Effect of carbamazepine therapy on homocysteine, vitamin B12 and folic acid levels in children with epilepsy.

OBJECTIVE To compare the levels of homocysteine, vitamin B12 and folic acid before and after 6 months of carbamazepine therapy and to correlate them with carbamazepine level at 6 months. DESIGN Prospective comparative study. SETTING Tertiary care centre in North India. PARTICIPANTS 51 children (2-12 years of age) presenting with motor partial seizures. INTERVENTION Carbamazepine (10-20 mg/kg/day) for 6 months. MAIN OUTCOME MEASURE Change in serum homocysteine, B12, folic acid level. METHODS Fasting venous samples were collected before carbamazepine therapy and after six months. Homocysteine was analyzed using homocysteine enzyme immunoassay. Vitamin B12 and folic acid were estimated using electrochemiluminesence technique. Carbamazepine levels were measured at 6 months. RESULTS Of the 51 children, 36 (males-21), were followed up and their data analyzed. Mean homocysteine level was 11.51±3.95 umol/L at recruitment and 11.77±6.65 umol/L at six months (P=0.785). At recruitment 6(16%) children had homocysteine level above 15 umol/L which increased to 10(27%) at 6 months. Mean vitamin B12 at recruitment was 292.1±111.2 pg/mL and 297.8±82.9 pg/mL at 6 months (P=0.764). Mean folic acid at recruitment was 9.98±3.45 ng/mL and 10.66±3.97 ng/mL at 6 months (P=0.358). There was no correlation between carbamazepine levels with homocysteine, vitamin B12 and folic acid (P>0.05). There was no effect of age, sex or dietary pattern on homocysteine levels. CONCLUSIONS Hence 6 months of carbamazepine therapy did not cause significant change in serum levels of homocysteine, vitamin B12 and folic acid.