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Recently Completed and Deposited Reports Data

Venous Thromboembolism Prophylaxis in Orthopedic Surgery [Entered Retrospectively]


Public Report Complete
Statistics: 149 Studies, 8 Key Questions, 8 Extraction Forms,
Date Created: Nov 05, 2014 04:25PM
Description: Objectives: This is an evidence report prepared by the University of Connecticut/Hartford Hospital Evidence-based Practice Center (EPC) examining the comparative efficacy and safety of prophylaxis for venous thromboembolism in major orthopedic surgery (total hip replacement [THR], total knee replacement [TKR], and hip fracture surgery [HFS]) and other nonmajor orthopedic surgeries (knee arthroscopy, injuries distal to the hip requiring surgery, and elective spine surgery). Data Sources. Medline, the Cochrane Central Register of Controlled Trials, and Scopus from 1980 to May 2011 with no language restrictions; Review Methods: Controlled trials of any size and controlled observational studies with >750 subjects were included in our comparative effectiveness review if they were in patients undergoing one of six a priori defined orthopedic surgeries; provided data on prespecified intermediate, final health, or harms outcomes; defined deep vein thrombosis (DVT) and pulmonary embolism (PE) according to rigorous criteria (where applicable), and included prophylactic products (pharmacologic or mechanical) available in the United States. Using predefined criteria, data on study design, interventions, quality criteria, study population, baseline characteristics, and outcomes were extracted. All of the available data were qualitatively evaluated and where possible, statistically pooled. We used random effects derived relative risks (RR) for most analyses and Peto’s Odds Ratios (OR) in comparisons of rare events both with 95 percent confidence intervals (CIs). I2 was used to detect statistical heterogeneity and Egger’s weighted regression statistics were used to assess for publication bias. The strength of evidence (SOE) and applicability of evidence (AOE) for each outcome was rated as insufficient (I), low (L), moderate (M), or high (H); Results: In major orthopedic surgery (THR, TKR, and HFS, respectively), the incidence of DVT (39 percent, 53 percent, 47 percent), PE (6 percent, 1 percent, 3 percent), major bleeding (1 percent, 3 percent, 8 percent), and minor bleeding (5 percent, 5 percent, not reported) were reported in the placebo/control groups of clinical trials. The SOE and AOE were predominantly low for THR and TKR and was insufficient HFS. In major orthopedic surgery, pharmacologic prophylaxis reduced major venous thromboembolism (VTE) (OR 0.21 [0.05 to 0.95], SOE: L, AOE: L), DVT (RR 0.56 [0.47 to 0.68], SOE: M, AOE: L), and proximal DVT (pDVT) (RR 0.53 [0.39 to 0.74], SOE: H, AOE: L), but increased minor bleeding (RR 1.67 [1.18 to 2.38], SOE: H, AOE: M). Prolonged prophylaxis for >28 days was superior to prophylaxis for 7 to 10 at reducing symptomatic objectively confirmed VTE (RR 0.38 [0.19 to 0.77], SOE: M, AOE: L), PE (OR 0.13 [0.04 to 0.47], SOE: H, AOE: L), DVT (RR 0.37 [0.21 to 0.64], SOE: M, AOE: M), and pDVT (RR 0.29 [0.16 to 0.52], SOE: H, AOE: M) but increased minor bleeding (OR 2.44 [1.41 to 4.20], SOE: H, AOE: M). Using both pharmacologic and mechanical prophylaxis reduced DVT (RR 0.48 [0.32 to 0.72] SOE: M, AOE: M) versus pharmacologic prophylaxis alone. Low molecular weight heparins (LMWHs) reduced PE (OR 0.48 [0.24 to 0.95], SOE: M, AOE: L), DVT (RR 0.80 [0.65 to 0.99], SOE: M, AOE: L), pDVT (RR 0.60 [0.38 to 0.93], SOE: H, AOE: L), major bleeding (OR 0.57 [0.37 to 0.88], SOE: H, AOE: L), and heparin induced thrombocytopenia (OR 0.12 [0.03 to 0.43], SOE: M, AOE: L) versus unfractionated heparin. LMWHs reduced DVT (RR 0.66 [0.55 to 0.79], SOE: L, AOE: M) but increased major bleeding (RR 1.92 [1.27 to 2.91], SOE: H, AOE: M), minor bleeding (RR 1.23 [1.06 to 1.43], SOE: M, AOE: M), and surgical site bleeding (OR 2.63 [1.31 to 5.28], SOE: L, AOE: L) versus vitamin K antagonists. LMWHs increased DVT (RR 1.99 [1.57 to 2.51], SOE: M, AOE: L) and pDVT (OR 2.19 [1.52 to 3.16], SOE: L, AOE: L) but reduced major bleeding (OR 0.65 [0.48 to 0.89], SOE: M, AOE: L) versus factor Xa inhibitors. Antiplatelets increased DVT (1.63 [1.11 to 2.39], SOE: M, AOE: L) versus mechanical prophylaxis. Unfractionated heparin increased DVT (RR 2.31 [1.34 to 4.00], SOE: M, AOE: L) and pDVT (OR 4.74 [2.99 to 7.49], SOE: M, AOE: L) versus direct thrombin inhibitors. Intermittent compression stocking decreased DVT (RR 0.06 [0.01 to 0.41], SOE: L, AOE: L) versus graduated compression stockings. We did not have adequate information to evaluate the role of inferior vena cava filter (IVC) filters or to evaluate the impact of prophylaxis on nonmajor orthopedic surgeries; Conclusions: In major orthopedic surgery, while the risk of developing deep vein thrombosis is highest followed by pulmonary embolism and major bleeding, there are inadequate data to say whether or not deep vein thrombosis causes pulmonary embolism or is an independent predictor of pulmonary embolism. The balance of benefits to harms is favorable for providing prophylaxis to these patients and to extend the period of prophylaxis beyond the standard 7–10 days. The comparative balance of benefits to harms for LMWHs are superior to unfractionated heparin. Other interclass comparisons either could not be made due to lack of data, showed similarities between classes on outcomes, or had offsetting effects where benefits of one class on efficacy was tempered by an increased risk of bleeding. The balance of benefits to harms for combined pharmacologic plus mechanical prophylaxis versus either strategy alone could not be determined. We could not determine the impact of IVC filters on outcomes or the impact of prophylaxis on the nonmajor orthopedic surgeries evaluated.

