Blog
About

10
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Thyroid Hormone Replacement in Patients Following Thyroidectomy for Thyroid Cancer

      , M.D, , M.D., Ph.D. *

      , M.D., Ph.D., , M.D.

      Rambam Maimonides Medical Journal

      Rambam Health Care Campus

      Hypothyroidism, thyroid cancer, thyroid hormone, thyroid replacement, thyroid therapy, thyroidectomy

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Thyroid hormone replacement therapy in patients following thyroidectomy for thyroid cancer, although a potentially straightforward clinical problem, can present the clinician and patient with a variety of challenges. Most often the problems are related to the dose and preparation of thyroid hormone (TH) to use. Some patients feel less well following thyroidectomy and/or radioiodine ablation than they did before their diagnosis. We present evidence that levothyroxine (L-T4) is the preparation of choice, and keeping the thyroid-stimulating hormone (TSH) between detectable and 0.1 mU/L should be the standard of care in most cases. In unusual circumstances, when the patient remains clinically hypothyroid despite a suppressed TSH, we acknowledge there may be as yet unidentified factors influencing the body’s response to TH, and individualized therapy may be necessary in such patients.

          Related collections

          Most cited references 43

          • Record: found
          • Abstract: found
          • Article: not found

          Mechanisms of thyroid hormone action.

           David A Brent (2012)
          Our understanding of thyroid hormone action has been substantially altered by recent clinical observations of thyroid signaling defects in syndromes of hormone resistance and in a broad range of conditions, including profound mental retardation, obesity, metabolic disorders, and a number of cancers. The mechanism of thyroid hormone action has been informed by these clinical observations as well as by animal models and has influenced the way we view the role of local ligand availability; tissue and cell-specific thyroid hormone transporters, corepressors, and coactivators; thyroid hormone receptor (TR) isoform-specific action; and cross-talk in metabolic regulation and neural development. In some cases, our new understanding has already been translated into therapeutic strategies, especially for treating hyperlipidemia and obesity, and other drugs are in development to treat cardiac disease and cancer and to improve cognitive function.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Psychological well-being in patients on 'adequate' doses of l-thyroxine: results of a large, controlled community-based questionnaire study.

            Over 1% of the UK population is receiving thyroid hormone replacement with l-thyroxine (T4). However, many patients complain of persistent lethargy and related symptoms on T4 even with normal TSH levels. To date there has been no large study to determine whether this is related to thyroxine replacement or coincidental psychological morbidity. We have therefore attempted to address this issue using a large, community-based study. Computerized prescribing records of five general practices were used to identify 961 patients who had been on thyroxine for a minimum of 4 months from a population of 63 000 (1.5%), along with age- and sex-matched controls. All 1922 individuals were sent a two-page questionnaire, made up of the short form of the General Health Questionnaire (GHQ-12), designed to detect minor psychiatric disorders in the community, and a 12-question 'thyroid symptom questionnaire' (TSQ) in the same format. A covering letter explained that we were interested in 'how patients felt on medication' and made no direct reference to thyroxine. Scores from the GHQ and TSQ were marked for each individual using the GHQ and Likert scoring methods. Patients' latest TSH measurements were obtained from laboratory records. Comparisons were then made on scores for the total GHQ-12, TSQ and individual questions between patients (P) and control (C) groups. Separate analyses were made comparing the patients with a normal TSH (nP) and the control group. Five hundred and ninety-seven (62%) of the patients (P) and 551 (57%) of the controls (C) responded and fully completed at least one of the two questionnaire. Three hundred and ninety-seven responding patients (nP) had a TSH estimation performed in the previous 12 months with the last result being in the local laboratory normal range for TSH (0.1-5.5 or 0.2-6.0 mU/l, according to the assay method used). The responding P, nP and C populations were well matched for age (59.96, 59.73, 59.35 years) and sex (85%, 83%, 87% female). The number of individuals scoring 3 or more on the GHQ-12 (indicating 'caseness') was 21% higher in P than C [185/572 (32.3%) vs. 137/535 (25.6%), P = 0.014] and 26% higher in nP than C [131/381 (34.4%) vs. 137/535 (25.6%), P < 0.005]. Stronger differences were seen with the TSQ scores [C = 187/535 (35.0%), P = 273/583 (46.8%), P < 0.001, P vs. C; and nP = 189/381 (48.6%), P < 0.001, nP vs. C]. Differences existed in chronic drug use and chronic disease prevalence between the control and patient groups, but the differences in GHQ and TSQ scores between the groups remained significant even after correction for these factors as well as age and sex in multiple regression analysis. This community-based study is the first evidence to indicate that patients on thyroxine replacement even with a normal TSH display significant impairment in psychological well-being compared to controls of similar age and sex. In view of the large numbers of people on thyroxine replacement, we believe that these differences, although not large, could contribute to significant psychological morbidity in a substantial number of individuals.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Timing and magnitude of increases in levothyroxine requirements during pregnancy in women with hypothyroidism.

              Hypothyroidism during pregnancy has been associated with impaired cognitive development and increased fetal mortality. During pregnancy, maternal thyroid hormone requirements increase. Although it is known that women with hypothyroidism should increase their levothyroxine dose during pregnancy, biochemical hypothyroidism occurs in many. In this prospective study we attempted to identify precisely the timing and amount of levothyroxine adjustment required during pregnancy. Women with hypothyroidism who were planning pregnancy were observed prospectively before and throughout their pregnancies. Thyroid function, human chorionic gonadotropin, and estradiol were measured before conception, approximately every two weeks during the first trimester, and monthly thereafter. The dose of levothyroxine was increased to maintain the thyrotropin concentration at preconception values throughout pregnancy. Twenty pregnancies occurred in 19 women and resulted in 17 full-term births. An increase in the levothyroxine dose was necessary during 17 pregnancies. The mean levothyroxine requirement increased 47 percent during the first half of pregnancy (median onset of increase, eight weeks of gestation) and plateaued by week 16. This increased dose was required until delivery. Levothyroxine requirements increase as early as the fifth week of gestation. Given the importance of maternal euthyroidism for normal fetal cognitive development, we propose that women with hypothyroidism increase their levothyroxine dose by approximately 30 percent as soon as pregnancy is confirmed. Thereafter, serum thyrotropin levels should be monitored and the levothyroxine dose adjusted accordingly. Copyright 2004 Massachusetts Medical Society
                Bookmark

                Author and article information

                Journal
                Rambam Maimonides Med J
                Rambam Maimonides Med J
                RMMJ
                Rambam Maimonides Medical Journal
                Rambam Health Care Campus
                2076-9172
                January 2016
                28 January 2016
                : 7
                : 1 , Special Issue on Differentiated Thyroid Carcinoma
                Affiliations
                Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami, Miller School of Medicine, Miami, FL, USA
                Author notes
                [* ]To whom correspondence should be addressed. E-mail: rweiss@ 123456med.miami.edu
                Article
                rmmj-7-1-e0002
                10.5041/RMMJ.10229
                4737508
                26886951
                Copyright: © 2016 Hannoush and Weiss.

                This is an open-access article. All its content, except where otherwise noted, is distributed under the terms of the Creative Commons Attribution License ( http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

                Categories
                Review
                Current Clinical Practice

                Comments

                Comment on this article