{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/73000"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/73000","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"An Evaluation of 1) Bone Changes Following Bariatric Surgery and 2) Fat and Muscle Indices Assessed by pQCT: Implications for Osteoporosis and Type-2 Diabetes Risk","abstract":"STUDY 1 Aim: To compare the effects of Roux-en-Y gastric bypass (RYGB) and laparoscopic adjustable gastric banding (LAGB) on changes in bone mineral density (BMD), weight loss and blood biomarkers related to bone turnover, hormonal, and nutrient status. Subjects: Nine bariatric surgery patients. Methods: Patients had a DXA bone scan and fasting blood draw at baseline, three, and six months following surgery. Results: RYGB patients had greater weight loss vs. LAGB at both three (mean loss: 19 vs. 9%) and six months (26 vs. 11%), p<0.01. RYGB patients lost an average of 7% hip BMD at six months. Hip BMD loss at six months was correlated to decreased leptin (r=0.88) and increased adiponectin (r=-0.82), p<0.05. Bone turnover was indicated by elevated serum bone biomarkers after surgery. Conclusions: Research with larger sample sizes is warranted to better evaluate potential implications for late-life osteoporosis risk following bariatric surgery. STUDY 2 Aim: To determine repeatability for IMAT and muscle density, to evaluate the distribution of foreleg muscle and fat indices measured by pQCT and to determine predictors of muscle density and type-2 diabetes risk. Subjects: 82 women with varying BMI and physical activity levels. Methods: Subjects had DXA and pQCT bone scans, a fasting blood draw, and completed a 4-day physical activity record. Results: Fat and muscle distribution in the foreleg was highly correlated to total and central body adiposity. The pQCT device reliably measured muscle density (CV=0.8%), thus justifying use as surrogates for IMAT. Muscle density was positively related to physical activity (r=0.29; p<0.05) and negatively associated with markers of fat distribution and risk for type-2 diabetes [HOMA-IR (r=-0.44, p<0.01)]. Conclusions: Further research is necessary to determine whether specific fat or muscle depots can be targeted through exercise training to help with the prevention and treatment of obesity or type-2 diabetes.","abstract_html":"STUDY 1 Aim: To compare the effects of Roux-en-Y gastric bypass (RYGB) and laparoscopic adjustable gastric banding (LAGB) on changes in bone mineral density (BMD), weight loss and blood biomarkers related to bone turnover, hormonal, and nutrient status. Subjects: Nine bariatric surgery patients. Methods: Patients had a DXA bone scan and fasting blood draw at baseline, three, and six months following surgery. Results: RYGB patients had greater weight loss vs. LAGB at both three (mean loss: 19 vs. 9%) and six months (26 vs. 11%), p&lt;0.01. RYGB patients lost an average of 7% hip BMD at six months. Hip BMD loss at six months was correlated to decreased leptin (r=0.88) and increased adiponectin (r=-0.82), p&lt;0.05. Bone turnover was indicated by elevated serum bone biomarkers after surgery. Conclusions: Research with larger sample sizes is warranted to better evaluate potential implications for late-life osteoporosis risk following bariatric surgery. STUDY 2 Aim: To determine repeatability for IMAT and muscle density, to evaluate the distribution of foreleg muscle and fat indices measured by pQCT and to determine predictors of muscle density and type-2 diabetes risk. Subjects: 82 women with varying BMI and physical activity levels. Methods: Subjects had DXA and pQCT bone scans, a fasting blood draw, and completed a 4-day physical activity record. Results: Fat and muscle distribution in the foreleg was highly correlated to total and central body adiposity. The pQCT device reliably measured muscle density (CV=0.8%), thus justifying use as surrogates for IMAT. Muscle density was positively related to physical activity (r=0.29; p&lt;0.05) and negatively associated with markers of fat distribution and risk for type-2 diabetes [HOMA-IR (r=-0.44, p&lt;0.01)]. Conclusions: Further research is necessary to determine whether specific fat or muscle depots can be targeted through exercise training to help with the prevention and treatment of obesity or type-2 diabetes.","abstract_has_math":false,"creators":["Butner, Katrina Lindauer"],"institution":"Virginia Tech","degree_name":"Ph. D.","degree_level":"doctoral","degree_discipline":"Human Nutrition, Foods, and Exercise","degree_department":"Human Nutrition, Foods, and Exercise","school":null,"contributors":[],"advisors":[],"committee_chairs":["Herbert, William G."],"committee_members":["Clark, Susan F.","Nickols-Richardson, Sharon M.","Ramp, Warren K."],"year":2010,"date_issued":"2010-10-29","date_published":"2010-10-29","updated_at":"2026-07-22T22:19:56Z","subjects":["Bone Mineral Density","Study 2: Intermuscular Adipo","Physical Activity","Bariatric Surgery","Type-2 Diabetes"],"languages":["en_US"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-11092010-173306"],"render_values":[{"text":"etd-11092010-173306","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/73000","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Herbert, William G."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Clark, Susan F.","Nickols-Richardson, Sharon M.","Ramp, Warren K."]