Prevalence of Subclinical Hyperthyroidism in adults with Hypertension

Introduction@#Hypertension in adult Filipinos is a significant concern for its increasing number (overall prevalence: 22.3). Percentage of thyroid function abnormalities is 8.53% with the greatest proportion of volunteers having subclinical thyroid disease. To our knowledge, there is no available Filipinobased study on hypertension and subclinical hyperthyroidism. The study aims to determine the prevalence of subclinical hyperthyroidism in adults with hypertension. It also aims to determine the difference among age groups and gender with subclinical hyperthyroidism and hypertension. @*Methods@#This was a prospective cross-sectional prevalence study. Minimum sample size was computed at 80 but total sample taken was 98. Study population was taken from January 2019 to May 2019. All hypertensive patients with thyroid function test done in a nuclear medicine section in a tertiary institution were included. This study utilized prevalence rate. To determine the difference between age groups of patients with subclinical hyperthyroidism and hypertension, age groups were treated as follows: late adolescence (18–24), early adulthood (25–34), middle adulthood (35–60), late adulthood (61–75), very old age (76+). Significant difference of prevalence rate for each age group and gender was determined using analysis of variance and t-test respectively. @*Results@#The over-all prevalence of subclinical hyperthyroidism in hypertensive patients is 13.13% with most prevalence on late adolescence and male population (25% and 17.65% respectively). @*Conclusion@#An increase in vigilance with thyroid disorders, especially subclinical hyperthyroidism might be warranted more in males in 18 to 24 years of age. An updated Filipino-based, or a larger Asian-based guideline which will encompass a larger population is needed, due to an increase in migration in this region. This Asian-based guideline will benefit healthcare standards in hypertensives in this region.

Evaluation of redox profiles in exogenous subclinical hyperthyroidism at two different levels of TSH suppression

ABSTRACT Objective: Evaluate the relationship between exogenous subclinical hyperthyroidism and oxidative stress through the analysis of the redox profile of patients with subclinical hyperthyroidism exogenous (SCH) grade I (TSH = 0.1 to 0.4 IU/mL) and grade II (TSH < 0.1 IU/mL). Subjects and methods: We analyzed 46 patients with SCH due to the use of TSH suppressive therapy with LT4 after total thyroidectomy along with 6 control euthyroid individuals (3M and 3W). Patients were divided into two groups, G1 with TSH ≥ 0.1-0.4 IU/mL (n = 25; and 7M 14W) and G2 with TSH < 0.1 IU/mL (n = 25; and 4M 21W). Venous blood samples were collected to measure the levels of markers for oxidative damage (TBARS, FOX and protein carbonylation), muscle and liver damage (CK, AST, ALT, GGT) and antioxidants (GSH, GSSG and catalase). Results: Individuals in G2 showed a GSH/GSSG ratio ~ 30% greater than those in G1 (p = 0.004) and a catalase activity that was 4 times higher (p = 0.005). For lipid peroxidation, the levels measured in G2 were higher than both control and G1 (p = 0.05). No differences were observed for both protein carbonyl markers. G1 and G2 presented with greater indications of cell injury markers than the control group. Conclusion: TSH suppression therapy with LT4 that results in subclinical hyperthyroidism can cause a redox imbalance. The greater antioxidant capacity observed in the more suppressed group was not sufficient to avoid lipid peroxidation and cellular damage.

