Effects of Zoledronate on Mortality and Morbidity after Surgical Treatment of Hip Fractures

Systemically administered zoledronic acid activates locally implanted synthetic hydroxyapatite particles enhancing peri-implant bone formation: A regenerative medicine approach to improve fracture fixation

Fracture fixation in an ageing population is challenging and fixation failure increases mortality and societal costs. We report a novel fracture fixation treatment by applying a hydroxyapatite (HA) based biomaterial at the bone-implant interface and biologically activating the biomaterial by systemic administration of a bisphosphonate (zoledronic acid, ZA). We first used an animal model of implant integration and applied a calcium sulphate (CaS)/HA biomaterial around a metallic screw in the tibia of osteoporotic rats. Using systemic ZA administration at 2-weeks post-surgery, we demonstrated that the implant surrounded by HA particles showed significantly higher peri‑implant bone formation compared to the unaugmented implants at 6-weeks. We then evaluated the optimal timing (day 1, 3, 7 and 14) of ZA administration to achieve a robust effect on peri‑implant bone formation. Using fluorescent ZA, we demonstrated that the uptake of ZA in the CaS/HA material was the highest at 3- and 7-days post-implantation and the uptake kinetics had a profound effect on the eventual peri‑implant bone formation. We furthered our concept in a feasibility study on trochanteric fracture patients randomized to either CaS/HA augmentation or no augmentation followed by systemic ZA treatment. Radiographically, the CaS/HA group showed signs of increased peri‑implant bone formation compared with the controls. Finally, apart from HA, we demonstrated that the concept of biologically activating a ceramic material by ZA could also be applied to β-tricalcium phosphate. This novel approach for fracture treatment that enhances immediate and long-term fracture fixation in osteoporotic bone could potentially reduce reoperations, morbidity and mortality. STATEMENT OF SIGNIFICANCE: • Fracture fixation in an ageing population is challenging. Biomaterial-based augmentation of fracture fixation devices has been attempted but lack of satisfactory biological response limits their widespread use. • We report the biological activation of locally implanted microparticulate hydroxyapatite (HA) particles placed around an implant by systemic administration of the bisphosphonate zoledronic acid (ZA). The biological activation of HA by ZA enhances peri‑implant bone formation. •Timing of ZA administration after HA implantation is critical for optimal ZA uptake and consequently determines the extent of peri‑implant bone formation. • We translate the developed concept from small animal models of implant integration to a proof-of-concept clinical study on osteoporotic trochanteric fracture patients. • ZA based biological activation can also be applied to other calcium phosphate biomaterials.

In vitro and in vivo effects of zoledronic acid on senescence and senescence-associated secretory phenotype markers

In addition to reducing fracture risk, zoledronic acid has been found in some studies to decrease mortality in humans and extend lifespan and healthspan in animals. Because senescent cells accumulate with aging and contribute to multiple co-morbidities, the non-skeletal actions of zoledronic acid could be due to senolytic (killing of senescent cells) or senomorphic (inhibition of the secretion of the senescence-associated secretory phenotype [SASP]) actions. To test this, we first performed in vitro senescence assays using human lung fibroblasts and DNA repair-deficient mouse embryonic fibroblasts, which demonstrated that zoledronic acid killed senescent cells with minimal effects on non-senescent cells. Next, in aged mice treated with zoledronic acid or vehicle for 8 weeks, zoledronic acid significantly reduced circulating SASP factors, including CCL7, IL-1β, TNFRSF1A, and TGFβ1 and improved grip strength. Analysis of publicly available RNAseq data from CD115+ (CSF1R/c-fms+) pre-osteoclastic cells isolated from mice treated with zoledronic acid demonstrated a significant downregulation of senescence/SASP genes (SenMayo). To establish that these cells are potential senolytic/senomorphic targets of zoledronic acid, we used single cell proteomic analysis (cytometry by time of flight [CyTOF]) and demonstrated that zoledronic acid significantly reduced the number of pre-osteoclastic (CD115+/CD3e-/Ly6G-/CD45R-) cells and decreased protein levels of p16, p21, and SASP markers in these cells without affecting other immune cell populations. Collectively, our findings demonstrate that zoledronic acid has senolytic effects in vitro and modulates senescence/SASP biomarkers in vivo. These data point to the need for additional studies testing zoledronic acid and/or other bisphosphonate derivatives for senotherapeutic efficacy.