},{"key":"dc:contributor.department","label":"Department","values":["Human Nutrition, Foods, and Exercise"]},{"key":"dc:creator","label":"Author","values":["Butner, Katrina Lindauer"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2016-09-22T15:14:42Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2016-09-22T15:14:42Z","2015-04-22"]},{"key":"dc:date.issued","label":"Date","values":["2010-10-29"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Human Nutrition, Foods, and Exercise"]},{"key":"thesis:degree_level","label":"Degree Level","values":["doctoral"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph. D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Bone Mineral Density","Study 2: Intermuscular Adipo","Physical Activity","Bariatric Surgery","Type-2 Diabetes"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-11092010-173306"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/73000"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["STUDY 1 Aim: To compare the effects of Roux-en-Y gastric bypass (RYGB) and laparoscopic adjustable gastric banding (LAGB) on changes in bone mineral density (BMD), weight loss and blood biomarkers related to bone turnover, hormonal, and nutrient status. Subjects: Nine bariatric surgery patients. Methods: Patients had a DXA bone scan and fasting blood draw at baseline, three, and six months following surgery. Results: RYGB patients had greater weight loss vs. LAGB at both three (mean loss: 19 vs. 9%) and six months (26 vs. 11%), p<0.01. RYGB patients lost an average of 7% hip BMD at six months. Hip BMD loss at six months was correlated to decreased leptin (r=0.88) and increased adiponectin (r=-0.82), p<0.05. Bone turnover was indicated by elevated serum bone biomarkers after surgery. Conclusions: Research with larger sample sizes is warranted to better evaluate potential implications for late-life osteoporosis risk following bariatric surgery. STUDY 2 Aim: To determine repeatability for IMAT and muscle density, to evaluate the distribution of foreleg muscle and fat indices measured by pQCT and to determine predictors of muscle density and type-2 diabetes risk. Subjects: 82 women with varying BMI and physical activity levels. Methods: Subjects had DXA and pQCT bone scans, a fasting blood draw, and completed a 4-day physical activity record. Results: Fat and muscle distribution in the foreleg was highly correlated to total and central body adiposity. The pQCT device reliably measured muscle density (CV=0.8%), thus justifying use as surrogates for IMAT. Muscle density was positively related to physical activity (r=0.29; p<0.05) and negatively associated with markers of fat distribution and risk for type-2 diabetes [HOMA-IR (r=-0.44, p<0.01)]. Conclusions: Further research is necessary to determine whether specific fat or muscle depots can be targeted through exercise training to help with the prevention and treatment of obesity or type-2 diabetes."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Ph. D."]},{"key":"dc:title","label":"Title","values":["An Evaluation of 1) Bone Changes Following Bariatric Surgery and 2) Fat and Muscle Indices Assessed by pQCT: Implications for Osteoporosis and Type-2 Diabetes Risk"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Herbert, William G."],"dc:contributor.committeemember":["Clark, Susan F.","Nickols-Richardson, Sharon M.","Ramp, Warren K."],"dc:contributor.department":["Human Nutrition, Foods, and Exercise"],"dc:creator":["Butner, Katrina Lindauer"],"dc:date.accessioned":["2016-09-22T15:14:42Z"],"dc:date.available":["2016-09-22T15:14:42Z","2015-04-22"],"dc:date.issued":["2010-10-29"],"dc:description.abstract":["STUDY 1 Aim: To compare the effects of Roux-en-Y gastric bypass (RYGB) and laparoscopic adjustable gastric banding (LAGB) on changes in bone mineral density (BMD), weight loss and blood biomarkers related to bone turnover, hormonal, and nutrient status. Subjects: Nine bariatric surgery patients. Methods: Patients had a DXA bone scan and fasting blood draw at baseline, three, and six months following surgery. Results: RYGB patients had greater weight loss vs. LAGB at both three (mean loss: 19 vs. 9%) and six months (26 vs. 11%), p<0.01. RYGB patients lost an average of 7% hip BMD at six months. Hip BMD loss at six months was correlated to decreased leptin (r=0.88) and increased adiponectin (r=-0.82), p<0.05. Bone turnover was indicated by elevated serum bone biomarkers after surgery. Conclusions: Research with larger sample sizes is warranted to better evaluate potential implications for late-life osteoporosis risk following bariatric surgery. STUDY 2 Aim: To determine repeatability for IMAT and muscle density, to evaluate the distribution of foreleg muscle and fat indices measured by pQCT and to determine predictors of muscle density and type-2 diabetes risk. Subjects: 82 women with varying BMI and physical activity levels. Methods: Subjects had DXA and pQCT bone scans, a fasting blood draw, and completed a 4-day physical activity record. Results: Fat and muscle distribution in the foreleg was highly correlated to total and central body adiposity. The pQCT device reliably measured muscle density (CV=0.8%), thus justifying use as surrogates for IMAT. Muscle density was positively related to physical activity (r=0.29; p<0.05) and negatively associated with markers of fat distribution and risk for type-2 diabetes [HOMA-IR (r=-0.44, p<0.01)]. Conclusions: Further research is necessary to determine whether specific fat or muscle depots can be targeted through exercise training to help with the prevention and treatment of obesity or type-2 diabetes."],"dc:description.degree":["Ph. D."],"dc:identifier.other":["etd-11092010-173306"],"dc:identifier.uri":["http://hdl.handle.net/10919/73000"],"dc:language.iso":["en_US"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["Bone Mineral Density","Study 2: Intermuscular Adipo","Physical Activity","Bariatric Surgery","Type-2 Diabetes"],"dc:title":["An Evaluation of 1) Bone Changes Following Bariatric Surgery and 2) Fat and Muscle Indices Assessed by pQCT: Implications for Osteoporosis and Type-2 Diabetes Risk"],"dc:type":["Dissertation"],"dc:type.dcmitype":["Text"],"thesis:degree_discipline":["Human Nutrition, Foods, and Exercise"],"thesis:degree_level":["doctoral"],"thesis:degree_name":["Ph. D."],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:56Z"}