Prevalence of Dementia and its Determinants among Elderly Individuals Residing in Community Settings

Chapter 9 - Epidemiology of aging and associated cognitive disorders: Prevalence and incidence of Alzheimer's disease and other dementias

China is an ageing society, with around 150 million people aged 60 years or older. The prevalence of dementia will increase by more than 100% in the coming 20 years. This study aimed to investigate the prevalence and effects of dementia among the community elderly in Chongqing, China. Cluster sampling was adopted. A sample of elderly individuals aged 60 years and older was extracted as research subjects from three counties within Chongqing, China. One-on-one interviews were conducted through a general information questionnaire, and the Mini-Mental State Examination, Instrumental Activity of Daily Living Scale, and Geriatric Depression Scale were administered. The investigated data were tested by χ2 , and the effect factors of dementia were analyzed by multiple logistic regression analysis. Statistical significance was set at P < 0.05. We distributed 1850 questionnaire, and the response rate was 100%. However, only 1781 questionnaires were able to be used in the study. Of the 1781 elderly respondents, 186 (10.44%) presented with dementia. Our findings revealed that differences in regions, age, marital status, education level, occupation, tobacco consumption, alcohol consumption, freshwater fish consumption, exercise, intensive labour, mah-jong- and chess-playing habits, media consumption (i.e. watching TV, listening to the radio, or reading the newspaper), body mass index, hypertension, coronary heart disease, and depression were statistically significant in the prevalence of dementia (P < 0.05). According to multiple logistic regression analyses, living in a rural area, older age, being single, obesity, hypertension, coronary heart disease, and depression are risk factors for dementia. In contrast, cessation of smoking, freshwater fish consumption, moderate or frequent exercise, intensive labour, daily housework, outdoor activities, media consumption, and social activities are protective factors against dementia among community elderly in Chongqing, China.

Aims: In order to determine the prevalence of dementia and mild cognitive impairment (MCI), we conducted a population-based study in Japan. Methods: Participants included 924 subjects aged 65 years or older who resided in the town of Ama-cho. In phase 1 of the study, the Mini-Mental State Examination and Clinical Dementia Rating were administered for screening purposes. In phase 2 of the study, the subjects who screened positive were further examined by neurologists. Dementia and MCI were diagnosed by means of DSM-IV and International Working Group on MCI criteria, respectively. Results: By the prevalence date of June 1, 2010, 24 subjects had deceased or lived outside the town. In total, 723 of the remaining 900 subjects received a phase 1 test. In phase 2, 98 subjects were diagnosed with amnestic MCI, 113 subjects with non-amnestic MCI, and 82 subjects with dementia. Of the subjects who did not receive the phase 1 test, 66 subjects were diagnosed as having dementia according to data from their town medical card or the Long-term Care Insurance System. The crude prevalence of amnestic MCI, non-amnestic MCI, and dementia were 10.9, 12.6, and 16.4%, respectively. Conclusion: Consistent with the striking increase in the number of elderly individuals, we report higher prevalence of MCI and dementia in Japan than previously described.

Background:With a rapidly increasing population of older aged people, epidemiological data regarding the prevalence of mental and physical illnesses are urgently required for proper health planning. However, there is a scarcity of such data from India.Aims:To study the frequency and pattern of psychiatric morbidity present and the association of physical illness with psychiatric morbidity in an elderly urban population.Settings and Design:Cross-sectional, epidemiological study.Materials and Methods:All the consenting elderly persons in a municipal ward division (n=202) were enrolled after surveying a total adult population of 7239 people. A door to door survey was undertaken where the participants were interviewed and physically examined. General Health Questionnaire-12, Mini Mental State Examination, CAGE Questionnaire and Geriatric Depression Scale were used in the interview apart from consulting the available documents. Other family members were also interviewed to verify the information.Statistical Analysis:Chi-square test with Yates correction.Results:Psychiatric illnesses were detected in 26.7% while physical illnesses were present in 69.8% of the population surveyed. Predominant psychiatric diagnoses were depressive disorders, dementia, generalized anxiety disorder, alcohol dependence and bipolar disorder. The most common physical illness was visual impairment, followed by cardiovascular disease, rheumatic illnesses, pulmonary illnesses, hearing impairment, genitourinary diseases and neurological disorders. Presence of dementia was associated with increased age, single/widowed/separated status, nuclear family, economic dependence, low education, cardiovascular disorders, rheumatic disorders and neurological disorders. Depression was associated with female sex, single/widowed/separated status, staying in nuclear families, economic dependence on others and co-morbid physical illnesses, specifically cardiovascular disorders and visual impairment.Conclusions:This study presented a higher rate of dementia and old age depression. The interesting association with several sociodemographic factors as well as physical illnesses may have important implications for health planning.

