Prevalence Of Overt Hypothyroidism Research Articles

Serum levels of thyroxine, thyroid-stimulating hormone, and anti-thyroid peroxidase antibodies and their association with anxiety in environmentally exposed populations in Kazakhstan.

Little is known about the impact of environmental pollution on thyroid function in the non-occupationally exposed population of Kazakhstan. This study aimed to investigate serum levels of thyroxine (T4), thyroid-stimulating hormone (TSH), and anti-thyroid peroxidase (TPO) antibodies in the environmentally exposed population of Kazakhstan in relation to symptoms of anxiety. A total of 1,388 nominally healthy individuals residing in areas exposed to three major types of environmental pollution prevalent in Kazakhstan-non-ferrous metallurgy, condensate gas extraction, and activities of the Semipalatinsk Nuclear Test Site (SNTS)-were enrolled. All comparisons were made with 493 individuals residing in settlements without industrial or military pollution. Serum-free T4, TSH, and anti-TPO levels were tested using a solid-phase chemiluminescent immunoassay. The Generalized Anxiety Disorder 7-item (GAD-7) inventory was utilized to screen for anxiety symptoms. The prevalence of subclinical hypothyroidism was significantly higher in residents of settlements near the condensate gas field than in control sites (20.3 vs. 15.0%). In comparison, the prevalence of overt hypothyroidism was insignificantly higher (0.7 vs. 0.6%). The prevalence of subclinical hyperthyroidism was insignificantly higher in residents of settlements around the SNTS. The prevalence of overt hyperthyroidism was insignificantly higher in residents of areas proximal to the condensate gas field compared to the controls. The prevalence of both normal and elevated serum levels of anti-TPO antibodies did not differ significantly between different sites. Moderate and severe anxiety symptoms were the least common in residents of the two control sites (5.9%). This study carries potential implications for tailored public health interventions and policies.

Study of the association between thyroid dysfunction and serum lipid abnormalities.

The prevalence of thyroid dysfunction is increasing, often leading to unfavorable alterations in lipid profiles. Dyslipidemia is a risk factor for cardiovascular disease. The present study aimed to assess the prevalence of thyroid dysfunction and examine its effects on serum lipid profiles among Jordanians. A total of 228 subjects were recruited and divided into two groups: patients with thyroid dysfunction (n=178, mean age=52.6±9.8 years) and a control group (n=50, mean age=51.7±9.2 years). Serum thyroid-stimulating hormone, free thyroxine 4, free triiodothyronine 3, total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein and triglycerides (TG) were measured. Results showed that thyroid dysfunction was diagnosed in 75% of participants, with an increased frequency among females. The prevalence of overt hypothyroidism was 17.4%, subclinical hypothyroidism was 43.8%, overt hyperthyroidism was 18.4% and subclinical hyperthyroidism was 20.4%. There was a significant association between hypothyroidism and elevated TC (>200 mg/dl), LDL (>130 mg/dl) and TG (>200 mg/dl; P<0.05). Among the hypothyroid patients, 48.4% had hypercholesterolemia and 32.3% had hypertriglyceridemia. In conclusion, public screening and education are necessary to combat thyroid dysfunction. There is a notable link between thyroid dysfunction and lipid abnormalities, necessitating regular monitoring for dyslipidemia and cardiovascular disease in affected patients.

Study on the Relationship Between Serum Iodine and Thyroid Dysfunctions: a Cross-Sectional Study.

