Health Perceptions, Multimorbidity, and New Fractures and Mortality Among Patients With a Fracture

Importance

A high proportion of patients who sustain a fracture have multimorbidity. However, the association of multimorbidity with postfracture adverse outcomes, such as subsequent fractures and premature mortality, has not been widely explored.

Objective

To examine the association of multimorbidity and self-rated health with subsequent fractures and mortality after fracture.

Design, Setting, and Participants

This prospective cohort study included participants from New South Wales, Australia, in the Sax Institute's 45 and Up Study (n = 267 357). Participants were recruited from July 2005 to December 2009 and followed up from the date of the incident fracture until subsequent fracture, death, or the end of the study (April 2017), whichever occurred first, with questionnaire data linked to hospital admission and medication records. Data analysis was reported between March and September 2023.

Exposures

Charlson Comorbidity Index (CCI) score and self-rated health (SRH).

Main Outcomes and Measures

The main outcomes were subsequent fracture or mortality after an incident fracture. Associations between SRH measures and subsequent fracture and mortality were also assessed. All analyses were stratified by sex given the different fracture and mortality risk profiles of females and males.

Results

Of 25 280 adults who sustained incident fractures, 16 191 (64%) were female (mean [SD] age, 74 [12] years) and 9089 (36%) were male (mean [SD] age, 74 [13] years). During a median follow-up time of 2.8 years (IQR, 1.1-5.2 years), 2540 females (16%) and 1135 males (12%) sustained a subsequent fracture and 2281 females (14%) and 2140 males (24%) died without a subsequent fracture. Compared with a CCI score of less than 2, those with a CCI score of 2 to 3 had an increased risk of subsequent fracture (females: hazard ratio [HR], 1.16 [95% CI, 1.05-1.27]; males: HR, 1.25 [95% CI, 1.09-1.43]) and mortality (females: HR, 2.19 [95% CI, 1.99-2.40]; males: HR, 1.89 [95% CI, 1.71-2.09]). Those with a CCI score of 4 or greater had greater risks of subsequent fracture (females: HR, 1.33 [95% CI, 1.12-1.58]; males: HR, 1.48 [95% CI, 1.21-1.81]) and mortality (females: HR, 4.48 [95% CI, 3.97-5.06]; males: HR, 3.82 [95% CI 3.41-4.29]). Self-rated health was also significantly associated with subsequent fracture and mortality. Those reporting the poorest health and quality of life had the highest subsequent fracture risks, and their mortality risks were even higher.

Conclusions and Relevance

In this cohort study, both CCI and SRH measures were associated with increased risk of subsequent fractures and mortality after fracture, underscoring the importance of managing the care of patients with comorbidities who sustain a fracture.

Patient Self-Assessment of Walking Ability and Fracture Risk in Older Australian Adults

Importance

The relationship between self-reported walking limitation, a proxy of muscle function, and fracture risk has not been investigated.

Objective

To examine the association between a self-reported walking limitation of 1000 m or less and 5-year risk of fracture.

Design, Setting, and Participants

This prospective cohort study compared individuals with various degrees of walking ability limitation at 1000 m (a little limitation and a lot of limitation) and those without limitation (no limitation) accounting for age, falls, prior fractures, and weight. Participants from the ongoing population-based Sax Institute 45 and Up Study were followed from recruitment (2005-2008) for 5 years (2010-2013). Data analysis was conducted from July 2020 to September 2023.

Exposure

Self-reported walking limitation.

Main Outcomes and Measures

Incident fracture and site-specific fractures (hip, vertebral, and nonhip nonvertebral [NHNV] fractures).

Results

Among the 266 912 participants enrolled in the 45 and Up Study, 238 969 were included, with 126 015 (53%) women (mean [SD] age, 63 [11] years) and 112 954 (47%) men (mean [SD] age, 61 [11] years). Approximately 20% reported a degree of limitation in walking 1000 m or less at baseline (39 324 women [24%]; 23 191 men [21%]). During a mean (SD) follow-up of 4.1 (0.8) years, 7190 women and 4267 men experienced an incident fracture. Compared with participants who reported no walking limitations, a little limitation and a lot of limitation were associated with higher risk of fracture (a little limitation among women: hazard ratio [HR], 1.32; 95% CI, 1.23-1.41; a little limitation among men: HR, 1.46; 95% CI, 1.34-1.60; a lot of limitation among women: HR, 1.60; 95% CI, 1.49-1.71; a lot of limitation among men: HR, 2.03; 95% CI, 1.86-2.22). Approximately 60% of fractures were attributable to walking limitation. The association was significant for hip, vertebral, and NHNV fracture and ranged between a 21% increase to a greater than 219% increase.

Conclusions and Relevance

In this cohort study of 238 969 participants, self-reported walking limitations were associated with increased risk of fracture. These findings suggest that walking ability should be sought by clinicians to identify high-risk candidates for further assessment.

Denosumab and Mortality in a Real-World Setting: A Comparative Study

Denosumab (Dmab) is increasingly prescribed worldwide. Unlike bisphosphonates (BPs), its effect on mortality has yet to be well explored. This study examined the association between Dmab and all-cause mortality compared with no treatment in subjects with a fracture and BPs in subjects without a fracture. The study population was from the Sax Institute's 45 and Up Study (n = 267,357), a prospective population-based cohort with questionnaire data linked to hospital admissions (Admitted Patients Data Collection [APDC] data were linked by the Centre for Health Record Linkage), medication records (Pharmaceutical Benefits Scheme [PBS] provided by Services Australia), and stored securely (secure data access was provided through the Sax Institute's Secure Unified Research Environment [SURE]). The new-user cohort design with propensity-score (PS) matching was implemented. In the fracture cohort, Dmab and oral BP users were matched 1:2 to no treatment (Dmab: 617 women, 154 men; oral BPs: 615 women, 266 men). In the no-fracture cohort, Dmab users were matched 1:1 with oral BPs and zoledronic acid (Zol) users (Dmab:oral BPs: 479 men, 1534 women; Dmab:Zol: 280 men, 625 women). Mortality risk was measured using sex-specific pairwise multivariable Cox models. In the fracture cohort, compared with no treatment, Dmab was associated with 48% lower mortality in women (hazard ratio [HR] = 0.52, 95% confidence interval [CI] 0.36-0.72) but not in men. Oral BPs were associated with 44% lower mortality in both sexes (women HR = 0.56, 95% CI 0.42-0.77; men HR = 0.56, 95% CI 0.40-0.78). In the no-fracture cohort, compared with BPs, Dmab was associated with 1.5- to 2.5-fold higher mortality than oral BPs (women HR = 1.49, 95% CI 1.13-1.98; men HR = 2.74; 95% CI 1.82-4.11) but similar mortality to Zol. Dmab in women and oral BPs were associated with lower post-fracture mortality than no treatment. However, Dmab users had generally higher mortality than oral BP users in those without fractures. © 2023 American Society for Bone and Mineral Research (ASBMR).

Mortality, falls and slow walking speed are predicted by different muscle strength and physical performance measures in women and men

BACKGROUND

Different measures of muscle strength, physical performance and body size/composition are used in various sarcopenia definitions. This study investigated which baseline measures best predict incident mortality and falls, and prevalent slow walking speed in older women and men.

MATERIALS AND METHODS

Data for 899 women (mean age±standard deviation, 68.7 ± 4.3 years) and 497 men (69.4 ± 3.9 years) from the Dubbo Osteoporosis Epidemiology Study 2, comprising sixty variables for muscle strength (quadriceps strength), physical performance (walking speed, timed up and go (TUG) test, sit to stand (STS) test), body size (weight, height, body mass index) and body composition (lean mass, body fat) were included. Sex-stratified Classification and Regression Tree (CART) analyses calculated baseline variable accuracy for predicting incident mortality and falls, and prevalent slow walking speed (<0.8 m/s).

RESULTS

Over 14.5 years, 103/899 (11.5%) women and 96/497 (19.3%) men died, 345/899 (38.4%) women and 172/497 (34.6%) men had ≥1 fall, and 304/860 (35.3%) women and 172/461 (31.7%) had baseline slow walking speed (<0.8 m/s). CART models identified age and walking speed adjusted for height as the most important predictors for mortality in women, and quadriceps strength (with adjustments) as the most important predictor for mortality in men. In both sexes, STS (with adjustments) was the most important predictor for incident falls, and TUG test was the most important predictor for prevalent slow walking speed. Body composition measures were not important predictors for any outcome.

CONCLUSIONS

Muscle strength and physical performance variables and cut points predict falls and mortality differently in women and men, suggesting targeted sex-specific application of selected measures may improve outcome prediction in older adults.

Prevention of Hip Fractures: Trade-off between Minor Benefits to Individuals and Large Benefits to the Community

Goeffrey Rose postulated that a population-based measure bringing a small benefit to each individual can yield large benefits to the community. We aimed to test this axiom by quantifying the relationship between change in bone mineral density (BMD) and hip fracture incidence between two prospective cohorts separated by ~10 years. In this prospective population-based Dubbo Osteoporosis Epidemiology Study (DOES), the participants aged 60+ were recruited in two waves: the initial cohort (1311 women, 842 men) in 1989 to 1992 and the second cohort (974 women, 544 men) in 1999 to 2001. The incident hip fracture was radiologically ascertained. Femoral neck BMD was measured biannually. Multivariable-adjusted Cox's proportional hazards models were adjusted for the predefined covariates such as age, BMI, lifestyle factors, falls, and prior fracture. Compared with the initial cohort, the second cohort had a higher femoral neck BMD by ~0.04 g/cm2 in women and 0.03 g/cm2 in men. However, the prevalence of osteoporosis in the second cohort was halved (prevalence ratio 0.51, 95% CI 0.36 to 0.73 in women; 0.45, 0.24 to 0.84 in men), and its hip fracture incidence was significantly reduced (hazard ratio 0.54, 95% CI, 0.38 to 0.78 in women; 0.39, 0.19 to 0.80 in men). Sensitivity analyses indicated that the "effect" was unlikely due to unmeasured confounders. These findings suggest that a population-wide strategy aimed at enhancing BMD across the entire population could lead to a substantial decrease in the incidence of hip fractures. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Associations of Type 2 Diabetes, Body Composition, and Insulin Resistance with Bone Parameters: The Dubbo Osteoporosis Epidemiology Study

Type 2 diabetes (T2D) may be associated with increased risk of fractures, despite preserved bone mineral density (BMD). Obesity and insulin resistance (IR) may have separate effects on bone turnover and bone strength, which contribute to skeletal fragility. We characterized and assessed the relative associations of obesity, body composition, IR, and T2D on bone turnover markers (BTMs), BMD, and advanced hip analysis (AHA). In this cross-sectional analysis of Dubbo Osteoporosis Epidemiology Study, 525 (61.3% women) participants were grouped according to T2D, IR (homeostasis model assessment insulin resistance [HOMA-IR] Collapse

Key Words

• BIOCHEMICAL MARKERS OF BONE TURNOVER
• BONE‐FAT INTERACTIONS
• DUAL‐ENERGY X‐RAY ABSORPTIOMETRY
• FRACTURE RISK ASSESSMENT
• STATISTICAL METHODS

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MESH Headings Collapse

Grants

• St. Vincent's Clinic Foundation

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Affiliation(s)

