Subcutaneous abatacept for the treatment of rheumatoid arthritis in routine clinical practice in Germany, Austria, and Switzerland: 2-year retention and efficacy by treatment line and serostatus

INTRODUCTION/OBJECTIVES

The ASCORE study on treatment for rheumatoid arthritis (RA) showed better retention and clinical response rates for abatacept as first-line versus later-line therapy. This post hoc analysis of ASCORE assessed 2-year retention, efficacy, and safety of subcutaneous (SC) abatacept in Germany, Austria, and Switzerland.

METHODS

Adults with RA who initiated SC abatacept 125 mg once weekly were assessed. Primary endpoint was abatacept retention rate at 2 years. Secondary endpoints: proportions of patients with low disease activity (LDA)/remission per Disease Activity Score in 28 joints based on erythrocyte sedimentation rate (≤ 3.2), Simplified Disease Activity Index (≤ 11), and Clinical Disease Activity Index (≤ 10). Outcomes were analyzed by treatment line and serostatus.

RESULTS

For the pooled cohort, the 2-year abatacept retention rate was 47.6%; retention was highest in biologic-naïve patients (50.5% [95% confidence interval 44.9, 55.9]). Patients seropositive for both anti-citrullinated protein antibody (ACPA) and rheumatoid factor (RF; + / +) at baseline had a higher 2-year abatacept retention rate than patients with single seropositivity for either APCA or RF or double-seronegativity (- / -), irrespective of treatment line. At 2 years, a higher proportion of patients who were biologic-naïve were in LDA/remission than patients with one or ≥ two prior biologics.

CONCLUSION

A higher proportion of patients with + / + RA (compared with - / - RA) had abatacept retention after 2 years. Early identification of patients with seropositive RA may facilitate a precision-medicine approach to RA treatment, leading to a higher proportion of patients in LDA/remission.

TRIAL REGISTRATION NUMBER

NCT02090556; date registered: March 18, 2014 (retrospectively registered). Key Points • This post hoc analysis of a German-speaking subset of European patients with RA from the global ASCORE study (NCT02090556) showed that retention of SC abatacept within this subset was 47.6%, with good clinical outcomes after 2 years. • Patients with double-seropositive RA (ACPA and RF positive) had higher retention of abatacept than patients with double-seronegative RA (ACPA and RF negative). Retention and clinical responses were highest for patients who were biologic-naïve compared with patients who had one or ≥ two prior biologic treatments. • These real-world data may be useful for clinicians in informing individualized treatment pathways for patients with RA, and fostering superior disease control and clinical outcomes.

The trajectory of clinical responses in patients with early rheumatoid arthritis who achieve sustained remission in response to abatacept: subanalysis of AVERT-2, a randomized phase IIIb study

BACKGROUND

AVERT-2 (a phase IIIb, two-stage study) evaluated abatacept + methotrexate versus methotrexate alone, in methotrexate-naive, anti-citrullinated protein antibody-positive patients with early (≤ 6 months), active RA. This subanalysis investigated whether individual patients who achieved the week 24 Simplified Disease Activity Index (SDAI) remission primary endpoint could sustain remission to 1 year and then maintain it following changes in therapy.

METHODS

During the 56-week induction period (IP), patients were randomized to weekly subcutaneous abatacept 125 mg + methotrexate or abatacept placebo + methotrexate. Patients completing the IP who achieved SDAI remission (≤ 3.3) at weeks 40 and 52 entered a 48-week de-escalation (DE) period. Patients treated with abatacept + methotrexate were re-randomized to continue weekly abatacept + methotrexate, or de-escalate and then withdraw abatacept (after 24 weeks), or receive abatacept monotherapy. Proportions of patients achieving sustained SDAI and Boolean remission, and Disease Activity Score in 28 joints using C-reactive protein (DAS28 [CRP]) < 2.6, were assessed. For patients achieving early sustained SDAI remission at weeks 24/40/52, flow between disease activity categories and individual trajectories was evaluated; flow was also evaluated for later remitters (weeks 40/52 but not week 24).

RESULTS

Among patients treated with abatacept + methotrexate (n/N = 451/752) at IP week 24, 22% achieved SDAI remission, 17% achieved Boolean remission, and 42% achieved DAS28 (CRP) < 2.6; of these, 56%, 58%, and 74%, respectively, sustained a response throughout IP weeks 40/52. Among patients with a sustained response at IP weeks 24/40/52, 82% (14/17) on weekly abatacept + methotrexate, 81% (13/16) on abatacept monotherapy, 63% (12/19) who de-escalated/withdrew abatacept, and 65% (11/17) on abatacept placebo + methotrexate were in SDAI remission at end of the DE period; rates were higher than for later remitters in all arms except abatacept placebo + methotrexate.

CONCLUSIONS

A high proportion of individual patients achieving clinical endpoints at IP week 24 with abatacept + methotrexate sustained their responses through week 52. Of patients achieving early and sustained SDAI remission through 52 weeks, numerically more maintained remission during the DE period if weekly abatacept treatment continued.

TRIAL REGISTRATION

NCT02504268 (ClinicalTrials.gov), registered July 21, 2015.

Sustained Remission and Outcomes with Abatacept plus Methotrexate Following Stepwise Dose De-escalation in Patients with Early Rheumatoid Arthritis

INTRODUCTION

One target of rheumatoid arthritis (RA) treatment is to achieve early sustained remission; over the long term, patients in sustained remission have less structural joint damage and physical disability. We evaluated Simplified Disease Activity Index (SDAI) remission with abatacept + methotrexate versus abatacept placebo + methotrexate and impact of de-escalation (DE) in anti-citrullinated protein antibody (ACPA)-positive patients with early RA.

METHODS

The phase IIIb, randomized, AVERT-2 two-stage study (NCT02504268) evaluated weekly abatacept + methotrexate versus abatacept placebo + methotrexate.

PRIMARY ENDPOINT

SDAI remission (≤ 3.3) at week 24. Pre-planned exploratory endpoint: maintenance of remission in patients with sustained remission (weeks 40 and 52) who, from week 56 for 48 weeks (DE period), (1) continued combination abatacept + methotrexate, (2) tapered abatacept to every other week (EOW) + methotrexate for 24 weeks with subsequent abatacept withdrawal (abatacept placebo + methotrexate), or (3) withdrew methotrexate (abatacept monotherapy).

RESULTS

Primary study endpoint was not met: 21.3% (48/225) of patients in the combination and 16.0% (24/150) in the abatacept placebo + methotrexate arm achieved SDAI remission at week 24 (p = 0.2359). There were numerical differences favoring combination therapy in clinical assessments, patient-reported outcomes (PROs) and week 52 radiographic non-progression. After week 56, 147 patients in sustained remission with abatacept + methotrexate were randomized (combination, n = 50; DE/withdrawal, n = 50; abatacept monotherapy, n = 47) and entered DE. At DE week 48, SDAI remission (74%) and PRO improvements were mostly maintained with continued combination therapy; lower remission rates were observed with abatacept placebo + methotrexate (48.0%) and with abatacept monotherapy (57.4%). Before withdrawal, de-escalating to abatacept EOW + methotrexate preserved remission.

CONCLUSIONS

The stringent primary endpoint was not met. However, in patients achieving sustained SDAI remission, numerically more maintained remission with continued abatacept + methotrexate versus abatacept monotherapy or withdrawal.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT02504268. Video abstract (MP4 62241 KB).

Baseline serum levels of cross-linked carboxy-terminal telopeptide of type I collagen predict abatacept treatment response in methotrexate-naive, anticitrullinated protein antibody-positive patients with early rheumatoid arthritis

OBJECTIVE

To investigate correlations between biomarkers of bone remodelling and extracellular matrix turnover with baseline disease activity and treatment response in patients with early rheumatoid arthritis (RA).

