Psychomotor function in children with epilepsy seen at a tertiary hospital in southern Nigeria: does treatment with anti-epileptic drugs have any effect?

Abstract

Background: Psychomotor slowing is more commonly reported in children with epilepsy (CWE) compared to healthy controls. The effect of anti-epileptic drug (AED) treatment on psychomotor abilities of CWE remains controversial. In Nigeria, psychomotor abilities of CWE are scarcely investigated and the impact of AEDs is not known. The present study sought to assess psychomotor performance of CWE compared to healthy controls and to determine any association with seizure characteristics and treatment. Method: A comparative cross-sectional study involving 160 children with idiopathic epilepsy and 80 controls aged 6–16 years. Psychomotor function was assessed using reaction times and tapping task of the Iron psychology computerised test battery. The criterion for impairment was fixed at two standard deviations (SD) worse than the mean of age-matched controls. The relationship between seizure variables and psychomotor function was assess with the one-way analysis of variance (ANOVA). Result: Fifty-nine (36.9%) CWE had impaired auditory reaction, 50 (31.3%) with impaired visual reaction and 11 (6.9%) had fine motor control impairment. There was no significant difference in psychomotor performance between CWE on AED and the newly diagnosed counterparts yet to start AED treatment (auditory reaction time—p = 0.226; visual reaction time—p = 0.349; tapping task—p = 0.818). AED treatment duration over 5 years was associated with better auditory reaction time (F = 4.631, p = 0.034) in CWE. Also, seizure onset before 5 years of age was associated with slower auditory reaction (F = 4.912, p = 0.028) and verbal reaction (F = 14.560, p < 0.001). Conclusion: Nigerian CWE perform less favourably on tests of psychomotor function than healthy controls. The performance of children on AED is not significantly different from those not on AED. Longer duration of AED treatment may result in psychomotor improvement in CWE. CWE should be closely monitored for psychomotor slowness so that deficits can be identified and appropriate interventions instituted.