Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

O-077 The chromosomal constitution of embryos developing from 0PN zygotes

Study question

To compare the ploidy status of embryos originated from zygotes with absence of pronuclei (0PN) with those developing from normal two pronuclei (2PN) fertilization.

Summary answer

We did not find significant differences in euploidy rates between blastocysts from 0PN and 2PN zygotes.

What is known already

Information regarding the ploidy number of 0PN zygotes, even when the pronuclei number is assessed by time-lapse microscope coupled incubators, is still insufficient. Because of this, embryos originating from 0PN zygotes are usually discarded or individualized in order not to include them in first transfers. Even more, abnormal fertilization is considered as a proxy of poor embryo quality.

Study design, size, duration

A retrospective observational study from March 2016 and December 2021 including 80 PGT-A cycles in which at least one of the blastocysts studied developed from oocytes in which pronuclei were not seen at the time of fertilization check.

Participants/materials, setting, methods

307 blastocysts were studied, of which 115 originated from 0PN and 192 from 2PN zygotes. Pronuclear number was assessed 16-20 h after insemination. Zygotes with 0PN were cultured separately from 2PN ones of the same cohort. After extended culture, a biopsy was performed and the material obtained was genetically studied using Next Generation Sequencing. Statistical comparisons were made with Fisher's exact and Chi-square tests. Significance level was set at P<0.05.

Main results and the role of chance

No differences were observed in euploidy rates between the 2PN and 0PN groups [55.2% (106/193) VS 43.5% (50/115)]. In aneuploid embryos originating from 2PN zygotes, a similar amount of trisomies and monosomies was observed (56 and 56 respectively). In contrast, aneuploid embryos from 0PN oocytes showed a greater number of trisomies than monosomies (55 and 35 respectively, P < 0.05). None of the blastocysts resulting from 0PN was haploid, that is, we did not find parthenogenic embryos. Blastocysts derived from 0PN zygotes showed similar quality scoring than those from 2PN ones. To date, 20 euploid blastocysts from the 0PN group have been transferred, producing 12 pregnancies: 6 still ongoing and 4 healthy live births.

Limitations, reasons for caution

Non-visualization of pronuclei in oocytes that later generate normal diploid blastocysts may be due to a faster or slower cell cycle progression. Modifications in the daily fertilization check schedules of busy laboratories should also be considered.

Wider implications of the findings

Contrary to expectations, aneuploid embryos from 0PN oocytes showed a greater number of trisomies than monosomies. A significant fraction of the embryos generated from 0PN zygotes were actually diploid, with similar quality and outcome results than 2PN ones. This makes them perfectly usable in IVF routines.

Trial registration number

Not applicable

P-223 Women aged 40 or older and non-male factor have the same reproductive outcome using intracytoplasmic sperm injection (ICSI) or conventional in vitro fertilization (cIVF)

Study question

Do women aged 40 or older have the same reproductive outcome using ICSI or cIVF when male factor infertility is not present?

Summary answer

Women aged 40 or older with non-male factor partners achieved similar reproductive outcomes either with ICSI or cIVF.

What is known already

Although initially proposed to treat couples with severe male factor infertility, ICSI has become the preferred tool to treat patient populations others than initially intended. Many studies and international forums, however, have alerted that its overuse is not free due to its safety, cost and time-consuming concerns. Moreover, it was noted that it does not increase clinical outcomes even in cases of compromised oocyte factor such as poor responder patients or few oocytes retrieved. However, there is still no information regarding its use in the group of patients of advanced reproductive age.

Study design, size, duration

Retrospective cohort study including 412 women aged 40 or older with non-male factor infertility performing ICSI or cIVF between May 2015 and October 2017.

Participants/materials, setting, methods

Patients underwent ICSI (n = 109) or cIVF (n = 303) according to medical indication. The decision to use ICSI in non-male factor patients was merely operational, with the objective of evaluating oocyte maturity.Those cycles with own oocytes, non-male factor and fresh embryo transfers were included. Semen samples were considered normal following the World Health Organization fifth edition sperm parameters values, and prepared by density gradient selection.

Main results and the role of chance

The primary outcome was clinical pregnancy rate. Secondary outcomes included ongoing pregnancy, miscarriage and implantation rates. Statistical significance was denoted by P < 0.05. The mean age of the women were 41.4 in the ICSI group and 41.6 years in the cIVF group, while the mean age for male couple was 43.6 and 41.6 respectively.

No differences between ICSI and cIVF groups were observed regarding clinical pregnancy [16.5% (18/109) vs. 20.8% (63/303)], ongoing pregnancy [9.2% (10/109) vs. 7.9% (24/303)], miscarriage [41.2% (7/17) vs. 46,5% (20/43)], and implantation rates [11.3% (17/151) vs. 9.9% (50/506)].

Limitations, reasons for caution

These results need confirmation with a bigger population size. As with any retrospective study, the potential for residual confounding exists.

Wider implications of the findings

These data suggest that ICSI offers no clinical benefit for women aged 40 and older with non-male factor infertility, beyond oocyte maturation classification.