METHODS

Assessing Very Early Rheumatoid arthritis Treatment-2 (AVERT-2; NCT02504268) included disease-modifying antirheumatic drug-naive, anti-citrullinated protein antibody (ACPA)-positive patients randomised to weekly subcutaneous abatacept+methotrexate (MTX) or abatacept placebo+MTX for 56 weeks. This post hoc exploratory subanalysis assessed the association between baseline disease activity and eight biomarkers (Spearman's correlation coefficient), and whether baseline biomarkers (continuous or categorical variables) could predict treatment response at weeks 24 and 52 (logistic regression).

RESULTS

Patient characteristics were similar between overall (n=752) and biomarker subgroup (n=535) populations and across treatments. At baseline, neoepitopes of matrix metalloproteinase-mediated degradation products of types III and IV collagen and of C reactive protein (CRP) showed the greatest correlations with disease activity; cross-linked carboxy-terminal telopeptide of type I collagen (CTX-I) showed weak correlation. Only CTX-I predicted treatment response; baseline CTX-I levels were significantly associated with achieving Simplified Disease Activity Index remission and Disease Activity Score in 28 joints (DAS28 (CRP)) <2.6 (weeks 24 and 52), and American College of Rheumatology 70 response (week 52), in patients treated with abatacept+MTX but not abatacept placebo+MTX. CTX-I predicted significant differential response between arms for DAS28 (CRP) <2.6 (week 24). Treatment differences were greater for abatacept+MTX in patients with medium/high versus low baseline CTX-I.

CONCLUSION

In MTX-naive, ACPA-positive patients with early RA, baseline CTX-I predicted treatment response to abatacept+MTX but not abatacept placebo+MTX.

ACPA-negative and ACPA-positive RA patients achieving disease resolution demonstrate distinct patterns of MRI-detected joint-inflammation

OBJECTIVES

Although sustained DMARD-free remission (SDFR; sustained absence of clinical-synovitis after DMARD-discontinuation) is increasingly achievable in RA, prevalence differs between ACPA-negative (40%) and ACPA-positive RA (5-10%). Additionally, early DAS remission (DAS4months<1.6) is associated with achieving SDFR in ACPA-negative, but not in ACPA-positive RA. Based on these differences, we hypothesized that longitudinal patterns of local tissue inflammation (synovitis/tenosynovitis/osteitis) also differ between ACPA-negative and ACPA-positive RA patients achieving SDFR. With the ultimate aim being to increase understanding of disease resolution in RA, we studied MRI-detected joint inflammation over time in relation to SDFR development in ACPA-positive RA and ACPA-negative RA.

METHODS

A total of 198 RA patients (94 ACPA-negative, 104 ACPA-positive) underwent repeated MRIs (0/4/12/24 months) and were followed on SDFR development. The course of MRI-detected total inflammation, and synovitis/tenosynovitis/osteitis individually were compared between RA patients who did and did not achieve SDFR, using Poisson mixed models. In total, 174 ACPA-positive RA patients from the AVERT-1 were studied as ACPA-positive validation population.

RESULTS

In ACPA-negative RA, baseline MRI-detected inflammation levels of patients achieving SDFR were similar to patients without SDFR but declined 2.0 times stronger in the first year of DMARD treatment [IRR 0.50 (95% CI; 0.32, 0.77); P < 0.01]. This stronger decline was seen in tenosynovitis/synovitis/osteitis. In contrast, ACPA-positive RA-patients achieving SDFR, had already lower inflammation levels (especially synovitis/osteitis) at disease presentation [IRR 0.45 (95% CI; 0.24, 0.86); P = 0.02] compared with patients without SDFR, and remained lower during subsequent follow-up (P = 0.02). Similar results were found in the ACPA-positive validation population.

CONCLUSION

Compared with RA patients without disease resolution, ACPA-positive RA patients achieving SDFR have less severe joint inflammation from diagnosis onwards, while ACPA-negative RA patients present with similar inflammation levels but demonstrate a stronger decline in the first year of DMARD therapy. These different trajectories suggest different mechanisms underlying resolution of RA chronicity in both RA subsets.

Implementation of the OMERACT Psoriatic Arthritis Magnetic Resonance Imaging Scoring System in a randomized phase IIb study of abatacept in psoriatic arthritis

OBJECTIVES

To investigate if the OMERACT PsA MRI Scoring System (PsAMRIS), including a novel total inflammation score, shows sensitivity to change with an agent (abatacept) known to impact clinical outcomes in PsA.

METHODS

We performed a post hoc analysis of a randomized phase IIb study of abatacept in patients with PsA and inadequate DMARD response. Participants received one of three abatacept dosing regimens [ABA3, ABA10 or ABA30/10 mg/kg (30 mg/kg switched to 10 mg/kg after two doses)] or placebo until day 169, then ABA10 through day 365. MRIs at baseline and days 85, 169 and 365 were centrally evaluated by two readers blinded to chronological order and treatment arm. Synovitis, osteitis, tenosynovitis, periarticular inflammation, bone erosions, joint space narrowing and bone proliferation were assessed using the PsAMRIS. A novel total inflammation score was tested.

RESULTS

MRIs for 123 patients were included. On day 169, ABA10 and ABA30/10 significantly reduced MRI synovitis and tenosynovitis, respectively, vs placebo [differences -0.966 (P = 0.039) and -1.652 (P = 0.014), respectively]. Synovitis in the placebo group increased non-significantly from baseline to day 169, total inflammation and tenosynovitis decreased non-significantly and all measures improved significantly after a switch to ABA10 [-1.019, -0.940, -2.275 (P < 0.05), respectively, day 365 vs day 169]. Structural outcomes changed minimally across groups.

CONCLUSION

Adults with PsA receiving ABA10 and ABA30/10 demonstrated significant resolution of inflammatory components of disease, confirmed by MRI, with synovitis and tenosynovitis improvements consistent with previously reported clinical responses for these doses. Results indicate that a reduction in OMERACT PsAMRIS inflammation scores may provide proof of tissue-level efficacy in PsA clinical trials.

REGISTRATION

ClinicalTrials.gov (https://clinicaltrials.gov), NCT00534313.

Carbonyl Posttranslational Modification Associated With Early-Onset Type 1 Diabetes Autoimmunity

Inflammation and oxidative stress in pancreatic islets amplify the appearance of various posttranslational modifications to self-proteins. In this study, we identified a select group of carbonylated islet proteins arising before the onset of hyperglycemia in NOD mice. Of interest, we identified carbonyl modification of the prolyl-4-hydroxylase β subunit (P4Hb) that is responsible for proinsulin folding and trafficking as an autoantigen in both human and murine type 1 diabetes. We found that carbonylated P4Hb is amplified in stressed islets coincident with decreased glucose-stimulated insulin secretion and altered proinsulin-to-insulin ratios. Autoantibodies against P4Hb were detected in prediabetic NOD mice and in early human type 1 diabetes prior to the onset of anti-insulin autoimmunity. Moreover, we identify autoreactive CD4+ T-cell responses toward carbonyl-P4Hb epitopes in the circulation of patients with type 1 diabetes. Our studies provide mechanistic insight into the pathways of proinsulin metabolism and in creating autoantigenic forms of insulin in type 1 diabetes.

Retention of subcutaneous abatacept for the treatment of rheumatoid arthritis: real-world results from the ASCORE study: an international 2-year observational study

OBJECTIVES

To evaluate retention, efficacy, and safety of subcutaneous (SC) abatacept over 2 years in patients with moderate-to-severe RA in the Abatacept SubCutaneOus in Routine clinical practicE (ASCORE) study.

METHODS

Patients with RA who initiated SC abatacept 125 mg once weekly were enrolled in the international, observational, prospective multicentre ASCORE study into biologic-naïve or ≥ 1 prior biologic failure cohorts.

PRIMARY ENDPOINT

abatacept retention rate at 2 years. Secondary endpoints: proportion of patients with good/moderate EULAR response rates based on DAS28 (ESR), low disease activity and/or remission according to DAS28 (ESR; ≤ 3.2/ < 2.6), SDAI (≤ 11/ ≤ 3.3), CDAI (≤ 10/ ≤ 2.8), and Boolean criteria. Retention rate by baseline serostatus was evaluated post hoc.