The relationship between serum iodine (SIC) and thyroid dysfunctions in adults is poorly understood, and this study aimed to explore their relationship. A total of 1320 participants were included in the final analysis. We collected basic demographic information, blood, and spot urine samples to determine serological indices and iodine nutritional status. The median (IQR) of urinary iodine (UIC)/urinary creatinine (UCr), UIC, SIC were 138.1 (91.1, 207.6) μg/g, 155.8 (94.5, 211.1) μg/L, and 70.6 (59.8, 83.9) μg/L, respectively. The 90% reference ranges for UIC/UCr and SIC were 66.5-349.8mg/g and 49.3-97.1μg/L. SIC was positively correlated with UIC and UIC/UCr. The prevalence of overt hypothyroidism and subclinical hypothyroidism in female was significantly higher than that in male (P = 0.02, P = 0.002). In male, subjects above the upper reference value of SIC (97.1μg/L) had a higher risk of subclinical hyperthyroidism (OR = 4.46, 95% CI: 1.29, 12.8) and overt hypothyroidism (OR = 5.59, 95% CI: 1.88, 6.42). In female, subjects below the lower reference value of SIC (49.3μg/L) had a higher risk of overt hypothyroidism (OR = 2.18, 95% CI: 1.10, 4.06), TgAb positive (OR = 1.97, 95% CI: 1.15, 3.32) and TPOAb positive (OR = 2.48, 95% CI: 1.41, 4.26). In conclusion, serum iodine can be used as an indicator to evaluate iodine nutritional status and thyroid dysfunctions. Higher serum iodine concentration was associated with an increased risk of subclinical hyperthyroidism and overt hypothyroidism in men; lower serum iodine concentration was associated with an increased risk of overt hypothyroidism and positive TgAb and TPOAb in women.

Relationships between the serum TPOAb and TGAb antibody distributions and water iodine concentrations, thyroid hormones and thyroid diseases: a cross-sectional study of 2503 adults in China.

The aim of this study was to explore the status of thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TGAb) in three areas with differing water iodine concentrations; and to discuss the relationships between these two thyroid antibodies and thyroid diseases in the three areas. We investigated 2503 adults from three areas. Urinary iodine concentrations, thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), TPOAb, TGAb and thyroid volume (TV) were measured, and thyroid ultrasonography was performed. The positivity rates of TGAb(+), TPOAb(+) and TGAb(+) and TPOAb(+) or TGAb(+) were significantly higher in iodine fortification (IF) areas than iodine adequate (IA) areas (all P < 0·05). In IF and iodine excess areas, the positivity rates of TPOAb(+), TGAb(+) and TPOAb(+) or TGAb(+) significantly increased with age (all P for trend < 0·05). The levels of TSH, TV and the prevalence of overt hypothyroidism, subclinical hypothyroidism and goitre were significantly elevated in the thyroid antibody-positive groups in the three areas, but the FT3 was diminished (all P < 0·010). Positivity for TPOAb and TGAb was associated with an increased risk of subclinical hypothyroidism in the three areas. In areas with different median water iodine, positivity for both TPOAb and TGAb was associated with elevated TSH values. Notably, with the increased levels of TPOAb, the frequency of abnormally elevated TSH increased dramatically in the three areas.

The Prevalence of Thyroid Dysfunction in Korean Women Undergoing Routine Health Screening: A Cross-Sectional Study.

Background: Women are more likely to experience thyroid diseases than men. However, thyroid dysfunction risk in women undergoing the menopausal transition remains largely unknown. We explored the prevalence of thyroid dysfunction across menopausal stages. Methods: We conducted a cross-sectional study of 53,230 women aged 40 years or older who underwent health screening between 2014 and 2018. Menopausal stages were categorized into 4 based on the Stages of Reproductive Aging Workshop +10 criteria. A multinomial logistic regression model was used to estimate the prevalence ratios (PRs) with confidence intervals [CIs] for thyroid dysfunction in menopausal stages compared with that in premenopause. Results: The prevalence of overt hypothyroidism was significantly increased during late transition and postmenopause; it remained significant after further adjustments for potential confounders (age, center, year of examination, age at menarche, parity, education level, smoking status, alcohol consumption, physical activity, and body mass index) with corresponding multivariable-adjusted PRs [CI] of 1.61 [1.12-2.30] and 1.66 [1.16-2.37] in the late transition and postmenopausal stages, respectively. A significant increase in the prevalence of subclinical hypothyroidism was also observed in the late transition and postmenopausal stage with multivariable-adjusted PRs [CI] of 1.22 [1.06-1.40] and 1.24 [1.07-1.44], respectively. In contrast, subclinical and overt hyperthyroidism were not significantly associated with menopausal stages. Conclusions: In this study of pre- and perimenopausal Korean women, the prevalence of overt and subclinical hypothyroidism was significantly elevated in the late menopausal transition. Future prospective studies are warranted to investigate the clinical and prognostic significance of thyroid dysfunction in women during menopausal transition.