Angela Sheu Skeletal Diseases ProgramGarvan Institute of Medical ResearchSydneyNSWAustralia School of Clinical Medicine, UNSW Medicine and Health, St Vincent's Clinical Campus, Faculty of Medicine and HealthUNSW SydneySydneyNSWAustralia Department of Endocrinology and DiabetesSt Vincent's HospitalSydneyNSWAustralia
Robert D. Blank Skeletal Diseases ProgramGarvan Institute of Medical ResearchSydneyNSWAustralia
Thach Tran Skeletal Diseases ProgramGarvan Institute of Medical ResearchSydneyNSWAustralia School of Clinical Medicine, UNSW Medicine and Health, St Vincent's Clinical Campus, Faculty of Medicine and HealthUNSW SydneySydneyNSWAustralia
Dana Bliuc Skeletal Diseases ProgramGarvan Institute of Medical ResearchSydneyNSWAustralia School of Clinical Medicine, UNSW Medicine and Health, St Vincent's Clinical Campus, Faculty of Medicine and HealthUNSW SydneySydneyNSWAustralia
Jerry R. Greenfield Skeletal Diseases ProgramGarvan Institute of Medical ResearchSydneyNSWAustralia School of Clinical Medicine, UNSW Medicine and Health, St Vincent's Clinical Campus, Faculty of Medicine and HealthUNSW SydneySydneyNSWAustralia Department of Endocrinology and DiabetesSt Vincent's HospitalSydneyNSWAustralia
Christopher P. White School of Clinical Medicine, Prince of Wales Clinical Campus, Faculty of Medicine and HealthUNSW SydneySydneyNSWAustralia Department of Endocrinology and MetabolismPrince of Wales HospitalSydneyNSWAustralia
Jacqueline R. Center Skeletal Diseases ProgramGarvan Institute of Medical ResearchSydneyNSWAustralia School of Clinical Medicine, UNSW Medicine and Health, St Vincent's Clinical Campus, Faculty of Medicine and HealthUNSW SydneySydneyNSWAustralia Department of Endocrinology and DiabetesSt Vincent's HospitalSydneyNSWAustralia

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Safer medicines To reduce falls and refractures for OsteoPorosis (#STOP): a study protocol for a randomised controlled trial of medical specialist-initiated pharmacist-led medication management reviews in primary care

INTRODUCTION

Minimal trauma fractures (MTFs) often occur in older patients with osteoporosis and may be precipitated by falls risk-increasing drugs. One category of falls risk-increasing drugs of concern are those with sedative/anticholinergic properties. Collaborative medication management services such as Australia's Home Medicine Review (HMR) can reduce patients' intake of sedative/anticholinergics and improve continuity of care. This paper describes a protocol for an randomised controlled trial to determine the efficacy of an HMR service for patients who have sustained MTF.

METHOD AND ANALYSIS

Eligible participants are as follows: ≥65 years of age, using ≥5 medicines including at least one falls risk-increasing drug, who have sustained an MTF and under treatment in one of eight Osteoporosis Refracture Prevention clinics in Australia. Consenting participants will be randomised to control (standard care) or intervention groups. For the intervention group, medical specialists will refer to a pharmacist for HMR focused on reducing falls risk predominately through making recommendations to reduce falls risk medicines, and adherence to antiosteoporosis medicines. Twelve months from treatment allocation, comparisons between groups will be made. The main outcome measure is participants' cumulative exposure to sedative and anticholinergics, using the Drug Burden Index. Secondary outcomes include medication adherence, emergency department visits, hospitalisations, falls and mortality. Economic evaluation will compare the intervention strategy with standard care.

ETHICS AND DISSEMINATION

Approval was obtained via the New South Wales Research Ethics and Governance Information System (approval number: 2021/ETH12003) with site-specific approvals granted through Human Research Ethics Committees for each research site. Study outcomes will be published in peer-reviewed journals. It will provide robust insight into effectiveness of a pharmacist-based intervention on medicine-related falls risk for patients with osteoporosis. We anticipate that this study will take 2 years to fully accrue including follow-up.

TRIAL REGISTRATION NUMBER

ACTRN12622000261718.

MCP-1 expression in breast cancer and its association with distant relapse

BACKGROUND

Distant relapse of breast cancer complicates management of the disease and accounts for 90% of breast cancer-related deaths. Monocyte chemoattractant protein-1 (MCP-1) has critical roles in breast cancer progression and is widely accepted as a pro-metastatic chemokine.

METHODS

This study explored MCP-1 expression in the primary tumour of 251 breast cancer patients. A simplified 'histoscore' was used to determine if each tumour had high or low expression of MCP-1. Patient breast cancers were retrospectively staged based on available patient data. p < 0.05 was used to determine significance and changes in hazard ratios between models were considered.

RESULTS

Low MCP-1 expression in the primary tumour was associated with breast cancer-related death with distant relapse in ER- breast cancers (p < 0.01); however, this was likely a result of most low MCP-1-expressing ER- breast cancers being Stage III or Stage IV, with high MCP-1 expression in the primary tumour significantly correlated with Stage I breast cancers (p < 0.05). Expression of MCP-1 in the primary ER- tumours varied across Stage I, II, III and IV and we highlighted a switch in MCP-1 expression from high in Stage I ER- cancers to low in Stage IV ER- cancers.

CONCLUSION

This study has emphasised a critical need for further investigation into MCP-1's role in breast cancer progression and improved characterisation of MCP-1 in breast cancers, particularly in light of the development of anti-MCP-1, anti-metastatic therapies.

'Skeletal Age' for mapping the impact of fracture on mortality

Background

Fragility fracture is associated with an increased risk of mortality, but mortality is not part of doctor-patient communication. Here, we introduce a new concept called 'Skeletal Age' as the age of an individual's skeleton resulting from a fragility fracture to convey the combined risk of fracture and fracture-associated mortality for an individual.

Methods

We used the Danish National Hospital Discharge Register which includes the whole-country data of 1,667,339 adults in Denmark born on or before January 1, 1950, who were followed up to December 31, 2016 for incident low-trauma fracture and mortality. Skeletal age is defined as the sum of chronological age and the number of years of life lost (YLL) associated with a fracture. Cox's proportional hazards model was employed to determine the hazard of mortality associated with a specific fracture for a given risk profile, and the hazard was then transformed into YLL using the Gompertz law of mortality.

Results

During the median follow-up period of 16 years, there had been 307,870 fractures and 122,744 post-fracture deaths. A fracture was associated with between 1 and 7 years of life lost, with the loss being greater in men than women. Hip fractures incurred the greatest loss of life years. For instance, a 60-year-old individual with a hip fracture is estimated to have a skeletal age of 66 for men and 65 for women. Skeletal Age was estimated for each age and fracture site stratified by gender.

Conclusions

We propose 'Skeletal Age' as a new metric to assess the impact of a fragility fracture on an individual's life expectancy. This approach will enhance doctor-patient risk communication about the risks associated with osteoporosis.

Funding

National Health and Medical Research Council in Australia and Amgen Competitive Grant Program 2019.

Effects of bariatric surgery and dietary intervention on insulin resistance and appetite hormones over a 3 year period

To examine an impact of three types of bariatric surgery compared with dietary intervention (DIET), on concurrent changes in Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and appetite hormones over 3 years. Fifty-five adults were studied during phase of weight loss (0-12 months) and during weight stability (12-36 months) post intervention. Measurements of HOMA-IR, fasting and postprandial PYY and GLP1, adiponectin, CRP, RBP4, FGF21 hormones and dual-Xray absorptiometry were performed throughout the study. All surgical groups achieved significant reductions in HOMA-IR with greatest difference between Roux-en-Y gastric bypass and DIET (- 3.7; 95% CI - 5.4, - 2.1; p = 0.001) at 12-36 months. Initial (0-12 months) HOMA-IR values were no different to DIET after adjustment for the lost weight. During 12-36 months, after controlling for treatment procedure and weight, for every twofold increase in postprandial PYY and adiponectin, HOMA-IR decreased by 0.91 (95% CI - 1.71, - 0.11; p = 0.030) and by 0.59 (95% CI - 1.10, - 0.10; p = 0.023) respectively. Initial, non-sustained changes in RBP4 and FGF21 were not associated with HOMA-IR values. While initial rapid weight loss reduces insulin resistance, the enhanced secretions of PYY and adiponectin may contribute to weight-independent improvements in HOMA-IR during weight stability.Clinical trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12613000188730.

Antiresorptive Medication Use Is not Associated With Acute Cardiovascular Risk: An Observational Study

CONTEXT

Bisphosphonates have been reported to be cardioprotective in some, but not all, studies. It is unknown whether denosumab (Dmab) use protects against cardiovascular events (CVEs).

OBJECTIVE

To determine whether oral bisphosphonate (oBP) or Dmab use is associated with CVEs in persons with incident fracture.

METHODS

Participants with an incident minimal trauma fracture from the Sax Institute's 45 and Up Study, a population-based cohort from NSW, Australia, were followed between 2005/2009 and 2017. Questionnaire data were linked to hospital admissions (Admitted Patients Data Collection [APDC]) by the Centre for Health Record Linkage). Medicare Benefit Schedule (MBS) and Pharmaceutical Benefits Scheme (PBS) data sets were provided by Services Australia. Data was stored in a secure computing environment (Secure Unified Research Environment). Fractures, CVEs, and comorbidities were identified from the APDC and oBP and Dmab medication from the PBS. oBP and Dmab users were matched to never users (NoRx) by propensity scores. The main outcome measures were association between oBP and Dmab with CVE (acute myocardial infarction, unstable angina, cerebrovascular accident, and transient ischemic attack) and were determined using a stratified Cox's proportional hazards model.

RESULTS

There were 880 pairs of oBP and NoRx (616 women) and 770 pairs of Dmab and NoRx (615 women) followed for ∼4.3 years. CVE risk was similar for oBP and NoRx Hazard Ratios (HR) women, 0.88 [95% CI 0.65-1.18]; men, 1.07 [95% CI 0.72-1.57]). Similar findings were obtained for Dmab (Hazard Ratios (HR) women, 1.08 [95% CI 0.78-1.50]; men, 1.55 [95% CI 0.96-2.48]).

CONCLUSION

oBP and Dmab use was not associated with CVEs.

Muscle strength and physical performance contribute to and improve fracture risk prediction in older people: A narrative review

Osteoporotic fractures present a major health problem with an increasing prevalence in older people. Fractures are associated with premature mortality, reduced quality of life, subsequent fracture, and increased costs. Hence, it is crucial to identify those at higher risk of fracture. Fracture risk assessment tools incorporated clinical risk factors to improve fracture predictive power over BMD alone. However, fracture risk prediction using these algorithms remains suboptimal, warranting further improvement. Muscle strength and physical performance measurements have been associated with fracture risk. In contrast, the contribution of sarcopenia, the composite condition of low muscle mass, muscle strength and/or physical performance, to fracture risk is unclear. It is uncertain whether this is due to the problematic definition of sarcopenia per se or limitations of the diagnostic tools and cut-off points of the muscle mass component. The recent position statement from the Sarcopenia Definition and Outcomes Consortium confirmed the inclusion of muscle strength and performance in the definition of sarcopenia but not DXA-assessed lean mass. Therefore, clinicians should focus on functional assessment (muscle strength and performance) rather than muscle mass, at least as assessed by DXA, as predictors of fractures. Muscle strength and performance are modifiable risk factors. Resistance exercise improves muscle parameters in the elderly, potentially leading to reduced risk of falls and fractures in the general population and in those who sustained a fracture. Therapists may consider exercise intervention to improve muscle parameters and potentially reduce the risk of fractures. The aim of this review was to explore 1) the contribution of muscle parameters (i.e., muscle mass, strength, and physical performance) to fracture risk in older adults, and 2) the added predictive accuracy of these parameters beyond the existing fracture assessment tools. These topics provide the rationale for investigating strength and physical performance interventions to reduce fracture risk. Most of the included publications showed that muscle mass is not a good predictor of fracture risk, while poor muscle strength and performance are associated with an increased risk of fracture, particularly in men, independent of age, BMD, and other risk factors for fractures. Muscle strength and performance can potentially improve the predictive accuracy in men beyond that obtained by the fracture risk assessment tools, Garvan FRC and FRAX.

