Changes in secondary hyperparathyroidism-related biochemical parameters and medication use following parathyroidectomy.

BACKGROUND: Little is known about changes in parathyroid hormone (PTH), calcium and phosphorous levels after parathyroidectomy in hemodialysis patients. We studied the effects of parathyroidectomy on these biochemical values in a large cohort of patients receiving maintenance hemodialysis. METHODS: This retrospective cohort study included patients identified in both the United States Renal Data System and the database of a large dialysis organization who underwent parathyroidectomy in 2007-09, were aged ≥ 18 years, had Medicare Parts A and B as primary payer and had received hemodialysis for ≥ 1 year pre-parathyroidectomy. Descriptive statistics were calculated for continuous variables; categorical variables were used to characterize the population and evaluate monthly laboratory and medication use; median values were calculated for laboratory measures. RESULTS: Among 1402 parathyroidectomy patients, mean age was 48.9 years, 52.4% were males, 58.8% were African American and mean dialysis duration was 7.5 years. Median PTH levels increased over the year before parathyroidectomy from 1039 to 1661 pg/mL and decreased afterward to 98 pg/mL at 1 month; levels remained ≥ 897 pg/mL for 10% of patients. Median calcium levels fell from 9.6 mg/dL before to 7.9 mg/dL 1 month after parathyroidectomy; levels were ≤ 7.1 mg/dL for 25% and remained ≤ 7.2 mg/dL for the lowest 25% at 3 months. Median phosphorous level was 6.8 mg/dL immediately before parathyroidectomy, decreased to 3.8 mg/dL immediately after and reached 5.8 mg/dL at 1 year. CONCLUSIONS: While PTH levels dropped after parathyroidectomy for most patients, surgery was sometimes ineffective in reducing levels and sometimes led to over-suppression. Hypocalcemia could be profound and long lasting, suggesting the need for prolonged vigilance.

Co-trending of parathyroid hormone and phosphate in patients receiving hemodialysis.

AIM: The objective of this study was to examine the time-varying relationship of chronic kidney disease-mineral bone disorder (CKD-MBD) related biochemical parameters (parathyroid hormone (PTH), calcium, phosphate) over a 12-month period. MATERIAL AND METHODS: Using data from a large US provider of dialysis services from 2010 through 2012, we constructed a cohort of adult patients receiving in-center hemodialysis who had biochemical parameters measured at both baseline and 12 months of follow-up. We used descriptive statistics to assess the overall distributions of the biochemical parameters at both measurements, to examine how patients transitioned between categories for each biochemical parameter, and to evaluate how the biochemical parameters changed with respect to each other. RESULTS: Among the 132,087 patients included in our analyses, the cross-sectional distributions for the combined categories of 150 - < 300 and 300 - < 600 pg/mL for PTH between the two measurements remained unchanged (67% of patients). For calcium and phosphate, the distributions across all categories also remained largely unchanged. Considering within-patient changes over time. however, a majority (74%) of patients who initially had a PTH < 150 pg/mL transitioned to a higher category, while a majority (56%) of patients who initially had a PTH > 600 pg/mL transitioned to a lower category. We observed that phosphate values on average directly trended with PTH values over the follow-up period. CONCLUSION: We found that while calcium showed relatively little variation, parallel bidirectional variation in PTH and phosphate over time was quite common among adult patients receiving hemodialysis. Optimal control of phosphate is likely to be dependent not only on consistent adherence to dietary restrictions and phosphate binders, but may additionally rely on adequate and sustained control of PTH.

Facility-level CKD-MBD composite score and risk of adverse clinical outcomes among patients on hemodialysis.

