Thyroid function and autoimmunity are associated with the risk of vertebral fractures in postmenopausal women.

Overt or subclinical thyroid dysfunction may affect the risk of fragility fractures. The aim of the present study was to assess the association of thyroid function and autoimmunity with vertebral fractures (VF) in a large sample of Greek postmenopausal women. This cross-sectional study recruited 335 euthyroid postmenopausal women, aged 35-79 years. Euthyroidism was verified by serum thyroid-stimulating hormone (TSH) within the laboratory reference range (0.4-4.5 µIU/mL). VFs were diagnosed by lumbar spine lateral radiographs, according to quantitative procedures. Serum free triiodothyronine (FT3), free thyroxine (FT4), TSH, as well as levels of anti-thyroglobulin (anti-TG) and thyroid peroxidase antibodies (anti-TPO) were compared according to the presence of VFs. Multivariate logistic regression showed that the presence of VFs was predicted independently by ln-TSH levels (OR = 0.290, p = 0.037) and positive anti-TG antibodies (OR = 3.308, p = 0.026) in models adjusted for age, menopausal age, and ln-HOMA-IR. Stepwise logistic regression analysis showed that the presence of VFs was predicted by menopausal age (OR = 1.120, p = 0.001), ln-TSH (OR = 0.312, p = 0.052), and thyroid autoimmunity (anti-TG and anti-TPO positive: OR = 6.637, p = 0.007) in a model that also included age and ln-HOMA-IR. Women with lower circulating TSH had higher risk of having a VF, independently of age, menopausal age, and insulin resistance. The presence of positive anti-TG/anti-TPO antibodies also indicated an elevated risk of fracture. Levels of thyroid hormones had no apparent effect on the risk of fracture. Further studies are necessary to establish the significance of our findings.

Vertebral fracture prevalence among Greek healthy middle-aged postmenopausal women: association with demographics, anthropometric parameters, and bone mineral density.

BACKGROUND CONTEXT: The prevalence of skeletal fractures shows a marked geographic variability; however, data regarding the Greek population remain limited. PURPOSE: To evaluate the frequency of asymptomatic vertebral fractures (VFs), and potential risk factors, in a large sample of Greek postmenopausal women. STUDY DESIGN: A cross-sectional study at the University Menopause Clinic. PATIENT SAMPLE: Four hundred fifty-four postmenopausal women aged 35 to 80 years, with an average menopausal age of 9.2±7.1 years. OUTCOME MEASURES: They included medical history, anthropometric and biochemical parameters, bone mineral density (BMD) at lumbar spine (LS) and femoral neck (FN), and LS lateral radiographs. METHODS: Lumbar spine lateral radiographs were evaluated according to quantitative procedures, aiming to identify VFs. Anthropometric and biochemical parameters and values of BMD were compared according to the presence of VFs. RESULTS: A total of 37 (8.15%) women had at least one VF. Lumbar spine and FN-osteoporosis was identified in up to 23.1% and 40.9% subjects with prevalent VFs, respectively. The prevalence of VFs was largely associated with age, with women aged 60 years or more presenting an up to fourfold risk compared with younger women. Moreover, the presence of VFs was associated with higher menopausal age, advanced age at menarche, a history of early menopause, and prolonged lactation. Lower LS-BMD and, especially, FN-BMD were negatively associated with VF prevalence (prevalent VF vs. no VF: LS-BMD, 0.89±0.16 g/cm(2) vs. 0.98±0.16 g/cm(2), p=.010; FN-BMD, 0.72±0.10 g/cm(2) vs. 0.81±0.12 g/cm(2), p=.008). CONCLUSIONS: Asymptomatic VFs are common among Greek healthy middle-aged postmenopausal women. More than 50% subjects with prevalent VFs present with normal BMD or osteopenia. Age and bone density classification at the FN presented the strongest association with the prevalence of VFs.

Physical activity and mammographic parenchymal patterns among Greek postmenopausal women.

OBJECTIVE: To examine whether physical activity during the last five years is related to later breast mammographic density in postmenopausal Greek women. METHODS: We designed a cross-sectional study in 724 women, of ages 45-67 years. An interview-administered questionnaire was used to obtain information on duration and intensity of recreational physical activity during five years preceding study recruitment. Mammograms were evaluated according to BIRADS classification and BIRADS score was also estimated. Multivariate ordinal logistic regression analysis was used to assess associations between physical activity index and breast density according to the BIRADS classification methods. RESULTS: We observed a statistically significant inverse association of mammographic breast density measured by the BIRADS classification method and recreational exercise (OR=-0.10; 95% CI -0.018, -0.001; p=0.022). For one unit increase in physical activity as expressed by the MET-h/week score, the odds of lower versus higher breast density categories are 1.105 greater, given that all of the other variables in the model are held constant. A modifying effect by age at recruitment was evident among participants, with a stronger inverse association between recreational activity and mammographic breast density among older women (OR=-0.036; 95% CI -0.063, -0.009; p=0.009). An inverse association between physical activity and BIRADS score was evident, not reaching statistical significance (OR=0.00; 95% CI -0.009, 0.008; p=0.887). CONCLUSIONS: Mammographic breast area was lower in postmenopausal women who participated in sports/recreational physical activity compared to inactive controls. Increasing physical activity levels among postmenopausal women might be a reasonable approach to reduce mammographic density. However, until more physical activity and mammographic breast density studies are conducted that confirm our findings, they have to be interpreted with caution, due to the retrospective nature of our data and the possibility of memory bias.