The impact of the SARS-CoV2 pandemic on the prescription of thyroid medication in Austria - A nationwide population-based registry analysis.

BACKGROUND: Case reports indicate a clinical connection between SARS-CoV-2 and thyroid dysfunctions. However, evidence from large population-based registry analyses is sparse, especially in Europe, where iodine deficiency is common. This study aimed to analyze the impact of the COVID-19 pandemic on healthcare provision for thyroid diseases in Austria. METHODS: We performed a retrospective, population-based registry analysis of the Austrian health insurance fund database, covering more than 9 million inhabitants. Data from all patients with prescriptions of thyroid-specific drugs and/or inpatient thyroid-related diagnoses from 2017 to 2019 (pre-pandemic years) were compared to 2020 and 2021 (pandemic years; characterized by high numbers of SARS-CoV2 infections and population-wide vaccination strategy). The incidence rates of thyroid medication prescriptions for hypothyroidism and hyperthyroidism were calculated for every year to evaluate the impact of the pandemic. RESULTS: The incidence rate for total thyroid medication prescription was 539.07/100,000 individuals (534.23-543.93 95%CI) in 2018 and declined during the pandemic (2020: 387.19/100,000 (383.12-391.29 95%CI); 2021: 336.90/100,000 (333.11-340.73 95%CI)). Similarly, the incidence rate for levothyroxine prescription was higher pre-pandemic (2018: 465.46/100,000 (460.97-469.98 95%CI) and declined during the pandemic (2020: 348.14/100,000 (344.28-352.03 95%CI); 2021: 300.30/100,000 (296.7-303.91 95%CI). The incidence rates of thiamazole prescriptions (2018: 10.24/100,000 (9.58-10.93 95%CI); 2020: 8.62/100,000 (8.03-9.26 95%CI); 2021: 11.17/100,000 (10.49-11.89 95%CI) were stable. CONCLUSIONS: These findings suggest no clinically significant impact of SARS-CoV2 and/or vaccination on thyroid function at a population level.

[Thyroid and SARS-CoV-2]. / Schilddrüse und SARS-CoV-2.

There are several interactions between a SARS-CoV­2 infection and the thyroid, bidirectionally in both directions. In severe COVID-19 infection, changes in thyroid hormone levels are a marker for poorer prognosis. SARS-CoV­2 appears to interact directly with thyrocytes as well as modulate the immune system and trigger autoimmune thyroid disease. As early as 2020, SARS-CoV­2 associated thyroiditis was described in patients with COVID-19, which is similar to subacute thyroiditis but typically painless. There are now a wide variety of reports on the occurrence of chronic autoimmune thyroiditis and Graves' disease following both viral infection and vaccination. Existing thyroid disease does not appear to be associated with either a higher risk of SARS-CoV­2 infection or a more severe disease course. The present paper summarizes the current knowledge regarding the thyroid gland and SARS-CoV­2.

Diagnostic Reference Levels for nuclear medicine imaging in Austria: A nationwide survey of used dose levels for adult patients.

PURPOSE: To assess dose levels in routine nuclear medicine (NUC) procedures in Austria as a prior to a legislative update of the National Diagnostic Reference Levels (NDRL). METHOD: As part of a nationwide survey of common NUC-examinations between June 2019 and November 2019, data sets were collected from 33 Austrian hospitals with NUC equipment. All hospitals were asked to report the NUC imaging devices in use (model, type, year of manufacture, detector material, collimators), the standard protocol parameters for selected examinations (standard activity, collimator, average acquisition time, reconstruction type, use of time-of-flight) and to report data from 10 representative examinations (e.g. injected activity, weight), incl. the most common NUC-examinations for planar imaging/SPECT and PET. Median/mean values for injected activity were calculated and compared to current Austrian and international NDRL. A Pearson correlation coefficient was computed comparing different variables. RESULTS: In total, all 33 hospitals (100% response rate) reported data for this study for 60 SPECT devices, 21 PET/CT devices and 23 scintigraphy devices. Fixed activity values for scintigraphy/SPECT and PET were employed by about 90% and 56% of the hospitals, respectively. The most widely performed examinations for scintigraphy/SPECT are bone imaging, thyroid imaging, renal imaging (with MAG3/EC) and lung perfusion imaging (in 88% of the hospitals) and F-18 FDG-PET studies for oncology indications (in 100% of the hospitals). Significant correlations were found for patient weight and injected activity (scintigraphy/SPECT), use of iterative reconstruction and injected activity (PET) as well as size of field-of-view and injected activity (PET). CONCLUSIONS: The reported injected activity levels were comparable to those in other countries. However, for procedures for which NDRL exist, deviations in injected activities of >20% compared to the NDRL were found. These deviations are assumed to result mainly from advances in technology but also from deviations between NDRL and prescribed activities as given in the information leaflets of the radiopharmaceuticals.