Trial registration number

not applicable

POS0454 COMPARISON OF MBDA SCORE, PATIENT GLOBAL ASSESSMENT AND EVALUATOR GLOBAL ASSESSMENT FOR PREDICTING RISK OF RADIOGRAPHIC PROGRESSION

Background:

Busy rheumatologists may assess disease activity and risk for radiographic progression (RP) in RA with informal, qualitative versions of evaluator and/or patient global assessments (EGA and PGA). RA patient care may be improved by having a convenient, objective disease activity measure that predicts risk for RP more accurately than EGA or PGA.

Objectives:

To compare the abilities of MBDA score, patient global assessment and evaluator global assessment to assess risk for radiographic progression (RP), and to assess the ability of MBDA score to predict RP among patients with concordant or discordant PGA and EGA.

Methods:

Patients were pooled from two RCTs of patients with recent onset RA treated with conventional and biologic DMARDs (OPERA and SWEFOT, N=386) and from a registry of patients with predominantly established RA and diverse treatments (BRASS, N=380). Pearson correlations were determined between MBDA scores (adjusted for the effects of age, sex and adiposity) (scale 1-100), PGA and EGA (each on a scale of 1-10) at baseline. PGA and EGA were considered discordant when they differed by >2.5. Univariable logistic regression assessed ability to predict RP (change in TSS >5 over 1 year) for MBDA score, PGA and EGA as continuous variables; and for discordance of PGA and EGA as 2-level (concordant vs. discordant) or 3-level (PGA>EGA, concordant, EGA>PGA) categorical variables. Multivariable regression considered the main effect and interaction terms of the MBDA score, as a continuous variable, paired with each other variable, to test the ability of each pair to assess risk of RP. All models included a random effect on cohort. Odds ratios were reported for every 10-unit increase in MBDA score. Frequency of RP was determined in subgroups with MBDA score low (<30), moderate (30-44) or high (>44) for patient groups based on PGA/EGA concordance or discordance.

Results:

The 766 patients studied were 76% female, 76% positive for RF and/or anti-CCP Ab, with mean age 55 years, DAS28-CRP 4.7, CRP 22 mg/L, CDAI 26, SJC 9.1, PGA 4.4, EGA 3.4, MBDA score 53. No interaction was seen between MBDA score and type of cohort (early vs established RA). PGA and EGA were discordant in 294 of 766 (38%) patients and were weakly to moderately correlated (r=0.38). Among discordant patients, PGA was >EGA in 227 cases and EGA was >PGA in 67 cases. Correlations between MBDA score and PGA or EGA were r=0.41 and r=0.34, respectively. In univariable analyses, MBDA score was a statistically significant predictor of radiographic progression (OR=1.53, p=6.3x10-8) whereas PGA, EGA, 2-level discordance and 3-level discordance were not (p=0.38, 0.47, 0.74, 0.83, respectively). In multivariable analyses, significant interactions were observed between MBDA score and discordance (2-level, p=0.0029; 3-level, p=0.0087). The interaction analysis demonstrated, in PGA/EGA-concordant patients, low risk of radiographic progression when MBDA score was low and elevated risk when it was high (OR=1.33 [1.1, 1.59]). A relationship between MBDA score and RP risk was also demonstrated, with heightened trend, among discordant patients with PGA >EGA (OR=2.04 [1.53, 2.81]) and EGA >PGA (OR=3.43 [1.37, 13.8]) (Figure 1).

Conclusion:

MBDA score was a significant predictor of radiographic progression, whereas PGA and EGA were not. MBDA score predicted progression whether PGA and EGA were concordant or discordant. These results suggest that MBDA score detects joint-damaging disease activity more accurately than PGA and EGA and it does so whether or not PGA and EGA are in agreement.

Disclosure of Interests:

Leonard Calabrese Grant/research support from: AbbVie, Bristol-Myers Squibb, Cresecendo, Genentech, Gilead, GlaxoSmithKline, Horizon, Janssen, Novartis, and Sanofi., Michael E. Weinblatt Shareholder of: Canfite, Inmedix, Scipher, and Vorso, Consultant of: AbbVie, Aclaris, Amgen, Bayer, Bristol-Myers Squibb, Crescendo Bioscience, Corrona, EqRX, GSK,Genosco, Gilead, Lilly, Novartis, Pfizer, Roche, Set Point, Grant/research support from: Bristol-Myers Squibb, Myriad Genetics, Inc.,Eli Lilly and Sanofi, Nancy Shadick Consultant of: BMS, Grant/research support from: Lilly, mallinckrodt, BMS, Amgen and Sanofi, Cecilie Heegaard Brahe: None declared, Mikkel Østergaard Consultant of: Abbvie, BMS, Boehringer-Ingelheim, Celgene, Eli-Lilly, Centocor, GSK, Hospira, Janssen, Merck, Novartis, Orion, Pfizer, Regeneron, Roche, Takeda, and UCB, Grant/research support from: AbbVie, BMS, Celgene, Myriad Genetics, Inc., Janssen, and Merck, Merete L. Hetland Speakers bureau: Orion, Grant/research support from: AbbVie, Biogen, BMS, CelltrionRoche, Myriad Genetics, Inc., Eli Lily, MSD, Pfizer, and UCB, Megan Horton Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Darl Flake Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Eric Sasso Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Autoimmune

AB1243 TRAINING AND VALIDATION OF A MULTIVARIATE PREDICTOR OF RISK OF RADIOGRAPHIC PROGRESSION FOR PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

The multi-biomarker disease activity (MBDA) score, adjusted for age, sex and adiposity (MBDAadj), has been shown to be better than several conventional disease activity measures for predicting risk for radiographic progression (RP) in patients with rheumatoid arthritis (RA).1Serologic status and other non-disease activity measures are also predictive of RP risk. Combining them with the MBDAadjshould result in a stronger prognostic test for RP than any one measure alone.