The rapid growth of the elderly population in Brazil has implied a significant rise in the number of individuals with dementia. The real prevalence of this disease needs to be ascertained in order to establish appropriate measures for improving the quality of life of those affected. The aim of this study was to estimate the prevalence of dementia among elderly Brazilians (≥ 60 years) through a systematic review of high-quality, population-based, double-blind studies published between 1990 and 2010. Systematic review of prevalence studies. The manuscript was produced in the School of Medicine, Universidade de Brasília. Database searches for articles were conducted in Medline (Medical Literature Analysis and Retrieval System Online), Embase (Excerpta Medica database), Lilacs (Literatura Latino-Americana e do Caribe em Ciências da Saúde), SciELO (Scientific Electronic Library Online) and theses and dissertations, using specific keywords. Quality was assessed according to eight criteria for sampling and measurement of findings. Out of 112 articles identified, eleven were included in the qualitative synthesis. In five higher-quality studies from São Paulo, the prevalence rates ranged from 5.1 to 19.0%. No meta-analysis was presented because of heterogeneity among the studies. Poor, illiterate, female and very elderly individuals were the groups most affected. The findings from this review did not reflect the reality of the whole country. Although the results brought some information on the prevalence and distribution of dementia in Brazil, cross-sectional studies with consistent methodology are needed.

Background: Depression and dementia are mental health problems that are encountered in elderly in india. it is imperative for us to recognize these symptoms in elderly and treat them appropriately. Thus we intended to study the prevalence and risk factors of depression and dementia in geriatric population in selected field practice area of Hassan Medical College.Methods:A community based descriptive study was conducted among 231 individuals in geriatric age group aged 60 and above, over a period of 2 months. The sample size was estimated based on the prevalence of depression as 31% stated in one of the large community based study using similar scale. Geriatric Depression Scale-15 (GDS-15) was used to screen for depressive disorders and Barthel Index to grade their physical activity. Dementia among elderly was screened with a vernacular adaptation of the Hindi Mental State Examination tool (HMSE).Results: Among 231 individuals, 150 (64.93%) were females and 81 (35.06%) were males. 45.88% of them had no formal education. Among 231 elderly individuals, 13 cases of dementia were identified with a prevalence rate of 5.6%. Total prevalence of depression was found to be 60.17%. Higher prevalence of dementia was found in females (6.6%), age above 80 years (18.7%), unemployed and labourers (7.4%), illiterates (7.4%), low SES (6.5%) and dependents (7.5%).Conclusions:Depression and dementia are important health problems of the elderly population. Simple tools used in this study can be used at primary health care settings for early identification of dementia and depression in the elderly population.

An increasing body of evidence shows that individuals diagnosed with congestive heart failure (CHF) are at a higher risk for dementia. However, the prevalence rate of dementia among persons with CHF in very old individuals has not been previously reported, and little is known about the comorbidities that place old persons with CHF at a higher risk for dementia. The aim of this study was to compare the prevalence of dementia in individuals 80 years or older who have CHF with that in individuals without CHF and to identify factors related to dementia in individuals diagnosed with CHF. A total of 702 participants from a Swedish population-based longitudinal study (Octogenerian Twin) were included. The group consisted of same-sex twin pairs, age 80 years or older, and 138 participants had CHF. Dementia was diagnosed according to criteria in the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised. Generalized estimating equations including gender, age and educational level, waist circumference, diabetes, hypertension, smoking, depression, and blood values were used in a case-control analysis. Individuals with CHF had a significantly higher prevalence of vascular dementia, 16% vs 6% (P < 0.001), and of all types of dementia, 40% vs 30% (P < 0.01), than those not diagnosed with CHF. The generalized estimating equation models showed that depression, hypertension, and/or increased levels of homocysteine were all associated with a higher risk for dementia in individuals with CHF. Diabetes was specifically associated with an increased risk for vascular dementia. The prevalence of dementia was higher among individuals with CHF than in those without CHF. Diabetes, depression, and hypertension in patients with CHF require special attention from healthcare professionals because these conditions are associated with an elevated risk for dementia. Higher levels of homocysteine were also found to be a marker of dementia in patients with CHF. Further research is needed to identify the factors related to dementia in individuals 80 years or older diagnosed with CHF.