2021 European Thyroid Association Guidelines for the Management of Iodine-Based Contrast Media-Induced Thyroid Dysfunction.

Given the fact that a large number of radiological examinations using iodine-based contrast media (ICM) are performed in everyday practice, clinicians should be aware of potential ICM-induced thyroid dysfunction (TD). ICM can induce hyperthyroidism (Hyper) or hypothyroidism (Hypo) due to supraphysiological concentrations of iodine in the contrast solution. The prevalence of ICM-induced TD varies from 1 to 15%. ICM-induced Hyper is predominantly found in regions with iodine deficiency and in patients with underlying nodular goiter or latent Graves' disease. Patients at risk for ICM-induced Hypo include those with autoimmune thyroiditis, living in areas with sufficient iodine supply. Most cases of ICM-induced TD are mild and transient. In the absence of prospective clinical trials on the management of ICM-induced TD, an individualized approach to prevention and treatment, based on patient's age, clinical symptoms, pre-existing thyroid diseases, coexisting morbidities and iodine intake must be advised. Treatment of ICM-induced Hyper with antithyroid drugs (in selected cases in combination with sodium perchlorate) should be considered in patients with severe or prolonged hyperthyroid symptoms or in older patients with underlying heart disease. It is debated whether preventive therapy with methimazole and/or perchlorate prior to ICM administration is justified. In ICM-induced overt Hypo, temporary levothyroxine may be considered in younger patients with symptoms of Hypo, with an underlying autoimmune thyroiditis and in women planning pregnancy. Additional clinical trials with clinically relevant endpoints are warranted to further aid in clinical decision-making in patients with ICM-induced TD.

Effects of Thyroid Function on Phosphodiester Concentrations in Skeletal Muscle and Liver: An In Vivo NMRS Study.

CONTEXT: Thyroid function is clinically evaluated by determination of circulating concentrations of thyrotropin (thyroid-stimulating hormone; TSH) and free thyroxine (fT4). However, a tissue-specific effector substrate of thyroid function is lacking. Energy-rich phosphorus-containing metabolites (PM) and phospholipids (PL) might be affected by thyroid hormone action and can be noninvasively measured by 31P nuclear magnetic resonance spectroscopy (NMRS). OBJECTIVES: To measure the actions of peripheral thyroid hormones on PM and PL tissue concentrations. DESIGN AND SETTING: A longitudinal, prospective pilot study was performed. PARTICIPANTS: Nine patients with hyperthyroidism (HYPER) and 4 patients with hypothyroidism (HYPO) were studied at baseline and 3 months after treatment. MAIN OUTCOME MEASURES: High-field 1H/31P NMRS was used to assess profiles of PM, PL, and flux through oxidative phosphorylase in liver and skeletal muscle, as well as ectopic tissue lipid content. RESULTS: The concentrations of total skeletal muscle (m-) and hepatic (h-) phosphodiesters (PDE) and one of the PDE constituents, glycerophosphocholine (GPC), were lower in HYPER compared with HYPO (m-PDE: 1.4 ±â€…0.4 mM vs 7.4 ±â€…3.5 mM, P = 0.003; m-GPC: 0.9 ±â€…0.3 mM vs 6.7 ±â€…3.5 mM, P = 0.003; h-PDE: 4.4 ±â€…1.4 mM vs 9.9 ±â€…3.9 mM, P = 0.012; h-GPC: 2.2 ±â€…1.0 mM vs 5.1 ±â€…2.4 mM, P = 0.024). Both h-GPC (rho = -0.692, P = 0.018) and h-GPE (rho = -0.633, P = 0.036) correlated negatively with fT4. In muscle tissue, a strong negative association between m-GPC and fT4 (rho = -0.754, P = 0.003) was observed. CONCLUSIONS: Thyroxine is closely negatively associated with the PDE concentrations in liver and skeletal muscle. Normalization of thyroid dysfunction resulted in a decline of PDE in hypothyroidism and an increase in hyperthyroidism. Thus, PDE might be a sensitive tool to estimate tissue-specific peripheral thyroid hormone action.

