Factors predicting the risk of seizure relapse after antiepilepsy drug withdrawal in childhood epilepsy / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the factors associated with seizure relapse after antiepilepsy drug (AED) withdrawal in childhood epilepsy.Methods A retrospective analysis was conducted in epileptic children of Hunan Children's Hospital from Jan.2003 to Jan.2011.Among those with anti-epileptic therapy for seizure-free period over 2 years,the patients who relapsed after withdrawal were followed up through outpatient clinic visits and/or by telephone interviews for at least 2 years.Results Of the 127 cases of children enrolled in this study,28 patients(22.05％) relapsed [male12/59 cases (20.34％) and female16/68 cases (23.53％)].Cumulative relapse rates were 18.18％ (8/44 cases) in infancy,15.79％ (6/38 cases) in toddlers,23.53％ (8/34 cases) in preschool children,and 54.55％ (6/11 cases)in school age group.Of the patients who relapsed,generalized seizure occurred in 12/87 cases (13.79％),partial seizure in 16/40 cases(40.00％).According to seizure frequency between the first seizure and AED administration,3 cases(6.25％) relapsed among 48 cases of seizure frequency ＜ 5 times,13 cases(24.07％) relapsed among 54 cases of seizure frequency 5 to 10 times,and 12 cases(48.00％) relapsed among 25 cases of seizure frequency more than 10 times.Relapse occurred in 9 cases of monotherapy(9/91 cases,9.89％) and in 19 cases of polytherapy (19/36 cases,52.78％).According to the seizure control period (period between the beginning of antiepileptic treatment and AED withdrawal),14 cases relapsed among 37 cases with the seizure control period of 2 to 3 years (37.84％),8 cases relapsed among 51 cases with the period of 3 to 4 years (15.69％),and 6 cases relapsed among 39 cases with the period of 4 to 5 years(15.38％).According to AED tapering off period,10 cases relapsed among 24 cases with the period of 3 months (41.67％),9 cases relapsed among 36 cases with the period of 3-6 mc ths (25.00％),and 9 cases relapsed among 67 cases with the period of over 6 months(13.43％).Factors associated with an increased risk of relapse were age of epilepsy onset,seizure type,route of administration,timing of antiepileptic trug withdrawal,tapering speed,which were had statistical significance (x =8.051,6.780,16.896,27.607,7.576,8.451,all P ＜0.05).Gender difference was not associated with the risk of relapse(x2 =0.187,P ＞ 0.05).Conclusions Factors associated with an increased risk of relapse are age of epilepsy onset,seizure type,route of administration,timing of antiepileptic drug withdrawal,tapering speed.Standard therapies of early treatment,adherence to medication for at least 3 years,taper period for more than 6 months are associated with a decreased probability for relapse.