Association of Decreased Muscle Mass with Reduced Bone Mineral Density in Patients with Graves’ disease

Background The bone mineral density (BMD) did not increase significantly after the normalization of serum thyroid hormone levels. Studies on the effect of muscle mass on BMD in patients with Graves’ disease are scarce. This study aimed to determine the association of decreased muscle mass with reduced bone mineral density in patients with Graves’ disease. Methods A total of 758 patients with Graves’ at diagnosis (mean age 41.2 years) were enrolled for a cross-sectional study; of these, 287 patients were enrolled for a cohort study with a median follow-up of 24 months. Meanwhile, 1164 age- and sex-matched healthy controls participants were recruited. All participants underwent dual-energy x-ray absorptiometry and muscle mass index (ASMI) measurements. The changes in ASMI and BMD were calculated from the measurements made at a gap of 2 years. Results Compared with healthy controls participants, the BMD was still significantly lower after normalizing serum thyroid hormone levels (1.131 ± 0.268 vs. 1.07 ± 0.133, p < 0.05). ASMI was positively related to BMD in patients with Graves’ disease(lumbar BMD, r = 0.210; femoral neck BMD, r = 0.259;hip BMD, r = 0.235;P < 0.001) and this relationship still existed after successful anti-thyroid therapy(lumbar BMD, r = 0.169; femoral neck BMD, r = 0.281;hip BMD, r = 0.394;P < 0.001). Low muscle mass was associated with low BMD (OR, 1.426; 95% CI, 1.019–1.994). Moreover, improving the muscle mass led to changes in the bone mass of the femoral neck (OR, 0.420; 95% CI, 0.194–0.911) and hip (OR, 0.217; 95% CI, 0.092–0.511) during the follow-up period. However, this phenomenon was not observed in lumbar, and bone turnover markers. Conclusions The recovery of bone mass might be related to the recovery of muscle mass. Improving muscle mass might bring about changes in the bone mass of the femoral neck and hip. A site-related discrepancy was also observed. Patients with Graves’ disease should be helped in recovering muscle mass while administering anti-thyroid therapy.

Effects of Daily Kelp (Laminaria japonica) Intake on Body Composition, Serum Lipid Levels, and Thyroid Hormone Levels in Healthy Japanese Adults: A Randomized, Double-Blind Study

To investigate whether supplementation with iodine-reduced kelp (Laminaria japonica) powder decreases body fat composition in overweight Japanese subjects, a randomized, double-blind, placebo-controlled intervention study was conducted in 50 Japanese subjects with body mass index (BMI) ≥25 and <30 kg/m2. Subjects were randomly assigned to consume thirty tablets/d (10 tablets orally, 3 times/d) containing either iodine-reduced kelp powder (test, 6 g kelp powder corresponding to 3 g alginate/d) or kelp-free powder (placebo) for 8 weeks. Anthropometric measurements, blood lipids, and serum thyroid hormone levels were obtained before and after the trial. Body fat percentage was significantly decreased in male subjects from the test group compared with the placebo group. The same tendency was observed for body weight (p = 0.065) and BMI (p = 0.072) in male subjects. No significant changes in anthropometric measurements or visceral fat area were observed in female subjects. Serum thyroid hormone concentrations did not increase after 1.03 mg/d of iodine supplementation through kelp intake. The intake of iodine-reduced kelp powder led to significant and safe reductions in body fat percentage in overweight male subjects. The consumption of kelp high in alginate may contribute to preventing obesity without influencing thyroid function in Japanese subjects with a relatively high intake of iodine from seaweed.

