Identifying Frailty and its Outcomes in Older People in Rural Tanzania.

Background/Study Context: Interest in frailty is growing in low- and middle-income countries, due to demographic aging and resource limitations. However, there is a paucity of data on the nature of frailty in Africa. METHODS: The study collected frailty data from people aged 70 years and over living in six villages in the rural Hai District of northern Tanzania. At baseline, a limited data set was collected for 1198 people and a more comprehensive data set for a stratified sample of 296 people. A 40-item frailty index was constructed. Data regarding mortality and dependency were collected at 3-year follow-up. RESULTS: A higher frailty index score was significantly correlated with greater age, never having attended school, falls, mortality, and dependency in activities of daily living. Logistic regression modeling revealed functional disability and cognitive function to be significant independent predictors of the outcome "mortality or dependency." CONCLUSIONS: In resource-poor settings, brief frailty screening assessments may be a useful way of identifying those most in need of support.

Mild Cognitive Impairment in Rural Tanzania: Prevalence, Profile, and Outcomes at 4-Year Follow-up.

OBJECTIVE: Mild cognitive impairment (MCI) is recognized as a high-risk condition for conversion to dementia, although data on outcomes of MCI in sub-Saharan Africa are scarce. We investigated outcomes of MCI over a 4-year period in Tanzania and considered risk factors for conversion to dementia. METHODS: In a longitudinal cohort study in the Hai district, Tanzania, patients with MCI were identified during a two-phase prevalence study carried out in 2010. Of 1,198 people aged 70 years and over screened in phase I, a stratified sample of 296 were fully assessed in phase II. MCI was defined according to international consensus criteria. DSM-IV criteria were used for dementia diagnosis. Background demographic and risk factor data were collected, and neuropsychiatric symptoms were assessed using the neuropsychiatric inventory. Patients were followed-up in 2011, 2012 and 2014. RESULTS: Forty-six MCI patients were identified. After adjusting for stratification, the crude prevalence of MCI was 7.0% (95% CI: 3.6-10.4). Over a 4-year period, 15 patients (32.6%) progressed to dementia, 2 patients (4.3%) returned to normal cognition, 1 developed late-onset schizophrenia, 8 patients (17.4%) had stable MCI, 19 patients (41.3%) died, and 1 refused assessment. Age, sex, education levels, body mass index, hypertension, and comorbidity were not associated with progression to dementia. CONCLUSION: In this rural Tanzanian population, rates of conversion from MCI to DSM-IV dementia were similar to those reported in high-income countries. Over a third of all patients had died at the 4-year follow-up.

Development and Validation of the Identification and Intervention for Dementia in Elderly Africans (IDEA) Study Dementia Screening Instrument.

AIM: The aim of this project was to develop a dementia screening instrument for use in the hospital or community in populations with low levels of formal education. METHODS: A screening instrument was developed from retrospective data collected in a rural area of Tanzania in 2010. The community screening instrument for dementia was administered to over 95% of the population aged 70 years and older of 6 villages (n = 1198) in Hai district, Tanzania. Factor analysis, regression modeling, and Mokken scale analysis (MSA) were used to develop screening instruments from these data, which were then tested and refined during prospective fieldwork. RESULTS: A 5-item screening instrument with an area under the receiver-operating characteristic (AUROC) curve of 0.871, sensitivity of 91.7%, and specificity of 61.7% was developed using a combination of factor analysis and logistic regression modeling and had a higher AUROC (0.786) than a 7-item screening instrument developed using MSA. During prospective testing and refinement (n = 60), the 5-item instrument performed well (AUROC 0.867) and took an average of less than 10 minutes to administer. Its performance was improved by including a matchstick design item added to measure praxis, AUROC 0.888. CONCLUSIONS: The 6-item brief dementia screening instrument has acceptable properties and will be further tested and validated during future fieldwork. Although developed for use in sub-Saharan Africa, it may be of use in other world regions where the use of other cognitive screening instruments may result in bias due to low levels of formal education.

The prevalence of dementia in rural Tanzania: a cross-sectional community-based study.

