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Oxidative stress may be involved in the progression of hypothyroidism in patients with Hashimoto thyroiditis (HT). Vitamin C is a well-known powerful antioxidant. To our knowledge, whether vitamin C intake relates to hypothyroidism in patients with HT remains unclear. In this cross-sectional study based on the National Health and Nutrition Examination Survey, 2007–2012, we aimed to explore the relationship between total vitamin C intake and hypothyroidism in patients with HT, using multivariate logistic regression models and restricted cubic spline analyses. Our results showed a significant negative linear association between total vitamin C intake (log10-transformed data) and hypothyroidism in HT. Compared with those with the lowest quartile of total vitamin C intake (log10-transformed), participants with the highest quartile were at lower odds of having hypothyroidism (adjusted OR 0·40, 95 % CI: 0·18, 0·88, Ptrend = 0·027). This association was consistent in subgroups stratified by sex (Pfor interaction = 0·084) and age (≥ 60 years and < 60 years, Pfor interaction = 0·330). This study revealed that total vitamin C intake was inversely associated with hypothyroidism among individuals with HT, indicating that higher vitamin C intakes (4·57–1258·9 mg/d) may be associated with a lower likelihood of hypothyroidism among HT participants.
A number of endocrinopathies may complicate pregnancy with significant adverse effects on the mother and fetus. Diagnosis may prove difficult because of a long differential, and pregnancy can mask or mimic signs and symptoms of endocrine disease. Thyroid disease and diabetes are relatively common during pregnancy; however, serious complications such as thyroid storm and diabetic ketoacidosis are rare. Uncommon complications of hyperthyroidism and diabetes are discussed in this chapter along with other rare endocrinopathies
Adherence to prescription medications is critical for both remission from schizophrenia and control of physical comorbidities. While schizophrenia with comorbid hypothyroidism is common, there is little research on adherence to hypothyroidism treatment in this population. The current study used a retrospective, matched case-control design. The cohort included 1,252 patients diagnosed with schizophrenia according to ICD-10 and 3,756 controls matched for gender, age, socioeconomic status and ethnicity without diagnosis of schizophrenia. All data were retrieved from the electronic medical database of a large health maintenance organization. Retrieved data included demographics, thyroid functionality test results and prescribed medications. Measures of adherence to therapy were used for analyses as were data from follow-ups of patients with hypothyroidism. A diagnosis of hypothyroidism was found in 299 patients, 115 of whom were also diagnosed with schizophrenia. The 184 without schizophrenia constituted the control group. No statistically significant differences were found between the two groups regarding prescriptions for L-thyroxin and TSH levels and number of TSH tests. Adherence of patients with schizophrenia to hypothyroidism treatment was found to be as good as that of individuals without a schizophrenia diagnosis.
Emerging evidence suggests that preterm-born individuals (<37 weeks gestation) are at increased risk of developing chronic health conditions in adulthood. This study compared the prevalence, co-occurrence, and cumulative prevalence of three female predominant chronic health conditions – hypertension, rheumatoid arthritis [RA], and hypothyroidism – alone and concurrently. Of 82,514 U.S. women aged 50–79 years enrolled in the Women’s Health Initiative, 2,303 self-reported being born preterm. Logistic regression was used to analyze the prevalence of each condition at enrollment with birth status (preterm, full term). Multinomial logistic regression models analyzed the association between birth status and each condition alone and concurrently. Outcome variables using the 3 conditions were created to give 8 categories ranging from no disease, each condition alone, two-way combinations, to having all three conditions. The models adjusted for age, race/ethnicity, and sociodemographic, lifestyle, and other health-related risk factors. Women born preterm were significantly more likely to have any one or a combination of the selected conditions. In fully adjusted models for individual conditions, the adjusted odds ratios (aORs) were 1.14 (95% CI, 1.04, 1.26) for hypertension, 1.28 (1.12, 1.47) for RA, and 1.12 (1.01, 1.24) for hypothyroidism. Hypothyroidism and RA were the strongest coexisting conditions [aOR 1.69, 95% CI (1.14, 2.51)], followed by hypertension and RA [aOR 1.48, 95% CI (1.20, 1.82)]. The aOR for all three conditions was 1.69 (1.22, 2.35). Perinatal history is pertinent across the life course. Preventive measures and early identification of risk factors and disease in preterm-born individuals are essential to mitigating adverse health outcomes in adulthood.
