Cardiovascular Risk Factors in Children and Adolescents with Subclinical Hypothyroidism: A Meta-analysis and Systematic Review

Introduction: Subclinical hypothyroidism(SCH) is serum thyrotropin slightly increased, while serum free thyroxine level in the normal range, many studies are proving that SCH does increase cardiovascular risk in adults. However, current studies on cardiovascular risk in children and adolescents with SCH have not been conclusive. Therefore, we did a meta-analysis and systematic review of the included case-control and cross-sectional studies to make up for the lack of data in this direction. Methods: : We searched the following databases from its inception until May 9, 2020: PubMed, EMBASE, Web of Science, Cochrane Library, CNKI, Wanfang, and VIP. The Newcastle-Ottawa Scale was be used to check on the quality of these studies. I 2 statistics and subgroups were be used to analyze heterogeneity. The sensitivity analysis assessed the stability of the results against the overall effect by “leave-one-out”. When the systematic review contains more than 10 articles, funnel plots and egger regression test was be made to evaluate publication bias. Result: Twelve observational studies were enrolled in our meta-analysis. TC was significantly higher in SCH patients than in normal thyroid subjects (WMD=6.01, 95% CI: 3.70-8.31, P<0.00001), TG (WMD=9.86, 95% CI: 5.72-14.01, P<0.00001), LDL (WMD=4.33, 95% CI: 1.78-6.87, P=0.0009), and IVRT (WMD=7.85, 95% CI: 3.99-11.72, P<0.0001). At the same time, we found no significant differences in HDL, IMT, and HOMA-IR between the two groups. Conclusions: : Our study confirmed that SCH changes lipid profile and heart function in children and adolescents. Register: The protocol of this systematic review and meta-analysis was registered on the NPLASY (No. 202040182). The protocol has been published, it can be found in https://pubmed.ncbi.nlm.nih.gov/32756074/.