Long-term observation and mortality of children with nodding syndrome in western Uganda, 1994 - 2018.

ABSTRACT

PURPOSE: To assess long-term mortality and causes of death in children with nodding syndrome, an epileptic disorder of sub-Sahara Africa. METHODS: Ten children with nodding syndrome were followed over 24 years. The mortality rate was determined as the number of deaths per 1000 person-years of observation. The standard mortality ratio (SMR) was calculated as the number of observed deaths divided by the number of expected deaths in the general population. Patients were started on phenobarbital and treatment response was monitored during the first 20 months of follow-up. RESULTS: During an observation period of 89.8 person-years, eight patients had died, one patient was found alive, and one patient had been lost to follow-up. This corresponded to a mortality rate of 89.1 deaths per 1000 person-years and a SMR of 21.4 (95 % CI 6.6-36.2). Five deaths were related to status epilepticus, in two cases occurring after inadvertent drug withdrawal. All patients responded on phenobarbital with a reduction of seizure frequency but only four reached a seizure-free period of at least 6 months. CONCLUSIONS: This long-term follow-up demonstrated high mortality in patients with nodding syndrome. Anti-seizure treatment with phenobarbital was of moderate efficacy. Abrupt interruption of phenobarbital was found leading to seizure aggravation, status epilepticus, and death. Our findings point out the importance of securing continuity of treatment access once anti-seizure therapy is included in health services in resource-poor settings. More rigorous observations and controlled studies are needed to improve the therapeutic options for nodding syndrome.