Reversible cognitive, motor, and driving impairments in severe hypothyroidism

Neurological soft signs and thyroid hormones in schizophrenia spectrum disorders

BACKGROUND

Neurological soft signs (NSS) are minor sensory and motor deviations linked to neurodevelopmental disorders and schizophrenia spectrum disorders (SSD). Thyroid hormones (TH) are essential for neurodevelopment and are suggested to be altered in SSD. Yet, the relationship between NSS and TH is unclear.

OBJECTIVES

We evaluated the relationship between NSS and TH in individuals with SSD.

METHODS

We examined a total of 72 individuals with SSD. We assessed NSS using the Neurological Evaluation Scale (NES) and clinical symptoms using the Positive and Negative Syndrome Scale (PANSS). We collected fasting blood samples to measure serum levels of thyroid-stimulating hormone (TSH), free thyroxine (fT4), and free triiodothyronine (fT3). We used the t-test to compare differences between sex and the Pearson correlation to test for correlations between NSS, TH and psychopathology separately for males and females.

RESULTS

We observed a negative correlation between fT4 and NES total score (r = -0.374, p = .032), and NES subdomain "sensory integration" (r = -0.372, p = .033). The correlation between fT4 and "sensory integration" remained largely unchanged when controlling for age, DOI, and antipsychotic dose in OLZ equivalents by performing partial correlation analyses (r = -0.424, p = .049). Serum fT3 and TSH levels exhibited no significant correlation with NES scores but the PANSS negative symptoms score was negatively associated with fT3 (r = -0.472, p < .001).

CONCLUSIONS

Lower fT4 levels were associated with NSS severity and specific NSS subdomains only in male individuals. In the overall sample, we detected a significant negative correlation between fT3 and negative symptoms. Future studies should examine a larger sample of drug-naïve individuals with SSDs, followed-up longitudinally in time to infer causality.

Association between thyroid hormones and cognitive functioning in euthyroid elderly adults: a cross-sectional preliminary study from the NHANES 2011-2012 survey

Objective

Changes in serum thyroid hormone levels may affect cognitive functioning in euthyroid individuals. This study used representative data from the National Health and Nutrition Examination Survey (NHANES) to comprehensively examine the association of thyroid hormones with different tests of cognitive functioning among US elderly people aged ≥60 years.

Methods

This study was a cross-sectional preliminary study with a total of 734 participants from the NHANES 2011-2012 survey. Thyroid function was measured using competitive binding immune-enzymatic assays, while cognitive functioning was measured using a series of assessments, including the Consortium to Establish a Registry for Alzheimer's Disease-Word Learning (CERAD W-L), Animal Fluency Test, and Digit Symbol Substitution Test (DSST). Weighted multiple linear regression models and binary logistic regression analyses were used to examine the association between thyroid hormone levels and cognitive functioning. All statistical analyses were performed using SPSS version 20.0, and R software.

Results

Weighted multivariable linear regression showed that FT3 was negatively associated with the Animal Fluency Test and DSST (β=-0.113, 95% CI: -3.279, -0.803, P=0.001; β=-0.062, 95% CI: -6.565, -0.470, P=0.024, respectively) after adjustment for potential covariates. subgroup analysis stratified by sex revealed a negative association between FT3 levels and the Animal Fluency Test in men (β=-0.163, 95% CI: -4.643, -1.153, P=0.001). For female participants, FT3 was negatively associated with not only the Animal Fluency Test but also DSST (β=-0.099, 95% CI: -3.543, -0.093, P=0.039; β=-0.093, 95% CI: -10.288, -1.326, P=0.011). Binary logistic regression showed that the significantly increased adjusted odds ratios (aORs) (95% CI) between the risk of impaired cognitive functioning and FT3 across Q3 and Q4 compared with Q1 were 2.025 (1.092, 3.753) and 2.365 (1.261, 4.433), respectively, for DSST in overall participants. Furthermore, there were significant differences between participants with and without impaired cognitive functioning for serum FT3 levels in overall participants based on DSST score (P=0.020).

Conclusions

There was a significant inverse relationship between FT3 levels within the normal range and cognitive functioning after adjusting for potential covariates. Future longitudinal cohort studies should be conducted to determine the causal relationship between thyroid hormone levels and cognitive functioning.