Objectives:

Develop a multivariate model for predicting risk for RP that includes the adjusted MBDA score and other known predictors of RP.

Methods:

Four RA cohorts were used, two for training (OPERA and BRASS, n=555) and two for validation (SWEFOT and Leiden, n=397). Each pair of cohorts was heterogeneous in disease duration and treatment history. BMI data were not available for one validation cohort, so a BMI surrogate was modeled using forward selection with the two training cohorts and 3 others (CERTAIN, InFoRM, RACER) (N=1411). An RP risk score was then trained using forward selection in a linear mixed-effects regression, considering disease-related and demographic variables as predictors of change in modified total Sharp score over one year (ΔmTSS), with a random effect on cohort. The RP risk score was validated as a predictor of RP with two cutoffs (ΔmTSS >3 and >5) using logistic mixed-effects regression. Odds ratios (OR) and 95% profile likelihood-based confidence intervals (CI) were calculated from the models and significance was assessed by likelihood ratio tests. Risk curves were generated to show probability of RP as a function of the RP risk score.

Results:

The BMI surrogate included leptin, sex, age and age2and correlated well with BMI (ρ = 0.76). In training, the most significant independent predictors of RP were MBDAadj(p = 0.00020), seropositivity (p = 9.3 x 10-5), BMI surrogate score (p = 0.013) and use of targeted therapy (p = 0.0026). The final model was: RP risk score = 0.024 x MBDAadj+ 0.093 if seropositive – 0.063 x BMI surrogate score – 0.61 if using a targeted therapy. In validation, the OR (95% CI) of the RP risk score for predicting ΔTSS >3 or >5 were 2.2 (1.6, 3.2) (p = 2.6 × 10-6) and 3.1 (2.0, 5.0) (p = 5.7 × 10-8), respectively (Figure 1). The odds of a patient having RP increases by 50% for each 21-unit or 15-unit increase in MBDAadj, for RP defined as ΔTSS >3 or >5, respectively.

Figure 1.

Conclusion:

A multivariate model containing adjusted MBDA score, seropositivity, a BMI surrogate and use of targeted therapy has been trained and validated as a prognostic test for radiographic progression in RA.

References:

[1]Curtis, et al.Rheumatology [Oxford].2018;58:874

Disclosure of Interests:

Thomas Huizinga Grant/research support from: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Consultant of: Ablynx, Bristol-Myers Squibb, Roche, Sanofi, Michael E. Weinblatt Grant/research support from: BMS, Amgen, Lilly, Crescendo and Sonofi-Regeneron, Consultant of: Horizon Therapeutics, Bristol-Myers Squibb, Amgen, Abbvie, Crescendo, Lilly, Pfizer, Roche, Gilead, Nancy Shadick Grant/research support from: Mallinckrodt, BMS, Lilly, Amgen, Crescendo Biosciences, and Sanofi-Regeneron, Consultant of: BMS, Cecilie Heegaard Brahe: None declared, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Merete L. Hetland Grant/research support from: BMS, MSD, AbbVie, Roche, Novartis, Biogen and Pfizer, Consultant of: Eli Lilly, Speakers bureau: Orion Pharma, Biogen, Pfizer, CellTrion, Merck and Samsung Bioepis, Saedis Saevarsdottir Employee of: Part-time at deCODE Genetics/Amgen Inc, working on genetic research unrelated to this project, Megan Horton Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Brent Mabey Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Darl Flake Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Rotem Ben-Shachar Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Eric Sasso Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Alexander Gutin Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Elena Hitraya Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Jerry Lanchbury Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Jeffrey Curtis Grant/research support from: AbbVie, Amgen, Bristol-Myers Squibb, Corrona, Janssen, Lilly, Myriad, Pfizer, Regeneron, Roche, UCB, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Corrona, Janssen, Lilly, Myriad, Pfizer, Regeneron, Roche, UCB

AB1239 THE EFFECT OF INFLUENZA VACCINATION ON THE MULTI-BIOMARKER DISEASE ACTIVITY SCORE AND ITS COMPONENT BIOMARKERS IN HEALTHY SUBJECTS

Background:

The multi-biomarker disease activity (MBDA) blood test measures 12 protein biomarkers (IL-6, CRP, SAA, EGF, VEGF, VCAM, MMP-1, MMP-3, leptin, resistin, TNF-RI and YKL40). It uses a validated algorithm to provide a score on a scale of 1-100 for assessing disease activity in patients with rheumatoid arthritis (RA). The MBDA score reflects several molecular aspects of inflammation, including cytokines, acute phase reactants, growth factors, molecular adhesion, metalloproteinases and hormones. Insights gained by understanding how vaccination affects these biomarkers in healthy subjects - in whom the level of inflammation prior to vaccination should be low and stable - may aid the understanding of how vaccination affects patients with RA.

