Risk factors for dementia in a senegalese elderly population aged 65 years and over

Prevalence of suspected dementia in a sample of adults living in Kinshasa-Democratic Republic of the Congo

BACKGROUND

The prevalence of dementia in Sub-Saharan Africa, particularly in French-speaking countries, has received limited attention. This study investigates the prevalence and risk factors of suspected dementia in elderly adults in Kinshasa, Democratic Republic of the Congo (DRC).

METHODS

A community-based sample of 355 individuals over 65 years old was selected using multistage probability sampling in Kinshasa. Participants were screened using the Community Screening Instrument for Dementia, Alzheimer's Questionnaire, Geriatric Depression Scale, Beck Anxiety Inventory, and Individual Fragility Questionnaire, followed by clinical interview and neurological examination. Suspected dementia diagnoses were made based on the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria including significant cognitive and functional impairments. Prevalence and odds ratios (ORs) with 95% confidence interval (CI) were calculated using, respectively, regression and logistic regression.

RESULTS

Among 355 participants (mean age 74, SD = 7; 51% male), the crude prevalence of suspected dementia was 6.2% (9.0% in women and 3.8% in men). Female sex was a significant factor associated with suspected dementia [OR = 2.81, 95% CI (1.08-7.41)]. The prevalence of dementia increased with age (14.0% after 75 years and 23.1% after 85 years), with age being significantly associated with suspected dementia [OR = 5.42, 95% CI (2.86-10.28)]. Greater education was associated with a lower prevalence of suspected dementia [OR = 2.36, 95% CI (2.14-2.94), comparing those with ≥7.3 years of education to those with <7.3 years of education]. Other factors associated with the prevalence of suspected dementia included being widowed (OR = 1.66, 95% CI (1.05-2.61), being retired or semi-retired (OR = 3.25, 95% CI (1.50-7.03)], a diagnosis of anxiety [OR = 2.56, 95% CI (1.05-6.13)], and death of a spouse or a relative after age 65 [OR = 1.73, 95% CI (1.58-1.92)]. In contrast, depression [OR = 1.92, 95% CI (0.81-4.57)], hypertension [OR = 1.16, 95% CI (0.79-1.71)], body mass index (BMI) [OR = 1.06, 95% CI (0.40-2.79)], and alcohol consumption [OR = 0.83, 95% CI (0.19-3.58)] were not significantly associated with suspected dementia.

CONCLUSIONS

This study found a prevalence of suspected dementia in Kinshasa/DRC similar to other developing countries and Central African countries. Reported risk factors provide information to identify high-risk individuals and develop preventive strategies in this setting.

Dementia Prevalence and Risk Factors: Data From Rural Tanzania

OBJECTIVES

The burden of dementia is increasing in sub-Saharan Africa (SSA), but there are limited epidemiological data on dementia in SSA. This study investigated the prevalence and associations of dementia in older adults (less than 60 y) attending the outpatient department of Mount Meru Hospital in Tanzania.

METHODS

This one-phase cross-sectional study screened a sample using the Identification of Dementia in Elderly Africans (IDEA) cognitive screening tool. Those that screened as having possible and probable dementia were further assessed, and diagnosis of dementia was made according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Demographic and risk factor data were collected.

RESULTS

Within those screened, 57/1141 (5.0%) (95% CI: 3.7-6.3) had dementia. Female sex [odds ratio (OR)=2.778, 95% CI: 1.074-7.189], having never attended school (OR=6.088, 95% CI: 1.360-27.256), alcohol (U/wk) (OR=1.080, 95% CI: 1.016-1.149), uncorrected visual impairment (OR=4.260, 95% CI: 1.623-11.180), body mass index <18.5 kg/m 2 (OR=6.588, 95% CI: 2.089-20.775), and stroke (OR=15.790, 95% CI: 3.48-74.475) were found to be significantly, independently associated with dementia.

CONCLUSIONS

The prevalence of dementia in this population is similar to a recent community-based rate in Tanzania and lower than a hospital-based rate in Senegal. This is the first time the association between visual impairment and dementia has been reported in SSA. Other associations are in keeping with previous literature.

