A comparison of observational studies and randomized, controlled trials

Combined Aerobic and Resistance Training for Cardiorespiratory Fitness, Muscle Strength, and Walking Capacity after Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Cardiorespiratory fitness, measured as peak oxygen consumption, is a potent predictor of stroke risk. Muscle weakness is the most prominent impairment after stroke and is directly associated with reduced walking capacity. There is a lack of recommendations for optimal combined aerobic training and resistance training for those patients. The purpose of this study was to systematically review and quantify the effects of exercise training on cardiorespiratory fitness, muscle strength, and walking capacity after stroke.

METHODS

Five electronic databases were searched (until May 2019) for studies that met the following criteria: (1) adult humans with a history of stroke who ambulate independently; (2) structured exercise intervention based on combined aerobic training and resistance training; and (3) measured cardiorespiratory fitness, muscle strength, and/or walking capacity.

RESULTS

Eighteen studies (602 participants, average age 62 years) met the inclusion criteria. Exercise training significantly improved all 3 outcomes. In subgroup analyses for cardiorespiratory fitness, longer training duration was significantly associated with larger effect size. Likewise, for muscle strength, moderate weekly frequency and lower training volume were significantly associated with larger effect size. Furthermore, in walking capacity, moderate weekly frequency and longer training duration were significantly associated with larger effect size.

CONCLUSIONS

These results suggest that an exercise program consisting of moderate-intensity, 3 days per week, for 20 weeks should be considered for greater effect on cardiorespiratory fitness, muscle strength, and walking capacity in stroke patients.

Association of Receiving Multiple, Concurrent Fracture-Associated Drugs With Hip Fracture Risk

IMPORTANCE

Many prescription drugs increase fracture risk, which raises concern for patients receiving 2 or more such drugs concurrently. Logic suggests that risk will increase with each additional drug, but the risk of taking multiple fracture-associated drugs (FADs) is unknown.

OBJECTIVE

To estimate hip fracture risk associated with concurrent exposure to multiple FADs.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used a 20% random sample of Medicare fee-for-service administrative data for age-eligible Medicare beneficiaries from 2004 to 2014. Sex-stratified Cox regression models estimated hip fracture risk associated with current receipt of 1, 2, or 3 or more of 21 FADs and, separately, risk associated with each FAD and 2-way FAD combination vs no FADs. Models included sociodemographic characteristics, comorbidities, and use of non-FAD medications. Analyses began in November 2018 and were completed April 2019.

EXPOSURE

Receipt of prescription FADs.

MAIN OUTCOMES AND MEASURES

Hip fracture hospitalization.

RESULTS

A total of 11.3 million person-years were observed, reflecting 2 646 255 individuals (mean [SD] age, 77.2 [7.3] years, 1 615 613 [61.1%] women, 2 136 585 [80.7%] white, and 219 579 [8.3%] black). Overall, 2 827 284 person-years (25.1%) involved receipt of 1 FAD; 1 322 296 (11.7%), 2 FADs; and 954 506 (8.5%), 3 or more FADs. In fully adjusted, sex-stratified models, an increase in hip fracture risk among women was associated with the receipt of 1, 2, or 3 or more FADs (1 FAD: hazard ratio [HR], 2.04; 95% CI, 1.99-2.11; P < .001; 2 FADs: HR, 2.86; 95% CI, 2.77-2.95; P < .001; ≥3 FADs: HR, 4.50; 95% CI, 4.36-4.65; P < .001). Relative risks for men were slightly higher (1 FAD: HR, 2.23; 95% CI, 2.11-2.36; P < .001; 2 FADs: HR, 3.40; 95% CI, 3.20-3.61; P < .001; ≥3 FADs: HR, 5.18; 95% CI, 4.87-5.52; P < .001). Among women, 2 individual FADs were associated with HRs greater than 3.00; 80 pairs of FADs exceeded this threshold. Common, risky pairs among women included sedative hypnotics plus opioids (HR, 4.90; 95% CI, 3.98-6.02; P < .001), serotonin reuptake inhibitors plus benzodiazepines (HR, 4.50; 95% CI, 3.76-5.38; P < .001), and proton pump inhibitors plus opioids (HR, 4.00; 95% CI, 3.56-4.49; P < .001). Receipt of 1, 2, or 3 or more non-FADs was associated with a small, significant reduction in fracture risk compared with receipt of no non-FADs among women (1 non-FAD: HR, 0.93; 95% CI, 0.90-0.96; P < .001; 2 non-FADs: HR, 0.84; 95% CI, 0.81-0.87; P < .001; ≥3 non-FADs: HR, 0.74; 95% CI, 0.72-0.77; P < .001).

CONCLUSIONS AND RELEVANCE

Among older adults, FADs are commonly used and commonly combined. In this cohort study, the addition of a second and third FAD was associated with a steep increase in fracture risk. Many risky pairs of FADs included potentially avoidable drugs (eg, sedatives and opioids). If confirmed, these findings suggest that fracture risk could be reduced through tighter adherence to long-established prescribing guidelines and recommendations.

Study methodology in trauma care: towards question-based study designs

The randomized controlled trial (RCT) in surgery may not always be ethical, feasible, or necessary to address a particular research question about the effect of a surgical intervention. If so, properly designed and conducted observational (non-randomized) studies may be valuable alternatives for an RCT and produce credible results. In this paper, we discus differences between RCTs and observational studies and differentiate between three types of comparisons of surgical interventions. We assert that results of different designs should be regarded as complementary to each other when evaluating surgical interventions. Criteria for credible observational research are presented to provide guidance for future observational research of surgical interventions. We argue that the research question that is being asked should guide the discussion about the value of a particular study design.

Partially randomised patient preference trials as an alternative design to randomised controlled trials: systematic review and meta-analyses

OBJECTIVE

Randomised controlled trials (RCT) are the gold standard to provide unbiased data. However, when patients have a treatment preference, randomisation may influence participation and outcomes (eg, external and internal validity). The aim of this study was to assess the influence of patients' preference in RCTs by analysing partially randomised patient preference trials (RPPT); an RCT and preference cohort combined.

DESIGN

Systematic review and meta-analyses.

DATA SOURCES

MEDLINE, Embase, PsycINFO and the Cochrane Library.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

RPPTs published between January 2005 and October 2018 reporting on allocation of patients to randomised and preference cohorts were included.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data. The main outcomes were the difference in external validity (participation and baseline characteristics) and internal validity (lost to follow-up, crossover and the primary outcome) between the randomised and the preference cohort within each RPPT, compared in a meta-regression using a Wald test. Risk of bias was not assessed, as no quality assessment for RPPTs has yet been developed.

RESULTS

In total, 117 of 3734 identified articles met screening criteria and 44 were eligible (24 873 patients). The participation rate in RPPTs was >95% in 14 trials (range: 48%-100%) and the randomisation refusal rate was >50% in 26 trials (range: 19%-99%). Higher education, female, older age, race and prior experience with one treatment arm were characteristics of patients declining randomisation. The lost to follow-up and cross-over rate were significantly higher in the randomised cohort compared with the preference cohort. Following the meta-analysis, the reported primary outcomes were comparable between both cohorts of the RPPTs, mean difference 0.093 (95% CI -0.178 to 0.364, p=0.502).

CONCLUSIONS

Patients' preference led to a substantial proportion of a specific patient group refusing randomisation, while it did not influence the primary outcome within an RPPT. Therefore, RPPTs could increase external validity without compromising the internal validity compared with RCTs.