Oldie but Goldie: The Fundamental Role of Radioiodine in the Management of Thyroid Cancer

Background/Objectives: The management of differentiated thyroid cancer (DTC) patients has undergone a major paradigm shift in past years, especially regarding the role of a careful postoperative disease assessment both in deciding for or against the use of iodine-131 therapy (i.e., patients' selection) and in selecting the correct goal of the treatment: ablative, adjuvant or therapeutic. Furthermore, diagnostic and risk-oriented uses of iodine isotopes (i.e., 123/124/131I) should always be considered during both postoperative assessment and follow-up of DTC patients to improve early staging and response assessment to initial treatments, respectively. The present review summarizes current (and real-life-related) evidence and the emerging perspectives on the therapeutic, diagnostic, and theragnostic use of radioiodine isotopes. Methods: A review of the pertinent literature was performed in PubMed, Web of Science, and Scopus without language restrictions or time limits and using one or more fitting search criteria and terms. Results: According to the literature evidence and real-life clinical practice, a risk-oriented postoperative iodine-131 therapy remains pivotal for most DTC patients and improves early disease staging through post-therapy functional imaging (i.e., theragnostic aim). Accordingly, the goal of iodine-131 therapy, the optimal strategy (empiric vs. dosimetric approach), the appropriate stimulation method [i.e., levothyroxine (L-T4) withdrawal vs. recombinant human thyrotropin (rhTSH) administration] and, finally, the suggested radioiodine activity to deliver for iodine-131 therapy (RIT) should be personalized, especially in metastatic DTC patients. Conclusions: The evidence related to the diagnostic and theragnostic use of iodine isotopes leads to a significant improvement in the postoperative risk stratification and staging of DTC patients in addition to a more accurate assessment of the response to initial treatments. In conclusion, radioiodine is really an oldie but goldie radiotracer. It has both a current fundamental role and a future perspective for the more careful management of DTC patients.

Short-Term Postoperative Depression and Anxiety in Patients with Differentiated Thyroid Carcinoma: Assessment of Potential Oncologic-Psycho Relevance

Objective: To understand whether TSH suppressive therapy affect short-term postoperative cancer-related depression and anxiety among DTC patients. To evaluate short-term postoperative psychological problems and its relationship with baseline parameters, fatigue, sleep quality, illness perception, and patients' quality of life. Study Design and Methods: This was a prospective, observational, single center study. This study involved 831 TC patients who consecutively admitted to the inpatient department of hospital between 1st June 2020 and 31th February 2021. Results: Mean scores of the self-rated anxiety scale (SAS) (49.04 vs. 40.69) and self-rated depression scale (SDS) (44.61 vs. 39.86), as well as the incidence of anxiety (41.5% vs. 22.1%) and depression (22.5% vs. 2.4%) significantly decreased 3 months after surgery. For personal and clinical characteristics, low educational background (SAS, β = 1.392; SDS, β = 1.622; and p < 0.05), without children (SAS, β = 4.068; SDS, β = 1.873, and p < 0.01), FNAC (SAS, β = -0.981; SDS, β = -2.583; and p < 0.05), and multifocal tumor (SAS, β = -1.287; SDS, β = -2.681; and p < 0.05) were the main effects for both short-term postoperative anxiety and depression. Multiple linear regression analysis identified the serum TSH level as a significant variable associated with worse SAS (Beta = -0.695 and p=0.043) and SDS (Beta = -3.133 and p < 0.001) scores 3 months after surgery. FT4 was independently associated with SAS scores (Beta = -0.202 and p < 0.001). Patients with middle ATA risk had a significantly higher level of SDS scores (p=0.033). Conclusion: We confirmed that cancer-related anxiety and depression among DTC patients significantly alleviated 3 months after surgery. TSH suppression therapy has profound effects on cancer-related anxiety and depression, and the degree of anxiety and depression significantly deteriorated with the decrease of TSH level.

Chronic pain predicts a worse response to depression treatment, regardless of thyroid function or psychotropics prescribed

BACKGROUND

Chronic pain (CP) and thyroid hormones' (TH) abnormalities are associated with depression, but the impact of pain and TH fluctuation on the response to depression treatment is uncertain.

METHODS

Eighty-eight patients with major depression were evaluated before and after 6 months of specific treatment, through scales of symptoms' severity (HAM-D-17), psychomotor disturbance (CORE), and quality of life (WHOQOL-Bref). We reviewed psychiatric medications and measured TSH, T3 and T4. We used Generalized Estimating Equations to assess the interaction effect between CP and treatment time on depression severity and TH levels, and Bonferroni to compare means.

RESULTS

47.7 % of the patients had CP. Patients with and without CP did not differ at baseline. At follow-up, those with CP experienced a more modest decrease in symptoms' severity and no improvement in any domain of psychomotor disturbance, contrasting with a decrease of over 40 % from the baseline values of CORE in patients without CP (non-CP). Initial and final scores were respectively: HAM-D CP 24.06 and 19.3, Δ = -4.75; HAM-D non-CP 22.92 and 14.7, Δ = -8.21; CORE CP 5.36 and 5.24, Δ = -0.12; CORE non-CP 5.8 and 3.22, Δ = -2.57. There was no interaction with TH or life quality. Model adjustments for psychotropic drugs received and sensitivity analysis excluding somatic symptoms from severity scales did not impact the results.