Cognitive functioning and prevalence of seizures among older persons in Uganda: A hospital-based, cross-sectional study

There is limited data on the prevalence of seizures and dementia among older persons in Uganda. We evaluated cognitive functioning, and the prevalence and factors associated with seizures among older persons attending an outpatient medical clinic in Uganda. We randomly selected older adults (60 years and above) attending Kiruddu National Referral Hospital medical outpatient clinics between October 2020 and March 2021. We excluded individuals with a history of head injury, brain tumors, mental retardation, co-morbidity with HIV and patients who have had recent brain surgery. Cognitive functioning was assessed using the Identification for Dementia in Elderly Africans (IDEA) tool. We enrolled 407 participants, with a median (inter-quartile range) age of 67 (64-73) years. Majority were female (n = 292, 71.7%). The prevalence of seizure was 1.5% (95% confidence interval [CI]: 0.7-3.3). All 6 participants reported generalized tonic-clonic seizure type. Self-reported seizure was associated with being female (adjusted prevalence ratio [aPR]: 0.79, 95%CI: 0. 67-0.93, P = .02) and residing in Mukono district (aPR: 17.26, 95%CI: 1.64-181.55, P = .018). Overall, 114 (28.1%) participants had cognitive deficit; 9 (2.2%) dementia and 105 (25.9%) impaired cognition. Cognitive deficit was independently associated with female gender (aPR: 0.61, 95%CI: 0.44-0.85, P = .003), formal employment (aPR: 0.53, 95%CI: 0.35-0.81, P = .003), age 70-74 (aPR: 1.69, 95%CI: 1.00-2.86, P = .049), and ≥ 75 years (aPR: 2.81, 95%CI: 1.71-4.61, P = .001). Prevalence of seizures among participants with cognitive deficit was 5.3% (6/114). Among older persons attending a medical clinic in Uganda, almost one-third had cognitive deficit with seizure prevalence being higher among these individuals.

Dementia in Africa: Current evidence, knowledge gaps, and future directions

In tandem with the ever-increasing aging population in low and middle-income countries, the burden of dementia is rising on the African continent. Dementia prevalence varies from 2.3% to 20.0% and incidence rates are 13.3 per 1000 person-years with increasing mortality in parts of rapidly transforming Africa. Differences in nutrition, cardiovascular factors, comorbidities, infections, mortality, and detection likely contribute to lower incidence. Alzheimer's disease, vascular dementia, and human immunodeficiency virus/acquired immunodeficiency syndrome-associated neurocognitive disorders are the most common dementia subtypes. Comprehensive longitudinal studies with robust methodology and regional coverage would provide more reliable information. The apolipoprotein E (APOE) ε4 allele is most studied but has shown differential effects within African ancestry compared to Caucasian. More candidate gene and genome-wide association studies are needed to relate to dementia phenotypes. Validated culture-sensitive cognitive tools not influenced by education and language differences are critically needed for implementation across multidisciplinary groupings such as the proposed African Dementia Consortium.

Epilepsy in Older People in Sub-Saharan Africa: A Systematic Review

BACKGROUND

Over one-fourth of new onset epilepsy occurs after age 60. However, the burden of epilepsy and other seizure disorders among this special population in Africa is largely unknown, despite a growingnumber of elderly persons on the continent. This study aimed to assess the prevalence and risk factors for epilepsy among persons aged 60 years or older in Africa.

METHODS

We conducted a systematic review by searching MEDLINE (via) and EMBASE databases from inception to 30th October 2020. Primary researches reporting prevalence or incidence of seizures or epilepsy in older persons (≥60 years) were included. Review articles were excluded.

RESULTS

We retrieved 107 citations from which 4 studies, recruiting 10, 334 participants were eligible. The studies were conducted between 1999 and 2018 and published between 2005 and 2019. Two of the studies were conducted in the West African countries of Niger and Senegal; meanwhile, the remaining 2 were conducted in East African country of Tanzania. Regarding study design, three were either hospital-based or community-based cross-sectional studies. Meanwhile, 1 was a retrospective hospital-based study. Of the 10,334 participants, 81 (0.78%) had a seizure disorder. The prevalence of seizure ranged from 0.02% to 3.2%.

