06.02.01. What is the estimated prevalence and incidence of dementia and the source of these estimates? | South Africa

06.02.01. What is the estimated prevalence and incidence of dementia and the source of these estimates? | South Africa

14 Aug 2022

The prevalence of dementia in Sub-Saharan Africa and South Africa has not been established conclusively (Kalaria et al., 2008; Kalula et al., 2010). From 2006 to 2050, South Africa’s older population is projected to increase from 3.3 to 6.4 million people (i.e., from 7% to 13% of the country’s population). The World Alzheimer’s report (2015) estimated that in 2015 about 186 000 people were living with dementia in South Africa, for which nearly 75% were women (Prince et al., 2016a). This number is expected to increase to 275 000 by 2030 (Prince et al., 2016a).

Although there are a few research studies on dementia in Sub-Saharan Africa, there is currently no nationally representative prevalence data available for South Africa (De Jager et al., 2017), with large scale community studies needed to confirm the prevalence of dementia (Ramlall et al., 2013). Existing research in South Africa has, for example, investigated the knowledge, attitudes, and beliefs about dementia in an urban Xhosa speaking community (Khonje et al., 2015), has examined the caregiving experiences for people with dementia (Gurayah, 2015; Pretorius et al., 2009), and has explored the consequences of stigma and related socio-cultural beliefs regarding people with dementia (Mkhonto & Hanssen, 2018).

Smaller studies have provided estimations of prevalence of dementia in South Africa. In 2010, a study examined all patients (N=305) at the UCT/Groote Schuur Hospital memory clinic between 2003 and 2008. The study evaluated the role and function of this facility in a resource-limited context and found that family members cared for 79% of patients (of which 74% lived with a spouse or an adult child), whereas 6% were institutionalised and 10% lived alone (Kalula et al., 2010). Depression was associated with 15% of patients and although Alzheimer’s disease was still the most common, when compared to other countries, vascular dementia (VaD) had a higher prevalence in South Africa (Kalula et al., 2010). This finding is suggestive of a high prevalence of stroke and associated risk factors that are not adequately addressed by the current health care systems (Kalula et al., 2010).

Working with the 10/66 Group, the University of the Free State examined an urban black community and reported a higher than expected 6% prevalence rate for persons 65 years and older (De Jager et al., 2015), while previous rates for Southern Africa have estimated 2.1% (Radebe, 2010). A smaller household study (N=100) in another urban, isiXhosa-speaking community in the Western Cape (Khayelitsha) found that 22% of households had a person over the age of 60 living in the area, of which 10% reported having more than one over the age of 60 (Khonje et al., 2015).

The first large screening study for dementia in South Africa was conducted in a low income, rural isiXhosa speaking population in the Amatole district, within the Eastern Cape province (De Jager et al., 2017). This community is characterised by subsistence farming of maize, with local diets supplemented with vegetables and occasional meat. A total of 1394 households were screened in 3 clinic catchment areas and estimated a prevalence of 11% for 65 years and older, indicating a higher than expected burden of dementia in South Africa, than the estimated 4% indicated by the World Alzheimer Report (2016) (De Jager et al., 2017). For those screened as dementia-positive participants, 69.8% were female and 69.8% had less than 7 years education. Dementia-positive participants were twice as likely to report any depressive symptoms and 17.1% of these reported on all 3 out of 3 (EURO-D questions) symptoms of depression.

References:

De Jager, C. A., Joska, J. A., Hoffman, M., Borochowitz, K. E., & Combrinck, M. I. (2015). Dementia in rural South Africa: A pressing need for epidemiological studies. South African Medical Journal, 105(3), 189–190. https://doi.org/10.7196/SAMJ.8904

De Jager, C.A., Msemburi, W., Pepper, K., & Combrinck, M. (2017). Dementia Prevalence in a Rural Region of South Africa: A Cross-Sectional Community Study. Journal of Alzheimer’s Disease, 60(3), 1087–1096. https://doi.org/10.3233/JAD-170325

Gurayah, T. (2015). Caregiving for people with dementia in a rural context in South Africa. South African Family Practice, 57(3), 194–197. https://doi.org/10.1080/20786190.2014.976946

Kalaria, R. N., Maestre, G. E., Arizaga, R., Friedland, R. P., Galasko, D., Hall, K., Luchsinger, J. A., Ogunniyi, A., Perry, E. K., Potocnik, F., Prince, M., Stewart, R., Wimo, A., Zhang, Z. X., & Antuono, P. (2008). Alzheimer’s disease and vascular dementia in developing countries: prevalence, management, and risk factors. The Lancet Neurology, 7(9), 812–826. https://doi.org/10.1016/S1474-4422(08)70169-8

Kalula, S. Z., Ferreira, M., Thomas, K. G. F., De Villiers, L., Joska, J. A., & Geffen, L. N. (2010). Profile and management of patients at a memory clinic. South African Medical Journal, 100(7), 449. https://doi.org/10.7196/SAMJ.3384

Khonje, V., Milligan, C., Yako, Y., Mabelane, M., Borochowitz, K. E., & Jager, C. A. De. (2015). Knowledge , Attitudes and Beliefs about Dementia in an Urban Xhosa-Speaking Community in South Africa. Advances in Alzheimer’s Disease, 4, 21–36. https://doi.org/10.4236/aad.2015.42004

Mkhonto, F., & Hanssen, I. (2018). When people with dementia are perceived as witches. Consequences for patients and nurse education in South Africa. Journal of Clinical Nursing, 27(1–2), e169–e176. https://doi.org/10.1111/jocn.13909

Pretorius, C., Walker, S., & Heyns, P. M. (2009). Sense of coherence amongst male caregivers in dementia: A South African perspective. Dementia, 8(1), 79–94. https://doi.org/10.1177/1471301208099046

Prince, Martin, Comas-Herrera, A., Knapp, M., Guerchet, M., & Karagiannidou, M. (2016a). World Alzheimer Report 2016: Improving healthcare for people living with dementia. In Alzheimer’s Disease International (ADI). https://doi.org/10.13140/RG.2.2.22580.04483

Ramlall, S., Chipps, J., Pillay, B., & Bhigjee, A. (2013). Mild cognitive impairment and dementia in a heterogeneous elderly population: Prevalence and risk profile. African Journal of Psychiatry (South Africa), 16(6), 456–465. https://doi.org/10.4314/ajpsy.v16i6.58