Predictors for pharmacological therapy and perinatal outcomes with metformin treatment in women with gestational diabetes

BACKGROUND

The prevalence of gestational diabetes mellitus (GDM) has been increasing in Australia and worldwide. The study aims were to examine, in comparison with dietary intervention, perinatal outcomes for women with gestational diabetes who were attending a single hospital clinic and to identify predictors for their pharmacological GDM treatment.

METHODS

A prospective, observational study of women with GDM, treated with "Diet, N= 50", "Metformin, N = 35", "Metformin and Insulin, N = 46" or "Insulin, N = 20".

FINDINGS

The mean BMI for the whole cohort was 25.8 ± 4.7 kg/m². The Metformin group, compared to the Diet group, had OR=3.1 (95% CI:1.13 to 8.25) for caesarean section birth (LSCS) compared to normal vaginal birth mode with no longer such a significant association after controlling for the number of their elective LSCS. The insulin treated group had the highest number of small for gestational age neonates (20%, p<0.05) with neonatal hypoglycaemia (25%, p< 0.05). Fasting glucose value on oral GTT (glucose tolerance test) was the strongest predictor for a pharmacological intervention requirement with OR = 2.77 (95CI%: 1.16 to 6.61), followed by timing of OGTT with OR=0.90 (95% CI: 0.83 to 0.97) and previous pregnancy loss with OR=0.28 (95% CI:0.10 to 0.74).

INTERPRETATION

These data suggest that metformin may be a safe alternative treatment to insulin treatment in GDM. Raised fasting glucose on oral GTT was the strongest indicator that GDM women with BMI < 35 kg/m² may require pharmacological therapy. Further studies are needed to identify the most effective and safe management of gestational diabetes within the public hospital setting.

AUSTRALIAN NEW ZEALAND CLINICAL TRIAL REGISTRY ANZCTR TRIAL ID

ACTRN12620000397910.

Association of Multimorbidity and Excess Mortality After Fractures Among Danish Adults

IMPORTANCE

Limited knowledge about interactions among health disorders impedes optimal patient care. Because comorbidities are common among patients 50 years and older with fractures, these fractures provide a useful setting for studying interactions among disorders.

OBJECTIVE

To define multimorbidity clusters at the time of fracture and quantify the interaction between multimorbidity and fracture in association with postfracture excess mortality.

DESIGN, SETTING, AND PARTICIPANTS

This nationwide cohort study included 307 870 adults in Denmark born on or before January 1, 1951, who had an incident low-trauma fracture between January 1, 2001, and December 31, 2014, and were followed up through December 31, 2016. Data were analyzed from February 1 to March 31, 2022.

MAIN OUTCOMES AND MEASURES

Fracture and 32 predefined chronic diseases recorded within 5 years before the index fracture were identified from the Danish National Hospital Discharge Register. Death was ascertained from the Danish Register on Causes of Death. Latent class analysis was conducted to identify multimorbidity clusters. Relative survival analysis was used to quantify excess mortality associated with the combination of multimorbidity and fractures at specific sites.

RESULTS

Among the 307 870 participants identified with incident fractures, 95 372 were men (31.0%; mean [SD] age at fracture, 72.3 [11.2] years) and 212 498 were women (69.0%; mean [SD] age at fracture, 74.9 [11.2] years). During a median of 6.5 (IQR, 3.0-11.0) years of follow-up, 41 017 men (43.0%) and 81 727 women (38.5%) died. Almost half of patients with fractures (42.9%) had at least 2 comorbidities. Comorbidities at fracture were categorized as low-multimorbidity (60.5% in men and 66.5% in women), cardiovascular (23.7% in men and 23.5% in women), diabetic (5.6% in men and 5.0% in women), malignant (5.1% in men and 5.0% in women), and mixed hepatic and/or inflammatory (5.1% in men only) clusters. These clusters distinguished individuals with advanced, complex, or late-stage disease from those with earlier-stage disease. Multimorbidity and proximal or lower leg fractures were associated with increased mortality risk, with the highest excess mortality found in patients with hip fracture in the malignant cluster (1-year excess mortality: 40.8% [95% CI: 38.1%-43.6%]). The combination of multimorbidity and fracture compounded the association with mortality, conferring much greater risk than either alone.

CONCLUSIONS AND RELEVANCE

Concomitant illnesses were common and clustered into distinct multimorbidity clusters that were associated with excess postfracture mortality. The compound contribution of multimorbidity to postfracture excess mortality highlights the need for more comprehensive approaches in these high-risk patients. The analytical approach applied to fracture could also be used to examine other sentinel health events.

Muscle Strength and Physical Performance Are Associated With Risk of Postfracture Mortality But Not Subsequent Fracture in Men

Muscle strength and physical performance are associated with incident fractures and mortality. However, their role in the risk of subsequent fracture and postfracture mortality is not clear. We assessed the association between muscle strength (grip strength) and performance (gait speed and chair stands time) and the risk of subsequent fracture and mortality in 830 men with low-trauma index fracture, who participated in the Osteoporotic Fractures in Men (MrOS) USA Study and had their index measurements assessed within 5 years prior to the index fracture. The annual decline in muscle strength and performance following index fracture, estimated using linear mixed-effects regression, was also examined in relation to mortality. The associations were assessed using Cox proportional hazards models adjusted for age, femoral neck bone mineral density (FN BMD), prior fractures, falls, body mass index (BMI), index fracture site, lifestyle factors, and comorbidities. Over a median follow-up of 3.7 (interquartile range [IQR], 1.3-8.1) years from index fracture to subsequent fracture, 201 (24%) men had a subsequent fracture and over 5.1 (IQR, 1.8-9.6) years to death, and 536 (65%) men died. Index measurements were not associated with subsequent fracture (hazard ratios [HRs] ranging from 0.97 to 1.07). However, they were associated with postfracture mortality. HR (95% confidence interval [CI]) per 1 standard deviation (1-SD) decrement in grip strength: HR 1.12 (95% CI, 1.01-1.25) and gait speed: HR 1.14 (95% CI, 1.02-1.27), and 1-SD increment in chair stands time: HR 1.08 (95% CI, 0.97-1.21). Greater annual declines in these measurements were associated with higher mortality risk, independent of the index values and other covariates. HR (95% CI) per 1-SD annual decrement in change in grip strength: HR 1.15 (95% CI, 1.01-1.33) and in gait speed: HR 1.38 (95% CI, 1.13-1.68), and 1-SD annual increment in chair stands time: HR 1.28 (95% CI, 1.07-1.54). Men who were unable to complete one or multiple tests had greater risk of postfracture mortality (24%-109%) compared to those performed all tests. It remains to be seen whether improvement in these modifiable factors can reduce postfracture mortality. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Association between incident falls and subsequent fractures in patients attending the fracture liaison service after an index fracture: a 3-year prospective observational cohort study

OBJECTIVES

To evaluate the risk of subsequent fractures in patients who attended the Fracture Liaison Service (FLS), with and without incident falls after the index fracture.

DESIGN

A 3-year prospective observational cohort study.

SETTING

An outpatient FLS in the Netherlands.

PARTICIPANTS

Patients aged 50+ years with a recent clinical fracture.

OUTCOME MEASURES

Incident falls and subsequent fractures.

RESULTS

The study included 488 patients (71.9% women, mean age: 64.6±8.6 years). During the 3-year follow-up, 959 falls had been ascertained in 296 patients (60.7%) (ie, fallers), and 60 subsequent fractures were ascertained in 53 patients (10.9%). Of the fractures, 47 (78.3%) were fall related, of which 25 (53.2%) were sustained at the first fall incident at a median of 34 weeks. An incident fall was associated with an approximately 9-fold (HR: 8.6, 95% CI 3.1 to 23.8) increase in the risk of subsequent fractures.

CONCLUSION

These data suggest that subsequent fractures among patients on treatment prescribed in an FLS setting are common, and that an incident fall is a strong predictor of subsequent fracture risk. Immediate attention for fall risk could be beneficial in an FLS model of care.

TRIAL REGISTRATION NUMBER

NL45707.072.13.

Fractures in type 2 diabetes confer excess mortality: The Dubbo osteoporosis epidemiology study

PURPOSE

Diabetes and fractures are both associated with increased mortality, however the effect of the combination is not well-established. We examined the mortality risk following all types of fractures in type 2 diabetes (T2D).

METHODS

In the Dubbo Osteoporosis Epidemiology Study (1989-2017), participants were grouped according to T2D and/or incident fracture. Study outcome was all-cause mortality. First incident radiological fragility fracture and incident T2D diagnosis were time-dependent variables. Cox's proportional hazards models quantified mortality risk associated with T2D and incident fracture overall, as well as by fracture site, T2D duration and T2D medication type.

RESULTS

In 3618 participants (62% women), 272 had baseline and 179 developed T2D over median 13.0 years (IQR 8.2-19.6). 796 women (56 with T2D) and 240 men (25 with T2D) sustained a fracture. Compared to those without T2D or fracture, mortality risk increased progressively, in T2D without fracture, then no T2D with fracture, and was highest in those with T2D with fracture (adjusted hazard ratio (aHR) (95% CI) for women 2.62 (1.75-3.93) and men 2.61 (1.42-4.81)). Within T2D participants, incident fracture was associated with increased mortality (aHR for women 1.87 (1.10-3.16) and men 2.83 (1.41-5.68)), especially following hip/vertebral fractures in men (aHR 2.97 (1.29-6.83)) and non-hip non-vertebral fractures in women (aHR 2.42 (1.24-4.75)), and in T2D duration >5 years.

CONCLUSION

Any fracture in T2D conferred significant excess mortality. Individuals with T2D should be carefully monitored post-fracture, especially if T2D >5 years. Optimising fracture prevention and post-fracture management in T2D is critical and warrants further studies.