Seronegative phenotype in a pediatric population with Hashimoto's thyroiditis.

The aim was to verify in a pediatric population with Hashimoto's thyroiditis whether there is a relationship between antithyroid antibodies and inflammatory status on thyroid ultrasound and thyroid function. A total of 154 children and adolescents, aged 4 to 18years, diagnosed with Hashimoto's thyroiditis with normal body weight were followed up for 1year. Patients with only antiperoxidase antibodies presented with higher TSH levels than subjects with only antithyroglobulin antibodies (p 0.027) but with similar FT4 levels and thyroid score. Prevalence of seronegative Hashimoto's thyroiditis in this cohort was 12.3% (19/154). At diagnosis, the seronegative group presented with lower prevalence of overt hypothyroidism, symptoms of hypothyroidism, and thyroid score, meaning less severe thyroid involvement. In contrast, similar TSH and FT4 values were found at diagnosis and during follow-up in both the seronegative and seropositive groups. A comparison between patients with seronegative Hashimoto's thyroiditis and an overweight/obese antibody-negative population, who presented superimposable altered parenchymal pattern on thyroid ultrasound without circulating antithyroid antibodies, presented similar clinical data. We report for the first time in the literature that seronegative Hashimoto's thyroiditis in the pediatric age group has a less severe pattern. The seronegative group presents similar characteristics to those of overweight/obese children and adolescents with ultrasound changes, but, according to the established knowledge, the latter condition is reversible and does not need follow-up examinations.

Association of Subclinical Hypothyroidism with Nonalcoholic Fatty Liver Disease in Patients with Type 2 Diabetes Mellitus: A Cross-Sectional Study.

Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) are recognized as two common health problems. Metabolic diseases, such as dyslipidemia, obesity, and hypertension are known risk factors for NAFLD. In addition to these risk factors, other risk factors have been recently suggested, such as thyroid dysfunction. In this study, adult patients with T2DM were recruited. Various clinical and biochemical parameters including thyroid function tests, liver function tests, and liver sonography in all participants were assessed and compared between with and without NAFLD groups. Data from 926 diabetic patients were analyzed; of which, 744 (80.3%) had fatty liver. The prevalence of subclinical hypothyroidism (SCH) in patients with NAFLD was 11.6% and in patients without NAFLD was 6.0% (P = 0.029). Furthermore, the prevalence of overt hypothyroidism was higher in diabetic patients with NAFLD (3.9% vs. 1.6%); this difference was not statistically significant. In univariate logistic regression analysis, hemoglobin A1c (odds ratio [OR]: 8.13); history of insulin consumption (OR: 5.35); duration of diabetes (OR: 2.20); family history of diabetes (OR: 2.85); history of antihypertensive drug use (OR: 2.14) as well as SCH (OR: 2.03) were significant variables for NAFLD. According to the multivariate logistic model, after eliminating the confounding effect of age, sex, and body mass index; the chance of developing NAFLD in patients with SCH was 2.32 times higher than patients without SCH (P = 0.014). NAFLD is extremely common in patients with T2DM. The relationship between hypothyroidism and NAFLD is independent of other risk factors.

The Prevalence of Metabolic and Endocrine Disorders Among HIV-infected Patients in a Population From the South of Iran

