Thyroid volume and its relation to anthropometric measures in a healthy cuban population

The determination of the optimal threshold on measurement of thyroid volume using quantitative SPECT/CT for Graves' hyperthyroidism

PURPOSE

To investigate the optimal threshold for measuring thyroid volume in patients with Grave's hyperthyroidism (GH) by SPECT/CT.

MATERIALS AND METHODS

A 53 mL butterfly-shaped hollow container made of two 45-degree transparent elbows was put into a NEMA IEC phantom tank. The butterfly-shaped container and the tank were then filled with Na99mTcO4 of different radioactive concentrations, respectively, which could simulate thyroid gland with GH by different target-to-background ratios (T/B) (200:1, 600:1, 1000:1). The different T/B of planar imaging and SPECT/CT were acquired by a Discovery NM/CT 670 Pro SPECT/CT. With Thyroid software (Version 4.0) of GE-Xeleris workstation, the region of the thyroid gland in planar imaging was delineated. The thyroid area and average long diameter of both lobes were substituted into the Allen formula to calculate the thyroid volume. The calculation error was compared with the actual volume. Q-Metrix software was used to perform CT-based attenuation correction, scatter correction, resolution recovery. Ordered-subsets expectation maximization was used to reconstruct SPECT data. 20%, 25%, 30%, 40%, 50%, 60% thresholds were selected to automatically delineate the volume of interest and compared with the real volume, which determinated the optimal threshold. We measured the thyroid volume of 40 GH patients using the threshold and compared the volumes obtained by planar imaging and ultrasound three-dimensional. The differences of the volumes with different T/B and thresholds were compared by the ANOVA and least significant difference t test. The volumes delineated by SPECT/CT were evaluated using ANOVA, least significant difference t test, correlation analysis and, linear regression and Bland-Altman concordance test plot. The differences and consistency of thyroid volume were compared among the above three methods.

RESULTS

There was no significant difference in the results between different T/B models (P > 0.05). The thyroid volume calculated by the planar imaging formula method was higher than the real volume, with an average overestimation of 22.81%. The volumes delineated by SPECT/CT threshold automatically decreased while the threshold increased. There were significant differences between groups with different thresholds (P < 0.001). With an average error of 3.73%, the thyroid volume analyzed by the threshold of 25% was close to the results of ultrasound measurement (P > 0.05). Thyroid volume measured by planar imaging method was significantly higher than ultrasound and SPECT/CT threshold automatic delineation method (P < 0.05). The agreement between the SPECT/CT 25% threshold and ultrasound (r = 0.956, b = 0.961) was better than that between the planar imaging and ultrasound (r = 0.590, b = 0.574). The Bland-Altman plot also showed that the thyroid volume measured by the 25% threshold automatic delineation method was in good agreement with the ultrasound measurement.

CONCLUSIONS

The T/B has no effect on the measurement of thyroid volume in GH patients; planar imaging method can significantly overestimate thyroid volume in GH patients, and 25% threshold automatic delineation method can obtain more accurate thyroid volume in GH patients.

[Normal values for adult thyroid volume on ultrasound - where do they come from and how should they be evaluated?]

The upper limit for the thyroid volume is 18 ml for women and 25 ml for men. These reference values are used and taught in many clinics and practices across several disciplines. The thyroid volume is a relevant factor for the treatment course. But where do the standard values for thyroid volumes come from, what kind of studies have been carried out to establish them? Should these upper limits be used as an universal standard in clinical routine, and which factors can influence the physiological organ size? The following article is dedicated to a critical review of the commonly used reference values for the thyroid volume of adults.

Influencing Factors and New Reference Intervals of Adult Thyroid Volume in Iodine-Sufficient Areas of China

The diagnosis of goiter is based on the thyroid volume measured by ultrasound in which iodine plays an important role. The purpose of this study was to evaluate the factors that affect thyroid volume and update the reference range of thyroid volume to provide a new basis for the diagnosis and treatment of goiter. A study population from mainland China was evaluated in the Thyroid disorders, Iodine status and Diabetes Epidemiological (TIDE) study. Thyroid size was measured by ultrasound, and thyroid volume was calculated. A quantile regression model was used to analyze the influence of related factors on the thyroid volume at each percentile. The median urinary iodine concentration (UIC) was 185.54 μg/l. The quantile regression model suggested that body surface area (BSA) and thyroid-stimulating hormone (TSH) were positive and negative factors for thyroid volume, respectively (p < 0.01). Excess iodine reduces the median and lower limits of thyroid volume. In iodine-sufficient areas, smoking is no longer a risk factor. The reference value range of thyroid volume stratified by sex was 3.92-19.06 ml for males and 3.1-16.17 ml for females. The maximum reference ranges for stratification by sex and BSA were 4.25-20.98 ml for men and 3.44-18.31 ml for women. The iodine nutrition level of the population in mainland China is sufficient. Iodine has the potential to alter the effect of certain factors on thyroid volume and effect is not regional. The new reference interval of adult thyroid volume based on sex and BSA has been updated, which can be used as a reliable reference for updating the diagnostic criteria of endemic goiter.