Effectiveness of Early Diagnosis, Prevention, and Treatment of Clostridium difficile Infection [Entered Retrospectively]


Public Report Complete
Statistics: 112 Studies, 10 Key Questions, 10 Extraction Forms,
Date Created: Sep 17, 2014 03:10PM
Description: Objectives: To conduct a systematic review and synthesize evidence for differences in the accuracy of diagnostic tests, and the effects of interventions to prevent and treat Clostridium difficile infection (CDI) in adult patients. Data Sources: Searching for relevant literature was conducted in MEDLINE, the Cochrane Library, and Allied and Complementary Medicine (AMED). ClinicalTrials.gov and expert consultants provided leads to additional studies. We also manually searched reference lists from relevant literature. Review Methods: Standard Evidence-based Practice Center methods were employed. Screening of abstracts and full text articles to identify studies meeting inclusion/exclusion criteria was performed by two independent reviewers. High-quality direct comparison studies were used to examine differences in diagnostic tests. Randomized controlled trials (RCTs) were used to examine comparative effectiveness of antibiotic treatment for CDI. Quality of data extraction was checked by separate reviewers. Quality ratings and strength of evidence grading was performed on included studies. Evidence on diagnostic tests was quantitatively synthesized focusing on differences between test sensitivities and specificities. Evidence on antibiotic treatment was quantitatively examined using pooled analysis. Qualitative narrative analysis was used to synthesize evidence from all available study types for environmental prevention and nonstandard prevention and treatment, with the exception of probiotics as primary prevention, for which a forest plot is provided. Results: Overall, literature was sparse and strength of evidence was generally low due to small sample sizes or lack of adequate controls. For diagnostic testing, direct comparisons of commercially available enzyme immunoassays for C. difficile toxins A and B did not find major differences in sensitivity or specificity. Limited evidence suggests that tests for genes related to the production of C. difficile toxins may be more sensitive than immunoassays for toxins A and B while the comparisons of these test specificities were inconsistent. Moderate evidence in favor of antibiotic restriction policies for prevention was found. Environmental preventive interventions such as glove use and disposable thermometers have limited evidence. However, this literature is largely based on controlling outbreaks. Use of multiple component interventions further limits the ability to synthesize evidence in a meaningful way. Numerous potential new forms of treatment are being examined in placebo controlled RCTs, case series, and case reports. For standard treatment, no antimicrobial is clearly superior for the initial cure of CDI. Recurrence is less frequent with fidaxomicin than with vancomycin. Monoclonal antibodies for prevention and fecal flora reconstitution for multiple recurrences appear promising. Conclusions: Given the frequency and severity of CDI and the fact that future reimbursement policy may withhold payment for hospital-acquired infections, this is an under-researched topic. More precise estimates of the magnitude of differences in test sensitivities and specificities are needed. More importantly, studies have not established that any of the possible differences in test accuracy would lead to substantially different patient outcomes in clinical practice. More research on effective treatment and unintended consequences of treatment, such as resistance, is needed. Gut flora may be important, but improved understanding of healthy gut ecology and the complex interactions is necessary before continuing to pursue probiotics.