Background: Since the beginning of the acquired immunodeficiency syndrome (AIDS) pandemic, the number of people infected with human immunodeficiency virus (HIV) has shown a steady increase. Previous evidence exists regarding the evaluation of endocrine dysfunction in HIV-infected individuals. The present study sought to investigate the prevalence of metabolic and endocrine disorders in HIV-positive patients. Materials and Methods: In this cross-sectional study, 72 HIV-positive patients supported by the Behavioral Diseases Center of Bandar Abbas, Iran were recruited from April, 2016 to September, 2017. Patients who did not consent to participate were excluded from the study. Several parameters were measured, including serum free T3, free T4, thyroid-stimulating hormone (TSH), luteinizing hormone (LH), adrenocorticotropic hormone (ACTH), free testosterone, cortisol, fasting plasma glucose (FPG), 2-hour plasma glucose, cholesterol, triglyceride, and low- and high-density lipoprotein levels. Finally, data were analyzed using chi-square and Mann-Whitney tests. Results: High serum lipoprotein levels, diabetes, and prediabetes were observed in 28/72 (38.9%), 13/72 (18.1%), and 17/72 (23.6%) patients, respectively. The prevalence of overt hypothyroidism and subclinical hypothyroidism, as well as overt hyperthyroidism and subclinical hyperthyroidism was 32.8% (22/67), 9% (6/67), 1.5% (1/67), and 7.5% (5/67), respectively. Primary and secondary gonadal dysfunction were found in 1/47 (2.1%) and 9/47 (19.1%) patients, respectively. Primary and secondary adrenal insufficiency were detected in 8/53 (15.1%) and 1/53 (1.9%) patients, respectively. Diabetes was significantly more frequent among older patients and those with a history of addiction. Conclusions: The results of this study indicated a relatively high frequency of metabolic and endocrine disorders, especially dyslipidemia and hypothyroidism in HIV-positive patients.

Reference Intervals for Thyroid-Associated Hormones and the Prevalence of Thyroid Diseases in the Chinese Population.

BackgroundThyroid diseases are highly prevalent worldwide, but their diagnosis remains a challenge. We established reference intervals (RIs) for thyroid-associated hormones and evaluated the prevalence of thyroid diseases in China.MethodsAfter excluding outliers based on the results of ultrasound screening, thyroid antibody tests, and the Tukey method, the medical records of 20,303 euthyroid adults, who visited the Department of Health Care at Peking Union Medical College Hospital from January 2014 to December 2018, were analyzed. Thyroid-associated hormones were measured by the Siemens Advia Centaur XP analyzer. The RIs for thyroid-associated hormones were calculated according to the CLSI C28-A3 guidelines, and were compared with the RIs provided by Siemens. The prevalence of thyroid diseases over the five years was evaluated and compared using the chi-square test.ResultsThe RIs for thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), total thyroxine (TT4), and total triiodothyronine (TT3) were 0.71–4.92 mIU/L, 12.2–20.1 pmol/L, 3.9–6.0 pmol/L, 65.6–135.1 nmol/L, and 1.2–2.2 nmol/L, respectively. The RIs of all hormones except TT4 differed significantly between males and females. The RIs of TSH increased with increasing age. The prevalence of overt hypothyroidism, overt hyperthyroidism, subclinical hypothyroidism, and subclinical hyperthyroidism was 0.5% and 0.8%, 0.2% and 0.6%, 3.8% and 6.1%, and 3.3% and 4.7% in males and females, respectively, which differed from those provided by Siemens.ConclusionsSex-specific RIs were established for thyroid-associated hormones, and the prevalence of thyroid diseases was determined in the Chinese population.

Prevalences of subclinical and overt hypothyroidism with universal screening in early pregnancy.

To reveal the prevalence of subclinical and overt hypothyroidism among Turkish population during pregnancy. Also to investigate the prevalence of hypothyroidism using ATA 2017 criteria. This is a cross-sectional study. Patients were consisted of 1416 consecutive pregnant women who were universally screened for thyroid disease in their first trimester between 2013 and 2015. Thyroid-stimulating hormone (TSH) and free T4 (FT4) levels were analyzed during the first antenatal visit (before 12weeks of gestation). We compared different cutoffs for TSH. We further determined the 2.5th and 97.5th percentiles for TSH and FT4. Initially, the cutoff of 2.5IU/ml was selected. Accordingly, 305 women (22.3%) had subclinical hypothyroidism and 22 (1.6%) was diagnosed with overt hypothyroidism. When the cutoff was increased to 4IU/ml, only 40 (2.9%) women were diagnosed with hypothyroidism. Prevalences of overt hypothyroidism and subclinical hypothyroidism were 0.6% and 2.3%, respectively. Universal screening of pregnant women with TSH, using the 2.5mIU/L cutoff; one in four women was found to be a candidate for thyroid hormone replacement in our cohort. When the cutoff was determined to be 4mIU/L, prevalence of hypothyroidism decreased approximately 10 times.