Muscle Strength and Physical Performance Improve Fracture Risk Prediction Beyond Garvan and FRAX: The Osteoporotic Fractures in Men (MrOS) Study

Muscle strength and physical performance are associated with fracture risk in men. However, it is not known whether these measurements enhance fracture prediction beyond Garvan and FRAX tools. A total of 5665 community-dwelling men, aged ≥65 years, from the Osteoporotic Fractures in Men (MrOS) Study, who had data on muscle strength (grip strength) and physical performance (gait speed and chair stand tests), were followed from 2000 to 2019 for any fracture, major osteoporotic fracture (MOF), initial hip, and any hip fracture. The contributions to different fracture outcomes were assessed using Cox's proportional hazard models. Tool-specific analysis approaches and outcome definitions were used. The added predictive values of muscle strength and physical performance beyond Garvan and FRAX were assessed using categorical net reclassification improvement (NRI) and relative importance analyses. During a median follow-up of 13 (interquartile range 7-17) years, there were 1014 fractures, 536 MOFs, 215 initial hip, and 274 any hip fractures. Grip strength and chair stand improved prediction of any fracture (NRI for grip strength 3.9% and for chair stand 3.2%) and MOF (5.2% and 6.1%). Gait speed improved prediction of initial hip (5.7%) and any hip (7.0%) fracture. Combining grip strength and the relevant performance test further improved the models (5.7%, 8.9%, 9.4%, and 7.0% for any, MOF, initial, and any hip fractures, respectively). The improvements were predominantly driven by reclassification of those with fracture to higher risk categories. Apart from age and femoral neck bone mineral density, muscle strength and performance were ranked equal to or better than the other risk factors included in fracture models, including prior fractures, falls, smoking, alcohol, and glucocorticoid use. Muscle strength and performance measurements improved fracture risk prediction in men beyond Garvan and FRAX. They were as or more important than other established risk factors. These measures should be considered for inclusion in fracture risk assessment tools. © 2021 American Society for Bone and Mineral Research (ASBMR).

Cognitive decline is associated with an accelerated rate of bone loss and increased fracture risk in women: a prospective study from the Canadian Multicentre Osteoporosis Study

Cognitive decline and osteoporosis often coexist and some evidence suggests a causal link. However, there are no data on the longitudinal relationship between cognitive decline, bone loss and fracture risk, independent of aging. This study aimed to determine the association between: (i) cognitive decline and bone loss; and (ii) clinically significant cognitive decline (≥3 points) on Mini Mental State Examination (MMSE) over the first 5 years and subsequent fracture risk over the following 10 years. A total of 1741 women and 620 men aged ≥65 years from the population-based Canadian Multicentre Osteoporosis Study were followed from 1997 to 2013. Association between cognitive decline and (i) bone loss was estimated using mixed-effects models; and (ii) fracture risk was estimated using adjusted Cox models. Over 95% of participants had normal cognition at baseline (MMSE ≥ 24). The annual % change in MMSE was similar for both genders (women -0.33, interquartile range [IQR] -0.70 to +0.00; and men -0.34, IQR: -0.99 to 0.01). After multivariable adjustment, cognitive decline was associated with bone loss in women (6.5%; 95% confidence interval [CI], 3.2% to 9.9% for each percent decline in MMSE from baseline) but not men. Approximately 13% of participants experienced significant cognitive decline by year 5. In women, fracture risk was increased significantly (multivariable hazard ratio [HR], 1.61; 95% CI, 1.11 to 2.34). There were too few men to analyze. There was a significant association between cognitive decline and both bone loss and fracture risk, independent of aging, in women. Further studies are needed to determine mechanisms that link these common conditions. © 2021 American Society for Bone and Mineral Research (ASBMR).

Current status and distribution of hip fractures among older adults in China

China is a middle-risk country for hip fracture at present, which differs from previous data that it was low-risk. By 2050, the total number of hip fractures in people older than 65 years is predicted to be 1.3 million.

INTRODUCTION

To assess hip fracture incidence in China and examine the heterogeneity of hip fracture in seven geographical regions of China.

METHODS

There were 238,230 hip fracture patients aged 65 years or older from 2013 to 2016 from a large national in-patients database (HQMS) involving 30.6 million hospitalizations. Taking into account the total national hospitalization rate per calendar year, we estimated the incidence of hip fracture per 100,000 residents older than 65 years in China overall and in seven geographical Chinese regions.

RESULTS

The proportion of men and women older than 65 years with hip fractures was 1.00:1.95. Between 2013 and 2016, the number of hip fractures per 100,000 people age 65+ was 278. China has vast territories; the number of hip fractures per 100,000 people over 65 years old was 202 in Northeast China and 374 in Northwest China. Northwest has higher altitude, lower population density, is less developed with lower urbanization than Northeast China which is low altitude, and highly urbanized.

CONCLUSIONS

China should no longer be regarded as a low-risk country for hip fracture. By 2050, the total number of hip fractures in people older than 65 years in China is predicted to be 1.3 million. Higher altitude areas had higher hip fracture rates than lower altitude, higher urbanized areas.

Multimorbidity Increases Risk of Osteoporosis Under-Diagnosis and Under-Treatment in Patients at High Fracture Risk: 45 and up a Prospective Population Based-Study

Background: Management of osteoporosis following fracture is suboptimal. Multimorbidity adds to clinical management complexity in the elderly but its contribution to the osteoporosis treatment gap has never been investigated. Objectives: To determine the impact of multimorbidity on fracture risk and on osteoporosis investigation and treatment in patients at high fracture risk. Design and Setting: The 45 and Up Study is a prospective population-based cohort study in NSW, Australia with questionnaire data linked to hospital records by the Centre for Health Record Linkage (CHeReL) and the Pharmaceutical Benefits Scheme (PBS) and Medicare Benefits Scheme (MBS) data provided by Department of Human Services. Fractures identified from hospital records, comorbidities from questionnaires, hospital and PBS records. Bone mineral density (BMD) investigation obtained from MBS and treatment for osteoporosis from PBS. Participants: 16191 women and 9089 men with incident low-trauma fracture (2000 - 2017) classified in a high and low-risk group based on 10-year fracture risk threshold of 20% from the Garvan Fracture Risk Calculator (age, gender, prior fracture and falls). Main Outcome Measurements: Association of Charlson comorbidity index (CCI) with fracture. Likelihood of BMD investigation and treatment initiation. Outcomes ascertained by logistic regression and re-fracture risk by Cox models. Results: Individuals at high fracture risk were significantly older [women (mean age ±SD) 77 ± 10 vs 57 ±4 for high- vs low risk and men 86±5 vs 65±8 for high vs low risk] and had a higher morbidity burden [women, CCI ≥ 2 40% vs 12% for high- vs low-risk and men 53% vs 26% for high vs low risk]. Being in the high-risk group as well as a higher CCI were independently associated with > 2-fold higher risk of re-fracture. However, in the high-risk group, only 28% (48% women and 17% men) had a BMD investigation and 31% (24% women and 14% men) received anti-osteoporosis medication post-fracture. A higher CCI was associated with a lower probability of both BMD investigation [CCI 2–3 vs 0–1, RR 0.73 (0.65–0.82) for women, and 0.50 (0.40–0.64) for men and CCI ≥4 vs 0–1, RR 0.50 (0.41- 0.62) for women and 0.36 (0.25–0.52) for men] and treatment initiation [CCI 2–3 vs 0–1, RR 0.88 (0.77–0.98) for women and 0.75 (0.60–0.95) for men and CCI ≥4 vs 0–1, RR 0.75 (0.59- 0.95) for women and 0.35 (0.23–0.53) for men]. Conclusion: Multimorbidity, despite being associated with the highest fracture risk, significantly lowers the likelihood of osteoporosis investigation and treatment. These findings suggest that fracture risk is either under-estimated or under-prioritized in the context of multimorbidity. Our findings highlight the need for improved delivery of fracture preventive care in this setting. More generally, they also point out the need for a better understanding of how problems are prioritized in complex clinical situations.

Epidemiological transition to mortality and refracture following an initial fracture

This study sought to redefine the concept of fracture risk that includes refracture and mortality, and to transform the risk into "skeletal age". We analysed data obtained from 3521 women and men aged 60 years and older, whose fracture incidence, mortality, and bone mineral density (BMD) have been monitored since 1989. During the 20-year follow-up period, among 632 women and 184 men with a first incident fracture, the risk of sustaining a second fracture was higher in women (36%) than in men (22%), but mortality risk was higher in men (41%) than in women (25%). The increased risk of mortality was not only present with an initial fracture, but was accelerated with refractures. Key predictors of post-fracture mortality were male gender (hazard ratio [HR] 2.4; 95% CI, 1.79–3.21), advancing age (HR 1.67; 1.53–1.83), and lower femoral neck BMD (HR 1.16; 1.01–1.33). A 70-year-old man with a fracture is predicted to have a skeletal age of 75. These results were incorporated into a prediction model to aid patient-doctor discussion about fracture vulnerability and treatment decisions.

Bisphosphonates and lifespan

Bisphosphonates are first line agents used to treat osteoporosis and reduce fracture rate. They bind to areas of exposed calcium in the skeleton and cause osteoclast apoptosis, thereby leading to a reduction in remodelling rates. They are also used to decrease skeletal complications of some cancers including a reduction in bone metastases. Following the landmark randomised controlled trial of zoledronate post hip fracture (HORIZON) in which an unexpected survival benefit was found, there has been increasing interest in their potential ability to increase lifespan. This review will consider the clinical evidence for their effect on mortality in both the osteoporosis and non-osteoporosis settings, the latter including studies in intensive care, cancer and cardiovascular disease. Where evidence exists, this review will briefly discuss some of the postulated mechanisms for this survival benefit.

A Risk Assessment Tool for Predicting Fragility Fractures and Mortality in the Elderly

Existing fracture risk assessment tools are not designed to predict fracture-associated consequences, possibly contributing to the current undermanagement of fragility fractures worldwide. We aimed to develop a risk assessment tool for predicting the conceptual risk of fragility fractures and its consequences. The study involved 8965 people aged ≥60 years from the Dubbo Osteoporosis Epidemiology Study and the Canadian Multicentre Osteoporosis Study. Incident fracture was identified from X-ray reports and questionnaires, and death was ascertained though contact with a family member or obituary review. We used a multistate model to quantify the effects of the predictors on the transition risks to an initial and subsequent incident fracture and mortality, accounting for their complex interrelationships, confounding effects, and death as a competing risk. There were 2364 initial fractures, 755 subsequent fractures, and 3300 deaths during a median follow-up of 13 years (interquartile range [IQR] 7-15). The prediction model included sex, age, bone mineral density, history of falls within 12 previous months, prior fracture after the age of 50 years, cardiovascular diseases, diabetes mellitus, chronic pulmonary diseases, hypertension, and cancer. The model accurately predicted fragility fractures up to 11 years of follow-up and post-fracture mortality up to 9 years, ranging from 7 years after hip fractures to 15 years after non-hip fractures. For example, a 70-year-old woman with a T-score of -1.5 and without other risk factors would have 10% chance of sustaining a fracture and an 8% risk of dying in 5 years. However, after an initial fracture, her risk of sustaining another fracture or dying doubles to 33%, ranging from 26% after a distal to 42% post hip fracture. A robust statistical technique was used to develop a prediction model for individualization of progression to fracture and its consequences, facilitating informed decision making about risk and thus treatment for individuals with different risk profiles. © 2020 American Society for Bone and Mineral Research.

Decline in Muscle Strength and Performance Predicts Fracture Risk in Elderly Women and Men

CONTEXT

Muscle strength and performance are associated with fractures. However, the contribution of their rate of decline is unclear.

OBJECTIVE

To assess the independent contribution of the rate of decline in muscle strength and performance to fracture risk.