Relationship between heart rate variability and subclinical thyroid disorders of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

The association between subclinical thyroid dysfunctions and autonomic modulation changes has been described by many studies with conflicting results. We aimed to analyze the association between subclinical hyperthyroidism (SCHyper), subclinical hypothyroidism (SCHypo), and heart rate variability (HRV) using the baseline from ELSA-Brasil. SCHyper and SCHypo were classified by use of medication to treat thyroid disorders, thyrotropin levels respectively above and under the reference range, and normal free thyroxine levels. For HRV, the participants underwent 10 min in supine position and the R-R intervals of the final 5 min were selected for analysis. We first used linear regression models to report crude data and then, multivariate adjustment for sociodemographic (age, sex, and race) and cardiovascular risk factors (hypertension, dyslipidemia, diabetes, smoking, body mass index, use of alcohol, and leisure physical activity) using the euthyroid group as reference. From 9270 subjects (median age, 50; interquartile range: 44-56), 8623 (93.0%) were classified as euthyroid, 136 (1.5%) as SCHyper, and 511 (5.5%) as SCHypo. Compared to euthyroid subjects, SCHyper participants presented significantly higher heart rate (68.8 vs 66.5 for euthyroidism, P=0.007) and shorter R-R intervals (871.4 vs 901.6, P=0.007). Although SCHyper was associated with lower standard deviation of NN interval (SDNN) (β: -0.070; 95% confidence interval (95%CI): -0.014 to -0.009) and low-frequency (LF) (β: -0.242, 95%CI: -0.426 to -0.058) compared to the euthyroid group, these differences lost significance after multivariate adjustment for confounders. No significant differences were found for HRV in SCHypo. No association was found between HRV and SCHyper or SCHypo compared to euthyroid subjects in this sample of apparently healthy subjects.

New challenge in subclinical thyroid disease:from guideline to practice / 中华内分泌代谢杂志

[Summary ] Accumulating evidence showed the associations between subclinical hyperthyroidism or subclinical hypothyroidism and adverse health outcomes. The related guidelines could be very helpful in making treatment decisions. However, even within the reference range, thyroid function is associated with adverse health outcomes, such as atrial fibrillation, coronary artery disease, osteoporosis, and dyslipidemia. Also, there is limitation to use TSH value as intervention threshold by the influence of age and other diseases. In this regard, a grading system is proposed to diagnose thyroid dysfunction, and risk stratification according to individual TSH values and comorbidities would be constructed to evaluate the utility of treatment.

Relationship between the subclinical thyroid dysfunction and the risk for fracture: A meta analysis / 中华内分泌代谢杂志

Objective To assess the association of subclinical thyroid dysfunction with fractures. Methods Medline, Embase, Pubmed, Cochrane Library, CBM, CNKI, Wan Fang, and VIP databases were systematically searched from January 1990 to August 2015 to identify prospective cohort studies which have studied the risk of fracture in patients with subclinical thyroid dysfunction. The relative risks ( RR) of cohort studies were pooled respectively, depending on the result of heterogeneity test among the individual studies search. The Stata (version 13. 0) software was used for meta-analysis. Results Nine prospective cohort studies including 292460 participants were identified as eligible for the meta-analysis. RR of subclinical hyperthyroidism for fracture was 1. 39(95%CI 1. 24-1. 55);for hip fracture, RR was 1. 24(95%CI 1. 10-1. 40);for nonspine fracture, RR was 1. 32 (95%CI 1. 09-1. 60). Different gender for subclinical hyperthyroid was associated with higher fracture rates:for females, RR was 1. 15(95%CI 1. 04-1. 27); for males, RR was 1. 31 (95% CI 1. 08-1. 59). The incidence of fracture in patients with subclinical hyperthyroidism was higher during the follow-up. For subclinical hypothyroidism, the RR was 1. 21(95% CI 1. 03-1. 42). Subgroup analysis indicated that there were significant differences between endogenous/exogenous subclinical hyperthyroidism and euthyroid, but no differences between endogenous/exogenous subclinical hypothyroidism and euthyroid were found. Conclusion Subclinical hyperthyroidism is associated with an increased risk of fracture in the population, especially hip fracture and nonspine fracture. During the course of subclinical hyperthyroidism, the incidences of fracture should be noticed both in females and males. However, there is no evidence which could prove a definite association between subclinical hypothyroidism and the risk of fracture.