A 29-year-old primigravida is referred by her primary care provider to your tertiary center’s high-risk obstetrics unit for preconception counseling for known Graves’ disease.
Thyroid dysfunction such as hypothyroidism, is connected with numerous neurological and psychiatric disorders. However, the importance of assessing the interaction between brain, psyche and thyroid in clinical practice is often underestimated, and this has a direct impact on the planning of therapeutic interventions and treatment efficacy in patients with primary hypothyroidism.
Objectives
We examined 132 patients with primary hypothyroidism.
Methods
Assessment of the presence and severity of psychopathology was performed using the technique SCL-90-R (questionnaire severity of psychopathology).
Results
The results showed the highest scores on the scales of somatization (3,75 ± 0,12), depression (3,64 ± 0,13), interpersonal anxiety (3,45 ± 0,19), phobias (3.25 ± 0,31). High rates of somatization scale showing a violation of bodily dysfunction of various body systems-cardiovascular, gastrointestinal, respiratory and headache, muscular discomfort and other unpleasant sensations in different parts of the body and manifest themselves in a complaint of patients. Scale depression revealed the presence of dysphoria, anhedonia, low affect, loss of vitality and interest in life. Relatively high on a scale of phobias indicate the presence in these patients persistent fear responses to certain situations and objects that are irrational and inadequate and lead to avoiding behavior. General index of severity of symptoms (GSI) and the index of an existing symptomatic distress (PSDI) were significantly higher in the following patients than in hypothyroid patients without mental disorders.
Conclusions
Thus, these results should be taken into account when determining treatment strategy both in psychopharmacotherapy and different methods of psychological correction.
Valproate is widely used in the treatment of maniac and mixed episodes and is well known to be safe with side effects being mostly related to hepatic disorders and psychomotor retardation.
Objectives
Raising attention to valproate-induced hypothyroidism that despite the increasing evidence tends to be neglected.
Methods
Here, we report a case of a 55-year-old woman, with a previous diagnosis of schizophrenia, treated for many years with 200mg of zuclopenthixol triweekly and 2mg of risperidone daily. Patient developed a maniac episode characterized by elevated mood, sense of grandiosity, increased energy and psychomotor activity, disinhibition and insomnia. No laboratory abnormalities were detected and inpatient treatment was initiated with paliperidone up to 12mg/day and valproate 1000mg/day.
Results
Patient showed progressive clinical recovery attaining full remission within 2 weeks. Despite the absence of clinical side effects and the valproate serum levels of 74.9μg/mL (range 50–100μg/mL), laboratory testing found progressive reduction F-T4 down to 0.45ng/dL (range 0.8–1.5 ng/dL) and a concomitant upregulation of TSH to 73.99mUI/L (range 0.55–4.8mUI/L). Thyroid autoantibodies and thyroid echography were negative. Considering that patient was previously medicated with risperidone, it was suspected that her hypothyroidism was caused by valproate. Normalization of thyroid function was observed after 21 days valproate withdrawal. Patient is currently being treated with 150 mg paliperidone (monthly) with no recurrence of mood or psychotic episodes and maintain normal thyroid function.
Conclusions
Our case emphasizes the need for extended laboratory testing upon prescription of new pharmacological medications as severe analytic alterations can take place in the absence of immediate clinical manifestation.
