Curative Effect of Low Dose of Levothyroxine in Treatment of Congenital Hypothyroidism

Objective To investigate the clinical efficacy of different doses levothyroxine in treatment of congenital hypothyroidism( CH) to find the optimal therapeutic dosage. Methods A total of 60 patients with CH were randomly divided into low-dose group( n = 30) and routine dose group( n = 30),and all patients received levothyroxine treatment. The routine dose group was treated with 10-15 μg /( kg·d) of initial dose and 80-100 μg / d of maintenance dose; the low-dose group was treated with 8-10 μg /( kg·d) of starting dose and 50-80 μg / d of maintenance dose. The thyreoid functional parameters in two groups were observed after treatment for 2 months,and intelligence status was also observed in patients who received continued treatment at the age of two. Results After treatment for 2 months,the differences of values of FT3and FT4in two groups were not statistically significant( P 0. 05); TSH value of( 2. 6 ± 1. 2) mU / L in low-dose group was significantly lower than that of( 11. 3 ± 8. 2) mU / L in routine dose group,and the differences were statistically significant( P 0. 01).The changes of performance intelligence quotient( PIQ),verbal intelligence( VIQ) and full-scale intelligence quotient( FIQ)were detected by Wechsler intelligence scale( C-WYCSI) when patients were two years old. The indexes in low dose group were significantly higher than those in routine dosage group,and the differences were statistically significant( P 0. 01).Conclusion Low dose of levothyroxine in treatment of congenital hypothyroidism may improve thyroid function and intelligence level,and the recommended doses are 8-10 μg / d of initial dose and 50-80 μg / d of maintenance dose.