A Cross-Sectional Study to Assess the Prevalence of Adult Thyroid Dysfunction Disorders in Jordan.

Background: Insufficient production of thyroid hormones results in hypothyroidism, while overproduction results in hyperthyroidism. These are common adult disorders, with hypothyroidism more common in the elderly. Jordan has had past problems with dietary iodine deficiency but there are no published studies assessing the population prevalence of these disorders in the Arab Middle East. Methods: A cross-sectional study was conducted in three representative areas of Jordan. There were 7085 participants with a mean age of 40.8 years. Participants completed a questionnaire and had blood taken for thyroid analysis. Results:Hypothyroidism: The prevalence of any hypothyroidism (already diagnosed and/or identified by blood testing) was 17.2% in females and 9.1% in males. Undiagnosed prevalence was 8% and 6.2% for females and males, respectively. The prevalence of subclinical hypothyroidism, defined as high serum thyrotropin (TSH) and normal serum-free thyroxine (fT4), was 5.98% among females and 4.40% among males. The prevalence of overt hypothyroidism, defined as high TSH and low fT4, was 2.00% among females and 1.80% among males. Only 53.5% (55.3% for females, 42.1% males) of those previously diagnosed with hypothyroidism had TSH levels within the appropriate range. Hyperthyroidism: The prevalence of any hyperthyroidism (already diagnosed and/or identified by blood testing) was 1.8% in females and 2.27% in males. The undiagnosed prevalence was 1.4% and 2.1% for females and males, respectively. The prevalence of subclinical hyperthyroidism (low TSH and normal fT4) was 1.20% and 1.80% among males and females accordingly. The prevalence of overt hyperthyroidism (low TSH and high fT4) was 0.2% among females and 0.3% among males. About 85.7% (83.3% for females, 100% males) of those previously diagnosed with hyperthyroidism had TSH levels within the appropriate range. Conclusions: The results of this study reveal that the total prevalence of thyroid dysfunction among adult females and males in Jordan is very high compared with international statistics, particularly in the rates of undiagnosed cases. This indicates the need for further assessment of the value of screening for adult hypothyroidism in Jordan.

Prevalence of iatrogenic hypothyroidism in hyperthyroid cats treated with radioiodine using an individualised scoring system.

The aim of this study was to report the prevalence of iatrogenic hypothyroidism, with or without azotaemia, based on the measurement of serum total thyroxine (T4), thyroid-stimulating hormone (TSH) and creatinine concentrations, in hyperthyroid cats undergoing radioiodine (131I) treatment where the 131I dose was calculated using a previously described scoring system. A secondary aim of the study was to determine the positive and negative predictive values of serum T4 and TSH concentrations obtained 19 days after treatment in order to predict the development of iatrogenic hypothyroidism 6-9 months after 131I treatment. Serum T4, TSH and creatinine concentrations were measured 19 days and 6-9 months after 131I treatment. The prevalence of iatrogenic hypothyroidism was assessed with the results obtained 6-9 months after 131I treatment. The prevalence of overt and subclinical hypothyroidism 6-9 months after 131I treatment was 40.0% (22/55 cats) and 12.7% (7/55 cats). Overt hypothyroidism with azotaemia was diagnosed in 8/55 (14.5%) cats. The positive and negative predictive values for the prediction of the development of iatrogenic hypothyroidism 6-9 months after 131I treatment were 72.2% and 80.0%, respectively, for a low serum T4 concentration, and 75.0% and 44.6%, respectively, for an increased serum TSH concentration. The use of an individualised scoring system is effective in determining the 131I dose for the treatment of hyperthyroid cats. However, the prevalence of overt hypothyroidism was higher in comparison with other studies using different dosing protocols. Further studies comparing the efficacy of individualised scoring systems and different fixed doses to determine which method is superior are warranted.

Validation of Billewicz Scoring System for Detection of Overt Hypothyroidism During Pregnancy.