DESIGN, SETTING, AND PARTICIPANTS

Community-dwelling women (n = 811) and men (n = 440) aged 60 years or older from the prospective Dubbo Osteoporosis Epidemiology Study followed from 2000 to 2018 for incident fracture. Clinical data, appendicular lean mass/height2 (ht)2, bone mineral density, quadricep strength/ht (QS), timed get-up-and-go (TGUG), 5 times repeated sit-to-stand (5xSTS), and gait speed (GS) measured biennially. Rates of decline in muscle parameters were calculated using ordinary least squares regression and fracture risk was assessed using Cox's models.

MAIN OUTCOME

Incident low-trauma fracture ascertained by x-ray report.

RESULTS

Apart from lean mass in women, all muscle parameters declined over time. Greater rates of decline in physical performance were associated with increased fracture risk in women (Hazard ratios [HRs] ranging from 2.1 (95% CI: 1.5-2.9) for GS to 2.7 (95% CI: 1.9-3.6) for 5xSTS, while in men only the decline in GS was associated with fracture risk (HR: 3.4 [95% CI: 1.8-6.3]). Baseline performance and strength were also associated with increased fracture risk in men (HRs ranging from 1.8 (95% CI: 1.1-3.0) for QS to 2.5 (95% CI: 1.5-4.1) for TGUG, but not in women.

CONCLUSION

Rate of decline in physical performance in both genders, and baseline strength and performance in men, contributed independently to fracture risk. Sit-to-stand and GS were the tests most consistently associated with fractures. Further studies are required to determine whether muscle strength and/or performance improve the predictive accuracy of fracture prediction models.

OR13-03 Understanding Why Older People with Low Trauma Fractures Die Prematurely

There is increasing evidence that all proximal and not just hip fractures are associated with increased mortality risk. However, the cause of this increased mortality is unknown. We sought to determine the post-fracture trajectories of subsequent hospital admissions and mortality to develop an understanding of why patients with non-hip fractures die prematurely.

This nationwide Danish population-based study included all individuals aged 50+ years who sustained an incident fragility fracture between 2001 and 2014. High-trauma fractures or individuals with fracture prior to 2001 were excluded. Fracture patients were matched 1:4 by sex, age and comorbidity status with non-fracture subjects alive at the time of fracture. Comorbidities included 33 unique medical conditions of the Charlson or Elixhauser comorbidity index. We modelled the contribution of specific fractures on the risk of subsequent admissions or death within the following 2 years.

There were 212,498 women and 95,372 men with fracture followed by 30,677 and 19,519 deaths, respectively over 163,482 and 384,995 person-years of follow up. Mean age at fracture was 72± 11 for women and 75± 11 for men. Proximal fractures including hip, femur, pelvis, rib, clavicle and humerus had increased mortality compared with their matched non-fracture counterparts with HRs ranging from 1.5-4.0, while distal fractures such as ankle, forearm, hand or foot fractures had similar or lower mortality risk.

Almost 75% of men and 60% of women had ≥1 comorbidity. For every additional comorbidity, risk of mortality increased for all fracture types. However, only for proximal fractures did the fracture itself independently increase mortality risk over and above co-morbidity status.

The 2-yr post fracture admission and mortality patterns differed between proximal and distal fractures. Proximal, but not distal fracture subjects had greater risk of any major hospital admission (including cardiovascular disease, cancer, stroke, diabetes, pneumonia and pulmonary disease) within 2 years compared with their non-fracture counterparts. Distal fractures in general had similar admission patterns as their non-fractured matched counterparts.

Furthermore, 2 year mortality risk was increased for proximal fractures whether or not they were admitted to hospital post fracture. By contrast, mortality risk was similar or reduced for distal fractures compared with non-fracture controls.

This study has not only confirmed the increased mortality following proximal fractures but has demonstrated differing clinical trajectories between proximal and distal fractures that contribute to this increased mortality. These findings provide important insights as to why proximal fracture subjects die prematurely that may lead to specific avenues for intervention.

Oral Bisphosphonate Use and All-Cause Mortality in Patients With Moderate-Severe (Grade 3B-5D) Chronic Kidney Disease: A Population-Based Cohort Study

Oral bisphosphonates (oBPs) have been associated with reduced fractures and mortality. However, their risks and benefits are unclear in patients with moderate-severe CKD. This study examined the association between oBPs and all-cause mortality in G3B-5D CKD. This is a population-based cohort study including all subjects with an estimated glomerular filtration rate (eGFR) <45/mL/min/1.73 m² (G3B: eGFR <45/mL/min/1.73 m² G4: eGFR 15-29/mL/min/1.73 m² G5: eGFR <15/mL/min/1.73 m² G5D: hemodialysis) aged 40+ years from the UK Clinical Practice Research Datalink (CPRD) and the Catalan Information System for Research in Primary Care (SIDIAP). Previous and current users of other anti-osteoporosis drugs were excluded. oBP use was modeled as a time-varying exposure to avoid immortal time bias. Treatment episodes in oBP users were created by concatenating prescriptions until patients switched or stopped therapy or were censored or died. A washout period of 180 days was added to (date of last prescription +180 days). Propensity scores (PSs) were calculated using prespecified predictors of mortality including age, gender, baseline eGFR, socioeconomic status, comorbidities, previous fracture, co-medications, and number of hospital admissions in the previous year. Cox models were used for PS adjustment before and after PS trimming (the first and last quintiles). In the CPRD, of 19,351 oBP users and 210,954 non-oBP users, 5234 (27%) and 85,105 (40%) deaths were recorded over 45,690 and 915,867 person-years of follow-up, respectively. oBP users had 8% lower mortality risk compared to non-oBP users (hazard ratio [HR] 0.92; 95% CI, 0.89 to 0.95). Following PS trimming, this became nonsignificant (HR 0.98; 95% CI, 0.94 to 1.04). In the SIDIAP, of 4146 oBP users and 86,127 non-oBP users, 1330 (32%) and 36,513 (42%) died, respectively. oBPs were not associated with mortality in PS adjustment and trimming (HR 1.04; 95% CI, 0.99 to 1.1 and HR 0.95; 95% CI, 0.89 to 1.01). In this observational, patient-based cohort study, oBPs were not associated with increased mortality among patients with moderate-severe CKD. However, further studies are needed on other effects of oBPs in CKD patients. © 2020 American Society for Bone and Mineral Research.

Impact of osteoporotic fracture type and subsequent fracture on mortality: the Tromsø Study

Less is known about the impact of non-hip non-vertebral fractures (NHNV) on early death. This study demonstrated increased risk of dying following hip and NHNV fractures which was further increased by a subsequent fracture. This highlights the importance of early intervention to prevent both initial and subsequent fractures and improve survival.

INTRODUCTION

Osteoporotic fractures are a major health concern. Limited evidence exists on their impact on mortality in ageing populations. This study examined the contribution of initial fracture type and subsequent fracture on mortality in a Norwegian population that has one of the highest rates of fractures.

METHODS

The Tromsø Study is a prospective population-based cohort in Norway. Women and men aged 50+ years were followed from 1994 to 2010. All incident hip and non-hip non-vertebral (NHNV) fractures were registered. NHNV fractures were classified as either proximal or distal. Information on self-reported co-morbidities, lifestyle factors, general health and education level was collected. Multivariable Cox models were used to quantify mortality risk with incident and subsequent fractures analysed as time-dependent variables.

RESULTS

Of 5214 women and 4620 men, 1549 (30%) and 504 (11%) sustained a fracture, followed by 589 (38%) and 254 (51%) deaths over 10,523 and 2821 person-years, respectively. There were 403 (26%) subsequent fractures in women and 68 (13%) in men. Hip fracture was associated with a two-fold increase in mortality risk (HR 2.05, 95% CI 1.73-2.42 in women and 2.49, 95% CI 2.00-3.11 in men). Proximal NHNV fractures were associated with 49% and 81% increased mortality risk in women and men (HR 1.49, 95% CI 1.21-1.84 and 1.81, 95% CI 1.37-2.41), respectively. Distal NHNV fractures were not associated with mortality. Subsequent fracture was associated with 89% and 77% increased mortality risk in women and men (HR 1.89, 95% CI 1.52-2.35 and 1.77, 95% CI 1.16-2.71), respectively.

CONCLUSION

Hip, proximal NHNV and subsequent fractures were significantly associated with increased mortality risk in the elderly, highlighting the importance of early intervention.

Reduced Bone Loss Is Associated With Reduced Mortality Risk in Subjects Exposed to Nitrogen Bisphosphonates: A Mediation Analysis

Bisphosphonates, potent antiresorptive agents, have been found to be associated with mortality reduction. Accelerated bone loss is, in itself, an independent predictor of mortality risk, but the relationship between bisphosphonates, bone loss, and mortality is unknown. This study aimed to determine whether the association between bisphosphonates and mortality is mediated by a reduction in the rate of bone loss. Participants from the population-based Canadian Multicentre Osteoporosis Study were followed prospectively between1996 and 2011. Comorbidities and lifestyle factors were collected at baseline and bone mineral density (BMD) at baseline and at years 3 (for those aged 40 to 60 years), 5, and 10. Rate of bone loss was calculated using linear regression. Information on medication use was obtained yearly. Bisphosphonate users grouped into nitrogen bisphosphonates (nBP; alendronate or risedronate) and etidronate and non-users (NoRx) were matched by propensity score, including all baseline factors as well as time of treatment. Cox's proportional hazards models, unadjusted and adjusted for annual rate of bone loss, were used to determine the association between nBP and etidronate versus NoRx. For the treatment groups with significant mortality risk reduction, the percent of mortality reduction mediated by a reduction in the rate of bone loss was estimated using a causal mediation analysis. There were 271 pairs of nBP and matched NoRx and 327 pairs of etidronate and matched NoRx. nBP but not etidronate use was associated with significant mortality risk reduction (hazard ratios [HR] = 0.61 [95% confidence interval 0.39-0.96] and 1.35 [95% CI 0.86-2.11] for nBP and etidronate, respectively). Rapid bone loss was associated with more than 2-fold increased mortality risk compared with no loss. Mediation analysis indicated that 39% (95% CI 7%-84%) of the nBP association with mortality was related to a reduction in the rate of bone loss. This finding provides an insight into the mechanism of the relationship between nBP and survival benefit in osteoporotic patients. © 2019 American Society for Bone and Mineral Research.

Mortality risk reduction differs according to bisphosphonate class: a 15-year observational study

In this prospective cohort of 6120 participants aged 50+, nitrogen-bisphosphonates but not non-nitrogen bisphosphonates were associated with a significant 34% mortality risk reduction compared to non-treated propensity score matched controls. These findings open new avenues for research into mechanistic pathways.

INTRODUCTION

Emerging evidence suggests that bisphosphonates (BP), first-line treatment of osteoporosis, are associated with reduced risks for all-cause mortality. This study aimed to determine the association between different BP types and mortality risk in participants with or without a fracture.

METHODS

A prospective cohort study of users of different BPs matched to non-users by propensity score (age, gender, co-morbidities, fragility fracture status) and time to starting the BP medication from the population-based Canadian Multicentre Osteoporosis Study from nine Canadian centres followed from 1995 to 2013. Mortality risk for bisphosphonate users vs matched non-users was assessed using pairwise multivariable Cox proportional hazards models.