PROSPERO REGISTRATION NUMBER

CRD42019094438.

Treatment With Bupropion and Varenicline for Smoking Cessation and the Risk of Acute Cardiovascular Events and Injuries: a Swedish Case-Crossover Study

Introduction

Bupropion and varenicline are non-nicotine medications used for smoking cessation that mitigate craving and withdrawal symptoms. We aim to investigate whether these drugs increase the risk of selected acute adverse outcomes when used in medical practice.

Methods

Population-based case-crossover design using data from Swedish health and administrative registers. Adult individuals diagnosed with acute myocardial infarction, stroke, suicide, suicide attempt, fall injury, or that suffered a road traffic crash from 01.10.2006 for bupropion, or from 01.03.2008 for varenicline, until 31.12.2013 were included. Different lengths of exposure periods were analyzed within the 12-week hazard period prior to the adverse outcome (1-14, 15-28, and 29-84 days). The control period was matched using the interval preceding the hazard period (85-168 days), and breaking it up into equivalent periods (85-98, 99-112, and 113-168 days). Conditional logistic regression with each case considered as one stratum was used to estimate adjusted odds ratios (OR) and confidence intervals (CI).

Results

Neither medication was associated with consistent higher risks for any of the adverse outcomes. For bupropion and varenicline, respectively, in the 1-14 days hazard period, OR (95% CI) were: myocardial infarction 1.14 (0.55 to 2.34) and 1.06 (0.70 to 1.62); stroke 1.16 (0.39 to 3.47) and 1.26 (0.72 to 2.17), and traffic crashes 0.85 (0.39 to 1.85) and 1.48 (0.90 to 2.41). In the other periods, ORs were similar or even lower. For falls and suicidal events ORs were generally below one for both drugs.

Conclusion

The available evidence suggests that if prescription guidelines are properly followed regarding potential contraindications both of these medications could be considered relatively safe.

Implications

The reliable exposure and diagnosis assessment used in this nationwide register-based study, along with the number of cases gathered makes this sample one of the largest of its type to assess potential side effects associated with the use of these drugs. Neither medication was associated with consistent higher risks for any of the adverse outcomes studied.

Randomized controlled trials reflected clinical practice when comparing the course of low back pain symptoms in similar populations

OBJECTIVE

This study compares participants in randomized controlled trials (RCTs) (the Minimal Invasive Treatment [MinT] trials) to participants in a related observational study with regard to their low back pain (LBP) symptom course.

STUDY DESIGN AND SETTING

Eligible patients were diagnosed with chronic LBP originating from the facet joints (N = 615) or sacroiliac (SI) joints (N = 533) and were treated with radiofrequency denervation and an exercise program. Randomized patients were compared to patients in the related observational study who fulfilled all RCT eligibility criteria (observational group 1) and to patients who did not fulfill at least one of the RCT eligibility criteria (observational group 2). Outcomes were pain intensity, treatment success, and functional status over a 3-month period. Longitudinal mixed-model analyses and linear regression models were applied to analyze the differences in outcomes between the RCT and observational study groups.

RESULTS

No differences in symptom course were found between patients in the RCTs and patients in observational group 1. Patients with facet joint pain in observational group 2 had overall less treatment success (odds ratios [OR], 0.67; 95% confidence interval [CI], 0.50-0.90), and less improvement in physical functioning (mean difference [MD], 5.82; 95% CI, 2.54-9.11) compared to the RCT patients. Patients with SI joint pain in observational group 2 had higher pain scores (MD, 0.40; 95% CI, 0.09-0.72), less treatment success (OR, 0.72; 95% CI, 0.54-0.96), and less improvement in physical functioning (MD, 7.16; 95% CI, 3.84-10.47) compared to the RCT patients.

CONCLUSION

This supports the generalizability of results from the MinT RCTs as this study suggests that these RCTs reflect clinical practice when comparing similar populations. To what extent this holds true for all RCTs in LBP should be further explored.

Comparing the Effect of Folic Acid and Pentoxifylline on Delaying Dialysis Initiation in Patients with Advanced Chronic Kidney Disease

Background: We hypothesized that the nutrient loss and chronic inflammation status may stimulate progression in advanced chronic kidney disease. Therefore, we aimed to generate a study to state the influence of combined nutritional and anti-inflammatory interventions. Methods: The registry from the National Health Insurance Research Database in Taiwan was searched for 20–90 years individuals who had certified end-stage renal disease. From January 2005 through December 2010, the diagnosis code ICD-9 585 (chronic kidney disease, CKD) plus erythropoiesis-stimulating agent (ESA) use was defined as entering advanced chronic kidney disease. The ESA starting date was defined as the first index date, whereas the initiation day of maintenance dialysis was defined as the second index date. The duration between the index dates was analyzed in different medical treatments. Results: There were 10,954 patients analyzed. The combination therapy resulted in the longest duration (n = 2184, median 145 days, p < 0.001) before the dialysis initiation compared with folic acid (n = 5073, median 111 days), pentoxifylline (n = 1119, median 102 days, p = 0.654), and no drug group (control, n = 2578, median 89 days, p < 0.001). Lacking eGFR data and the retrospective nature are important limitations. Conclusions: In patients with advanced CKD on the ESA treatment, the combination of folic acid and pentoxifylline was associated with delayed initiation of hemodialysis.

Analytical Methods for Observational Data to Generate Hypotheses and Inform Clinical Decisions

Randomized controlled trials have been considered the gold standard in informing clinical decision-making while observational studies have generally been utilized to generate hypotheses for future studies. The rising cost of randomized studies along with increased difficulty in accrual has led the clinical community to consider utilizing observational studies to inform clinical decisions. Various statistical methods exist to analyze observational data. Researchers must consider each method carefully, paying specific attention to its ability to answer the hypotheses, while ensuring the underlying assumptions are met. While each has its own strengths and weaknesses, research has shown that each method may yield similar estimates of treatment effect when conducted appropriately. We describe several commonly used analytical methods including their: strengths, weaknesses, and common missteps in order to inform and serve as a reference to the broader oncology community.

Population-Based Observational Studies in Oncology: Proceed With Caution

A principle goal of research in Oncology is to determine the optimal treatment for our patients. This often takes the form of comparing 2 existing therapies to one another to determine which is superior, or to introduce a new therapy and determine if it is superior or noninferior to the existing standard of care. This type of research is termed comparative effectiveness research (CER), and the gold-standard is through the conduct of randomized trials. This is the preferred approach, and the only true methodologic approach that can assign a cause-and-effect relationship between a treatment effect and the observed outcome. An alternative approach that is gaining popularity is the use of population-based registry analysis given that it is quicker, cheaper, and easier to perform. However, there are unavoidable forms of bias and confounding that exist when using observational research to perform CER, and recent evidence suggests that population-based CER often results in erroneous results, and that statistical methods to minimize bias are ineffective to overcome the numerous limitations of these databases. In this article, the strengths and weaknesses of both randomized and observational research will be discussed.

Effectiveness and Safety of Ankle Arthrodesis Versus Arthroplasty: A Prospective Multicenter Study

BACKGROUND

Newer designs and techniques of total ankle arthroplasty (TAA) have challenged the assumption of ankle arthrodesis (AA) as the primary treatment for end-stage ankle arthritis. The objective of this study was to compare physical and mental function, ankle-specific function, pain intensity, and rates of revision surgery and minor complications between these 2 procedures and to explore heterogeneous treatment effects due to age, body mass index (BMI), patient sex, comorbidities, and employment on patients treated by 1 of these 2 methods.

