Association between the Systemic Immune-Inflammation Index and Thyroid Function in U.S. Adults

Figure 2

Weighted RCS analysis of the association between lnSII and thyroid function. (a) RCS curve of the association between FT3 and lnSII; (b) RCS curve of the association between TT4 and lnSII; (c) RCS curve of the association between FT3/FT4 and lnSII; and (d) RCS curve of the association between TG and lnSII. The model was adjusted for age, sex, race, marital status, family poverty income ratio, education level, body mass index, smoking status, alcohol use, diabetes, glycated hemoglobin, alanine aminotransferase, aspartate aminotransferase, creatinine, urine iodine concentration, and total cholesterol.

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