Relationship between bone mineral density and insulin resistance in polycystic ovary syndrome.
ABSTRACT The aim of the present study was to evaluate whether there is a relationship between bone mineral density (BMD) and insulin resistance and hyperinsulinemia in women with polycystic ovary syndrome (PCOS). The study consisted of 28 amenorrheic women with PCOS and 11 amenorrheic women without PCOS. Fifteen healthy women with normal ovulatory function, matched for age and body mass index (BMI), served as controls. BMD was measured at the lumbar spine and left femoral neck with dual-energy X-ray absorptiometry. Blood samples were obtained to measure serum levels of insulin, follicle-stimulating hormone, luteinizing hormone, sex hormone-binding globulin (SHBG), total and free testosterone, androstenedione and estradiol by radioimmunassay. Insulin resistance was estimated by the in sulin tolerance test (ITT), and K(ITT) was taken as the insulin sensitivity index. In the PCOS group, K(ITT) was significantly lower and insulin levels were higher than in either of the control groups (P < 0.001). BMD in the PCOS group was lower than in the healthy group and higher than in the amenorrheic control group (P < 0.05). In the PCOS group, there were positive correlations of BMD of the lumbar spine with insulin (r = 0.42: P < 0.05) and negative correlations of BMD with K(ITT) (r = -0.58; P < 0.001) and SHBG (r = -0.38; P < 0.05). The inverse association of BMD and K(ITT) was independent of BMI, insulin, SHBG, androstenedione, and free testosterone. In conclusion, insulin resistance and hyperinsulinemia in women with PCOS may be a relative protective factor against bone mineral loss.
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ABSTRACT: The mechanisms leading to higher bone mineral density (BMD) in hirsute patients than in healthy controls have seldom been examined. We compared the metabolic, hormonal and bone metabolic parameters in hirsute patients and female controls and correlated BMD and bone metabolic parameters with testosterone, oestradiol and metabolic parameters. Fifty-one Caucasian, reproductive-aged, hirsute patients referred to the outpatient clinic of an academic tertiary-care medical centre and 63 healthy, female Caucasian controls matched for season, weight and age. BMD (hip, neck, lumbar and total BMD), bone metabolic parameters (osteocalcin, alkaline phosphatase, PTH, ionized calcium, phosphate and 25-hydroxyvitamin D (25OHD)) and endocrine profiles (androgen status, oestradiol and insulin) were evaluated during follicular phase. Oestradiol measurement was repeated during cycle days 8-12. Lumbar and neck BMD levels were significantly higher in hirsute patients than in controls: (mean +/- SD): lumbar BMD 1.10 +/- 0.12 vs. 1.06 +/- 0.10 g/cm2 and neck BMD 0.91 +/- 0.11 vs. 0.87 +/- 0.12 g/cm2, P < 0.05. Fasting insulin and free testosterone levels were significantly higher in hirsute patients than in controls. Free testosterone correlated positively with neck and hip BMD levels in hirsute patients. During multiple regression analysis, testosterone, oestradiol and waist/hip ratio (WHR) were found to have positive effects on BMD levels independent of body mass index (BMI). 25OHD levels were significantly lower in hirsute patients [42 (13-131)] than in controls [72 (27-196)] nmol/l (geometric mean +/- 2SD), P < 0.001]. Hirsute patients demonstrated significantly higher bone mineral density levels than controls, which could be explained by hyperinsulinaemia and higher testosterone levels in hirsute patients compared with controls. The pathogenesis for significantly lower 25-hydroxyvitamin D levels in hirsute patients compared with controls needs to be evaluated in future studies.Clinical Endocrinology 07/2005; 62(6):683-91. · 3.40 Impact Factor
Article: Treatment of PCOS in adolescence.[show abstract] [hide abstract]
ABSTRACT: Polycystic ovary syndrome (PCOS) is increasingly being recognized in adolescent girls seeking treatment for signs and symptoms of hyperandrogenism. It is difficult to diagnose PCOS in adolescents, therefore a high index of suspicion is necessary. Timely screening and treatment are crucial because another important component of the syndrome is insulin resistance/hyperinsulinemia increasing the risk for type 2 diabetes, dyslipidemia, and cardiovascular sequelae. Diagnosis of PCOS in adolescents should include a thorough family history, exclusion of other causes of hyperandrogenism, and appropriate laboratory evaluation. The scarcity of controlled clinical trials makes treatment controversial. Therapeutic options include lifestyle intervention, oral contraceptive pills, and insulin sensitizers. Long-term follow-up is needed to determine the effectiveness of these approaches in changing the natural history of the reproductive and metabolic outcomes without causing undue harm.Bailliè re s Best Practice and Research in Clinical Endocrinology and Metabolism 07/2006; 20(2):311-30. · 4.91 Impact Factor
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ABSTRACT: Women with polycystic ovary syndrome (PCOS) may have increased cortical bone mineral density (BMD) and probably higher bone material quality as well as better resistance in the compression strength of the tibia, measured by peripheral quantitative computed tomography (pQCT), in comparison with that of age-matched healthy subjects. Thirty women with PCOS, (15 lean and 15 obese) and 15 age-matched healthy controls were enrolled in this study. The clinical, biochemical and ultrasound characteristics of the two groups were evaluated. Using pQCT, the following parameters were measured: volumetric cortical density (CBD) and volumetric trabecular density (TBD) BMD, total bone cross-sectional area (ToA), cortical area (CoA), cortical thickness (CRT-THK-C) and finally the strength-strain index (SSI). The geometrical parameters (CoA, ToA, CRT-THK-C), the SSI as well as the TBD were increased in the PCOS women; however, these differences did not achieve statistical significance between lean PCOS women, obese PCOS women, and controls. Conversely, CBD was significantly higher in PCOS women compared with controls (P < 0.000) and furthermore in lean PCOS women compared with obese ones (P < 0.01040). The PCOS women of our study seem to have a higher quality of bone material in the distal tibia and probably a better resistance of bone in the compression strength without alterations in bone mass and geometry (especially the lean PCOS women), indicating that our oligomenorrheic and hyperandrogonemic PCOS women may be protected from the development of osteoporosis and fracture risk later in life.Human Reproduction 08/2010; 25(8):2107-14. · 4.67 Impact Factor