METHODS

This was a multisite prospective cohort study comparing outcomes of surgical treatment of ankle arthritis. Subjects who presented after nonoperative management had failed received either TAA or AA using standard-of-treatment care and rehabilitation. Outcomes included the Foot and Ankle Ability Measure (FAAM), Short Form-36 (SF-36) Physical and Mental Component Summary (PCS and MCS) scores, pain, ankle-related adverse events, and treatment success.

RESULTS

Five hundred and seventeen participants underwent surgery and completed a baseline assessment. At 24 months, the mean improvement in FAAM activities of daily living (ADL) and SF-36 PCS scores was significantly greater in the TAA group than in the AA group, with a difference between groups of 9 points (95% confidence interval [CI] = 3, 15) and 4 points (95% CI = 1, 7), respectively. The crude incidence risks of revision surgery and complications were greater in the AA group; however, these differences were no longer significant after adjusting for age, sex, BMI, and Functional Comorbidity Index (FCI). The treatment success rate was greater after TAA than after AA for those with an FCI of 4 (80% versus 62%) and not fully employed (81% versus 58%) but similar for those with an FCI score of 2 (81% versus 77%) and full-time employment (79% versus 78%).

CONCLUSIONS

At 2-year follow-up, both AA and TAA were effective. Improvement in several patient-reported outcomes was greater after TAA than after AA, without a significant difference in the rates of revision surgery and complications.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Electronic search strategies fail to identify randomized controlled trials (RCTs) in neurosurgery

Randomized controlled trials (RCTs) are the gold standard studies to evaluate the efficacy of therapeutic interventions. Although they are frequently identified through open searches in electronic databases, no studies have evaluated how easy it is to identify RCTs in neurosurgery using electronic search strategies. The present study evaluated the sensitivity and specificity of different search strategies applied to commonly used databases to identify RCTs in neurosurgery. The total number of RCTs in neurosurgery published between 1960 and 2013 was determined through a detailed search involving open keyword searches in PubMed, Cochrane Library and Center for Reviews and Dissemination (CRD) databases, a PubMed search based on clinical entity-related keywords and hand-searches on the reference list of identified articles. The sensitivity and specificity were calculated for the open keyword searches on PubMed, the Cochrane Library and the CRD database and for the Cochrane's HSSS, based on the total number of the identified RCTs. Compared to the total of 1102 RCTs identified, PubMed open search yielded 4660 articles, among which 365 were RCTs (sensitivity: 33.1%; specificity: 7.8%). Cochrane open search yielded 621 among which 36 were RCTs (sensitivity: 3.2%; specificity: 5.8%) and CRD open search returned 78 articles, among which 4 were RCTs (sensitivity: 0.4% sensitivity; specificity: 5.1%). The Cochrane HSSS retrieved 10702 results, among which 340 were RCTs (sensitivity: 30.9%; specificity: 3.2%). Most RCTs in neurosurgery cannot be identified by commonly used search strategies, which emphasizes the need to improve their indexing.

Pramipexole in the treatment of unipolar and bipolar depression. A systematic review and meta-analysis

OBJECTIVE

Several depressed patients do not respond to traditional antidepressants. Our aim was to systematically review the effectiveness and safety of pramipexole in unipolar and bipolar depression.

METHODS

We conducted a systematic review of randomized clinical trials (RCTs) and observational studies on pramipexole for patients with major depressive episodes, following PRISMA guidelines. Our primary outcome measure was treatment response at endpoint. The study protocol was registered on PROSPERO: CRD42018108699.

RESULTS

We found five RCTs, three open-label trials and five observational studies, with 504 participants (57% women; mean age, 45.3 years; mean sample size, 39; median duration of treatment, 8 weeks; mean follow-up duration, 45 weeks; mean maximum dose, 1.62 mg). We found an overall short-term response rate of 52.2% and remission rate of 36.1%, and an overall long-term response rate of 62.1% and remission rate of 39.6%. In RCTs, patients treated with pramipexole had a superior response rate compared with placebo (RR: 1.77; 95% CI: 1.11-2.82) and similar to SSRIs (RR: 0.93; 95% CI: 0.44-1.95). Acceptability and tolerability were good, with nausea being the most frequent side-effect.

CONCLUSION

Our study found some evidence for an effect of pramipexole for the treatment of major depressive episodes.

Hydrogen peroxide skin preparation reduces Cutibacterium acnes in shoulder arthroplasty: a prospective, blinded, controlled trial

BACKGROUND

The purpose of this study was to determine whether preoperative skin preparation with hydrogen peroxide reduces intraoperative culture positivity for Cutibacterium acnes in shoulder arthroplasty.

METHODS

This was a prospective, controlled, parallel/noncrossover, nonrandomized, single-blinded trial registered at clinicaltrials.gov. We included a consecutive series of patients scheduled to undergo primary anatomic or reverse total shoulder arthroplasty. The first group of patients underwent a standard skin preparation and the second group underwent the same preparation with the addition of hydrogen peroxide. We then took skin, dermis, glenohumeral joint, and air (negative control) aerobic and anaerobic culture swabs. We blinded the laboratory analyzing the samples. An a priori power analysis determined that 56 patients would be needed to see a 50% reduction in culture positivity rates. We also conducted a post hoc gender-stratified analysis.

RESULTS

Between January 2017 and October 2018, the authors performed 124 primary shoulder arthroplasties, of which we included 65 and collected samples on 61. There were no demographic differences. There were fewer patients within the peroxide group with triple-positive cultures (skin, dermis, and joint) (0% vs. 19%, P = .024) and positive cultures from the joint (10% vs. 35%, P = .031). In our subgroup analysis, these differences were only significant in males. The vast majority of positive cultures were with C. acnes.

CONCLUSION

Although larger, randomized studies are needed, adding hydrogen peroxide to the preoperative skin preparation may be a low-cost, low-risk method to reduce deep tissue contamination with C. acnes, particularly within males.

Effect Estimates in Randomized Trials and Observational Studies: Comparing Apples With Apples

Effect estimates from randomized trials and observational studies might not be directly comparable because of differences in study design, other than randomization, and in data analysis. We propose a 3-step procedure to facilitate meaningful comparisons of effect estimates from randomized trials and observational studies: 1) harmonization of the study protocols (eligibility criteria, treatment strategies, outcome, start and end of follow-up, causal contrast) so that the studies target the same causal effect, 2) harmonization of the data analysis to estimate the causal effect, and 3) sensitivity analyses to investigate the impact of discrepancies that could not be accounted for in the harmonization process. To illustrate our approach, we compared estimates of the effect of immediate with deferred initiation of antiretroviral therapy in individuals positive for the human immunodeficiency virus from the Strategic Timing of Antiretroviral Therapy (START) randomized trial and the observational HIV-CAUSAL Collaboration.