LIMITATIONS

Findings may not replicate in mildly depressed patients from primary care. Pain scales were not applied.

CONCLUSIONS

Individuals with chronic pain showed a suboptimal response to depression treatment, regardless of the medications used or TH levels.

Thyroid Hormone Withdrawal versus Recombinant Human TSH as Preparation for I-131 Therapy in Patients with Metastatic Thyroid Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Differentiated thyroid carcinoma (DTC) is characterized by an excellent prognosis with a 10-year survival rate > 90%. However, when DTC develops in a metastatic form, it has been shown to significantly impact patient survival and quality of life. Although I-131 has been shown to be an effective therapy in patients with metastatic DTC, whether its efficacy after recombinant human TSH (rhTSH) is comparable to endogenous TSH stimulation by thyroid hormone deprivation (THW) is still debated. Our present study was prompted to compare clinical results obtained in metastatic DTC by I-131 administered after rhTSH and THW stimulation protocols, respectively.

METHODS

A systematic search on PubMed, Web of Science, and Scopus was performed from January to February 2023. Pooled risk ratios with 95% CI were determined for evaluating the initial response after to I-131 therapy after preparation with rhTSH or THW and the disease progression. To track the accumulation of evidence and reduce type I errors because of small data, a cumulative meta-analysis was performed. A sensitivity analysis was also performed to examine the impact of individual studies on overall prevalence results.

RESULTS

Ten studies were included with a total of 1929 patients pre-treated with rhTSH (n = 953) and THW (n = 976), respectively. The cumulative data of our systematic review and meta-analysis showed an increase in the risk ratio over the years without any change in favour of a pre-treatment or the other on the effectiveness of I-131 therapy of metastatic DTC.

CONCLUSIONS

Our data suggest that pretreatment with rhTSH or THW has no significant impact on the effectiveness of I-131 therapy for metastatic DTC. This implies that concerns about the use of one or the other pretreatment should be deferred to clinical evaluations made considering patient characteristics and reduction in side effects.

Cognitive decline in mid-life: Changes in memory and cognition related to hypothyroidism

This study assessed specific cognitive impairments within a primarily female, hypothyroid population, while controlling for factors that commonly contribute to cognitive decline. Participants (N = 739) included 461 individuals with hypothyroidism. This study involved an online survey assessing several aspects of memory and cognition. Those with hypothyroidism generally scored worse on self-assessments of memory, higher perceived stress, high rates of depression and anxiety, greater fatigue, poorer concentration, and less motivation. A Receiver Operating Characteristic curve indicated that the cognitive questionnaires are successful at classifying hypothyroidism and a mediation analysis showed fatigue is a mediating symptom of these cognitive outcomes.

Exploration of RCBF and Metabolic Changes in the Brain Functional Areas of Patients with Hypothyroidism by ASL and MRS Techniques

Objective

To study the regional cerebral blood flow (rCBF) in important brain functional areas and the metabolic levels of these brain functional areas in patients with primary hypothyroidism by using arterial spin labeling (ASL) and magnetic resonance spectroscopy (MRS) techniques to explain the possible causes of brain dysfunction in patients with primary hypothyroidism.

Methods

Twenty-five patients with primary hypothyroidism (newly diagnosed and not treated) who were treated in the endocrinology department of our hospital were selected as the research group, and 25 healthy patients with normal thyroid function who came to our hospital during the same period with matched gender and age were selected as the control group. ASL and MRS techniques were used to detect and calculate regional cerebral blood flow (rCBF) in the frontal lobe, hippocampus, and posterior cingulate gyrus, as well as N-acetylaspartate/creatine (NAA/Cr), choline/creatine (Cho) in the brain/Cr, and inositol/creatine (mI/Cr) ratio. The correlations between metabolite ratios measured by rCBF, MRS, and serum TSH, FT3, and FT4 levels were analyzed.

Results

Compared with the control group, the rCBF in the frontal lobe, hippocampus, and posterior cingulate gyrus of the dominant hemisphere of the hypothyroid patients in the study group decreased significantly (P < 0.05). The comparison of metabolite ratios showed that compared with the control group, the NAA/Cr ratio of the frontal lobe and posterior cingulate gyrus of the study group was significantly decreased, and the Cho/Cr ratio of the posterior cingulate gyrus of the study group was significantly increased. The MI/Cr ratio of the hippocampus was significantly decreased (all P values < 0.05). Correlation analysis showed that rCBF and NAA/Cr in posterior cingulate gyrus were significantly negatively correlated with serum TSH levels (P < 0.05).

