Risk of Seizures in First Degree Relatives of Probands with Epilepsy

Objective: To determine the risk of seizures in first degree relatives of epileptic patients. To relate the risk to several clinical characteristics in the probands. Such information is useful for genetic counselling. Methods: A prospective case-control study of 648 FDR of 88 probands attending the neurology out-patient clinic of a tertiary hospital in Lagos, Nigeria, and 308 FDR of 44 age and sex-matched controls was carried out. History of seizures in all FDR was sought using a survey questionnaire either directly filled by the FDR, probands or both. The risk of seizures in FDR was related to some clinical variables in the probands. Results: Overall risk of seizures was slightly but insignificantly higher (3.6%) in FDR of probands with epilepsy compared to controls (2.3%) (chitest; p > 0.05). Risk of seizures was highest in offspring of probands (4.3%), and FDR of female probands (4.0% compared to 3.1% in males), probands with seizure onset below 10 years (5.1% compared to 3.1% >10years) and probands with complex partial seizures (4.9% compared to 3.9% for generalized tonic-clonic seizures). The differences did not however reach statistical significance in comparison to the control group (chitest; p > 0.05). Conclusion: The risk of seizures in FDR of Nigerian probands with epilepsy has a similar profile with that in other environments such as Europe and North America in that it is marginally higher but not significantly different from the risk in the normal population. Nig. Qt. J. Hosp. Med. Vol.12(1-4) 2002: 66-7