Real-world insights into risk of developing cardiovascular disease following GnRH agonists versus antagonists for prostate cancer: a methodological protocol to a study using five European databases

One of the more recently investigated adverse long-term side effects of gonadotropin-releasing hormone (GnRH) agonists for prostate cancer (PCa) is cardiovascular disease (CVD). Studies suggest lower risk of CVD following GnRH antagonists (degarelix) than GnRH agonists. This protocol describes precise codes used to extract variables from five European databases for a study that compares risk of CVD following GnRH agonists and antagonists for PCa. PCa men on primary GnRH agonists or antagonists were identified from the UK THIN (The Health Improvement Network) database, National Health Service (NHS) Scotland, Belgian Cancer Registry (BCR), Dutch PHARMO Database Network and French National Database (SNIIRAM). Cohort entry was defined as date of treatment initiation. CVD event was defined as any first incident or fatal CVD after cohort entry. Readcodes in THIN and ICD codes in NHS Scotland, BCR, PHARMO and SNIIRAM were used to extract variables. Risk of Bias in Non-randomised studies of Interventions (ROBINS-I) tool was used to assess the potential risk of biases in this study. 51 572 men with a median follow-up time of 2 years started on GnRH agonists and 2 417 men with a median follow-up time of 1 year started on GnRH antagonists between 2010 and 2017 in the UK, Scotland, Belgium, the Netherlands and France. Data from five countries improved the study power and internal validity required to compare risk of CVD between GnRH agonists and antagonists, the latter being a fairly new drug with limited data in individual countries.

Emulating a Novel Clinical Trial Using Existing Observational Data. Predicting Results of the PreVent Study

Rationale: "Target trial emulation" has been proposed as an observational method to answer comparative effectiveness questions, but it has rarely been attempted concurrently with a randomized clinical trial (RCT).Objectives: We tested the hypothesis that blinded analysts applying target trial emulation to existing observational data could predict the results of an RCT.Methods: PreVent (Preventing Hypoxemia with Manual Ventilation during Endotracheal Intubation) was a multicenter RCT examining the effects of positive-pressure ventilation during tracheal intubation on oxygen saturation and severe hypoxemia. Analysts unaware of PreVent's results used patient-level data from three previous trials evaluating airway management interventions to emulate PreVent's eligibility criteria, randomization procedure, and statistical analysis. After PreVent's release, results of this blinded observational analysis were compared with those of the RCT. Difference-in-differences estimates for comparison of treatment effects between the observational analysis and the PreVent trial are reported on the absolute scale.Results: Using observational data, we were able to emulate PreVent's randomization procedure to produce balanced groups for comparison. The lowest oxygen saturation during intubation was higher in the positive-pressure ventilation group than the no positive-pressure ventilation group in the observational analysis (n = 360; mean difference = 1.8%; 95% confidence interval [CI] = -1.0 to 4.6) and in the PreVent trial (n = 401; mean difference = 3.9%; 95% CI = 1.4 to 6.4), though the observational analysis could not exclude no difference. Difference-in-differences estimates comparing treatment effects showed reasonable agreement for lowest oxygen saturation between the observational analysis and the PreVent trial (mean difference = -2.1%; 95% CI = -5.9 to 1.7). Positive-pressure ventilation resulted in lower rates of severe hypoxemia in both the observational analysis (risk ratio = 0.60; 95% CI = 0.38 to 0.93) and in the PreVent trial (risk ratio = 0.48; 95% CI = 0.30 to 0.77). The absolute reduction in the incidence of severe hypoxemia with positive-pressure ventilation was similar in the observational analysis (9.4%) and the PreVent trial (12.0%), though the difference between these estimates had wide CIs (mean difference = 2.5%; 95% CI = -8.0 to 13.6%).Conclusions: Applying target trial emulation methods to existing observational data for the evaluation of a novel intervention produced results similar to those of a randomized trial. These findings support the use of target trial emulation for comparative effectiveness research.

Insufficient Reporting of Factors Associated With Exercise Referral Scheme Uptake, Attendance, and Adherence: A Systematic Review of Reviews

BACKGROUND

Exercise referral schemes (ERS) are prescribed programs to tackle physical inactivity and associated noncommunicable disease. Inconsistencies in reporting, recording, and delivering ERS make it challenging to identify what works, why, and for whom.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses guided this narrative review of reviews. Electronic databases were searched for systematic reviews of ERS. Inclusion criteria and quality assessed through A Measurement Tool to Assess Systematic Reviews (AMSTAR). Data on uptake, attendance, and adherence were extracted.

RESULTS

Eleven reviews met inclusion criteria. AMSTAR quality was medium. Uptake ranged between 35% and 81%. Groups more likely to take up ERS included (1) females and (2) older adults. Attendance ranged from 12% to 49%. Men were more likely to attend ERS. Effect of medical diagnosis upon uptake and attendance was inconsistent. Exercises prescribed were unreported; therefore, adherence to exercise prescriptions was unreported. The influence of theoretically informed approaches on uptake, attendance, and adherence was generally lacking; however, self-determination, peer support, and supervision were reported as influencing attendance.

CONCLUSIONS

There was insufficient reporting across studies about uptake, attendance, and adherence. Complex interventions such as ERS require consistent definitions, recording, and reporting of these key facets, but this is not evident from the existing literature.

Handheld projective imaging device for near-infrared fluorescence imaging and intraoperative guidance of sentinel lymph node resection

We propose a handheld projective imaging device for orthotopic projection of near-infrared fluorescence images onto target biological tissue at visible wavelengths without any additional visual aid. The device integrates a laser diode light source module, a camera module, a projector, an ultrasonic distance sensor, a Raspberry Pi single-board computer, and a battery module in a rugged handheld unit. It is calibrated at the detected working distance for seamless coregistration between fluorescence emission and projective imaging at the target tissue site. The proposed device is able to achieve a projection resolution higher than 314  μm and a planar projection bias less than 1 mm at a projection field of view of 58  ×  108  mm2 and a working distance of 27 cm. Technical feasibility for projective imaging is verified in an ex vivo model of chicken breast tissue using indocyanine green as a fluorescence agent. Clinical utility for image-guided surgery is demonstrated in a clinical trial where sentinel lymph nodes in breast cancer patients are identified and resected under the guidance of projective imaging. Our ex vivo and in vivo experiments imply the clinical utility of deploying the proposed device for image-guided surgical interventions in resource-limited settings.

Pharmacoepidemiology: Using randomised control trials and observational studies in clinical decision-making

Weighing up sources of evidence is a key skill for clinical decision-makers. Randomised controlled trials (RCTs) and observational studies each have advantages and disadvantages, and in both cases perceived weaknesses can be improved through modifications of design and analysis. In the field of pharmacoepidemiology, RCTs are the best way to determine whether an intervention modifies an outcome being studied, largely because randomisation reduces bias and confounding. Observational studies are useful to investigate whether benefits/harms of a treatment are seen in day-to-day clinical practice in a wider group of patients. Although observational studies, even in a small cohort, can provide very useful clinical evidence, they may also be misleading (as shown by subsequent RCTs), in part because of allocation bias. There is an unmet need for clinicians to become well versed in appraising the study design and statistical analysis of observational pharmacoepidemiology (OP) studies, rather like the medical training already offered for RCT evaluation. This is because OP studies are likely to become more common with the computerisation of healthcare records and increasingly contribute to the evidence base available for clinical decision-making. However, when the results of an RCT conflict with the results of an OP study, the findings of the RCT should be preferred, especially if its findings have been repeated elsewhere. Conversely, OP studies that align with the findings of RCTs can provide rich and useful information to complement that generated by RCTs.