Zoledronic Acid Does Not Retard Bone Union: A Randomized Controlled Trial in Fragility Intertrochanteric Femur Fractures

BACKGROUND

Fragility hip fracture is a leading cause of death in the elderly and is common in postmenopausal women and elderly people. In the treatment of osteoporosis, bisphosphonates (BPs) are often considered first-line medications. Zoledronic acid is the most potent and long-acting BP in clinical use and is administered as an intravenous infusion. In the context of acute fractures, the use of BPs has been controversial due to conflicting reports of their positive and negative effects on fracture healing. The purpose of this study was to determine the effect of zoledronic acid on fracture healing in intertrochanteric (IT) fragility fractures.

METHODS

The study was conducted in a tertiary healthcare center after receiving scientific and ethical approval. The study included 136 patients of either gender over the age of 50 who presented with an IT femur fracture after minor trauma between November 2020 and November 2022. The total number of patients had been classified into two groups, and grouping involved random sampling: Group T (test group, n = 68; zoledronic acid injections were given on postoperative day 3) and Group C (control group, n = 68; interventions were given after fracture healing). Patients were evaluated using the Radiographic Union Score for Hip (RUSH) and Singh Index for radiological outcomes and the Harris Hip Score (HHS) for functional outcomes. The patients were followed for six months.

RESULTS

The overall mean age was 73.25 years; in Group T, it was 72.5 ± 11.9 years, and in Group C, it was 73.7 ± 11.8 years. Of 136 patients, 69 (51%) were males and 67 (49%) were females. The average fracture healing time in Group T was 12.2 ± 3.6 weeks, while it was 13.0 ± 2.8 weeks in Group C. Functional outcomes, including HHS, were found to be better in Group T than in Group C (p < 0.005). No significant difference was observed between the two groups with respect to the radiological union, the RUSH score, or Singh Index, implying no negative effect of zoledronic acid.

CONCLUSIONS

This study demonstrates that postoperative intravenous zoledronic acid therapy does not retard fracture healing. Osteoporosis management is frequently neglected because of a surgeon's fear of ZOL retarding fracture healing and a lack of awareness among patients, resulting in low compliance. Thus, opportunistic administration of zoledronic acid postoperatively can be beneficial and will increase compliance for osteoporosis management and fracture prevention to 100%.

Denosumab versus zoledronic acid in elderly patients after hip fracture

BACKGROUND

Two injectable anti-osteoporosis medications, denosumab and zoledronic acid, have been widely used to treat patients with severe osteoporosis. The purpose of this study was to evaluate the real-world effectiveness and adherence of denosumab compared to zoledronic acid in geriatric patients after a hip fracture.

METHODS

A total of 282 patients treated with osteoporotic hip fracture between March 2014 and Aug 2022 were retrospectively reviewed. The patients were asked to select the anti-osteoporosis medication after surgery. Treatment persistence was monitored by follow-up visit to the outpatient clinic at postoperative 2 years.

RESULTS

Of 282 individuals with baseline data, 162 patients took subcutaneous denosumab and 120 patients took intravenous zoledronic acid. At postoperative 2 years, the change in bone mineral density (BMD) from baseline was greater in the denosumab group compared with the zoledronic acid group (p < 0.001). The rate of persistence to denosumab was significantly higher than that for 12-months zoledronic acid (p = 0.01). Serious adverse events were similar in the two groups.

CONCLUSIONS

Our study revealed the effectiveness and patients' persistence for two commonly used anti-osteoporosis agents after hip fracture. In this frail, elderly population, half-yearly denosumab was superior to yearly zoledronic acid in BMD and demonstrated significant higher persistence rate, indicating a potential therapeutic advantage that warrants further validation.

Early bisphosphonate therapy post proximal femoral fracture fixation does not impact fracture healing: a systematic review and meta-analysis

BACKGROUND

There is conjecture on the optimal timing to administer bisphosphonate therapy following operative fixation of low-trauma hip fractures. Factors include recommendations for early opportunistic commencement of osteoporosis treatment, and clinician concern regarding the effect of bisphosphonates on fracture healing. We performed a systematic review and meta-analysis to determine if early administration of bisphosphonate therapy within the first month post-operatively following proximal femur fracture fixation is associated with delay in fracture healing or rates of delayed or non-union.

METHODS

We included randomized controlled trials examining fracture healing and union rates in adults with proximal femoral fractures undergoing osteosynthesis fixation methods and administered bisphosphonates within 1 month of operation with a control group. Data were pooled in meta-analyses where possible. The Cochrane Risk of Bias Tool and the GRADE approach were used to assess validity.

RESULTS

For the outcome of time to fracture union, meta-analysis of three studies (n = 233) found evidence for earlier average time to union for patients receiving early bisphosphonate intervention (MD = -1.06 weeks, 95% CI -2.01--0.12, I²  = 8%). There was no evidence from two included studies comprising 718 patients of any difference in rates of delayed union (RR 0.61, 95% CI 0.25-1.46). Meta-analyses did not demonstrate a difference in outcomes of mortality, function or pain.

