Spinal bone mass after long-term treatment with L-Thyroxine in postmenopausal women with thyroid cancer and chronic lymphocytic thyroiditis

Abstract

This study investigated the effect of long-term treatment upon bone density with L-Thyroxine in postmenopausal women compared with untreated postmenopausal women with climacteric symptoms. We measured spinal bone density in three groups (n = 84) of postmenopausal women: (A) those treated with TSH-suppressive doses of L-Thyroxine for a medium of 5 years after removal of thyroid cancer; (B) those on L-Thyroxine treatment for a median of 9 years after being diagnosed with chronic lymphocytic thyroiditis (CLT); and (C) those with no thyroid disease or other known pathology and without any treatment. There were no differences in dietary calcium intake and daily activity between untreated and L-Thyroxine-treated women. Measurements of bone mineral density were performed at spine level L1-L4 using a dual X-ray densitometer and serum thyroid-stimulating hormone (TSH), thyroid hormones, and bone markers (serum osteocalcin, procollagen I, urinary calcium), and PTH levels were assayed and found to be within normal ranges. Women receiving L-Thyroxine after thyroid cancer had slightly higher FT4 levels compared with women who had CLT and lower TSH levels, with serum T4 and T3 levels normal and similar in both groups. No significant differences were found in spinal bone density after L-Thyroxine treatment between Groups A and B and compared with Group C. Bone loss according to 2 SD below reference standards (age and sex matched) was found in the 12.9% of L-Thyroxine-treated patients versus 22.6% of untreated women. No correlation was found between bone loss and thyroid hormone levels and duration of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Changes in Pre- and Postmenopausal Women with Thyroid Cancer on Levothyroxine Therapy: Evolution of Axial and Appendicular Bone Mass

“…Previous studies have reported conflicting results, bone loss being described as minimal [18,19], significant [8,11,12,[20][21][22][23] or absent [9,10,24]. The same is valid for the preferential localization of the bone loss, mainly lumbar [20,23,25], femoral [11,21] or appendicular [8], and also for the influence of menopause [9,11,26].…”

“…Nevertheless, the effect of prolonged subclinical hyperthyroidism on bone mass is controversial [5][6][7]. Cross-sectional studies of bone density in patients on levothyroxine (LT 4 ) suppressive therapy yielded discordant results ranging from unchanged bone mass [8][9][10] to 20-23% reductions in axial and appendicular bone mass [11,12]. Confounding variables such as parathyroid and menopausal status, and also prior history of hyperthyroidism, may be responsible for such differences.…”

Lack of deleterious effect on bone mineral density of long-term thyroxine suppressive therapy for differentiated thyroid carcinoma

“…With respect to hyperthyroidism due to suppressive LT4 treatment, some trials included premenopausal women with little or no change in BMD between controls and long-term treated patients (Franklyn et al 1992, Giannini et al 1994, Marcocci et al 1994, Muller et al 1995. Studies performed in postmenopausal women showed decreased BMD in all measured sites in two trials (Diamon et al 1991, Kung & Yeung 1996 and no changes in another six (Franklyn et al 1992, Giannini , Hawkins et al 1994, Marcocci et al 1994, Muller et al 1995, Go¨rres et al 1996, Guo et al 1997.…”

The effect of long-term, non-suppressive levothyroxine treatment on quantitative ultrasonometry of bone in women

“…Some reports, including a meta-analysis by Wü ster (9), have suggested that the bone mineral density (BMD) is reduced in patients taking long-term treatment to suppress thyroid stimulating hormone (TSH) (levothyroxine, L-T 4 ) compared with controls (10-13). However, other studies have failed to confirm this decremental effect of L-T 4 treatment on BMD (14)(15)(16)(17) or on the prevalence of fracture (18,19). L-T 4 treatment that does not suppress TSH seems to have little effect on bone (20)(21)(22)(23).…”