Exposure to endocrine-disrupting chemicals during critical windows of development may lead to functional abnormalities in adulthood. Isoflavones are a flavonoid group of phytoestrogens that are recognized by their estrogenic activity and are highly abundant in soybean. Since the thyroid gland presents estrogen receptors and infants, toddlers and teenagers may consume isoflavones from soy-based infant formula and beverages as alternatives to animal milk, we propose to investigate the potential effects of relevant concentrations of soy isoflavones in the regulation of the hypothalamic–pituitary (HP) thyroid axis using peripubertal male rats as an experimental model. Thirty-two 23-day-old male rats were exposed to 0.5, 5, or 50 mg of soy isoflavones/kg from weaning to 60 days of age, when they were euthanized, and the tissues were collected to evaluate the mRNA expression of genes involved in the regulation of the HP thyroid axis and dosages of thyroid hormones (THs). Serum TSH concentrations were increased, while alterations were not observed in serum concentrations of triiodothyronine and thyroxine. Regarding mRNA gene expression, Mct-8 was increased in the hypothalamus, Mct-8, Thra1, and Thrb2 were decreased in the pituitary, and Nis and Pds were reduced in the thyroid. In the heart, Mct8 and Thrb2 were increased, and Thra1 was decreased. In the liver, Mct8, Thra1, and Thrb2 were decreased. These results suggest that the consumption of relevant doses of soy isoflavones during the peripubertal period in males may induce subclinical hypothyroidism, with alterations in the regulation of the HP thyroid axis, modulation of TH synthesis, and peripheral alterations in TH target organs.
The functional differentiation of the mammary gland (MG) is fundamental for the prevention of mammary pathologies. This process occurs throughout pregnancy and lactation, making these stages key events for the study of pathologies associated with development and differentiation. Many studies have investigated the link between mammary pathologies and thyroid diseases, but most have ignored the role of thyroid hormone (TH) in the functional differentiation of the MG. In this work, we show the long-term impact of hypothyroidism in an animal model whose lactogenic differentiation occurred at low TH levels. We evaluated the ability of the MG to respond to hormonal control and regulate cell cycle progression. We found that a deficit in TH throughout pregnancy and lactation induces a long-term decrease in Rb phosphorylation, increases p53, p21, Cyclin D1 and Ki67 expression, reduces progesterone receptor expression, and induces nonmalignant lesions in mammary tissue. This paper shows the importance of TH level control during mammary differentiation and its long-term impact on mammary function.
Psychological symptoms commonly occur as a result of both thyroid and parathyroid disorders. Epidemiological studies evaluating the association between thyroid function and mood are heterogeneous in design and report varying results. The larger studies demonstrate no effect or an increase in depression with decreasing thyroid-stimulating hormone concentrations. There is growing evidence supporting the fact that thyroid function in psychiatric patients may be affected by the mental disorder itself, as well as by the medications used to treat that illness. Biochemical assessment of thyroid function and calcium concentrations should form part of the baseline assessment in those who present with new psychological symptoms. Once an abnormality is confirmed, further workup and treatment of the underlying endocrine disorder can be expected to alleviate and even reverse the psychological symptoms.
The association between lithium and thyroid dysfunction has long been known. Yet it is not known whether lithium-associated hypothyroidism is reversible, once lithium treatment has been stopped.
Objectives
To determine whether lithium-associated hypothyroidism was reversible in patients who subsequently discontinued lithium.
Methods
Retrospective cohort study in the Swedish region of Norrbotten into the effects and side- effects of lithium treatment and other drugs for relapse prevention (LiSIE). For this particular study, we reviewed medical records between 1997 and 2015 of patients treated with lithium.
Results
Of 1340 patients screened, we identified 90 patients with lithium-associated hypothyroidism who subsequently discontinued lithium. Of these, 27% had overt hypothyroidism at the time when thyroid replacement therapy was initiated. The mean delay from lithium start to thyroid replacement therapy start was 2.3 (SD 4.7) years. Fifty percent received thyroid replacement therapy within 10 months of starting lithium. Of 85 patients available for follow up, 35 (41%) stopped thyroid replacement therapy after lithium discontinuation. Six patients reinstated thyroid replacement therapy subsequently. Only one of these had overt hypothyroidism, occurring 13 days after stopping lithium and 11 days after stopping thyroid replacement therapy.
Conclusions
Lithium-associated hypothyroidism seems reversible in most patients, once lithium has been discontinued. In such cases, thyroid replacement therapy discontinuation could be attempted much more often than currently done. Based on the limited evidence of our study, we can expect hypothyroidism to recur early after discontinuation of thyroid replacement therapy if at all.
Disclosure
MO: scient adv. board member Astra Zeneca Sweden; UW: educ. activities Norrbotten Region: Astra Zeneca, Eli Lilly, Janssen, Novartis, Otsuka/Lundbeck, Servier, Shire and Sunovion. All others: none.
