Eugene McCloskey

A meta-analysis of prior corticosteroid use and fracture risk

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

Smoking and fracture risk: a meta-analysis.

Smoking is widely considered a risk factor for future fracture. The aim of this study was to quantify this risk on an international basis and to explore the relationship of this risk with age, sex and bone mineral density (BMD). We studied 59,232 men and women (74% female) from ten prospective cohorts comprising EVOS/EPOS, DOES, CaMos, Rochester, Sheffield, Rotterdam, Kuopio, Hiroshima and two cohorts from Gothenburg. Cohorts were followed for a total of 250,000 person-years. The effect of current or past smoking, on the risk of any fracture, any osteoporotic fracture and hip fracture alone was examined using a Poisson model for each sex from each cohort. Covariates examined were age, sex and BMD. The results of the different studies were merged using the weighted β-coefficients. Current smoking was associated with a significantly increased risk of any fracture compared to non-smokers (RR=1.25; 95% Confidence Interval (CI)=1.15–1.36). Risk ratio (RR) was adjusted marginally downward when account was taken of BMD, but it remained significantly increased (RR=1.13). For an osteoporotic fracture, the risk was marginally higher (RR=1.29; 95% CI=1.13–1.28). The highest risk was observed for hip fracture (RR=1.84; 95% CI=1.52–2.22), but this was also somewhat lower after adjustment for BMD (RR=1.60; 95% CI=1.27–2.02). Risk ratios were significantly higher in men than in women for all fractures and for osteoporotic fractures, but not for hip fracture. Low BMD accounted for only 23% of the smoking-related risk of hip fracture. Adjustment for body mass index had a small downward effect on risk for all fracture outcomes. For osteoporotic fracture, the risk ratio increased with age, but decreased with age for hip fracture. A smoking history was associated with a significantly increased risk of fracture compared with individuals with no smoking history, but the risk ratios were lower than for current smoking. We conclude that a history of smoking results in fracture risk that is substantially greater than that explained by measurement of BMD. Its validation on an international basis permits the use of this risk factor in case finding strategies.

A reference standard for the description of osteoporosis

In 1994, the World Health Organization published diagnostic criteria for osteoporosis. Since then, many new technologies have been developed for the measurement of bone mineral at multiple skeletal sites. The information provided by each assessment will describe the clinical characteristics, fracture risk and epidemiology of osteoporosis differently. Against this background, there is a need for a reference standard for describing osteoporosis. In the absence of a true gold standard, this paper proposes that the reference standard should be based on bone mineral density (BMD) measurement made at the femoral neck with dual-energy X-ray absorptiometry (DXA). This site has been the most extensively validated, and provides a gradient of fracture risk as high as or higher than that of many other techniques. The recommended reference range is the NHANES III reference database for femoral neck measurements in women aged 20-29 years. A similar cut-off value for femoral neck BMD that is used to define osteoporosis in women can be used for the diagnosis of osteoporosis in men - namely, a value for BMD 2.5 SD or more below the average for young adult women. The adoption of DXA as a reference standard provides a platform on which the performance characteristics of less well established and new methodologies can be compared.

Double-blind controlled trial of oral clodronate in patients with bone metastases from breast cancer.

PURPOSE Osteolytic metastases often give rise to hypercalcemia, fracture, and bone pain, and occur commonly in patients with recurrent breast cancer. We assessed the bisphosphonate, clodronate, which has proven to be a useful treatment for hypercalcemia and may be a potent inhibitor of tumor-induced osteolysis, for its effect on reducing the osseous complications of metastatic breast cancer. PATIENTS AND METHODS We studied 173 patients with bone metastases due to breast cancer in a randomized, double-blind, placebo-controlled trial of oral clodronate 1,600 mg/d (85 patients) compared with an identical placebo (88 patients). RESULTS The patients in each wing were comparable in their clinical, radiologic, and biochemical characteristics at trial entry. In patients who received clodronate, there was a significant reduction compared with placebo in the total number of hypercalcemic episodes (28 v 52; P < .01), in the number of terminal hypercalcemic episodes (seven v 17; P < .05), in the incidence of vertebral fractures (84 v 124 per 100 patient-years; P < .025), and in the rate of vertebral deformity (168 v 252 per 100 patient-years; P < .001). The combined rate of all morbid skeletal events was significantly reduced (218.6 v 304.8 per 100 patient-years; P < .001). Trends were seen in favor of clodronate for nonvertebral fracture rates and radiotherapy requirements for bone pain (particularly spinal pain). No significant survival differences and no significant differences in side effects were observed between the two groups. CONCLUSIONS These findings indicate that oral clodronate has a beneficial effect on the skeletal morbidity associated with breast cancer and should be considered as antiosteolytic therapy in affected patients. It deserves further investigation as an adjuvant therapy in operable breast cancer and in patients with nonosseous recurrence who are at high risk for bone metastases.