BACKGROUND: Patients receiving hemodialysis with values outside of target levels for parathyroid hormone (PTH: 150-600 pg/mL), calcium (Ca: 8.4-10.2 mg/dL), and phosphate (P: 3.5-5.5 mg/dL) are at elevated morbidity and mortality risk. We examined whether patients receiving care in dialysis facilities where greater proportions of patients have at least two values out of target have a higher risk of adverse clinical outcomes. METHODS: The study cohort consisted of 39,085 prevalent hemodialysis patients in 1298 DaVita dialysis facilities as of September 1, 2009, followed from January 1, 2010, until an outcome, a censoring event, or December 31, 2010. We determined the quintile of the distribution across facilities of the proportion of patients with at least two of three parameters out of, or above, target over a 4-month baseline period. The primary composite outcome was cardiovascular hospitalization or death. Secondary outcomes included death, cardiovascular hospitalization, and parathyroidectomy. Poisson regression models were used to estimate the association of facility quintile with outcomes. RESULTS: Facility quintile was associated with a 7 % increased risk of cardiovascular hospitalization or death (quintile 5 versus 1, RR 1.07, 95 % CI 1.01-1.13) using the out-of-target measure of exposure and a 12 % increased risk (RR 1.12, 95 % CI 1.06-1.19) using the above-target measure. No association was seen for death using either measure. Patients in facility quintiles 3-5 (versus 1) were at increased parathyroidectomy risk (RR ranged from 2.05, 95 % CI 1.10-3.82, for quintile 3 to 2.73, 95 % CI 1.50-4.98, for quintile 5). CONCLUSIONS: Facility level analysis of a large prevalent sample of US patients on hemodialysis demonstrates that patients in facilities with the least control of PTH, Ca, and P had the greatest risk of parathyroidectomy or the combination of cardiovascular hospitalization or death.

Facility Dialysate Calcium Practices and Clinical Outcomes Among Patients Receiving Hemodialysis: A Retrospective Observational Study.

BACKGROUND: Some US dialysis facilities have reduced default dialysate calcium concentrations from 2.5 mEq/L to lower levels. There has been no rigorous systematic examination of the effects of such a reduction on clinical and biochemical outcomes. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Medicare-eligible patients who received in-center hemodialysis at a large dialysis organization in January 2008 to December 2010. PREDICTOR: Facility conversion from predominant use (≥75% patients) of 2.50-mEq/L dialysate calcium to predominant use of lower dialysate calcium concentrations versus maintenance of predominant use of 2.50-mEq/L dialysate calcium. OUTCOMES: All-cause and cause-specific mortality and hospitalization, laboratory markers of metabolic bone disease, and drug utilization. MEASUREMENTS: Hierarchical mixed linear and Poisson models were fit to compare pre- to postconversion differences in outcomes between converter and matched control facilities. Results, expressed as relative rate ratios (RRRs) and delta-delta (change in mean values), were estimated for early (months 0-2) and late (months 3-12) postconversion to allow for possible latent effects. RESULTS: Facility conversion was associated with greater rates of hospitalization for heart failure exacerbation (late RRR, 1.27 [95% CI, 1.06-1.51]), hypocalcemia (early RRR, 1.19 [95% CI, 1.05-1.35]; late RRR, 1.39 [95% CI, 1.20-1.60]), and intradialytic hypotension (early RRR, 1.07 [95% CI, 1.02-1.11]; late RRR, 1.05 [95% CI, 1.01-1.10]), but no differences were observed for all-cause mortality or hospitalization rates. Facility conversion was also associated with comparative temporal decreases in serum calcium level, increases in serum phosphate and parathyroid hormone levels, and increases in use of phosphate binders, vitamin D, and calcimimetics. LIMITATIONS: Possible residual confounding, generalizability beyond Medicare patients uncertain. CONCLUSIONS: There are potential safety concerns associated with the default use of dialysate calcium concentrations < 2.50 mEq/L, as well as biochemical evidence of poorer disease control despite associated greater medication use. Individualization of dialysate calcium concentration rather than predominant use of dialysate calcium concentrations < 2.50 mEq/L should be considered.

Refining the definition of clinically important mineral and bone disorder in hemodialysis patients.