CONCLUSIONS

We provide low-level evidence that there is no reduction in time to healing or delay in bony union for patients receiving bisphosphonates within 1 month of proximal femur fixation.

Effects of the Revised Reimbursement Guideline for Anti-Osteoporosis Medication in South Korea

BACKGROUND

The Korean National Health Insurance (NHI) reimbursement guideline was revised in May 2015 with the aim of preventing secondary osteoporotic fractures. Here we compared the: (1) rate of bone mineral density (BMD) measurements; (2) prescription rate of anti-osteoporosis medication within 3 months after hip fracture surgery (HFS); (3) incidence of a second hip fracture; and (4) first-year mortality rate after HFS.

METHODS

This before-after study used the revised reimbursement system as a reference period. We retrospectively reviewed the medical records of 515 patients who underwent HFS at a tertiary referral hospital between January 2014 and December 2016. The period 1 group underwent HFS in 2014, while the period 2 group underwent HFS in 2016.

RESULTS

Despite the fact that there was no significant intergroup difference in BMD measurement rate, the period 2 group had a higher prescription rate for anti-osteoporosis drugs within 3 months of HFS. However, the incidence of a second hip fracture did not differ between groups. The first-year mortality rate was higher in the period 1 versus period 2 group.

CONCLUSIONS

Revision of the NHI guideline in May 2015 was associated with an increased prescription rate of anti-osteoporosis medication in osteoporotic hip fracture patients.

Timing of osteoporosis therapies following fracture: the current status

In most patients, osteoporosis is diagnosed only after the occurrence of the first fragility fracture. It is of utmost importance to start osteoporosis medications immediately in these patients to prevent future fractures and also to reduce associated mortality and morbidity. There remains a hesitancy over initiating osteoporotic medications, specifically for antiresorptive agents like bisphosphonates following an acute fracture due to concern over their effect on fracture healing. The purpose of this review is to study the effect of the timing of initiation of different osteoporosis medications on healing after an acute fracture. Most of the human studies, including randomized control trials (RCTs), did not find any significant negative effect on fracture healing with early use of bisphosphonate after an acute fracture. Anabolic agents like teriparatide have shown either neutral or beneficial effects on fracture healing and thus can be started very early following any osteoporotic fracture. Although human studies on the early use of other osteoporosis medications like denosumab or strontium ranelate are very sparse in the literature, none of these medications have shown any evidence of delay in fracture healing. To summarize, among the commonly used anti-osteoporosis agents, both bisphosphonates and teriparatide are safe to be initiated in the early acute post-fracture period. Moreover, teriparatide has shown some evidence in favor of reducing fracture healing time.

Intravenous bisphosphonate therapy does not delay fracture healing in inter-trochanteric femur fractures - A randomised controlled study

Hip fractures in elderly are commonly associated with osteoporosis and surgical outcome is influenced by its concurrent management. The purpose of our study is to determine the association between timing of bisphosphonate administration in inter-trochanteric (IT) fractures and fracture healing. Patients with IT fractures (aged≥50 years) and T-score ≤ -1.5 [WHO defines osteopenia as T-score between -1 and -2.5, and osteoporosis as T-score ≤ -2.5 on DEXA scan (which was obtained post-operatively in our cohort)], who underwent proximal femoral nailing were included. Patients were divided into three groups: group 1a-intravenous bisphosphonate {ivBP [zoledronic acid (ZA)]} given within one week, group 1b-ZA at six weeks and group 2-control group. Post-operative radiographs were assessed for reduction parameters [neck-shaft angle, tip-apex distance, reduction variance]. Radiological union was determined using RUSH score and functional outcome (at one year) with Modified Harris Hip Scores. 41 (23 males), 40 (15 males) and 42 (15 males) patients were included in groups 1a, 1b and 2, respectively (no statistical difference in sex distribution among the groups; p = 0.12). Mean age in groups 1a, 1b and 2 was 71.8 ± 8.1, 75.9 ± 8.5 and 72.3 ± 10.6 years (p = 0.09). There was no significant difference in the pattern of injuries (AO classification) among the groups (p = 0.72). Mean time to union in groups 1a, 1b and 2 was 13.7,13.7 and 14.2 weeks, respectively (p = 0.69). Mean time to union in AO types A1, A2 and A3 fractures was 13.2 ± 2.1, 13.7 ± 2.8 and 16.1 ± 4.9 weeks (p = 0.01). We did not observe any association between T-scores and fracture union (hip:p = 0.52, spine:p = 0.93).The functional outcome was similar among groups (p = 0.96). Early administration of ZA did not negatively influence fracture healing in patients undergoing fixation of IT fractures. Among the various other factors analyzed, there was a statistically significant association between the fracture type (AO type A3) and longer time to fracture union.