References values and predictive factors for thyroid volume in pregnant women

Objective

Thyroid volume varies within each population according to different clinical and biochemical factors and can change during pregnancy. The present investigation was aimed to determine the reference values for thyroid volume in pregnant women and their predictive factors.

Materials and methods

A cross-sectional study was carried out with 360 healthy pregnant women. The following variables were examined: maternal age, gestational age, skin color, current smoking status, parity, use of iodinated supplements, body mass index, thyrotropin, total and free thyroid hormones, thyroglobulin, antithyroid antibodies, chorionic gonadotropin, cholesterol and triglycerides.

Results

The mean thyroid volume was 5.3 ± 1.3 mL, 5.4 ± 1.6 mL and 5.6 ± 2.5 mL in the first trimester, second trimester and third trimester, respectively. The reference interval was 2.47-9.49 mL in the first trimester, 3.17-9.01 mL in the second trimester, and 3.00-12.38 mL in the third trimester. Free triiodothyronine and triglycerides were predictors of thyroid volume (corrected R2 = 0.12; p = 0.000).

Conclusion

This study is the first to determine the reference values for thyroid volume and its predictive factors in pregnant women from Cuba, a Caribbean island with sustainable elimination of iodine deficiency disorders.

Association of polycyclic aromatic hydrocarbon internal exposure and urinary iodine concentration with thyroid volume in children

Thyroid volume was proposed as a factor for malignancy in evaluating thyroid nodules. Previous studies have demonstrated the endocrine disrupting effect of polycyclic aromatic hydrocarbons (PAHs), but studies on the association between internal exposure of PAHs and thyroid volume are still scarce. In this work, we evaluated the association of polycyclic aromatic hydrocarbon internal exposure and urinary iodine concentration with thyroid volume in 590 school-age children without thyroid disease in Guangzhou, China. Urinary hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs), urinary iodine concentrations, and thyroid volumes were measured. The mean concentrations of urinary iodine and ΣOH-PAHs were 271.1 μg/L and 3.27 μg/L, respectively, and the mean thyroid volume was 2.4 mL. The associations of urinary iodine and OH-PAH concentrations with thyroid volume were investigated by multivariable linear regression and the Bayesian kernel machine regression models. Urinary ΣOH-PAHs were observed to be significantly positively associated with thyroid volume in multivariable linear regression models. The increase in each unit in the log-transformed concentration of ΣOH-PAHs caused 3.88% change in thyroid volume. The Bayesian kernel machine regression model demonstrated a positive joint effect of increased urinary ΣOH-PAHs on thyroid volume. Moreover, urinary ΣOH-PAHs were statistically significant linked to urinary iodine, and iodine mediated the relationship between urinary OH-PAHs and thyroid volume with the mediated proportions of 15.2.

Normal thyroid volume in subjects evaluated in a primary ambulatory setting in Liguria

BACKGROUND

Ultrasonography (US) is the simplest method of evaluating thyroid volume (TV). The current normal TV in Liguria is not known. The aim of this study was to obtain normative data on TV in Liguria, Italy.

METHODS

From 3552 files of endocrine evaluations registered in a primary outpatient setting, we selected 483 files on euthyroid subjects (383 females and 100 males) with a normal echoic pattern on US. The inclusion criterion was the absence of thyroperoxidase autoantibodies and drugs known to interfere with thyroid hormone secretion or metabolism. TV was calculated by means of US. Anthropometric characteristics, smoking habits and the district where subjects lived were registered.

RESULTS

Less than 50% of patients were not taking any drug. The percentage of obesity was similar in both sexes. TSH levels were similar in males and females. Median TV was 8.0 mL (IQR: 6.7-9.8 mL) in females and 11.8 mL (9.3-15.6 mL) in males (P<0.0001). In females, TV was greater (P=0.01) in smokers than in non-smokers. In both sexes, the right lobe was significantly (P<0.0001) larger in volume than the left. Post-hoc analysis did not show any differences among age-groups in either females or males. In females, but not in males, TV differed significantly (P=0.0002) according to the district of residence. A significant positive correlation was found in both groups between TV and weight, height, BMI and BSA.

CONCLUSIONS

Reference values of TV in the Ligurian population are now available. TV in the general population could be compared with these normative data.

Sustained Elimination of Iodine Deficiency Within the Third Decade After Compulsory Iodine Supplementation Policy in the South of Iran: A Population-Based Cross-Sectional Study

Objectives

Recently, some studies in Iran have shown mild to moderate iodine concentrations in adult and pregnant women populations despite iodine sufficiency in children. This study aimed to evaluate the urine iodine status and salt intake among adult households in the city of Sadra, Fars province in southern Iran, and to assess its possible influencing factors.