RESULTS

Overall, 47% of patients remained on abatacept for 2 years, irrespective of treatment line. Higher abatacept retention rates were associated with lower prior biologic exposure. Generally, clinical outcomes showed that the proportion of patients with low disease activity/remission was higher in biologic-naïve patients (vs biologic-failure) and similar in those with 1 and ≥ 2 prior biologic failures. In patients on treatment at 2 years, good/moderate EULAR response rates of ~ 80% were consistently noted irrespective of prior biologic exposure. Across treatment lines, retention was greater in patients with seropositive (vs seronegative) RA. Patients with rheumatoid factor/anti-citrullinated protein antibody single-positive RA who were bio-naïve had higher retention than patients who were bio-experienced.

CONCLUSIONS

In the ASCORE study, SC abatacept retention was 47% at 2 years with good clinical outcomes and was well-tolerated in the real-world setting. Abatacept retention and clinical response rates were higher in patients who received abatacept as an earlier- versus later-line biologic drug treatment and in those with seropositive RA.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02090556.

Baseline Anti-Citrullinated Protein Antibody Status and Response to Abatacept or Non-TNFi Biologic/Targeted-Synthetic DMARDs: US Observational Study of Patients with RA

INTRODUCTION

Patients with rheumatoid arthritis (RA) may respond to treatments differently based on their underlying serology and biomarker status, but real-world data comparing treatment responses to abatacept versus other non-TNFi biologic or targeted-synthetic DMARDs by anti-citrullinated protein antibody (ACPA) status remain limited. We assessed the association between ACPA status and response to treatment in patients with RA.

METHODS

Adults from CorEvitas' RA Registry were identified who initiated abatacept, rituximab, tocilizumab, or tofacitinib, and had ACPA measured at/prior to treatment initiation and at the 6-month follow-up visit. Three cohorts were included: abatacept/rituximab (2006-2019), abatacept/tocilizumab (2010-2019), and abatacept/tofacitinib (2012-2019). Patient characteristics at initiation were compared by ACPA status (positive [+], anti-cyclic citrullinated peptide-2 [anti-CCP2] ≥ 20 U/ml; negative [-], anti-CCP2 < 20 U/ml). Outcomes over 6 months: changes in Clinical Disease Activity Index (CDAI), modified Health Assessment Questionnaire (mHAQ), patient global assessment (PGA) scores, and proportion of patients achieving a clinical response. Adjusted mean differences and odds ratios were estimated using mixed-effects linear regression models.

RESULTS

Overall, 982 abatacept, 246 rituximab, 404 tocilizumab, and 429 tofacitinib initiators were identified. ACPA+ (vs. ACPA-) patients had longer disease duration and more erosive disease. During most time periods adjusted mean changes in CDAI, mHAQ, and PGA scores and the proportion of patients achieving a clinical response were significantly higher for ACPA+ versus ACPA- patients initiating abatacept. Adjusted mean change in PGA score and patient fatigue were significantly higher for ACPA+ versus ACPA- patients initiating rituximab. No significant differences were seen by ACPA status for patients initiating tocilizumab or tofacitinib.

CONCLUSIONS

Patients who initiated abatacept or rituximab and were ACPA+ had a greater clinical response at 6-month follow-up post index compared to patients who were ACPA- treated with the same biologic.

Differential Changes in ACPA Fine Specificity and Gene Expression in a Randomized Trial of Abatacept and Adalimumab in Rheumatoid Arthritis

Introduction

The biologics abatacept and adalimumab have different mechanisms of action (MoAs). We analyzed data from patients with rheumatoid arthritis treated in AMPLE (NCT00929864) to explore the pharmacodynamic effects of abatacept or adalimumab on anti-citrullinated protein antibodies (ACPAs) and gene expression.

Methods

AMPLE was a phase IIIb, 2-year, randomized, head-to-head trial of abatacept versus adalimumab. Post hoc analyses of baseline anti-cyclic citrullinated peptide-2 (anti-CCP2, an ACPA surrogate) positive (+) status and ACPA fine-specificity profiles over time, as well as transcriptional profiling (peripheral whole blood), were performed.

Results

Of 646 patients treated (abatacept, n = 318; adalimumab, n = 328), ACPA and gene expression data were available from 508 and 566 patients, respectively. In anti-CCP2+ patients (n = 388), baseline fine specificities for most ACPAs were highly correlated; over 2 years, levels decreased with abatacept but not adalimumab. By year 2, expression of genes associated with T cell co-stimulation and antibody production was lower for abatacept versus adalimumab; expression of genes associated with proinflammatory signaling was lower for adalimumab versus abatacept. Treatment modulated the expression of T- and B-cell gene signatures, with differences in CD8+ T cells, activated T cells, plasma cells, B cells, natural killer cells (all lower with abatacept versus adalimumab), and polymorphonuclear leukocytes (higher with abatacept versus adalimumab).

Conclusions

In AMPLE, despite similar clinical outcomes, data showed that pharmacodynamic/genetic changes after 2 years of abatacept or adalimumab were consistent with drug MoAs. Further assessment of the relationship between such changes and clinical outcomes, including prediction of response, is warranted.

Trial Registration

ClinicalTrials.gov identifier, NCT00929864.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-021-00404-x.

The Utilization and Diagnostic Yield of Upper Endoscopy for Evaluation of Gastrointestinal Symptoms Within the First Year After Liver Transplantation

Background Gastrointestinal (GI) symptoms impact quality of life and increase health care utilization after liver transplantation (LTx). Esophagogastroduodenoscopy (EGD) is commonly used to investigate these symptoms. Aims The aim of this study was to investigate the diagnostic yield and utilization of EGD after LTx for common GI symptoms. Methods This single-center retrospective cohort study was conducted at a large liver transplant center and included all adults who underwent EGD within the first year after receiving LTx between January 1, 2015, and December 31, 2016. Biliary procedures were excluded. Results Of 437 patients who underwent LTx during the study period, 64 (15%) underwent EGD for the evaluation of GI symptoms within the first year of transplantation. After applying exclusion criteria, 57 (13%) cases were analyzed. GI hemorrhage (hematemesis/melena) was the most common reason (4%; n=18) for evaluation with EGD followed by nausea/anorexia (3%; n=12). Symptoms were investigated with EGD, including epigastric/abdominal pain (2%; n=9), dysphagia/odynophagia (2%; n=8), anemia (1%; n=5), diarrhea (1%; n=4), and heartburn (0.2%; n=1). The diagnostic yield of EGD was highest with GI hemorrhage (83%) followed by dysphagia/odynophagia (75%). EGD diagnostic yield was lower for the other symptoms, ranging from 0% to 25%. Conclusions EGD was commonly utilized within the first year of LTx, with the highest diagnostic yields for GI hemorrhage and dysphagia/odynophagia. Because of the low diagnostic yield of EGD for other symptoms, we recommend a careful selection of patients for EGD following LTx.

Disease activity and patient-reported outcomes in patients with rheumatoid arthritis and Sjögren’s syndrome enrolled in a large observational US registry

The objective of this study was to compare rheumatoid arthritis (RA) disease activity and patient-reported outcomes (PROs) in a national sample of patients with RA with/without Sjögren’s syndrome (SS). Adults with RA from a large observational US registry (Corrona RA) with known SS status between 22 April 2010 and 31 July 2018 and a visit 12 (± 3) months after index date were identified (n = 36,256/52,757). SS status: determined from a yes/no variable reported at enrolment into the Corrona RA registry and follow-up visits. Index date: date that SS status was recorded (yes/no). Patients received biologic or targeted synthetic disease-modifying antirheumatic drugs as part of standard care. Patients with RA only were followed for ≥ 12 months to confirm the absence of SS. Patients were frequency- and propensity-score matched (PSM) 1:1 and stratified by disease duration and treatment response-associated variables, respectively. Clinical Disease Activity Index (CDAI) and PROs 12 months after index visit were compared in patients with and without SS. Baseline characteristics in 283 pairs of PSM patients were balanced. Mean change in CDAI score was numerically lower in patients with RA and SS than patients with RA only (8.8 vs 9.3). Reductions in PROs of pain, fatigue and stiffness were two- to threefold lower for patients with RA and SS versus RA only. Reductions in RA disease activity and RA-related PROs were lower in patients with RA and SS versus those with RA only. Our data indicate that SS adds to treatment challenges; physicians may wish to consider SS status when managing patients with RA.

