Bone material strength in normoglycemic and hyperglycemic adults



 DESCRIPTION (provided by applicant): Fractures of the hip and other sites are increased nearly two-fold in patients with type 2 diabetes despite their having higher bone mineral density (BMD) than others. This suggests that bone qualities other than BMD, including bone material strength (BMS) and trabecular bone score (TBS), are compromised in diabetes. Most measurements of bone strength are expensive and impractical for use in health care settings or in large clinical trials. It is therefore important to identify more practical methods that can be used to investigate the effects of hyperglycemia on skeletal health and how interventions may improve skeletal health in diabetes. The proposed project evaluates recently developed measures of bone quality, BMS and TBS, as they relate to glycemia. The ability to use straightforward clinical tests to identify individuals who may be at risk for diabetic skeletal fragility would address a critical barrier in the field and would have major impact on clinical management of skeletal fragility associated with diabetes. The overall goal of the proposed project is to obtain preliminary information about BMS and TBS as potential clinical indicators of fracture risk among individuals with prediabetes and diabetes and as potential outcome measures in future clinical trials of diabetes interventions. Information gained from the proposed study is expected to justify and facilitate the inclusion of two low cost, minimally invasive measures of bone quality as primary or secondary measures in intervention studies designed to prevent and treat type two diabetes and its sequelae including fractures. The proposed cross-sectional study investigates associations of glycemia and other subject characteristics with BMS and TBS in 200 adults (age 50+) with normoglycemia, prediabetes and untreated diabetes. BMS measurement of the non-dominant anterior mid-tibia will be measured with a minimally invasive handheld instrument. TBS will be derived from spine DXA scan images. Other measurements include bone density scans of the same mid-tibial site and other skeletal sites, as well as other physical measurements and medical and lifestyle information obtained by questionnaire. One fasting blood sample will be analyzed for HbA1c, plasma glucose, serum creatinine and 25- hydroxyvitamin D, and urinary pentosidine. Analyses will examine associations of glycemic status, physical and lifestyle characteristics with BMS and TBS and will examine differences in these measures across demographic categories and diabetes status groups.