Treatment To Prevent Fractures in Men and Women With Low Bone Density or Osteoporosis: Update of a 2007 Report [Entered Retrospectively]


Public Report Complete
Statistics: 182 Studies, 5 Key Questions, 5 Extraction Forms,
Date Created: Aug 05, 2014 07:36PM
Description: Objectives: To update a 2007 systematic review on the effectiveness and safety of treatments to prevent fractures in persons with low bone density or osteoporosis and factors affecting adherence to these treatments, and to assess whether monitoring helps identify those most likely to benefit from treatment and the benefits of long-term treatment. Data Sources: MEDLINE®, Embase, the Cochrane Database of Systematic Reviews, and Clinical Trials.gov were searched from January 2005 through March 2011. Review Methods: After review by two investigators against predetermined inclusion/exclusion criteria, we included existing systematic reviews, randomized controlled clinical trials, and large observational studies, where appropriate, for assessment of treatment efficacy, safety, and adherence. Results: Alendronate, risedronate, zoledronic acid, denosumab, and teriparatide reduce the risk of vertebral and nonvertebral fractures among postmenopausal women with osteoporosis. Ibandronate and raloxifene reduce the risk of vertebral but not nonvertebral fractures. Alendronate, risedronate, zoledronic acid, and denosumab prevent hip fractures among postmenopausal women with osteoporosis. Risedronate decreases the risk of vertebral and nonvertebral fracture among men with osteoporosis. Among those treated with glucocorticoids, fracture risk reduction was demonstrated for risedronate and alendronate compared to placebo; and for teriparatide compared to alendronate. Few studies have compared osteoporosis therapies head-to-head. Adherence to pharmacotherapy is poor in patients with osteoporosis, as with other chronic conditions. Many factors affect adherence to medications, including dosing frequency, side effects of medications, knowledge about osteoporosis, and cost. Age, prior history of fracture, and concomitant medication use do not appear to have an independent association with adherence. Dosing frequency appears to affect adherence: Adherence is improved with weekly compared to daily regimens, but evidence is lacking to show that monthly regimens improve adherence over that of weekly regimens. Decreased adherence to bisphosphonates is associated with less than optimal reduction in the risk of fracture. Insufficient evidence is available to make conclusions about how adherence to and persistence with newer osteoporosis therapies compare to that with bisphosphonates. Assessment of adverse effects finds that raloxifene is associated with an increased risk for pulmonary embolism and vasomotor flushing; and limited data support a possible association between bisphosphonate use and atypical subtrochanteric fractures of the femur. Evidence is limited on the utility of monitoring and long-term treatment. Conclusions: There is a high level of evidence that shows that fracture risk reduction is greatest in women with a diagnosis of osteoporosis and/or prevalent fractures. The level of evidence is low to moderate for fracture risk reduction in postmenopausal women with osteopenia and without prevalent fractures. The evidence is low for benefits of treatment for other populations, including men; for the benefits and risks of long-term treatment; and for the need (if any) for monitoring bone density; and mixed with regard to factors that influence adherence.

