Fracture incidence and changes in quality of life in women with an inadequate clinical outcome from osteoporosis therapy: the Observational Study of Severe Osteoporosis (OSSO)

In this observational study of women with an inadequate clinical outcome to osteoporosis therapy, those with a fracture at baseline were more likely to sustain an incident fracture and have a worse health-related quality of life than those without prior fracture.

INTRODUCTION

The Observational Study of Severe Osteoporosis (OSSO) was designed to assess the fracture incidence and health-related quality of life (HRQoL) in women with an inadequate clinical outcome to osteoporosis therapy.

METHODS

Post-menopausal women (N=1,885) with established osteoporosis and an inadequate clinical response to osteoporosis drug therapy defined as: a) a fragility fracture despite therapy for one year (index fracture, N=988), or b) discontinued drug therapy due to adverse effects and/or non-compliance (N=897), were assessed during one year for HRQoL using the EQ-5D and the QUALEFFO questionnaires.

RESULTS

One hundred and sixty-six (8.8%) women had a total of 209 incident fractures (1,139 fractures/10,000 women-years). Women with an index fracture were more likely to sustain an incident fracture than those without prior fractures (hazard ratio 1.91; 95% CI: 1.37-2.66; p<0.001). Co-morbidities or antidepressant use at baseline also increased the risk of incident fracture. Median total EQ-5D Health State Values and QUALEFFO scores were worse in women with an incident fracture regardless of index fracture status. The worst scores were reported in the EQ-5D sub-domains of self-care, usual activities and pain/discomfort.

CONCLUSIONS

Women with an inadequate response to osteoporosis therapy had a high rate of incident fracture which had an adverse impact on HRQoL.

Beta-cell replacement and regeneration: Strategies of cell-based therapy for type 1 diabetes mellitus

Pancreatic islet transplantation has demonstrated that long-term insulin independence may be achieved in patients suffering from diabetes mellitus type 1. However, because of limited availability of islet tissue, new sources of insulin producing cells that are responsive to glucose are required. Development of pancreatic beta-cell lines from rodent or human origin has progressed slowly in recent years. Current experiments for ex vivo expansion of beta cells and in vitro differentiation of embryonic and adult stem cells into insulin producing beta-cell phenotypes led to promising results. Nevertheless, the cells generated to date lack important characteristics of mature beta cells and generally display reduced insulin secretion and loss of proliferative capacity. Therefore, much better understanding of the mechanisms that regulate expansion and differentiation of stem/progenitor cells is necessary. Here, we review recent advances in the identification of potential cellular sources, and the development of strategies to regenerate or fabricate insulin producing and glucose sensing cells that might enable future cell-based therapies of diabetes mellitus type 1.

[Metabolic bone diseases]

Osteomalacia is caused by impaired vitamin D receptor (VDR) signaling, calcium deficiency, and altered bone mineralization. This can be due to insufficient sunlight exposure, malabsorption, reduced D hormone activation in chronic kidney disease, and rare alterations of VDR signaling and phosphate metabolism. Leading symptoms are bone pain, muscular cramps, and increased incidence of falls in the elderly. The adequate respective countermeasures are to optimize the daily intake of calcium and vitamin D3 and to replace active D hormone and phosphate if deficient. Osteoporosis is characterized by bone fragility fractures upon minor physical impact. Indications for diagnosis and treatment can be established by estimating the absolute fracture risk, taking into account bone mineral density, age, gender, and individual risk factors. Exercise, intervention programs to avoid falls, and specific drugs are capable of substantially reducing fracture risk even in the elderly. Secondary osteoporosis primarily requires both bone-altering medications and effective treatment of underlying diseases.

Characterization of patients with an inadequate clinical outcome from osteoporosis therapy: the Observational Study of Severe Osteoporosis (OSSO)

BACKGROUND

Osteoporotic fractures remain a major public health problem. Currently available osteoporosis therapies significantly reduce the risk of fractures, but up to 50% of patients have an inadequate clinical outcome to therapy.

AIM

To describe the clinical and quality of life (QOL) of a study population meeting a proposed definition of inadequate clinical outcome to osteoporosis therapy, recruited for the Observational Study of Severe Osteoporosis (OSSO).

DESIGN

Cross-sectional, observational study.