The prevalence of dementia in urban and rural areas of China

BackgroundMalawians, in Sub‐Saharan Africa (SSA), face the double burden of HIV and Alzheimer’s disease and related dementia (ADRD). The life expectancy among HIV‐positive people on antiretroviral therapy has increased consistently over the past 25 years. The purpose of the study was to determine the prevalence of dementia among people living with HIV (PLWHIV) and the general population without HIV as a comparison group in Malawi.MethodsWe conducted a retrospective medical records review of four hundred consecutive patients from a single tertiary health center (200 PLWHIV from the HIV clinic and 200 without HIV from an outpatient clinic) in Lilongwe, Malawi. Since there was no electronic medical records system in Malawi, trained data collectors manually reviewed the medical records based on the instrument devices and the definitions between August 2023 and October 2023. We examined dementia prevalence and clinical characteristics including age, gender, and other clinical history between PLWHIV and the comparison group.ResultsThe PLWHIV group was significantly younger than the comparison group (mean age = 44.23±8.07 vs. 57.67±16.28; p&lt;2e‐16), while there was no significant difference in sex (male 55% vs. 50%; p = 0.37). The overall prevalence of dementia was higher in PLWHIV than that in the comparison group (22% vs. 10%; p = 1.4e‐03 before adjusting for age and p = 1.9e‐07 after adjusting for age). Prevalence difference was higher in the older individuals (age&gt;50; 39% vs. 13%; p = 3.2e‐4 before adjusting for age and p = 4.9e‐07 after adjusting for age). Dementia increased with age in both groups: 13% (age&lt;45), 17% (45‐64), and 22% (65 and over), but more rapidly in PLWHIV than in the comparison group (17%, 28% and 50% vs. 5%, 4% and 20% respectively).ConclusionThis is the first study to demonstrate prevalence of dementia in PLWHIV was significantly higher than that of the general population in Malawi. We confirmed the increased risk of dementia in PLWHIV and provided valuable groundwork for future ADRD research in SSA, specifically in Malawi.

TRENDS IN RACIAL AND ETHNIC DIFFERENCES IN DEMENTIA PREVALENCE RATES AND DISEASE AWARENESS

BackgroundAging is linked to an increased risk of dementia, a significant cause of functional decline in the elderly, necessitating long‐term care.MethodsDementia prevalence rates by age categories were obtained for bed‐bound or home‐bound elderly individuals from a public health system’s home care service in communities of Belo Horizonte/MG, to assess the independent effect of age. Analyses were conducted using Stata/SE for Macintosh 12.0 and included descriptive measures and adjusted prevalence ratios using Poisson Regression analysis with robust standard deviations. Results were considered significant at p&lt;0.05.ResultsA total of 1,092 dementia patients were evaluated, aged 70‐79 (28.6%), 80‐84 (19.9%), and 85‐90 (18.9%). Over half had less than 4 years of education (53.5%). The primary etiologies of dementia were Alzheimer’s disease alone (28%), isolated vascular dementia (13.8%), and mixed dementia (10.9%). The prevalence of other etiologies like frontotemporal dementia, Lewy body dementia, and dementia associated with Parkinson’s disease were low. Dementia prevalence by age group was 39.4% (60‐69 years); 55.6% (70‐79); 58.3% (80‐84); 69.6% (85‐89); 72.2% (90‐94) and 79.1% (95 years or older). Compared to the age group 60‐69 years, the PR was 1.4 for 70‐79; 1.5 for 80‐84; 1.8 for 85‐89; 1.9 for 90‐94; and 2.1 for 95 years or older (p&lt;0.005 for all PRs). The average Charlson Comorbidity Index (CCI) was 5.1 (standard deviation 1.8), and the proportion of frail elderly was 95%. Poisson regression revealed that dementia prevalence was not affected by CCI or education level, but there was an independent effect of age group and frailty. Male gender was negatively and independently associated with dementia (PR = 0.80; p&lt;0.001), while frailty was positively and independently associated with dementia (PR = 14.9; p&lt;0.001).ConclusionThe primary cause of dementia was Alzheimer’s disease, following the pattern reported in the literature. Age was independently associated with dementia. Dementia was strongly linked to the severity of the clinical‐functional frailty presented by the elderly.