A Prospective Multicenter Study Evaluating Endoscopy Competence Among Gastroenterology Trainees in the Era of the Next Accreditation System

PURPOSE

The Next Accreditation System requires training programs to demonstrate competence among trainees. Within gastroenterology (GI), there are limited data describing learning curves and structured assessment of competence in esophagogastroduodenoscopy (EGD) and colonoscopy. In this study, the authors aimed to demonstrate the feasibility of a centralized feedback system to assess endoscopy learning curves among GI trainees in EGD and colonoscopy.

METHOD

During academic year 2016-2017, the authors performed a prospective multicenter cohort study, inviting participants from multiple GI training programs. Trainee technical and cognitive skills were assessed using a validated competence assessment tool. An integrated, comprehensive data collection and reporting system was created to apply cumulative sum analysis to generate learning curves that were shared with program directors and trainees on a quarterly basis.

RESULTS

Out of 183 fellowships invited, 129 trainees from 12 GI fellowships participated, with an overall trainee participation rate of 72.1% (93/129); the highest participation level was among first-year trainees (90.9%; 80/88), and the lowest was among third-year trainees (51.2%; 27/53). In all, 1,385 EGDs and 1,293 colonoscopies were assessed. On aggregate learning curve analysis, third-year trainees achieved competence in overall technical and cognitive skills, while first- and second-year trainees demonstrated the need for ongoing supervision and training in the majority of technical and cognitive skills.

CONCLUSIONS

This study demonstrated the feasibility of using a centralized feedback system for the evaluation and documentation of trainee performance in EGD and colonoscopy. Furthermore, third-year trainees achieved competence in both endoscopic procedures, validating the effectiveness of current training programs.

Association among anti-citrullinated protein antibody status, erosive disease and healthcare resource utilization in patients with rheumatoid arthritis

Objective: To characterize the rate of healthcare resource utilization (HCRU) between anti-cyclic citrullinated peptide (CCP; a surrogate for anti-citrullinated protein antibodies [ACPAs]) positive (+) patients with rheumatoid arthritis (RA), either with or without erosions, who initiated biologic disease-modifying antirheumatic drug (bDMARD) treatment.Methods: Data from the Corrona RA registry, a prospective registry of adult patients with RA from 177 sites across 42 states in the US, were analyzed. Annual rates of HCRU (measured based on rates of all-cause hospitalization, joint surgery, imaging procedures and use of assistive devices) were estimated in anti-CCP + patients with and without erosions following bDMARD initiation using a Poisson regression model.Results: Among the 3333 patients with known anti-CCP and erosion status and 12-month post-bDMARD follow-up information in the Corrona registry, 2047 were anti-CCP + and included in this analysis; 868 with and 1179 without erosions. Baseline characteristics were generally well balanced between patients with and without erosions; however, those with erosions had a longer mean RA duration and a higher prior DMARD use. Over 12 months, among anti-CCP + patients, those with erosions had significantly higher rates of all HCRU, except joint surgery, than those without erosions. Age-adjusted risk ratios (95% confidence interval) were as follows: all-cause hospitalization, 1.47 (1.14, 1.90); all-cause imaging, 1.25 (1.03, 1.53); and assistive device use 1.12 (1.00, 1.25). The rate of joint surgery visits was also numerically higher in patients with versus without erosion.Conclusions: ACPA seropositivity with erosive disease was associated with higher rates of HCRU compared with seropositivity without erosions. These findings suggest that providers may want to manage anti-CCP + patients aggressively to achieve better disease control to prevent the development of erosions and the associated increase in HCRU.

Abatacept retention and clinical outcomes in Austrian patients with rheumatoid arthritis: real-world data from the 2-year ACTION study

BACKGROUND

AbataCepT In rOutiNe clinical practice (ACTION; NCT02109666) was a 2-year international observational study of patients with moderate to severe rheumatoid arthritis.

METHODS

Baseline characteristics, abatacept retention rates, and clinical outcomes were compared by treatment line in the Austrian cohort of ACTION.

RESULTS

Of 100 patients enrolled in Austria, 98 (98.0%) were evaluable: 33/98 (33.7%) biologic naïve and 65/98 (66.3%) with ≥1 prior biologic failure. At baseline, biologic-naïve patients had shorter disease duration and lower concomitant corticosteroid use than biologic-failure patients. Overall crude abatacept retention rate was 60.5% and retention rate was higher in biologic-naïve (65.1%) versus biologic-failure (58.0%) patients. Good/moderate EULAR (European League Against Rheumatism) response rates were 85.7% in biologic-naïve and 100% in biologic-failure patients.

CONCLUSIONS

In the Austrian cohort of ACTION, overall abatacept retention at 2 years was high, with higher retention rates in patients receiving abatacept as an earlier treatment line. Good/moderate EULAR response rate was higher in biologic-failure than in biologic-naïve patients.

Supplementing Claims Data with Electronic Medical Records to Improve Estimation and Classification of Rheumatoid Arthritis Disease Activity: A Machine Learning Approach

Objective

Previous attempts to estimate rheumatoid arthritis (RA) disease activity using claims data only did not yield high performance. We aimed to assess whether supplementing claims data with readily available electronic medical record (EMR) data might result in improvement.

Methods

We used a subset of the Brigham and Women's Hospital Rheumatoid Arthritis Sequential Study (BRASS) that had linked Medicare claims. The disease activity score in 28 joints with C-reactive protein (DAS28-CRP) was considered the gold standard of measure. Variables in the linked Medicare claims, as well as EMR recorded in the preceding one-year period were used as potential explanatory variables. We constructed three models: "Claims-Only," "Claims + Medications," and "Claims + Medications + Labs (laboratory data from EMR). We selected variables via adaptive LASSO. Model performance was measured with adjusted R2 for continuous DAS28-CRP and C-statistics for binary category classification (high/moderate vs low disease activity/remission).

Results

We identified 300 patients with laboratory data and linked Medicare claims. The mean age was 68 years and 80% were female. The mean (SD) DAS28-CRP was 3.6 (1.6) and 51% had high or moderate DAS28-CRP. For the continuous estimation, the adjusted R2 was 0.02 for Claims-Only, 0.09 for Claims + Medications, and 0.18 for Claims + Medications + Labs. The C-statistics for discriminating the binary categories were 0.61 for Claims-Only, 0.68 for Claims + Medications, and 0.76 for Claims + Medications + Labs.

Conclusion

Adding EMR-derived variables to claims-derived variables resulted in modest improvement. Even with EMR variables, we were unable to estimate continuous DAS28-CRP satisfactorily. However, in claims-EMR models, we were able to discriminate between binary categories of disease activity with reasonable accuracy.

