ABSTRACT
Background: The number of people with multiple sclerosis (MS) globally has increased from 2.3 million in 2013 to 2.8 million in 2020. However, MS and other demyelinating diseases are reported to be very rare in sub-Saharan Africa. Objective(s): We aimed to describe demographic and clinical characteristics of the first cohort of patients with MS and neuromyelitis optica (NMO) from Zambia and one of the first such cohorts from the sub-Saharan African region. Method(s): Adults diagnosed with either MS, NMO, NMO spectrum disorder (NMOSD), or clinically isolated syndrome (CIS) at the neurology outpatient clinic at the University Teaching Hospital in Lusaka, Zambia, the only neurology clinic in the country, were eligible to participate. Participants were enrolled from October 2019 through February 2022 with significant interruptions due to Covid- 19. An MS-trained nurse administered structured questionnaires regarding sociodemographic characteristics, and each participant also underwent a comprehensive neurological history and examination by a neurologist. Finally, plasma 25-hydroxyvitamin D levels were obtained. For analysis, the cohort was dichotimized into a MS/CIS disease group and NMO/NMOSD disease group. Descriptive statistics of the cohort are presented and compared between both groups. Result(s): Amongst the 34 participants, mean age was 36 + 9 years, 65% (n=22) were female, 90% were Black-African, 10% were of Southeast Asian decent, 50% had MS/CIS, and 50% had NMO/NMOSD. The average age was 34 + 11 years in the MS/CIS group and 37 + 7 years in the NMO/NMOSD group (p=0.28). Females constituted 65% (n=11) of both disease groups. Median time to diagnosis was 242 days (interquartile range IQR: 91-974) and did not differ significantly between the groups. The majority (82%) of the NMO/NMOSD group presented with bilateral optic neuritis. Among the MS/CIS group, median EDSS was 4 (IQR: 2.25-4.25), median Disease Steps were 2 (IQR: 1-2), and 59% (n=10) had an abnormal gait at enrollment. Median 25-hydroxyvitamin D level was 29 (IQR: 24-46) ng/mL in the overall cohort but did not differ by disease group or supplementation status. Conclusion(s): In this sub-Saharan African cohort of adults with demyelinating diseases, MS and NMO were equally prevalent. Furthermore, delays in diagnosis resulted in high levels of disability in both groups. This demonstrates the need for more research and funding towards demyelinating diseases in sub-Saharan Africa.