Conclusion

The changes of rCBF and metabolite ratios in the frontal lobe, hippocampus, and posterior cingulate gyrus of patients with primary hypothyroidism can be detected using ASL and MRS techniques. The changes of rCBF and metabolite ratio and their negative correlation with serum TSH level are helpful to explain the causes of brain dysfunction in patients with primary hypothyroidism.

Hypothyroidism and Diabetes-Related Dementia: Focused on Neuronal Dysfunction, Insulin Resistance, and Dyslipidemia

The incidence of dementia is steadily increasing worldwide. The risk factors for dementia are diverse, and include genetic background, environmental factors, sex differences, and vascular abnormalities. Among the subtypes of dementia, diabetes-related dementia is emerging as a complex type of dementia related to metabolic imbalance, due to the increase in the number of patients with metabolic syndrome and dementia worldwide. Thyroid hormones are considered metabolic regulatory hormones and affect various diseases, such as liver failure, obesity, and dementia. Thyroid dysregulation affects various cellular mechanisms and is linked to multiple disease pathologies. In particular, hypothyroidism is considered a critical cause for various neurological problems-such as metabolic disease, depressive symptoms, and dementia-in the central nervous system. Recent studies have demonstrated the relationship between hypothyroidism and brain insulin resistance and dyslipidemia, leading to diabetes-related dementia. Therefore, we reviewed the relationship between hypothyroidism and diabetes-related dementia, with a focus on major features of diabetes-related dementia such as insulin resistance, neuronal dysfunction, and dyslipidemia.

Association of lipoproteins and thyroid hormones with cognitive dysfunction in patients with systemic lupus erythematosus

Background

Neuropsychiatric manifestations occur in up to 75% of adult systemic lupus erythematosus (SLE) patients and are one of the major causes of death in SLE patients. Cognitive dysfunction is a typical clinical feature of neuropsychiatric SLE (NPSLE), which seriously affects the quality of life of patients. Dyslipidaemia and thyroid symptoms, which are prevalent in SLE patients, have both been related to neuropsychiatric disturbances, including significant psychiatric and cognitive disturbances. This study aimed to investigate whether cognitive dysfunction in patients with SLE was related to the expression of serum thyroid hormone and lipoprotein levels.

Methods

A total of 121 patients with SLE and 65 healthy controls (HCs) at Nanjing Drum Tower Hospital completed a cognitive function test, and 81 SLE patients were divided into a high-cognition (n = 33) group and a low-cognition group (n = 48). The clinical and laboratory characteristics of the patients were compared; moreover, correlations between serum HDL-C, LDL-C, F-T3 and F-T4 levels and cognitive function were analysed. Serum levels of APOE, APOA1, IGF-1, and IGFBP7 in 81 patients were detected by ELISA, and the correlation between these four proteins and cognition was analysed separately.

Results

The patients with SLE with abnormal cognitive function were less educated than the HCs. For low-cognition patients, the levels of albumin, F-T3 (P <  0.05) and F-T4 decreased, while D-dimer, anti-dsDNA antibody, and IgM levels increased. Serum F-T3 and F-T4 levels positively correlated with cognition. Furthermore, serum protein levels of APOE and APOA1 showed no difference between the high- and low-cognition groups. However, the serum APOE levels were negatively correlated with line orientation scores, and APOA1 levels were positively correlated with coding scores.

Conclusions

Serum F-T3 and F-T4 levels were both positively correlated with four indexes of cognition (language was the exception), while serum APOE levels were negatively correlated with line orientation scores, APOA1 levels were positively correlated with coding scores, and IGFBP7 levels were negatively correlated with figure copy scores. These results demonstrated that F-T3 and F-T4 might be clinical biomarkers of cognitive dysfunction in SLE.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41927-021-00190-7.

What Is the Quality of Life in Patients Treated with Levothyroxine for Hypothyroidism and How Are We Measuring It? A Critical, Narrative Review

Thyroid hormone replacement therapy (THRT, generally using oral levothyroxine (LT4)) is a safe, effective means of treating hypothyroidism. However, a proportion of LT4-treated patients with biochemically normal thyroid function tests complain of persistent symptoms that impact their health-related quality of life (QoL). The objectives of this critical, narrative review of the literature were to identify studies of QoL in LT4-treated patients with hypothyroidism, examine the instruments used to measure QoL, determine whether normal QoL is restored by THRT, and identify factors associated with QoL. The PubMed database was searched from 1 January 2000 to 31 December 2020. A total of 809 publications were screened, 129 full-text articles were retrieved, and 58 were analyzed. The studies of overt hypothyroidism evidenced an improvement in psychological and emotional well-being after three to six months of THRT with LT4, although contrasting results were found for patients with subclinical hypothyroidism. Combination treatment with LT4 and liothyronine was not generally associated with better QoL. In hypothyroidism, QoL appears to be influenced by a number of physiological, behavioral, cognitive and/or lifestyle factors that are not strictly related to thyroid hormone levels.