OBJECTIVES: Despite the growing burden of dementia in low-income countries, there are few previous data on the prevalence of dementia in sub-Saharan Africa. The aim of this study was to estimate the prevalence of dementia in those who are 70 years and older in the rural Hai District of Tanzania. METHODS: This was a two-phase cross-sectional survey. Using census data, we screened individuals aged 70 years and older from six rural villages using the Community Screening Instrument for Dementia in Phase I. In Phase II, a stratified sample of those identified in Phase I were clinically assessed using the DSM-IV criteria. RESULTS: Of 1198 people who fulfilled the inclusion criteria, 184 screened positive for probable dementia, and 104 screened positive for possible dementia using the Community Screening Instrument for Dementia. During clinical assessment in Phase II, 78 cases of dementia were identified according to the DSM-IV criteria. The age-standardised prevalence of dementia was 6.4% (95% confidence interval: 4.9 to 7.9). Prevalence rates increased significantly with increasing age. CONCLUSIONS: The prevalence of dementia in this rural Tanzanian population is similar to that reported in high-income countries. Dementia is likely to become a significant health burden in this population as demographic transition continues. Further research on risk factors for dementia in sub-Saharan Africa is needed to inform policy makers and plan local health services.

The prevalence of disability in older people in Hai, Tanzania.

BACKGROUND: the World Health Organization estimates that more than one billion of the world's population are disabled. Disability is associated with increasing age and poverty, yet there are few reliable data regarding disability among the elderly in low-income countries. The aim of this study was to accurately document the prevalence of disability in those aged 70 years and over in a community-based setting in sub-Saharan Africa. METHODS: we performed a community-based study of people aged 70 years and over in Hai, Tanzania. Participants underwent disability assessment using the culturally non-specific Barthel index (BI), and also clinical assessment for neurological disorders and memory problems. RESULTS: in 2,232 participants, the age-adjusted prevalence of severe disability (BI<15) was 3.7% (95% CI: 2.9-4.5) and the age-adjusted prevalence of moderate disability (BI: 15-18) was 6.2% [95% confidence interval (CI): 5.2-7.2]. Increasing age, female gender, memory problems and the presence of neurological disorders were all independent predictors of the presence of disability. CONCLUSION: in this study, the average disability level was lower than seen in most high-income countries. This may reflect increased mortality from disabling disease in low-income countries. Disability is likely to increase as the population of low-income countries ages and disease survival improves.

The association between disability and cognitive impairment in an elderly Tanzanian population.

Cognitive impairment is thought to be a major cause of disability worldwide, though data from sub-Saharan Africa (SSA) are sparse. This study aimed to investigate the association between cognitive impairment and disability in a cohort of community-dwelling older adults living in Tanzania. The study cohort of 296 people aged 70years and over was recruited as part of a dementia prevalence study. Subjects were diagnosed as having dementia or mild cognitive impairment according to the DSM-IV criteria. Disability level was assessed according to the WHO Disability Assessment Schedule, version 2.0 (WHODAS). A higher WHODAS score indicates greater disability. The median WHODAS in the background population was 25.0; in those with dementia and in those with mild cognitive impairment, 72 of 78 (92.3%) and 41 of 46 (89.1%), respectively, had a WHODAS score above this level. The presence of dementia, mild cognitive impairment, hearing impairment, being unable to walk without an aid and not having attended school were independent predictors of having a WHODAS score above 25.0, though age and gender were not. In summary, cognitive impairment is a significant predictor of disability in elderly Tanzanians. Screening for early signs of cognitive decline would allow management strategies to be put in place that may reduce the associated disability burden.

Dementia prevalence estimates in sub-Saharan Africa: comparison of two diagnostic criteria.

BACKGROUND: We have previously reported the prevalence of dementia in older adults living in the rural Hai district of Tanzania according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria. The aim of this study was to compare prevalence rates using the DSM-IV criteria with those obtained using the 10/66 diagnostic criteria, which is specifically designed for use in low- and middle-income countries. METHODS: In phase I, 1,198 people aged 70 and older were screened for dementia. A stratified sample of 296 was then clinically assessed for dementia according to the DSM-IV criteria. In addition, data were collected according to the protocol of the 10/66 Dementia Research Group, which allowed a separate diagnosis of dementia according to these criteria to be established. RESULTS: The age-standardised prevalence of clinical DSM-IV dementia was 6.4% (95% confidence interval [CI] 4.9-7.9%) and of '10/66 dementia' was 21.6% (95% CI 17.5-25.7%). Education was a significant predictor of '10/66 dementia', but not of DSM-IV dementia. CONCLUSIONS: There are large discrepancies in dementia prevalence rates depending on which diagnostic system is used. In rural sub-Saharan Africa, it is not clear whether the association between education and dementia using the 10/66 criteria is a genuine effect or the result of an educational bias within the diagnostic instrument. Despite its possible flaws, the DSM-IV criteria represent an international standard for dementia diagnosis. The 10/66 diagnostic criteria may be more appropriate when identification of early and mild cognitive impairment is required.