Is there any association between vitamin D deficiency and anti-thyroid peroxidase positive hypothyroidism: A cross-sectional study

Background: Vitamin D deficiency is prevalent worldwide and it is believed to have a role as an immune modulator. However, the association between vitamin D levels and anti-thyroid peroxidase positive (TPOAb) hypothyroidism is still controversial. Aim: To elucidate the association between vitamin D levels and anti-thyroid peroxidase (TPOAb) positive hypothyroidism. Materials and Methods: Serum Vitamin D, thyroid peroxidase antibody, and thyroid function test were measured in 105 patients, who were sub-grouped into the TPOAb positive and TPOAb negative hypothyroidism category. Results: Vitamin D level, was found significantly lower in patients with TPOAb positive hypothyroidism as compared to patients TPOAb negative hypothyroidism (13.275.18vs. 17.746.03ng/ml, respectively, P<0.05), as well as between patients with TPOAb positive hypothyroidism and control group (13.275.18vs. 29.669.41 ng/ml, respectively, P<0.05). Within the patients' group, there was a significant negative correlation between serum 25 (OH) vitamin D and TSH (r=−0.438, P<0.05), anti-TPO (r=−0.275, P<0.05). Furthermore, insignificant positive correlations were recorded between serum 25 (OH) vitamin D, and each of T3, T4 (r=–0.056, 0.097, P>0.05). Conclusion: The current study observed significant low levels of 25(OH)D3 in TPOAb positive hypothyroid patients.

Anti-thyroid peroxidase antibody and thyroid cysts among the general Japanese population: a cross-sectional study

BACKGROUND@#Anti-thyroid peroxidase antibody (TPO-Ab) has been shown to cause autoimmune thyroiditis by inducing a deleterious influence on thyroid hormone synthesis. Further, thyroglobulin, which has an important role in thyroid hormone synthesis, is reported to be high in the fluid from thyroid cysts. Therefore, TPO-Ab could be associated with the presence of thyroid cyst, partly by affecting the activity of thyroid hormone synthesis.@*METHODS@#To investigate the association between TPO-Ab and thyroid cysts, we conducted a cross-sectional study of 1432 Japanese with normal thyroid function [i.e., normal range of free triiodothyronine (free T3) and free thyroxine (free T4)] between the ages of 40 and 74 years, who participated in an annual health check-up.@*RESULTS@#In men, the statistical power did not reach a statistical significance value. Additionally, subjects with TPO-Ab showed lower odds ratios (ORs) of thyroid cysts than those without TPO-Ab. In women, subjects with TPO-Ab showed significantly lower ORs of thyroid cysts than those without TPO-Ab. The fully adjusted ORs were 0.68 (0.40, 1.18) for men and 0.40 (0.27, 0.60) for women. When evaluating the association between logarithmic values of TPO-Ab titer and thyroid cysts in both men and women, a notable inverse correlation was observed. The fully adjusted ORs were 0.68 (0.50, 0.92) for men and 0.68 (0.57, 0.81) for women.@*CONCLUSION@#TPO-Ab titer revealed to be inversely associated with thyroid cysts among Japanese with normal thyroid function. The presence of a thyroid cyst could indicate a lower risk of having TPO-Ab among the general population with normal thyroid function.

The relevance between the level of thyroid hormone and TPOAb during gestation period / 重庆医学

Objective To study the relevance between the level of thyroid hormone and anti‐thyroid peroxidase antibody (TPOAb) during gestation period .Methods From November 2011 to May 2014 ,150 gravidas were chosen as objectives ,and were divided into 2 groups according TPOAb .The clinical feature ,level of thyroid hormone ,pregnancy outcome ,and complication of neo‐phyte between 2 groups were compared .Results In 150 gravidas ,44 were positive in TPOAb and 106 were negative .The age ,ges‐tational weeks and BMI between two groups had no statistical difference(P>0 .05) .At the early and middle pregnancy as well as at the late pregnancy ,the level of thyroid hormone between two groups had statistical difference(P<0 .05);In study group ,the level of thyroid hormone of early and middle pregnancy and that of late pregnancy had statistical difference(P<0 .05) .The rate of unde‐sirable gestational outcome and that of neophyte complication between two groups had statistical difference(P<0 .05) .Conclusion During gestation period ,the TPOAb was significant for the diagnosis of the sub‐clinical hypothyroidism ,as well for prognosis of gravidas .