Multiple neuroendocrine disorders can present themselves through diverse psychiatric symptoms. In the case of hypothyroidism it can manifest itself through mood disorders that will require a comprehensive differential diagnosis.
Objectives
We present a case report and a review of the relevant literature about the relation between mood disorders and hypothyroidism.
Methods
We present the case of a 56-year-old man with no prior psychiatric record who concurring with a grieving process, developed a depressed mood, fatigue, decreased daily activity, and home isolation for months of evolution. He was diagnosed of hypothyroidism and treated with levotiroxine. It was necessary to boost hormonal treatment with antidepressant drugs due to the persistence of the symptoms after the resolution of the hormonal deficit.
Results
The relationship of depression in patients with overt hypothyroidism is widely recognized. Common alterations to both disorders that could make their diagnosis difficult have been observed: existence of psychomotor slowing, attentional and executive disturbance, anxiety, asthenia, weight gain, depressed mood or bradypsychia among others. In the case of subclinical hypothyroidism, certain neuropsychiatric disorders have been linked without having conclusive evidence.
Conclusions
An early screening of thyroid function at the onset of psychiatric symptoms in individuals without prior psychiatric record is essential in the provision of adequate treatment. Clinical improvement has been seen with hormone replacement therapy alone. However, in up to 10% of patients it becomes insufficient, being necessary to complete it with antidepressant drugs for the complete resolution of the condition.
Сurrent research suggests that the assessment of the quality of life of patients with somatic and mental pathology should be one of the main criteria for assessing the quality of treatmen. Given this view, one of the valid assessment of the performance of integrated mental health and the effectiveness of treatment should be considered as quality of life, defined by WHO. Leading mental health criteria based on such factors as adaptation, socialization and individualization.
Objectives
The aim was to investigate the quality of life of patients with hypothyroidism with non-psychotic mental disorders. We examined 132 patients with hypothyroidism. The age of patients ranged from 25 to 55 years. The main group included 108 patients with non-psychotic mental disorders, which are dominated asthenia (27.78 %), asthenic- depressive (32.41%) and asthenic-anxiety disorders (18.52%). The control group consisted of 24 patients with hypothyroidism without mental disorders.
Methods
Quality of life was assessed using a questionnaire developed by Mezzich, Cohen, Ruiperez, Liu & Yoon (1999), covering the three main components of quality of life: subjective wellbeing/satisfaction, fulfillment of social roles, external living conditions.
Results
Found a significant difference in quality of life in patients with main and control group. The average in the overall perception of life (sense of satisfaction and happiness in general) in the main group was 5.19±1.15, in the control group 7.50±2.25.
Conclusions
The main conclusion is that patients with hypothyroidism really need psychiatric consultation and treatment should include not only endocrinological influence but neuropsychopharmacological and psychological too.
Women with thyroid diseases at the beginning of pregnancy may have suboptimal thyroid hormone levels because of potential difficulties in compensating for the physiological thyroid hormone changes occurring in pregnancy. Our objective was to study the association between preexisting thyroid diseases, pregnancy complications, and neonatal anthropometry. In total, 16,395 women from the ELFE French longitudinal birth cohort were included, and 273 declared pre-pregnancy thyroid diseases. Associations were investigated with multivariable regression models, with adjustment for relevant potential confounders. Body mass index (BMI) was additionally adjusted for in a second stage. As compared with other women, women with pre-pregnancy thyroid diseases were more frequently obese (19.6% vs. 9.8%) and had greater odds of gestational diabetes development (odds ratio [OR] = 1.58 [95% confidence interval [CI] 1.08, 2.30]) or had undergone treatment for infertility (OR = 1.57 [95% CI 1.07, 2.31]). After adjustment for BMI, the association with gestational diabetes was no longer significant (OR = 1.27 [95% CI 0.86, 1.88]). After excluding women with another medical history, those with pre-pregnancy thyroid diseases had increased odds of premature rupture of membranes (OR = 1.51 [95% CI 1.01, 2.25]). Children born from mothers with hypothyroidism before conception due to a disease or as a potential side effect of treatment had a smaller head circumference at birth than other children (β = −0.23 [95% CI −0.44, −0.01] cm). In conclusion, pre-pregnancy thyroid diseases were associated with risk of infertility treatment, gestational diabetes, and premature rupture of membranes. The association between history of hypothyroidism and moderate adverse effects on fetal head circumference growth needs replication.
