The Study Of Correlation Between ¹³¹I Turnover Rate And The Effect Factors Of Graves' Disease

Objective:Evaluate whether genders, age, size of thyroid, level of thyroxin, level of thyroid stimulating hormone (TSH) influence iodine turnover rate (ITR). Identify the potential possible effective factors for effective half life (Teff) of Graves'diseases through correlation analysis. Achieve reliable effective half life of the patients by avoiding those factors, in order to establish personal therapeutic 131I dose for patients, which can not only reduce their time and spending but also have satisfied efficacy in clinical practice.Method:Choose 1604 Graves'patients who have routine inspection, such as thyroid function, the level of thyroxin, the size of thyroid and relative medical history. Use iodine turnover rate as dependent variable, and the eight chosen possible effect factors as independent variable, analysis with SPSS 13.0 software. First correlation analysis was use in univariate analysis for each possible factor, then multi-stepwise regression was use in multivariate analysis for those factors.Result1. Univariate Analysis ①Female patients'average iodine turnover rate is higher than male patients', P (sig=0.000)<0.01, there are statistical significance, which means female patients'average iodine turnover rate is generally higher than male patients'.②The size of thyroid and iodine turnover rate is positively correlated, r=0.292, p (sig=0.000)<0.01, which means the rate increase when the size of thyroid grow.③Age and iodine turnover rate is negatively correlated, r=-0.107, p (sig=0.000)<0.01, which means the rate decrease when patients get older.④T3 and iodine turnover rate is positively correlated, r=0.195, p (sig=0.000)<0.01, which means the rate increase as T3 level of peripheral blood raise.⑤T4 and iodine turnover rate is positively correlated, r=0.114, p (sig=0.000)<0.01, which means the rate increase as T4 level of peripheral blood raise.⑥There is no significant correlation between TSH level and iodine turnover rate, r=-0.002, p (sig=0.924)>0.01, which means the rate does not change with the level of TSH.⑦FT3 and iodine turnover rate is positively correlated, r=0.288, p (sig=0.000)<0.01, which means the rate increase with FT3 level of peripheral blood, and it is the most effective factor among all the thyroxin.⑧FT3 and iodine turnover rate is positively correlated, r=0.204, p (sig=0.000)<0.01, which means the rate increase with FT4 level of peripheral blood.Summary, gender is an effect factor for ITR, female'ITR is higher than men'; age is negatively correlated with ITR; the size of thyroid, the level of FT3, FT4, T3 and T4 are negatively correlated with ITR, significant correlation are found in the level of FT3 and the size of thyroid; there is not significant statistical correlation between TSH level and ITR.2. Multivariate analysisAfter multi-stepwise regression, the possible effective factors significantly decrease, only FT3 level, the size of thyroid and genders remain meaningful. Their standard regression coefficients are 0.248, 0.197 and 0.084。According to regression equation, FT3 level can significantly effect ITR and the effect of genders is the weakest for ITR.Conclusion:1. FT3 level, the size of thyroid are positively correlated with 1311 turnover rate of Graves'patients, in addition, female Graves' patients have considerable higher ICR comparing to male patients.2. There are not significant correlation between age, the level of T3, T4, TSH, FT4 and ICR. Consider all those outcomes, the effects for the size of thyroid and the level of thyroxin (especial FT3) should be taken into account when using iodine turnover rate to calculate Teff, so as to establish reasonable personal therapeutic 1311 dose for each patient base on relatively accurate Teff.