Serum Thyroid Stimulating Hormone Reference Intervals In Jiangxi Healthy Adults And Its Influencing Factors

Objective：Thyroid disease is a common clinical disease and TSH is the key tothe diagnosis of thyroid diseases. But the current serum TSH reference intervals iscontroversy as they were established from unselected background populations. Thepurpose of the subject is to redefine the TSH reference interval in the healthy adultsin Jiangxi Province and analyze the influence factors of TSH reference value range.Methods: Serum TSH concentrations were derived from1000healthy,non-pregnant Jiangxi people. Firstly, the questionnaire survey was conducted. Andthe possible effects of age, sex, thyroid peroxidase antibody and thyroid globulinstatus were evaluated. The data were analyzed by SPSS17.0. The95%confidenceintervals was used to calculated the TSH reference intervals. Skewness of TSH resultsand the Kolmogorov-Smirnov test were used to assess normality of the data. Thedifference of TSH among the groups were compared using t test, Moreover weevaluated the factors that the gender, thyroid antibodies and other medical historyeffects on TSH reference range,LSD test was used to evaluate the age and body massindex (BMI) effects on TSH reference range.Results: After excluding less than18years old, TPOAb-positive, goiter recentlytaking iodine containing foods, thyroid diseases history and subject and familyhistory, a reference population of463subjects was obtained. The K-S test showed anon-Gaussian distribution for TSH. The ln-transformed TSH results fit the curve ofGaussian distribution. In this study, the new reference range0.59-4.95mIU/L wasderived from the463healthy volunteers who were s older than18years. TSH level infemales was0.68-5.21mIU/L, THS levels in males was0.55-4.76mIU/L, the females’was higher than males’. The difference was statistically significant (P<0.05). TSHconcentrations was affected by factors such as the gender and positive thyroidantibodies (P<0.05).The age, body mass index (BMI) and other medical history werenot the factors that influenced TSH level (P>0.05).Conclusion:1.The gender and positive thyroid antibodies can affect TSHconcentrations. 2. Now the upper limit and lower limit of TSH were increased. It is different from themanufactures’ reference intervals. Different areas and laboratory should establish thelocal TSH reference range.