Method

Participant households for this cross-sectional study were selected using randomized cluster sampling in the city of Sadra, Fars province, southern Iran from 1 February, 2021 to 30 November, 2021. Two subjects >18 y of age from each household were invited. Ninety-two subjects (24 men, 68 women) were enrolled. The participants were asked to collect their 24 h urine. They were then examined for thyroid disorders and subjected to thyroid ultrasonography and thyroid function tests. Urine samples were tested for iodine, sodium, and creatinine concentrations. Household salt intake was also estimated.

Results

Median urine iodine content (UIC) in the participants was 175 (IQR: 117, 250) μg/L, whereas the median salt consumption per person per day was 9.6 (IQR, 7.3-14.5) g. Sex, methods of salt storage, presence of goiter or thyroid nodules, the addition of salt in the cooking stage, and subclinical hypothyroidism had no effect on UIC, whereas individuals with hypertension and lower education had significantly lower iodine concentrations. UIC had a significant positive correlation with urine sodium and thyroid stimulating hormones (TSH) concentrations (P < 0.001, 0.046) and a negative correlation with thyroid volume and T4 (P = 0.029, 0.018).

Conclusion

Iodine status in the adult population of Sadra city was categorized as sufficient, although the iodine concentrations reported in Tehran were insufficient. The contributing factor can be higher salt consumption or possible higher environmental iodine concentrations in Sadra city than Tehran.

Risk factors for difficult thyroidectomy and postoperative morbidity do not match: retrospective study from an endocrine surgery academic referral centre

Hyperthyroidism, goiter and thyroiditis have been associated with complex thyroidectomy. Difficult thyroidectomies may implicate longer operating times and higher complication rates, while literature on quantification and prediction of difficulty in thyroidectomy is scant. We aim at assessing the impact of preoperative and intraoperative factors on the technical difficulty of total thyroidectomy (TT) and on the incidence of postoperative complications. We conducted a retrospective study on 197 TT from 343 thyroidectomies performed with intraoperative neuromonitoring between October 2019 and June 2022 (excluding lobectomies, nodal dissection, extra-thyroidal procedures). Operating time (surrogate of TT difficulty), postoperative hypocalcaemia, recurrent laryngeal nerve palsy and postoperative bleeding were assessed in relation to pre- and intraoperative characteristics. Vocal fold palsy(VFP) was defined as recovering < 12 months postoperatively. There were 87 thyroid cancers and 110 multinodular goiters (21 hyperfunctioning, 51 mediastinal). Median operating time was 136 min (range 51-310). Within 17.4 months overall median follow-up we recorded two transient VFPs and 12% symptomatic transient hypocalcaemia. At univariable analysis male sex (p = 0.005), BMI (p < 0.001), thyroiditis (p < 0.05), hypervascular goiter (p = 0.003) and thyroid adhesions to surrounding anatomical structures (p < 0.001) were associated with longer operating time. At multivariable analysis male male sex (p = 0.01), obesity (p = 0.001) and thyroid adhesions (p = 0.008) were factors for prolonged operating time. Above-normal anti-thyroid peroxidase antibodies correlated to transient symptomatic hypocalcemia (p < 0.001). Risk factors for complex TT were identified and did not correlate with morbidity rates. Results from this study may help optimizing operating room schedule and inform case selection criteria for training programs in thyroid surgery. Further research is required to confirm these findings.

Prevalence of thyroid dysfunction in postpartum women with suboptimal iodine and selenium and adequate iron status

OBJECTIVE

Postpartum women experience thyroid dysfunction at twice the prevalence of the general population. Adequate biosynthesis of thyroid hormones depends on three trace elements: iodine, selenium and iron. This study aimed to investigate thyroid dysfunction within a cohort of women at six months postpartum in relation to iodine, selenium and iron status.

DESIGN

This cross-sectional study was part of an observational longitudinal cohort Mother and Infant Nutrition Investigation; data obtained at six months postpartum are reported.

SUBJECTS

Mother-infant pairs (n = 87) were recruited at three months postpartum and followed up at six months postpartum (n = 78).

MEASUREMENTS

Thyroid hormones (free triiodothyronine, free thyroxine, thyroid-stimulating hormone) and thyroid peroxidase antibodies were measured. Urinary iodine concentration, breast milk iodine concentration, serum thyroglobulin, plasma selenium, serum ferritin and serum soluble transferrin receptors were determined. Nonparametric data were expressed as median (25th, 75th percentile).