BackgroundCurrently, various clinical and laboratory diagnostic methods are used to detect overt hypothyroidism during pregnancy. The Billewicz scoring index, as a clinical scale for detection of hypothyroidism, has been applied in general populations; however, its application during pregnancy remains a controversial subject of ongoing research.ObjectivesThe purpose of this study was to evaluate the diagnostic value of Billewicz scoring index for overt hypothyroidism in a general population of Iranian pregnant women.MethodsThis study was conducted on 1843 pregnant women. A comprehensive questionnaire, including Billewicz scoring items, was completed, and relevant clinical examinations were performed. The participants underwent serum measurements of thyroxine (T4), thyroid hormone uptake, thyroid-stimulating hormone (TSH), and thyroid peroxidase antibody (TPOAb). Using the receiver operating characteristic (ROC) curve analysis, the optimal sensitivity and specificity were determined as values with maximum yields on the Youden and Rsquo’s Index (sensitivity + specificity-1).ResultsThe prevalence of overt hypothyroidism and subclinical hypothyroidism was 3.3% and 28.6%, respectively. Overall, 3.6%, 18.9%, and 50% of euthyroid, subclinical hypothyroid, and overt hypothyroid women were TPOAb-positive, respectively. The mean Billewicz scores of euthyroid, overt hypothyroid, and subclinical hypothyroid women were -41.16 (11.16), -17.11 (13.63), and -40.1 (11.2), respectively. Based on the Billewicz scale, at least one sign of hypothyroidism was reported in 38.84% (n, 491) of euthyroid women. Scores ≤ -26.5 (sensitivity, 100%; specificity, 90.82%) were considered as the optimal scores for predicting overt hypothyroidism (Ldquo, Norisk, and Rsquo).ConclusionsThe Billewicz clinical scoring system, as a reliable and inexpensive clinical tool, used along with laboratory measurements, can help screen overt hypothyroidism during pregnancy, primarily in low-resource settings.

Prevalence of hypothyroidism in Assam: A clinic-based observational study

Introduction: Hypothyroidism is a common functional disorder of the thyroid gland. Despite extensive research, data on this subject are lacking from the northeastern part of India, which falls in the Sub-Himalayan goitrogenic belt. Therefore, we decided to study the profile of hypothyroidism in Assam, a northeastern state with the following objectives: to determine the prevalence of hypothyroidism and to describe the various modes of clinical presentation. Materials and Methods: The study was conducted at a clinic-cum-radioimmunoassay laboratory in Guwahati, Assam, from January to November 2011. Two thousand and four hundred fifty-six patients referred to our center from different parts of Assam were evaluated clinically and their thyroid profile was estimated. Antithyroid peroxidase (TPO) antibody was estimated in 1950 patients. Results: The prevalence of overt hypothyroidism was 10.9% (n = 267) and that of subclinical hypothyroidism was 13.1% (n = 321). Male:female ratio was 1:3. Among the cases of overt hypothyroidism, 247 (92.51%) were adult hypothyroids, 15 (5.62%) juvenile hypothyroids, and 5 (1.87%) cretins. The common presenting features of hypothyroidism were weakness (98%), lethargy (95%), dry and coarse skin (87%), and body ache (85%). Uncommon modes of presentation were pleural and pericardial effusion, low body weight, frequent motions, and palpitations. Postthyroidectomy and drug-induced hypothyroidism accounted for 2.38% cases each and postpartum hypothyroidism for 3.74% cases. Thirteen percent cases presented with goiter. The prevalence of anti-TPO antibody in the study population was 8.41%. Conclusion: Hypothyroidsm is no longer a rarity, and Assam is no exception to this phenomenon. A population-based epidemiological study of thyroid disorders in Northeast India is an urgent need.

High prevalence of antithyroid peroxidase and antiparietal cell antibodies among patients with type 1 diabetes mellitus attending a tertiary diabetes centre in South Africa

ObjectiveData on the prevalence of autoimmune thyroid disease (AITD) and gastric autoimmunity in type 1 diabetes mellitus (T1DM) in Africa are limited. The aim of this study was to assess...