The association between subclinical hyperthyroidism and early neurological deterioration in patients with acute cerebral infarction / 中华老年医学杂志

Objective To detect the association between subclinical hyperthyroidism and early neurological deterioration (END) in patients with acute cerebral infarction.Methods Totally 139 patients diagnosed with acute ischemic stroke were prospectively enrolled between March 2015 and September 2016.The early neurological deterioration was defined as 7-day in-hospital increase (vs.that at admission) in the NIHSS score of ≥2 points without any systemic cause.Multivariable Logistic regression analysis was conducted to evaluate the relationship between subclinical hyperthyroidism and END.Subclinical hyperthyroidism is defined as TSH ＜ 0.44 mU/L,with normal FT3 and FT4.Multivariable Logistic regression analysis was conducted to evaluate the relationship between subclinical hyperthyroidism and END.Results 42 (30.2％) patients with END among 139 with subclinical hyperthyroidism were observed.As compared with patients without END,patients with END showed older age[(71.2±5.7) years vs.(68.1±6.3) years,t=2.695,P=0.008],higher prevalence of subclinical hyperthyroidism (28.6％ vs.9.3％,x2 =8.506,P=0.006),and higher levels of C-reactive protein[5.6 (1.0,11.0) mg/L vs.2.5 (1.0,5.0) mg/L,Z=2.125,P=0.034],homocysteine[(15.3±5.8) mmol/L vs.(13.0±4.8) mmol/L,t=2.395,P=0.018]and fasting bloodglucose[(8.1 ± 2.2) mmol/L vs.(6.3 ± 2.6) mmol/L,t =4.108,P =0.001].Logistic regression analysis indicated that subclinical hyperthyroidism was associated with END after adjustment for potential confounders (OR =3.415,95 ％ CI:1.148-10.167,P =0.027).Conclusions Subclinical hyperthyroidism is a significant and independent predictor for END in patients with acute cerebral infarction.

The Relationship between Subclinical Thyroid Disease and Cardiovascular Disease Risk Score in Koreans

Subclinical hyperthyroidism and subclinical hypothyroidism are characterized by abnormal thyroid stimulating hormone (TSH) with normal free thyroxine. Subclinical thyroid diseases, to date, have received less attention compared with other thyroid diseases since they are asymptomatic. This study aimed to verify the association between subclinical thyroid diseases and cardiovascular diseases (CVDs) risk score in the Korean population. This was a population-based cohort study using data collected from 3,722 subjects (aged ≥ 30 years) during the 6th Korea National Health and Nutrition Examination Survey (KNHANES VI; 2013–2015). Gender-specific Framingham risk scores were calculated to identify the association between subclinical thyroid diseases and 10-year CVD risk score. Complex survey, with consideration of sampling weight, was analyzed using generalized linear models after stratification by gender. The TSH reference range was between 0.61 and 6.91 mIU/L in this study. TSH showed a positive association with the 10-year CVD risk score only in the female population (P = 0.001). There were significant differences in the least squares means of 10-year CVD risk score by the effect of subclinical hypothyroidism compared with euthyroidism (normal group) in females, after adjusting for body mass index, white blood cell, and urine iodine (P = 0.006 and Bonferroni corrected P = 0.012). In conclusion, subclinical hypothyroidism is associated with increased 10-year CVD risk score in the female Korean population aged 30 years or more. Therefore, we recommend to clinically checkup major CVD risk factors in female patients with subclinical hypothyroidism aged 30 years or more.

Does low serum TSH within the normal range have negative impact on physical exercise capacity and quality of life of healthy elderly people?