RESULTS

Thyroid dysfunction was found in 18% of women, and 4% of women had iron deficiency. Median urinary iodine concentration was 85 (43, 134) µg/L, median breast milk iodine concentration was 59 (39, 109) µg/L, and median serum thyroglobulin at 11.4 (8.6, 18.6) µg/L, indicating iodine deficiency. Median plasma selenium concentration was 105.8 (95.6, 115.3) µg/L. Women with marginally lower plasma selenium concentration were 1.12% times more likely to have abnormal TSH concentrations (p = .001).

CONCLUSIONS

There was a high prevalence of thyroid dysfunction. Plasma selenium concentration was the only significant predictor of the likelihood that women had thyroid dysfunction within this cohort, who were iodine deficient and mostly had adequate iron status. Strategies are required to improve both iodine and selenium status to better support maternal thyroid function.

Nutritional iodine status and obesity

Iodine is an essential component of the thyroid hormones, thyroxine and triiodothyronine. Its availability strictly depends on iodine content of foods, which may vary from very low to very high. Inadequate iodine intake (deficiency or excess) may affect thyroid function resulting in hypothyroidism or hyperthyroidism. Based on median urinary iodine concentrations, epidemiological criteria have been established for the categorization and monitoring of nutritional iodine status of a population (or subgroups of populations). Additional methods for iodine intake assessment include measurement of thyroid size (by thyroid palpation or ultrasonography) and of biochemical parameters, such as neonatal thyroid stimulating hormone, thyroglobulin and thyroid hormones.

Recent studies carried out in overweight/obese children and adults provide evidence that body mass index (BMI) may significantly influence the above indicators, thus theoretically affecting the epidemiological evaluation of nutritional iodine status in populations.

In this short review, we analyze current knowledge on the effects of overweight and obesity on indicators of adequacy and monitoring of iodine status, namely urinary iodine excretion and thyroid volume and echogenicity.

Data on urinary iodine excretion in overweight/obese children are divergent, as both increased and reduced levels have been reported in overweight/obese children compared to normal-weight controls.

Whether gastrointestinal surgery may affect iodine absorption and lead to iodine deficiency in patients undergoing bariatric surgery has been evaluated in a limited number of studies, which excluded iodine deficiency, thus suggesting that supplements usually recommended after bariatric surgery do not need to include iodine.

Albeit limited, evidence on thyroid volume and obesity is consistent with a direct relationship between thyroid volume and BMI, irrespective of nutritional iodine status. Finally, a higher frequency of thyroid hypoechoic pattern has been described in overweight/obese children. This finding has been recently related to an increased adipocyte infiltration and thyroid parenchyma imbibition mediated by inflammatory cytokines and should be considered when the frequency of thyroid hypoechoic pattern is used as non-invasive marker to indirectly assess thyroid autoimmunity in monitoring Universal Salt Iodization programs. Further studies, specifically addressing the role of schoolchildren body mass index as a factor potentially influencing iodine intake indicators are needed.

Sex-Specific Differences in Outcomes Following Thyroidectomy: A Population-Based Cohort Study

INTRODUCTION

Numbers of thyroidectomies and awareness of postoperative quality measures have both increased. Potential sex-specific variations in clinical outcomes of patients undergoing thyroidectomy are controversial.

OBJECTIVE

The aim of this study was to investigate sex-specific differences in outcomes following thyroidectomy.

METHODS

This is a population-based cohort study of all adult patients undergoing either hemi- or total thyroidectomy in Switzerland from 2011 to 2015. The primary outcome was all-cause 30-day readmission rate. The main secondary outcomes were intensive care unit (ICU) admission, surgical re-intervention, in-hospital mortality, length of hospital stay (LOS), postoperative calcium disorder, vocal cord paresis, and hematoma.

RESULTS

Of 16,776 patients undergoing thyroidectomy, the majority of patients undergoing thyroidectomy were female (79%), with a median age of 52 (IQR 42-64) years. Within 30 days after the surgery, male patients had significantly higher rates of hospital readmission (adjusted risk ratio [RR] 1.38; 95% confidence interval [95% CI] 1.11-1.72, p = 0.008) and higher risks for postoperative ICU admission (RR 1.25; 95% CI, 1.09-1.44, p = 0.003) than female patients. There were no significant differences among sexes in the LOS, rates of surgical re-interventions, or in-hospital mortality. While postoperative calcium disorders due to hypoparathyroidism were less prevalent among male patients (RR 0.63; 95% CI, 0.54-0.72, p < 0.001), a 2-fold higher incidence rate of postoperative hematoma was observed (RR 1.93, 95% CI, 1.51-2.46, p < 0.001).

CONCLUSIONS

Male patients undergoing thyroidectomy have higher 30-day hospital readmission and ICU admission rates. Following surgery, male patients revealed higher rates of neck hematoma, while hypocalcemia was more frequent among female patients.

A community-based ultrasound determination of normal thyroid volumes in the adult population, Assin North District, Ghana

Introduction

the purpose of this study was to measure thyroid volumes among normal sub-population of Ghanaians using ultrasonography in order to help provide preliminary local thyroid gland volume reference data for use in Ghana.

