| Summary: | Includes bibliographical references. === Motor neurone disease (MND) is a rare progressive neurodegenerative disorder in which selective degeneration of the motor neurones of the brain and spinal cord occurs. Progressive weakness of limb, bulbar and respiratory muscles eventually results in death. Most descriptive and epidemiological studies of MND have been performed in the industrialized countries of Europe and North America. We know very little about the incidence or prevalence of MND in Africa in general and South Africa in particular. However, anecdotal evidence based on observations by clinicians in the neurology and geriatric medical clinics at Groote Schuur Hospital suggest that the condition is not uncommonly seen, even in younger patients. Furthermore, many cases appear to originate from the West Coast area of the Western Cape. The proposed study aimed at describing the demographic and clinical characteristics of MND seen at Groote Schuur Hospital between 2005 and 2010. I hypothesized that disease duration, measured from age of onset of first symptoms to death, would be shorter in patients with bulbar-onset disease, in younger-onset disease, and in patients with higher CSF protein and blood creatine kinase levels at baseline. Furthermore, age of onset of the disease would be younger in familial compared with sporadic MND. I also hypothesized that smoking and certain occupational exposures might be risk factors for MND, that there would be a male preponderance of the disease, and that a disproportionate number of cases would come from the West Coast region. This was a retrospective study. I reviewed the clinical notes of cases of motor neurone disease and collected data relevant to the aims and hypotheses described above. I applied the El Escorial diagnostic criteria for MND to check the validity of the diagnoses. Mortality data were obtained through the Burden of Diseases Research Unit at the South African Medical Research Council. Forty eight patients were identified who met El Escorial criteria for the diagnosis of probable or definite MND. The median age of onset of the disease was 54 (IQR 47-63) and the mean duration of the disease from earliest symptoms to death was 2 years (IQR 1-3). These did not differ significantly between bulbar and limb-onset disease sub-types. There was a male preponderance of the disease (60%) and the majority of patients (60%) were smokers. African patients tended to have a younger age of onset. Occupations involving potential exposure to chemicals were disproportionately represented in the MND patients compared with the general population of the Western Cape. People from the West Coast region were not disproportionately represented in the patient population. Baseline CSF protein and serum creatine kinase levels were not associated with disease duration. The characteristics of MND cases seen at Groote Schuur Hospital between 2005 and 2010 are similar to those described in the world literature. Smoking and chemical exposure may be risk factors for the disease. There was no evidence of clustering of cases. This study will serve as the basis for future larger prospective studies on MND prevalence and aetiology in South Africa.
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