Venous Thromboembolism Prophylaxis in Orthopedic Surgery [Entered Retrospectively]


Public Report Complete
Statistics: 149 Studies, 8 Key Questions, 8 Extraction Forms,
Date Created: Nov 05, 2014 04:25PM
Description: Objectives: This is an evidence report prepared by the University of Connecticut/Hartford Hospital Evidence-based Practice Center (EPC) examining the comparative efficacy and safety of prophylaxis for venous thromboembolism in major orthopedic surgery (total hip replacement [THR], total knee replacement [TKR], and hip fracture surgery [HFS]) and other nonmajor orthopedic surgeries (knee arthroscopy, injuries distal to the hip requiring surgery, and elective spine surgery). Data Sources. Medline, the Cochrane Central Register of Controlled Trials, and Scopus from 1980 to May 2011 with no language restrictions; Review Methods: Controlled trials of any size and controlled observational studies with >750 subjects were included in our comparative effectiveness review if they were in patients undergoing one of six a priori defined orthopedic surgeries; provided data on prespecified intermediate, final health, or harms outcomes; defined deep vein thrombosis (DVT) and pulmonary embolism (PE) according to rigorous criteria (where applicable), and included prophylactic products (pharmacologic or mechanical) available in the United States. Using predefined criteria, data on study design, interventions, quality criteria, study population, baseline characteristics, and outcomes were extracted. All of the available data were qualitatively evaluated and where possible, statistically pooled. We used random effects derived relative risks (RR) for most analyses and Peto’s Odds Ratios (OR) in comparisons of rare events both with 95 percent confidence intervals (CIs). I2 was used to detect statistical heterogeneity and Egger’s weighted regression statistics were used to assess for publication bias. The strength of evidence (SOE) and applicability of evidence (AOE) for each outcome was rated as insufficient (I), low (L), moderate (M), or high (H); Results: In major orthopedic surgery (THR, TKR, and HFS, respectively), the incidence of DVT (39 percent, 53 percent, 47 percent), PE (6 percent, 1 percent, 3 percent), major bleeding (1 percent, 3 percent, 8 percent), and minor bleeding (5 percent, 5 percent, not reported) were reported in the placebo/control groups of clinical trials. The SOE and AOE were predominantly low for THR and TKR and was insufficient HFS. In major orthopedic surgery, pharmacologic prophylaxis reduced major venous thromboembolism (VTE) (OR 0.21 [0.05 to 0.95], SOE: L, AOE: L), DVT (RR 0.56 [0.47 to 0.68], SOE: M, AOE: L), and proximal DVT (pDVT) (RR 0.53 [0.39 to 0.74], SOE: H, AOE: L), but increased minor bleeding (RR 1.67 [1.18 to 2.38], SOE: H, AOE: M). Prolonged prophylaxis for >28 days was superior to prophylaxis for 7 to 10 at reducing symptomatic objectively confirmed VTE (RR 0.38 [0.19 to 0.77], SOE: M, AOE: L), PE (OR 0.13 [0.04 to 0.47], SOE: H, AOE: L), DVT (RR 0.37 [0.21 to 0.64], SOE: M, AOE: M), and pDVT (RR 0.29 [0.16 to 0.52], SOE: H, AOE: M) but increased minor bleeding (OR 2.44 [1.41 to 4.20], SOE: H, AOE: M). Using both pharmacologic and mechanical prophylaxis reduced DVT (RR 0.48 [0.32 to 0.72] SOE: M, AOE: M) versus pharmacologic prophylaxis alone. Low molecular weight heparins (LMWHs) reduced PE (OR 0.48 [0.24 to 0.95], SOE: M, AOE: L), DVT (RR 0.80 [0.65 to 0.99], SOE: M, AOE: L), pDVT (RR 0.60 [0.38 to 0.93], SOE: H, AOE: L), major bleeding (OR 0.57 [0.37 to 0.88], SOE: H, AOE: L), and heparin induced thrombocytopenia (OR 0.12 [0.03 to 0.43], SOE: M, AOE: L) versus unfractionated heparin. LMWHs reduced DVT (RR 0.66 [0.55 to 0.79], SOE: L, AOE: M) but increased major bleeding (RR 1.92 [1.27 to 2.91], SOE: H, AOE: M), minor bleeding (RR 1.23 [1.06 to 1.43], SOE: M, AOE: M), and surgical site bleeding (OR 2.63 [1.31 to 5.28], SOE: L, AOE: L) versus vitamin K antagonists. LMWHs increased DVT (RR 1.99 [1.57 to 2.51], SOE: M, AOE: L) and pDVT (OR 2.19 [1.52 to 3.16], SOE: L, AOE: L) but reduced major bleeding (OR 0.65 [0.48 to 0.89], SOE: M, AOE: L) versus factor Xa inhibitors. Antiplatelets increased DVT (1.63 [1.11 to 2.39], SOE: M, AOE: L) versus mechanical prophylaxis. Unfractionated heparin increased DVT (RR 2.31 [1.34 to 4.00], SOE: M, AOE: L) and pDVT (OR 4.74 [2.99 to 7.49], SOE: M, AOE: L) versus direct thrombin inhibitors. Intermittent compression stocking decreased DVT (RR 0.06 [0.01 to 0.41], SOE: L, AOE: L) versus graduated compression stockings. We did not have adequate information to evaluate the role of inferior vena cava filter (IVC) filters or to evaluate the impact of prophylaxis on nonmajor orthopedic surgeries; Conclusions: In major orthopedic surgery, while the risk of developing deep vein thrombosis is highest followed by pulmonary embolism and major bleeding, there are inadequate data to say whether or not deep vein thrombosis causes pulmonary embolism or is an independent predictor of pulmonary embolism. The balance of benefits to harms is favorable for providing prophylaxis to these patients and to extend the period of prophylaxis beyond the standard 7–10 days. The comparative balance of benefits to harms for LMWHs are superior to unfractionated heparin. Other interclass comparisons either could not be made due to lack of data, showed similarities between classes on outcomes, or had offsetting effects where benefits of one class on efficacy was tempered by an increased risk of bleeding. The balance of benefits to harms for combined pharmacologic plus mechanical prophylaxis versus either strategy alone could not be determined. We could not determine the impact of IVC filters on outcomes or the impact of prophylaxis on the nonmajor orthopedic surgeries evaluated.