Objectives:

The goal of this study was to understand how immunization of healthy subjects with the influenza vaccine affects the assessment of inflammation with the MBDA score and its 12 biomarkers.

Methods:

A 4-strain influenza virus vaccine (Fluarix Quadrivalent, GlaxoSmithKline) was administered intramuscularly to 22 healthy volunteer subjects on October 24, 2018. Serum samples were obtained immediately prior to vaccination (baseline) and 1, 2 and 3 weeks after vaccination. No restrictions were placed on subject activity. Samples were stored at -80oC until measurement of the 12 MBDA biomarkers for determination of the adjusted MBDA score, hereafter called the MBDA score. (Adjustment accounts for the effects of age, sex and adiposity1). MBDA scores (natural scale) and biomarker concentrations (log scale) were modeled using generalized estimating equations (GEE) that account for correlations between measurements from the same subject at multiple timepoints. Significance of MBDA score change or biomarker concentration change over time was determined by a likelihood ratio test of timepoints.

Results:

Of the 22 healthy subjects receiving the influenza virus vaccine, 14 (63.6%) were female, with mean (SD) age of 40.0 years (8.9). MBDA scores were low (<30), moderate (30-44) or high (>44) for 15 (68%), 6 (27%) and 1 (5%) subjects at baseline, and this distribution was stable over time (Figure 1). Overall, MBDA scores did not change significantly over time (p=0.48, Figure 2). Mean changes in MBDA score (95% CI) from baseline to weeks 1, 2 and 3 were 0.32 (-3.07, 3.71), 0.82 (-3.03, 4.67) and 2.86 (-1.10, 6.82), respectively (Figure 2); the week 3 value becomes 0.95 (-1.78, 3.68) if the week 3 outlier is removed. Among the 66 post-baseline measurements of change in MBDA score (Figure 2), 3 (5%) exceeded the 95% CI for change in MBDA score in this study (i.e., 14). When assessing the entire cohort across all timepoints, EGF was the only biomarker that demonstrated statistically significant change over time (p=5.6 x 10-7). At weeks 1, 2 and 3, the mean relative concentrations of EGF, compared with baseline, were 0.62 (0.52, 0.74), 0.86 (0.70, 1.06) and 0.62 (0.50, 0.76), respectively.

Figure 1Figure 2

Conclusion:

Immunization of 22 healthy subjects with a quadrivalent influenza vaccine did not have a statistically significant effect on MBDA scores during a 3-week observation, and it had minimal effect on the component biomarkers.

References:

[1]Curtis et al.Rheumatology [Oxford]2018;58:874

Disclosure of Interests:

Daniel Furst Grant/research support from: AbbVie, Actelion, Amgen, BMS, Corbus Pharmaceuticals, the National Institutes of Health, Novartis, Pfizer, and Roche/Genentech, Consultant of: AbbVie, Actelion, Amgen, BMS, Cytori Therapeutics, Corbus Pharmaceuticals, the National Institutes of Health, Novartis, Pfizer, and Roche/Genentech, Speakers bureau: CMC Connect (McCann Health Company), Lauren Lenz Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Megan Horton Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Darl Flake Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Eric Sasso Shareholder of: Myriad Genetics, Inc., Employee of: Myriad Genetics, Inc., Michael E. Weinblatt Grant/research support from: BMS, Amgen, Lilly, Crescendo and Sonofi-Regeneron, Consultant of: Horizon Therapeutics, Bristol-Myers Squibb, Amgen, Abbvie, Crescendo, Lilly, Pfizer, Roche, Gilead

Development of a parent-reported questionnaire evaluating upper limb activity limitation in children with cerebral palsy

BACKGROUND AND PURPOSE

Upper limb activity measures for children with cerebral palsy have a number of limitations, for example, lack of validity and poor responsiveness. To overcome these limitations, we developed the Children's Arm Rehabilitation Measure (ChARM), a parent-reported questionnaire validated for children with cerebral palsy aged 5-16 years. This paper describes both the development of the ChARM items and response categories and its psychometric testing and further refinement using the Rasch measurement model.

METHODS

To generate valid items for the ChARM, we collected goals of therapy specifically developed by therapists, children with cerebral palsy, and their parents for improving activity limitation of the upper limb. The activities, which were the focus of these goals, formed the basis for the items. Therapists typically break an activity into natural stages for the purpose of improving activity performance, and these natural orders of achievement formed each item's response options. Items underwent face validity testing with health care professionals, parents of children with cerebral palsy, academics, and lay persons. A Rasch analysis was performed on ChARM questionnaires completed by the parents of 170 children with cerebral palsy from 12 hospital paediatric services. The ChARM was amended, and the procedure repeated on 148 ChARMs (from children's mean age: 10 years and 1 month; range: 4 years and 8 months to 16 years and 11 months; 85 males; Manual Ability Classification System Levels I = 9, II = 26, III = 48, IV = 45, and V = 18).