Objective Investigate the differences in cardiopulmonary (CP) capacity and Quality of Life (QOL) between healthy elderly (≥ 65 years) with different TSH levels (< 1.0 and ≥ 1.0 μIU/mL) both within the normal range. Also, evaluate the effects of TSH elevation on CP test and QOL, by administering methimazole to subjects with initial lower-normal TSH, in order to elevate it to superior-normal limit. Materials and methods Initially, a cross-sectional study was performed to compare CP capacity at peak exercise and QOL (using WHOQOL-OLD questionnaire) between healthy seniors (age ≥ 65 years) with TSH < 1.0 μIU/mL vs. TSH ≥1.0 μIU/mL. In the second phase, participants with TSH < 1.0 μIU/mL were included in a non-controlled-prospective-interventional study to investigate the effect of TSH elevation, using methimazole, on QOL and CP capacity at peak exercise. Results From 89 elderly evaluated, 75 had TSH ≥ 1 μIU/mL and 14 TSH < 1 μIU/mL. The two groups had similar basal clinical characteristics. No difference in WHOQOL-OLD scores was observed between groups and they did not differ in terms of CP function at peak exercise. QOL and CP variables were not correlated with TSH levels. Twelve of 14 participants with TSH < 1.0 μIU/mL entered in the prospective study. After one year, no significant differences in clinical caracteristics, QOL, and CP variables were detected in paired analysis before and after methimazole intervention. Conclusions We found no differences in CP capacity and QOL between health elderly with different TSH levels within normal range and no impact after one year of methimazole treatment. More prospective-controlled-randomized studies are necessary to confirm or not the possible harm effect in normal low TSH.

Prevalence of thyroid disorder in pregnancy and pregnancy outcome

Background: Thyroid disorders constitute one of the most common endocrine disorders seen in pregnancy. Maternal thyroid function changes during pregnancy and inadequate adaptation to these changes results in thyroid dysfunction. Aim: A prospective and comparative clinical study to know prevalence of thyroid disorder in pregnancy and pregnancy outcome was done. Materials and methods: This study was carried out in pregnant women during 1st trimester who attended antenatal clinic of maternity hospital to know the prevalence of thyroid disorders in pregnant women living in and around and also to know the outcome of pregnancy in women suffering from thyroid disorders. Results: In this study, prevalence of thyroid disorder was 11.6% with 95% CI of 9.64 to 13.54 which was high when compared to other regions in India and in other parts of Asia. Subclinical hypothyroidism and Overt hypothyroidism was 6.4% and 2.8% respectively. Subclinical and Overt hyperthyroidism was 1.8% and 0.6% respectively. Subclinical hypothyroidism was more prevalent and hidden, leading to the poor obstetrical outcome and fetal complications. Rate of miscarriage was high in overt hyperthyroid patients. Conclusion: Due to the immense impact that the maternal thyroid disorder has on maternal and fetal outcome, prompt identification of thyroid disorders and timely initiation of treatment is essential. Thus, universal screening of pregnant women for thyroid disorder should be considered especially in a country like India where there is a high prevalence of undiagnosed thyroid disorder.

Prevalence and Risk Factors of Subclinical Thyroid Disease

Subclinical thyroid disease is defined biochemically by an abnormal thyrotropin (TSH) level and normal serum-free thyroxine level. The prevalence of this condition varies according to the reference range for TSH and geographic or demographic factors. Recently, several studies, including our community-based cohort studies, have reported on the incidence of subclinical thyroid disease in Korea. Using these studies, we reviewed the prevalence and risk factors of subclinical thyroid disease, focusing on subclinical hypothyroidism.

Subclinical Thyroid Dysfunction in the Elderly

Subclinical thyroid dysfunction, including both subclinical hyperthyroidism and subclinical hypothyroidism is biochemically defined as an abnormal thyroid-stimulating hormone (TSH) level and thyroid hormone level within its reference range. The prevalence of this condition varies according to the reference range for TSH and geographic or demographic factors, but is common in the elderly and in women. Subclinical thyroid dysfunction has various causes. Thus, careful clinical assessment is needed. Subclinical thyroid dysfunction can be likely to progress to overt thyroid disease and be associated with various health outcomes. However, to date, supporting data are lacking and levels of evidence for the associations are different. Although the management of subclinical thyroid dysfunction is controversial, recommendations are based on the degree to which TSH levels have deviated from normal, age, symptoms, and underlying comorbidities. Further studies are needed to inform how to best care for the elderly with subclinical thyroid dysfunction.