Antioxidants as Adjuvants in Periodontitis Treatment: A Systematic Review and Meta-Analysis

This systematic review with meta-analysis aimed to evaluate the effect of antioxidants as an adjuvant in periodontitis treatment. The following databases were consulted: PubMed, Scopus, Web of Science, Cochrane, Lilacs, OpenGrey, and Google Scholar. Based on the PICO strategy, the inclusion criteria comprised interventional studies including periodontitis patients (participants) treated with conventional therapy and antioxidants (intervention) compared to patients treated only with conventional therapy (control) where the periodontal response (outcome) was evaluated. The risk of bias was evaluated using the Cochrane RoB tool (for randomized studies) and ROBINS-I tool (for nonrandomized studies). Quantitative data were analyzed in five random effects meta-analyses considering the following periodontal parameters: clinical attachment loss (CAL), plaque index (PI), gingival index (GI), bleeding on probing (BOP), and probing depth (PD). After all, the level of certainty was measured with the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) tool. Among the 1884 studies identified, only 15 interventional studies were according to the eligibility criteria and they were included in our review. From them, 4 articles presented a high risk of bias. The meta-analysis showed a statistically significant difference for CAL (SMD 0.29 (0.04, 0.55), p = 0.03, I ² = 13%), PI (SMD 0.41 (0.18, 0.64), p = 0.0005, I ² = 47%), and BOP (SMD 0.55 (0.27, 0.83), p = 0.0001, I ² = 0%). The GRADE tool showed a moderate to high certainty in the quality of evidence depending on the clinical parameter and antioxidants used. These results suggest that the use of antioxidants is an adjunct approach to nonsurgical periodontal therapy which may be helpful in controlling the periodontal status.

Inferior Vena Cava Filters in Stable Patients With Pulmonary Embolism and Heart Failure

Mortality according to the use inferior vena cava (IVC) filters in patients with pulmonary embolism (PE) and heart failure (HF) has been sparsely studied. In the present investigation, we assess whether IVC filters in stable patients with PE and HF reduce mortality. This is a retrospective cohort study of administrative data from the Premier Healthcare Database, 2009 through 2015. Patients aged ≥18 years hospitalized with a primary diagnosis of PE and a discharge diagnosis of HF were identified by International Classification of Diseases-Ninth Revision-Clinical Modification codes. Exclusions were unstable patients (in shock or on a ventilator), patients who underwent pulmonary embolectomy, and patients with co-morbidities. In-hospital all-cause mortality was 102 of 2,423 (4.2%) with an IVC filter compared with 686 of 14,063 (4.9%) without an IVC filter (p = 0.16). Only patients aged >80 years showed a lower in-hospital all-cause mortality with IVC filters, 38 of 933 (4.1%) with an IVC filter compared with 307 of 4,486 (6.8%) without an IVC filter (p = 0.0012). In conclusion, stable patients with PE and HF, if aged >80 years, showed a reduced in-hospital all-cause mortality with IVC filters.

Is Scientific Medical Literature Related to Endometriosis Treatment Evidence-Based? A Systematic Review on Methodological Quality of Randomized Clinical Trials

Background and objectives: Informed decision-making requires the ability to identify and integrate high-quality scientific evidence in daily practice. We aimed to assess whether randomized controlled trials (RCTs) on endometriosis therapy follow methodological criteria corresponding to the RCTs' specific level in the hierarchy of evidence in such details to allow the reproduction and replication of the study. Materials and Methods: Using the keywords "therapy" and "endometriosis" and "efficacy" three bibliographic databases were searched for English written scientific articles published from 1 January 2008 to 3 March 2018. Only the randomized clinical trials (RCTs) were evaluated in terms of whether they provided the appropriate level of scientific evidence, equivalent to level 1, degree 1b in the hierarchy of evidence. A list of criteria to ensure study replication and reproduction, considering CONSORT guideline and MECIR standards, was developed and used to evaluate RCTs' methodological soundness, and scores were granted. Three types of bias, namely selection bias (random sequence generation and allocation concealment), detection bias (blinding of outcome assessment), and attrition bias (incomplete outcome data) were also evaluated. Results: We found 387 articles on endometriosis therapy, of which 38 were RCTs: 30 double-blinded RCTs and 8 open-label RCTs. No article achieved the maximum score according to the evaluated methodological criteria. Even though 73.3% of the double-blinded RCTs had clear title, abstract, introduction, and objectives, only 13.3% provided precise information regarding experimental design and randomization, and also showed a low risk of bias. The blinding method was poorly reported in 43.3% of the double-blinded RCTs, while allocation concealment and random sequence generation were inadequate in 33.3% of them. Conclusions: None of the evaluated RCTs met all the methodological criteria, none had only a low risk of bias and provided sufficient details on methods and randomization to allow for the reproduction and replication of the study. Consequently, the appropriate level of scientific evidence (level 1, degree 1b) could not be granted. On endometriosis therapy, this study evaluated the quality of reporting in RCTs and not the quality of how the studies were performed.

A Longitudinal Study of the Neurologic Safety of Acute Baclofen Use After Spinal Cord Injury

The objective of our study was to determine whether treatment with baclofen is neurologically safe with respect to exposure during recovery from spinal cord injury. We performed a secondary longitudinal analysis of a cohort of adult patients with traumatic acute spinal cord injury. Cumulative baclofen dose was computed over the first 4 weeks following injury from concomitant medication information from a completed clinical trial. The main outcome measure was neurologic status, which was assessed over 52 weeks with "marked recovery" defined as the conversion to higher sensory and motor function. To complete the drug safety profile, drug toxicity was assessed with assays from standard blood work. Multivariable Cox regression was used to compute hazard ratios (HRs) and 95% confidence intervals (CIs). Of the cohort (n = 651), 18% (n = 115) received baclofen within 4 weeks post injury. Baclofen use was associated with higher rates of marked neurologic recovery, even after adjustment for injury severity (HR = 2.1, 95% CI 1.5-3.0 for high dose vs none). Baclofen exposure was not associated with liver or renal side effects. The use of other medications indicated for spasticity was not associated with neurological outcomes. Overall, this longitudinal analysis provides level 3 evidence on the neurologic safety of baclofen and potential beneficial effects on recovery in the early days after acute traumatic spinal cord injury. The usefulness of concomitant medication files from completed clinical trials is highlighted. We also highlight the importance of incorporating logical patient questions and neurological outcomes into research addressing drug safety.

Assessing the Value of Time Series Real-World and Clinical Trial Data vs. Baseline-Only Data in Predicting Responses to Pregabalin Therapy for Patients with Painful Diabetic Peripheral Neuropathy

BACKGROUND AND OBJECTIVE

Treatment challenges necessitate new approaches to customize care to individual patient needs. Integrating data from randomized controlled trials and observational studies may reduce potential covariate biases, yielding information to improve treatment outcomes. The objective of this study was to predict pregabalin responses, in individuals with painful diabetic peripheral neuropathy, by examining time series data (lagged inputs) collected after treatment initiation vs. baseline using microsimulation.

METHODS

The platform simulated pregabalin-treated patients to estimate hypothetical future pain responses over 6 weeks based on six distinct time series regressions with lagged variables as inputs (hereafter termed "time series regressions"). Data were from three randomized controlled trials (N = 398) and an observational study (N = 3159). Regressions were derived after performing a hierarchical cluster analysis with a matched patient dataset from coarsened exact matching. Regressions were validated using unmatched (observational study vs. randomized controlled trial) patients. Predictive implications (of 6-week outcomes) were compared using only baseline vs. 1- to 2-week prior data.