Effectiveness of Early Diagnosis, Prevention, and Treatment of Clostridium difficile Infection [Entered Retrospectively]


Public Report Complete
Statistics: 112 Studies, 10 Key Questions, 10 Extraction Forms,
Date Created: Sep 17, 2014 03:10PM
Description: Objectives: To conduct a systematic review and synthesize evidence for differences in the accuracy of diagnostic tests, and the effects of interventions to prevent and treat Clostridium difficile infection (CDI) in adult patients. Data Sources: Searching for relevant literature was conducted in MEDLINE, the Cochrane Library, and Allied and Complementary Medicine (AMED). ClinicalTrials.gov and expert consultants provided leads to additional studies. We also manually searched reference lists from relevant literature. Review Methods: Standard Evidence-based Practice Center methods were employed. Screening of abstracts and full text articles to identify studies meeting inclusion/exclusion criteria was performed by two independent reviewers. High-quality direct comparison studies were used to examine differences in diagnostic tests. Randomized controlled trials (RCTs) were used to examine comparative effectiveness of antibiotic treatment for CDI. Quality of data extraction was checked by separate reviewers. Quality ratings and strength of evidence grading was performed on included studies. Evidence on diagnostic tests was quantitatively synthesized focusing on differences between test sensitivities and specificities. Evidence on antibiotic treatment was quantitatively examined using pooled analysis. Qualitative narrative analysis was used to synthesize evidence from all available study types for environmental prevention and nonstandard prevention and treatment, with the exception of probiotics as primary prevention, for which a forest plot is provided. Results: Overall, literature was sparse and strength of evidence was generally low due to small sample sizes or lack of adequate controls. For diagnostic testing, direct comparisons of commercially available enzyme immunoassays for C. difficile toxins A and B did not find major differences in sensitivity or specificity. Limited evidence suggests that tests for genes related to the production of C. difficile toxins may be more sensitive than immunoassays for toxins A and B while the comparisons of these test specificities were inconsistent. Moderate evidence in favor of antibiotic restriction policies for prevention was found. Environmental preventive interventions such as glove use and disposable thermometers have limited evidence. However, this literature is largely based on controlling outbreaks. Use of multiple component interventions further limits the ability to synthesize evidence in a meaningful way. Numerous potential new forms of treatment are being examined in placebo controlled RCTs, case series, and case reports. For standard treatment, no antimicrobial is clearly superior for the initial cure of CDI. Recurrence is less frequent with fidaxomicin than with vancomycin. Monoclonal antibodies for prevention and fecal flora reconstitution for multiple recurrences appear promising. Conclusions: Given the frequency and severity of CDI and the fact that future reimbursement policy may withhold payment for hospital-acquired infections, this is an under-researched topic. More precise estimates of the magnitude of differences in test sensitivities and specificities are needed. More importantly, studies have not established that any of the possible differences in test accuracy would lead to substantially different patient outcomes in clinical practice. More research on effective treatment and unintended consequences of treatment, such as resistance, is needed. Gut flora may be important, but improved understanding of healthy gut ecology and the complex interactions is necessary before continuing to pursue probiotics.

