Fracture risk prediction: importance of age, BMD and spine fracture status.

Our purpose was to identify factors for a parsimonious fracture risk assessment model considering morphometric spine fracture status, femoral neck bone mineral density (BMD) and the World Health Organization (WHO) clinical risk factors. Using data from 2761 subjects from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective, longitudinal cohort study of randomly selected community-dwelling men and women aged ⩾50 years, we previously reported that a logistic regression model considering age, BMD and spine fracture status provided as much predictive information as a model considering these factors plus the remaining WHO clinical risk factors. The current analysis assesses morphometric vertebral fracture and/or nonvertebral fragility fracture at 5 years using data from an additional 1964 CaMos subjects who have now completed 5 years of follow-up (total N=4725).

Peak bone mass from longitudinal data: implications for the prevalence, pathophysiology, and diagnosis of osteoporosis.

We estimated peak bone mass (PBM) in 615 women and 527 men aged 16 to 40 years using longitudinal data from the Canadian Multicentre Osteoporosis Study (CaMos). Individual rates of change were averaged to find the mean rate of change for each baseline age. The age range for PBM was defined as the period during which bone mineral density (BMD) was stable.

Health-related quality of life in Canadian adolescents and young adults: normative data using the SF-36.

Objectives: Normative data for the SF-36 measure of health-related quality of life (HRQOL) exist for those over 25 years of age, based on data from the population-based Canadian Multicentre Osteoporosis Study (CaMos). CaMos recently recruited a sample of young Canadians aged between 16 and 24 years. The purpose of this study was to develop normative SF-36 data for this age group.

Vertebral fracture status and the World Health Organization risk factors for predicting osteoporotic fracture risk.

Vertebral fractures are the most common osteoporotic fracture, and patients with prevalent vertebral fractures have a greater risk of future fractures. However, radiographically determined vertebral fractures are not identified as a distinct risk factor in the World Health Organization (WHO) fracture risk assessment tool. The objective of this study was to evaluate and compare potential risk factors including morphometric spine fracture status and the WHO risk factors for predicting 5-yr fracture risk.

Association between change in BMD and fragility fracture in women and men.

Our objective was to estimate the relationship between longitudinal change in BMD and fragility fractures. We studied 3635 women and 1417 men 50-85 yr of age in the Canadian Multicentre Osteoporosis Study who had at least two BMD measurements (lumbar spine, femoral neck, total hip, and trochanter) within the first 5 yr of the study and fragility fractures (any, main, forearm/wrist, ribs, hip) within the first 7 yr. Multiple logistic regression was used to model the relationship between baseline BMD, BMD change, and fragility fractures.

Geographic variation of bone mineral density and selected risk factors for prediction of incident fracture among Canadians 50 and older.

Background: Striking geographic variation in the incidence of osteoporotic fracture has been shown in national and international studies. The contributing risk factors for this variation are not fully understood.

Objective: To determine the geographic variation of bone mineral density (BMD) values, prevalent low-trauma fracture, prior falls, and vertebral deformity and to determine how this variation is related to the geographic variation of incident low-trauma fracture.

Change in bone mineral density as a function of age in women and men and association with the use of antiresorptive agents.

Background: Measurement of bone mineral density is the most common method of diagnosing and assessing osteoporosis. We sought to estimate the average rate of change in bone mineral density as a function of age among Canadians aged 25-85, stratified by sex and use of antiresorptive agents.

Methods: We examined a longitudinal cohort of 9423 participants.

Changes to osteoporosis prevalence according to method of risk assessment.

Unlabelled: The impact of clinical risk factor-based absolute risk methods on the prevalence of high risk for osteoporotic fracture is unknown. We applied absolute risk methods to 6646 subjects and found that the prevalence of elderly women deemed to be at high risk increased substantially, whereas the overall prevalence was highly dependent on the threshold used to designate high risk.

Introduction: Many groups have advocated using absolute risk methods that incorporate clinical risk factors to target patients for osteoporosis therapy.