Methods

this was a cross-sectional study in which the thyroid glands of 320 normal adults aged 18 to 95 years from six (6) communities in the Assin North District of Ghana were examined using ultrasonography. The volumes of the left and right lobes were summed to constitute the total thyroid volume. Information on socio-demographic characteristics and anthropometric parameters of subjects were also collected. The data were summarized using mean, standard deviation and proportions, whilst inferential analysis was done using the T-test, ANOVA test and Pearson correlation.

Results

of the 320 adults examined, 284 (88.8%) were found to have normal thyroid glands. This consisted of 164 females and 120 males whose mean ages were 42.3 (±15.9) years and 45.4 (±15.9) years respectively. The overall mean total thyroid volume (MTTV) was 6.8±2.5 mL. This was greater in the males (7.1±2.7 mL) than in the females (6.6±2.2 mL). The MTTVs for three age groups; 30-39 years (7.1±2.1), 40-49 years (7.3±2.8 mL) and 50-59 years (7.1±3.0 mL) were greater than the overall MTTV. Thyroid volume had a positive correlation with body surface area (BSA) (r=0.119, p=0.046), but not with body mass index (BMI) (r=-0.021, p=0.719).

Conclusion

this study estimated local reference values much lower than the WHO/ICCIDD thyroid volume reference values. This calls for the need for nationally representative studies to inform the establishment of standard local reference values for Ghana.

Obesity and risk of differentiated thyroid cancer: A large-scale case-control study

OBJECTIVE

Recently, the incidence of thyroid cancer as well as obesity has dramatically increased worldwide. Whether obesity contributes to the development of differentiated thyroid cancer (DTC) remains controversial. We evaluated the relationship between anthropometric measurements and DTC risk.

DESIGN/PATIENTS/MEASUREMENTS

A large frequency-matched case-control study based on hospital data was performed. A total of 10 668 DTC patients and 11 858 controls were enrolled. Body mass index (BMI), body surface area (BSA) and body fat percentage (BF%) were calculated. An unconditional logistic regression model was applied.

RESULTS

The univariate analysis showed a significant increase in DTC risk with increased height, weight, BMI, BSA and BF%. The multivariate analysis also showed a positive relationship. Based on the Chinese BMI (CN-BMI) classification, for women of all ages, the ORs for DTC risk in overweight and obesity were 1.151 (1.037-1277) and 1.292 (1.092-1.528), respectively. For men under 50, the ORs were 1.221 (1.014-1.469) and 1.520 (1.202-1.923), respectively, but the ORs for men over 50 were not significant. Additionally, BSA showed a significant association with DTC risk for both sexes under 50 (P = .02 and P < .001). BF% remained significant only for women under 50 (P = .003). However, for both sexes over 50, neither BSA nor BF% was significantly associated with DTC risk. Based on The World Health Organization BMI (WHO-BMI) classification, for all women and men over 50, the results were consistent with CN-BMI. For men under 50, BF%, but not BMI, showed a significant association with DTC risk.

CONCLUSION

BMI, BSA and BF% were positively correlated with the risk of DTC, which was potentially affected by age and sex.

Investigation of blood groups in benign thyroid diseases in Turkey

İt is known that there is a relationship between some diseases and blood groups. The objective of our study is to investigate how often ABO and Rh blood groups are seen in benign thyroid diseases, especially in autoimmune-mediated thyroid diseases, and hence whether there is an association between blood groups and thyroid diseases. A total of 958 patients who were followed due to any benign thyroid disease were included in the study. The study population comprised 958 patients, 550 with Hashimoto's hypothyroidism, 160 with non-Hashimoto's hypothyroidism, 103 with iatrogenic hypothyroidism, 93 with central hypothyroidism, and 28 with Graves' and 24 with non-Graves' hyperthyroidism. Of the patients, 47.1% belonged to the O blood group, 30% to the A blood group, 15.2% to the B blood group, and 7.7% to the AB blood group while 90% were Rh-positive. The ratio of those with the O blood group was determined to be significantly higher in the Hashimoto's hypothyroidism group compared to the other disease groups. In the non-Hashimoto's hypothyroidism group, however, the ratio of the AB blood group was statistically significantly higher. While autoimmune diseases were more common in those with the O blood group, they were significantly lower in the AB blood group (p < 0.001). In our study, we determined that the ratio of the O blood group was significantly higher among patients with hypothyroidism due to Hashimoto's thyroiditis. These findings imply that there might be a relation between O blood group and Hashimoto's thyroiditis.