The relation between thyroid dysregulation and impaired cognition/behaviour: An integrative review

Despite decades of research on the relation between thyroid diseases and cognition, the nature of this relationship remains elusive. An increasing prevalence of cognitive impairment and thyroid dysfunction has been consistently observed with ageing. Also, there appears to be an association between thyroid disorders and cognitive decline. Given the increasing global burden of dementia, elucidating the relationship between thyroid disorders as a potentially modifiable risk factor of cognitive impairment was the main goal of this review. We summarise the current literature examining the relationship between thyroid hormonal dysregulation and cognition or behaviour. We present the available imaging and pathological findings related to structural and functional brain changes related to thyroid hormonal dysregulation. We also propose potential mechanisms of interaction between thyroid hormones, autoantibodies and cognition/behaviour. Effects of gender, ethnicity and environmental factors are also briefly discussed. This review highlights the need for long-term prospective studies to capture the course of brain functional changes associated with the incidence and progression of thyroid dysregulations along with the confounding effects of non-modifiable risk factors such as gender and ethnicity. Moreover, double-blind controlled clinical trials are necessary to devise appropriate treatment plans to prevent cognitive consequences of over or undertreatment of thyroid disorders.

Cognitive Impairment and Associated Factors Among Adult Hypothyroid Patients in Referral Hospitals, Amhara Region, Ethiopia: Multicenter Cross-Sectional Study

BACKGROUND

Cognitive impairment is a common complication of hypothyroidism that affects the patient's quality of life in different aspects. In Ethiopia, though the prevalence of hypothyroidism is high the magnitude of cognitive impairment among these patients is not known. Therefore, the current study is aimed at determining the prevalence of cognitive impairment and associated factors among adult hypothyroid patients.

METHODS

An institution-based cross-sectional study was employed from February 24 to May 22, 2020, to assess the prevalence of cognitive impairment and associated factors among adult hypothyroid patients. Data was collected by a pretested interviewer-administered structured questionnaire and standardized Mini-mental state examination (SMMSE) tool. A cluster sampling technique was used. Data was entered into Epidata version 4.6 and exported into a statistical package for social science (SPSS) version 25 for further analysis. Both bivariable and multivariable logistic regression analyses were done. A 95% confidence interval and P-value <0.05 were used to declare statistical significance.

RESULTS

A total of 216 adult hypothyroid patients were included with a response rate of 98.6%. The mean age was 42.5 (± 11) years. The prevalence of cognitive impairment was 27.3% (95% CI (21.7, 33.8)) and it was significantly associated with increased age (AOR = 1.23, 95% CI (1.11, 1.34)), increased duration of illness (AOR = 1.48, 95% CI (1.14, 1.90)) and high thyroid-stimulating hormone (TSH) level (AOR = 1.3, 95% CI (1.1, 1.6)).

CONCLUSION

The prevalence of cognitive impairment among hypothyroid patients was high. Increased age, increased duration of illness and high TSH levels were significantly associated with cognitive impairment. Hence, early screening of cognitive impairment among hypothyroid patients with increased age, increased duration of illness and high TSH level should be given due emphasis to increase patients quality of life.

Allan-Herndon-Dudley-Syndrome: Considerations about the Brain Phenotype with Implications for Treatment Strategies

Despite its first description more than 75 years ago, effective treatment for "Allan-Herndon-Dudley-Syndrome (AHDS)", an X-linked thyroid hormone transporter defect, is unavailable. Mutations in the SLC16A2 gene have been discovered to be causative for AHDS in 2004, but a comprehensive understanding of the function of the encoded protein, monocarboxylate transporter 8 (MCT8), is incomplete. Patients with AHDS suffer from neurodevelopmental delay, as well as extrapyramidal (dystonia, chorea, athetosis), pyramidal (spasticity), and cerebellar symptoms (ataxia). This suggests an affection of the pyramidal tracts, basal ganglia, and cerebellum, most likely already during fetal brain development. The function of other brain areas relevant for mood, behavior, and vigilance seems to be intact. An optimal treatment strategy should thus aim to deliver T3 to these relevant structures at the correct time points during development. A potential therapeutic strategy meeting these needs might be the delivery of T3 via a "Trojan horse mechanism" by which T3 is delivered into target cells by a thyroid hormone transporter independent T3 internalization.

