Body composition, bone mineral density and fractures in late postmenopausal women with polycystic ovary syndrome – a long‐term follow‐up study

Abstract

Hyperandrogenism is one of the characteristic features of the polycystic ovary syndrome (PCOS). Androgens are important for bone mass. Studies on bone mineral density (BMD) and fractures in postmenopausal women with PCOS are lacking. The aim of this study was to investigate whether postmenopausal women with PCOS differ from controls regarding body composition, BMD and prevalence of fractures, and to compare women with PCOS with controls regarding correlations between total BMD and sex hormones. A prospective 21-year follow-up study. Anthropometry, hormonal measurements and questionnaires were performed in 1987 and in 2008. Fractures were X-ray-verified. BMD measurements were taken in 1992, using single-photon absorptiometry (SPA), and in 2008, using dual-energy X-ray absorptiometry (DXA), to also enable measurements of body composition. Twenty-five women with PCOS (Rotterdam criteria), aged 61-78 years, and 68 randomly allocated age-matched controls. Body composition, BMD, fractures and sex steroids. At follow-up, the postmenopausal women with PCOS maintained a higher free androgen index (FAI), but had similar body fat, lean mass and BMD compared with controls. The hip circumference increased only in women with PCOS (P < 0·01), during follow-up. The fracture incidence was similar to that of controls (56% vs 41%, ns). In the controls, total BMD was positively correlated with oestradiol (R = 0·322, P < 0·01) and FAI (R = 0·307, P < 0·05) and negatively correlated with SHBG (R = -0·429, P < 0·001), but not in the women with PCOS. Postmenopausal women with PCOS with persistently higher FAI had similar muscle mass, BMD and fracture incidence as controls during this long-term follow-up.