Anthropometric Parameters and Thyroid Morphology in a Sample of Overweight and Obese Syrian Women

Objective: Obesity and thyroid nodules are very common. Many studies have reported that weight gain is a new risk factor for goiters and thyroid nodules. In this study, the authors aimed to evaluate thyroid morphology in obese women and tried to link thyroid morphology with anthropometric parameters. Design: A cross-sectional study was conducted between January 2017 and January 2018. Overweight and obese Syrian females, aged >35 years, without past or recent thyroid complaints, and living in the southern region of Syria were included in the study. Weight, height, and hip and waist circumference were measured to calculate anthropometric parameters. Thyroid volume and prevalence of thyroid nodules were compared among BMI groups as defined by World Health Organization classifications. Body Surface Area (BSA), waist circumference (WC), waist:hip ratio, and waist-to-height ratio (WtHR) were compared between nodule groups. Results: A total of 140 overweight and obese females, with a mean age of aged 53±7 years were studied. Mean thyroid volume was 12.4±7.4 mL, with the highest volume identified in the Obesity Class III group (14.9±10.9 mL). Significant positive correlations were found between thyroid volume and weight, BMI, WC, BSA, and WtHR (p<0.05). Thyroid nodule prevalence was 84.3%, and 22.0% of the nodules were fine needle aspiration indicated. Weight and BSA were positively correlated with thyroid nodules (p<0.05), while BMI was not. Conclusion: Thyroid volume was positively correlated with increased weight, BMI, WC, BSA, and WtHR in Syrian females. Positive correlations were found between weight, BSA, and thyroid nodules after age and thyroid stimulating hormone were excluded.

Association Between Thyroid Nodules and Volume and Metabolic Syndrome in an Iodine-Adequate Area: A Large Community-Based Population Study

Background: Given its high incidence, thyroid nodule (TN) warrants public attention. Thyroid volume (TV) has also been associated with multiple factors, such as iodine deficiency and supply and body mass index. It is well known that metabolic syndrome (MetS) comprises many metabolic disturbances, with insulin resistance being its major component. Materials and Methods: The aim of this study was to investigate the relationship between TN and TV and MetS and its components in an iodine-adequate area in Asia. All participants were asked to complete a questionnaire. After excluding 938 individuals based on the exclusion criteria, we reviewed data from 927 of 1865 participants. Adopting MetS diagnostic criteria, we found 437 subjects to be MetS positive [MetS(+)] and 490 subjects to be MetS negative [MetS(-)], respectively. Multivariate linear regression was used to assess the relationship between TNs and MetS. Moreover, univariate binary logistic regression analyses were used to calculate odds ratios (ORs), and 95% confidence intervals (CIs) were used to estimate the associations between different variables and TNs. Results: A total of 232 females and 205 males were MetS(+), as diagnosed using the International Diabetes Federation criteria. However, there were 330 females and 160 males in the group of MetS(-) individuals. The prevalence of TNs was 38.29% in the MetS(+) group and 17.79% in the MetS(-) group. After adjusting for systolic blood pressure, diastolic blood pressure, and gender, only high-density lipoprotein, waist circumference (WC), and age were related to TNs (OR = 0.45, 95% CI 0.27-0.75, P = 0.0023; OR = 1.04, 95% CI 1.02-1.06, P = 0.0036). The TV of all participants was 13.98 (11.24, 17.01) mL; 13.26 (10.62, 16.17) mL for females and 14.96 (11.83, 18.01) mL for males. It was found that only WC was related to TV, after controlling for sex and age (P = 0.02). Conclusions: The morbidity among TN patients in the MetS(+) group was higher than that among the MetS(-) group. High-density lipoprotein cholesterol emerged as a protective factor, and WC was a risk factor for TN. Moreover, TV was related to MetS, and WC was an independent risk factor for TV.

Correlation analysis of metabolic syndrome and its components with thyroid nodules

OBJECTIVE

This study aimed to analyze the relationship between the metabolic syndrome (MetS) and its components with the occurrence of thyroid nodules.

METHODS

A total of 2719 volunteers from some areas of Gansu Province, China, who participated in the national survey of thyroid diseases and iodine nutrition status (Tide) and diabetes prevalence, were selected. Their height, weight, waist circumference (WC), systolic blood pressure (SBP), and diastolic blood pressure were recorded. The fasting plasma glucose (FPG), 2-h plasma postprandial glucose (2hPG), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and glycosylated hemoglobin (HbA1C) levels were measured. The prevalence of MetS and thyroid nodules was evaluated, and the correlation between each component of MetS and thyroid nodules was studied.

RESULTS

The prevalence of MetS and thyroid nodules was 15.4% and 17.2%, respectively. WC, SBP, body mass index, FPG, 2hPG, TG, TC, and thyroid-stimulating hormone levels were significantly higher in the thyroid nodule group. The prevalence of thyroid nodules was significantly higher in the MetS group. A positive correlation was found between the degree of metabolic disorder and the occurrence of thyroid nodules. WC was found to be a risk factor for the occurrence of thyroid nodules. For WC≥90 cm, an increase in the independent variables led to a significant rise in the incidence of thyroid nodules.

