Evaluation of efficacy of levothyroxine tablets in the treatment of nephrotic syndrome with hypothyroidism: A systematic review and meta-analysis

Objective To systematically assess the efficacy of levothyroxine tablets in the treatment of nephrotic syndrome with hypothyroidism. Methods A data search was done on CBM, CNKI, VIP, PubMed/Medline, Cochrane Library, Web of Science, Embase and Wan Fang databases, so as to find studies from database development up to 18^th-Jan-2019 that use the levothyroxine to treat patients who were diagnosed as nephrotic syndrome (NS) with hypothyroidism. Two researchers retrieved the data and extracted studies separately. Data analysis was done by Stata software. Results A total 16 studies were included, which contained 826 patients. The results about meta-analysis were:in the first two months of treatment with levothyroxine tablets, there was no significant difference in the improvement effect between the two groups. After more than 3 months, the left thyroxine tablets group had higher remission rate than the untreated group (1 month:RR=2.03, 95% CI 0.41~9.97, P=0.107; 2 months:RR=1.43, 95% CI 0.85~2.43, P=0.181; 3 months:RR=1.59, 95% CI 1.36~1.86, P<0.01; 6 months:RR=1.53, 95% CI 1.32~1.77, P<0.01; 12 months:RR=1.34, 95% CI 1.11~1.63, P<0.001). Comparisons between the treatment group and the control group, in increase magnitude in the level of FT3 (SMD=2.29, 95% CI 1.58~3.00, P<0.01), the level of urinary protein (WMD=-1.21 g/L, 95% CI -2.19~-0.22, P<0.01) and the edema elimination rate (WMD=-10.55 d,95% CI -12.53~-8.56,P<0.01), showed statistically significant differences. The difference in the time for negative transformation of urinary protein between the two groups were not statistically significant (SMD=-2.05, 95% CI -4.20~0.10, P=0.062). Conclusions Treatment with levothyroxine in patients with NS and hypothyroidism can reduce the burden on the kidneys, accelerate the recovery of thyroid function, and promote a good prognosis.