Fracture prevention: a population-based intervention delivered in primary care

BACKGROUND

Osteoporosis is common, increasing as the population ages and has significant consequences including fracture. Effective treatments are available.

AIM

To support proactive fracture risk assessment (FRAX) and optimizing treatment for high-risk patients in primary care.

DESIGN

Clinical cohort.

SETTING

November 2017 to November 2018, support was provided to 71 practices comprising 69 of 90 practices within two National Health Service Clinical Commissioning Groups areas. Total population 579 508 (207 263 aged over 50 years).

PARTICIPANTS

FRAX (National Institute for Care and Clinical Excellence, NICE CG146) in (i) males aged 75 years and over, (ii) females aged 65 years and over, (iii) females aged under 65 years and males aged under 75 years with risk factors and (iv) under 50 years with major risk factors.

RESULTS

A total of 158 946 met NICE CG146, 11 961 were coded with an osteoporosis diagnosis (7.5%), of those, 42% were prescribed treatment with a bone sparing agent (BSA). In total, 6942 were assessed to initiate BSA. Thirty percent of untreated osteoporosis diagnosis patients had never been prescribed BSA. Even when prescribed, 1700 people (35%) were for less than minimum recommended duration. Of the total 9784 patients within the FRAX recommended to treat threshold, 3197 (33%) were currently treated with BSA and 3684 (37%) had no history of ever receiving BSA. From untreated patients, expected incidence of 875 fractures over a 3-year period (approximately £3.4 million). Treatment would prevent 274 fractures (cost reduction: £1 274 045, with prescribing costs: saving £805 145 after 3 years of treatment).

CONCLUSION

Underdiagnosis and suboptimal treatment of osteoporosis was identified. Results suggest that implementing NICE guidance and optimizing treatment options in practice is possible and could prevent significant fractures.

Adherence to anti-osteoporosis medication associated with lower mortality following hip fracture in older adults: a nationwide propensity score-matched cohort study

Background

We investigated the association of anti-osteoporosis medication with mortality risk in older adults with hip fractures and evaluated the influence of medication adherence on mortality.

Methods

We conducted a population-based cohort study and identified a total of 13,123 patients aged 65 years or older with hip fracture from the Taiwan National Health Insurance Database during the period 2001–2010. Individuals with (n = 2092) and without (n = 2092) receiving anti-osteoporosis medication were matched using propensity score matching (1:1 ratio). The 1-, 3- and 5-year survival rates after the index fracture were compared between patients with and without treatment. In the treated group, survival rate was compared between those with good and non-adherence. Good adherence was defined as the medication possession ratio of ≥80% and non-adherence as a ratio < 80%.

Results

The 1-, 3- and 5-year mortality rates were significantly lower in the treated vs. the non-treated group (all p < 0.0001). In the treated group, the estimated 1-, 3- and 5-year survival rates were higher in those with good adherence than in those with non-adherence (all p < 0.0001). Regarding all-cause mortality, the adjusted hazard ratio in the treated vs. the non-treated group was 0.63 (95% confidence interval 0.58–0.68, p < 0.0001). The good adherence subgroup showed a significantly lower mortality risk than that in the non-adherence subgroup (hazard ratio 0.41, 95% confidence interval 0.32–0.51, p < 0.0001).

Conclusions

The 1-, 3- and 5-year survival rates were significantly higher in patients receiving anti-osteoporosis medication than in the untreated group. All-cause mortality rates were lower in patients with good adherence to anti-osteoporosis medication.

Anti-Osteoporosis Medications Associated with Decreased Mortality after Hip Fracture

Objective

To study the effect of anti‐osteoporosis therapies on mortality after hip fracture.

Methods

This retrospective study was carried out in the Second Affiliated Hospital of Fujian Medical University and enrolled 690 patients 50 years of age and older who were admitted with hip fractures between 2010 and 2015. The patients were followed in 2017: 690 patients aged was from 50 to 103 years. There were 456 women and 234 men. There were 335 patients with fractures of the femoral neck and 355 patients with intertrochanteric fractures of the femur. There were 444 (64.35%) patients who also had internal diseases. The Charlson comorbidity index was 0–6. The anti‐osteoporosis medications were classified into no anti‐osteoporosis medication, calcium + vitamin D supplementations, non‐bisphosphonate medication, and bisphosphonate medication. The physicians followed the patients or family members by personal visit and telephone. Multivariable Cox regression analyses were done with known risk factors for mortality of hip fracture, such as gender, age, number of combined internal diseases, fracture type, place of residence, and Charlson comorbidity index, to show which anti‐osteoporosis medications had significant effects on mortality after adjustment for these variables.