RESULTS

There were 2048 women and 308 men on BP and 1970 women and 1794 men who did not receive medication for osteoporosis. The relationship between BP and mortality risk was explored in three separate 1:1 propensity score-matched cohorts of BP users and no treatment (etidronate, n = 599, alendronate, n = 498, and risedronate n = 213). Nitrogen BP (n-BP) (alendronate and risedronate) was associated with lower mortality risks [pairwise HR, 0.66 (95% CI, 0.48-0.91)] while the less potent non-n-BP, etidronate, was not [pairwise HR: 0.89 (95% CI, 0.66-1.20)]. A direct comparison between n-BP and etidronate (n = 340 pairs) also suggested a better survival for n-BP [paired HR, 0.47 (95%CI, (95% CI, 031-0.70)] for n-BP vs. etidronate].

CONCLUSION

Compared to no treatment, nitrogen but not non-nitrogen bisphosphonates appear to be associated with better survival.

Vitamin D C3-epimer levels are proportionally higher with oral vitamin D supplementation compared to ultraviolet irradiation of skin in mice but not humans

A proportion of circulating 25-hydroxy vitamin D₃ (25(OH)D₃₎) undergoes epimerization to form C3-epi 25(OH)D₃ and C3-epi 1,25(OH)₂D₃. These epimers have less calcaemic activity than non-epimerized metabolites and are not differentiated by many immunoassays when reporting total 25(OH)D₃ levels. This study aimed to compare the effect of exposure to ultraviolet radiation (UVR) and oral vitamin D₃ supplementation on vitamin D C3-epimer levels. C57Bl/6 female mice were fed either vitamin D-sufficient (vitamin D₃ 2000 IU/kg) or -deficient diets (no vitamin D₃) for 4 weeks. Among the vitamin D-deficient group, the shaved backs of half were irradiated daily for 4 days with 1 kJ/m² UVR, followed by twice weekly irradiation for 4 weeks. Despite similar 25(OH)D₃ levels, the UV-irradiated group had a lower proportion of C3-epi 25(OH)D₃ at week 7 (p < 0.05) and week 9 (p < 0.01). C3-epimer concentrations and %C3-epi 25(OH)D₃ were also analysed in serum samples from two human clinical trials. These trials investigated the effect of high dose oral vitamin D₃ supplementation and narrowband UVB phototherapy, respectively. Serum 25(OH)D₃ and the %C3-epi 25(OH)D₃ levels measured at 12 months after oral vitamin D₃ supplementation were not significantly different to those measured at the time of maximal effect of phototherapy (2 months). Thus, the proportion of 25(OH)D₃ that undergoes epimerization is greater with oral vitamin D₃ supplementation than exposure to UVR in mice, but not in humans. This important difference between human and murine vitamin D metabolism warrants consideration when interpreting animal studies.

Persistence of Excess Mortality Following Individual Nonhip Fractures: A Relative Survival Analysis

CONTEXT

Little is known about long-term excess mortality following fragility nonhip fractures.

OBJECTIVE

The study aimed to determine which fracture was associated with excess mortality and for how long the postfracture excess mortality persisted.

DESIGN, SETTING, AND PATIENTS

This nationwide registry-based follow-up study included all individuals in Denmark aged 50+ years who first experienced fragility fractures in 2001 and were followed up for up to 10 years for their mortality risk.

MAIN OUTCOME MEASURE

The contribution of fracture to mortality at precise postfracture time intervals was examined using relative survival analysis, accounting for time-related mortality changes in the background population.

RESULTS

There were 21,123 women (aged 72 ± 13 years) and 9481 men (aged 67 ± 12 years) with an incident fragility fracture in 2001, followed by 10,668 and 4745 deaths, respectively. Excess mortality was observed following all proximal and lower leg fractures. The majority of deaths occurred within the first year after fracture, and thereafter excess mortality gradually declined. Hip fractures were associated with the highest excess mortality (33% and 20% at 1 year after fracture in men and women, respectively). One-year excess mortality after fracture of a femur or pelvis was 20% to 25%; vertebrae, 10%; humerus, rib, or clavicle, 5% to 10%; and lower leg, 3%. A significant although smaller excess mortality was still observed until 10 years for hip fractures and ~5 years after femur, other proximal, and lower leg fractures.

CONCLUSION

This study highlights the important contribution of a wide variety of fragility fractures to long-term excess mortality and thus the potential for benefit from early intervention.

The Challenges and Opportunities of Pharmacoepidemiology in Bone Diseases

Pharmacoepidemiology is used extensively in osteoporosis research and involves the study of the use and effects of drugs in large numbers of people. Randomized controlled trials are considered the gold standard in assessing treatment efficacy and safety. However, their results can have limited external validity when applied to day-to-day patients. Pharmacoepidemiological studies aim to assess the effect/s of treatments in actual practice conditions, but they are limited by the quality, completeness, and inherent bias due to confounding. Sources of information include prospectively collected (primary) as well as readily available routinely collected (secondary) (eg, electronic medical records, administrative/claims databases) data. Although the former enable the collection of ad hoc measurements, the latter provide a unique opportunity for the study of large representative populations and for the assessment of rare events at relatively low cost. Observational cohort and case-control studies, the most commonly implemented study designs in pharmacoepidemiology, each have their strengths and limitations. However, the choice of the study design depends on the research question that needs to be answered. Despite the many advantages of observational studies, they also have limitations. First, missing data is a common issue in routine data, frequently dealt with using multiple imputation. Second, confounding by indication arises because of the lack of randomization; multivariable regression and more specific techniques such as propensity scores (adjustment, matching, stratification, trimming, or weighting) are used to minimize such biases. In addition, immortal time bias (time period during which a subject is artefactually event-free by study design) and time-varying confounding (patient characteristics changing over time) are other types of biases usually accounted for using time-dependent modeling. Finally, residual "uncontrolled" confounding is difficult to assess, and hence to account for it, sensitivity analyses and specific methods (eg, instrumental variables) should be considered.

Comorbidities Only Account for a Small Proportion of Excess Mortality After Fracture: A Record Linkage Study of Individual Fracture Types

Nonhip, nonvertebral (NHNV) fractures constitute the majority of osteoporotic fractures, but few studies have examined the association between these fractures, comorbidity, and mortality. Our objective was to examine the relationship between individual nonhip, nonvertebral fractures, comorbidities, and mortality. The prospective population-based cohort of 267,043 subjects (45 and Up Study, Australia) had baseline questionnaires linked to hospital administrative and all-cause mortality data from 2006 to 2013. Associations between fracture and mortality were examined using multivariate, time-dependent Cox models, adjusted for age, prior fracture, body mass index, smoking, and comorbidities (cardiovascular disease, diabetes, stroke, thrombosis, and cancer), and survival function curves. Population attributable fraction was calculated for each level of risk exposure. During 1,490,651 person-years, women and men experienced 7571 and 4571 fractures and 7064 deaths and 11,078 deaths, respectively. In addition to hip and vertebral fractures, pelvis, humerus, clavicle, rib, proximal tibia/fibula, elbow and distal forearm fractures in both sexes, and ankle fractures in men were associated with increased multivariable-adjusted mortality hazard ratios ranging from 1.3 to 3.4. Comorbidity independently added to mortality such that a woman with a humeral fracture and 1 comorbidity had a similarly reduced 5-year survival as that of a woman with a hip fracture and no comorbidities. Population mortality attributable to any fracture without comorbidity was 9.2% in women and 5.3% in men. All proximal nonhip, nonvertebral fractures in women and men were associated with increased mortality risk. Coexistent comorbidities independently further increased mortality. Population attributable risk for mortality for fractures was similar to cardiovascular disease and diabetes, highlighting their importance and potential benefit for early intervention and treatment. © 2018 American Society for Bone and Mineral Research.

Nonstandard Lumbar Region in Predicting Fracture Risk

Femoral neck (FN) bone mineral density (BMD) is the most commonly used skeletal site to estimate fracture risk. The role of lumbar spine (LS) BMD in fracture risk prediction is less clear due to osteophytes that spuriously increase LS BMD, particularly at lower levels. The aim of this study was to compare fracture predictive ability of upper L1-L2 BMD with standard L2-L4 BMD and assess whether the addition of either LS site could improve fracture prediction over FN BMD. This study comprised a prospective cohort of 3016 women and men over 60 yr from the Dubbo Osteoporosis Epidemiology Study followed up for occurrence of minimal trauma fractures from 1989 to 2014. Dual-energy X-ray absorptiometry was used to measure BMD at L1-L2, L2-L4, and FN at baseline. Fracture risks were estimated using Cox proportional hazards models separately for each site. Predictive performances were compared using receiver operating characteristic curve analyses. There were 565 women and 179 men with a minimal trauma fracture during a mean of 11 ± 7 yr. L1-L2 BMD T-score was significantly lower than L2-L4 T-score in both genders (p < 0.0001). L1-L2 and L2-L4 BMD models had a similar fracture predictive ability. LS BMD was better than FN BMD in predicting vertebral fracture risk in women [area under the curve 0.73 (95% confidence interval, 0.68-0.79) vs 0.68 (95% confidence interval, 0.62-0.74), but FN was superior for hip fractures prediction in both women and men. The addition of L1-L2 or L2-L4 to FN BMD in women increased overall and vertebral predictive power compared with FN BMD alone by 1% and 4%, respectively (p < 0.05). In an elderly population, L1-L2 is as good as but not better than L2-L4 site in predicting fracture risk. The addition of LS BMD to FN BMD provided a modest additional benefit in overall fracture risk. Further studies in individuals with spinal degenerative disease are needed.

Population-Wide Impact of Non-Hip Non-Vertebral Fractures on Mortality

Data on long-term consequences of non-hip non-vertebral (NHNV) fractures, accounting for approximately two-thirds of all fragility fractures, are scanty. Our study aimed to quantify the population-wide impact of NHNV fractures on mortality. The national population-based prospective cohort study (Canadian Multicentre Osteoporosis Study) included 5526 community dwelling women and 2163 men aged 50 years or older followed from July 1995 to September 2013. Population impact number was used to quantify the average number of people for whom one death would be attributable to fracture and case impact number to quantify the number of deaths out of which one would be attributable to a fracture. There were 1370 fragility fractures followed by 296 deaths in women (mortality rate: 3.49; 95% CI, 3.11 to 3.91), and 302 fractures with 92 deaths in men (5.05; 95% CI, 4.12 to 6.20). NHNV fractures accounted for three-quarters of fractures. In women, the population-wide impact of NHNV fractures on mortality was greater than that of hip and vertebral fractures because of the greater number of NHNV fractures. Out of 800 women, one death was estimated to be attributable to a NHNV fracture, compared with one death in 2000 women attributable to hip or vertebral fracture. Similarly, out of 15 deaths in women, one was estimated to be attributable to a NHNV fracture, compared with one in over 40 deaths for hip or vertebral fracture. The impact of forearm fractures (ie, one death in 2400 women and one out of 42 deaths in women attributable to forearm fracture) was similar to that of hip, vertebral, or rib fractures. Similar, albeit not significant, results were noted for men. The study highlights the important contribution of NHNV fractures on mortality because many NHNV fracture types, except for the most distal fractures, have serious adverse consequences that affect a significant proportion of the population. © 2017 American Society for Bone and Mineral Research.

Determinants of mortality risk following osteoporotic fractures

PURPOSE OF REVIEW

Increased mortality risk is accepted for hip and vertebral fracture. Recent data suggest that other fracture types have also been linked to excess mortality. This article reviews the existing evidence on the pattern and determinants of postfracture mortality.

