Using the same bone density reference database for men and women provides a simpler estimation of fracture risk
Lisa Langsetmo, William D Leslie, Wei Zhou
David Goltzman, Christopher S Kovacs, Jerilynn C Prior, W P Olszynski, Tassos Anastassiades, Tanveer Towheed, Stephanie Kaiser , Nancy Kreiger , CaMOS Research Group , David A Hanley, K Shawn Davison, Robert G Josse
Although low bone mineral density (BMD) predicts fractures, there are postulated sex differences in the fracture "threshold." Some studies demonstrate a higher mean BMD for men with fractures than for women, whereas others note similar absolute risk at the same level of BMD. Our objective was to test the preceding observations in the population-based Canadian Multicentre Osteoporosis Study (CaMOS). We included participants 50+ years of age at baseline. Mean BMD in men was higher than in women among both fracture cases and noncases. Three methods of BMD normalization were compared in age-adjusted Cox proportional hazards models. In a model using the same reference population mean and standard deviation (SD), there were strong effects of age and total-hip BMD for prediction of fractures but no significant effect of sex [hazard ratio (HR) = 0.97, 95% confidence interval (CI) 0.78-1.20] for men versus women. In a model using sex-specific reference means but a common SD, an apparent sex difference emerged (HR = 0.66, 95% CI 0.54-0.81) for men versus women. The sex term in the second model counterbalanced the higher risk introduced by the lower normalized BMD in men. A third model using sex-specific reference means and SDs gave nearly identical results. Parallel results for the three methods of normalization were seen when adjusting for clinical risk factors, excluding antiresorptive users and considering death as a competing risk. We conclude that no adjustment for sex is necessary when using common reference data for both men and women, whereas using sex-specific reference data requires a substantial secondary adjustment for sex.
bone density reference database universal, sex-specific bone density standards, fracture threshold men women, bone mineral density T-score sex, unified BMD reference population, osteoporosis diagnosis men women, bone density standard simplification, fracture risk BMD threshold, DXA reference values universal, bone density normative data
PMID 20499356 20499356 DOI 10.1002/jbmr.112 10.1002/jbmr.112
Cite this article
Langsetmo, L., Leslie, W. D., Zhou, W., Goltzman, D., Kovacs, C. S., Prior, J., Josse, R., Olszynski, W. P., Davison, K. S., Anastassiades, T., Towheed, T., Hanley, D. A., Kaiser, S., Kreiger, N., & CaMOS Research Group (2010). Using the same bone density reference database for men and women provides a simpler estimation of fracture risk. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research, 25(10), 2108-2114. https://doi.org/10.1002/jbmr.112
Langsetmo L, Leslie WD, Zhou W, Goltzman D, Kovacs CS, Prior J, et al. Using the same bone density reference database for men and women provides a simpler estimation of fracture risk. J Bone Miner Res. 2010;25(10):2108-2114. doi:10.1002/jbmr.112
Langsetmo, L., et al. "Using the same bone density reference database for men and women provides a simpler estimation of fracture risk." Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research, vol. 25, no. 10, 2010, pp. 2108-2114.
Many medications used in older adults have strong anticholinergic (ACH) properties, which may increase the risk of falls and fractures. Use of these medications was identified in a population-based Canadian cohort. To identify the fall and fracture risk associated with ACH medication use. Data collection and analysis were conducted at baseline, year 5, and year 10. Cross-sectional analyses were performed to examine associations between ACH medication use and falls. Time-dependent Cox regression was used to examine time to first nontraumatic fracture. Finally, change in bone mineral density (BMD) over 10 years was compared in ACH medication users versus nonusers. Strongly ACH medications were used by 618 of 7753 participants (8.0%) at study baseline, 592 (9.5%) at year 5, and 334 (7.7%) at year 10. Unadjusted ACH medication use was associated with falls at baseline (odds ratio = 1.50; 95% CI = 1.14-1.98; P = 0.004), but the association was no longer significant after covariate adjustment. Similar results occurred at years 5 and 10. ACH medication use was associated with increased incident fracture risk before (hazard ratio = 1.22; CI = 1.13-1.32; P < 0.001) but not after covariate adjustment. Mean (SD) change in femoral neck BMD T-score over 10 years, in those using ACH medications at both years 0 and 5, was -0.60 (0.63) in ACH users versus -0.49 (0.45) in nonusers (P = 0.041), but this was not significant after covariate adjustment. ACH medications were not found to be independently associated with an increased risk of falling, fractures, or BMD loss. Rather, factors associated with ACH medication use explained the apparent associations.
We used data from a large, prospective Canadian cohort to assess the association between selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs) and fracture. We found an increased risk of fractures in individuals who used SSRI or SNRI, even after controlling for multiple risk factors.
Previous studies have suggested an association between SSRIs and increasing risk of fragility fractures. However, the majority of these studies were not long-term analyses or were performed using administrative data and, thus, could not fully control for potential confounders. We sought to determine whether the use of SSRIs and SNRIs is associated with increased risk of fragility fracture, in adults aged 50 + . We used data from the Canadian Multicentre Osteoporosis Study (CaMos), a prospective randomly selected population-based community cohort; our analyses focused on subjects aged 50+. Time to event methodology was used to assess the association between SSRI/SNRI use, modeled time-dependently, and fragility fracture. Among 6,645 subjects, 192 (2.9%) were using SSRIs or/and SNRIs at baseline. During the 10-year study period, 978 (14.7%) participants experienced at least one fragility fracture. In our main analysis, SSRI/SNRI use was associated with increased risk of fragility fracture (hazard ratio (HR), 1.88; 95% confidence intervals (CI), 1.48-2.39). After controlling for multiple risk factors, including Charlson score, previous falls, and bone mineral density hip and lumbar bone density, the adjusted HR for current SSRI/SNRI use remained elevated (HR, 1.68; 95% CI, 1.32-2.14). Our results lend additional support to an association between SSRI/SNRI use and fragility fractures. Given the high prevalence of antidepressants use, and the impact of fractures on health, our findings may have a significant clinical impact.
Increasing 25-hydroxyvitamin D serum levels can prevent a wide range of diseases. There is a concern about increasing kidney stone risk with vitamin D supplementation. We used GrassrootsHealth data to examine the relationship between vitamin D status and kidney stone incidence. The study included 2012 participants followed prospectively for a median of 19 months. Thirteen individuals self-reported kidney stones during the study period. Multivariate logistic regression was applied to assess the association between vitamin D status and kidney stones. We found no statistically significant association between serum 25-hydroxyvitamin D and kidney stones (P = .42). Body mass index was significantly associated with kidney stone risk (odds ratio = 3.5; 95% confidence interval = 1.1, 11.3). We concluded that a serum 25-hydroxyvitamin D level of 20 to 100 nanograms per milliliter has no significant association with kidney stone incidence.
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