Ultrasound criteria for risk stratification of thyroid nodules in the previously iodine deficient area of Austria - a single centre, retrospective analysis.

BACKGROUND: We aimed to study the validity of six published ultrasound criteria for risk stratification of thyroid nodules in the former severely iodine deficient population of Austria. METHODS: Retrospective, single centre, observer blinded study design. All patients with a history of thyroidectomy due to nodules seen in the centre between 2004 and 2014 with preoperative in-house sonography and documented postoperative histology were analyzed (n = 195). A board of five experienced thyroidologists evaluated the images of 45 papillary carcinomas, 8 follicular carcinomas, and 142 benign nodules regarding the following criteria: mild hypoechogenicity, marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, taller than wide shape, missing thin halo. RESULTS: All criteria but mild hypoechogenicity were significantly more frequent in thyroid cancer than in benign nodules. The number of positive criteria was significantly higher in cancer (2.79 ± 1.35) than in benign nodules (1.73 ± 1.18; p < 0.001). Thus, with a cut-off of two or more positive criteria, a sensitivity of 85% and a specificity of 45% were reached to predict malignancy in this sample of thyroid nodules. As expected, the findings were even more pronounced in papillary cancer only (2.98 ± 1.32 vs. 1.73 ± 1.18, p < 0.001). The six ultrasound criteria could not identify follicular cancer. CONCLUSION: Our findings support the recently published EU-TIRADS score. Apart from mild hypoechogenicity, the analyzed ultrasound criteria can be applied for risk stratification of thyroid nodules in the previously severely iodine deficient population of Austria.

[123I]-beta-CIT SPECT imaging shows reduced thalamus-hypothalamus serotonin transporter availability in 24 drug-free obsessive-compulsive checkers.

Numerous findings indicate alterations in brain serotonin systems in obsessive-compulsive disorder (OCD). We investigated the in vivo availability of thalamus-hypothalamus serotonin transporters (SERT) in patients with DSM-IV OCD who displayed prominent behavioral checking compulsions (OC-checkers). Four hours after injection of [(123)I]-2beta-carbomethoxy-3beta-(4-iodophenyl)tropane ([(123)I]-beta-CIT), single photon emission computed tomography (SPECT) scans were performed in 24 medication-free non-depressed OC-checkers and 24 age- and gender-matched healthy controls. For quantification of brain serotonin transporter availability, a ratio of specific to non-displaceable [(123)I]-beta-CIT brain binding was used (V''(3)=(thalamus and hypothalamus-cerebellum)/cerebellum). Drug-free non-depressed OC-checkers showed an 18% reduced brain serotonin transporter availability in the thalamus and hypothalamus, as compared with healthy control subjects (1.38+/-0.19 vs 1.69+/-0.21; p<0.001). There was a strong negative correlation between severity of OC symptomatology (Y-BOCS scores) and SERT availability (r=-0.80; p<0.001). Moreover, we found a significant positive correlation between illness duration and serotonin transporter availability (r=0.43; p<0.05). This first report of significantly reduced [(123)I]-beta-CIT binding in the thalamus-hypothalamus region in OC-checkers suggests reduced brain serotonin transporter availability, which is more pronounced with increased severity of OC symptomatology and short duration of illness. The results provide direct evidence for an involvement of the serotonergic system in the pathophysiology of OCD.

