dementia (MID) in a Sicilian population sample aged 40 and over. For DAT the prevalence rate is 0.80% among the over 40s and 2.42% among the over 65s. The prevalence rates for both types, but especially for DAT, increase higher prevalence of primary degenerative dementia among females.

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Sommario Abbiamo calcolato i tassi di prevalenza della demenza tipo Alzheimer e della demenza multiinfartuale di grado moderato e severo in un campione di popolazione siciliana di 40 anni ed oltre (4337 individui). Per la DAT il tasso di prevalenza è dello 0,80% [LF al 95% 0,56–1,11] nella popolazione di 40 anni ed oltre e diventa pari al 2,42% [LF al 95% 1,69–3,37] nella popolazione che ha raggiunto e superato il 65esimo anno di età.Per la MID la prevalenza è di 0,34% [LF al 95% 0,19–0,56] nella popolazione di 40 anni ed oltre, mentre nella popolazione di 65 anni ed oltre la prevalenza è dello 0,95% [LF al 95% 0,50–1,62].La prevalenza dei due tipi di demenza, e per quella tipo Alzheimer in particolare, aumenta significativamente con l'età. Altrettanto significativa è, sempre per la demenza degenerativa primaria, la più elevata prevalenza nel sesso femminile.

     

Epidemiology of dementia in a Finnish population

An epidemiological study of dementia was carried out in the city of Turku (population 164,568) in Finland. A total of 421 patients with moderate to severe dementia were found. Degenerative dementia, i.e. presenile and senile dementia, was present in 218 patients (51.8 %), and in 152 patients (36.1 %) the dementia was associated with arteriosclerosis, including multi-infarct and combined dementia. The prevalence rate of dementia, all types, was 256 per 100,000 population, and 1,961 per 100,000 population over 65 years old. The age-specific prevalence rates of dementia increased with advancing age from 0.1 % in the age group 55–64 years to 11 % in the age group over 85 years. The peak annual incidence rate for all types of dementia was 58 per 100,000 population, and 447 per 100,000 population over 65 years old. Both prevalence and incidence figures suggested a female preponderance in dementia of degenerative origin and in dementia with associated arteriosclerosis.     

Prevalence and implications of psychopathological non‐cognitive symptoms in dementia

Objective: Clinical experience and recent population studies suggest that psychopathological, non‐cognitive symptoms are both frequent and relevant in dementia. Method: A representative community sample (n = 4,803 individuals, 55 + years) was interviewed in a two‐phase design. The Geriatric Mental Sate (GMS) was used for assessment and cases were diagnosed according to DSM‐IV‐TR criteria. Results: The prevalence of non‐cognitive symptoms (1 + symptoms) in cases of dementia (n = 223) was 90.1%, and negative‐type symptoms were most frequently found. A GMS ‘apathy‐related symptom cluster’ (anergia, restriction of activities and anhedonia) was significantly more frequent in the demented (55.6%) than in non‐cases (0.7%; specificity = 99.2%). In both dementia of Alzheimer’s type and vascular dementia, number of symptoms tended to be inversely related to severity of dementia, but psychopathological profiles differed. Conclusion: Non‐cognitive, negative‐type symptoms are very frequent in cases of dementia living in the community. They have powerful specificity in the distinction with non‐cases, and might change current concepts of dementia.     

Prevalence of Alzheimer's disease with diabetes in the Japanese population

Background:  The aim of the present study was to estimate the prevalence of impaired cognitive function and Alzheimer's disease (AD) in diabetic subjects from Japan.
Methods:  In the present study, 386 Japanese diabetic subjects aged more than 50 years were initially screened with the 'brief screening test' for AD, and were diagnosed with AD and vascular dementia (VaD) according to the criteria of the NINCDS-ADRDA and the NINDS-AIREN. We compared the prevalence of dementia in diabetic patients with that in ordinary subjects, and analyzed the association of the status of diabetes with dementia including AD and VaD.
Results:  Forty-six (11.9%) patients were diagnosed with dementia, including 13 (3.4%) patients with AD and nine (2.3%) patients with VaD. Of the 221 subjects aged more than 65 years, 39 (17.6%) patients had dementia, including 13 (5.9%) patients with AD and eight (3.6%) patients with VaD. Compared with ordinary subjects, the prevalence of dementia in the present study was more frequent than the prevalence of dementia for the general population in almost each age group examined. There was also a greater prevalence of AD and VaD in subjects aged over 65 years in the present study. In the present study, AD subjects had significantly higher levels of fasting plasma glucose (FPG; 247.5 ± 116.3 mg/dL; P  < 0.05) and glycosylated hemoglobin (HbA1c; 8.8 ± 1.9%; P  < 0.01) compared with non-demented subjects. In AD patients, the odds ratios of FPG and HbA1c were also significantly higher (1.02 and 2.07, respectively; both P  < 0.01).
Conclusion:  The present study shows that diabetes can be associated with impaired cognitive function, particularly AD, in Japanese subjects.     