Bone strength: the whole is greater than the sum of its parts.

Objective: To summarize the current knowledge regarding the various determinants of bone strength.

Methods: Relevant English-language articles acquired from Medline from 1966 up to January 2005 were reviewed. Searches included the keywords bone AND 1 of the following: strength, remodeling, microcrack, structur*, mineralization, collagen, organic, crystallinity, osteocyte, porosity, diameter, anisotropy, stress risers, or connectivity.

The effects of antifracture therapies on the components of bone strength: assessment of fracture risk today and in the future.

Objective: To summarize the current knowledge regarding the impact of the most common antifracture medications on the various determinants of bone strength.

Methods: Relevant English-language articles acquired from Medline from 1966 to January 2005 were reviewed. Searches included the keywords bone AND 1 of the following: strength, remodeling, microcrack, structure, mineralization, collagen, organic, crystallinity, osteocyte, porosity, diameter, anisotropy, stress risers, or connectivity AND alendronate, estrogen, etidronate, hormone replacement therapy, parathyroid hormone, risedronate, OR teriparatide.

Determinants of health-related quality of life in women with vertebral fractures.

Health-related quality of life (HRQL) is an important consideration in the management of patients with vertebral fractures. The purpose of this study was to examine patient-related factors that contribute to HRQL after vertebral fractures, including co-morbidities, medications, fracture history, family disease history, demographics, exercise, education and living environment. A total of 1,129 post-menopausal women (mean age 67.

Are oral bisphosphonates effective in improving lumbar bone mineral density in breast cancer survivors with osteopenia or osteoporosis?

Objective: Breast cancer survivors with osteoporosis or osteopenia are commonly encountered in primary care and gynaecology practices. Our objective was to determine whether treatment with oral bisphosphonates (alendronate or cyclic etidronate) was more effective than calcium with vitamin D in improving lumbar spine bone mineral density (BMD) within one year in breast cancer survivors.

Methods: Breast cancer survivors with at least one year of clinical follow-up were identified from the prospective observational Canadian Database of Osteoporosis and Osteopenia (CANDOO).

Predictive value of BMD for hip and other fractures.

Unlabelled: The relationship between BMD and fracture risk was estimated in a meta-analysis of data from 12 cohort studies of approximately 39,000 men and women. Low hip BMD was an important predictor of fracture risk. The prediction of hip fracture with hip BMD also depended on age and z score.

Univariate and bivariate variance component linkage analysis of a whole-genome scan for loci contributing to bone mineral density.

Osteoporosis is a common condition characterized by reduced skeletal strength and increased susceptibility to fracture. The single major risk factor for osteoporosis is low bone mineral density (BMD) and strong evidence exists that genetic factors are in part responsible for an individual's BMD. A cohort of 40 multiplex Caucasian families selected through a proband with osteoporosis was genotyped for microsatellite markers spaced at an average of 10 cM, and linkage to femoral neck (FN), lumbar spine (LS) and trochanter (TR) BMD was analyzed using univariate and bivariate variance component linkage analysis.

A meta-analysis of milk intake and fracture risk: low utility for case finding.

A low intake of calcium is widely considered to be a risk factor for future fracture. The aim of this study was to quantify this risk on an international basis and to explore the effect of age, gender and bone mineral density (BMD) on this risk. We studied 39,563 men and women (69% female) from six prospectively studied cohorts comprising EVOS/EPOS, CaMos, DOES, the Rotterdam study, the Sheffield study and a cohort from Gothenburg.

Stability of normative data for the SF-36: results of a three-year prospective study in middle-aged Canadians.

Background: The SF-36 is widely used to assess health-related quality of life (HRQOL), but with few longitudinal studies in healthy populations, it is difficult to quantify its natural history. This is important because any measure of change following an intervention may be confounded by natural changes in HRQOL. This paper assesses mean changes in SF-36 scores over a 3-year period in men and women between the ages of 40 and 59 years at baseline.