Longevity and thyroid dysfunctions in the elderly / 中华内分泌代谢杂志

This article summarizes the current literature about serum test parameters of thyroid function during aging and thyroid dysfunction in the elderly.The aim is to highlight the importance of the individualized strategy and employing additional caution before assigning diagnoses of hypothyroidism or hyperthyroidism to elderly patients and initiation of treatment modalities.In the last few years,the emergence of age-specific reference ranges for thyroid-stimulating hormone (TSH) has added to the complexity of diagnosis of thyroid dysfunction in this age group,especially in thesubclinical category.Application of age-specific TSH reference ranges may avoid misclassification of elderly subjects without thyroid disease.Overt hypothyroidism and hyperthyroidism require immediate treatment.Treatment of subclinical hyperthyroidism may be considered in the part of elderly patients,while follow-up care and monitoring must be provided for the other part of older subjeets.Careful waiting may be an appropriate approach for older patients with subclinical hypothyroidism with TSH＜ 10 mU/L.The senile elderly,especially extreme longevity people with TSH＜10 mU/L are generally not treated with thyroid hormone replacement therapy.

Radioiodine therapy in elderly patients with subclinical hyperthyroidism due to non-voluminous nodular goiter and its effect on bone metabolism / Terapia com radioiodo em pacientes idosos com hipertireoidismo subclínico por bócio nodular não volumoso e efeito sobre o metabolismo ósseo

OBJECTIVE: To evaluate 131I therapy in elderly patients with subclinical hyperthyroidism (SCH) due to nodular disease and who did not receive antithyroid drugs (ATDs), and the effect of the treatment on bone metabolism. SUBJECTS AND METHODS: Thirty-six patients with TSH ≤ 0.1 mIU/L and non-voluminous goiter (< 60 cm³) were studied. Bone mineral density (BMD) was assessed in 17 women with osteopenia. RESULTS: Mean 24-h 131I uptake was 17.5%. Symptoms of thyrotoxicosis were reported by two (5.5%) patients in the first week after therapy. One year after radioiodine treatment, SCH was resolved in 30 (83.3%) patients, and hypothyroidism was detected in one (2.7%). In the patients in whom TSH returned to normal, femoral and lumbar spine BMD increased by 1.9% and 1.6%, respectively, in average. CONCLUSIONS: In elderly patients with SCH and non-voluminous goiter, radioiodine not preceded by ATDs is a safe and effective therapeutic alternative. Resolution of SCH has beneficial effects on BMD in postmenopausal women with osteopenia.

OBJETIVO: Avaliar a terapia com 131I em idosos com hipertireoidismo subclínico (HSC) por doença nodular que não receberam drogas antitireoidianas (DATs) e o efeito no metabolismo ósseo. SUJEITOS E MÉTODOS: Trinta e seis pacientes com TSH ≤ 0,1 mUI/L e bócio não volumoso (< 60 cm³) foram estudados. Dezessete mulheres com osteopenia foram submetidas à avaliação da densidade mineral óssea (DMO). RESULTADOS: Captação média de 131I em 24 h foi 17,5%. Sintomas de tireotoxicose foram reportados por dois pacientes (5,5%) na primeira semana após a terapia. Um ano após o radioiodo, HSC foi resolvido em 30 pacientes (83,3%) e hipotireoidismo ocorreu em 1 (2,7%). Nas pacientes que normalizaram o TSH, DMO em fêmur e coluna lombar incrementou em média 1,9% e 1,6%, respectivamente. CONCLUSÕES: Em idosos com HSC e bócio não volumoso, radioiodo, não precedido de DATs, é uma alternativa terapêutica segura e eficaz. Resolução do HSC tem benefício na DMO em mulheres menopausadas com osteopenia.