RESULTS

Time series regressions for pain performed well (adjusted R² 0.85-0.91; root mean square error 0.53-0.57); those with only baseline data performed less well (adjusted R² 0.13-0.44; root mean square error 1.11-1.40). Simulated patient distributions yielded positive predictive values for > 50% pain score improvements from baseline for the six clusters (287-777 patients each; range 0.87-0.98).

CONCLUSIONS

Effective prediction of pregabalin response for painful diabetic peripheral neuropathy was accomplished through combining cluster analyses, coarsened exact matching, and time series regressions, reflecting distinct patterns of baseline and "on-treatment" variables. These results advance the understanding of microsimulation to predict patient treatment responses through integration and inter-relationships of multiple, complex, and time-dependent characteristics.

Will registries slow down or accelerate innovation?

The increasing use of regional and national registries of surgical implants has raised concerns that the cost and consequences of these initiatives will adversely influence innovation. The opposite appears to be true, with no evidence of a reduction in overall innovation and an association of increased innovation in countries with more evaluation using registries.

Cite this article: EFORT Open Rev 2019;4 DOI: 10.1302/2058-5241.4.180065

Comparison of mortality and cardiovascular event risk associated with various insulin secretagogues: A nationwide real-world analysis

AIMS

Several insulin secretagogues are widely used to treat diabetes; however, few outcome-based comparative studies have clarified which one of these should be used when indicated. We investigated mortality and cardiovascular event risk associated with optimal forms of insulin secretagogues.

METHODS

In this cohort study using real-world data from the diabetes database of Taiwan's National Health Insurance program, patients with diabetes were enrolled if their initial treatment was glimepiride, gliclazide, glipizide, glyburide, or repaglinide from 1999 to 2013. Each group was propensity score-matched to the glimepiride group before comparison. Primary outcomes were all-cause mortality and the combined cardiovascular event risk of acute myocardial infarction and ischemic stroke. Hazard ratios were calculated by Cox proportional hazard regression models.

RESULTS

There were 66,790, 97,426, 38,806, 92,970, and 11,468 participants in the glimepiride, gliclazide, glipizide, glyburide, and repaglinide groups, respectively. The median follow-up time was 8 years. Glimepiride was associated with the best clinical outcome, showing the lowest mortality and lowest cardiovascular event risk of the five insulin secretagogues. Using patients on glimepiride as the reference group, the adjusted hazard ratios of all-cause mortality and cardiovascular event risk were 1.52 (p < 0.001) and 1.22 (p = 0.005) for gliclazide, 1.42 (p < 0.001) and 1.19 (p = 0.073) for glipizide, 1.43 (p < 0.001) and 1.32 (p < 0.001) for glyburide, and 1.88 (p < 0.001) and 1.69 (p = 0.001) for repaglinide.

CONCLUSIONS

For patients with diabetes taking an insulin secretagogue, glimepiride was associated with the best clinical outcome, showing the lowest mortality and cardiovascular event risk.

Usefulness of Inferior Vena Cava Filters in Stable Patients with Acute Pulmonary Embolism

Retrospective cohort studies using administrative data from national databases or a registry suggest that there are subcategories of stable patients with acute pulmonary embolism who would show a reduced mortality with an inferior vena cava (IVC) filter in addition to anticoagulants. These subcategories are those who underwent pulmonary embolectomy, receiving thrombolytic therapy, suffering recurrent pulmonary embolism while on treatment, hospitalized with solid malignant tumors if aged >60 years, hospitalized with chronic obstructive pulmonary disease (COPD) if aged >50 years, and very elderly (aged >80 years). The following is a review of these studies. It is important to be circumspect in inferring a lower mortality with IVC filters based on comparative effectiveness research that uses national observational data. On the other hand, the likelihood of a randomized controlled trial in any of these subcategories of stable patients is remote. Whether patients are better served by inserting an IVC filter on the basis of retrospective cohort studies, or by withholding IVC filters until a randomized controlled trial can be obtained is a matter for consideration.

Real-World Evidence, Causal Inference, and Machine Learning

The current focus on real world evidence (RWE) is occurring at a time when at least two major trends are converging. First, is the progress made in observational research design and methods over the past decade. Second, the development of numerous large observational healthcare databases around the world is creating repositories of improved data assets to support observational research. OBJECTIVE: This paper examines the implications of the improvements in observational methods and research design, as well as the growing availability of real world data for the quality of RWE. These developments have been very positive. On the other hand, unstructured data, such as medical notes, and the sparcity of data created by merging multiple data assets are not easily handled by traditional health services research statistical methods. In response, machine learning methods are gaining increased traction as potential tools for analyzing massive, complex datasets. CONCLUSIONS: Machine learning methods have traditionally been used for classification and prediction, rather than causal inference. The prediction capabilities of machine learning are valuable by themselves. However, using machine learning for causal inference is still evolving. Machine learning can be used for hypothesis generation, followed by the application of traditional causal methods. But relatively recent developments, such as targeted maximum likelihood methods, are directly integrating machine learning with causal inference.

A safety update on sodium glucose co-transporter 2 inhibitors

Sodium glucose co-transporter 2 inhibitors (SGLT2is) are the first class of glucose lowering agent to be shown to reduce cardiovascular events. They are generally well tolerated with infrequent serious adverse events. The most frequent side effect is genital mycotic infections with candida species that are usually mild to moderate in severity, easily treated and infrequently recur. Urinary tract infections, although common in patients with diabetes, have not been shown to be increased in controlled studies with SGLT2i. Hypoglycaemia can occur when an SGLT2i is added to agents that cause hypoglycaemia, such as insulin or sulphonylureas. Volume depletion and hypotension is infrequent and can be minimized by adjusting diuretic and antihypertensive treatment in patients at risk. Acute renal failure or kidney injury was observed in early observational studies. However, in randomized controlled trials (RCTs) and in more recent observational studies a decreased incidence of acute kidney injury was observed in SGLT2-treated patients compared to those receiving either placebo or another class of glucose lowering agents. An increased incidence of amputation (largely feet and toes) was observed in the RCT with canagliflozin but not with the other SGLT2i. Observational studies have shown either an increased risk of amputation with other agents whereas another study showed no increase. Although the increased risk of amputation is very low, avoidance of SGLT2i in patients at high risk seems prudent. Increased incidence of fractures was observed with canagliflozin but not with SGLT2i nor in a meta-analysis that included canagliflozin, empagliflozin and dapagliflozin. No increased incidence of cancer has been observed in either RCTs or observational studies.

Intrawound Treatment for Prevention of Surgical Site Infections in Instrumented Spinal Surgery: A Systematic Comparative Effectiveness Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

To determine the efficacy of intrawound treatments in reducing deep surgical site infections (SSIs) in instrumented spinal surgery.

METHODS

The electronic databases MEDLINE, EMBASE, and Cochrane were systematically searched for intrawound treatments for the prevention of SSIs in clean instrumented spine surgery. Both randomized controlled trials and comparative cohort studies were included. The results of included studies were pooled for meta-analysis.

RESULTS

After full text- and reference screening, 20 articles were included. There were 2 randomized controlled trials and 18 observational studies. Sixteen studies investigated the use of intrawound antibiotics, and 4 studies investigated the use of intrawound antiseptics. The relative risk of deep SSI for any treatment was 0.26 (95% confidence interval [CI] 0.16-0.44, P < .0001), a significant reduction compared with controls receiving no treatment. For patients treated with local antibiotics the relative risk was 0.29 (95% CI 0.17-0.51, P < .0001), and patients treated with local antiseptics had a relative risk of 0.14 (95% CI 0.05-0.44, P = .0006).

