Meghan G. Donaldson

Association of BMD and FRAX score with risk of fracture in older adults with type 2 diabetes.

CONTEXT Type 2 diabetes mellitus (DM) is associated with higher bone mineral density (BMD) and paradoxically with increased fracture risk. It is not known if low BMD, central to fracture prediction in older adults, identifies fracture risk in patients with DM. OBJECTIVE To determine if femoral neck BMD T score and the World Health Organization Fracture Risk Algorithm (FRAX) score are associated with hip and nonspine fracture risk in older adults with type 2 DM. DESIGN, SETTING, AND PARTICIPANTS Data from 3 prospective observational studies with adjudicated fracture outcomes (Study of Osteoporotic Fractures [December 1998-July 2008]; Osteoporotic Fractures in Men Study [March 2000-March 2009]; and Health, Aging, and Body Composition study [April 1997-June 2007]) were analyzed in older community-dwelling adults (9449 women and 7436 men) in the United States. MAIN OUTCOME MEASURE Self-reported incident fractures, which were verified by radiology reports. RESULTS Of 770 women with DM, 84 experienced a hip fracture and 262 a nonspine fracture during a mean (SD) follow-up of 12.6 (5.3) years. Of 1199 men with DM, 32 experienced a hip fracture and 133 a nonspine fracture during a mean (SD) follow-up of 7.5 (2.0) years. Age-adjusted hazard ratios (HRs) for 1-unit decrease in femoral neck BMD T score in women with DM were 1.88 (95% confidence interval [CI], 1.43-2.48) for hip fracture and 1.52 (95% CI, 1.31-1.75) for nonspine fracture, and in men with DM were 5.71 (95% CI, 3.42-9.53) for hip fracture and 2.17 (95% CI, 1.75-2.69) for nonspine fracture. The FRAX score was also associated with fracture risk in participants with DM (HRs for 1-unit increase in FRAX hip fracture score, 1.05; 95% CI, 1.03-1.07, for women with DM and 1.16; 95% CI, 1.07-1.27, for men with DM; HRs for 1-unit increase in FRAX osteoporotic fracture score, 1.04; 95% CI, 1.02-1.05, for women with DM and 1.09; 95% CI, 1.04-1.14, for men with DM). However, for a given T score and age or for a given FRAX score, participants with DM had a higher fracture risk than those without DM. For a similar fracture risk, participants with DM had a higher T score than participants without DM. For hip fracture, the estimated mean difference in T score for women was 0.59 (95% CI, 0.31-0.87) and for men was 0.38 (95% CI, 0.09-0.66). CONCLUSIONS Among older adults with type 2 DM, femoral neck BMD T score and FRAX score were associated with hip and nonspine fracture risk; however, in these patients compared with participants without DM, the fracture risk was higher for a given T score and age or for a given FRAX score.

Otago Home-Based Strength and Balance Retraining Improves Executive Functioning in Older Fallers : A Randomized Controlled Trial

OBJECTIVES: To primarily ascertain the effect of the Otago Exercise Program (OEP) on physiological falls risk, functional mobility, and executive functioning after 6 months in older adults with a recent history of falls and to ascertain the effect of the OEP on falls during a 1‐year follow‐up period.

A Comparison of Prediction Models for Fractures in Older Women: Is More Better

BACKGROUND A Web-based risk assessment tool (FRAX) using clinical risk factors with and without femoral neck bone mineral density (BMD) has been incorporated into clinical guidelines regarding treatment to prevent fractures. However, it is uncertain whether prediction with FRAX models is superior to that based on parsimonious models. METHODS We conducted a prospective cohort study in 6252 women 65 years or older to compare the value of FRAX models that include BMD with that of parsimonious models based on age and BMD alone for prediction of fractures. We also compared FRAX models without BMD with simple models based on age and fracture history alone. Fractures (hip, major osteoporotic [hip, clinical vertebral, wrist, or humerus], and any clinical fracture) were ascertained during 10 years of follow-up. Area under the curve (AUC) statistics from receiver operating characteristic curve analysis were compared between FRAX models and simple models. RESULTS The AUC comparisons showed no differences between FRAX models with BMD and simple models with age and BMD alone in discriminating hip (AUC, 0.75 for the FRAX model and 0.76 for the simple model; P = .26), major osteoporotic (AUC, 0.68 for the FRAX model and 0.69 for the simple model; P = .51), and clinical fracture (AUC, 0.64 for the FRAX model and 0.63 for the simple model; P = .16). Similarly, performance of parsimonious models containing age and fracture history alone was nearly identical to that of FRAX models without BMD. The proportion of women in each quartile of predicted risk who actually experienced a fracture outcome did not differ between FRAX and simple models (P > or = .16). CONCLUSION Simple models based on age and BMD alone or age and fracture history alone predicted 10-year risk of hip, major osteoporotic, and clinical fracture as well as more complex FRAX models.

Exercise and cognition in older adults: is there a role for resistance training programmes?

