Study Of The Iodine Nutrition Status And The Corrected Evaluation On Urinary Iodine Excretion In Type 2 Diabetes Mellitus

ObjectivesTo study the occurrence and influencing factors of thyroid disease in type 2diabetes mellitus,and to evaluate the iodine nutrition status and the validity of urinary iodine/creatinine ratio?UI/Cr?adjustments from spot urines.To explore the effect of iodine nutrition on thyroid diseases in type 2 diabetes mellitus,and to further investigate the effect of urinary glucose on urinary iodine excretion.MethodsA total of 232 inpatients with type 2 diabetes mellitus were enrolled.Twice repeated spot urine and complete 24-hour urine were collected in a 7-9 days interval.According to the history and thyroid function results,the patients were divided into the group without thyroid diseases and the other group with thyroid diseases.According to the urine iodine data,88 patients were screened.According to glucose data,the patients were divided into two groups:1)high glucose status at admission;2)controlled status after treatment.Compare and analyze the clinical data retrospectively,to study the occurrence and influencing factors of thyroid disease in type 2 diabetes mellitus.Measure 24-hour urinary volume?24h UV?,urinary iodine and creatinine concentration?UIC and UCrC?from spot urine and 24-hour urine,to calculate the Urine Iodine to Creatinine?UI/Cr?,24-hour urine creatinine excretion?24h UCrE?and Measured 24-hour urine iodine excretion?24h UIE?.Measured 24h UIE was calculated by 24h UIC multiplying 24h UV.Urinary iodine and creatinine concentration were determined by ammonium persulfate digestion-arsenic trioxide catalytic spectrophotometry and picric acid spectrophotometry,respectively.Results1.The prevalence of thyroid diseases in type 2 diabetes mellitus was 54.7%,the prevalence of women was higher than men?28.0%vs 26.7%?.The prevalence of thyroid nodule was highest at 6.5%,subclinical hypothyroidism?SHO?was 6.5%,clinical hypothyroidism?CHO?was 3.4%,and low T₃ syndrome was 1.7%.2.The age and serum TSH levels were much higher in patients with thyroid diseases than patients without thyroid diseases.3.The iodine nutrition status in the study was suitable,but 19.5-29.9%of the population were insufficient,and 2.3%were excessive.No relationship was found between urinary iodine and the prevalence of thyroid disease in type 2 diabetes mellitus.4.No relationship was found between urinary iodine and the level of blood glucose in type 2 diabetes mellitus.5.The Urine Iodine to Creatinine was strongly correlated with Measured 24h UIE?r=0.716;r=0.789?,which was stronger than the spot urinary iodine concentration.The Urine Iodine to Creatinine may be an effective and reliable indicator to evaluate the iodine nutrition status of population or individuals in type 2 diabetes mellitus.Conclusions1.The prevalence of thyroid dysfunction in type 2 diabetes mellitus was significantly increased,and thyroid nodule is the most common one.Routine thyroid determination is recommended in diabetes mellitus.2.The iodine nutrition status of type 2 diabetes mellitus is in a suitable state,but there are still some patients in the state of insufficient or excessive.No relationship was found between urinary iodine and the prevalence of thyroid disease in type 2 diabetes mellitus.3.No relationship was found between urinary iodine and the level of blood glucose in type 2 diabetes mellitus.4.The ratio of urine Iodine to Creatinine has a good correlation and consistency with the Measured 24h UIE,may be an effective and reliable indicator to evaluate the iodine nutrition status of population or individuals in type 2 diabetes mellitus.