RESULTS

The final 19-item unidimensional questionnaire displayed fit to the Rasch model (chi-square p = .18), excellent reliability (person separation index = 0.95, α = 0.95), and no floor or ceiling effects. Items showed no response bias for gender, distribution of impairment, age, or learning disability.

DISCUSSION

The ChARM is a psychometrically sound measure of upper limb activity validated for children with cerebral palsy aged 5-16 years. The ChARM is freely available for use to clinicians and nonprofit organisations.

Imaging and Baseline Predictors of Cognitive Performance in Minor Ischemic Stroke and Patients With Transient Ischemic Attack at 90 Days

Background and Purpose—

Few studies have examined predictors of cognitive impairment after minor ischemic stroke and transient ischemic attack (TIA). We examined clinical and imaging features associated with worse cognitive performance at 90 days.

Methods—

TIA or patients with minor stroke underwent neuropsychological testing 90 days post event. Z scores were calculated for cognitive tests, and then grouped into domains of executive function (EF), psychomotor processing speed (PS), and memory. White matter hyperintensity and diffusion-weighted imaging volumes were measured on baseline magnetic resonance imaging. Ninety-day outcomes included modified Rankin Scale (mRS) and Centre for Epidemiological Studies Depression Scale (CES-D) score.

Results—

Ninety-two patients were included, 76% male, 54% TIA, and mean age 65.1±12.0. Sixty-four percent were diffusion-weighted imaging positive. Median domain z scores were not significantly different from published norms ( P >0.05): memory −0.03, EF −0.12, and PS −0.05. Patient performance ≥1 SD below normal was 20% on memory, 16% on PS, and 17% on EF. Cognitive scores did not differ by diagnosis (stroke versus TIA), stroke pathogenesis, presence of obstructive sleep apnea, and diffusion-weighted imaging or white matter hyperintensity volumes. In multivariable analyses, lower EF was associated with previous cortical infarct on magnetic resonance imaging ( P =0.03), mRS score of >1; P =0.0003 and depressive symptoms (CES-D ≥16; P =0.03). Lower PS scores were associated with previous cortical infarct ( P =0.02), acute bilateral positive diffusion-weighted imaging ( P =0.02), mRS score of >1 ( P =0.003), and CES-D ≥16 ( P =0.03).

Conclusions—

Despite average-range cognitive performance in this TIA and population with minor stroke, we found associations of EF and PS with evidence of previous stroke, postevent disability, and depression.

Canadian Stroke Best Practice Recommendations: Hyperacute Stroke Care Guidelines, Update 2015

The 2015 update of the Canadian Stroke Best Practice Recommendations Hyperacute Stroke Care guideline highlights key elements involved in the initial assessment, stabilization, and treatment of patients with transient ischemic attack (TIA), ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, and acute venous sinus thrombosis. The most notable change in this 5th edition is the addition of new recommendations for the use of endovascular therapy for patients with acute ischemic stroke and proximal intracranial arterial occlusion. This includes an overview of the infrastructure and resources required for stroke centers that will provide endovascular therapy as well as regional structures needed to ensure that all patients with acute ischemic stroke that are eligible for endovascular therapy will be able to access this newly approved therapy; recommendations for hyperacute brain and enhanced vascular imaging using computed tomography angiography and computed tomography perfusion; patient selection criteria based on the five trials of endovascular therapy published in early 2015, and performance metric targets for important time-points involved in endovascular therapy, including computed tomography-to-groin puncture and computed tomography-to-reperfusion times. Other updates in this guideline include recommendations for improved time efficiencies for all aspects of hyperacute stroke care with a movement toward a new median target door-to-needle time of 30 min, with the 90th percentile being 60 min. A stronger emphasis is placed on increasing public awareness of stroke with the recent launch of the Heart and Stroke Foundation of Canada FAST signs of stroke campaign; reinforcing the public need to seek immediate medical attention by calling 911; further engagement of paramedics in the prehospital phase with prehospital notification to the receiving emergency department, as well as the stroke team, including neuroradiology; updates to the triage and same-day assessment of patients with transient ischemic attack; updates to blood pressure recommendations for the hyperacute phase of care for ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. The goal of these recommendations and supporting materials is to improve efficiencies and minimize the absolute time lapse between stroke symptom onset and reperfusion therapy, which in turn leads to better outcomes and potentially shorter recovery times.