Subclinical Hypothyroidism among Patients with Depressive Disorders

Subclinical hypothyroidism (SHT) is a biochemical diagnosis, defined as an elevated Thyroid Stimulating Hormone (TSH) with normal free thyroxine (FT4). It affects 4-10% of the adult population and is more prevalent in elderly women. Its commonest cause is autoimmune thyroiditis, detected by antithyroid peroxidase antibody (TPO-Ab). About 2-5% of SHT patients progress to overt hypothyroidism annually. The SHT prevalence among depressed patients ranges between 3% and 17%. This study aimed to determine the prevalence of SHT and TPO-Ab positivity among patients diagnosed with depressive disorders. It was a cross-sectional study carried out in the Universiti Kebangsaan Malaysia Medical Centre over a 12 months period. Serum TSH, FT4 and TPO-Ab were measured. Results showed that 82% of depressed patients were euthyroid, 4% had SHT, 11% had subclinical hyperthyroidism and 2% had discordant thyroid function. TPO-Ab positivity among the subjects was 7%, one of whom had SHT. In conclusion, the prevalence of SHT and TPO-Ab positivity in the study population, at 4% and 7%, respectively, were comparable to previous findings.

Low Serum Vitamin D Is Associated with Anti-Thyroid Peroxidase Antibody in Autoimmune Thyroiditis

PURPOSE: The association between autoimmune thyroid diseases (AITDs) and vitamin D deficiency is controversial. We aimed to evaluate the relationship between serum 25-hydroxy-vitamin D3 [25(OH)D3] and anti-thyroid antibody levels. MATERIALS AND METHODS: 25(OH)D3, anti-thyroid antibodies, and thyroid function measured in 304 patients who visited the endocrinology clinic were analyzed. The patients were subgrouped into the AITDs or non-AITDs category according to the presence or absence of anti-thyroid antibodies. The relationship between anti-thyroid peroxidase antibody (TPOAb) and 25(OH)D3 was evaluated. RESULTS: The patients with elevated anti-thyroid antibodies had lower levels of serum 25(OH)D3 than those who did not (12.6+/-5.5 ng/mL vs. 14.5+/-7.3 ng/mL, respectively, p<0.001). Importantly, after adjusting for age, sex, and body mass index, a negative correlation (r=-0.252, p<0.001) was recognized between 25(OH)D3 and TPOAb levels in the AITDs group, but this correlation did not exist in the non-AITDs group (r=0.117, p=0.127). 25(OH)D3 level was confirmed as an independent factor after adjusting for co-factors that may affect the presence of TPOAb in the AITDs group. CONCLUSION: 25(OH)D3 level is an independent factor affecting the presence of TPOAb in AITDs. The causal effect of 25(OH)D3 deficiency to AITDs is to be elucidated.

Comparison of Particle Agglutination Assay and ELISA for Anti-thyroid Autoantibodies

BACKGROUND: Measurements of serum anti-thyroglobulin antibody (anti-Tg) and anti-thyroid peroxidase antibody (anti-TPO) are important for the diagnosis of autoimmune thyroid diseases. Although ELISA is most commonly used for the detection of anti-thyroid autoantibodies, other methods like particle agglutination assay (PA) or radioimmunoassay (RIA) are still being used in clinical laboratories. There are few studies about the comparison between PA and ELISA, and we evaluated the validity of these assays in this study. METHODS: We have used three methods, PA (Fujirebio Inc.), ELISA-1 (Zeus Scientific Inc.), and ELISA-2 (Orgentec Diagnostika) for the measurements of titers or concentrations of anti-thyroid autoantibodies. A total of 212 patients belonging to six different disease groups were tested: 40 patients for anti-Tg only, 64 for anti-TPO (or anti-microsome) only, and 108 for both antibodies. All test results were compared with each other in six disease groups. RESULTS: Concordance of positive or negative results was obtained in 78.5-97.3% of the samples tested, and positive rates of three methods were similar in autoimmume thyroid disease group. In the comparable concentration range, the correlation coefficients were 0.328-0.820 between the two ELISAs or between ELISA and PA. CONCLUSIONS: Positive or negative decisions by three assay systems have high concordance rates, and antibody levels measured by three methods correlate well in the comparable concentration range. The ELISA-1 shows less non-specific reactions, better discrimination in low level of autoantibodies, and the highest positive rate in autoimmume thyroid disease group.