Dietary iodine intake and the association with subclinical thyroid dysfunction in male workers

The prevalence rate of thyroid dysfunction (hypothyroidism and hyperthyroidism) has increased within the Korean population and seems to be affected by iodine dietary habits. Some studies reported that the prevalence of thyroid dysfunction increase both in the area of iodine deficiency and excess. In this study, we tried to discover the difference in iodine intake, anthropometric measurements, and blood parameters between male subjects with or without subclinical thyroid dysfunction. A total of 5,249 subjects (Euthyroid: 4706, SubHypo: 454, SubHyper: 89) were used in this study. There were no significant differences in BMI, body fat, visceral fat, waist circumference, SBP, DBP, total cholesterol, HDL-cholesterol, LDL-cholesterol, TG, fasting serum glucose, HbA1c, alcohol intake, however significant differences were noticed in both age and smoking status. Through a food frequency questionnaire (FFQ), iodine intake per day was estimated. The average iodine intake was similar (SubHypo 392.9 +/- 279.0 microg, Euthyroid 376.5 +/- 281.7 microg, SubHyper 357.3 +/- 253.8 microg) among groups. The main source of iodine intake was eggs (52.8%, 54.2%, 52.4%) followed by milk (16.3%, 15.8%, 17.8%), then sea mustard & sea tangle (12.4%, 11.9%, 11.6%). The prevalence of subclinical hypothyroidism and subclinical hyperthyroidism was higher in subjects whose intake was higher than the recommended nutrient intake (RNI). These results suggest that the excess consumption of iodine intake may act as one of the risk factors regarding thyroid dysfunction in Korea. Therefore, an adequate amount of iodine intake is necessary in order to prevent subclinical thyroid dysfunction and clinical thyroid dysfunction.

Bone and heart abnormalities of subclinical hyperthyroidism in women below the age of 65 years / Anormalidades ósseas e cardíacas do hipertireoidismo subclínico em mulheres com menos de 65 anos

The objective of the present study was to evaluate bone and cardiac abnormalities and symptoms and signs of thyroid hormone excess in women with subclinical hyperthyroidism (SCH) aged < 65 years. Forty-eight women with SCH were evaluated. The control group consisted of 48 euthyroid volunteers. The mean symptom rating scale score was significantly higher in patients. Cardiac involvement, both morphological and affecting systolic and diastolic functions, was also observed in patients. Women with SCH showed a significant increase in serum markers of bone formation and resorption. In addition, bone mineral density (BMD) was lower in the femoral neck but not in the lumbar spine in patients before menopause, whereas a lower BMD was observed at both sites in postmenopausal patients. SCH is not completely asymptomatic in women aged < 65 years, and is associated with heart abnormalities and with increased bone turnover and reduced BMD even before menopause.

O objetivo deste estudo foi avaliar as anormalidades ósseas e cardíacas, sintomas e sinais de excesso de hormônio tireoidiano em mulheres com hipertireoidismo subclínico (HSC) e menos de 65 anos de idade. Quarenta e oito mulheres com HSC foram avaliadas. O grupo-controle consistiu de 48 voluntárias eutireoidianas. A média do escore de sintomas foi significativamente maior em pacientes que em controles. Comprometimento cardíaco, morfológico e afetando as funções sistólica e diastólica, também foi observado. Mulheres com HSC apresentaram significativo aumento dos marcadores séricos de formação e reabsorção óssea. A densidade mineral óssea (DMO) foi menor no colo de fêmur, mas não em coluna lombar em mulheres antes da menopausa; enquanto e em ambos os sítios nas mulheres pós-menopausadas. HSC não é inteiramente assintomático em mulheres com menos de 65 anos, está associado a anormalidades cardíacas morfológicas e funcionais, incremento da remodelação óssea, e menor DMO, mesmo antes da menopausa.