Long term control of hypercortisolism with fluconazole: case report and in vitro studies.

OBJECTIVES: To evaluate the efficacy of fluconazole as an alternative treatment for controlling hypercortisolism in Cushing's syndrome and to determine its effect on glucocorticoid production in vitro. DESIGN: Case report and in vitro study in a University Clinic. CASE: An 83 year old patient presented with recurrence of Cushing's syndrome due to pulmonary metastases three years after unilateral adrenalectomy. During a near fatal episode of sepsis she was started on fluconazole 200 mg/day intravenously which normalised cortisol excretion. The therapy was continued orally for 18 months. Upon temporary discontinuation and reintroduction of treatment, cortisol levels increased and normalized, respectively. At month 16, fluconazole had to be increased to a dose of 400 mg/day to keep cortisol excretion in the normal range. Disease progression was slow and no side effects occurred. IN VITRO RESULTS: Fluconazole in a concentration of 500 microM nearly abolished corticosterone production over 24 h from the adrenal adenoma cell line Y-1 (8.6 +/- 0.5% compared with control, P < 0.0001) and significantly reduced corticosterone production in concentrations of 50 microM (48.3 +/- 1.9% vs. control, P < 0.0001) and 5 microM (80.5 +/- 8.5% vs. control, P < 0.05). CONCLUSION: These results demonstrate for the first time that fluconazole normalises cortisol concentrations in vivo in a patient with Cushing's syndrome with adrenal carcinoma and inhibit glucocorticoid production in vitro in a cell line. Thus, fluconazole might be useful in controlling glucocorticoid excess in Cushing's syndrome and because of its lower toxicity might be preferable to ketoconazole.

Frequency and relevance of elevated calcitonin levels in patients with neoplastic and nonneoplastic thyroid disease and in healthy subjects.

Routine measurement of serum calcitonin (CT) has been recently proposed for all patients with neoplastic thyroid disease to detect clinically occult medullary thyroid carcinoma (MTC). Data on the prevalence of elevated CT levels in nonneoplastic thyroid disease or in healthy subjects have not been reported to date. Four hundred and fourteen consecutive patients with suspected thyroid disease and 362 healthy controls underwent thyroid examination with measurement of basal serum CT. Whenever serum CT was 10 pg/ml or more, a pentagastrin (PG) stimulation test was performed. Twenty-eight of 414 patients (6.8%) showed elevated basal serum CT levels, 15 of them with nonneoplastic thyroid disease, and the remaining 13 subjects with neoplastic thyroid disease. Four patients with abnormal PG testing (stimulated CT, > or = 100 pg/ml) were identified. Three of them had biochemical and sonographical evidence of thyroiditis. Elevated basal CT levels were significantly more frequent in patients with Hashimoto's thyroiditis (HT; P < 0.05). One female patient with HT had a 5-mm nodule, which was classified as MTC. None of the 6 out of 362 healthy controls with elevated basal CT (1.7%) presented an abnormal PG test. Our data suggest that basal CT measurements can be of use in the detection/screening of MTC not only in subjects with neoplastic thyroid disorders, but also in patients with immunological evidence of HT. They also confirm earlier reports on the essential value of PG stimulation testing, even when basal plasma CT levels are only modestly elevated, with regard to establishing the diagnosis of MTC or its premalignant associated conditions (micro-MTC and neoplastic C cell hyperplasia).

Follicular variant of papillary thyroid carcinoma: a long-term follow-up.

