Environmental Toxins as Causes of Brain Degeneration in Sub-Saharan Africa

  • Tom H. A. M. Olewe


Brain degeneration, especially Dementia is a complex human disease. The Alzheimer’s Association estimates that one in 10 persons over 65 and nearly half of those over 85 have Alzheimer’s disease. There is paucity of data on the prevalence of dementia in Sub-Saharan Africa. Available data suggests a general prevalence of dementia at 6.4 % in Tanzania and HIV related dementia at 31 % in Uganda. Despite the growing burden of dementia in low-income countries, there are few previous data on the prevalence, causes and risk factors of dementia in sub-Saharan Africa.

Therefore, it is important to identify protective and risk factors for dementia to prevent this disease at an early stage. Several factors are related to dementia, e.g. age, ethnicity, sex, genetic factors, physical activity, smoking, drug use, education level, alcohol consumption, body mass index, co-morbidity, and environmental factors. Due to paucity of Sub-Saharan African data, this review looks at studies done elsewhere to evaluate the association between environmental toxins and risk of dementia, especially Alzheimer’s and Parkinson’s diseases. We have examined whether evidence from previous studies on association between toxin environmental exposures and dementia is of sufficient strength to warrant specific recommendations for behavioral, lifestyle, or pharmaceutical interventions/modifications targeted to these endpoints. We also suggest future research directions for researchers in dementia-related fields in Sub-Saharan Africa.


Dementia Alzheimer’s disease Environmental toxins Sub-Saharan Africa 


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.School of Public Health, Kenyatta Hospital CampusUniversity of NairobiNairobiKenya

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