Osteoporosis is emerging as an important public health problem at an enormous cost to the National Health Service. This thesis observes the effects of certain states of hypo-oestrogenism, seen naturally during breast feeding and after the menopause, and the pathological states seen in hyperprolactinaemia and hypogonadotrophic amenorrhoea. It also observes the drug-induced situation resulting from the use of the gonadotrophin-releasing hormone analogue, goserelin. Bone density was measured using dual-energy X-ray absorptiometry (DEXA). This is very acceptable to subjects since the radiation dose is small and the low reproducibility makes short term longitudinal study possible. A biochemical assessment was also made measuring plasma osteocalcin and the cross-links pyridinoline and deoxypyridinoline excreted in the urine. In the group of early menopausal women we were unable to predict absolute BMD at either lumbar spine or femoral neck from personal risk factors. Body weight was the strongest predictor of bone density at each site. Rates of bone loss were greatest in the smokers and in those closest to their last menstrual period. The biochemical assessment was unhelpful. Those women with hypogonadotrophic hypogonadism had significantly lower bone density than age-matched normals. These were mainly young women with weight loss-related amenorrhoea. Those women with hyperprolactinaemia had a very normal bone density. In both groups no change in bone density was seen over the study period. The greatest reductions in bone density were seen in the breast feeding women and in those receiving treatment with the GnRH analogue, goserelin. In summary, the observed situations have resulted in changes in bone density. The magnitude of these changes are small and it is not clear how these small changes influence clinical outcome.

Thesis (M. Nurs.)--University of Hong Kong, 2007.

Thesis (M. Med. Sc.)--University of Hong Kong, 2004. / Also available in print.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Submitted to the faculty of the University Graduate School in partial fulfillment of the requirements for the degree Master of Sciences in the School of Informatics, Indiana University, August 2004 / Osteoporosis is the most common bone disease in United States and developed countries and a major public health threat for an estimated 44 million Americans. It is characterized by low bone mineral density and micro architectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture, especially of hip, spine and wrist. Osteoporosis is multifactorial disease influenced by large number of environmental and genetic factors. Though a number of FDA approved drugs are available for treating this complex disease, a medication, which could specifically and effectively reverse symptoms of it is lackin. As the initial step for approaching disease treatment my current research focuses on locatin candidate genes on linkage regions for BMD on human chromosomes, which potentially can be used for developing novel targets and strategies for therapeutic interventions. We will also define the mouse homologs in the syntenic regions as basis for future studies involving animal models of disturbed BMD. An automated interface which will give information on human - mouse synteny between human marker intervals of interest was developed which will expedite future synteny studies.

This thesis makes recommendations for the design of future osteoporosis prevention education for young adults through the investigation of the relationship between nutrition knowledge and perceived osteoporosis risk. Osteoporosis is a significant public health issue in Canada and nutrition represents an important component of current osteoporosis prevention education. Most osteoporosis prevention is designed for older adults, excluding young adults who are making decisions that will affect their future disease risk. Designing osteoporosis prevention for young adults means creating tailored prevention programs for young adults. Using a mixed method approach that involved a survey, food frequency questionnaire (FFQ), qualitative interviews, and a pile sort activity, I explored how the interactions between perceptions of nutrition and health, dietary practices, and constructions of disease risk affected participation in osteoporosis prevention behaviors in sixty Canadian young adults (17-30 years). Three research questions represented the core of this investigation: How do perceptions of dietary intake of calcium and vitamin D compare to measured intake? How do perceptions of osteoporosis risk contribute to preventative dietary behaviors? Where and how do young adults acquire knowledge about bone health and nutrition and how can this be used to inform the design of prevention programs? These questions are addressed in this ‘sandwich’ thesis in three papers that have been submitted for publication. Canadian young adults have been identified as having low dietary intake of calcium and vitamin D, which are essential nutrients for maintaining bone health. Understanding calcium and vitamin D consumption practices is therefore necessary to create targeted messaging that will result in greater intake of these nutrients. The majority of participants were found to perceive their intake of calcium and vitamin D to be adequate, when in fact they were estimated through the FFQ to be consuming inadequate amounts of both nutrients. Participants explained their perceptions of their diet as adequate due to their belief that their diet was healthy, the perceived absence of any nutrition-related symptoms, and the belief that calcium and vitamin D were present in many foods in their diet. Addressing these assumptions and encouraging young adults to question their intake is necessary in engaging them with prevention education and modifying dietary behaviors. Osteoporosis risk is heavily gendered in contemporary prevention programs that primarily target women. This differential focus creates disparities in how risk is understood in terms of perceived susceptibility, severity, and individuals’ self-efficacy in undertaking prevention behaviors. The use of the Health Belief Model as a framework to investigate these perceptions of risk revealed that while neither gender was motivated to engage in osteoporosis prevention, beliefs about individual risk of disease were a negotiation between larger gender constructs of osteoporosis and a variety of risk factors. The design of new prevention programs needs to address these differential understandings of risk and create targeted education plans for men and women. This study shows that designing prevention programs means adopting effective knowledge translation methods that recognize the sources of information that young adults rely on and their nutrition- and health-related interests. Making use of traditional (e.g., parents, doctors) and emerging (e.g., social media) sources, while creating messaging that is short, relatable and linked to current interests will help create prevention programs that engage young adults and motivate them to participate in prevention. The increasing incidence of osteoporosis signals a need for expanded prevention programs that move beyond the current at-risk population. To be effective these new programs need to address both the nutrition beliefs of young adults and the perceptions of disease risk in order to holistically address the barriers to engagement with prevention information experienced by this age group. / Thesis / Doctor of Philosophy (PhD)