In recent years, there has been a strong interest in physical activity as a primary behavioural prevention strategy against cognitive decline. A number of large prospective cohort studies have highlighted the protective role of regular physical activity in lowering the risk of cognitive impairment and dementia. Most prospective intervention studies of exercise and cognition to date have focused on aerobic-based exercise training. These studies highlight that aerobic-based exercise training enhances both brain structure and function. However, it has been suggested that other types of exercise training, such as resistance training, may also benefit cognition. The purpose of this brief review is to examine the evidence regarding resistance training and cognitive benefits. Three recent randomised exercise trials involving resistance training among seniors provide evidence that resistance training may have cognitive benefits. Resistance training may prevent cognitive decline among seniors via mechanisms involving insulin-like growth factor I and homocysteine. A side benefit of resistance training, albeit a very important one, is its established role in reducing morbidity among seniors. Resistance training specifically moderates the development of sarcopenia. The multifactorial deleterious sequelae of sarcopenia include increased falls and fracture risk as well as physical disability. Thus, clinicians should consider encouraging their clients to undertake both aerobic-based exercise training and resistance training not only for “physical health” but also because of the almost certain benefits for “brain health”.

Results of a 10 week community based strength and balance training programme to reduce fall risk factors: a randomised controlled trial in 65–75 year old women with osteoporosis

Objective—To test the efficacy of a community based 10 week exercise intervention to reduce fall risk factors in women with osteoporosis. Methods—Static balance was measured by computerised dynamic posturography (Equitest), dynamic balance by timed figure of eight run, and knee extension strength by dynamometry. Subjects were randomised to exercise intervention (twice weekly Osteofit classes for 10 weeks) or control groups. Results—The outcome in 79 participants (39 exercise, 40 control) who were available for measurement 10 weeks after baseline measurement is reported. After confounding factors had been controlled for, the exercise group did not make significant gains compared with their control counterparts, although there were consistent trends toward greater improvement in all three primary outcome measures. Relative to the change in control subjects, the exercise group improved by 2.3% in static balance, 1.9% in dynamic balance, and 13.9% in knee extension strength. Conclusions—A 10 week community based physical activity intervention did not significantly reduce fall risk factors in women with osteoporosis. However, trends toward improvement in key independent risk factors for falling suggest that a study with greater power may show that these variables can be improved to a level that reaches statistical significance.

New criteria for female athlete triad syndrome

As osteoporosis is rare, should osteopenia be among the criteria for defining the female athlete triad syndrome? The American College of Sports Medicine (ACSM) has provided a great deal of impetus to educating healthcare providers, athletes, and the general public about the potential harm of a “serious syndrome consisting of disordered eating, amenorrhoea and osteoporosis”.1 We recognise and respect the importance of research and attention to this clinical problem and commend the ACSM on its contribution to date.2 To their credit, the authors of the most recent position stand acknowledged that there were no data reporting prevalence on this condition,3 and they encouraged further research. Since then, Mayo Clinic physiatrist Tamara Lauder4 has published two important papers showing a 0% prevalence of the female athlete triad (as defined by ACSM) despite 34% of this military population being at risk of disordered eating. Therefore we re-examined the prevalence of one component of the female athlete triad, osteoporosis, in studies of athletic women with menstrual disturbance. The syndrome can be no more prevalent than any one of its diagnostic criteria alone. Thus, if osteoporosis is only present in a small proportion of the population, then it follows that the female athlete triad can only be prevalent in an equally small, or smaller, proportion of that population. Because of the increasing public awareness of osteoporosis and its complications, medical practitioners must not use the term as a synonym for “low bone mass”.5 The current standard for measuring bone mass (bone mineral density; BMD) is by dual energy x ray absorptiometry, and since 1994 the term osteoporosis has had diagnostic criteria based on this technique.3, 6, 7 Osteoporosis is defined as BMD more than 2.5 standard deviations below the mean of young adults. The term osteopenia describes BMD …

Estimates of the proportion of older white men who would be recommended for pharmacologic treatment by the new US national osteoporosis foundation guidelines

The new US National Osteoporosis Foundations (NOFs) Clinicians Guide to Prevention and Treatment of Osteoporosis includes criteria for recommending pharmacologic treatment based on history of hip or vertebral fracture, femoral neck or spine bone mineral density (BMD) T‐scores of −2.5 or less, and presence of low bone mass at the femoral neck or spine plus a 10‐year risk of hip fracture of 3% or greater or of major osteoporotic fracture of 20% or greater. The proportion of men who would be recommended for treatment by these guidelines is not known. We applied the NOF criteria for treatment to men participating in the Osteoporotic Fractures in Men Study (MrOS). To determine how the MrOS population differs from the general US population of Caucasian men aged 65 years and older, we compared men in MrOS with men who participated in the National Health and Nutrition Examination Survey (NHANES) III on criteria included in the NOF treatment guidelines that were common to both cohorts. Compared with NHANES III, men in MrOS had higher femoral neck BMD values. Application of NOF guidelines to MrOS data estimated that at least 34% of US white men aged 65 years and older and 49% of those aged 75 years and older would be recommended for drug treatment. Application of the new NOF guidelines would result in recommending a very large proportion of white men in the United States for pharmacologic treatment of osteoporosis, for many of whom the efficacy of treatment is unknown.

