Funding for this research was provided by:
National Institutes of Health (R21NS098862)
South African Medical Research Council (SATBBI)
National Institute of Neurological Disorders and Stroke (P50NS072187)
American Parkinson Disease Association (Udall Center)
Department of Science and Technology, Republic of South Africa (SATBBI)
South African National Research Foundation, (106052)
Lewy Body Dementia Association (Udall center)
South African National Research Foundation (NRF Innovation Postdoctoral Fellowship, Research funding)
Received: 5 March 2019
Accepted: 10 January 2020
First Online: 4 February 2020
Ethics approval and consent to participate
: All patients provided written informed consent to take part in the study. This study was submitted to and approved by the Health Research Ethics Committee of Stellenbosch University in South Africa (Approval reference numbers HREC 2002/C059, N16/04/041 and S16/08/151), as well as the Ethics and Research Committee of Obafemi Awolowo University Teaching Hospitals in Nigeria (Approval reference number ERC/2015/08/15).
: Not applicable.
: The authors declare that they have no competing interests.