An investigation into the relationship between first-degree relatives of bipolar affective disorder and (idiopathic) epilepsy in a sub-Saharan African population

Abstract

ObjectivePhenomenological, neuro-biological and pharmacological investigations linked bipolar affective disorders with epilepsy. Similarly, a large community-based epidemiological study of epileptic patients reported that 12% of the participants had bipolar symptoms, a rate 7× higher than in control. Bipolar and epileptic disorders are epiphenomena of an underlying genetic susceptibility. This study aimed to determine the relationship between first-degree relatives of bipolar and epileptic patients in a sub-Saharan African population. MethodIn this case-control study, we used a socio-demographic and clinical variables questionnaire to assess random convenient samples of 50 control, 40 and 60 first-degree relatives of bipolar and epileptic patients, respectively at Federal Neuro-psychiatric Hospital (FNPH), Maiduguri. Relatives of epileptic patients and the control completed the mood disorder questionnaire (MDQ). Two consultant psychiatrists made the diagnosis of epilepsy using the ILAE criteria, in relatives of bipolar patients and the control. Participants in both groups had no EEG.We analysed the data obtained, using EPI-info 7 to report averages and associations between categorical variables with Chi-square test, and analysis of variance (ANOVA) for parametric data(statistical significance set at p=0.5, two-tailed). ResultsThe rate of epilepsy among relatives of bipolar disorder compared with control was 15.2% vs. 2.0% (χ2=46.08, p<0.001), and that of bipolar among relatives of epileptics compared with control was 14.5% vs. 2.1% (χ2=31.2, p<0.001). Educational status showed significant relationship across two groups (χ2=24.19, p=0.0001). Using ANOVA, age showed significant relationship among relatives of bipolar and epileptic patients (F=5.769, p=0.0039). ConclusionDespite its limitations, this preliminary study contributes to literature on the relationship between epilepsy and bipolar affective disorder in sub-Saharan Africa.