The assessment of vertebral deformity: A method for use in population studies and clinical trials

The absence of specific criteria for the definition of vertebral fracture has major implications for assessing the apparent prevalence and incidence of vertebral deformity. Also, little is known of the effect of using different criteria for new vertebral fractures in clinical studies. We therefore developed radiological criteria for vertebral fracture in women for assessing both the prevalence and the incidence of vertebral osteoporosis in population and in prospective studies and compared these with several other published methods. Normal ranges for vertebral shape were obtained from radiographs in 100 women aged 45–50 years. These included ranges for the ratios of anterior/posterior, central/posterior and posterior/predicted posterior vertebral heights from T4 to L5. The predicted posterior height was calculated from adjacent vertebrae. In contrast to other methods, our definition of fracture required the fulfilment of two criteria at each vertebral site, and was associated with a lower apparent prevalence of fracture in the control women due to a lower false positive rate. The prevalence and incidence of vertebral deformity using different criteria were then compared in a series of women with skeletal metastases from breast cancer in whom radiographs were obtained 6 months apart. The prevalence of vertebral deformity and the specificity for deformity varied markedly with differing criteria. Using a cut-off of 3 standard deviations the prevalence of vertebral deformity in the women with breast cancer was 46%. Using other methods, the prevalences of deformity ranged from 33% to 74%. Over a 6-month interval 25% of patients with breast cancer sustained 61 deformities using our method, of which only 8% resulted from errors in reproducibility. The number of patients sustaining new deformities was increased twofold when assessed by other methods (45%–53%), but errors of reproducibility may have accounted for 21% of the new deformities. The magnitude and distribution of these errors have important implications for the apparent therapeutic efficacy of agents in clinical trials of osteoporosis. The rapid semi-automated technique for assessing vertebral deformities on lateral spine radiographs that we have developed has a high specificity, and reduces the impact of errors of reproducibility on estimates of prevalence and incidence. The method should prove a value in assessing vertebral deformity both in population studies and in prospective clinical trials.

A systematic review of hip fracture incidence and probability of fracture worldwide.

SummaryThe country-specific risk of hip fracture and the 10-year probability of a major osteoporotic fracture were determined on a worldwide basis from a systematic review of literature. There was a greater than 10-fold variation in hip fracture risk and fracture probability between countries.IntroductionThe present study aimed to update the available information base available on the heterogeneity in the risk of hip fracture on a worldwide basis. An additional aim was to document variations in major fracture probability as determined from the available FRAX models.MethodsStudies on hip fracture risk were identified from 1950 to November 2011 by a Medline OVID search. Evaluable studies in each country were reviewed for quality and representativeness and a study (studies) chosen to represent that country. Age-specific incidence rates were age-standardised to the world population in 2010 in men, women and both sexes combined. The 10-year probability of a major osteoporotic fracture for a specific clinical scenario was computed in those countries for which a FRAX model was available.ResultsFollowing quality evaluation, age-standardised rates of hip fracture were available for 63 countries and 45 FRAX models available in 40 countries to determine fracture probability. There was a greater than 10-fold variation in hip fracture risk and fracture probability between countries.ConclusionsWorldwide, there are marked variations in hip fracture rates and in the 10-year probability of major osteoporotic fractures. The variation is sufficiently large that these cannot be explained by the often multiple sources of error in the ascertainment of cases or the catchment population. Understanding the reasons for this heterogeneity may lead to global strategies for the prevention of fractures.

