Causal Relationship between Subacute Thyroiditis and Papillary Thyroid Cancer: a two-sample Mendelian Randomization Analysis

Background According to clinical studies, Subacute Thyroiditis and Papillary Thyroid Cancer are two diseases with high incidence in thyroid diseases. Although there are reports of coexistence between them, the link between the two is still unknown. Therefore, we used a two-sample Mendelian randomization (MR) method to evaluate the causal effect of subacute thyroiditis on papillary thyroid carcinoma (PTC). Method The FinnGen database was used as the data source, and P < 5x10-8 was used as the threshold to screen the single nucleotide polymorphism (SNP) of subacute thyroiditis as an instrumental variable. MR-Egger, weighted median method, inverse variance weighting (IVW), simple mode and weighted mode were used to evaluate the causal association between subacute thyroiditis and papillary thyroid carcinoma using selected instrumental variables. Result According to inverse variance weighting (IVW) analysis, there is a causal relationship between subacute thyroiditis (SAT)and papillary thyroid carcinoma (PTC), in which SAT has a protective effect on PTC. The occurrence of SAT significantly reduced the incidence of PTC (OR = 0.876; 95% CI: 0.807,0.952; p = 0.002). Egger intercept test and Cochran 's Q test showed that the results of IVW analysis were reliable. Conclusion The causal link between SAT and PTC was established through MR analysis, and it was also found that SAT reduced the incidence of PTC.