Performance comparison of 159 Thoroughbred racehorses and matched cohorts before and after desmotomy of the interspinous ligament

Racehorses may perform poorly because of impinging dorsal spinous processes (DSPs) of the thoracolumbar vertebrae. No study has looked objectively at the long-term outcome of racehorses undergoing desmotomy of the interspinous ligament as a treatment for horses with poor performance caused by impinging DSPs. The aim of this study was to examine objectively, by using pre-operative and post-operative racing records, the effectiveness of desmotomy of the interspinous ligament (DISL) in improving the performance of racehorses with impinging DSPs. Medical records of all horses undergoing desmotomy of one or more interspinous ligaments at a referral equine hospital, between February 2015 and September 2016, were reviewed. The study was confined to Thoroughbred racehorses with sufficient historical information and racetrack data to allow their racing performances be compared to that of matched controls. Matched controls were of the same age, sex, and racing type and were trained at the same time by the same trainer as those undergoing desmotomy. The time to follow-up was at least 12 months. Of the 6545 horses presented for poor performance or lameness during the study period, 236 horses (3.6%) underwent desmotomy of one or more interspinous ligaments, and of these, 159 met the inclusion criteria. Horses undergoing desmotomy had significantly better improvement in racing performance than did matched controls. Eight horses developed unilateral neurogenic atrophy of epaxial musculature. DISL between impinging DSPs can improve the performance of racehorses experiencing from poor performance caused by pain resulting from the impinging processes.

Economic Evaluation of Anticyclic Citrullinated Peptide Positivity in Rheumatoid Arthritis

BACKGROUND

Anticyclic citrullinated peptide (anti-CCP) positivity may be a strong predictor of joint erosion and a potential biomarker for guiding treatment decisions for rheumatoid arthritis (RA). However, limited studies are currently available on the effect of anti-CCP positivity on health care utilization and/or medical costs of RA patients.

OBJECTIVE

To investigate short-term and long-term direct health care expenditures associated with anti-CCP positivity in newly diagnosed RA patients.

METHODS

A retrospective cohort study was conducted in adult RA patients within a U.S. integrated health care delivery system (January 1, 2007-June 30, 2015). Patients were required to have 2 RA diagnoses and treatment with a conventional or biologic disease-modifying antirheumatic drug (DMARD) within 12 months. The first RA diagnosis date was labeled as the index date, and patients were followed until they left the health plan, died, or reached the end of the study period. Patient demographics, anti-CCP results, comorbid conditions, and health care resource utilization during baseline (12 months before the index date) and follow-up periods were collected. Nationally recognized direct medical costs were assigned to health care utilization to calculate health care costs in 2015 U.S. dollars. The baseline differences between anti-CCP positivity and negativity and differences in censoring during follow-up were addressed using propensity scores. The mean differences in costs were estimated using recycled prediction methods.

RESULTS

2,448 newly diagnosed RA patients were identified and followed for a median of 3.7 years (range = 1-8 years). At baseline, 65.8% of patients were anti-CCP positive. Anti-CCP-positive patients had fewer comorbid conditions at baseline. During the first 12 months of follow-up, median (interquartile range) total health care expenditures for anti-CCP-positive and anti-CCP-negative patients were $6,200 ($3,563-$13,260) and $7,022 ($3,885-$12,995), respectively. After adjusting for baseline differences, total incremental mean cost associated with anti-CCP positivity during the first 12 months was estimated to be $2,163 per patient (P = 0.001). The annual incremental costs in anti-CCP-positive patients became progressively larger over time, from $2,163 during the first year to $5,062 during the fourth year. Anti-CCP positivity was associated with higher prescription, laboratory testing, and rheumatologist utilization. A higher percentage of anti-CCP-positive patients received 1 or more biologic DMARDs (11.6% for anti-CCP-positive vs. 5.7% for anti-CCP negative; P < 0.001) compared with anti-CCP-negative patients during the 12-month follow-up, which resulted in $2,499 in incremental prescription costs (P < 0.001). Total additional burden associated with anti-CCP positivity during the first 4 years was estimated to be $14,089 per patient.

CONCLUSIONS

In newly diagnosed RA patients, higher economic burden associated with anti-CCP positivity was mainly driven by prescription costs.

DISCLOSURES

This research and manuscript were funded by Bristol-Myers Squibb (BMS). Alemao and Connolly are employees and shareholders of BMS and participated in the design of the study, interpretation of the data, review/revision of the manuscript, and approval of the final version of the manuscript. An and Cheetham received a grant from BMS for this research. At the time of this study, An was employed by Western University of Health Sciences, and Cheetham was employed by Kaiser Permanente Southern California. Bider-Canfield, Kang, and Lin have nothing to disclose. Some study results were presented as a poster at the American College of Rheumatology Annual Meeting; November 5, 2017; San Diego, CA, and at the International Society for Pharmacoeconomics and Outcomes Research Meeting; May 19, 2018; Baltimore, MD.

Do Poor Prognostic Factors in Rheumatoid Arthritis Affect Treatment Choices and Outcomes? Analysis of a US Rheumatoid Arthritis Registry

OBJECTIVE

To characterize patients with rheumatoid arthritis (RA) by number of poor prognostic factors (PPF: functional limitation, extraarticular disease, seropositivity, erosions) and evaluate treatment acceleration, clinical outcomes, and work status over 12 months by number of PPF.

METHODS

Using the Corrona RA registry (January 2005-December 2015), biologic-naive patients with diagnosed RA having 12-month (± 3 mos) followup were identified and categorized by PPF (0-1, 2, ≥ 3). Changes in medication, Clinical Disease Activity Index (CDAI), and work status (baseline-12 mos) were evaluated using linear and logistic regression models.

RESULTS

There were 3458 patients who met the selection criteria: 1489 (43.1%), 1214 (35.1%), and 755 (21.8%) had 0-1, 2, or ≥ 3 PPF, respectively. At baseline, patients with ≥ 3 PPF were older, and had longer RA duration and higher CDAI versus those with 0-1 PPF. In 0-1, 2, and ≥ 3 PPF groups, respectively, 20.9%, 23.2%, and 26.5% of patients received ≥ 1 biologic (p = 0.011). Biologic/targeted synthetic disease-modifying antirheumatic drug (tsDMARD) use was similar in patients with/without PPF (p = 0.57). After adjusting for baseline CDAI, mean (standard error) change in CDAI was -4.95 (0.24), -4.53 (0.27), and -2.52 (0.34) for 0-1, 2, and ≥ 3 PPF groups, respectively. More patients were working at baseline but not at 12-month followup in 2 (13.9%) and ≥ 3 (12.5%) versus 0-1 (7.3%) PPF group.

CONCLUSION

Despite high disease activity and worse clinical outcomes, number of PPF did not significantly predict biologic/tsDMARD use. This may warrant reconsideration of the importance of PPF in treat-to-target approaches.

Conversion to seronegative status after abatacept treatment in patients with early and poor prognostic rheumatoid arthritis is associated with better radiographic outcomes and sustained remission: post hoc analysis of the AGREE study

Objective

To evaluate the effects of the T-cell costimulation blocker abatacept on anti-citrullinated protein antibodies (ACPA) and rheumatoid factor (RF) in early rheumatoid arthritis (RA), and associations between changes in serological status and clinical response.

Methods

Post hoc analysis of the phase III AGREE study in methotrexate (MTX)-naïve patients with early RA and poor prognostic factors. Patients were randomised to abatacept (~10 mg/kg intravenously according to weight range) or placebo, plus MTX over 12 months followed by open-label abatacept plus MTX for 12 months. Autoantibody titres were determined by ELISA at baseline and months 6 and 12 (double-blind phase). Conversion to seronegative status and its association with clinical response were assessed at months 6 and 12.

Results

Abatacept plus MTX was associated with a greater decrease in ACPA (but not RF) titres and higher rates of both ACPA and RF conversion to seronegative status versus MTX alone. More patients converting to ACPA seronegative status receiving abatacept plus MTX achieved remission according to Disease Activity Score in 28 joints (C-reactive protein) or Clinical Disease Activity Index than patients who remained ACPA seropositive. Patients who converted to ACPA seronegative status treated with abatacept plus MTX had a greater probability of achieving sustained remission and less radiographic progression than MTX alone or patients who remained ACPA seropositive (either treatment).

Conclusions

Treatment with abatacept plus MTX was more likely to induce conversion to ACPA/RF seronegative status in patients with early, erosive RA. Conversion to ACPA seronegative status was associated with better clinical and radiographic outcomes.

