Abstract: MON 223
Biochemically euthyroid patients with symptoms attributable to thyroid disease, have a high prevalence of abnormal bone mineral density and fractures in both genders.
Presenter: Georgia Antoniou
Background: Patients with symptoms indicative of thyroid dysfunction, and normal thyroid hormones, were found to harbor thyroid function abnormalities (1). Since thyroid function is closely related to skeletal homeostasis, we designed the present study to evaluate this population with regard to bone metabolism.view more
Background: Patients with symptoms indicative of thyroid dysfunction, and normal thyroid hormones, were found to harbor thyroid function abnormalities (1). Since thyroid function is closely related to skeletal homeostasis, we designed the present study to evaluate this population with regard to bone metabolism.
Methods: We prospectively enrolled subjects at our Endocrinology Practice in Patras, Greece, between 2014-2016. Subjects presenting with multiple, otherwise unexplained symptoms of potential thyroid dysfunction, such as palpitations, diaphoresis, anxiety, sleep disorders, hair loss, brittle nails, eyebrows thinning, constipation and weight changes were included in the study. We measured serum TSH, total and free-T3, total and free T4, 25-OH-D, PTH, calcium, albumin, phosphate, blood urea nitrogen, creatinine; we performed bone mineral density (BMD) measurement with dual-energy X-ray absorptiometry (DEXA) scan, thyroid ultrasound with estimation of thyroid vascularity and Tc-99m scan. We collected data on fractures history, nephrolithiasis and family history of osteoporosis or thyroid disease. We excluded subjects with primary hyperparathyroidism, abnormal thyroid hormones and those taking medications potentially affecting thyroid hormone measurements. We split our subjects’ BMD, based on the lowest T- or Z-score in “Normal” (>-1.0), “low bone mass” (LBM) (<-1.0, >-2.5) and “Osteoporosis” (<-2.4). Odds ratios were calculated with Fischer's exact test, while continuous variables means were compared with one-way ANOVA.
Results: We screened 2624 subjects; 323 (90 males and 233 females) met the inclusion criteria. Βone density was abnormal in 66% of the cohort; LBM was present in 46% and osteoporosis in 20% of the subjects. Abnormal bone density was present equally in both sexes (69.7% of males and 65.3% of females, OR 1.24, p>0.05). Advancing age was associated with increasing rates of osteoporosis in females (p<0.0001), but not males (p>0.05). Males had higher osteoporosis risk in the younger age group (<50 years) compared to females (22.7% vs. 4.8% OR 7.44, p=0.003). This difference was not significant in the older age group (19.0% vs. 29.7%, OR 0.58, p>0.05). Males had higher fracture rates overall (20.0% vs. 10.7%, OR-2.08, p=0.043).
Conclusions: Patients with symptoms suggestive of thyroid dysfunction and normal thyroid hormones, exhibit a marked tendency towards low bone mass and fractures, with males affected at a younger age. Therefore, this population might suffer of a previously unrecognized, preclinical thyroid disease, with features similar to thyroid overactivity with regard to bone metabolism.
(1) Chourpiliadis Ch, Bantouna D and Paparodis RD. 2016 Screening for Primary Thyroid Disorders with Serum TSH Measurement Alone, Might be Inadequate, Poster presented at the 98th Annual Meeting of the Endocrine Society, April 1, 2016, Boston, MA.