Are there differences between men and women prescribed bisphosphonate therapy in canadian subspecialty osteoporosis practices?

Objective: To determine if there are differences between men and women referred for treatment of osteoporosis in Canada.

Methods: We performed an observational study of 1588 patients (163 men, 1425 women), 50 years of age and older, who were prescribed cyclic etidronate or alendronate for treatment of osteoporosis or osteopenia and had at least 2 years of followup registered in the Canadian Database for Osteoporosis and Osteopenia Patients (CANDOO). Comparisons of characteristics between men and women were performed using Pearson chi-square test, Student's t test, or a Kruskal-Wallis test, whichever was most appropriate.

Alcohol intake as a risk factor for fracture.

High intakes of alcohol have adverse effects on skeletal health, but evidence for the effects of moderate consumption are less secure. The aim of this study was to quantify this risk on an international basis and explore the relationship of this risk with age, sex, and bone mineral density (BMD). We studied 5,939 men and 11,032 women from three prospectively studied cohorts comprising CaMos, DOES, and the Rotterdam Study.

A meta-analysis of prior corticosteroid use and fracture risk.

Unlabelled: The relationship between use of corticosteroids and fracture risk was estimated in a meta-analysis of data from seven cohort studies of approximately 42,000 men and women. Current and past use of corticosteroids was an important predictor of fracture risk that was independent of prior fracture and BMD.

Introduction: The aims of this study were to validate that corticosteroid use is a significant risk factor for fracture in an international setting and to explore the effects of age and sex on this risk.

What predicts early fracture or bone loss on bisphosphonate therapy?

Factors predicting early fracture or bone loss on bisphosphonate therapy are not well defined. We studied 1588 patients over the age of 50 yr who were started on cyclic etidronate (1119) or alendronate (469) in the CANDOO (Canadian Database for Osteoporosis and Osteopenia Patients) Study. Incident fracture within 2 yr of starting therapy occurred in 31 patients and was independently predicted by a previous history of nonvertebral fracture (odds ratio [OR], 2.

Adherence to bisphosphonates and hormone replacement therapy in a tertiary care setting of patients in the CANDOO database.

Therapies for osteoporosis must be taken for at least 1 year to be effective. The purpose of this study was to determine the difference in adherence to etidronate, alendronate and hormone replacement therapy in a group of patients seen at our tertiary care centres. The Canadian Database of Osteoporosis and Osteopenia (CANDOO), a prospective observational database designed to capture clinical data, was searched for patients who started therapy following entry into CANDOO.

Multiple imputation to account for missing data in a survey: estimating the prevalence of osteoporosis.

Background: Nonresponse bias is a concern in any epidemiologic survey in which a subset of selected individuals declines to participate.

Methods: We reviewed multiple imputation, a widely applicable and easy to implement Bayesian methodology to adjust for nonresponse bias. To illustrate the method, we used data from the Canadian Multicentre Osteoporosis Study, a large cohort study of 9423 randomly selected Canadians, designed in part to estimate the prevalence of osteoporosis.

Is there regional variation in the SF-36 scores of Canadian adults?

Background: Canadian normative data for the Medical Outcomes Study 36-item short form (SF-36) have recently been published. However, there is evidence from other countries to suggest that regional variation in health-related quality of life (HRQOL) may exist. We therefore examined the SF-36 data from nine Canadian centres for evidence of systematic differences.

The impact of incident vertebral and non-vertebral fractures on health related quality of life in postmenopausal women.

Background: Little empirical research has examined the multiple consequences of osteoporosis on quality of life.

Methods: Health related quality of life (HRQL) was examined in relationship to incident fractures in 2009 postmenopausal women 50 years and older who were seen in consultation at our tertiary care, university teaching hospital-affiliated office and who were registered in the Canadian Database of Osteoporosis and Osteopenia (CANDOO) patients. Patients were divided into three study groups according to incident fracture status: vertebral fractures, non-vertebral fractures and no fractures.