FRAX and Risk of Vertebral Fractures: The Fracture Intervention Trial†

The validity of the WHO 10‐yr probability of major osteoporotic fracture model (FRAX) for prediction of vertebral fracture has not been tested. We analyzed how well FRAX for major osteoporotic fractures, with and without femoral neck BMD (FN BMD), predicted the risk of vertebral fracture. We also compared the predictive validity of FRAX, FN BMD, and prevalent vertebral fracture detected by radiographs at baseline alone or in combination to predict future vertebral fracture. We analyzed data from the placebo groups of FIT (3.8‐yr follow‐up, n = 3221) with ORs and areas under receiver operating characteristics (ROC) curves (AUC). FRAX with and without FN BMD predicted incident radiographic vertebral fracture. The AUC was significantly greater for FRAX with FN BMD (AUC = 0.71) than FRAX without FN BMD (AUC = 0.68; p = 0.002). Prevalent vertebral fracture plus age and FN BMD (AUC = 0.76) predicted incident radiographic vertebral fracture as well as a combination of prevalent vertebral fracture and FRAX with FN BMD (AUC = 0.75; p = 0.76). However, baseline vertebral fracture status plus age and FN BMD (AUC = 0.76) predicted incident radiographic vertebral fracture significantly better than FRAX with FN BMD (AUC = 0.71; p = 0.0017). FRAX for major osteoporotic fractures (with and without FN BMD) predicts vertebral fracture. However, once FN BMD and age are known, the eight additional risk factors in FRAX do not significantly improve the prediction of vertebral fracture. A combination of baseline radiographic vertebral fracture, FN BMD, and age is the strongest predictor of future vertebral fracture.

WHO absolute fracture risk models (FRAX): Do clinical risk factors improve fracture prediction in older women without osteoporosis?

Bone mineral density (BMD) is a strong predictor of fracture, yet most fractures occur in women without osteoporosis by BMD criteria. To improve fracture risk prediction, the World Health Organization recently developed a country‐specific fracture risk index of clinical risk factors (FRAX) that estimates 10‐year probabilities of hip and major osteoporotic fracture. Within differing baseline BMD categories, we evaluated 6252 women aged 65 or older in the Study of Osteoporotic Fractures using FRAX 10‐year probabilities of hip and major osteoporotic fracture (ie, hip, clinical spine, wrist, and humerus) compared with incidence of fractures over 10 years of follow‐up. Overall ability of FRAX to predict fracture risk based on initial BMD T‐score categories (normal, low bone mass, and osteoporosis) was evaluated with receiver‐operating‐characteristic (ROC) analyses using area under the curve (AUC). Over 10 years of follow‐up, 368 women incurred a hip fracture, and 1011 a major osteoporotic fracture. Women with low bone mass represented the majority (n = 3791, 61%); they developed many hip (n = 176, 48%) and major osteoporotic fractures (n = 569, 56%). Among women with normal and low bone mass, FRAX (including BMD) was an overall better predictor of hip fracture risk (AUC = 0.78 and 0.70, respectively) than major osteoporotic fractures (AUC = 0.64 and 0.62). Simpler models (eg, age + prior fracture) had similar AUCs to FRAX, including among women for whom primary prevention is sought (no prior fracture or osteoporosis by BMD). The FRAX and simpler models predict 10‐year risk of incident hip and major osteoporotic fractures in older US women with normal or low bone mass.

Osteoporosis screening in postmenopausal women 50 to 64 years old: Comparison of US preventive services task force strategy and two traditional strategies in the Women's Health Initiative

The US Preventive Services Task Force (USPSTF) recommends osteoporosis screening for women younger than 65 years whose 10‐year predicted risk of major osteoporotic fracture is ≥9.3%. For identifying screening candidates among women aged 50 to 64 years, it is uncertain how the USPSTF strategy compares with the Osteoporosis Self‐Assessment Tool (OST) and the Simple Calculated Osteoporosis Risk Estimate (SCORE). We examined data (1994 to 2012) from 5165 Womens Health Initiative participants aged 50 to 64 years. For the USPSTF (Fracture Risk Assessment Tool [FRAX] major fracture risk ≥9.3% calculated without bone mineral density [BMD]), OST (score <2), and SCORE (score >7) strategies, we assessed sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) to discriminate between those with and without femoral neck (FN) T‐score ≤−2.5. Sensitivity, specificity, and AUC for identifying FN T‐score ≤−2.5 were 34.1%, 85.8%, and 0.60 for USPSTF (FRAX); 74.0%, 70.8%, and 0.72 for SCORE; and 79.8%, 66.3%, and 0.73 for OST. The USPSTF strategy identified about one‐third of women aged 50 to 64 years with FN T‐scores ≤−2.5. Among women aged 50 to 64 years, the USPSTF strategy was modestly better than chance alone and inferior to conventional SCORE and OST strategies in discriminating between women with and without FN T‐score ≤−2.5.