RECENT FINDINGS

The pattern of mortality over time following hip and vertebral fractures has recently been clarified. Nonhip nonvertebral fractures at major, and even minor sites in older individuals have also been associated with excess mortality. Studies have revealed the higher excess mortality in men and in younger age groups for all fracture types. Despite the increasing knowledge on the fracture-mortality association, little is known about its cause. The role of co-morbidities is inconsistent across studies. Recent findings suggest low bone mass, bone loss and muscle weakness are linked to both fracture and mortality risk, and thus may play a role in postfracture mortality.

SUMMARY

Nonhip nonvertebral fractures have recently been associated with mortality risk. Larger studies are needed to better understand which specific fractures and factors contribute to fracture-associated mortality risk. The role of bone loss in postfracture mortality needs to be validated in more studies, because of its potential reversibility with antifracture therapies.

More-than-minimal-trauma fractures are associated with low bone density: an 8-year prospective study

Few studies have examined the relationship between more-than-minimal-trauma fractures and bone density. This study demonstrated that more-than-minimal-trauma fractures are associated with lower bone density similar to that seen in minimal trauma fractures. Men and women over 50 years with a more-than-minimal-trauma fracture should be investigated to exclude low bone density.

INTRODUCTION

The aim of this study was to assess the prevalence and predictors of low bone density in men and women with more-than-minimal-trauma fractures.

METHODS

In an Australian hospital, 630 community-dwelling men and women, 20 years of age or older, sustained a fracture due to more-than-minimal-trauma (force greater than a fall from standing height but less than high trauma). We studied 349 individuals who agreed to have a bone mineral density (BMD) scan. These participants were compared with 472 men and women with minimal trauma fractures.

RESULTS

Men and women with more-than-minimal-trauma fractures had significantly lower bone density than expected for their age, gender and weight (Z-score_spine = -0.4 SD, 95 % confidence interval (CI), -0.5 to -0.3; Z-score_hip = -0.5 SD, 95 % CI, -0.6 to -0.4). Almost 1 in 4 of those over 50 years of age had osteoporosis by BMD criteria. The independent predictors of low bone density (T-score <-2.0 SD) were age equal to or over 50 years (odds ratio (OR) = 5.97, 95 % CI, 3.34 to 10.65), low body weight <20 kg/m² (OR = 3.44, 95 % CI, 1.32 to 8.94), a prior minimal trauma fracture (OR = 2.76, 95 % CI, 1.17-6.52) and in those over 50 years of age, an osteoporosis-associated condition (OR = 4.51, 95 % CI, 1.69 to 12.06). Men and women with more-than-minimal-trauma fractures had similar bone density (Z-score) compared to those with minimal trauma fractures.

CONCLUSIONS

Men and women over 50 years with a more-than-minimal-trauma fracture, especially those with low body weight, prior minimal trauma fracture or an osteoporosis-associated condition, should be investigated to exclude low bone density and its associated risk of subsequent fractures.

Secular Changes in Postfracture Outcomes Over 2 Decades in Australia: A Time-Trend Comparison of Excess Postfracture Mortality in Two Birth Controls Over Two Decades

CONTEXT

Hip fracture incidence has been declining and life expectancy improving. However, trends of postfracture outcomes are unknown.

OBJECTIVES

The objective of the study was to compare the refracture risk and excess mortality after osteoporotic fracture between two birth cohorts, over 2 decades.

DESIGN

Prospective birth cohorts were followed up over 2 decades (1989-2004 and 2000-2014).

SETTING

The study was conducted in community-dwelling participants in Dubbo, Australia.

PARTICIPANTS

Women and men aged 60-80 years, participating in Dubbo Osteoporosis Epidemiology Study 1 (DOES 1; born before 1930) and Dubbo Osteoporosis Epidemiology Study 2 (DOES 2; born after 1930) participated in the study.

MAIN OUTCOME MEASURE

Age-standardized fracture and mortality over two time intervals: (1989-2004 [DOES 1] and 2000-2014 [DOES 2]) were measured.

RESULTS

The DOES 2 cohort had higher body mass index and bone mineral density and lower initial fracture rate than DOES 1, but similar refracture rates [age-standardized refracture rates per 1000 person-years: women: 53 (95% confidence interval [CI] 42-63) and 51 (95% CI 41-60) and men: 53 (95% CI 38-69) and 55 (95% CI 40-71) for DOES 2 and DOES 1, respectively). Absolute postfracture mortality rates declined in DOES 2 compared with DOES 1, mirroring the improvement in general-population life expectancy. However, when compared with period-specific general-population mortality, there was a similar 2.1- to 2.6-fold increased mortality risk after a fracture in both cohorts (age-adjusted standardized mortality ratio, women: 2.05 [95% CI 1.43-2.83] and 2.43 [95% CI 1.95-2.99] and men: 2.56 [95% CI 1.78-3.58] and 2.48 [95% CI 1.87-3.22] for DOES 2 and DOES 1, respectively).

CONCLUSION

Over the 2 decades, despite the decline in the prevalence of fracture risk factors, general-population mortality, and initial fracture incidence, there was no improvement in postfracture outcomes. Refracture rates were similar and fracture-associated mortality was 2-fold higher than expected. These data indicate that the low postfracture treatment rates are still a major problem.

Contribution of Lumbar Spine BMD to Fracture Risk in Individuals With T-Score Discordance

Fracture risk estimates are usually based on femoral neck (FN) BMD. It is unclear how to address T-score discordance, where lumbar spine (LS) T-score is lower than FN T-score. The objective of this work was to examine the impact of LS BMD on fracture risk, in individuals with lower LS T-score than FN T-score. Participants aged 60+ years from the Dubbo Osteoporosis Epidemiology Study with LS and FN BMD measured at first visit, and were followed from 1989 to 2014. Five-hundred and seventy-three (573) of 2270 women and 131 of 1373 men had lower LS than FN T-score by ≥ 0.6 standard deviation (SD) (low-LS group based on least significant change). In low-LS women, each 1 SD lower LS T-score than FN was associated with a 30% increase in fracture risk (hazard ratio [HR] 1.30; 95% CI, 1.11 to 1.45). For low-LS men there was a 20% nonsignificant increase in fracture risk for each 1 SD lower LS than FN T-score (HR 1.20; 95% CI, 0.10 to 1.67). Low-LS women had greater absolute fracture risks than the rest of the women. This increased risk was more apparent for lower levels of FN T-score and in older age groups. At an FN T-score of -2, low-LS women had a 3%, 10%, and 23% higher 5-year absolute fracture risk than non-low LS women in the 60 to 69 year, 70 to 79 year, and 80+ years age-groups, respectively. Furthermore, an osteoporotic LS T-score increased 5-year absolute fracture risk for women with normal or osteopenic FN T-score by 10% to 13%. Men in the low-LS group had very few fractures; therefore, a meaningful analyses of fracture risk could not be conducted. This study shows the significant contribution of lower LS BMD to fracture risk over and above FN BMD in women. A LS BMD lower than FN BMD should be incorporated into fracture risk calculators at least for women in older age-groups.

Accelerated bone loss and increased post-fracture mortality in elderly women and men

Bone loss, a fracture risk factor, may play a role in post-fracture mortality. We found accelerated bone loss (≥1.31 % bone loss/year for women and ≥1.35 % bone loss/year for men) associated with 44-77 % increased mortality. It remains unclear whether bone loss is a marker or plays a role in mortality.

INTRODUCTION

Osteoporotic fractures are associated with increased mortality although the cause is unknown. Bone loss, a risk factor for osteoporotic fracture is also associated with increased mortality, but its role in mortality risk post-fracture is unclear. This study aimed to examine post-fracture mortality risk according to levels of bone loss.

METHODS

Community-dwelling participants aged 60+ from Dubbo Osteoporosis Epidemiology Study with incident fractures were followed from 1989 to 2011. Kaplan-Meier survival curves were constructed according to bone loss quartiles. Cox proportional hazard models were used to determine the effect of bone loss on mortality.

RESULTS

There were 341 women and 106 men with ≥2 BMD measurements. The rate of bone loss was similar for women and men (women mean -0.79 %/year, highest bone loss quartile -1.31 %/year; men mean -0.74 %/year, highest quartile -1.35 %/year). Survival was lowest for the highest quartile of bone loss for women (p < 0.005) and men (p = 0.05). When analysed by fracture type, the association of bone loss with mortality was observed for vertebral (highest vs lower 3 quartiles of bone loss, women p = 0.03 and men p = 0.02) and non-hip non-vertebral fractures in women (p < 0.0001). Bone loss did not play an additional role in mortality risk following hip fractures. Importantly, overall, rapid bone loss was associated with 44-77 % increased mortality risk after multiple variable adjustment.

CONCLUSION

Rapid bone loss was an independent predictor of post-fracture mortality risk in both women and men. The association of bone loss and post-fracture mortality was predominantly observed following vertebral fracture in both women and men and non-hip non-vertebral fracture in women. It remains to be determined whether bone loss is a marker or plays a role in the mortality associated with fractures.

Risk of subsequent fractures and mortality in elderly women and men with fragility fractures with and without osteoporotic bone density: the Dubbo Osteoporosis Epidemiology Study

Half of fragility fractures occur in individuals with nonosteoporotic BMD (BMD T-score > -2.5); however, there is no information on postfracture adverse events of subsequent fracture and mortality for different BMD levels. The objective of this work was to determine the risk and predictors of subsequent fracture and excess mortality following initial fracture according to BMD. The subjects were community-dwelling participants aged 60+ years from the Dubbo Osteoporosis Epidemiology Study with incident fractures followed from 1989 to 2011. The outcome measurements were as follows: risk of subsequent fracture and mortality according to BMD categorized as normal (T-score < -1), osteopenia (T-score ≤ -1 and > -2.5), and osteoporosis (T-score ≤ -2.5). There were 528 low-trauma fractures in women and 187 in men. Of these, 12% occurred in individuals with normal BMD (38 women, 50 men) and 42% in individuals with osteopenia (221 women, 76 men). The relative risk (RR) of subsequent fracture was >2.0-fold for all levels of BMD (normal BMD: 2.0 [1.2 to 3.3] for women and 2.1 [1.2 to 3.8] for men; osteopenia: 2.1 [1.7 to 2.6] for women and 2.5 [1.6 to 4.1] for men; and osteoporosis 3.2 [2.7 to 3.9] for women and 2.1 [1.4 to 3.1] for men. The likelihood of falling and reduced quadriceps strength contributed to subsequent fracture risk in women with normal BMD. By contrast with subsequent fracture risk, postfracture mortality was increased particularly in individuals with low BMD (age-adjusted standardized mortality ratio [SMR] for osteopenia 1.3 [1.1 to 1.7] and 2.2 [1.7 to 2.9] for women and men, respectively, and osteoporosis 1.7 [1.5 to 2.0] and 2.7 [2.0 to 3.6] for women and men, respectively). This study demonstrates the high burden of subsequent fracture in individuals with normal BMD and osteopenia, and excess mortality particularly for those with osteopenia (and osteoporosis). These findings highlight the importance of these fractures and underscore the gap in evidence for benefit of antiosteoporotic treatment for fragility fracture, in those with only mildly low BMD.

External validation of the Garvan nomograms for predicting absolute fracture risk: the Tromsø study

Background

Absolute risk estimation is a preferred approach for assessing fracture risk and treatment decision making. This study aimed to evaluate and validate the predictive performance of the Garvan Fracture Risk Calculator in a Norwegian cohort.

