Demographic risk factors for fracture in First Nations people.

BACKGROUND: Recently, First Nations people were shown to be at high fracture risk compared with the general population. However, factors contributing to this risk have not been examined. This analysis focusses on geographic area of residence, income level, and diabetes mellitus as possible explanatory variables since they have been implicated in the fracture rates observed in other populations. METHODS: A retrospective, population-based matched cohort study of fracture rates was performed using the Manitoba administrative health data (1987-1999). The First Nations cohort included all Registered First Nations adults (20 years or older) as indicated in either federal and/or provincial files (n = 32,692). Controls (up to three for each First Nations subject) were matched by year of birth, sex and geographic area of residence. After exclusion of unmatched subjects, analysis was based upon 31,557 First Nations subjects and 79,720 controls. RESULTS: Overall and site-specific fracture rates were significantly higher in the First Nations cohort. Income quintile, geographic area of residence, and diabetes were fracture determinants but the excess fracture risk of First Nations ethnicity persisted even after adjustment for these factors. CONCLUSION: First Nations people are at high risk for fracture but the causal factors contributing to this are unclear. Further research is needed to evaluate the importance of other potential explanatory variables.

Fracture risk among First Nations people: a retrospective matched cohort study.

BACKGROUND: Canadian First Nations people have unique cultural, socioeconomic and health-related factors that may affect fracture rates. We sought to determine the overall and site-specific fracture rates of First Nations people compared with non-First Nations people. METHODS: We studied fracture rates among First Nations people aged 20 years and older (n = 32 692) using the Manitoba administrative health database (1987-1999). We used federal and provincial sources to identify ethnicity, and we randomly matched each First Nations person with 3 people of the same sex and year of birth who did not meet this definition of First Nations ethnicity (n = 98 076). We used a provincial database of hospital separations and physician billing claims to calculate standardized incidence ratios (SIRs) and 95% confidence intervals (CIs) for each fracture type based on a 5-year age strata. RESULTS: First Nations people had significantly higher rates of any fracture (age- and sex-adjusted SIR 2.23, 95% CI 2.18-2.29). Hip fractures (SIR 1.88, 95% CI 1.61-2.14), wrist fractures (SIR 3.01, 95% CI 2.63-3.42) and spine fractures (SIR 1.93, 95% CI 1.79-2.20) occurred predominantly in older people and women. In contrast, craniofacial fractures (SIR 5.07, 95% CI 4.74-5.42) were predominant in men and younger adults. INTERPRETATION: First Nations people are a previously unidentified group at high risk for fracture.

A randomized comparison of radioiodine doses in Graves' hyperthyroidism.

The optimal method for determining iodine-131 treatment doses for Graves' hyperthyroidism is unknown, and techniques have varied from a fixed dose to more elaborate calculations based upon gland size, iodine uptake, and iodine turnover. Patients with Graves' hyperthyroidism (n = 88) who had not been previously treated with radioactive iodine were randomized to one of four dose calculation methods: low-fixed, 235 MBq; high-fixed, 350 MBq; low-adjusted, 2.96 MBq (80 micro Ci)/g thyroid adjusted for 24 h radioiodine uptake; and high-adjusted, 4.44 MBq (120 micro Ci)/g thyroid adjusted for 24 h radioiodine uptake. Subjects were followed for mean of 63 months (range, 10-94 months) for the following clinical outcomes: euthyroid without medication, hyperthyroid requiring further radioiodine, and hypothyroid requiring life-long L-T(4). Mean treatment doses were similar in the different outcome groups. We could not demonstrate any advantage to using an adjusted dose method. Survival analysis did not demonstrate any difference in the time to outcome between the fixed and adjusted dose methods. The use of a fixed dose method simplifies the approach to treatment with potential cost savings.

Bone mineral density testing in healthy postmenopausal women. The role of clinical risk factor assessment in determining fracture risk.

The ease of measurement and the quantitative nature of bone mineral densitometry (BMD) is clinically appealing. Despite BMD's proven capability to stratify fracture risk, data indicate that clinical risk factors provide complementary information on fracture susceptibility that is independent of BMD. Methods to quantify fracture risk using both clinical and BMD variables would have great appeal for clinical decision-making. We describe a procedure for quantifying hip fracture risk (5-yr and remaining lifetime) based on (1) the individual's age alone (base model, assuming average clinical risk factors and bone density), (2) incorporation of multiple patient-specific clinical risk factor data in the base model, and (3) incorporation of both patient-specific clinical risk factor data and BMD results.