BACKGROUND: It is important to identify an easily defined subset of patients at increased risk of adverse clinical outcomes associated with mineral and bone disorder (MBD) biomarkers (parathyroid hormone, calcium and phosphate). METHODS: Observational cohort study of 26 221 prevalent hemodialysis patients in Davita clinics as of 31 August 2005 and followed up until 31 December 2006 (16 months). Predictors were 12 possible definitions of 'clinically important' MBD based on all 3 biomarkers, and 18 alternative definitions based on only 1 or 2 biomarkers. Events were death alone and a composite of cardiovascular hospitalization or death. Excess events were calculated based on a multivariate Cox model using 5224 patients in target for all MBD biomarkers and applied to 20 997 patients out of target for at least one biomarker. Excess events attributable to MBD were estimated by subtracting the multivariate model-derived predicted number from the actual number. Outcomes were the proportion of excess events attributable to MBD captured by each definition (threshold ≥70%) and the reduction in the population size considered to have clinically important MBD (threshold ≥30%). The excess fraction was excess events divided by actual events. RESULTS: Patients with more biochemical markers out of target tended to be younger, black and have longer times since starting dialysis. The excess fraction associated with MBD ranged from ∼10 to 26% depending on the clinical endpoint and definition. The only definition to meet the thresholds required at least two of the three MBD biomarkers to be out of target (high or low). It captured 82% of excess composite endpoints and 74% of excess deaths and reduced the at-risk population by 46%. CONCLUSIONS: Patients with at least two of three MBD biomarkers out of target represent a subgroup of patients at elevated risk of adverse clinical events.

Management of serum calcium reductions among patients on hemodialysis following cinacalcet initiation.

PURPOSE: Cinacalcet is indicated for treatment of secondary hyperparathyroidism in patients receiving hemodialysis. Cinacalcet reduces serum calcium concentrations by decreasing parathyroid hormone secretion, but the frequency and degree of calcium reduction following cinacalcet initiation, subsequent physician response, and ultimate calcium recovery in clinical practice are not well described. METHODS: Patients receiving hemodialysis at a large dialysis organization who enrolled in the organization's prescription benefits service and initiated cinacalcet at serum calcium ≥8.4 mg/dL were studied (N = 13 723). Patients were categorized by whether they experienced a reduction in calcium to <8.4 mg/dL and to what level (<7.5, 7.5-7.9, and 8.0-8.3 mg/dL). Baseline characteristics, frequency of subsequent intervention, and calcium recovery were compared. RESULTS: Of those who experienced a reduction in calcium to <8.4 mg/dL (n = 6437 [46.9%]), 6.6% had calcium <7.5 mg/dL and 24.5% had calcium 7.5-7.9 mg/dL, while the majority (68.9%) had a level of 8-8.3 mg/dL. Higher baseline parathyroid hormone and alkaline phosphatase were associated with lower resultant calcium. Among patients with calcium reductions, 45.6-63.5% received one or more directed clinical therapeutic responses, including 15.6-28.4% for whom cinacalcet was discontinued; the majority of patients recovered to calcium ≥8.4 mg/dL within 90 days of first detection. Only modest differences in recovery were noted between patients who did and did not receive any therapeutic response and patients who did and did not discontinue cinacalcet. CONCLUSION: Serum calcium reductions following cinacalcet initiation were common; declines <7.5 mg/dL were infrequent. Calcium recovery occurred in the majority of patients, with or without therapeutic intervention.

Dynamics of cinacalcet use and biochemical control in hemodialysis patients: a retrospective New-user cohort design.

BACKGROUND: Cinacalcet is used to treat secondary hyperparathyroidism among hemodialysis patients. Large-scale epidemiologic studies describing patterns of cinacalcet use, effects on parathyroid hormone (PTH), calcium, and phosphorous levels, and predictors of discontinuation have not been previously reported. METHODS: This retrospective cohort study used a clinical database of a large U.S. dialysis provider (2007-2010) merged with administrative data from the United States Renal Data System. Among new users of cinacalcet with Medicare coverage, trends in PTH, calcium, and phosphorus were measured in 30-day intervals following cinacalcet initiation. RESULTS: Seventeen thousand seven hundred sixty-three eligible initiators contributed 111,047 30-day follow-up intervals. Of these, 56 % discontinued cinacalcet by month 4. Of those discontinuing, 76.3 % reinitiated. Mean values of PTH, calcium, and phosphorus decreased to recommended levels within 4 months following initiation. Proximal PTH levels < 150 pg/mL were associated with discontinuation: HR = 1.23 (95 % CI: 1.12, 1.36), whereas low calcium (< 7.5 mg/dL) was suggestive of an association, HR = 1.09 (95 % CI 0.91, 1.32). Being in the Part D gap period increased discontinuation risk: HR = 1.09 (95 % CI: 1.03, 1.16). Low-income subsidy status decreased discontinuation risk: HR = 0.77 (95 % CI 0.69, 0.86). Predictors of reinitiation included low-income subsidy, HR = 1.32 (95 % CI 1.22, 1.43); higher albumin level, HR = 1.23 (95 % CI 1.10, 1.36) and higher calcium level, HR = 1.26 (95 % CI 1.19, 1.33). CONCLUSIONS: Substantial and expected declines in laboratory values occurred following cinacalcet initiation. Early discontinuation and reinitiation of cinacalcet were common and may have occurred for clinical and economic reasons.