Very rare case of Graves’ disease with resistance to methimazole: a case report and literature review

Background Methimazole (MMI) is used to treat hyperthyroidism in Graves’ disease. It is rare to encounter patients in whom hyperthyroidism cannot be controlled using high doses of MMI. Case presentation: A 21-year-old woman was referred to our hospital because of MMI-resistant Graves’ disease. Although her MMI dose had been increased to 120 mg/day, her serum thyroid hormone concentration was too high to be measured. Additional therapy with lithium carbonate, and then with dexamethasone and inorganic iodine, was initiated. After 14 days, the patient’s serum thyroid hormone concentration normalized, while she was taking 150 mg/day MMI, 800 mg/day lithium carbonate, 6 mg/day dexamethasone and 306 mg/day inorganic iodine, and total thyroidectomy was then performed. The patient was discharged 8 days after the thyroidectomy and experienced no major complications. Conclusions We have presented a rare case of Graves’ disease that was resistant to high-dose MMI. Combination therapy of MMI with lithium carbonate, dexamethasone and inorganic iodine may represent a therapeutic option for the preoperative preparation of patients with MMI-resistant Graves’ disease.

Improvement of the clinical signs of gait abnormality after treatment with levothyroxine in a horse with shivering and hypothyroidism

An 11-year-old Hanoverian gelding used for jumping was evaluated for gait abnormalities and hoof problems in the hindlimbs. Clinical examinations revealed signs consistent with shivers. A thyroid gland enlargement was noticed, baseline serum thyroid hormone (TH) concentrations were low, and a low response to thyrotropin-releasing hormone administration was observed. Hypothyroidism was suspected. The horse was treated with levothyroxine for 1 year. TH concentrations returned to the normal range by week 4 of treatment. Thirty weeks after the initiation of levothyroxine therapy, the gait abnormality improved. Our findings suggest that the assessment of thyroid status and especially of the subclinical thyroid gland disorders in horses affected with shivering, as well as evaluation of the effects of levothyroxine on the improvement of clinical signs could be promising in establishing the aetiopathogenesis and/or treatment of shivering in horses.

Duration of Exposure to Thyrotoxicosis Increases Mortality of Compromised AIT Patients: the Role of Early Thyroidectomy

Context Patients with amiodarone-induced thyrotoxicosis (AIT) and severely reduced left ventricular ejection fraction (LVEF) have a high mortality rate that may be reduced by total thyroidectomy. Whether in this subset of patients thyroidectomy should be performed early during thyrotoxicosis or later after restoration of euthyroidism has not yet been settled. Objectives Mortality rates, including peritreatment mortality and 5-year cardiovascular mortality, and predictors of death, evaluated by Cox regression analysis. Methods Retrospective cohort study of 64 consecutive patients with AIT selected for total thyroidectomy from 1997 to 2019. Four groups of patients were identified according to serum thyroid hormone concentrations and LVEF: Group 1 (thyrotoxic, LVEF &lt;40%), Group 2 (thyrotoxic, LVEF ≥40%), Group 3 (euthyroid, LVEF &lt; 40%), Group 4 (euthyroid, LVEF ≥40%). Results Among patients with low LVEF (Groups 1 and 3), mortality was higher in patients undergoing thyroidectomy after restoration of euthyroidism (Group 3) than in those submitted to surgery when still thyrotoxic (Group 1): peritreatment mortality rates were 40% versus 0%, respectively (P = .048), whereas 5-year cardiovascular mortality rates were 53.3% versus 12.3%, respectively (P = .081). Exposure to thyrotoxicosis was longer in Group 3 than in Group 1 (112 days, interquartile range [IQR] 82.5-140, vs 76 days, IQR 24.8-88.5, P = .021). Survival did not differ in patients with LVEF ≥40% submitted to thyroidectomy irrespective of being thyrotoxic (Group 2) or euthyroid (Group 4): in this setting, peritreatment mortality rates were 6.3% versus 4% (P = .741) and 5-year cardiovascular mortality rates were 12.5% and 20% (P = .685), respectively. Age (hazard ratio [HR] 1.104, P = .029) and duration of exposure to thyrotoxicosis (HR 1.004, P = .039), but not presurgical serum thyroid hormone concentrations (P = .577 for free thyroxine, P = .217 for free triiodothyronine), were independent predictors of death. Conclusions A prolonged exposure to thyrotoxicosis resulted in increased mortality in patients with reduced LVEF, which may be reduced by early thyroidectomy.