CONCLUSION

The prevalence of thyroid nodules was higher in the MetS group. The WC of the MetS components might be an independent risk factor for the occurrence of thyroid nodules.

Thyroglobulin Antibodies are Associated with Symptom Burden in Patients with Hashimoto's Thyroiditis: A Cross-Sectional Study

BACKGROUND

Hashimoto's thyroiditis (HT) is the most common form of autoimmune thyroid disorders characterized by lower production of thyroid hormones and positivity to autoantibodies to thyroglobulin (TgAb) and/or thyroid peroxidase (TPOAb). We performed a comprehensive phenotypic characterization of patients with HT, with specific focus on thyroid autoimmunity, to get better understanding of disease manifestation.

METHODS

We collected information on thyroid-specific phenotypes (TSH, T3, T4, fT4, TgAb, TPOAb, thyroid volume) and other clinical phenotypes (age, body surface area, number of hypothyroidism symptoms, blood pressure) from 290 patients with HT without levothyroxine (LT4) therapy with the aim to test for correlations between thyroid-specific and clinical phenotypes.

RESULTS

Our key and novel finding is the existence of significant positive correlation between TgAb levels and the number of symptoms (r = 0.25, p = 0.0001) in HT patients without LT4 therapy that remained significant after adjustment for TPOAb, T3, TSH levels and thyroid volume (β = 0.66, SE = 0.3, p = 0.0299). Increased TgAb levels are significantly associated with fragile hair (p = 0.0043), face edema (p = 0.0061), edema of the eyes (p = 0.0293) and harsh voice (p = 0.0349).

CONCLUSIONS

Elevated TgAb levels are associated with symptom burden in HT patients, suggesting a role of thyroid autoimmunity in clinical manifestations of HT. Based on these results, we recommend screening for TgAb antibodies in HT patients with symptom burden. We also suggest that further work on understandings of symptoms appearance due to their autoimmune or hypothyroid causation is needed.

Iodine deficiency in pregnancy: Still a health issue for the women of Cassino city, Italy

OBJECTIVE

The World Health Organization, the United Nations Children's Fund, and the International Council for the Control of Iodine Deficiency Disorders recommend a median urinary iodine concentration (UIC) in pregnant women between 150 µg/L and 249 µg/L. In the present study, we evaluated whether in the urban area of Cassino (central Italy), after a national salt iodination program (30 mg/kg) was introduced in 2005, the increased demand of iodine during pregnancy was satisfied.

METHODS

Between January 2016 and April 2017, 99 pregnant women were enrolled to evaluate UIC in spot urine samples, serum level of thyrotropin, free thyroxine, antithyroglobulin and antithyroperoxidase autoantibodies, and thyroid volume by ultrasonography. Eighty clinically healthy non-pregnant women were evaluated as controls.

RESULTS

The median UIC was of 97.7 µg/L and 110.3 µg/L, respectively, in control and pregnant women. A significant increase (P < 0.001) of median thyroid volume was found in pregnant women, relative to control women, being, respectively, 10.4 mL (range 3.68-19.49 mL) and 7.16 mL (range 2.57-14.00 mL). A positive correlation was found between thyroid volume and anthropometric parameters, and an inverse correlation was identified between free thyroxine serum levels and anthropometric parameters.

CONCLUSIONS

This observational study found that the majority of pregnant women and their fetuses appear not to be protected from the detrimental consequences of iodine deficiency. Therefore, the identification of new strategies to increase the knowledge and awareness of the general population regarding the beneficial effects of iodine supplementation during pregnancy is highly required.

Association between lifestyle and anthropometric parameters and thyroid nodule features

PURPOSE

Thyroid nodularity has been associated with obesity, but data regarding associations of body composition parameters with specific ultrasound features of thyroid nodules are lacking. The aim of the present study was to assess associations between thyroid nodule ultrasound characteristics, lifestyle, and anthropometric parameters.

SUBJECTS AND METHODS

This was a cross-sectional study in the general apparently healthy population of Northern Greece. Thyroid ultrasound data together with medical history, demographic, and anthropometric characteristics were individually recorded. Body composition was evaluated using bioelectrical impedance.

RESULTS

Three hundred and six subjects [215 females (70.3%), aged 20-83 years] were included. Ultrasound revealed one or more thyroid nodules in 168 subjects (54.9%). Subjects with thyroid nodules were more frequently females (p = 0.033), older (p < 0.001) and had higher fat mass (p = 0.011), total body fat percentage (p < 0.001) and waist circumference (p = 0.045) than subjects without nodules. In logistic regression analyses, age and female gender were the only independent predictors of presence of thyroid nodules, as well as specific sonographic features. Additionally, total body fat percentage was positively correlated with nodule size (rho = 0.210, p = 0.006) and was the only independent predictor of hypoechoic thyroid nodule(s) and peripheral vascularity, while lack of exercise was predictive of internal vascularity.