Patient-related risk factors for fracture-healing complications in the United Kingdom General Practice Research Database.

BACKGROUND AND PURPOSE: A variety of risk factors have been hypothesized to contribute to the development of fracture-healing complications; however, population-based estimates of the strength of these risk factors are limited. In this case-control study, we evaluated patient-related risk factors for fracture-healing complications. METHODS: Using the United Kingdom General Practice Research Database, we identified patients with a fracture-healing complication (delayed union, nonunion, or malunion) between 1988 and 2008. 4 controls (i.e. patients with normal healing) were matched to each case on general practice, fracture site, fracture date, and length of history in the database. We used conditional logistic regression to estimate odds ratios (ORs) of various risk factors, including demographics, comorbidities, and medication use. RESULTS: Diabetes and use of non-steroidal anti-inflammatory drugs (NSAIDs) within 12 months before the initial fracture were associated with a higher odds of a fracture-healing complication (type-I diabetes: adjusted OR = 2.3, 95% CI: 1.3-3.8; type-II diabetes: adjusted OR = 2.3, CI: 1.4-3.7; NSAIDs: adjusted OR = 2.6, CI: 2.1-3.2). Patients who had a motor vehicle accident recorded within 1 month before their initial fracture were also at increased odds of a fracture-healing complication (adjusted OR = 2.6, CI: 1.2-5.4). INTERPRETATION: Diabetes, NSAID use, and a recent motor vehicle accident were most consistently associated with an increased risk of a fracture-healing complication, regardless of fracture site or specific fracture-healing complication. This analysis suggests that certain patient-related characteristics influence the development of fracture-healing complications in general, even though specific healing complications may differ by their mechanism.

Initiation of anaemia management in patients with chronic kidney disease not on dialysis in the Veterans Health Administration.

BACKGROUND: Erythropoiesis-stimulating agents (ESAs) are frequently used to treat anaemia of chronic kidney disease (CKD) in the dialysis setting; however, few data are available regarding factors influencing initiation of ESAs and other therapies in non-dialysis patients. METHODS: A retrospective cohort study of Veterans Health Administration data from 2003 to 2005 for 89 585 patients identified as having CKD and anaemia based on two outpatient estimated glomerular filtration rates <60 ml/min/1.73 m(2) and at least one outpatient haemoglobin (Hb) <11 g/dL. Hb levels, patient demographics, clinical and provider characteristics and procedures predicted ESA treatment initiation over 1 year of follow-up. Multivariable logistic and pooled logistic survival models identified predictors of ESA initiation. RESULTS: Overall, 6381 subjects (7.1%) initiated ESAs within 1 year of the index Hb; initiation was more common (8.6%) for patients with Hb <10 g/dL. Iron therapy use varied by initial Hb levels (27.6% to 52.4%) as did transfusions (12.5% to 42.8%); each was more common at lower Hb levels. Hbs rose to above 11 g/dL for 25-50% of patients in the absence of any treatment or by transfusion/iron therapy. Factors predicting time to ESA initiation included: nephrologist [odds ratio (OR = 2.3)] or haematologist care (OR = 2.2) and iron therapy (OR = 1.6). Transfusions increased for patients with increasing follow-up time. CONCLUSION: Iron therapy is more common than ESA treatment in patients with CKD and Hbs <11 g/dL in the VA. Correction of anaemia in the absence of any ESA treatment was common at higher Hbs levels, but much less so when Hb levels fell below 10 g/dL.

Greater Epoetin alfa (EPO) doses and short-term mortality risk among hemodialysis patients with hemoglobin levels less than 11 g/dL.