Neuropeptide Y receptor Y5 as an inducible pro-survival factor in neuroblastoma: implications for tumor chemoresistance

Neuroblastoma (NB) is a pediatric tumor of neural crest origin with heterogeneous phenotypes. While low stage tumors carry a favorable prognosis, over 50% of high risk NB relapses after treatment with a fatal outcome. Thus, developing therapies targeting refractory NB remains an unsolved clinical problem. Brain-derived neurotrophic factor (BDNF) and its TrkB receptor are known to protect NB cells from chemotherapy-induced cell death, while neuropeptide Y (NPY), acting via its Y2 receptor (Y2R), is an autocrine proliferative and angiogenic factor crucial for maintaining NB tumor growth. Here, we show that in NB cells, BDNF stimulates the synthesis of NPY and induces expression of another one of its receptors, Y5R. In human NB tissues, the expression of NPY and Y5R positively correlated with the expression of BDNF and TrkB. Functionally, BDNF triggered Y5R internalization in NB cells, while Y5R antagonist inhibited BDNF-induced p44/42-MAPK activation and its pro-survival activity. These observations suggested TrkB-Y5R transactivation that resulted in cross-talk between their signaling pathways. Additionally, NPY and Y5R were up-regulated in a BDNF-independent manner in NB cells under pro-apoptotic conditions, such as serum deprivation and chemotherapy, as well as in cell lines and tissues derived from post-treatment NB tumors. Blocking Y5R in chemoresistant NB cells rich in this receptor sensitized them to chemotherapy-induced apoptosis and inhibited their growth in vivo by augmenting cell death. In summary, the NPY/Y5R axis is an inducible survival pathway activated in NB by BDNF or cellular stress. Upon such activation, Y5R augments the pro-survival effect of BDNF via its interactions with TrkB receptor and exerts an additional BDNF-independent anti-apoptotic effect, both of which contribute to NB chemoresistance. Therefore, the NPY/Y5R pathway may become a novel therapeutic target for patients with refractory NB, thus far an incurable form of this disease.

Refinement of Imaging Predictors of Recurrent Events following Transient Ischemic Attack and Minor Stroke

Background

TIA and minor stroke have a high risk of recurrent stroke. Abnormalities on CT/CTA and MRI predict recurrent events in TIA and minor stroke. However there are many other imaging abnormalities that could potentially predict outcome that have not been assessed in this population. Also the definition of recurrent events used includes deterioration due to stroke progression or recurrent stroke and whether imaging is either of these is not known.

Aims

To improve upon the clinical, CT/CTA and MRI parameters that predict recurrent events after TIA and minor stroke by assessing further imaging parameters. Secondary aim was to explore predictors of stroke progression versus recurrent stroke.

Methods

510 consecutive TIA and minor stroke patients had CT/CTA and most had MRI. Primary outcome was recurrent events (stroke progression or recurrent stroke) within 90 days. Further imaging parameters were assessed for prediction of recurrent events (combined outcome of stroke progression and recurrent stroke). We also explored predictors of symptom progression versus recurrence individually.

Results

36 recurrent events (36/510, 7.1% (95% CI: 5.0–9.6)) including 19 progression and 17 recurrent strokes. On CT/CTA: white matter disease, prior stroke, aortic arch focal plaque≥4 mm, or intraluminal thrombus did not predict recurrent events (progression or recurrent stroke). On MRI: white matter disease, prior stroke, and microbleeds did not predict recurrent events. Parameters predicting the individual outcome of symptom progression included: ongoing symptoms at initial assessment, symptom fluctuation, intracranial occlusion, intracranial occlusion or stenosis, and the CT/CTA metric. No parameter was strongly predictive of a distinct recurrent stroke.

Conclusions

There was no imaging parameter that could improve upon our original CT/CTA or MRI metrics to predict the combined outcome of stroke progression or a recurrent stroke after TIA and minor stroke. We are better at using imaging to predict stroke progression rather than recurrent stroke.

Abstract WP56: Refinement of imaging predictors of recurrent events following Transient Ischemic Attack and Minor Stroke

Background: Transient ischemic attack (TIA) and minor stroke have a high risk of recurrent stroke. We recently showed in the CATCH study that predefined radiographic abnormalities on CT/CTA and MRI predicted recurrent events after TIA and minor stroke. Specifically, the study recognized the predictive value of CT/CTA abnormalities that were defined apriori: acute ischemia on CT, intracranial or extracranial occlusion or stenosis > 50% (the CT/CTA positive metric), and diffusion-weighted imaging positivity on MRI.

Aims: To improve upon the CT, CTA, MRI and clinical parameters that predict recurrent events after TIA and minor stroke. Our secondary aim was to explore predictors of stroke progression versus recurrence.

Methods: 510 consecutive TIA and minor stroke patients (NIHSS score of <4) had CT/CTA and most had MRI. Primary outcome was recurrent events (combined outcome of stroke progression or distinct recurrent stroke) within 90 days. Imaging parameters not included in the original CATCH imaging (CT/CTA and MRI) metrics were assessed for prediction of recurrent events. We also completed an exploratory analysis comparing predictors of symptom progression versus recurrence.

Results: There were 36 recurrent events (36/510, 7.1% (95%CI: 5.0-9.6)) including 19 progression and 17 recurrent strokes. On CT/CTA: white matter disease, prior stroke, aortic arch focal plaque≥4mm, or intraluminal thrombus did not predict recurrent events. On MRI: white matter disease, prior stroke, and microbleeds did not predict recurrent events. The only additional clinical predictor was symptom fluctuation (hazard ratio 2.3; 95% CI: 1.05-5.0). Parameters predicting symptom progression included: ongoing symptoms at initial assessment, symptom fluctuation, intracranial occlusion, intracranial occlusion or stenosis, and the CT/CTA metric. No parameter was strongly predictive of recurrent stroke.