CONCLUSION

There are limited data on the prevalence of epilepsy in older persons in older adults in most countries in sub-Saharan Africa. Epilepsy among the older adults remains a challenge in Africa and more information is needed to understand the burden to improve care.

Dominant and Modifiable Risk Factors for Dementia in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

Background: Sub-Saharan Africa (SSA) is projected to have a rapid increase in the number of people living with dementia by 2050. Yet, there is currently no robust evidence on the risk factors for dementia in the sub-region that could inform context specific interventions. Methods: We conducted a systematic review and meta-analysis of observational studies to determine the dominant and modifiable risk factors for dementia in SSA. We searched MEDLINE, EMBASE, PsychINFO, and African Journals Online using keywords for dementia and Alzheimer's disease as well as the.mp operator for all 47 SSA countries or regions. We included peer-reviewed original studies with epidemiological designs, conducted random effect meta-analysis and determined the dominant and modifiable risk factors for dementia using the inverse of variance method. Results: A total of 44 studies out of 2,848 met criteria for syntheses. The pooled annual incidence of dementia from 5,200 cohort risk years was 2.0% [(95% Confidence Interval (CI) = 1.0-4.0%)]. The pooled prevalence was 5.0% (95% CI = 2.0-7.0%). Older age was the dominant risk factor for both prevalent [(Standard error (S.E = 0.3, weight = 25.2%)] and incident dementia (S.E = 0.02, weight = 95.8%), while low educational attainment (S.E = 0.19, weight = 32.6%) and poor predementia cognitive functioning at baseline (S.E = 0.2, weight = 20.5%) were the best ranked modifiable risk factor for incident dementia. Conclusion: Low formal educational attainment which, in SSA, may represent a stable index of low socioeconomic position and health disadvantage over the life course, was the most prominent modifiable risk factor for incident dementia. Findings have implications for deliberate policies targeted at access to education across the life course as a primary prevention strategy against dementia in SSA.

Prevalence and correlates of Alzheimer's disease and related dementias in rural Uganda: cross-sectional, population-based study

Background

There is a paucity of data on the prevalence and correlates of Alzheimer’s disease and related dementias in sub-Saharan Africa. The aim of the study was to estimate the prevalence and correlates of Alzheimer’s disease and related dementias in rural Uganda.

Methods

We conducted a cross-sectional, population-based study in a rural region of southwestern Uganda. The Brief Community Screening Instrument for Dementia was administered to a multi-stage area probability sample of 400 people aged 60 years and over. Multivariable logistic regression was used to estimate correlates of probable dementia.

Results

Overall, 80 (20%) of the sample screened positive for dementia. On multivariable regression, we estimated the following correlates of probable dementia: age (adjusted odds ratio [AOR], 1.02 per year; 95% confidence interval [CI], 1.10–1.03, p<0.001), having some formal education (AOR, 0.57; 95% CI, 0.41–0.81, p = 0.001), exercise (AOR, 0.44; 95% CI, 0.27–0.72, p = 0.001), and having a ventilated kitchen (AOR, 0.43; (95% CI, 0.24–0.77, p = 0.001).

Conclusions

In this population-based sample of older-age adults in rural Uganda, nearly one-fifth screened positive for dementia.

Alcohol and Dementia - What is the Link? A Systematic Review

BACKGROUND

Dementia is a globally increasing health issue and since no cure is currently available, prevention is crucial. The consumption of alcohol is a controversially discussed risk factor for dementia. While many previously published epidemiological studies reported a risk reduction by light to moderate alcohol consumption, there is no persuasive model of an underlying biochemical mechanism. The purpose of this article is to review current models on alcohol neurotoxicity and dementia and to analyze and compare studies focusing on the epidemiological link between alcohol consumption and the risk of dementia.

METHODS

The electronic database Pubmed was searched for studies published between 1994 and 2019 concerning the topic.

RESULTS

Available epidemiological studies are not sufficient to verify a protective effect of alcohol on dementia development.