Trial registration number

NCT00122382

Effect of Anticitrullinated Protein Antibody Status on Response to Abatacept or Antitumor Necrosis Factor-α Therapy in Patients with Rheumatoid Arthritis: A US National Observational Study

Objective.

Assess whether baseline anticyclic citrullinated peptide antibodies (anti-CCP) status is associated with treatment response in patients with rheumatoid arthritis (RA) initiating abatacept (ABA) or a tumor necrosis factor-α inhibitor (TNFi).

Methods.

Using the Corrona RA registry, patients were identified who initiated ABA or a TNFi (June 2004–January 2015), had a followup visit 6 months (± 3 mos) after initiation, and anti-CCP measured at or prior to initiation. Primary outcome was mean change in Clinical Disease Activity Index (CDAI) from initiation to 6 months. Treatment response was evaluated based on a typical patient profile (female, aged 57 yrs, body mass index of 30 kg/m2, baseline CDAI of 20, 1 prior biologic, and no comorbidities other than RA). Secondary outcomes included remission and low disease activity.

Results.

There were 566 ABA initiators [anti-CCP+ (≥ 20 units/ml): n = 362; anti-CCP− (< 20 units/ml): n = 204] and 1715 TNFi initiators (anti-CCP+: n = 1113; anti-CCP−: n = 602). Differences between treatment groups included baseline disease duration, CDAI, and prior biologic use. At 6 months, anti-CCP+ ABA initiators were associated with significantly greater CDAI response versus anti-CCP− ABA initiators; no significant difference was observed for TNFi initiators. When considering a typical RA patient profile, CDAI response was greater in anti-CCP+ versus anti-CCP− ABA initiators; anti-CCP+ versus anti-CCP− TNFi initiators were similar. Secondary outcome responses were also greater in anti-CCP+ versus anti-CCP− ABA initiators; TNFi initiators did not differ by anti-CCP status.

Conclusion.

In a US-based clinical practice setting, anti-CCP status was associated with a differential treatment response to ABA, but not TNFi.

Identification of biomarkers of response to abatacept in patients with SLE using deconvolution of whole blood transcriptomic data from a phase IIb clinical trial

Objective

To characterise patients with active SLE based on pretreatment gene expression-defined peripheral immune cell patterns and identify clusters enriched for potential responders to abatacept treatment.

Methods

This post hoc analysis used baseline peripheral whole blood transcriptomic data from patients in a phase IIb trial of intravenous abatacept (~10 mg/kg/month). Cell-specific genes were used with a published deconvolution algorithm to identify immune cell proportions in patient samples, and unsupervised consensus clustering was generated. Efficacy data were re-analysed.

Results

Patient data (n=144: abatacept: n=98; placebo: n=46) were grouped into four main clusters (C) by predominant characteristic cells: C1—neutrophils; C2—cytotoxic T cells, B-cell receptor-ligated B cells, monocytes, IgG memory B cells, activated T helper cells; C3—plasma cells, activated dendritic cells, activated natural killer cells, neutrophils; C4—activated dendritic cells, cytotoxic T cells. C3 had the highest baseline total British Isles Lupus Assessment Group (BILAG) scores, highest antidouble-stranded DNA autoantibody levels and shortest time to flare (TTF), plus trends in favour of response to abatacept over placebo: adjusted mean difference in BILAG score over 1 year, −4.78 (95% CI −12.49 to 2.92); median TTF, 56 vs 6 days; greater normalisation of complement component 3 and 4 levels. Differential improvements with abatacept were not seen in other clusters, except for median TTF in C1 (201 vs 109 days).

Conclusions

Immune cell clustering segmented disease severity and responsiveness to abatacept. Definition of immune response cell types may inform design and interpretation of SLE trials and treatment decisions.

Trial registration number

NCT00119678; results.

Brief Report: Estimating Disease Activity Using Multi-Biomarker Disease Activity Scores in Rheumatoid Arthritis Patients Treated With Abatacept or Adalimumab

Objective

To assess the ability of a multi‐biomarker disease activity (MBDA) test (Vectra DA) to reflect clinical measures of disease activity in patients enrolled in the AMPLE (Abatacept Versus Adalimumab Comparison in Biologic‐Naive RA Subjects with Background Methotrexate) trial.

Methods

In the AMPLE trial, patients with active rheumatoid arthritis (RA) who were naive to biologic agents and had an inadequate response to methotrexate were randomized (1:1) to receive subcutaneous abatacept (125 mg every week) or subcutaneous adalimumab (40 mg every 2 weeks), with background methotrexate, for 2 years. The MBDA score was determined using serum samples collected at baseline, month 3, and years 1 and 2. The adjusted mean change from baseline in the MBDA score was compared between the abatacept and adalimumab treatment groups. Cross‐tabulation was used to compare the MBDA score with the following clinical measures of disease activity: Clinical Disease Activity Index (CDAI), Simplified Disease Activity Index (SDAI), Disease Activity Score in 28 joints using the C‐reactive protein level (DAS28‐CRP), and Routine Assessment of Patient Index Data 3 (RAPID‐3).

Results

In total, 318 patients were randomized to receive abatacept, and 328 were randomized to receive adalimumab; MBDA data were available for 259 and 265 patients, respectively. No association between the MBDA score and disease activity defined by the CDAI, SDAI, DAS28‐CRP, or RAPID‐3 in the abatacept and adalimumab treatment groups was observed.

Conclusion

The MBDA score did not reflect clinical disease activity in patients enrolled in AMPLE and should not be used to guide decision‐making in the management of RA, particularly for patients who receive abatacept or adalimumab as the first biologic agent.

A window of opportunity for abatacept in RA: is disease duration an independent predictor of low disease activity/remission in clinical practice?

The objective of the study was to examine whether disease duration independently predicts treatment response among biologic-naïve patients with rheumatoid arthritis (RA) initiating abatacept in clinical practice. Using the Corrona RA registry (February 2006–January 2015), biologic-naïve patients with RA initiating abatacept with 12-month (±3 months) follow-up and assessment of disease activity (Clinical Disease Activity Index [CDAI]) at initiation and at 12 months were identified. The primary outcome was mean change in CDAI (ΔCDAI) from baseline to 12 months. Secondary outcomes at 12 months included achievement of low disease activity (LDA; CDAI ≤10 in patients with moderate/high disease activity at initiation) and remission (CDAI ≤2.8 in patients with low, moderate or high disease activity at initiation). Linear and logistic regression analyses were performed to examine the relationship between disease duration and response to abatacept. There were 281 biologic-naïve patients with RA initiating abatacept (disease duration 0–2 years, n = 107; 3–5 years, n = 45; 6–10 years, n = 50; >10 years, n = 79). Increased disease duration was associated with older age (p = 0.047), and the median number of prior conventional disease-modifying antirheumatic drugs used was lowest in the 0- to 2-year duration group (p < 0.001). Mean ΔCDAI (SE) ranged from −10.22 (1.19) for 0–2 years to −4.63 (1.38) for >10 years. In adjusted analyses, shorter disease duration was significantly associated with greater mean ΔCDAI (p = 0.015) and greater likelihood of achieving LDA (p = 0.048). In biologic-naïve patients with RA initiating abatacept, earlier disease (shorter disease duration) was associated with greater ΔCDAI and likelihood of achieving LDA.

Use of Digital Pupillometry to Measure Sedative Response to Propofol

BACKGROUND

Digital pupillometry (DP) accurately and precisely measures pupillary responses. Little is known about using DP to measure the sedative effect of isolated propofol administration.

METHODS

We conducted a cross-sectional study of 19 adults undergoing moderate sedation with propofol during which we measured pupillary changes using DP.

RESULTS

Maximum and minimum pupillary diameters decreased significantly with propofol (mean change from baseline to procedural termination -1.24 mm, standard error [SE] 0.25 and -0.79 mm, SE 0.13, respectively; P≤0.001 for both). Mean constriction velocity decreased by 0.84 mm/s between baseline and procedural termination (P=0.001). Pupillary latency increased significantly between baseline and induction (mean change 0.016 seconds, SE 0.007; P=0.04) but was not significantly different at other time points.