Incidence and prevalence of overt hypothyroidism and causative diseases in Korea as determined using claims data provided by the health insurance review and assessment service

Incidence and prevalence of overt hypothyroidism and causative diseases in Korea as determined using claims data provided by the health insurance review and assessment service

Malabsorption of L-T4 Due to Drip Coffee: A Case Report Using Predictors of Causation

Levothyroxine, also known as L-thyroxine or L-T4, is a synthetic hormone commonly used to replace endogenous thyroid hormone in patients with primary or central hypothyroidism. The prevalence of overt hypothyroidism, defined herein as serum thyroid-stimulating hormone (TSH) above 4.5 mU/L, is 0.3% in the United States. 1 Jonklaas J. Bianco A.C. Bauer A.J. et al. Guidelines for the treatment of hypothyroidism: prepared by the American Thyroid Association task force on thyroid hormone replacement. Thyroid. 2014; 24: 1670-1751 Crossref PubMed Scopus (894) Google Scholar , 2 Hollowell J.G. Staehling N.W. Flanders W.D. et al. Serum TSH, T(4), and thyroid antibodies in the United States population (1988 to 1994): National Health and Nutrition Examination Survey (NHANES III). J Clin Endocrinol Metab. 2012; 87: 489-499 Crossref Scopus (2960) Google Scholar Monotherapy of L-T4 is one of the most commonly used therapies for treatment of hypothyroidism and is consistently among the top 200 medications dispensed in the United States. 1 Jonklaas J. Bianco A.C. Bauer A.J. et al. Guidelines for the treatment of hypothyroidism: prepared by the American Thyroid Association task force on thyroid hormone replacement. Thyroid. 2014; 24: 1670-1751 Crossref PubMed Scopus (894) Google Scholar L-T4 should be taken as a single daily dose in the morning on an empty stomach, preferably 30 to 60 minutes before food. 3 Synthroid [package insert]. AbbVie Inc, North Chicago, IL2012 Google Scholar , 4 Levothyroxine [package insert]. Mylan Pharmaceuticals Inc, Morgantown, WV2010 Google Scholar , 5 Bach-Huynh T.G. Nayak B. Loh J. Soldin S. Jonklaas J. Timing of levothyroxine administration affects serum thyrotropic concentration. J Clin Endocrinol Metab. 2009; 94: 3905-3912 Crossref PubMed Scopus (134) Google Scholar , 6 Bolk N. Visser T.J. Numan J. Jongste U. Tussen J.G. Berghout A. Effects of evening vs. morning levothyroxine intake: A randomized double-blind crossover trial. Arch Intern Med. 2010; 170: 1996-2003 Crossref PubMed Scopus (97) Google Scholar Package inserts for L-T4 in the United States do not currently include coffee in the list of compounds that interact with L-T4, although this interaction is noted in clinical practice guidelines. 1 Jonklaas J. Bianco A.C. Bauer A.J. et al. Guidelines for the treatment of hypothyroidism: prepared by the American Thyroid Association task force on thyroid hormone replacement. Thyroid. 2014; 24: 1670-1751 Crossref PubMed Scopus (894) Google Scholar , 3 Synthroid [package insert]. AbbVie Inc, North Chicago, IL2012 Google Scholar , 4 Levothyroxine [package insert]. Mylan Pharmaceuticals Inc, Morgantown, WV2010 Google Scholar

Incidence and Prevalence of Overt Hypothyroidism and Causative Diseases in Korea as Determined Using Claims Data Provided by the Health Insurance Review and Assessment Service.

BackgroundThe incidence and prevalence of overt hypothyroidism have been reported to be 2 to 4/1,000 population/year and 8 to 13/1,000 population, respectively, in foreign countries. As there has been no nationwide survey to obtain data in Korea, the present study investigated the incidence and prevalence of overt hypothyroidism in Korea using claims data provided by the Health Insurance Review and Assessment Service. The proportions of causative diseases for hypothyroidism were also analyzed.MethodsThis study was retrospectively performed with 541,969 Korean patients (92,832 men and 449,137 women), with overt hypothyroidism, treated with thyroid hormone between 2008 and 2012.ResultsThe incidence of overt hypothyroidism in Korea was 2.26/1,000 population/year (0.78 in men and 3.72 in women), and the prevalence was 14.28/1,000 population (4.40 in men and 24.03 in women). When patients with thyroid cancer were excluded, the incidence was 1.56/1,000 population/year (0.54 in men and 2.57 in women). The incidence increased with age, with peaks in and after the late 60s in men and in the early 50s in women. The prevalence peaked in the early 70s in men and in the late 50s in women.ConclusionThis is a report of the first nationwide investigation of the incidence and prevalence of overt hypothyroidism in Korea, although it is limited to patients treated with thyroid hormone.

