Background
Low bone density (BMD) and fractures commonly affects women with premature ovarian insufficiency (POI). However, bone microarchitecture and body composition data are lacking.
Objective
Assess skeletal and soft tissue variables, fracture prevalence and oestrogen replacement therapy (ERT) effects in POI women.
Method
Cross-sectional and longitudinal studies of 60 normal karyotype POI women, aged 20-40 years, from 2005-2018. Dual x-ray absorptiometry (DXA)-derived spinal (LS) and femoral neck (FN) BMD, trabecular bone score (TBS), total lean mass (TLM), total fat mass (TFM), and fracture prevalence were compared with 60 age-, sex- and BMI-matched population-based controls. Longitudinal changes in bone and body composition variables, and ERT effects were analysed using linear mixed models.
Results
POI participants were subdivided into spontaneous (s)-POI (n=25) and iatrogenic (i)-POI (n=35). Median (range) age of POI diagnosis was 34 (10-40) years with baseline DXA performed at median 1(0-13) year post-diagnosis. ERT was used by 81.5 % (similar for both groups). LS- and FN-BMD were lowest in s-POI (p<0.05). Low TBS (including both partially degraded and degraded TBS) 1 was more common in s-POI [(44%), p=0.031], versus other groups. TLM was lower in both s-POI and i-POI groups than controls (p=0.001). Fracture prevalence was not significantly different: 20%(s-POI), 17% (i-POI), and 8% (controls) (p=0.196). Longitudinal analysis of 24 POI women showed continuous ERT was associated with TLM increment of 256.5g/year (p<0.001) and protected against BMD loss. However, ERT interruption was associated with annual reductions in FN BMD and TBS of 0.020g/cm2 and 0.007 (p<0.05), respectively.
Conclusion
Deficits in BMD, trabecular microarchitecture, and lean mass were present in women with POI. However, continuous ERT protected against declines in these variables, with an increase in TLM. Assessment of skeletal and muscle health, and advocating continuous ERT, is essential in POI women to optimise musculoskeletal outcomes.