HYPOTHESIS: The clinical behavior of the follicular variant of papillary thyroid carcinoma (FVPTC) is similar to pure papillary thyroid carcinoma (PPTC) and completely different from follicular thyroid carcinoma (FTC). DESIGN: Retrospective analysis of prospectively documented data. SETTING: Referral center of a university hospital. PATIENTS: Two hundred thirty-seven consecutive patients with follicular cell-derived thyroid carcinomas were operated on in our institution during a 15-year period, from January 1, 1980, to December 31, 1994. Of the 154 PTC patients, 37 (24%) had FVPTC. The mean follow-up was 128.2 months (10.7 years). MAIN OUTCOME MEASURES: Demographic features, tumor characteristics, local and distant spread, persistence or recurrence of disease, and carcinoma-related mortality were compared between the groups with FVPTC, PPTC, and non-Hürthle cell FTC (NHFTC). RESULTS: The frequency of multicentricity was significantly higher in the FVPTC group than in the PPTC group (P =.03) or in the NHFTC group (P =.01) (12 [32%] of 37 patients vs 17 [15%] of 117 patients vs 6 [10%] of 58 patients, respectively). The incidence of cervical lymph node metastases was lower in the FVPTC group than in the PPTC group (P =.30) and higher than in NHFTC group (P =.004) (12 [32%] of 37 patients vs 53 [45%] of 117 patients vs 6 [10%] of 58 patients, respectively). At diagnosis, no patient with FVPTC showed distant metastases, compared with 5 patients (4%) with PPTC (P =.34) and 19 (33%) with NHFTC (P<.001). There was no carcinoma-related death in the FVPTC group. The strikingly poorer prognosis for the NHFTC group was statistically significant (P<.001), whereas the difference in carcinoma-specific survival between the PPTC and the FVPTC groups did show a trend toward better survival in the FVPTC group. CONCLUSION: The clinical behavior of the FVPTC group did not differ significantly from that of the PPTC group, whereas compared with the NHFTC group, the FVPTC group showed statistically significant differences for most of the analyzed variables.

The importance of delayed images in gastrointestinal bleeding scintigraphy.

Although radionuclide methods for the detection of gastrointestinal (GI) bleeding have been available for more than 20 years, the value of delayed images in GI bleeding scintigraphy is still regarded controversially. The aim of this study was to determine the value of delayed images in a group of patients with predominantly low-grade intermittent bleeding. Eighty-nine consecutive GI bleeding scintigraphies of 75 patients were analysed retrospectively. All patients were referred to our department after other diagnostic methods had failed to identify the localization of GI bleeding. After the dynamic study, delayed images were acquired for up to 24 h until a bleeding site was identified. Data on the clinical outcome were available in all but five patients. No patient with a negative scan died from GI bleeding. A positive result was found in 41 patients (55%). The scans of 11 of these 41 patients (27%) became positive during dynamic imaging. Four required immediate surgery and, in another patient, surgery was not performed because of diffuse bleeding of the entire GI tract. One patient died without surgical intervention. Thirty-three scans of 30 of these 41 patients (73%) were positive on delayed imaging only, leading to surgery in 12 individuals. Our findings demonstrate the importance of delayed images in GI bleeding scintigraphy. Many of our patients who required surgery had scans that did not become positive for several hours.

SPECT-CT for topographic mapping of sentinel lymph nodes prior to gamma probe-guided biopsy in head and neck squamous cell carcinoma.