An Overview of the Cardiorespiratory Hypothesis and Its Potential Contribution to the Care of Neurodegenerative Disease in Africa

One hypothesis that could explain the beneficial effects of physical exercise on cognitive function is the cardiorespiratory hypothesis. This hypothesis proposes that improved cognitive functioning may be in part a result of the physiological processes that occur after physical exercise such as: Increased cerebral perfusion and regional cerebral blood flow. These processes ensure increased oxygenation and glucose transportation to the brain, which together can improve cognitive function. The objective of this narrative review is to examine the contribution of this hypothesis in the care of African older adults with neurodegenerative conditions (i.e., dementia (Alzheimer’s disease)) or with mild cognitive impairments. Although studies in developed countries have examined people of African descent (i.e., with African Americans), only the limited findings presented in this review reflect how these conditions are also important for the African continent. This review revealed that no studies have examined the effects of cardiorespiratory fitness on neurodegenerative disease in Africa. African nations, like many other developing countries, have an aging population that is growing and will face an increased risk of neurodegenerative declines. It is therefore imperative that new research projects be developed to explore the role of the cardiorespiratory fitness in neurodegenerative disease prevention in African nations.

Impacts of Illiteracy on the Risk of Dementia: A Global Health Perspective

Despite its significance as a contributing factor for late-life dementia risk, illiteracy is frequently underappreciated in the management of dementia. In this study, we estimated the proportion of dementia cases attributable to illiteracy using the population attributable fraction (PAF), and calculated to what extent the monetary cost of dementia could be saved in the future by reducing illiteracy from the South Korean, Latin American, South Asian/Middle Eastern, and African populations. We collected necessary data from the 2011 United Nations Human Development Report and prevalence studies conducted in these regions. Additional variables not included in the above sources were estimated using a logit model under a "trend scenario"-based assumption. Around 16% of the total number of dementia cases in South Korea in 2015 can be attributed to illiteracy, with this figure predicted to decline to around 2% by 2050. This translates to a saving in dementia care costs of approximately 52 billion USD, providing we are successful in theoretically eradicating illiteracy as of 2015, in the population aged 65 years or under. Likewise, reducing illiteracy to 50% in Latin America, South Asia/The Middle East, and Africa by 2050 could generate further cost savings of between 71 and 244 billion, 13 and 94 billion, and 17 and 78 billion USD, respectively. Even public policies aimed solely at reducing illiteracy in the childhood, adolescent, or middle-aged population could potentially have a role in the primary prevention of dementia. Moving forward, governments will need to address this issue in a purposeful and systematic manner.

Outcome of childhood-onset epilepsy from adolescence to adulthood: Transition issues

This is the second of three papers that summarize the second symposium on Transition in Epilepsies held in Paris in June 2016. This paper addresses the outcome for some particularly challenging childhood-onset epileptic disorders with the goal of recommending the best approach to transition. We have grouped these disorders in five categories with a few examples for each. The first group includes disorders presenting in childhood that may have late- or adult-onset epilepsy (metabolic and mitochondrial disorders). The second group includes disorders with changing problems in adulthood (tuberous sclerosis complex, Rett syndrome, Dravet syndrome, and autism). A third group includes epilepsies that change with age (Childhood Absence Epilepsy, Juvenile Myoclonic Epilepsy, West Syndrome, and Lennox-Gastaut syndrome). A fourth group consists of epilepsies that vary in symptoms and severity depending on the age of onset (autoimmune encephalitis, Rasmussen's syndrome). A fifth group has epilepsy from structural causes that are less likely to evolve in adulthood. Finally we have included a discussion about the risk of later adulthood cerebrovascular disease and dementia following childhood-onset epilepsy. A detailed knowledge of each of these disorders should assist the process of transition to be certain that attention is paid to the most important age-related symptoms and concerns.