Dementia is a priority public health issue due to its high prevalence worldwide and its economic, social, and health impact. However, there are few reports in Mexico based on formal tests and with a clinical approach based on the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). This study estimates the prevalence of the main types of dementia among elderly people living in the community in Mexico City. A population-based, two-step study was conducted, including 6,204 elderly individuals aged 60 or above with in-home assessment. All participants were screened for cognitive impairment; those who presented some cognitive problem underwent a standardized neurological examination. Each diagnosis was based on the criteria for dementia in the DSM-5, and the final consensus diagnosis of dementia was determined by an expert panel. The global estimated prevalence of dementia in the Mexican population was 7.8% met the criteria for Alzheimer's disease, 4.3% for vascular dementia, and 2.1% for mixed dementia. The prevalence of dementia was higher in women than in men (15.3% versus 12.5%, respectively). These results provide evidence to propose strategies for Latin American countries where dementia represents a challenge due to the heterogeneity of the populations and socioeconomic disparities, requiring early diagnosis and at the first levels of care.

Introduction: Dementia is a major cause of morbidity and dependence. The number of elderly individuals living with dementia worldwide is expected to rise up to 131 million by 2050. The Middle East and North Africa (MENA) is estimated to be one of the highest prevalence regions. However, there are limited numbers of studies in the region, especially on the primary care level. This study aims to determine the prevalence of dementia and identify the most important modifiable risk factors in our sample. Methods: A cross-sectional study design was used utilizing the non-probability convenience sampling technique. A questionnaire including demographic data, the Arabic version of the Patient Health Questionnaire (PHQ9) to screen for depression, and the Arabic version of the eight-item Alzheimer's Dementia (AD8) to screen for dementia, were administered to participants recruited from six primary healthcare centers in Riyadh city, Saudi Arabia. Results: This study found the prevalence of dementia to be 16% and 11% assuming cutoff points of 3 and 4, respectively, using the Arabic version of AD8, with depression and dyslipidemia as important modifiable risk factors for dementia in our sample. Conclusion: Primary healthcare professionals should be aware of the important modifiable risk factors such as dyslipidemia and depression in the population to be able to develop strategies for early detection and slowing down the progression of dementia. Further research to identify other modifiable risk factors in the population is recommended.

We investigated the prevalence of dementia and the apolipoprotein E (APOE) genotype distribution in the elderly of Buttapietra, a village near Verona, Italy. All residents over the age of 74 (n = 238), including those who were institutionalized, were studied using a direct-contact, single-phase design. The overall prevalence of dementia, clinically defined by DSM-III-R criteria, was 15.8 cases per 100 population, with age-specific figures increasing steeply with advancing age in both sexes. Alzheimer’s disease (AD) was the most frequent dementing disorder (43%). APOE genotyping was determined after DNA amplification by restriction isotyping. We found that the Ε4 allele and the Ε3/Ε4 genotype were associated with all types of dementia, although only the association of Ε3/Ε4 with AD reached statistical significance (odds ratio 4.5, 95% confidence interval 1.3–16.1). However, as reported in other Mediterranean countries, the frequency of the Ε4 allele in our population was low (8.9%), suggesting that the population-attributable risk for AD, at least for elderly individuals (≧75 years), could be small.

BackgroundThe number of people affected by dementia in Canada is anticipated to increase significantly in coming years. The province of Alberta is expected to have the largest relative increase in the number of people affected by dementia among all provinces in Canada. We determined the prevalence and incidence of diagnosed all‐cause dementia in Alberta, Canada between 2014 and 2022 using population‐based health data.MethodsPopulation‐based administrative health data were used to identify all individuals ages 65 years and older who were diagnosed with dementia between 2014 and 2022 in Alberta, Canada. A validated case ascertainment algorithm was used to identify cases of dementia. The prevalence of all‐cause dementia was reported for all individuals on April 1, of each year. Annual numbers of incident cases of dementia were reported on April 1 for each year using individuals newly diagnosed with dementia in the preceding year.ResultsThe overall prevalence of dementia in Alberta increased from 30,050 in 2014 to 43,802 in 2022 (45% relative increase). The number of incident cases of dementia increased from 6,884 individuals in 2014 to 8,741 in 2022 (27% relative increase). The incidence rate of dementia declined during this time period from 1.48/100 person years in 2014 to 1.37/100 person years in 2022 (p <0.001).ConclusionThe number of prevalent and incident cases of dementia increased significantly in Alberta between 2014 and 2022 although the incidence rate of dementia is decreasing during this time. This information has important implications for the planning supports and services for this population.