CONCLUSIONS

Both the use of antibiotic and antiseptic intrawound prophylactics was associated with a significant 3 to 7 times reduction of deep SSIs in instrumented spine surgery. No adverse events were reported in the included studies.

Comparison of Population-Based Observational Studies With Randomized Trials in Oncology

PURPOSE

Comparative efficacy research performed using population registries can be subject to significant bias. There is an absence of objective data demonstrating factors that can sufficiently reduce bias and provide accurate results.

METHODS

MEDLINE was searched from January 2000 to October 2016 for observational studies comparing two treatment regimens for any diagnosis of cancer, using SEER, SEER-Medicare, or the National Cancer Database. Reporting quality and statistical methods were assessed using components of the STROBE criteria. Randomized trials comparing the same treatment regimens were identified. Primary outcome was correlation between survival hazard ratio (HR) estimates provided by the observational studies and randomized trials. Secondary outcomes included agreement between matched pairs and predictors of agreement.

RESULTS

Of 3,657 studies reviewed, 350 treatment comparisons met eligibility criteria and were matched to 121 randomized trials. There was no significant correlation between the HR estimates reported by observational studies and randomized trials (concordance correlation coefficient, 0.083; 95% CI, -0.068 to 0.230). Forty percent of matched studies were in agreement regarding treatment effects (κ, 0.037; 95% CI, -0.027 to 0.1), and 62% of the observational study HRs fell within the 95% CIs of the randomized trials. Cancer type, data source, reporting quality, adjustment for age, stage, or comorbidities, use of propensity weighting, instrumental variable or sensitivity analysis, and well-matched study population did not predict agreement.

CONCLUSION

We were unable to identify any modifiable factor present in population-based observational studies that improved agreement with randomized trials. There was no agreement beyond what is expected by chance, regardless of reporting quality or statistical rigor of the observational study. Future work is needed to identify reliable methods for conducting population-based comparative efficacy research.

Clinically, what ought we to believe?

OBJECTIVE:

To question the status of the randomised controlled trial (RCT) in the hierarchy of evidence.

CONCLUSIONS:

The RCT provides important and clinically relevant information, particularly in psychopharmacology. However, and as with other methodologies, RCTs too are flawed and automatic abdication to their conclusions, especially in complex social interventions, is unwise. A clinical example with conflicting and polarising views, each with their evidence base, is described alongside a suggested clinical strategy for resolving differences of opinion.

Operative treatment versus nonoperative treatment of Achilles tendon ruptures: systematic review and meta-analysis

OBJECTIVES

To compare re-rupture rate, complication rate, and functional outcome after operative versus nonoperative treatment of Achilles tendon ruptures; to compare re-rupture rate after early and late full weight bearing; to evaluate re-rupture rate after functional rehabilitation with early range of motion; and to compare effect estimates from randomised controlled trials and observational studies.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed/Medline, Embase, CENTRAL, and CINAHL databases were last searched on 25 April 2018 for studies comparing operative versus nonoperative treatment of Achilles tendon ruptures.

STUDY SELECTION CRITERIA

Randomised controlled trials and observational studies reporting on comparison of operative versus nonoperative treatment of acute Achilles tendon ruptures.

DATA EXTRACTION

Data extraction was performed independently in pairs, by four reviewers, with the use of a predefined data extraction file. Outcomes were pooled using random effects models and presented as risk difference, risk ratio, or mean difference, with 95% confidence interval.

RESULTS

29 studies were included-10 randomised controlled trials and 19 observational studies. The 10 trials included 944 (6%) patients, and the 19 observational studies included 14 918 (94%) patients. A significant reduction in re-ruptures was seen after operative treatment (2.3%) compared with nonoperative treatment (3.9%) (risk difference 1.6%; risk ratio 0.43, 95% confidence interval 0.31 to 0.60; P<0.001; I²=22%). Operative treatment resulted in a significantly higher complication rate than nonoperative treatment (4.9% v 1.6%; risk difference 3.3%; risk ratio 2.76, 1.84 to 4.13; P<0.001; I²=45%). The main difference in complication rate was attributable to the incidence of infection (2.8%) in the operative group. A similar reduction in re-rupture rate in favour of operative treatment was seen after both early and late full weight bearing. No significant difference in re-rupture rate was seen between operative and nonoperative treatment in studies that used accelerated functional rehabilitation with early range of motion (risk ratio 0.60, 0.26 to 1.37; P=0.23; I²=0%). No difference in effect estimates was seen between randomised controlled trials and observational studies.

CONCLUSIONS

This meta-analysis shows that operative treatment of Achilles tendon ruptures reduces the risk of re-rupture compared with nonoperative treatment. However, re-rupture rates are low and differences between treatment groups are small (risk difference 1.6%). Operative treatment results in a higher risk of other complications (risk difference 3.3%). The final decision on the management of acute Achilles tendon ruptures should be based on patient specific factors and shared decision making. This review emphasises the potential benefits of adding high quality observational studies in meta-analyses for the evaluation of objective outcome measures after surgical treatment.

The Profession of Couple, Marital, and Family Therapy (CMFT): Defining Ourselves and Moving Forward

The field of Couple, Marital, and Family Therapy (CMFT) has evolved and strengthened, but we still have work to do when it comes to identity, comprehensive scholarly resources, empirical support, and name brand recognition. We explore the reasons for these challenges and propose ways to address them: embracing the interdisciplinary nature of the field, consistently organizing treatment effectiveness by problem rather than by intervention model, continuing innovation in theory development, and utilizing more diverse and meaningful research methods. This approach provides a more accurate representation of the scope of practice of CMFTs, the range of mental and physical health problems we address, and the depth and extent of the existing research on the effectiveness of relational therapies.

Proton pump inhibitors use and risk of chronic kidney disease in diabetic patients

AIMS

Chronic kidney disease consumes a huge amount of medical resources and proton pump inhibitors may be a potential factor for the increasing prevalence. This population-based cohort study investigates the risk of chronic kidney disease in a diabetic population using proton pump inhibitors in Taiwan.

METHODS

This study is based on a specific diabetic database obtained from the National Health Insurance Research Database. Individuals with a new diagnosis of diabetes from 2002 to 2013 were enrolled. "Exposure" to proton pump inhibitors was defined as at least one prescription and dosage over 180 DDD (defined daily dose) in one year after the index date. A multivariable Cox proportional hazard model and competing-risk regression model were applied.

RESULTS

There were 5994 patients in the final cohort of proton pump inhibitor users and 23,976 patients in the matched controlled cohort based on 1:4 propensity score matching. Compared with no exposure users, PPIs exposure group had more anemia prevalence, anti-hypertension medication and NSAIDs prescriptions. The multivariable Cox proportional hazard model showed that the adjusted hazard ratio of chronic kidney disease was 1.52 (95% CI 1.40-1.65) in diabetic individuals with PPIs exposure, compared with no exposure users.

CONCLUSIONS

Proton pump inhibitors use is associated with 1.52-fold increased risk of chronic kidney disease in diabetic patients when the dosage is over 180 DDD in one year in Taiwan.

Lumbar spinal stenosis: comparison of surgical practice variation and clinical outcome in three national spine registries

BACKGROUND CONTEXT

Decompression surgery for lumbar spinal stenosis (LSS) is the most common spinal procedure in the elderly. To avoid persisting low back pain, adding arthrodesis has been recommended, especially if there is a coexisting degenerative spondylolisthesis. However, this strategy remains controversial, resulting in practice-based variation.

