The Joint Annual Scientific Meetings of the Endocrine Society of Australia and the Society for Reproductive Biology 2018

Degraded Trabecular Bone Score is common in Young Adults with Premature Ovarian Insufficiency (#44)

Hanh H Nguyen 1 2 , Hikaru Hashimura 2 , Phillip Wong 1 2 3 , Boyd J Strauss 1 , Peter R Ebeling 1 2 , Frances Milat 1 2 3 , Amanda Vincent 2 4
  1. Department of Medicine, Monash University, Clayton, Victoria, Australia
  2. Department of Endocrinology, Monash Health, Clayton, Victoria, Australia
  3. Hudson Institute, Clayton, Victoria, Australia
  4. Monash Centre for Health Research and Implementation, Monash University, Clayton, Victoria, Australia

Background: Premature ovarian insufficiency(POI), gonadal failure ≤40 years, occurs secondary to medical(M-POI) or surgical(S-POI) therapies or is spontaneous(SP-POI). Bone loss and fractures are increased in POI. However, trabecular bone score(TBS), an indirect measure of spinal bone microarchitecture, has not been investigated in POI.

Aim: Prevalence of low BMD, degraded TBS and fractures in women with POI.

Method: Cross-sectional and longitudinal study of 70 POI women aged 20-50 years at a tertiary centre from 2005-2018. Medical history, including fracture and oestrogen replacement therapy(ERT) were obtained. Dual-energy X-ray absorptiometry(DXA) spine and femoral neck(FN) BMD and TBS(TBSiNsight v3.0.2.0) were measured. Low bone mass defined as Z-score<-2.0. Partially degraded and degraded TBS defined as TBS=1.20-1.35, and TBS<1.20, respectively. Analysis included logistic regression and linear mixed models.  

Results: Women with SP-POI (n=25), M-POI (n=16) and S-POI (n=29) were identified. Median(range) age of POI diagnosis was 33(11-40)years with baseline DXA performed median 1(0-13)year after diagnosis. ERT was used by 68.8%[lower rates in M-POI women secondary to breast cancer(p=0.001)]. Prevalence of low bone mass at the spine and FN was 8.6%: SP-POI women had lower spine BMD, FN BMD and FN Z-score than S-POI women(p<0.05). Normal, partially degraded, and degraded TBS occurred in 51.4%, 41.4%, and 7.1%, respectively, and were similar across POI groups. Longitudinal analysis of 28 POI women[median follow-up 5(1-12) years], where 15/28 had continued ERT, revealed a decline in FN BMD[-0.006g/cm2/year (95%CI -0.010, -0.002), p<0.05] but no significant change in spine BMD or TBS. Fractures occurred in 5/70(7.1%) women following POI onset, of which 4/5(80%) fractures occurred in bone with high trabecular component. No significant difference in BMD or TBS between fracture and non-fracture groups was observed.

Conclusion: Higher prevalence of abnormal TBS was observed in women with POI versus abnormal BMD Z-score. Further research is required to elucidate the role of TBS.