CONCLUSION

We speculate that DP may be a useful tool to monitor propofol sedation.

Impact of baseline anti-cyclic citrullinated peptide-2 antibody concentration on efficacy outcomes following treatment with subcutaneous abatacept or adalimumab: 2-year results from the AMPLE trial

Objectives

To examine whether baseline anti-cyclic citrullinated peptide-2 (CCP2) antibody status and concentration correlated with clinical outcomes in patients treated with abatacept or adalimumab on background methotrexate (MTX) in the 2-year AMPLE (Abatacept versus adaliMumab comParison in bioLogic-naïvE rheumatoid arthritis subjects with background MTX) study.

Methods

In this exploratory analysis, anti-CCP2 antibody concentration was measured at baseline, and antibody-positive patients were divided into equal quartiles, Q1–Q4, representing increasing antibody concentrations. Clinical outcomes analysed by baseline anti-CCP2 status and quartile included change from baseline in disease activity and disability and remission rates.

Results

Baseline characteristics were generally comparable across quartiles and treatment groups. In both treatment groups, anti-CCP2 antibody-negative patients responded less well than antibody-positive patients. At year 2, improvements in disease activity and disability and remission rates were similar across Q1–Q3, but were numerically higher in Q4 in the abatacept group; in contrast, treatment effects were similar across all quartiles in the adalimumab group.

Conclusions

In AMPLE, baseline anti-CCP2 positivity was associated with a better response for abatacept and adalimumab. Patients with the highest baseline anti-CCP2 antibody concentrations had better clinical response with abatacept than patients with lower concentrations, an association that was not observed with adalimumab.

Trial registration number

NCT00929864.

Improving Endoscopic Adherence to Quality Metrics in Colonoscopy

BACKGROUND

Appropriate documentation of quality metrics in the endoscopy reports provides evidence that a thorough and complete examination was performed. The aim of our study was to assess compliance with 3 current quality metrics for colonoscopy defined by the American Society for Gastrointestinal Endoscopy.

METHODS

We retrospectively examined colonoscopy reports from 6 gastroenterologists at Ochsner Medical Center for appropriate documentation of the quality of the bowel preparation and photodocumentation of the appendiceal orifice and the ileocecal valve. A performance review and educational session then took place with each physician. Subsequent colonoscopy reports were evaluated to monitor for improvement.

RESULTS

Bowel preparation documentation was high before and after the educational sessions (97.5% and 97.2%). Preeducation, the mean photodocumentation rate of the appendiceal orifice was 55% (range, 23%-84%). For the ileocecal valve, the documentation rate was 32.5% (range, 3%-73%). Posteducation, the mean appendiceal orifice labeling increased to an average of 91%, with a median change of 28.5% (P=0.0313). Documentation of the ileocecal valve improved to an average of 73%, a median change of 37.5% (P=0.0625).

CONCLUSION

Although reassessment of subsequent reports will be necessary to evaluate the permanence of this intervention, our evidence suggests that educational sessions can improve the quality and accuracy of documentation of quality metrics during colonoscopies.

Current status of chromoendoscopy and narrow band imaging in colonoscopy

Colonoscopy, the preferred procedure for colon cancer screening, has well-documented limitations. To improve colonoscopy's effectiveness, augmented endoscopy techniques, such as chromoendoscopy and narrow band imaging (NBI) have been evaluated. Both techniques are inexpensive, safe, and relatively easy to perform. Chromoendoscopy has an increasingly important role in surveillance of IBD, but significant work is needed to determine the optimal staining techniques and mucosal surface pattern analysis before this technique can be incorporated into routine clinical practice. NBI is a much newer technology with far less data. Well-designed prospective randomized controlled trials have failed to identify a benefit of NBI in screening colonoscopy, in surveillance for high-risk populations or as an adjunct for therapeutic procedures.

The versatile roles of antibodies in Borrelia infections

Antibodies are the primary weapons of the mammalian immune system that are used against the tick-borne borreliae, the causative agents of relapsing fever and Lyme disease worldwide. Some antibody responses have 'traditional' functions, whereas others are more versatile and have novel functions and modes of action. At a time when the multiple functions of antibodies are being increasingly recognized and passive immunization is being revived as therapy for infectious and other diseases, the versatile nature of the antibody response to the borreliae fits well with this antibody renaissance.

Generation of a complement-independent bactericidal IgM against a relapsing fever Borrelia

The spirochetemia of relapsing fever in mice is cleared by a complement-independent, polyclonal IgM response with reactivity to two prominent Ags of 20 and 35 kDa. In this study, we have dissected the polyclonal IgM Ab response against a relapsing fever spirochete to determine the specificity of its complement-independent bactericidal properties. Our experimental approach selectively generated an IgM murine mAb from the early specific immune response to a variable outer membrane protein. This IgM is bactericidal in the absence of complement and is part of the polyclonal Ab response that mediates the clearance of this bacterium from the blood. Purified monoclonal IgM caused direct structural damage to the outer membrane of the spirochete, in the absence of complement, and protected both B cell- and C5-deficient mice from challenge when administered passively. The direct, complement-independent, bactericidal activity of Abs is a critical mechanism of host defense against infection.

Cutting edge: the spirochetemia of murine relapsing fever is cleared by complement-independent bactericidal antibodies

Abs are the major effectors of host defense against infections with BORRELIA: Bactericidal murine mAbs and their Fabs destroy B. burgdorferi, the agent of Lyme disease, and relapsing fever Borrelia in the absence of complement. These in vitro observations led to the expansion of a search for functionally similar Abs in vivo. In this study, we demonstrate that functionally unique IgM Abs develop in vivo and are responsible for the elimination of spirochetemia in murine models of relapsing fever, without the assistance of complement. Mice deficient in the fifth or third component of complement can clear the spirochetemia, whereas B cell-deficient mice cannot. The B cell-deficient mice developed spirochetemia that was an order of magnitude higher and persisted for a longer period of time in comparison to the wild-type mice. Additionally, B cell-deficient mice passively immunized with immune IgM and with immune serum were protected from challenge.

Salvage of vision after hypotension-induced ischemic optic neuropathy

No effective treatment has been established for nonarteritic anterior ischemic optic neuropathy. Although most cases occur spontaneously, acute hypotension plays a clear role in a subset of patients. We examined three patients with severe visual loss from ischemic optic neuropathy induced by hypotension. The first patient developed anterior ischemic optic neuropathy after excessively rapid correction of malignant hypertension. In the second patient, anterior ischemic optic neuropathy occurred after an episode of orthostatic hypotension from systemic hypovolemia. The third patient developed anterior ischemic optic neuropathy after becoming hypotensive during a routine hemodialysis session. Measures were undertaken immediately to reverse the hypotension in all three patients. This intervention resulted in partial recovery of vision in each patient.

Labeled Schwann cell transplants versus sural nerve grafts in nerve repair

This study evaluated the ability of Schwann cell transplants to enhance the recovery of function in injured nerves and compared the results to those produced by sural nerve grafts. Schwann cells were isolated from sciatic nerves, prelabeled with gold fluorescent dye admixed with collagen gel, and placed in resorbable collagen tubes. Twenty-four adult rats underwent severing of the bilateral sciatic nerves, with a 10-mm gap between the nerve stumps. The rats were then divided into two groups. A collagen tube with implanted Schwann cells was implanted in one leg of the Group I rats, and the contralateral leg served as a control and was repaired with a collagen tube filled with collagen gel only. The Group II animals received conduits packed with labeled Schwann cells in one leg to bridge the 10-mm gap; the contralateral leg was repaired with an autogenous sural nerve graft. Recovery of function was assessed physiologically and morphologically. Nerve conduction velocity and nerve action potential amplitude measurements showed that the Schwann cell implants induced return of function comparable to that of the sural nerve grafts. Morphological assessments of myelination suggested a tendency toward greater numbers of myelinated axons in Schwann cell implants than in sural nerve grafts. Anatomical analyses of gold fluorescent dye showed both high viability of prelabeled Schwann cells at 120 days after transplantation and migration as far as 30 mm away from the implant site.