INTRODUCTION: Lymphoscintigraphic planar imaging is a common procedure for sentinel lymph node imaging prior to lymph node biopsy, but fails to elucidate the specific lymphatic drainage. Composite functional/anatomical imaging (SPECT-CT) has the potential to enhance topographic orientation and diagnostic sensitivity of sentinel lymph node imaging, but has not yet been applied in the head and neck region. STUDY DESIGN: A total of 30 patients were investigated. Planar imaging was 5 min, 265 x 265, right and left lateral; 500 kilocounts (Kcts) and SPECT (GE Millenium VG Hawk Eye 6 degrees/30s. step, 128 x 128, slice thickness 4.42 mm). Scans were performed 60 min after intra-mucodermal injection of 0.1 ml of 20 MBq 99mTc nanocolloid in patients with squamous cell cancer of the head and neck. SPECT studies were analysed by filtered back projection (FBP: Hann (0.7) prefiltering, Butterworth (0.5) postfiltering) and reconstruction (OSEM: Post Filter Hamming (0.85), 2 Iterations) and independently viewed with the co-registered CT image (eNTEGRA Functional Anatomical Fusion Vers 2.0216). The results were validated by comparing the results of each method employed in all 30 cases and intraoperative gamma probe-guided sentinel lymph node biopsy with histological examination in 13 of these patients. RESULTS: The majority of patients had more than one sentinel node (mean 1.63, min. 0, max. 4). Seven out of the 30 studies demonstrated lymphatic flow to the contralateral side of the neck. Forty-nine sentinel nodes were identified by iteratively reconstructed SPECT-CT. Thirty-eight out of these 49 could be located in lymphoscintigraphic planar imaging, whereas only 24/49 were detected in filtered back projection, respectively. In 11 of the 30 cases, a clinically unpredictable pattern of lymphatic drainage was observed. No correlation was found between T stage or tumour location and the number of sentinel nodes detected. In one out of the 13 cases, in whom imaging was followed by intraoperative gamma probe-guided biopsy, no sentinel node could be detected with the probe in the proximity of the primary tumour, although the node was clearly discernible in the reconstructed SPECT-CT. CONCLUSION: Composite functional/anatomical imaging (SPECT-CT) is feasible for sentinel lymph node detection. It enhances topographic orientation and diagnostic sensitivity with more sentinel nodes being detectable than by planar lymphoscintigraphy alone. Planar imaging should be accompanied by iterative reconstructed SPECT-CT to identify lymph nodes adjacent to the primary lesion. Such nodes are easily overlooked by planar lymphoscintigraphy and intraoperative gamma probes, as the high activity at the injection site can obscure their detection.

Appointments at a thyroid outpatient clinic and the lunar cycle.

INTRODUCTION: Several variables of health-related human behaviour have been analysed with regard to a possible association with lunar phases. The aim of this study was to evaluate a possible relation between the lunar cycle and the number of requests for appointments at an outpatient clinic. This variable has not been studied hitherto. METHODS: We analysed a total number of 11,413 requests for appointments at our thyroid outpatient clinic during one year. Access to this clinic is not restricted, and all patients with known or suspected thyroid disease living in the area of Vienna may ask for an appointment. During the study period, 8,852 patients requested a follow-up appointment, and 2561 patients asked for a new appointment. We analysed a possible cyclic pattern in these requests using a nonlinear regression model based on both groups of patients. RESULTS: A cosinus curve with a period of 29.531 days (the mean length of a lunar cycle) was significantly associated with the number of requests for both follow-up appointments (p = 0.007) and new appointments (p = 0.001). Requests for follow-up appointments had their highest peaks three days after the full moon, whereas requests for new appointments were most frequent five days afterwards. CONCLUSION: Our findings suggest that lunar phases may affect patients' requests for appointments at a thyroid outpatient clinic. To the best of our knowledge, this is the first study reporting a possible association between health-related behaviour and lunar phases using requests for appointments as a relevant variable. There is a need for more research into the mechanism underpinning this behaviour.

Comparison of three different purification methods for the routine preparation of [11C] Metomidate.

PET with (R)-[O-methyl-11C] metomidate ([11C] MTO) is an attractive method for the characterisation of adrenal masses discriminating lesions of adrenal cortical origin from noncortical lesions. [11C] MTO was prepared by the reaction of [11C] methyliodide with the corresponding free acid. Three purification methods have been compared. The method of choice uses preparative HPLC with a ready-to-use weak acidic solvent.

The labelling of Nanocoll with [111In] for dual-isotope scanning.

UNLABELLED: Visualization and biopsy of sentinel lymph nodes play an important role in planning and controlling the therapy of breast cancer. Hitherto two methods-scintigraphy or gamma probe detection after injection of [99mTc]-nanocolloids and visual detection after injection of patent blue dye-are used routinely. There are no conclusive publications elucidating such important parameters as injection site, injection method and colloidal parameters. The present work aims to label Nanocoll with [111In] to provide an alternative method, a simultanous one-compound dual-isotope application. METHODS: [111In]-Indiumchloride was buffered with acetate and transferred to the nanocolloid. The colloid labelling reaction was complete after 30 min and filtrated through 100 nm Nuclepore filters. RESULTS: Incorporation yield of [111In]-Indium into the nanocolloid was nearly quantitative, the step associated with the major loss of activity was the particle sizing with a mean yield of 55%. CONCLUSION: The presented method allows for the routine supply of [111In]-nanocolloids. Size-filtered [111In]-Nanocoll shows the same particle size range as [99mTc]-Nanocoll.