Frecuencia de hiper e hipotiroidismo subclínicos en pacientes derivados al Instituto de Investigaciones en Ciencias de la Salud / Frequency of subclinical hyper and hypothyroidism in patients referred to the Instituto de Investigaciones en Ciencias de la Salud

El hiper e hipotiroidismo subclínicos, son patologías que cursan con una sintomatología inespecífica, lo que dificulta muchas veces su diagnóstico precoz. El objetivo de este estudio fue estimar la frecuencia de estas disfunciones a partir de la alteración laboratorial de los valores de la hormona estimulante de la tiroides, la tirotropina. Es un estudio observacional retrospectivo de 561 fichas previamente codificadas de pacientes que concurrieron con pedido médico para un chequeo de control de hormonas tiroideas, al departamento de Endocrinología laboratorial del IICS durante un periodo de tres años (2004-2006). Otras variables consideradas fueron sexo, edad y molestias físicas que refirieron los pacientes en el momento de la toma de la muestra. La frecuencia de hipotiroidismo subclínico fue de 63,1% (354 pacientes) y de hipertiroidismo subclínico fue de 36,9% (207 pacientes). Se encontró que ambas disfunciones la frecuencia es mayor en mujeres 93,8% (523 pacientes), en el intervalo de edad comprendido entre 31 a 50 años.En base a que la sintomatología es muy inespecífica, y son detectadas en forma precoz mediante la determinación laboratorial de la hormona tirotropina, sería de utilidad, la inclusión de un control sistemático cada cinco años, en la población en general a partir de los 35 años de edad, especialmente en mujeres, tal como lo recomienda la Asociación Americana de Tiroides (ATA).

The subclinical hyper and hypothyroidism are pathologies with a non-specific symptomatology, which often hampers their early diagnosis. The objective of this study was to estimate the frequency of these dysfunctions from the laboratory alteration of the values of the thyroid stimulating hormone, thyrotropin. It is a retrospective observational study of 561 pre-coded records of patients who attended the department of endocrinology of the IICS for a checkup control of thyroid hormones during three years (2004-2006). Other variables considered were gender, age and physical discomforts that patients referred at the time of sample collection. The frequency of subclinical hypothyroidism was 63.1% (354 patients) and subclinical hyperthyroidism was 36.9% (207 patients). It was found the frequency of both malfunctions is higher in women 93.8% (523 patients), in the age range of 31 to 50 years. As the symptoms of these malfunctions are very unspecific and they may be early detected by the laboratory determination of the thyrotropin, it would be useful the inclusion of a systematic control every five years, in the general population from 35 years of age, especially women, as recommended by the American Thyroid Association (ATA).

Induced Life-Threatening Electrolyte Imbalance in Sub-clinical Hyperthyroidism -A case report-

Thyrotoxic periodic paralysis (TPP) is rare in white Caucasian but a few in Asian. A 36-year-old man presented with suddenly developed paraparesis was brought by ambulance. He got some medications and injection for the upper respiratory infection in the morning of admission day. On admission he revealed bilateral proximal muscle weakness without pain. He didn't have any specific medical history of himself and his family. The laboratory results on admission revealed severe hypokalemia (2.1 mM/l). Potassium replacement was immediately started and his symptom was gone. We found TSH was extremely decreased (<0.005 microIU/ml) but T3 and T4 were within normal level. We guess TPP was induced by some drugs to the patient with sub-clinical hyperthyroidism. Hyperthyroidism is not always clinically apparent and then may be easily missed. However just a single medication or injection that is usually prescribed can induce critical progressive hypokalemia.

Effect of thyroid function on blood pressure / 中国实用内科杂志

Overt hyperthyroidism and hypothyroidism can induce hypertension.Recent studies found that mild thyroid dysfunction including subclinical thyroid diseases and increased TSH during normal reference range also had effect on blood pressure which had not been agreed with others.The mechanism is complex and not yet very clear.The basic treatment for the patients with thyroid diseases and hypertension is to treat thyroid diseases.Beta-receptor blocking agents and diuretics are preferable drugs for hyperthyroidism.