FRAX and its applications to clinical practice

The introduction of the WHO FRAX algorithms has facilitated the assessment of fracture risk on the basis of fracture probability. FRAX integrates the influence of several well validated risk factors for fracture with or without the use of BMD. Its use in fracture risk prediction poses challenges for patient assessment, the development of practice guidelines, the evaluation of drug efficacy and reimbursement, as well as for health economics which are the topics outlined in this review.

Randomized, placebo-controlled trial of clodronate in patients with primary operable breast cancer.

PURPOSE The development of bone metastases depends on tumor-induced osteoclastic resorption of bone, which may be inhibited by the antiosteolytic bisphosphonate clodronate. Given to patients with primary breast cancer, clodronate might reduce the subsequent incidence of bone metastases. PATIENTS AND METHODS This double-blind, multicenter trial accrued 1,069 assessable patients with operable breast cancer between 1989 and 1995. All patients received surgery, radiotherapy, chemotherapy, and tamoxifen as required. Patients were randomized to receive oral clodronate 1,600 mg/d or a placebo for 2 years starting within 6 months of primary treatment. The primary end point was relapse in bone, analyzed on an intent-to-treat basis, during the medication period and during the total follow-up period (median follow-up, 2,007 days). Secondary end points were relapse in other sites, mortality, and toxicity. RESULTS During the total follow-up period, there was a nonsignificant reduction in occurrence of bone metastases (clodronate, n = 63; placebo, n = 80; hazards ratio [HR], 0.77; 95% confidence interval [CI], 0.56 to 1.08; P =.127). During the medication period there was a significant reduction in the occurrence of bone metastases (clodronate, n = 12; placebo, n = 28; HR, 0.44; 95% CI, 0.22 to 0.86; P =.016). The occurrence of nonosseous metastases was similar (clodronate, n = 112; placebo, n = 128; P =.257), but there was a significant reduction in mortality (clodronate, n = 98; placebo, n = 129; P =.047) during the total follow-up period. CONCLUSION Clodronate, given to patients with primary operable breast cancer, may reduce the occurrence of bone metastases, although this reduction was only significant during this medication period. There was a significant reduction in mortality.

Trabecular bone score: a noninvasive analytical method based upon the DXA image.

The trabecular bone score (TBS) is a gray‐level textural metric that can be extracted from the two‐dimensional lumbar spine dual‐energy X‐ray absorptiometry (DXA) image. TBS is related to bone microarchitecture and provides skeletal information that is not captured from the standard bone mineral density (BMD) measurement. Based on experimental variograms of the projected DXA image, TBS has the potential to discern differences between DXA scans that show similar BMD measurements. An elevated TBS value correlates with better skeletal microstructure; a low TBS value correlates with weaker skeletal microstructure. Lumbar spine TBS has been evaluated in cross‐sectional and longitudinal studies. The following conclusions are based upon publications reviewed in this article: 1) TBS gives lower values in postmenopausal women and in men with previous fragility fractures than their nonfractured counterparts; 2) TBS is complementary to data available by lumbar spine DXA measurements; 3) TBS results are lower in women who have sustained a fragility fracture but in whom DXA does not indicate osteoporosis or even osteopenia; 4) TBS predicts fracture risk as well as lumbar spine BMD measurements in postmenopausal women; 5) efficacious therapies for osteoporosis differ in the extent to which they influence the TBS; 6) TBS is associated with fracture risk in individuals with conditions related to reduced bone mass or bone quality. Based on these data, lumbar spine TBS holds promise as an emerging technology that could well become a valuable clinical tool in the diagnosis of osteoporosis and in fracture risk assessment.

Assessment of fracture risk.

Fractures are a common complication of osteoporosis. Although osteoporosis is defined by bone mineral density at the femoral neck, other sites and validated techniques can be used for fracture prediction. Several clinical risk factors contribute to fracture risk independently of BMD. These include age, prior fragility fracture, smoking, excess alcohol, family history of hip fracture, rheumatoid arthritis and the use of oral glucocorticoids. These risk factors in conjunction with BMD can be integrated to provide estimates of fracture probability using the FRAX tool. Fracture probability rather than BMD alone can be used to fashion strategies for the assessment and treatment of osteoporosis.