METHODS

Post-menopausal women with osteoporosis (n = 2314) were divided into Group 1 (those who had previously experienced a fragility fracture despite osteoporosis drug therapy for at least 12 months) (n = 1309, 57%), or Group 2 (those who had previously discontinued osteoporosis drug therapy due to non-compliance or side-effects) (n = 1005; 43%). Baseline clinical characteristics, quality of life (QOL) and osteoporosis/falls risk factors were analysed.

RESULTS

The overall population had low BMD (mean +/- SD T-score at lumbar spine -3.1 +/- 1.1), and risk factors for fracture such as previous fractures (67.8%), family history (15.1%), and prolonged glucocorticoid use (17.5%). QOL was poor: total QUALEFFO and EQ-5D scores were 46.8 +/- 18.7, and 0.50 +/- 0.33, respectively. Patients in Group 1 had higher age and body mass index, fewer hours of exercise, more previous fragility fractures and falls, and poorer QOL scores.

DISCUSSION

Our definition of inadequate clinical outcome from osteoporosis drug therapy identifies a severe osteoporosis cohort with poor QOL and increased fracture risk. Using such a definition may lead to earlier recognition of inadequate clinical outcome to osteoporosis therapy, and improved interventions and results.

Expression of the angiomatrix and angiogenic proteins CYR61, CTGF, and VEGF in osteonecrosis of the femoral head

Angiogenesis and bone repair are closely linked processes. VEGF, CYR61, and CTGF have been identified as signaling factors that control angiogenesis and could be important in fracture healing. The purpose of this study was to investigate the expression of these signaling factors in osteonecrosis of the femoral head. Twenty-one bone cylinders were retrieved from hips of patients with osteonecrosis of the femoral head at different ARCO stages. Immunohistochemistry for CD34, CYR61, CTGF, and VEGF expression was done on each bone cylinder representing the different regions of osteonecrosis (necrosis, fibrosis, transition zone, and edematous area). VEGF, CYR61, and CTGF were expressed in samples with osteonecrosis. Particularly VEGF and CYR61 were highly expressed in the edematous area. CYR61 was also highly expressed in the transition zone. CTGF was expressed mainly in the area of marrow fibrosis and edema. CYR61, CTGF, and VEGF are expressed to different degrees in the different repair zones of osteonecrosis. Particularly, the high expression of VEGF and CYR61 in the edematous area may represent a consequence of hypoxia and indicate a role of these proteins in the repair processes ongoing in osteonecrosis.

Selenium, the thyroid, and the endocrine system

Recent identification of new selenocysteine-containing proteins has revealed relationships between the two trace elements selenium (Se) and iodine and the hormone network. Several selenoproteins participate in the protection of thyrocytes from damage by H(2)O(2) produced for thyroid hormone biosynthesis. Iodothyronine deiodinases are selenoproteins contributing to systemic or local thyroid hormone homeostasis. The Se content in endocrine tissues (thyroid, adrenals, pituitary, testes, ovary) is higher than in many other organs. Nutritional Se depletion results in retention, whereas Se repletion is followed by a rapid accumulation of Se in endocrine tissues, reproductive organs, and the brain. Selenoproteins such as thioredoxin reductases constitute the link between the Se metabolism and the regulation of transcription by redox sensitive ligand-modulated nuclear hormone receptors. Hormones and growth factors regulate the expression of selenoproteins and, conversely, Se supply modulates hormone actions. Selenoproteins are involved in bone metabolism as well as functions of the endocrine pancreas and adrenal glands. Furthermore, spermatogenesis depends on adequate Se supply, whereas Se excess may impair ovarian function. Comparative analysis of the genomes of several life forms reveals that higher mammals contain a limited number of identical genes encoding newly detected selenocysteine-containing proteins.

[Primary and secondary osteoporosis. The important role of internal medicine in its differential diagnosis]

Bone metabolism as an important part of internal medicine is covered by endocrinologists, rheumatologists and nephrologists. Primary osteoporosis is an inheritable metabolic bone disease, which can be strongly modified by lifestyle, ageing and underlying diseases. Chronic inflammatory diseases, disorders of metabolism and nutritional deficits enhance the risk. Secondary osteoporosis is caused by endocrinological disorders and drugs such as glucocorticoids. It is the task of internists to clinically recognise and diagnose prominent individual risk factors for primary osteoporosis and underlying diseases for secondary osteoporosis. The key competence of internal medicine in metabolism, hormone-related disorders, malignant diseases and in handling complex medical treatment modalities represents an indispensable segment of an interdisciplinary network approach in patient care, research and teaching. This network includes orthopaedic surgery, paediatrics and gynaecology in addition to other specialties.