Determinar los factores de riesgo para osteoporosis en pacientes de sexo femenino que acuden al consultorio externo del servicio de Reumatología del Hospital Nacional Edgardo Rebagliati Martins. Determinar si existen diferencias entre el número de factores de riesgo entre las pacientes con osteoporosis y sin osteoporosis. Determinar si existen diferencias entre el número de factores de riesgo entre las pacientes antecedente de fractura o sin ella. MÉTODOS: Se realizó un estudio transversal que incluyó a 1800 mujeres que acudieron a la consulta externa del Servicio de Reumatología del HNERM entre Enero de 1998 y Diciembre del 2000. A cada paciente se le realizó una densitometría ósea DEXA, evaluándose columna lumbar anteroposterior, cadera y radio ultradistal. Se elaboró una ficha de factores de riesgo en la que se consignó si la paciente presentaba alguna(s) de las siguientes variables: edad mayor de 50 años , raza blanca o amarilla, peso menor de 50 kilos, talla menor de 1.50 metros, consumo de tabaco, alcohol o café, inmovilización prolongada, antecedentes familiares de osteoporosis, antecedente de artritis reumatoide, enfermedad tiroidea, diabetes mellitus o fracturas, postmenopausia, menopausia temprana, menopausia quirúrgica y uso de anticonvulsivantes. Posteriormente se determinó el odds ratio (OR) y los intervalos de confianza al 95% usando un modelo de regresión logística en el programa SPSS

OBJETIVOS: Determinar los factores de riesgo para osteoporosis en pacientes de sexo femenino que acuden al consultorio externo del servicio de Reumatología del Hospital Nacional Edgardo Rebagliati Martins. Determinar si existen diferencias entre el número de factores de riesgo entre las pacientes con osteoporosis y sin osteoporosis. Determinar si existen diferencias entre el número de factores de riesgo entre las pacientes antecedente de fractura o sin ella. MÉTODOS: Se realizó un estudio transversal que incluyó a 1800 mujeres que acudieron a la consulta externa del Servicio de Reumatología del HNERM entre Enero de 1998 y Diciembre del 2000. A cada paciente se le realizó una densitometría ósea DEXA, evaluándose columna lumbar anteroposterior, cadera y radio ultradistal. Se elaboró una ficha de factores de riesgo en la que se consignó si la paciente presentaba alguna(s) de las siguientes variables: edad mayor de 50 años , raza blanca o amarilla, peso menor de 50 kilos, talla menor de 1.50 metros, consumo de tabaco, alcohol o café, inmovilización prolongada, antecedentes familiares de osteoporosis, antecedente de artritis reumatoide, enfermedad tiroidea, diabetes mellitus o fracturas, postmenopausia, menopausia temprana, menopausia quirúrgica y uso de anticonvulsivantes. Posteriormente se determinó el odds ratio (OR) y los intervalos de confianza al 95% usando un modelo de regresión logística en el programa SPSS

Diss. (sammanfattning) Uppsala : Univ., 2001. / Härtill 5 uppsatser.

Thesis (M.S.P.H.)--University of Louisville, 2003. / Department of Bioinformatics and Biostatistics. Vita. "December 2003." Includes bibliographical references (leaves 41-46).