Altered attention networks in patients with thyroid dysfunction: A neuropsychological study

Patients with thyroid dysfunction (31 hypothyroid, 32 subclinical hypothyroidism, 34 hyperthyroid, and 30 subclinical hyperthyroidism) and 37 euthyroid control subjects were recruited and performed the attention network test (ANT), which can simultaneously examine the alertness, orientation and execution control of the participants. Patients with hypothyroidism had abnormalities in the alerting network, and those with hyperthyroidism had impairments of the alerting and executive control networks. No attention networks deficit existed in patients with subclinical hyperthyroidism and subclinical hypothyroidism. The anxiety and depression scores of patients with thyroid dysfunction were significantly higher than those of the healthy control group. Covariance analysis demonstrated that interactions between group and Hamilton Anxiety Scale scores, group and HAMD score were not significant, but there was a significant main effect for group when analyzing the difference in values of the alerting network between groups. Further, the efficiency of the executive control network was negatively correlated with the T4 level in the hypothyroidism group, and positively correlated with the T4 level in the hyperthyroidism group. T4 or T3 level and efficiencies of the executive control network had a significant quadratic U-shaped relationship in all participants. In summary, the patients with four kinds of thyroid dysfunction exhibited different characteristics of ANT performance. Patients with thyroid dysfunction had various degrees of anxiety and depression disorders, but anxiety and depression disorders had no effect on the differences in the executive control network between the groups.

Radiotheragnostics Paradigm for Radioactive Iodine (Iodide) Management of Differentiated Thyroid Cancer

This review of radioactive iodide treatment (RAIT) extends from historical origins to its modern utilization in differentiated thyroid cancer (DTC). The principles embedded in the radiotheragnostics (RTGs) paradigm are detailed. The diverse approaches in current practice are addressed, and this broad variability represents a major weakness that erodes our specialty's trust-based relationship with patients and referring physicians. The currently developing inter-specialty collaboration should be hailed as a positive change. It promises to clarify the target-based terminology for RAIT. It defines RAIT of post total thyroidectomy (PTT), presumably benign thyroid as 'remnant ablation' (RA). 'Adjuvant treatment' (AT) referrers to RAIT of suspected microscopic DTC that is inherently occult on diagnostic imaging. RAIT directed at DTC lesion(s) overtly seen on diagnostic imaging is termed 'treatment of known disease' (TKD). It was recently recognized that a 'recurrent' DTC is actually occult residual DTC in the majority of cases. Thyroglobulin with remnant uptake concord (TRUC) method (aka Tulchinsky method) was developed to validate that a benign remnant in the post-thyroidectomy neck bed, as quantified by the RAI uptake, is concordant with a measured thyroglobulin (Tg) level at the time of the initial post-thyroidectomy evaluation. It allows recognition of occult residual DTC contribution to post-thyroidectomy Tg. Case examples demonstrate the application of the TRUC method for a logical selection of a specific RAIT category, using imaging-guided identification and management of RAI-avid versus RAI-nonavid residual DTC, i.e. the radiotheragnostics paradigm.

Diagnosis and treatment of hypothyroidism in the elderly

The global population is aging with millions of people today living into their 90 s. Thyroid disease, particularly hypothyroidism, is widespread among all age groups, and it is expected to steadily increase as the population gets older. Clinical diagnosis of hypothyroidism is challenging, as the TSH reference range needs to be evaluated according to age, while evaluation of TSH levels must also take into account body weight and other variants such as polypharmacy, comorbidities, and general health condition. Since thyroid hormone has a potent regulatory effect on cholesterol metabolism, the possibility of thyroid dysfunction should be considered in cases of unexplained dyslipidemia. Once hypothyroidism has been confirmed, treatment requires caution, frequent cardiovascular monitoring, and individualized (precision) medicine. Treatment of subclinical hypothyroidism (SCH) in the elderly should be undertaken with care, guided by age and the degree of SCH: a TSH higher than 10 mU/l seems a reasonable threshold, though it should be regularly re-evaluated, while the LT4 dose needs to be tailored, taking into account the patient's health condition and the potential presence of dyslipidemia as well as other metabolic derangements.

