Hashimoto's thyroiditis in patients with normal thyroid-stimulating hormone levels

Physical fatigability and muscle pain in patients with Hashimoto thyroiditis

Introduction

Hashimoto thyroiditis (HT) may lead to muscle weakness due to hypothyroid dysfunction. However, clinical experience treating patients with HT suggests that neuromuscular symptoms may develop in these patients despite long-standing euthyroidism.

Methods

In 24 euthyroid patients with HT and 25 healthy controls, physical fatigability was assessed using the arm movement test (AMT) and 6-min walk test (6MWT). Fatigability was based on calculation of linear trend (LT) reflecting dynamic performance within subsequent constant time intervals. Perception of physical fatigue and muscle pain was analyzed using fatigue (FSMC) and pain questionnaires. Obtained results were correlated with clinical, neurophysiological and lab findings.

Results

HT patients showed a negative LT in 6MWT significantly differing from stable performance in controls. LT in AMT did not differ between HT and controls. FSMC scores and pain perception revealed significantly higher levels in HT patients than in controls. Physical FSMC score was primarily influenced by pain perception (standardized regression coefficient, beta = 0.633, p = 0.002). Neither pain score nor physical fatigue score showed a correlation with LT in 6MWT nor did mood, or anti-TPO antibody titer.

Conclusion

A significant physical fatigability could be shown in euthyroid HT patients despite missing obvious neuromuscular deficits in routine testing. Further, elevated pain and fatigue perception in HT patients seem to contribute to nonspecific muscle complaints in these patients. A possible pathogenic role of thyroid autoimmunity in hidden neuromuscular involvement may be suggested.

Thyroidectomy Versus Medical Management for Euthyroid Patients With Hashimoto Disease and Persisting Symptoms: A Randomized Trial

BACKGROUND

Hashimoto disease is a chronic autoimmune thyroiditis. Despite adequate hormone substitution, some patients have persistent symptoms that may be the result of immunologic pathophysiology.

OBJECTIVE

To determine whether thyroidectomy improves symptoms in patients with Hashimoto thyroiditis who still have symptoms despite having normal thyroid gland function while receiving medical therapy.

DESIGN

Randomized trial. (ClinicalTrials.gov: NCT02319538).

SETTING

Secondary care hospital in Norway.

PATIENTS

150 patients aged 18 to 79 years with persistent Hashimoto-related symptoms despite euthyroid status while receiving hormone replacement therapy and with serum antithyroid peroxidase (anti-TPO) antibody titers greater than 1000 IU/mL.

INTERVENTION

Total thyroidectomy or medical management with hormone substitution to secure euthyroid status in both groups.

MEASUREMENTS

The primary outcome was general health score on the Short Form-36 Health Survey (SF-36) at 18 months. Secondary outcomes were adverse effects of surgery, the other 7 SF-36 subscores, fatigue questionnaire scores, and serum anti-TPO antibody titers at 6, 12, and 18 months.

RESULTS

During follow-up, only the surgical group demonstrated improvement: Mean general health score increased from 38 to 64 points, for a between-group difference of 29 points (95% CI, 22 to 35 points) at 18 months. Fatigue score decreased from 23 to 14 points, for a between-group difference of 9.3 points (CI, 7.4 to 11.2 points). Chronic fatigue frequency decreased from 82% to 35%, for a between-group difference of 39 percentage points (CI, 23 to 53 percentage points). Median serum anti-TPO antibody titers decreased from 2232 to 152 IU/mL, for a between-group difference of 1148 IU/mL (CI, 1080 to 1304 IU/mL). In multivariable regression analyses, the adjusted treatment effects remained similar to the unadjusted effects.

LIMITATION

Results are applicable only to a subgroup of patients with Hashimoto disease, and follow-up was limited to 18 months.

CONCLUSION

Total thyroidectomy improved health-related quality of life and fatigue, whereas medical therapy did not. This improvement, along with concomitant elimination of serum anti-TPO antibodies, may elucidate disease mechanisms.

PRIMARY FUNDING SOURCE

Telemark Hospital.

Thyroid Autoimmunity: Role of Anti-thyroid Antibodies in Thyroid and Extra-Thyroidal Diseases

Autoimmune diseases have a high prevalence in the population, and autoimmune thyroid disease (AITD) is one of the most common representatives. Thyroid autoantibodies are not only frequently detected in patients with AITD but also in subjects without manifest thyroid dysfunction. The high prevalence raises questions regarding a potential role in extra-thyroidal diseases. This review summarizes the etiology and mechanism of AITD and addresses prevalence of antibodies against thyroid peroxidase, thyroid-stimulating hormone receptor (TSHR), and anti-thyroglobulin and their action outside the thyroid. The main issues limiting the reliability of the conclusions drawn here include problems with different specificities and sensitivities of the antibody detection assays employed, as well as potential confounding effects of altered thyroid hormone levels, and lack of prospective studies. In addition to the well-known effects of TSHR antibodies on fibroblasts in Graves' disease (GD), studies speculate on a role of anti-thyroid antibodies in cancer. All antibodies may have a tumor-promoting role in breast cancer carcinogenesis despite anti-thyroid peroxidase antibodies having a positive prognostic effect in patients with overt disease. Cross-reactivity with lactoperoxidase leading to induction of chronic inflammation might promote breast cancer, while anti-thyroid antibodies in manifest breast cancer might be an indication for a more active immune system. A better general health condition in older women with anti-thyroid peroxidase antibodies might support this hypothesis. The different actions of the anti-thyroid antibodies correspond to differences in cellular location of the antigens, titers of the circulating antibodies, duration of antibody exposure, and immunological mechanisms in GD and Hashimoto's thyroiditis.

Overt hypothyroidism is associated with the presence of uterine leiomyoma: a retrospective analysis

OBJECTIVE

A possible correlation between uterine leiomyoma and thyroid disease was reported decades ago. We aimed to evaluate the possible associations between the presence of uterine leiomyomas and (i) the presence of overt hypothyroidism, (ii) the level of anti-thyroid peroxidase antibodies (TPO-Ab) and thyroglobulin antibodies (TG-Ab), and (iii) thyroid stimulating hormone (TSH) levels.

STUDY DESIGN

In a retrospective study, all 215 sterile women who underwent reproductive surgery (hysteroscopy and laparoscopy/laparotomy) at our department from January 2007 to January 2011 were included. All leiomyomas suspected on gynecologic ultrasound were verified during surgery. As risk factors for uterine leiomyomas, thyroid parameters, age, African heritage, age at menarche, parity, and body mass index were included.

RESULTS

One or more uterine leiomyomas were found in 51 cases (23.7%). After multivariate analysis, three parameters remained significant, with African heritage the most important (odds ratio, OR, 27.80), followed by overt hypothyroidism (OR 3.10) and increasing age (OR 1.23). Larger leiomyomas were found in women with overt hypothyroidism than in those without overt hypothyroidism (median, 70 mm; range, 5-88 vs. median, 30 mm; range, 2-93, respectively; p=0.007).

CONCLUSIONS

Overt hypothyroidism, but not autoantibodies against the thyroid gland, was associated with the presence of uterine leiomyoma in our study.