PURPOSE: We examined the association between high doses of Epoetin alfa (EPO), which are used to raise and maintain hemoglobin (Hb) levels within target ranges for hemodialysis patients, and short-term mortality risk using multivariable regression and an instrumental variable (IV) analysis. METHODS: We identified 32 734 patients receiving hemodialysis in 786 facilities from a large US dialysis provider between July 2000 and March 2002 who received care for >4 consecutive months, and had an Hb < 11 g/dL in the third month. We assessed dose titrations following the Hb < 11 g/dL and characterized facilities based on the percentage of patients with dose titrations >25% (instrument). We assessed deaths during the subsequent 90 days and evaluated the EPO dose-mortality association using conventional linear and IV regression. RESULTS: The study population had a mean (SD) age of 60.4 (15.0) years; 48% were white, 42% were black and 51% were male. In unadjusted analyses, high EPO doses were associated with 90-day mortality risk (Risk Difference, RD = 3.0 per 100 persons, 95%CI:2.3-3.6); mortality risk was attenuated after adjustment for confounding (RD = 1.5 per 100 persons, 95%CI:0.8-2.2) and not associated with high EPO dose in the pooled IV analysis, though confidence intervals (CI) were wide (RD = -0.4 per 100 persons, 95%CI:-3.2-2.4). CONCLUSIONS: The difference in risk estimates between the adjusted linear regression and the IV regression suggests that the short-term mortality related to EPO dosing may be largely attributable to confounding-by-indication for higher doses. The IV method, which was employed to address the possibility of residual confounding, yielded near null though imprecise effect estimates.

A Database Cohort Study to Assess the Risk of Angioedema Among Patients with Heart Failure Initiating Angiotensin-Converting Enzyme Inhibitors in the USA.

INTRODUCTION: Real-world evidence on the risk of angioedema associated with angiotensin-converting enzyme inhibitors (ACEIs) in patients with heart failure (HF) is scarce. OBJECTIVE: This non-interventional study aimed to estimate the incidence of and risk factors for angioedema in patients with HF initiating an ACEI in real-world practice. METHODS: This was a retrospective cohort study using claims data from the PharMetrics Plus database, supplemented with consumer health data, from 1 January 2007 to 31 March 2015. Patients with HF initiating an ACEI were followed up for a maximum of 1 year, until the first occurrence of angioedema or until cohort exit. Angioedema incidence rates were estimated and stratified by potential risk factors such as race, age, sex, and time from initiation of ACEI therapy. For each risk factor, the unadjusted and adjusted hazard ratio (HR) was calculated; exploratory analyses were carried out to account for all potential confounders. RESULTS: We identified 21,639 patients with HF initiating an ACEI (mean age 58 years; 35.6% women; mean follow-up 205 days). The 1-year incidence of angioedema per 1000 patient-years was 3.3 [95% confidence interval (CI) 2.4-4.5]. The incidence was higher in Black [6.2 (95% CI 3.1-12.5)] than in non-black [2.9 (95% CI 2.1-4.1)] patients, higher in women [5.2 (95% CI 3.4-7.9)] than in men [2.3 (95% CI 1.5-3.6)], and greatest in the first 30 days of ACEI therapy. CONCLUSIONS: The risk of angioedema in patients with HF initiating an ACEI observed in this study is in line with published estimates for the general patient population treated with ACEIs.

Interpreting treatment effects from clinical trials in the context of real-world risk information: end-stage renal disease prevention in older adults.

IMPORTANCE: Older adults are often excluded from clinical trials. The benefit of preventive interventions tested in younger trial populations may be reduced when applied to older adults in the clinical setting if they are less likely to survive long enough to experience those outcomes targeted by the intervention. OBJECTIVE: To extrapolate a treatment effect similar to those reported in major randomized clinical trials of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers for prevention of end-stage renal disease (ESRD) to a real-world population of older patients with chronic kidney disease. DESIGN, SETTING, AND PARTICIPANTS: Simulation study in a retrospective cohort conducted in Department of Veterans Affairs medical centers. We included 371 470 patients 70 years or older with chronic kidney disease. EXPOSURE: Level of estimated glomerular filtration rate (eGFR) and proteinuria. MAIN OUTCOMES AND MEASURES: Among members of this cohort, we evaluated the expected effect of a 30% reduction in relative risk on the number needed to treat (NNT) to prevent 1 case of ESRD over a 3-year period. These limits were selected to mimic the treatment effect achieved in major trials of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers for prevention of ESRD. These trials have reported relative risk reductions of 23% to 56% during observation periods of 2.6 to 3.4 years, yielding NNTs to prevent 1 case of ESRD of 9 to 25. RESULTS: The NNT to prevent 1 case of ESRD among members of this cohort ranged from 16 in patients with the highest baseline risk (eGFR of 15-29 mL/min/1.73 m(2) with a dipstick proteinuria measurement of ≥ 2+) to 2500 for those with the lowest baseline risk (eGFR of 45-59 mL/min/1.73 m(2) with negative or trace proteinuria and eGFR of ≥ 60 mL/min/1.73 m2 with dipstick proteinuria measurement of 1+). Most patients belonged to groups with an NNT of more than 100, even when the exposure time was extended over 10 years and in all sensitivity analyses. CONCLUSIONS AND RELEVANCE: Differences in baseline risk and life expectancy between trial subjects and real-world populations of older adults with CKD may reduce the marginal benefit to individual patients of interventions to prevent ESRD.