CONCLUSIONS

Body fat accumulation and lack of exercise, used as surrogate markers of sedentary lifestyle, influence thyroid nodule size and could predict some ultrasonographic characteristics, like hypoechoicity and internal vascularity. Therefore, routine thyroid examination of obese patients and promotion of active lifestyle may be warranted to prevent thyroid nodule formation and possibly progression to malignancy.

Factors Associated with the Prevalence of Thyroid Nodules and Goiter in Middle-Aged Euthyroid Subjects

The aim of the present study was to determine associations of thyroid hormone levels and different metabolic parameters and anthropometric measurements with volume of nodular and nonnodular thyroid as well as with prevalence of goiter and thyroid nodules in middle-aged euthyroid subjects. Methods. The study consisted of 317 euthyroid subjects aged 48-49 from the Kaunas Cardiovascular Risk Cohort study. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), and antithyroid peroxidase antibody (ATPO) levels, as well as anthropometric and metabolic parameters and smoking information, were evaluated. Results. In subjects with and without thyroid nodules, thyroid volume correlated with components of metabolic syndrome, body mass index (BMI), smoking, and TSH levels. In the nonnodular thyroid group, thyroid volume was also positively related to serum insulin and HOMA-IR, whereas a negative correlation between thyroid volume and leptin was identified in the nodular thyroid group. The goiter was identified in 12.3% of subjects. Female gender, thyroid nodules, smoking, BMI, and levels of TSH were independent predictors for goiter. Thyroid nodules were found in 31.2% of participants. Female gender, higher TSH levels, and thyroid volume were independent risk factors for thyroid nodules. Conclusions. Female gender, thyroid nodules, smoking, BMI, and TSH levels were identified as potential predictors of goiter. Female gender, TSH levels, and thyroid volume predicted the presence of thyroid nodules.

Ultrasonographic assessment of thyroid volume in oldest-old individuals

Objective

The aim of this study was to describe the relationship between thyroid volume and age, gender, anthropometric characteristics, and echogenicity in oldest-old subjects in an iodine-sufficient area.

Subjects and methods

The study included 81 independent elderly individuals aged ≥ 80 years (65 [80.2%] women). We determined these individuals' anthropometric characteristics, body mass index (BMI), and lean body mass, as well as thyroid volume and echogenicity by ultrasonography.

Results

We observed that octogenarians and nonagenarians had different profiles of thyroid echogenicity. The volume of the thyroid was smaller in nonagenarians than octogenarians (p = 0.012, r = 0.176), and subjects aged 80-89 years had more often hypoechoic glands than those aged ≥ 90 years (p = 0.01 versus 0.602).

Conclusion

The identification of ultrasonographic differences in oldest-old individuals will contribute to establishing preclinical markers, such as echogenicity, to identify individuals at risk of developing autoimmune thyroid disease. Future prospective studies should identify if 80-89-year-old individuals with hypoechoic glands progress to hypothyroidism, and if the absence of changes in echogenicity (i.e. a normal thyroid parenchyma) would have a positive impact on longevity among nonagenarians.

Consumption of iodized salt may not represent a reliable indicator of iodine adequacy: Evidence from a cross-sectional study on schoolchildren living in an urban area of central Italy

OBJECTIVE

It has been established that iodine prophylaxis prevents endemic goiter. In this study we reported the amount of iodized salt sold by the retailers of Cassino, a city of central Italy. The aim of the study was to evaluate the effects of an iodine prophylaxis program started in 2005 on urinary iodine concentration (UIC) and thyroid volume (TV), and their correlation with anthropometric parameters in a population of schoolchildren.

METHODS

The study included 234 schoolchildren (119 girls and 115 boys) ages 13 to 14 y. Each student provided a morning urine sample for UIC determination, and TV was evaluated by ultrasonography. Body weight and height also were measured. Each participant completed a questionnaire reporting the presence of thyroid disease and the consumption of iodized salt and iodine-rich food.

RESULTS

The percentage of iodized salt sold by local markets was 42.4%. Median UIC in schoolchildren was 133.9 μg/L (range 33.2-819.5 μg/L), with 71 children having mild (range 50.1-99.9 μg/L) and 10 moderate (range 33.2-48.8 μg/L) iodine deficiency. Eleven children showed excessive iodine intake (range 300.4-819.5 μg/L). Median UIC was higher in children using iodized salt or consuming milk. Goiter prevalence was 3.8%. A positive correlation between TV and body weight, height, and surface was observed.

CONCLUSIONS

The data reported may suggest the presence of an adequate iodine intake in the population of Cassino despite the low percentage of iodized salt sold by local retailers. This indicates that silent iodine prophylaxis through the consumption of iodine-rich or iodine-enriched food is of importance in the prevention of iodine deficiency disorders.