Deriving Bone Density from Thoracic CT Scans, STTR Phase II

ABSTRACT Osteoporosis is a major cause of disability and morbidity in our populationAs many asmillion Americans have osteoporosis andmillion more have osteopeniaHoweverbone mineral densityBMDassessment does not occur in many Americans when indicated and measure currently requires a separate referral and separate imaging scan to obtain BMDThe result is that onlyof Americans who are at risk of suffering a hip fracture get BMD assessment and this problem is most likely heightened in ethnic racial subgroupsPreventive measurese gdrugs to inhibit bone losscannot be administered in the absence of measurement of BMDWe have createdpatented and published a quantitative technique to measure BMD from the thoracic spine using chest CT scans without need of calcium phantom under the patienteffectively opening this up to every chest CT both prospectively and previously acquiredWe have validated our method in multiple cohorts with cardiac CT scansbut have not achieved sufficient evaluation to sway guidelines and recommendations for preferred use of DXA scanningThis will require evaluation in epidemiologic studies and outcomes that show CT BMD can predict fracturesCT imaging is very common in persons who meet criteria for osteoporosis screeningand these patients have multiple co morbidities that may be associated with increased bone riskEffective strategies to prevent bone loss and or to treat osteoporosis include calcium and vitamin Dhormone replacement when indicatedcalcitoninand bisphosphonate administrationHowevermany patients remain undiagnosed until their first fracture because of the lack of recognition of the diseaseWith an increased awareness by endocrinologistsrheumatologists and primary care physiciansthe increased use of preventive strategiesthe impact of osteoporosis and subsequent hip fractures on those patients should decreaseThis use of CT is not fully validated as we have not established the prevalence of the disease with our methods using CT scans in epidemiologic populationsor that low CT BMD correlates with fractures in this populationWe have a cohort ofadults who underwent serial CT imagingtimes overyears in the Multi Ethnic Study of AtherosclerosisMESAOur QCT method will be applied to all visible thoracic levelsWe therefore plan toutilize thechest CT scans already performed in MESAdevelop prevalence of osteopeniaosteoporosis and vertebral fracturesdetermine the association between low CT BMD and presence and incidence of fractures in the DM populationwith follow up approachingyears in this populationMeasuring BMD on chest CT scans will identify whether they have an increased prevalence of osteoporosis and osteopeniato justify assessing BMD testing when they undergo CT scansThis can simplify and streamline health care screening by assessing two diseasesBMD and CAD or lung cancerin one testalready acquired clinically in millions of patientsallowing cost effective osteoporosis diagnosis PROJECT NARRATIVE This study proposes to evaluate bone density from CT scans acquired during the Multi Ethnic Study of Atherosclerosis usingcomputed tomography scans acquired overyears inpeopleThis study will allow us toidentify true prevalencein a contemporary cohortof osteopenia and osteoporosis in different race ethnic and gender subgroupswithout requiring a bone density phantom underneath the patientvalidating CT BMD ability to predict incident fractures andallow serial measures of CT BMD by evaluating the ability to identify changes in BMD over time and evaluate for incident osteopenia and osteoporosisInsert Running title of andltcharacters