Comparison of macropore, semipermeable, and nonpermeable collagen conduits in nerve repair

Twelve rabbits were used to study functional nerve regeneration through macropore, semipermeable, and nonpermeable collagen conduits. Each animal underwent a 10-mm bilateral resection of posterior tibial nerve. Lesions were repaired with a macropore collagen tube in one leg, and with a semipermeable or a nonpermeable collagen tube contralaterally. Functional nerve regeneration was evaluated at 6 and 12 weeks post-repair periods. Functional recovery was assessed by electrophysiologic analysis of nerve conduction velocity, amplitude of nerve action potential, amplitude and area of muscle action potential, and by quantitative and qualitative histologic analysis of myelinated nerve fibers from the distal nerve stumps. The macropore-collagen-tube group showed significantly greater functional recoveries than semipermeable or nonpermeable collagen-tube groups, based on electrophysiologic and histologic analyses.

Immunohistochemical localization of basic fibroblast growth factor in mature and developing retinas of normal and RCS rats

Basic fibroblast growth factor (bFGF) delays photoreceptor degeneration when injected intraocularly in Royal College of Surgeons (RCS) rats with inherited retinal dystrophy. In the present study, we have determined the localization of endogenous bFGF in retinas of normal and RCS rats during the normal developmental period (postnatal days 0-20) and the period of photoreceptor degeneration in RCS rats (days 20-90). bFGF was localized immunohistochemically by indirect immunoperoxidase using two different polyclonal antibodies and one monoclonal antibody against bFGF. bFGF was present in retinas as early as birth, and remained through adult age. Controls using either PBS, non-immune IgG or antibody preabsorbed with bFGF peptide were devoid of label. In normal rats between the ages of birth and postnatal day (P) 4, bFGF was found in developing ganglion cells, superficial blood vessels, some of the innermost cells in the neuroblastic layer, developing horizontal cells, and retinal pigment epithelial (RPE) cells. Between P0 and P4, the intensity of staining increased significantly in horizontal cells. From P6-P10, some cells in the inner nuclear layer remained positive, but horizontal cell staining became less intense in the central retina. The superficial vessels, ganglion cells and RPE cells also remained positive for bFGF. At P20-25, when the retina was essentially mature, bFGF was found in RPE cells, most cells of the ganglion cell layer, and many cells of the inner nuclear layer, but horizontal cells and blood vessels showed a lower concentration of bFGF than they did at younger ages. At P45 and older, blood vessels no longer showed bFGF immunoreactivity. The staining pattern in RCS rats was indistinguishable from that for normal rats at all ages examined. These results show that bFGF is present in the developing and adult rat retina in some neural cells, in addition to vessels and RPE cells. The transient elevated expression of bFGF immunoreactivity in developing horizontal cells and blood vessels suggests a possible role for this growth factor in retinal development. In addition, if RCS retinas possess any difference in bFGF localization or concentration compared to normal retinas, it must be too small to detect by immunohistochemical means, or at least with the reagents used.

Electrophysiological studies of various graft lengths and lesion lengths in repair of nerve gaps in primates

Electrophysiological studies were used to evaluate neurological recovery in 14 rhesus monkeys with different nerve lesion lengths and graft lengths. After exposure of both sciatic nerves in each animal, baseline evoked nerve action potentials, muscle action potentials, and muscle strength values were determined for the posterior tibial nerves. Each nerve was then crushed over a measured distance. Three weeks later, the crushed segments were resected and the defects repaired with sural nerve grafts. In seven animals, 20-mm resection sites were repaired by 4 x 20-mm grafts in one leg and by 4 x 40-mm grafts contralaterally. In the other seven animals, the lengths of resection sites were 10 mm in one leg and 30 mm contralaterally; both nerve defects in these animals were repaired by 4 x 30-mm grafts. Electrophysiological studies were repeated at one interval of either 4, 7, or 12 months after repair. Postoperative electrophysiological values were compared to baseline values and described by the mean values and by percent recovery. Muscle strength recovery was significantly better in limbs with short lesions. In animals with identical lesion lengths, lesions repaired with shorter grafts (the same length as the defect) did significantly worse than did lesions repaired with longer grafts. This may suggest that any degree of tension at the graft repair site has a deleterious effect on functional nerve regeneration. Nevertheless, it was generally found that nerve lesion length had the greatest negative effect on functional nerve regeneration.

Initial evaluation of variable graft lengths and lesion lengths in the repair of nerve gaps

This experiment evaluated the electrical and histologic differences between two groups of rats, one of which underwent same-length bilateral resection of posterior tibial nerves prior to being repaired with grafts of different lengths, while the other group underwent different-length resections with same-length graft repair. In this rat model, 18 animals were used and divided into two groups. The first group of animals underwent bilateral resection of 8-mm segments of posterior tibial nerve. To repair these nerves, one leg received two 8-mm sural nerve grafts (Group A), while the other leg received two 16-mm sural nerve grafts (Group B). The second group of rats underwent posterior tibial nerve resections of 8 mm and 16 mm, respectively. The leg with the 8 mm of posterior tibial nerve resected, received two side-by-side 16-mm sural nerve grafts (Group C); the other leg with 16 mm resected, received two 16-mm sural nerve grafts (Group D). Electrophysiologic comparison of nerve conduction velocity for Groups A and B showed a significant difference (p less than 0.05), as did the same comparison for Groups C and D (p less than 0.05). Histologic studies showed that Groups A and D had marked extrafascicular escape of the regenerating nerve axons, disorganizational growth of minifascicles, and loss of integrity of the donor fascicles, while Groups B and C had very minimal extrafascicular escape of regenerating axons.(ABSTRACT TRUNCATED AT 250 WORDS)

A prototype retractor system designed to minimize ischemic brain retractor injury: initial observations

The authors have developed and patented a neurosurgical retractor system incorporating an infrared emitter and detector that allows detection of cerebral pulsations. Gentle contact with the surface of cat brains shows cerebral pulsations that correlate with arterial pulse as well as mechanical ventilation. The amplitude of cerebral pulsations decreases with higher retraction pressure and disappears at approximately 20 mmHg. The pressure on the surface of the brain decreased 50% in 5 minutes even though the position of the retractor was maintained constant. The authors postulate that monitoring cerebral pulsation may prove useful in clinical neurosurgery with respect to avoiding excessive retraction, which causes brain damage.

Characterization of vascular development in the mouse retina

The murine retina provides an ideal model for the study of vascular development. In this investigation we have examined the development of blood vessels in flat-mounted whole retinas from C57B6 mice ranging from birth to 4 months of age. Basement membrane components of blood vessels were visualized by indirect immunofluorescence with antibodies against type IV collagen and laminin. Endothelial cells (EC) were labeled with a plant lectin, Ricinus communis agglutinin I (RCA), and antibodies against angiotensin converting enzyme. Results show three stages of vascular differentiation. During the first stage (postnatal days P0-P10), vessels develop radially from optic disc to ora serrata within the presumptive nerve fiber layer. In the second stage beginning P4, vessels form within deeper retinal layers. In the third stage beginning P7, a capillary network develops as branches of radial vessels in the nerve fiber layer. The entire vascular system begins as a polygonal network of capillary-like vessels. Selective regression of various segments of these polygons leads to the ultimate arborous pattern of arteries, arterioles, veins, venules, and capillaries seen in the adult. Some individual EC appear to be left behind during this retraction process and pericytes may have a role in determining which vessel segments regress. This combination of flat-mounted whole retinas and probes specific for vascular elements provides an ideal system for the study of retinal vascularization and the characterization of vasculogenesis in general.