Accuracy of ICD-9 codes to identify nonunion and malunion and developing algorithms to improve case-finding of nonunion and malunion.

OBJECTIVE: To evaluate the accuracy of using ICD-9 codes to identify nonunions (NU) and malunions (MU) among adults with a prior fracture code and to explore case-finding algorithms. STUDY DESIGN: Medical chart review of potential NU (N=300) and MU (N=288) cases. True NU cases had evidence of NU and no evidence of MU in the chart (and vice versa for MUs) or were confirmed by the study clinician. Positive predictive values (PPV) were calculated for ICD-9 codes. Case-finding algorithms were developed by a classification and regression tree analysis using additional automated data, and these algorithms were compared to true case status. SETTING: Group Health Cooperative. RESULTS: Compared to true cases as determined from chart review, the PPV of ICD-9 codes for NU and MU were 89% (95% CI, 85-92%) and 47% (95% CI, 41-53%), respectively. A higher proportion of true cases (NU: 95%; 95% CI, 90-98%; MU: 56%; 95% CI, 47-66%) were found among subjects with 1+ additional codes occurring in the 12months following the initial code. There was no case-finding algorithm for NU developed given the high PPV of ICD-9 codes. For MU, the best case-finding algorithm classified people as an MU case if they had a fracture in the forearm, hand, or skull and had no visit with an NU diagnosis code in the 12-month post MU diagnosis. PPV for this MU case-finding algorithm increased to 84%. CONCLUSIONS: Identifying NUs with its ICD-9 code is reasonable. Identifying MUs with automated data can be improved by using a case-finding algorithm that uses additional information. Further validation of the MU algorithms in different populations is needed, as well as exploration of its performance in a larger sample.

Serum sclerostin and risk of hip fracture in older Caucasian women.

CONTEXT: Sclerostin, a protein secreted by osteocytes, inhibits bone formation. Individuals with genetic mutations that decrease the availability of sclerostin have very high bone mass. OBJECTIVE: The aim of this study was to examine the hypothesis that elevated serum sclerostin levels are associated with increased risk of hip fracture in older women. DESIGN, SETTING, AND PARTICIPANTS: This was a case-cohort study of a prospective, community-based cohort of 9704 women aged 65 yr or older. Sclerostin levels were measured in serum collected in 1989-1990 in 228 women with incident hip fractures and 227 women in a randomly selected sample; average follow-up time was 9.8 yr. RESULTS: Serum sclerostin levels were correlated with total hip bone mineral density (BMD; r = 0.27, P < 0.001). The risk of hip fracture increased across quartiles of serum sclerostin (test for trend, P < 0.001) and was significantly elevated among those in the fourth quartile (hazard risk 3.4, 95% confidence interval 1.7-7.0) compared with women in the lowest quartile, after adjusting for age, body mass index, estrogen use, history of fracture since age 50 yr, and total hip BMD. When dividing the cohort into eight groups by sclerostin quartile and median hip BMD, women with lower total hip BMD in the highest sclerostin quartile had a 22.3-fold (95% confidence interval 5.8-86.3) increased risk of fracture compared with women with higher total hip BMD in the lowest sclerostin quartile. CONCLUSIONS: We conclude that higher serum sclerostin levels are associated with a greater risk of hip fractures in older women. In addition, the risk of hip fracture is amplified when high sclerostin levels are combined with lower BMD.