Methods

The analysis included 1637 women and 1355 aged 60+ years from the Tromsø study. All incident fragility fractures between 2001 and 2009 were registered. The predicted probabilities of non-vertebral osteoporotic and hip fractures were determined using models with and without BMD. The discrimination and calibration of the models were assessed. Reclassification analysis was used to compare the models performance.

Results

The incidence of osteoporotic and hip fracture was 31.5 and 8.6 per 1000 population in women, respectively; in men the corresponding incidence was 12.2 and 5.1. The predicted 5-year and 10-year probability of fractures was consistently higher in the fracture group than the non-fracture group for all models. The 10-year predicted probabilities of hip fracture in those with fracture was 2.8 (women) to 3.1 times (men) higher than those without fracture. There was a close agreement between predicted and observed risk in both sexes and up to the fifth quintile. Among those in the highest quintile of risk, the models over-estimated the risk of fracture. Models with BMD performed better than models with body weight in correct classification of risk in individuals with and without fracture. The overall net decrease in reclassification of the model with weight compared to the model with BMD was 10.6% (p = 0.008) in women and 17.2% (p = 0.001) in men for osteoporotic fractures, and 13.3% (p = 0.07) in women and 17.5% (p = 0.09) in men for hip fracture.

Conclusions

The Garvan Fracture Risk Calculator is valid and clinically useful in identifying individuals at high risk of fracture. The models with BMD performed better than those with body weight in fracture risk prediction.

The impact of nonhip nonvertebral fractures in elderly women and men

CONTEXT

Nonhip nonvertebral fractures represent half of all osteoporotic fractures; however, their contribution to the burden of refracture and premature mortality is unclear.

OBJECTIVES

To examine the risk and burden of subsequent fracture and mortality associated with an initial nonhip nonvertebral fracture.

SETTING AND PARTICIPANTS

This is a prospective cohort from the Dubbo Osteoporosis Epidemiology Study, 1989-2010 of community dwelling participants aged 60+ with incident fractures.

OUTCOME MEASURES

Relative risk of all subsequent fractures and age-adjusted standardized mortality ratios were calculated according to initial fracture type. The total burden of adverse events was assessed using competing risk models with four potential outcomes: mortality after initial fracture, mortality after subsequent fracture, subsequent fracture and alive, or event-free.

RESULTS

Of the 952 fractures in women and 343 in men, over half were nonhip nonvertebral fractures (486 in women and 173 in men). Nonhip nonvertebral fractures were associated with increased risk of any subsequent fracture (1.95 [1.67-2.27] for women and 2.47 [1.82-3.35] for men), hip refracture (2.11 [1.04-4.28] for women and 2.63 [1.35-5.13] for men), and vertebral refracture (1.89 [1.43-2.48] for women and 2.13 [1.20-3.79] for men). More importantly, nonhip nonvertebral fractures were associated overall with 20% excess mortality for the first 5 years postfracture, of which approximately half were due to initial fracture and the remaining due to subsequent fractures. Proximal fractures were associated with increased mortality risk per se, whereas distal fractures were associated with increased mortality risk only in the group who sustained subsequent fractures.

CONCLUSION

Nonhip nonvertebral fractures are associated with significant risk of subsequent fracture including hip and vertebral refracture, and premature mortality. Due to their high prevalence, about half of all subsequent fractures and a quarter of all fracture-related excess mortality were attributable to nonhip nonvertebral fracture. Thus nonhip nonvertebral fracture warrants early investigation and appropriate intervention.

Compound risk of high mortality following osteoporotic fracture and refracture in elderly women and men

After fracture there is increased risk of refracture and premature mortality. These outcomes, particularly premature mortality following refracture, have not previously been studied together to understand overall mortality risk. This study examined the long-term cumulative incidence of subsequent fracture and total mortality with mortality calculated as a compound risk and separated according to initial and refracture. Community-dwelling participants aged 60+ years from Dubbo Osteoporosis Epidemiology Study with incident fractures, followed prospectively for further fractures and deaths from 1989 to 2010. Subsequent fracture and mortality ascertained using cumulative incidence competing risk models allowing four possible outcomes: death without refracture; death following refracture; refracture but alive, and event-free. There were 952 women and 343 men with incident fracture. Within 5 years following initial fracture, 24% women and 20% men refractured; and 26% women and 37% men died without refracture. Of those who refractured, a further 50% of women and 75% of men died, so that total 5-year mortality was 39% in women and 51% in men. Excess mortality was 24% in women and 27% in men. Although mortality following refracture occurred predominantly in the first 5 years post-initial fracture, total mortality (post-initial and refracture) was elevated for 10 years. Most of the 5-year to 10-year excess mortality was associated with refracture. The long-term (>10 years) refracture rate was reduced, particularly in the elderly as a result of their high mortality rate. The 30% alive beyond 10 years postfracture were at low risk of further adverse outcomes. Refractures contribute substantially to overall mortality associated with fracture. The majority of the mortality and refractures occurred in the first 5 years following the initial fracture. However, excess mortality was observed for up to 10 years postfracture, predominantly related to that after refracture.

Osteoporosis medication and reduced mortality risk in elderly women and men

CONTEXT

Osteoporotic fractures are associated with premature mortality. Antiresorptive treatment reduces refracture but mortality reduction is unclear.

OBJECTIVE

The objective of the study was to examine the effect of osteoporosis treatment [bisphosphonates (BP), hormone therapy (HT), and calcium ± vitamin D only (CaD)] on mortality risk.

DESIGN

This was a prospective cohort study (April 1989 to May 2007).

SETTING

The study was conducted with community-dwelling elderly (aged 60+ yr) subjects in Dubbo, a semiurban city, Australia.

SUBJECTS

Subjects included 1223 and 819 women and men in the Dubbo Osteoporosis Epidemiology Study.

MAIN OUTCOME MEASURE

Mortality according to treatment group was recorded.

RESULTS

There were 325 (BP, n = 106; HT, n = 77; CaD, n = 142) women and 37 men (BP, n = 15; CaD, n = 22) on treatment. In women, mortality rates were lower with BP 0.8/100 person-years (0.4, 1.4) and HT 1.2/100 person-years (0.7, 2.1) but not CaD 3.2/100 person-years (2.5, 4.1) vs. no treatment 3.5/100 person-years (3.1, 3.8). Accounting for age, fracture occurrence, comorbidities, quadriceps strength, and bone mineral density, mortality risk remained lower for women on BP [hazard ratio (HR) 0.3 (0.2, 0.6)] but not HT [HR 0.8 (0.4, 1.8)]. For 429 women with fractures, mortality risk was still reduced in the BP group [adjusted HR 0.3 (0.2, 0.7)], not accounted for by a reduction in subsequent fractures. In men, lower mortality rates were observed with BP but not CaD [BP 1.0/100 person-years (0.3, 3.9) and CaD 3.1/100 person-years (1.5, 6.6) vs. no treatment 4.3/100 person-years (3.9, 4.8)]. After adjustment, mortality was similar, although not significant [HR 0.5 (0.1, 2.0)].

CONCLUSIONS

Osteoporosis therapy appears to reduce mortality risk in women and possibly men.

Mortality risk associated with low-trauma osteoporotic fracture and subsequent fracture in men and women

CONTEXT

There are few data on long-term mortality following osteoporotic fracture and fewer following subsequent fracture.

OBJECTIVES

To examine long-term mortality risk in women and men following all osteoporotic fractures and to assess the association of subsequent fracture with that risk.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort from the Dubbo Osteoporosis Epidemiology Study of community-dwelling women and men aged 60 years and older from Dubbo, Australia, who sustained a fracture between April 1989 and May 2007.

MAIN OUTCOME MEASURES

Age- and sex-specific standardized mortality ratios (SMRs) compared with the overall Dubbo population for hip, vertebral, major, and minor fractures.

RESULTS

In women, there were 952 low-trauma fractures followed by 461 deaths, and in men, 343 fractures were followed by 197 deaths. Age-adjusted SMRs were increased following hip fractures (SMRs, 2.43 [95% confidence interval [CI], 2.02-2.93] and 3.51 [95% CI, 2.65-4.66]), vertebral fractures (SMRs, 1.82 [95% CI, 1.52-2.17] and 2.12 [95% CI, 1.66-2.72]), major fractures (SMRs, 1.65 [95% CI, 1.31-2.08] and 1.70 [95% CI, 1.23-2.36]), and minor fractures (SMRs, 1.42 [95% CI, 1.19-1.70] and 1.33 [95% CI, 0.99-1.80]) for both women and men, respectively. Mortality was increased for all ages for all fractures except minor fractures for which increased mortality was only apparent for those older than 75 years. Increased mortality risk persisted for 5 years for all fractures and up to 10 years for hip fractures. Increases in absolute mortality that were above expected, for 5 years after fracture, ranged from 1.3 to 13.2 per 100 person-years in women and from 2.7 to 22.3 per 100 person-years in men, depending on fracture type. Subsequent fracture was associated with an increased mortality hazard ratio of 1.91 (95% CI, 1.54-2.37) in women and 2.99 (95% CI, 2.11-4.24) in men. Mortality risk following a subsequent fracture then declined but beyond 5 years still remained higher than in the general population (SMR, 1.41 [95% CI, 1.01-1.97] and SMR, 1.78 [95% CI, 0.96-3.31] for women and men, respectively). Predictors of mortality after any fragility fracture for both men and women included age, quadriceps weakness, and subsequent fracture but not comorbidities. Low bone mineral density, having smoked, and sway were also predictors for women and less physical activity for men.

CONCLUSIONS

In a sample of older women and men, all low-trauma fractures were associated with increased mortality risk for 5 to 10 years. Subsequent fracture was associated with increased mortality risk for an additional 5 years.

Successful direct intervention for osteoporosis in patients with minimal trauma fractures

In this study, we offered osteoporosis investigation and treatment directly to patients at out-patient fracture clinics shortly after they sustained minimal trauma fractures. We achieved long-term compliance to the recommended investigation and treatment in 80% of patients. This approach is much more successful than previous interventions.

INTRODUCTION

Osteoporosis remains under-treated in minimal-trauma fracture subjects. The aim of this study was to determine if direct intervention at orthopaedic fracture clinics would improve post-fracture management in these subjects.

METHODS

From March 2004 to March 2006, 155 consecutive minimal-trauma fracture subjects (mean age 64.0 +/- 17.6) attending fracture clinics at St. Vincent's Hospital, Sydney, had a specific medical assessment, following which they were recommended BMD and laboratory testing. Treatment recommendations were given after review of investigations with further follow-up at a median of 8.6 months following therapy. Comparison of outcomes was made with a similar group of patients given written information 2 years prior.

RESULTS

At baseline, 47% of patients had prior fractures, but only 26% had had BMD screening. Twenty-one percent were on anti-resorptive therapy, and 15% were on calcium/vitamin D. Following intervention, 83% had a BMD and of these, 68% had a T-score < -1.0. Of treatment naïve patients, 44% were recommended anti-resorptive therapy and 56% were recommended calcium/vitamin D. Compliance was 80% for anti-resorptive and 76% for calcium/vitamin D. Female gender and lower BMD were predictors of compliance.

CONCLUSION

Compared with information-based intervention, direct intervention improved management two to fivefold, maintaining long-term treatment in 90% of osteoporotic and 73% of osteopenic subjects requiring therapy.