Regional Variation across Canadian Centers in Radioiodine Administration for Thyroid Remnant Ablation in Well-Differentiated Thyroid Cancer Diagnosed in 2000-2010

Background. Use of radioactive iodine (RAI) ablation has been reported to vary significantly between studies. We explored variation in RAI ablation care patterns between seven thyroid cancer treatment centers in Canada. Methods. The Canadian Collaborative Network for Cancer of the Thyroid (CANNECT) is a collaborative registry to describe and analyze patterns of care for thyroid cancer. We analyzed data from seven participating centers on RAI ablation in patients diagnosed with well-differentiated (papillary and follicular) thyroid cancer between 2000 and 2010. We compared RAI ablation protocols including indications (based on TNM staging), preparation protocols, and administered dose. We excluded patients with known distant metastases at time of RAI ablation. Results. We included 3072 patients. There were no significant differences in TNM stage over time. RAI use increased in earlier years and then declined. The fraction of patients receiving RAI varied significantly between centers, ranging between 20–85% for T1, 44–100% for T2, 58–100% for T3, and 59–100% for T4. There were significant differences in the RAI doses between centers. Finally, there was major variation in the use of thyroid hormone withdrawal or rhTSH for preparation of RAI ablation. Conclusion. Our study identified significant variation in use of RAI for ablation in patients with well-differentiated thyroid cancer both between Canadian centers and over time.

Impaired brain metabolism and neurocognitive function in childhood leukemia survivors despite complete hormone supplementation in adulthood

Cranial radiotherapy is a known risk factor for neurocognitive impairment in survivors of childhood acute lymphoblastic leukemia (ALL). Understanding the nature of cognitive dysfunction during adulthood in ALL survivors is important as it has an impact on major life situations. Thirty-eight (21 women) ALL survivors were investigated 34 years after diagnosis. Median-age was 38 (27-46) years. All were treated with a CRT dose of 24Gy and 11 years (3-13) of complete hormone supplementation. Comparisons were made to 29 matched controls. Assessments of magnetic resonance spectroscopy (white and grey matter metabolic alterations), brain volume and neuropsychological tests were performed. ALL survivors demonstrate a generally lower performance in neuropsychological tests. ALL survivors scored lower than controls in vocabulary (p<0.001), memory (p<0.001), learning capacity (p<0.001), spatial ability (p<0.001), executive functions and attention (p<0.001) 34 years after ALL treatment. Compared to controls ALL survivors had reduced white matter (WM) (492 vs 536cm³, p<0.001) and grey matter (GM) volumes (525 vs 555cm³, p=0.001). ALL survivors had lower levels of WM N-acetyl aspartate/creatin (NAA/Cr) (1.48 vs 1.63, p=0.004), WM NAA+NAAG (N-acetylaspartylglutamate)/Cr (1.61 vs 1.85, p<0.001) and lower levels of GM NAA/Cr (1.18 vs 1.30, p=0.001) and GM NAA+NAAG/Cr (1.28 vs 1.34, p=0.01) compared to controls. ALL survivors had higher levels in WM MI (Myoinositol)/NAA (0.65 vs 0.56, p=0.01) concentrations compared to controls. There was a significantly negative correlation of years since ALL diagnosis to WM NAA+NAAG/Cr (r=-0.4, p=0.04) in ALL survivors. The present study shows impaired brain metabolism detected by MRS, reduced brain volumes and neurocognitive impairment in childhood ALL survivors treated with cranial radiotherapy and chemotherapy, despite complete hormone substitution. We also report an impairment of metabolites correlated to time since treatment and a progressive impairment in sustained attention, suggesting an accelerated aging in the irradiated brain. Following these survivors many decades, or throughout life, after treatment with cranial radiotherapy and chemotherapy is highly warranted for a broader understanding of long-term outcome in this patient group.

Informed consent for low-risk thyroid cancer

Significant barriers to informed consent surround the clinical management of adult patients with well-differentiated thyroid cancer. The literature reveals lack of disclosure surrounding clinical equipoise; confusing and conflicting terminology; and an insufficient number of prospective trials with proper ethical oversight. We provide guidance for valid consent to treatment in this population, and propose stipulative definitions for a variety of terms used in this context. Three critical areas are addressed: surgical management, radioactive iodine management and nonvalidated practice. Sound ethical frameworks for valid consent in patients with low-risk thyroid cancer include consent to observational (or ‘active surveillance’) research protocols, consent to nonvalidated practice and consent when there are opposing standards of care due to insufficient data and disagreement among the community of experts.

Daytime somnolence as an early sign of cognitive decline in a community-based study of older people

OBJECTIVE

This study aimed to examine the association between self-reported sleep problems and cognitive decline in community-dwelling older people. We hypothesized that daytime somnolence predicts subsequent cognitive decline.

METHODS

This is a longitudinal study in a 3.2-year follow-up, with 18-month intervals. The setting is the Washington Heights-Inwood Community Aging Project. There were 1098 participants, who were over 65 years old and recruited from the community. Sleep problems were estimated using five sleep categories derived from the RAND Medical Outcome Study Sleep Scale: sleep disturbance, snoring, awaken short of breath/with a headache, sleep adequacy, and daytime somnolence. Four distinct cognitive composite scores were calculated: memory, language, speed of processing, and executive functioning. We used generalized estimating equations analyses with cognitive scores as the outcome, and time, sleep categories and their interactions as the main predictors. Models were initially unadjusted and then adjusted for age, gender, education, ethnicity, depression, and apolipoprotein E-ε4 genotype.

