The Influence of Low Serum Sodium Levels on the Risk of Repeated Febrile Convulsions during the Same Febrile Illness

ABSTRACT

PURPOSE: Hyponatremia may be common in febrile convulsions and lower the threshold for febrile convulsions. We evaluated the association between hyponatremia and febrile convulsions and also examined the effect of hyponatremia on the recurrence of convulsions during the same febrile illness. METHODS: Serum sodium levels were measured from 98 children with febrile convulsions, among whom there were 21 recurrent and 77 non-recurrent patients during the same febrile illness. Also, as a control group, we selected 32 febrile and 48 non-febrile children, who did not have febrile convulsions. Results were analyzed by Student's t-test and logistic regression. RESULTS: The average serum sodium level in febrile convulsions was 135.5+/-3.7 mEq/ L, which was significantly lower than 138.7+/-3.2 mEq/L of febrile children and 138.0+/-3.0 mEq/L of non-febrile children in the control group(P<0.05). The average serum sodium level in recurrent febrile convulsions during the same febrile illness was 133.1+/-4.1 mEq/ L, which was significantly lower than 136.1+/-3.3 mEq/L in non-recurrent febrile convulsions(P<0.05). CONCLUSION: The serum sodium levels of the patients with febrile convulsions were significantly lower than those of the children in the control group. Also, the lower the sodium levels were, the higher recurrent febrile convulsions during the same febrile illness occurred.