Coronary vasoreactivity in subjects with thyroid autoimmunity and subclinical hypothyroidism before and after supplementation with thyroxine.

BACKGROUND: The association of subclinical hypothyroidism (SCH) with increased risk for cardiovascular disease is still controversial. This study aimed to examine coronary vascular reactivity by positron emission tomography (PET) in asymptomatic patients with SCH before and after levothyroxine (LT4) supplementation. METHODS: Ten patients (7 women and 3 men; mean age 43±15 years) with untreated autoimmune SCH, defined by elevated levels of thyroid-stimulating hormone (mean TSH: 16.9±11.3 µU/mL), normal levels of free thyroxine (0.9±0.1 µg/mL), free triiodothyronine (3.2±0.4 pg/mL), and positive thyroid peroxidase antibodies were studied. Eight euthyroid subjects with similar low-risk cardiovascular risk profile served as controls. Myocardial blood flow (MBF) and coronary flow reserve (CFR) were quantitatively assessed with rest/stress N-13 ammonia PET at baseline and after 6 months of LT4 replacement therapy (given only to patients). RESULTS: At baseline, stress MBF and CFR corrected (c) for rate pressure product (RPP) and myocardial vascular resistance (MVR) during stress were significantly reduced in SCH compared with controls (stress MBF: 2.87±0.93 vs. 4.79±1.16 mL/g/min, p=0.003; CFR: 2.6±0.73 vs. 4.66±1.38, p=0.004; MVR: 40.14±18.76 vs. 20.47±6.24 mmHg/mL/min, p=0.02). Supplementation therapy with LT4 normalized TSH in all subjects and was associated with an increase in CFR (2.6±0.73 vs. 3.81±1.19, p=0.003) and with a tendency toward a decrease in MVR. Differences in CFR between SCH and controls were also seen after correction of resting MBF for RPP. CONCLUSIONS: In asymptomatic subjects with SCH due to thyroid autoimmunity, coronary microvascular function is impaired and improves after supplementation with LT4. This may partially explain the increased cardiovascular risk attributed to SCH.

Diencephalic serotonin transporter availability predicts both transporter occupancy and treatment response to sertraline in obsessive-compulsive checkers.

BACKGROUND: To our knowledge, no studies have investigated the predictive value of central serotonin transporter (SERT) availability for treatment response to serotonin reuptake inhibitors (SSRIs) in patients with obsessive-compulsive disorder (OCD). This study used brain imaging to examine the relationship between pretreatment SERT availability and transporter occupancy as well as treatment response by sertraline in patients displaying prominent behavioral checking compulsions (OC checkers). METHODS: Single photon emission computed tomography (SPECT) was used to measure thalamic-hypothalamic SERT availability with [(123)I]-2beta-carbomethoxy-3beta-(4-iodophenyl)-tropane in 28 nondepressed OC checkers at baseline and after 14 weeks of treatment with sertraline (175 mg daily). SERT availability was correlated with OC severity and treatment response as assessed with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Associations between individual transporter occupancies and clinical parameters were investigated. RESULTS: 1) Correlation analyses between thalamic-hypothalamic SERT availability and OC severity showed significant negative associations at baseline and after treatment with sertraline. 2) Pretreatment SERT availability correlated significantly with both transporter occupancy and treatment response; in addition, a positive association was found between transporter occupancy and treatment response directly. 3) Using multivariate statistical models, the data demonstrated that higher pretreatment SERT availability significantly predicted higher occupancy rates as well as better treatment response 14 weeks later. CONCLUSIONS: Higher pretreatment thalamic-hypothalamic SERT availability may predict both higher occupancy rates and better treatment response to sertraline. The data suggest a strong connection between transporter occupancy and treatment response.