Thyroid lobectomy is recommended with total laryngectomy for laryngeal cancer in the National Comprehensive Cancer Network (‘NCCN’) guidelines. However, it is associated with a 32–89 per cent risk of hypothyroidism, with or without adjuvant radiotherapy.
Objective
The study aimed to determine whether preserving the whole thyroid, compared to a single lobe, does indeed significantly lower the incidence of hypothyroidism in the setting of total laryngectomy.
Method
A retrospective study was conducted at Groote Schuur Hospital in Cape Town, South Africa.
Results
Eighty-four patients met the inclusion criteria. The overall incidence of hypothyroidism was 45.2 per cent. The incidence of hypothyroidism was significantly reduced in patients who underwent thyroid-sparing total laryngectomy compared to hemithyroidectomy (p = 0.037). Adjuvant radiotherapy was associated with a higher incidence of hypothyroidism (p = 0.001).
Conclusion
Thyroid-preserving laryngectomy should be advocated in carefully selected patients with advanced laryngeal carcinoma, as it reduces the incidence of hypothyroidism.
Abnormal thyroid function is prevalent among women and has been linked to increased risk of chronic disease. Posttraumatic stress disorder (PTSD) has been linked to thyroid dysfunction in some studies; however, the results have been inconsistent. Thus, we evaluated trauma exposure and PTSD symptoms in relation to incident thyroid dysfunction in a large longitudinal cohort of civilian women.
Methods
We used data from 45 992 women from the ongoing Nurses’ Health Study II, a longitudinal US cohort study that began in 1989. In 2008, history of trauma and PTSD were assessed with the Short Screening Scale for Diagnostic and Statistical Manual of Mental Disorders, fourth edition, PTSD, and incident thyroid dysfunction was determined by participants’ self-report in biennial questionnaires of physician-diagnosed hypothyroidism and Graves’ hyperthyroidism. The study period was from 1989 to 2013. Proportional hazard models were used to estimate multivariable-adjusted hazard ratios and 95% confidence intervals (CIs) for incident hypothyroidism and Graves’ hyperthyroidism.
Results
In multivariable-adjusted models, we found significant associations for PTSD only with hypothyroidism [p-trend <0.001; trauma with no PTSD symptoms, 1.08 (95% CI 1.02–1.15); 1–3 PTSD symptoms, 1.12 (95% CI 1.04–1.21); 4–5 PTSD symptoms, 1.23 (95% CI 1.13–1.34); and 6–7 PTSD symptoms, 1.26 (95% CI 1.14–1.40)]. PTSD was not associated with risk of Graves’ hyperthyroidism (p-trend = 0.34). Associations were similar in sensitivity analyses restricted to outcomes with onset after 2008, when PTSD was assessed.
Conclusions
PTSD was associated with higher risk of hypothyroidism in a dose-dependent fashion. Highlighted awareness for thyroid dysfunction may be especially important in women with PTSD.
During the treatment of breast cancer, radiotherapy to the supraclavicular fossa region results in absorption of radiation by the thyroid gland and consequently leads to hypothyroidism in 40% of patients. The aim of this study was to compare thyroid gland radiation absorption during radiotherapy with different anterioposterior beam radiation of 6–15 and 15–15 MV photon beam energies.
Materials and methods
In total, 29 patients with breast cancer were recruited to this study. Adjuvant radiotherapy with a total dose of 50 Gy was performed for each participant. Thyroid gland dosimetric measurements were evaluated including, mean dose, minimum and maximum dose, and V20, V30, V40 and V50 (percentage of thyroid volume receiving ≥20, ≥30, ≥40 and ≥50 Gy, respectively). The irradiation delivered doses were measured using Prowess Panther treatment planning system (Version 5.5). All data were evaluated using SPSS software.
Results
In total, 29 subjects with mean age of 53·4±9·4 were studied. According to the obtained results, at 15–15 MV energies, a significantly lower dose was absorbed by the thyroid gland, was observed in contrast to their counterparts who were treated with 6–15 MV photon beam energies.
