What Non-Genetic Parkinson’s Disease Risk Factors are Africans Exposed To? A Scoping Review

Background

Parkinson's disease (PD) is recognized as one of the most prevalent neurological disorders globally [1]. Despite its widespread incidence, there remains a significant gap in the understanding of PD, particularly concerning its risk factors [2]. We set out to catalogue the risk factors patients with Parkinson’s Disease (PD) are exposed to.

The Transforming Parkinson’s Care in Africa (TraPCAf) initiative is a collaborative research effort, which aims to address various facets of PD [3]. Multiple risk factors for PD have been established across various regions of the world. Newer research areas, such as the human microbiome, have also started to show promising insights into predisposition for multiple conditions. Africa is a continent of rapid growth in multiple sectors including agriculture and mining which may be important with respect to environmental risk factors [4,5]

Methods

172 papers were identified that related to PD in Africa. 28 studies met our inclusion criteria, focusing on the prevalence and impact of various risk factors for PD within the African context. The primary risk factors identified were pesticide exposure, heavy metal exposure, comorbidities such as Diabetes Mellitus (DM), and genetic and microbiome-related factors.

Results

The findings suggest a concerning trend: while certain regions, such as Southern Africa, have seen more extensive research into these risk factors, there remains a stark lack of data from West, Central, and East Africa.

Pesticides emerged as a significant contributor to the occurrence of PD. Agricultural practices, prevalent in many African countries, are associated with increased exposure to harmful chemicals. Heavy metal exposure- particularly from industries and mining, was identified as another critical risk factor. Comorbid conditions, such as DM, were also found to have a notable association with PD. Moreover, genetic predispositions and alterations in the microbiome were noted as influencing factors that could modify PD risk.

Conclusion

In conclusion, while this scoping review provides insights into the various risk factors associated with PD in Africa, a substantial portion of the continent remains underrepresented in the literature. Future efforts should focus on uncovering local environmental and lifestyle factors that contribute to PD.

Bibliography

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[2]- Dotchin, C., et al., The prevalence of Parkinson's disease in rural Tanzania. Mov Disord, 2008. 23(11): p. 1567-672.

[3]- Walker R, Fothergill-Misbah N, Kariuki S, Ojo O, Cilia R, Dekker MCJ, Agabi O, Akpalu A, Amod F, Breckons M, Cham M, Del Din S, Dotchin C, Guggsa S, Kwasa J, Mushi D, Nwaokorie FO, Park T, Rochester L, Rogathi J, Sarfo FS, Shalash A, Ternent L, Urasa S, Okubadejo N. Transforming Parkinson's Care in Africa (TraPCAf): protocol for a multimethodology National Institute for Health and Care Research Global Health Research Group project. BMC Neurol. 2023 Oct 19;23(1):373. doi: 10.1186/s12883-023-03414-0. PMID: 37858118; PMCID: PMC10585779.

[4]- Affairs, U.N.D.o.E.a.S., World Population Prospects 2022 Summary of Results. 2022, United Nations: Online.

[5]- Association, I.F. Africa Towards Sustainable Agriculture. 2021 [cited 2025 27/11]; Available from: https://www.africafertilizermap.com/.