RESULTS

Increased daytime somnolence (including feeling drowsy/sleepy, having trouble staying awake, and taking naps during the day) was linked to slower speed of processing both cross-sectionally (B = -0.143, p = 0.047) and longitudinally (B = -0.003, p = 0.027). After excluding the demented participants at baseline, the results remained significant (B = -0.003, p = 0.021).

CONCLUSIONS

Our findings suggest that daytime somnolence may be an early sign of cognitive decline in the older population.

Is There Any Effect on Smell and Taste Functions with Levothyroxine Treatment in Subclinical Hypothyroidism?

Subclinical hypothyroidism has been accused for coronary heart disease, lipid metabolism disorders, neuropsychiatric disorders, infertility or pregnancy related problems with various strength of evidence. Currently there is insufficient knowledge about olfaction and taste functions in subclinical hypothyroidism. Aim of the present study is to investigate the degree of smell and taste dysfunction in patients with subclinical hypothyroidism. 28 subclinical hypothyroid patients, and 31 controls enrolled in the prospective study in Istanbul, Turkey. Subclinical hypothyroid patients were treated with L-thyroxine for 3 months. Psychophysiological olfactory testing was performed using odor dispensers similar to felt-tip pens (“Sniffin’ Sticks”, Burghart, Wedel, Germany). Taste function tests were made using "Taste Strips" (Burghart, Wedel, Germany) which are basically tastant adsorbed filter paper strip. Patients scored lower on psychophysical olfactory tests than controls (odor thresholds:8.1±1.0 vs 8.9±1.1, p = 0.007; odor discrimination:12.4±1.3 vs 13.1±0.9, p = 0.016; odor identification:13.1±0.9 vs 14.0±1.1, p = 0.001; TDI score: 33.8±2.4 vs 36.9±2.1, p = 0.001). In contrast, results from psychophysical gustatory tests showed only a decreased score for “bitter” in patients, but not for other tastes (5.9±1.8 vs 6.6±1.0, p = 0.045). Three month after onset of treatment olfactory test scores already indicated improvement (odor thresholds:8.1±1.0 vs 8.6±0.6, p<0.001; odor discrimination:12.4±1.31 vs 12.9±0.8, p = 0.011; odor identification:13.1±0.9 vs 13.9±0.8, p<0.001; TDI scores:33.8±2.4 vs 35.5±1.7, p<0.001) respectively. Taste functions did not differ between groups for sweet, salty and, sour tastes but bitter taste was improved after 3 months of thyroxin substitution (patients:5.9±1.8 vs 6.6±1.2, p = 0.045). Correlation of changes in smell and taste, with thyroid function test were also evaluated. TSH, fT4 were found have no correlation with smell and taste changes with treatment. However bitter taste found positively correlated with T3 with treatment(r: 0.445, p: 0.018). Subclinical hypothyroid patients exhibited a significantly decreased olfactory sensitivity; in addition, bitter taste was significantly affected. Most importantly, these deficits can be remedied on average within 3 months with adequate treatment.

Recombinant Human Thyroid Stimulating Hormone versus Thyroid Hormone Withdrawal for Radioactive Iodine Treatment of Differentiated Thyroid Cancer with Nodal Metastatic Disease

Introduction. Recombinant human thyroid stimulating hormone (rhTSH) is approved for preparation of thyroid remnant ablation with radioactive iodine (RAI) in low risk patients with well differentiated thyroid cancer (DTC). We studied the safety and efficacy of rhTSH preparation for RAI treatment of thyroid cancer patients with nodal metastatic disease. Methods. A retrospective analysis was performed on 108 patients with histopathologically confirmed nodal metastatic DTC, treated with initial RAI between January 1, 2000, and December 31, 2007. Within this selected group, 31 and 42 patients were prepared for initial and all subsequent RAI treatments by either thyroid hormone withdrawal (THW) or rhTSH protocols and were followed up for at least 3 years. Results. The response to initial treatment, classified as excellent, acceptable, or incomplete, was not different between the rhTSH group (57%, 21%, and 21%, resp.) and the THW group (39%, 13%, and 48%, resp.; P = 0.052). There was no significant difference in the final clinical outcome between the groups. The rhTSH group received significantly fewer additional doses of RAI than the THW group (P = 0.03). Conclusion. In patients with nodal-positive DTC, preparation for RAI with rhTSH is a safe and efficacious alternative to THW protocol.