Findings
Using 15–15 MV photon beam energies field can significantly reduce the absorbed dose to the thyroid gland and consequently can reduce the risk of developing hypothyroidism in breast cancer patients treated with radiotherapy.
This review attempts to explain why consuming extra myoinositol (Ins), an essential component of membrane phospholipids, is often beneficial for patients with conditions characterised by insulin resistance, non-alcoholic fatty liver disease and endoplasmic reticulum (ER) stress. For decades we assumed that most human diets provide an adequate Ins supply, but newer evidence suggests that increasing Ins intake ameliorates several disorders, including polycystic ovary syndrome, gestational diabetes, metabolic syndrome, poor sperm development and retinopathy of prematurity. Proposed explanations often suggest functional enhancement of minor facets of Ins Biology such as insulin signalling through putative inositol-containing ‘mediators’, but offer no explanation for this selectivity. It is more likely that eating extra Ins corrects a deficiency of an abundant Ins-containing cell constituent, probably phosphatidylinositol (PtdIns). Much of a cell’s PtdIns is in ER membranes, and an increase in ER membrane synthesis, enhancing the ER’s functional capacity, is often an important part of cell responses to ER stress. This review: (a) reinterprets historical information on Ins deficiency as describing a set of events involving a failure of cells adequately to adapt to ER stress; (b) proposes that in the conditions that respond to dietary Ins there is an overstretching of Ins reserves that limits the stressed ER’s ability to make the ‘extra’ PtdIns needed for ER membrane expansion; and (c) suggests that eating Ins supplements increases the Ins supply to Ins-deficient and ER-stressed cells, allowing them to make more PtdIns and to expand the ER membrane system and sustain ER functions.
Hypothyroidism is a common complication when radiotherapy is part of the treatment for head and neck tumours. This study aimed to show the incidence of hypothyroidism and possible risk factors in these patients.
Methods:
Factors related to the population, tumour, treatment and occurrence of hypothyroidism were analysed in 241 patients diagnosed with head and neck carcinoma.
Results:
Approximately 53 per cent of patients were diagnosed with radiation-induced hypothyroidism. Its occurrence was related to: tumour location, laryngeal surgery type, neck dissection type, post-operative complications, cervical radiotherapy and radiotherapy unit type (linear particle accelerator or telecobalt therapy technology).
Conclusion:
Control of thyroid function should be standardised for several years after treatment, particularly in patients with risk factors, such as those treated with telecobalt therapy, those with post-operative complications and for whom the thyroid parenchyma is included in the irradiated area (laryngeal or pharyngeal location and bilateral cervical radiation).
To explore (i) the prevalence of thyroid dysfunction in populations with adequate and excessive iodine intakes and (ii) the effect of iodine exposure on the prevalence of thyroid dysfunction.
Design
Cross-sectional study was conducted in Hebei in 2010. The population was classified as having adequate or excessive iodine intake according to the iodine concentration in drinking water. Demographic information was collected by questionnaire. Levels of serum thyroid hormones, thyroid autoantibodies and iodine in drinking water and urine were measured.
Setting
Villages with adequate or excessive drinking water iodine in Hebei Province, People’s Republic of China.
Subjects
A total of 854 men and women aged 20–50 years who had lived in the surveyed areas for over 5 years, including 348 from the adequate iodine area (AIA) and 506 from the excessive iodine area (EIA).
Results
Median urinary iodine concentration was 185 μg/l in AIA and 1152 μg/l in EIA. The prevalence of thyroid dysfunction in AIA was 10·3 %, which included 1·1 % with hypothyroidism and 8·1 % with subclinical hypothyroidism; and 20·6 % in EIA, which included 3·6 % with hypothyroidism and 13·6 % with subclinical hypothyroidism. The positive rates of thyroglobulin antibody were 16·1 % in AIA and 11·9 % in EIA; the positive rates of thyroperoxidase antibody were 20·7 % in AIA and 16·4 % in EIA.
Conclusions
Excessive iodine intake may lead to increased prevalence of biochemical thyroid dysfunction, especially biochemical hypothyroidism. This is not related to an increase in prevalence of thyroid antibodies. Women are more susceptible to iodine excess.