Prevalence of restless legs syndrome in a Japanese elderly population

ObjectiveTo estimate the prevalence of restless leg syndrome (RLS) in elderly Japanese people by means of a population-based survey of subjects aged ≥65 years.BackgroundStudies conducted worldwide have revealed large variations in the prevalence of RLS among different populations. However, few studies have been done in Japan.MethodsA population-based survey was carried out from 2003 to 2006 through a local healthcare project in the small town of Ajimu in a rural area of southern Japan. A Japanese translation of the questionnaire covering the four features of RLS as defined by the International RLS Study Group in 1995 was used to confirm the diagnosis of RLS. All participants aged ≥65 years were invited to fill out the questionnaire. Subjects with positive results underwent face-to-face interviews.ResultsA total of 1251 persons (men, 35%; mean age, 75.0 ± 6.1 years) answered the questionnaire. Of these 1251 participants, 70 (5.6%) (men, 20%; mean age, 75 ± 4.9 years) answered the questions on RLS positively. Face-to-face interviews and examination confirmed the diagnosis of RLS in 12 subjects. Therefore the overall prevalence of RLS in the elderly Japanese population was estimated at 0.96%, with a higher prevalence in women (1.23%) than in men (0.46%).ConclusionThe overall prevalence of RLS among inhabitants of Ajimu aged ≥65 years is 0.96%. Most of the subjects identified were women. The prevalence of RLS is lower in Japan than in studies conducted in European and North American populations.     

Elderly Japanese emigrants to Brazil before World War II: II. Prevalence of senile dementia

BACKGROUND: We previously showed the prevalence of dementia in the town of Tajiri (Miyagi Prefecture, Japan), and found it to be 8.0%.The first population-based study on dementia in Brazil (Catanduva) disclosed the prevalence as being 7.1%. To evaluate the effects of environment on development of dementia, elderly Japanese immigrants living in Brazil were examined. Brazil is the country with the largest number of Japanese immigrants. METHODS: All immigrants aged 65 years and over from Miyagi Prefecture, living in the four cities of the S?o Paulo Metropolitan area were targeted (n = 192). We were able to examine 166 subjects (86.5%). The diagnosis of dementia was based on the DSM-IV with the severity assessed by the CDR (clinical dementia rating) scales. The cognitive ability screening instrument (CASI) was used for neuropsychological assessment. RESULTS: Thirteen subjects were diagnosed with dementia, CDR 1-3, the prevalence being 7.8%. Older subjects suffered more from dementia, and, paradoxically, the more highly educated subjects also suffered more. All the CASI items, except for long-term memory and visual construction, significantly deteriorated in the CDR 0.5 group compared with the CDR 0 group. COMMENTS: The prevalence of dementia was not thought to be affected by environmental factors. A paradoxically higher rate of dementia in the more educated subjects was probably due to the historical problems of the immigrants. Intact CASI item long-term memory in the CDR 0.5 group indicated that suspected dementia patients could maintain this function. This is the first epidemiological study on dementia in elderly Japanese immigrants in Brazil.     

Prevalence of very mild to severe dementia in Denmark

Objectives - The prevalence of dementia has been estimated in several countries and a meta-analysis has shown moderate and severe dementia in people aged 65 years and older to be between 4% and 6%. The Odense study is aiming to estimate the prevalence and incidence of dementia and to identify risk factors. Material and methods - A total of 3346 persons, equivalent to 64.5% of a random sample of 5237 persons aged 65–84 years living in the municipality of Odense, Denmark, underwent a two phase diagnostic procedure including a screening with CAMCOG, the cognitive section of The Cambridge Examination for Mental Disorders of the Elderly, seven neuropsychological tests, medical examination, and CT scan. The severity of dementia was assessed by the CDR (Clinical Dementia Rating). Results - The prevalence rate was 7.1%, including the very mildly demented, defined as persons rated questionably demented according to the CDR scale. The prevalence rate of very mild dementia was 2.8%. The proportion of cases with very mild dementia decreased with increasing age while the prevalence rate increased. Conclusion - Inclusion of very mild cases of dementia resulted in a higher prevalence rate than generally reported, and the prevalence rate increased exponentially with age which was mainly due to Alzheimer's disease.     

Prevalence of Alzheimer's disease, vascular dementia and dementia with Lewy bodies in a Japanese population

We studied the prevalence of dementing disorders in a rural town of Japan (Amino-cho), using a door-to-door two-phase design. Of the 170 persons screened as having cognitive impairment, 142 cases were diagnosed as having dementia. The prevalence (cases/100 aged 65 years older) was 3.8 for all types of dementia, 2.1 for Alzheimer's disease (AD), 1.0 for vascular dementia (VD) and 0.7 for other types of dementia. Among other types of dementia, there were four male patients with dementia with Lewy bodies (prevalence: 0.1), but no patients with frontotemporal lobar degeneration. The overall prevalence was higher in women for AD, while that of VD was the same in both sexes. With results similar to many previous studies in Western countries and some recent surveys in Japan, the present sudy clearly showed that AD is more prevalent than VD.     