Epidemiology of Dementia among the Elderly in Sub-Saharan Africa

Objectives. To review epidemiologic studies on the prevalence, incidence, and risk factors of dementia in sub-Saharan Africa (SSA). Methods. A MEDLINE search (from January 1992 to December 31, 2013) of epidemiologic studies, with no language restriction, was conducted using the keywords “dementia” or “Alzheimer's” and “Africa.” We selected for review population and hospital-based studies that reported the prevalence, incidence, or risk factors of dementia in SSA in people aged 60 years and above. References of selected articles were reviewed to identify additional relevant articles that met our selection criteria. Results. Of a total of 522 articles, 41 were selected and reviewed. The reported prevalence of dementia in SSA varied widely (range: 2.29%–21.60%); Alzheimer's disease was the most prevalent type of dementia. Only two studies conducted in Nigeria reported incidence data. Major risk factors identified include older age, female gender, cardiovascular disease, and illiteracy. Conclusion. Data on the epidemiology of dementia in SSA is limited. While earlier studies reported a lower prevalence of dementia in older persons, recent studies have put these findings into question suggesting that dementia prevalence rates in SSA in fact parallel data from Western countries.

Epidemiology of neurodegenerative diseases in sub-Saharan Africa: a systematic review

BACKGROUND

Sub-Saharan African (SSA) countries are experiencing rapid transitions with increased life expectancy. As a result the burden of age-related conditions such as neurodegenerative diseases might be increasing. We conducted a systematic review of published studies on common neurodegenerative diseases, and HIV-related neurocognitive impairment in SSA, in order to identify research gaps and inform prevention and control solutions.

METHODS

We searched MEDLINE via PubMed, 'Banque de Données de Santé Publique' and the database of the 'Institut d'Epidemiologie Neurologique et de Neurologie Tropicale' from inception to February 2013 for published original studies from SSA on neurodegenerative diseases and HIV-related neurocognitive impairment. Screening and data extraction were conducted by two investigators. Bibliographies and citations of eligible studies were investigated.

RESULTS

In all 144 publications reporting on dementia (n = 49 publications, mainly Alzheimer disease), Parkinsonism (PD, n = 20), HIV-related neurocognitive impairment (n = 47), Huntington disease (HD, n = 19), amyotrophic lateral sclerosis (ALS, n = 15), cerebellar degeneration (n = 4) and Lewy body dementia (n = 1). Of these studies, largely based on prevalent cases from retrospective data on urban populations, half originated from Nigeria and South Africa. The prevalence of dementia (Alzheimer disease) varied between <1% and 10.1% (0.7% and 5.6%) in population-based studies and from <1% to 47.8% in hospital-based studies. Incidence of dementia (Alzheimer disease) ranged from 8.7 to 21.8/1000/year (9.5 to 11.1), and major risk factors were advanced age and female sex. HIV-related neurocognitive impairment's prevalence (all from hospital-based studies) ranged from <1% to 80%. Population-based prevalence of PD and ALS varied from 10 to 235/100,000, and from 5 to 15/100,000 respectively while that for Huntington disease was 3.5/100,000. Equivalent figures for hospital based studies were the following: PD (0.41 to 7.2%), ALS (0.2 to 8.0/1000), and HD (0.2/100,000 to 46.0/100,000).

CONCLUSIONS

The body of literature on neurodegenerative disorders in SSA is large with regard to dementia and HIV-related neurocognitive disorders but limited for other neurodegenerative disorders. Shortcomings include few population-based studies, heterogeneous diagnostic criteria and uneven representation of countries on the continent. There are important knowledge gaps that need urgent action, in order to prepare the sub-continent for the anticipated local surge in neurodegenerative diseases.

Dementia care in public health in Brazil and the world: A systematic review

OBJECTIVE

This study aimed to identify in the recent scientific literature, information on health care provided to people with dementia, dementia costs and its resource implications for public health.

METHODS

This was a systematic review of the literature in which the articles were consulted from the databases PubMed/MEDLINE, LILACS and SciELO. The review sample consisted of 45 articles.

RESULTS

Examination of the studies identified the current scenario of dementia in relation to public health and public policy in Brazil and the world. The analyzed studies revealed key information on aspects of dementia in the world. There was consensus on the high prevalence of the syndrome and on the significant cost of health care and public policy for assisting the elderly with dementia.

CONCLUSION

The importance of planning and implementing new public policies was recognized, since these are essential for the organization and management of health services and directly influence the country's ability to provide health care for people with dementia.