Results

Out of 690 patients with hip fractures, 149 patients received no anti‐osteoporosis medication, 63 patients received calcium +vitamin D supplementations, 398 patients received non‐bisphosphonate medication, and 80 patients received bisphosphonate medication. The patients were followed between 7 months and 52 months, with the average of 28.53 ± 9.75 months. A total of 166 patients died during the follow‐up period. Of 166 deaths, 43 occurred within 3 months, 65 within 6 months, and 99 within 1 year after the hip fracture. In this study, fracture type, place of residence, and Charlson comorbidity index were not associated with the mortality, and the male gender, age > 75 years, and ≥ 2 combined internal diseases were the independent factors for deaths post‐hip fracture. The cumulative mortality was 36.24% in the patients receiving no anti‐osteoporosis medication. The hazard ratio for mortality after hip fracture with bisphosphonate medication, non‐bisphosphonate medication, and calcium/vitamin D supplementation was 0.355 (95% CI, 0.194–0.648), 0.492 (95% CI, 0.347–0.699) and 0.616 (95% CI, 0.341–1.114), respectively, as compared with no anti‐osteoporosis group. Bisphosphonate and non‐bisphosphonate medications for osteoporosis were significantly associated with the reduction of cumulative mortality post‐hip fracture (P < 0.01).

Conclusions

Bisphosphonate and non‐bisphosphonate medications for osteoporosis were significantly associated with decreased mortality after fragility hip fracture.

Effects of Zoledronic Acid Treatment on Fracture Healing, Morbidity and Mortality in Elderly Patients with Osteoporotic Hip Fractures

Background

In this study, the effects of zoledronic acid (ZolA) administered at different times to patients undergoing surgical treatment for hip fracture were investigated.

Materials and methods

Ninety patients who underwent surgical treatment for osteoporotic (OP) hip fractures between February 2013 and September 2016 in our hospital were included in the study. After surgical treatment, patients were allocated into three groups: group I—patients who had osteosynthesis using proximal femoral nail (PFN) for an intertrochanteric fracture of the femur were given ZolA within 1 week after fracture and before discharge; group II—patients who had osteosynthesis using the PFN for an intertrochanteric fracture of the femur were given ZolA within 1 month after fracture post-discharge; group III—patients in the same age group who had a hemiarthroplasty (HA) for an intertrochanteric fracture of the femur were administered ZolA before discharge. In addition, all patients were given daily oral calcium and vitamin D3. The Radiographic Union Score for Hip (RUSH), Harris Hip Score (HHS), and bone mineral density (BMD) were used at the follow-up as evaluation criteria, and complications were noted.

Results

There were no significant differences between groups in terms of demographic data and laboratory outcomes (p > 0.05). Radiographic Union Score for Hip scores were similar between groups I and II (p > 0.05). Fracture union occurred by the sixth month in all patients whose results were evaluated. No statistically significant difference was found between three groups (p > 0.05). There was no difference between the three groups in the hip and vertebrae BMD and t scores (p > 0.05). When t and BMD scores before treatment were compared with those at 1 year after treatment, a benefit from ZolA treatment was observed in all three groups (p < 0.05).

Conclusion

This study shows that the timing of ZolA administration has no effect on fracture healing and complication incidence in elderly patients with hip fractures. In addition, ZolA was found to be beneficial in increasing BMD of both femur and vertebra in all groups, but there was no significant difference between the groups.

Clinical significance

The study demonstrated that ZolA may be used early in the treatment of osteoporotic hip fractures with PFN.

How to cite this article

Sargin S, Konya MN, Gulcu A, et al. Effects of Zoledronic Acid Treatment on Fracture Healing, Morbidity and Mortality in Elderly Patients with Osteoporotic Hip Fractures. Strategies Trauma Limb Reconstr 2019;14(3):126–131.

Efficacy, cost, and aspects to take into account in the treatment of osteoporosis in the elderly

Age is one of the principal risk factors for development of frailty fractures. Age pyramids show a population that is becoming increasingly more elderly, with an increasing incidence of fractures, and the forecasts for the future are truly alarming. Adequate handling of these patients who are especially at risk, at both the preventive and care levels, with a well-defined orthogeriatric model is necessary to respond to this clinical challenge. The objective of this review is to analyze the efficacy of the different strategies for the handling of geriatric patients with fracture risk.