Conclusions: There was no imaging parameter that could improve upon our original CT/CTA or MRI metrics to predict recurrent events after TIA and minor stroke. Only the addition of symptom fluctuation to the CT/CTA metric improved the prediction of recurrent events. Imaging was more predictive of symptom progression than distinct recurrent events.

Validation of a self-report comorbidity questionnaire for multiple sclerosis

BACKGROUND/AIMS

Researchers increasingly recognize the high frequency of comorbidity in multiple sclerosis (MS) and the negative impact on quality of life and disability, but little work has evaluated methods of comorbidity measurement in MS. We aimed to validate a self-report questionnaire for assessing comorbidity in MS.

METHODS

Patients with MS were recruited from the MS Clinic in Winnipeg, Canada and the Mellen Center (Cleveland Clinic, Cleveland, Ohio, USA) from October 2008 to 2009. Using a questionnaire, participants reported the presence or absence of 36 comorbidities, sociodemographic characteristics, and disability status. Abstractors blinded to questionnaire results collected data regarding the comorbidities of interest and their treatments. Using the medical record as the gold standard, we determined the sensitivity, specificity, positive and negative predictive values of the questionnaire data. To measure agreement we calculated kappa (kappa) statistics.

RESULTS

We enrolled 404 participants. Agreement between self-report and medical records was high (kappa >0.82) for diabetes and hypertension; substantial (kappa = 0.62-0.80) for hyperlipidemia, thyroid disease, glaucoma, and lung disease; moderate (kappa = 0.43-0.56) for osteoporosis, irritable bowel syndrome, migraine, depression, heart disease, and anxiety disorders. Agreement was slight to fair for the remaining comorbidities.

CONCLUSIONS

Self-report is a valid way to capture comorbidities affecting MS patients.

Pathological evidence of vacuolar myelinopathy in a child following vigabatrin administration

Vigabatrin, a gamma-aminobutyric acid (GABA) aminotransferase- inhibiting drug used for seizure control, has been associated with white matter vacuolation and intramyelinic edema in animal studies. Similar pathological lesions have never been described in the central nervous system of human participants treated with the drug. Described here is a child with quadriparetic cerebral palsy secondary to hypoxic-ischemic brain injury following premature birth, who received vigabatrin for the treatment of infantile spasms at 9 months of age. A severe deterioration of neurologic function immediately followed the initiation of vigabatrin, and the child died 3 weeks later. Neuropathological examination revealed white matter vacuolation and intramyelinic edema. This represents the first reported case of vigabatrin-induced intramyelinic edema in humans. It validates the concerns regarding vigabatrin safety in infants and individuals with preexisting abnormalities of myelin.

Impact of land drainage on peatland hydrology

There is a long history of drainage of blanket peat but few studies of the long-term hydrological impact of drainage. This paper aims to test differences in runoff production processes between intact and drained blanket peat catchments and determine whether there have been any long-term changes in stream flow since drainage occurred. Hillslope runoff processes and stream discharge were measured in four blanket peat catchments. Two catchments were drained with open-cut ditches in the 1950s. Ditching originally resulted in shorter lag times and flashier storm hydrographs but no change in the annual catchment runoff efficiency. In the period between 2002 and 2004, the hydrographs in the drained catchments, while still flashy, were less sensitive to rainfall than in the 1950s and the runoff efficiency had significantly increased. Drains resulted in a distinctive spatial pattern of runoff production across the slopes. Overland flow was significantly lower in the drained catchments where throughflow was more dominant. In the intact peatlands, matrix throughflow produced by peat layers below 10 cm was rare and produced <1% of the runoff. However, in drained peatlands, matrix throughflow in deeper peat layers was common and provided around 23% of the runoff from gauged plots. Macropore flow, the density of soil piping, and pipeflow were significantly greater in drained peatlands than in intact basins. Gradual changes to peat structure could explain the long-term changes in river flow, which are in addition to those occurring in the immediate aftermath of peatland drainage.

Gas chromatographic, mass spectrometric and stable carbon isotopic investigations of organic residues of plant oils and animal fats employed as illuminants in archaeological lamps from Egypt

Man's use of illuminants in lamps or as torches to extend the working day and range of environments accessible to him would have been a major technological advance in human civilisation. The most obvious evidence for this in the archaeological record comes from pottery and stone vessels showing sooting due to the use of a wick in conjunction with a lipid-based fuel or illuminant. A wide range of potential fuels would have been exploited depending upon availability and burning requirements. Reported herein are the results of chemical investigations of a number of lamps recovered from excavations of the site of Qasr Ibrim, Egypt. Gas chromatographic, mass spectrometric and stable carbon isotopic analyses of both free (solvent extractable) and 'bound'(released from solvent extracted pottery by base treatment) lipids have revealed a wide range of saturated fatty acids, hydroxy fatty acids and alpha, omega-dicarboxylic acids. Examination of the distributions of compounds and comparisons with the fatty acid compositions of modern plant oils have allowed a range of fats and oils to be recognised. Specific illuminants identified include Brassicaceae (Cruciferae) seed oil (most likely radish oil, Raphanus sativus), castor oil (from Ricinus communis), animal fat, with less diagnostic distributions and delta(13)C values being consistent with low stearic acid plant oils, such as linseed (Linum usitatissimum) or sesame (Sesamum indicum) oils. The identifications of the various oils and fats are supported by parallel investigations of illuminant residues produced by burning various oils in replica pottery lamps. The findings are entirely consistent with the classical writers including Strabo, Pliny and Theophrastrus.