Treatment To Prevent Fractures in Men and Women With Low Bone Density or Osteoporosis: Update of a 2007 Report [Entered Retrospectively]


Public Report Complete
Statistics: 182 Studies, 5 Key Questions, 5 Extraction Forms,
Date Created: Aug 05, 2014 07:36PM
Description: Objectives: To update a 2007 systematic review on the effectiveness and safety of treatments to prevent fractures in persons with low bone density or osteoporosis and factors affecting adherence to these treatments, and to assess whether monitoring helps identify those most likely to benefit from treatment and the benefits of long-term treatment. Data Sources: MEDLINE®, Embase, the Cochrane Database of Systematic Reviews, and Clinical Trials.gov were searched from January 2005 through March 2011. Review Methods: After review by two investigators against predetermined inclusion/exclusion criteria, we included existing systematic reviews, randomized controlled clinical trials, and large observational studies, where appropriate, for assessment of treatment efficacy, safety, and adherence. Results: Alendronate, risedronate, zoledronic acid, denosumab, and teriparatide reduce the risk of vertebral and nonvertebral fractures among postmenopausal women with osteoporosis. Ibandronate and raloxifene reduce the risk of vertebral but not nonvertebral fractures. Alendronate, risedronate, zoledronic acid, and denosumab prevent hip fractures among postmenopausal women with osteoporosis. Risedronate decreases the risk of vertebral and nonvertebral fracture among men with osteoporosis. Among those treated with glucocorticoids, fracture risk reduction was demonstrated for risedronate and alendronate compared to placebo; and for teriparatide compared to alendronate. Few studies have compared osteoporosis therapies head-to-head. Adherence to pharmacotherapy is poor in patients with osteoporosis, as with other chronic conditions. Many factors affect adherence to medications, including dosing frequency, side effects of medications, knowledge about osteoporosis, and cost. Age, prior history of fracture, and concomitant medication use do not appear to have an independent association with adherence. Dosing frequency appears to affect adherence: Adherence is improved with weekly compared to daily regimens, but evidence is lacking to show that monthly regimens improve adherence over that of weekly regimens. Decreased adherence to bisphosphonates is associated with less than optimal reduction in the risk of fracture. Insufficient evidence is available to make conclusions about how adherence to and persistence with newer osteoporosis therapies compare to that with bisphosphonates. Assessment of adverse effects finds that raloxifene is associated with an increased risk for pulmonary embolism and vasomotor flushing; and limited data support a possible association between bisphosphonate use and atypical subtrochanteric fractures of the femur. Evidence is limited on the utility of monitoring and long-term treatment. Conclusions: There is a high level of evidence that shows that fracture risk reduction is greatest in women with a diagnosis of osteoporosis and/or prevalent fractures. The level of evidence is low to moderate for fracture risk reduction in postmenopausal women with osteopenia and without prevalent fractures. The evidence is low for benefits of treatment for other populations, including men; for the benefits and risks of long-term treatment; and for the need (if any) for monitoring bone density; and mixed with regard to factors that influence adherence.



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The data contained in this project are distributed under the terms of the Creative Commons Attribution-NonCommerical license, which permits the use, dissemination, and reproduction in any medium, provided the original work is properly cited, and that the use is non-commercial and otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/3.0/

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