A hospital-based study of prevalence of thyroid dysfunction in Srinagar, Jammu and Kashmir state of India

Background: Significant incidence of thyroid dysfunction, especially hypothyroidism, has been reported in Kashmir Valley of India. There is a paucity of studies that assessed the presence of thyroid dysfunction in various age groups of people in Srinagar. Objectives: This study aimed to investigate the prevalence of thyroid dysfunction in the local population who visit the outpatient department of Ramakrishna Mission Clinic at Srinagar. Materials and Methods: This work is a cross-sectional study carried out for 18 months. The study subjects were the patients who attended outpatient department of Ramakrishna Mission Clinic; patients referred by private practitioners of Srinagar and adjoining areas. The data were from those subjects who got thyroid function tests done for the first time. Thyroid function was assessed by clinical examination and thyroid function tests (T3, T4, and TSH). Results: The total number of subjects tested for thyroid function was 612 of which 120 were men and 492 were women. Total prevalence of thyroid disorders in the study population was 40.36% (247 of 612). Of the total 247 subjects with thyroid disorders, 17.8% were men (44) and 81.2% were women (203). Overall prevalence of subclinical hypothyroidism was 33% (206 of 612); prevalence of overt hypothyroidism was 5% (31 of 612); and prevalence of hyperthyroidism was 1.6% (10 of 612). Conclusion: There is a high prevalence of thyroid disorders in Kashmir population, and subclinical hypothyroidism is the most prevalent thyroid disorder. In females, maximum prevalence of subclinical hypothyroidism is seen in the reproductive age group.

High prevalence of maternal hypothyroidism despite adequate iodine status in Indian pregnant women in the first trimester.

Iodine requirements are increased during pregnancy to maintain maternal and fetal euthyroidism. There have been recent improvements in iodized salt coverage in India, but whether iodized salt is sufficient to sustain iodine requirements during pregnancy remains uncertain. Our aims were to measure thyroid status in first trimester pregnant women in southern India and assess potential determinants of thyroid function, including iodine status, thyroid autoimmunity, dietary patterns, body weight, and anemia. This was a cross-sectional study among 334 pregnant women of ≤ 14 weeks' gestation, in Bangalore, India. We measured anthropometrics, urinary iodine concentration (UIC), maternal thyroid volume (by ultrasound), and thyroid function. We applied a thyrotropin (TSH) upper limit of 2.5 mIU/L to classify thyroid insufficiency. Using a questionnaire, we obtained sociodemographic and dietary data, obstetric history, and use of iodized salt and iodine supplements. Among the women, the mean (standard deviation) gestational age was 10.3 (2.5) weeks, 67% were nulliparous, 21% were vegetarian, 19% were anemic, and 23% were overweight or obese. Iodized salt was used by 98% of women, and they were iodine sufficient: median UIC (range) was 184.2 μg/L (8.1-1152 μg/L) and all had a normal thyroid volume. However, 18% of the women had thyroid insufficiency: 3.7% had overt hypothyroidism (83% with positive TPO-Ab), 9.2% had subclinical hypothyroidism, and 5.2% had hypothyroxinemia. Women consuming vegetarian diets did not have significantly lower iodine intakes or higher risk of hypothyroidism than those consuming mixed diets, but overweight/obesity and anemia predicted thyroid insufficiency. In this urban population of southern India, pregnant women have adequate iodine status in the first trimester. Despite this, many have thyroid insufficiency, and the prevalence of overt hypothyroidism is more than fivefold higher than reported in other iodine sufficient populations of pregnant women.