Antiresorptive Therapy in Hyperthyroid Patients: Longitudinal Changes in Bone and Mineral Metabolism

Abstract

The effect of antiresorptive therapy with nasal calcitonin (CT) in recently diagnosed hyperthyroid patients on conventional medical therapy as well as the evolution of bone metabolism were assessed. Forty-five patients with recent-onset hyperthyroidism (Ͻ12 weeks) were sex and menopause stratified and randomly allocated to treatment with carbimazole (Neotomizol), carbimazole plus low dose CT (Calsynar; 100 IU/day, 2 days/week), or carbimazole plus high dose CT (Calsynar; 100 IU/day, 14 days/month). Bone mineral density was measured by dual x-ray absorptiometry in lumbar spine, femoral neck, and Ward's triangle at 0, 9, and 18 months of treatment. We also determined free T 4 , free T 3 , TSH, osteocalcin, total and bone alkaline phosphatases, tartrate-resistant acid phosphatase, type I collagen C telopeptide, and urinary hydroxyproline every 3 months of follow-up.No significant difference was observed among treatments. A euthyroid state was attained at 3 months. Bone mass increased significantly at the 9 month evaluation (P Ͻ 0.05), with a 5-10% net gain during follow-up. Nevertheless, final bone mass was 4 -8% smaller than expected. Bone formation markers were increased at 0 and 3 months, with reductions at 6 -9 months; resorption bone markers showed a significant reduction at the 3 month evaluation.These results indicate that the euthyroid state partially reduces hyperthyroidism-associated osteopenia, with a bone mass recovery period during the 6 -9 early months of effective treatment. This recovery phase is characterized by raised bone formation markers and reduced bone resorption markers. The treatment with nasal CT at the doses assayed has no additional effect over that of attainment of the euthyroid state. (J Clin Endocrinol Metab 82: 1989, 1997 P REVIOUS hyperthyroidism is a risk factor for osteoporosis (1, 2), a major public health problem. In histomorphometric studies, reconstruction of the remodeling sequence in patients with hyperthyroidism discloses a marked shortening of both the resorptive and formative phases of the remodeling cycle, with a negative balance of 9 -10 m/remodeling cycle (3). Osteoclastic and osteoblastic activities are enhanced, with a predominance of bone resorption resulting in increased levels of bone turnover markers (4) and in decreased bone mass, as determined by single photon absorptiometry (5), dual photon absorptiometry (6), and dual x-ray absorptiometry (7,8), which is the most rapid, accurate, and reproducible method to evaluate bone mineral density (BMD) (9, 10).Serum bone alkaline phosphatase determined by immunoradiometric assay (IRMA) and serum type I collagen Cterminal telopeptide (ICTP) determined by RIA have been introduced recently as formation and resorption bone turnover markers, respectively (11). These precise bone markers could clarify, in a prospective study, the existence of a bone mass recovery period after attainment of euthyroidism that has been suggested in patients treated with radioiodine (12). Moreover, recent reports have suggested the revers...

Bone mineral density, serum insulin-like growth factor I, and bone turnover markers in viral cirrhosis

“…The values were expressed as grams per square centimeter and as the z score (number of standard deviations adjusted by age and sex) in comparison with a healthy Spanish reference population (1,221 males, 1,331 females). [20][21] As previously described, 22 our laboratory in vivo (with persons) precision has a long-term coefficient of variation lower than 2% at lumbar and femoral sites of measurement. Stability of the instrument with time was checked by a daily scan of a spine phantom of known composition (Hologic).…”

Rapid Inhibition of Thyroxine-Induced Bone Resorption in the Rat by an Orally Active Vitronectin Receptor Antagonist

“…In a study that supports the effect of estradiol observed here, Franklyn et al (1995) reported that estrogen replacement therapy abolished the reduction in femoral and vertebral BMD in postmenopausal women with previous thyrotoxicosis and subsequent T4 therapy. In studies by Kung and Yeung (1996) and Jodar et al (1997), intranasal calcitonin provided no additional benefit over calcium or attainment of a euthyroid state, respectively. However, alendronate, a bisphosphonate, increased BMD Fig.…”

Marcadores séricos do metabolismo ósseo no hipertireoidismo felino

“…Estes resultados diferem dos resultados descritos em humanos, em que ocorre aumento tanto dos marcadores da formação como da reabsorção óssea (GARNERO et al, 1994;JÓDAR et al, 1997) e diminuição da massa óssea (RAISZ, 1999). Aparentemente o período experimental não foi suficiente para fazer com que os efeitos da reabsorção fossem superiores ao da formação, mesmo tendo havido diminuição da DMO, sugerindo que, nos estágios precoces, não há predomínio da atividade osteoclástica.…”

“…Só existe uma descrição da diminuição da DMO em gatos com hipertireoidismo (COSTA et al, 2006), sendo que achados semelhantes foram obtidos neste estudo. A redução significativa da DMO também foi descrita em humanos com hipertireoidismo (JÓDAR et al, 1997;KUMEDA et al, 2000), indicando perda da massa óssea (RAISZ, 1999). Este fato também foi descrito em ratos submetidos a um curto período de tireotoxicose (KUNG & NG, 1994).…”

“…A FT4 não apresentou correlação positiva com o ICTP, exceto em T2. Não foi observada correlação entre T4 e OC em um estudo realizado com 36 gatos com hipertireoidismo (ARCHER & TAYLOR, 1996), porém, a correlação entre os marcadores do metabolismo ósseo e os hormônios tireoidianos foi descrita em humanos hipertireóideos (JÓDAR et al, 1997). Isso ocorre principalmente com o ICTP, que já foi sugerido como bom marcador indireto da avaliação do status da glândula tireóide.…”