In pre- and early perimenopausal women, prediabetes (with blood glucose ≥ 110 mg/dL) and greater insulin resistance are associated with worse trabecular bone quality (as assessed by trabecular bone score).

Purpose

Diabetes mellitus (DM) is associated with lower trabecular bone score (TBS) and fracture; less certain is whether the precursor states of prediabetes and increased insulin resistance are also related to adverse bone outcomes. We examined, in women who do not have DM, the associations of glycemic status (prediabetes vs. normal) and insulin resistance with TBS.

Methods

This was a cross-sectional analysis of baseline data collected from 42- to 52-year-old, pre- and perimenopausal participants in the Study of Women's Health Across the Nation (SWAN) TBS Study. Women with prediabetes were categorized as having either high prediabetes if their fasting glucose was between 110 and 125 mg/dL or low prediabetes if their fasting glucose was between 100 and 109 mg/dL. Normoglycemia was defined as a fasting glucose below 100 mg/dL.

Results

In multivariable linear regression, adjusted for age, race/ethnicity, menopause transition stage, cigarette use, calcium and vitamin D supplementation, lumbar spine bone mineral density, and study site, women with high prediabetes had 0.21 (p < 0.0001) standard deviations (SD) lower TBS than those with normoglycemia. Low prediabetes was not associated with lower TBS. When HOMA-IR levels were ≥ 1.62, each doubling of HOMA-IR was associated with a 0.11 SD decrement in TBS (p = 0.0001).

Conclusion

Similar to diabetics, high prediabetics have lower TBS than normoglycemic individuals. Women with greater insulin resistance have lower TBS even in the absence of DM. Future studies should examine the associations of high prediabetes and insulin resistance with incident fracture.

Proton pump inhibitors (PPIs) have been associated with diminished bone mineral density (BMD) and an increased risk of fracture; however, prior studies have not yielded consistent results, and many have suboptimal ascertainment of both PPI use and BMD. We used data from the Study of Women's Health Across the Nation (SWAN), a multicenter, multi-ethnic, community-based longitudinal cohort study of women across the menopause transition to examine the association between annualized BMD changes and new use of PPIs. We compared changes in BMD in new PPI users with changes in BMD in new users of histamine 2 receptor antagonists (H2RAs) and with changes in BMD in subjects who did not use either class of medications. Mixed linear regression models included recognized risk factors for osteoporosis, including demographics, menopausal transition stage, body mass index (BMI), lifestyle factors, as well as comorbidities and concomitant medications. To provide further evidence for the validity of our analytic approach, we also examined the effects of hormone-replacement therapy (HT), a class of medications that should reduce bone loss, on changes in BMD as an internal positive control group. We identified 207 new users of PPIs, 185 new users of H2RAs, and 1,676 non-users. Study subjects had a mean age of 50 years and were followed for a median of 9.9 years. Adjusted models found no difference in the annualized BMD change at the lumbar spine, femoral neck, or total hip in PPI users compared with H2RA users or non-users. These results were robust to sensitivity analyses. BMD increased as expected in HT users, supporting the validity of our study design. These longitudinal analyses plus similar prior studies argue against an association between PPI use and BMD loss.