Factors contributing to caregiver burden in dementia in a country without formal caregiver support

Objectives: To investigate caregiver burden in dementia and explore factors associated with different types of burden in a country without formal caregiver support using a province in China as a case.Method: Cross-sectional questionnaire survey was used to collect data. One hundred and fifty-two family caregivers of people with dementia in community settings were recruited from 2012 to 2013 using convenience sampling. Objective burden was measured by caregiving hours and dementia-related financial burden. Subjective burden was measured and analysed using the Caregiver Burden Inventory and the Neuropsychiatric Inventory-Questionnaire. Multivariate regression models were employed to analyse factors associated with each type of subjective burden.Results: Five types of subjective burden were measured by the Caregiver Burden Inventory, namely, physical burden, emotional burden, time-dependence burden, developmental burden, and social burden. Caregiver distress, as a subjective burden, was measured by the Neuropsychiatric Inventory-Questionnaire and reported by relating to the severity of care recipients’ behavioural and psychological symptoms of dementia. This caregiver cohort showed a high level of physical, time-dependence, and developmental burdens, but a low level of emotional and social burdens. Factors contributing to each type of subjective burden measured by the Caregiver Burden Inventory differed from each other.Conclusion: The high level of objective and subjective burdens identified in this study suggests that government-funded formal caregiver support should be established and services should be designed to target different types of burdens and factors contributing to these burdens.     

Prevalence of dementia in the city of Helsinki

The Helsinki Aging Study is based on a random sample of 795 subjects aged 75-years (N = 274), 80-years (N = 266) and 85-years (N = 255). A clinical examination including Clinical Dementia Rating (CDR)-scale was carried out in 82% of the cases. 93 demented subjects were found, 17 of whom had mild dementia. The prevalence of moderate and severe dementia was 2.9%, 10.3% and 23.3% in the age groups of 75-year-olds, 80-year-olds and 85-year-olds, respectively. If we take into account also the mild cases, we get the prevalence of dementia 4.6%, 13.1% and 26.7% in the above mentioned age groups, respectively. The proportion of mild dementias was lower than expected, which probably reflects both the difficulties to recognize mild dementia in an elderly population and the relatively small compensatory capacity of elderly people.     

Prevalence and predominance of Alzheimer type dementia in rural Japan

Background: The aim of the present study was to estimate prevalence rates of dementia and its subtypes in the population aged 65 years or more in a rural area of Japan. Methods: A survey was conducted in Itoigawa, a city with 33 120 inhabitants in Niigata Prefecture, Japan. There were 7847 persons aged 65 years or older, and they comprised 23.4% of the total population. The first phase survey included questions on medical history, activities of daily living, psychiatric and behavioral symptoms and MMSE. When the responses were examined 6394 valid replies were received (81.5%) and 914 subjects were identified who were suspected of having dementia. In addition, 200 samples were selected randomly as controls from the 5480 people who were not suspected of dementia. The second phase survey was applied to a total of 1114 subjects. Pairs of psychiatrists and nurses made house‐to‐house visits and examined the subjects in detail. Clinical diagnoses of the subtypes of dementia were based on the criteria set out by the Consortium to Establish a Registry for Alzheimer's Disease and DSM IV. Results: The prevalence rate of dementia was estimated at 6.2% (men 4.5%, women 7.4%), which is higher than that found by previous reports in Japan. Alzheimer type dementia was the most frequent diagnosis, accounting for 4.0%, followed by vascular dementia (1.2%), other type of dementia (0.3%) and unknown dementia (0.8%). ‘Questionable dementia’, as defined by the Clinical Dementia Rating 0.5, was found in 4.4% of respondents (men 6.3%, women 3.0%). Conclusions: The prevalence of dementia in a rural area was higher than that of previous Japanese reports, and the prevalence rate of Alzheimer type dementia was much higher than that of vascular dementia.     

Prevalence of Dementia Among the Elderly in a Japanese Community Population—Comparative Study on the 1983 and 1996 Survey: The Aichi Study

Background: An epidemiological survey of dementia among community residents over 65 years of age in Aichi Prefecture (Japan) was conducted in 1983 and 1996. We compared the prevalence rates of dementia in 1996, with the previously published rates of 1983.
Methods: The study employed a two-stage design. First stage: A test based on the DSM-III-R criteria for dementia was administered to all participating residents, who were randomly drawn from the resident register (856,879) of Aichi Prefecture in 1995 (495,923 in 1983). Second stage: A detailed clinical and cognitive evaluation (including MMSE and neurological examination) of the subjects identified in the first stage was carried out by trained psychiatrists.
Results: The prevalence rate for dementia in 1996 was 4.8% (moderate and severe 2.1%) compared with 5.8% (2.2%) in 1983; for senile dementia of Alzheimer type (SDAT) it was 2.8% in 1996 and 2.4% in 1983; for cerebrovascular dementia (CVD), 1.8% in 1996 and 2.8% in 1983.
Conclusion: Up to this time, the cases of CVD have been more frequent than those of SDAT in Japan, especially in the urban areas. However, the relationship between CVD and SDAT has now reversed. These data suggest that SDAT is a common condition and that its public health impact will continue to increase with the increasing longevity of the population in Japan.