PURPOSE

The present study aimed to evaluate in a pragmatic study if surgical selection criteria and variation in use of arthrodesis in three Scandinavian countries can be linked to variation in treatment effectiveness.

STUDY DESIGN

This is an observational study based on a combined cohort from the national spine registries of Norway, Sweden, and Denmark.

PATIENT SAMPLE

Patients aged 50 and older operated during 2011-2013 for LSS were included.

OUTCOME MEASURES

Patient-Reported Outcome Measures (PROMs): Oswestry Disability Index (ODI) (primary outcome), Numeric Rating Scale (NRS) for leg pain and back pain, and health-related quality of life (Euro-Qol-5D) were reported. Analysis included case-mix adjustment. In addition, we report differences in hospital stay.

METHODS

Analyses of baseline data were done by analysis of variance (ANOVA), chi-square, or logistic regression tests. The comparisons of the mean changes of PROMs at 1-year follow-up between the countries were done by ANOVA (crude) and analysis of covariance (case-mix adjustment).

RESULTS

Out of 14,223 included patients, 10,890 (77%) responded at 1-year follow-up. Apart from fewer smokers in Sweden and higher comorbidity rate in Norway, baseline characteristics were similar. The rate of additional fusion surgery (patients without or with spondylolisthesis) was 11% (4%, 47%) in Norway, 21% (9%, 56%) in Sweden, and 28% (15%, 88%) in Denmark. At 1-year follow-up, the mean improvement for ODI (95% confidence interval) was 18 (17-18) in Norway, 17 (17-18) in Sweden, and 18 (17-19) in Denmark. Patients operated with arthrodesis had prolonged hospital stay.

CONCLUSIONS

Real-life data from three national spine registers showed similar indications for decompression surgery but significant differences in the use of concomitant arthrodesis in Scandinavia. Additional arthrodesis was not associated with better treatment effectiveness.

Agreement between study designs: a systematic review comparing observational studies and randomized trials of surgical treatments for necrotizing enterocolitis

Background: It is unknown whether observational studies comparing laparotomy versus peritoneal drainage for surgical treatment of necrotizing enterocolitis (NEC) in preterm infants differ from randomized controlled trials (RCTs) of the same interventions. Further, in the absence of sufficient RCT evidence, it is uncertain how best to use existing observational data to guide clinical decision making.Methods: We performed a systematic review and meta-analysis of articles comparing laparotomy versus peritoneal drainage for preterm infants with NEC. Two authors independently searched PubMed and the Cochrane Database of Systematic Reviews, from 1 January 1990 to 1 May 2017 and selected articles that: (1) included low birthweight (<2500 g) or preterm (<37-week gestation) infants, (2) compared laparotomy versus peritoneal drainage for NEC, and (3) reported all-cause mortality (primary outcome) in both groups. The same two authors extracted data about study outcomes and about study quality, which was assessed using the Consolidated Standards of Reporting Trials (CONSORT) checklist for reporting of RCTs and Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist for reporting of observational studies. Random-effects meta-analysis was used to generate weighted odds ratios (OR).Results: Twenty-five observational studies and two RCTs met all eligibility criteria. Outcomes were reported for 16,288 patients: 16,103 from observational studies and 185 from RCTs. Meta-analysis of observational studies demonstrated significantly lower mortality after laparotomy, as compared to peritoneal drainage (pooled OR 0.54, 95% CI 0.34-0.84). In contrast, RCTs demonstrated no difference in mortality (pooled OR 0.85, 95% CI 0.47-1.54). In post hoc analyses, observational studies were separated into two subgroups: low versus high quality of reporting, based on the STROBE checklist. Observational studies with low quality of reporting significantly favored laparotomy (pooled OR 0.38, 95% CI 0.18-0.81). In contrast and similar to RCTs, observational studies with high quality of reporting showed no difference in mortality (pooled OR 0.67, 95% CI 0.37-1.19).Conclusions: Neither RCTs nor observational studies with high quality of reporting demonstrate differences in mortality when preterm infants with surgical NEC are managed with laparotomy or peritoneal drainage. While RCTs remain a gold standard for evaluation of therapies, results from high quality observational studies may approximate the results of RCTs and might guide clinical practice until adequate RCT evidence is available.

Various Leisure-Time Physical Activities Associated With Widely Divergent Life Expectancies: The Copenhagen City Heart Study

OBJECTIVE

To evaluate the differential improvements in life expectancy associated with participation in various sports.

PATIENTS AND METHODS

The Copenhagen City Heart Study (CCHS) is a prospective population study that included detailed questionnaires regarding participation in different types of sports and leisure-time physical activity. The 8577 participants were followed for up to 25 years for all-cause mortality from their examination between October 10, 1991, and September 16, 1994, until March 22, 2017. Relative risks were calculated using Cox proportional hazards models with full adjustment for confounding variables.

RESULTS

Multivariable-adjusted life expectancy gains compared with the sedentary group for different sports were as follows: tennis, 9.7 years; badminton, 6.2 years; soccer, 4.7 years; cycling, 3.7 years; swimming, 3.4 years; jogging, 3.2 years; calisthenics, 3.1 years; and health club activities, 1.5 years.

CONCLUSION

Various sports are associated with markedly different improvements in life expectancy. Because this is an observational study, it remains uncertain whether this relationship is causal. Interestingly, the leisure-time sports that inherently involve more social interaction were associated with the best longevity-a finding that warrants further investigation.

Long-Term Effects of Spironolactone on Kidney Function and Hyperkalemia-Associated Hospitalization in Patients with Chronic Kidney Disease

Background: Spironolactone, a non-selective mineralocorticoid receptor antagonist, can protect against cardiac fibrosis and left ventricular dysfunction, and improve endothelial dysfunction and proteinuria. However, the safety and effects of spironolactone on patient-centered cardiovascular and renal endpoints remain unclear. Methods: We identified predialysis stage 3–4 chronic kidney disease (CKD) patients between 2000 and 2013 from the Longitudinal Health Insurance Database 2005 (LHID 2005). The outcomes of interest were end-stage renal disease (ESRD), major adverse cardiovascular events (MACE), hospitalization for heart failure (HHF), hyperkalemia-associated hospitalization (HKAH), all-cause mortality and cardiovascular mortality. The Fine and Gray sub-distribution hazards approach was adopted to adjust for the competing risk of death. Results: After the propensity score matching, 693 patients with stage 3–4 CKD were spironolactone users and 1386 were nonusers. During the follow-up period, spironolactone users had a lower incidence rate for ESRD than spironolactone non-users (39.2 vs. 53.69 per 1000 person-years) and a higher incidence rate for HKAH (54.79 vs. 18.57 per 1000 person-years). The adjusted hazard ratios for ESRD of spironolactone users versus non-users were 0.66 (95% CI, 0.51–0.84; p value < 0.001) and 3.17 (95% CI, 2.41–4.17; p value < 0.001) for HKAH. A dose-response relationship was found between spironolactone use and risk of ESRD and HKAH. There were no statistical differences in MACE, HHF, all-cause mortality and cardiovascular mortality between spironolactone users and non-users. Conclusion: Spironolactone represented a promising treatment option to retard CKD progression to ESRD amongst stage 3–4 CKD patients, but strategic treatments to prevent hyperkalemia should be enforced.