ADAM gene expression and regulation during human osteoclast formation

In this study, we identified the expression and the regulation of ADAM members (a disintegrin and metalloprotease) at both gene and protein levels during human osteoclast differentiation and activity. Human peripheral blood monocytes (HPBMC) treated with M-CSF and RANKL were used as an in vitro fusion model. In parallel, we used human osteoclastoma (OCL) tumor as a source of mature osteoclasts, and human osteoblastic cells as a control representing nonfusing and non-resorbing bone cells. RT-PCR using ADAM-specific primers enabled us to identify the expression of ADAM 8, 9, 10, 15, 17, and 28 in both osteoclasts and osteoblasts. Using primers specific for each ADAM 12 isoform (L and S), we observed a strong signal for both forms (ADAM 12L and ADAM 12S) in osteoblastic cells, while only ADAM 12S was detectable in HPBMC-derived osteoclasts and osteoclastoma. Gene regulation was studied using real-time PCR analysis performed during HPBMC differentiation; this showed a progressive increase of ADAM 12 mRNA level from day 1 to 8 of the culture, while at around day 9, ADAM 12 mRNA level decreased 2-fold. We also showed that ADAM 8, ADAM 17, and ADAM 28 decreased according to the stage of HPBMC differentiation or fusion. ADAM 10 was unaltered during cell fusion. However, confocal immunolocalization showed that ADAM 10 protein re-localized from the nuclei and cytoplasm to the plasma membrane during culture and to the ruffled border in resorbing cells. The same re-localization process was observed using an ADAM 12S-specific antibody during HPBMC differentiation. Between days 12 and 14, ADAM 12 co-localized with the F-actin ring, and at day 15, a strong signal was also present in ruffled border or sealing zone area of osteoclasts. Our results describe the expression and regulation of various ADAMs in human bone cells and the selective expression of ADAM 12L in osteoblasts. Our gene regulation and protein localization studies suggest a function for ADAM 10 and ADAM 12S in the formation of osteoclasts from HPBMC and resorption activity.

Targeting of biotinylated compounds to its target tissue using a low-density lipoprotein receptor–avidin fusion protein

The very high binding affinity of avidin to biotin is one of the highest to occur in nature. We constructed a fusion protein composed of avidin and the endocytotic LDL receptor in order to target biotinylated molecules to cells of the desired tissues. In addition to the native avidin, charge-mutated and nonglycosylated avidins were utilized as part of the fusion proteins, in order to modify its properties. All of the fusion protein versions retained the biotin-binding capacity. Although the specificity was not increased, however, fusion proteins composed of natural avidin and nonglycosylated avidin bound most efficiently to the biotinylated ligands. Fluorescence microscopy and atomic force microscopy studies revealed the expression of the fusion protein on cell membranes, and demonstrated specific and high-affinity binding of biotin to the low-density lipoprotein receptor (LDLR)-avidin fusion protein in vitro. Additionally, systemically administered biotinylated ligand targeted with high specificity the intracerebral tumors of rats that were expressing fusion protein after the virus-mediated gene transfer. These results suggest that local gene transfer of the fusion protein to target tissues may offer a novel tool for the delivery of biotinylated molecules in vitro and in vivo for therapeutic and imaging purposes.

The development and use of a triage protocol for patients with dental problems contacting an out-of-hours general medical practitioner cooperative

PURPOSE OF THE STUDY

The number of patients contacting general medical practitioner (GMP) out-of-hours services with dental problems is perceived to be a significant problem by the medical profession. This study was undertaken to design and pilot a triage protocol that could be used by non-dental staff to refer callers with dental complaints for appropriate treatment.

BASIC PROCEDURES

A triage protocol was designed to address the patient conditions considered to be relevant to emergency dental care. The triage protocol was piloted for three months at a GMP cooperative in North Wales, which provided an out-of-hours service for 61 GMPs. Baseline data were collected for three months prior to the introduction of the triage protocol.

MAIN FINDINGS

The study showed that the number of dental callers contacting the out-of-hours service was not as great as GMPs imagined, and was similar to other studies. The introduction of the triage protocol resulted in a rise in the number of callers asked to call the general dental practitioner (GDP) support line. The number of unregistered patients given the name of a dentist also increased. The need to make a second telephone call seemed not to affect patient satisfaction since when patients were later questioned on their experience, those who had used the service since the introduction of the triage protocol were more likely to be satisfied with the service.

PRINCIPAL CONCLUSIONS

This study provides some evidence that a triage protocol can be used successfully by non-dental staff to sift requests for out-of-hours emergency dental care.

Cell adhesion molecules in human osteoblasts: structure and function

Osteoblasts and bone lining cells form a near continuous layer covering the bone surface and interactions between these cells and the organic matrix of bone are important determinants of osteoblast proliferation and differentiation. In addition, cells of the osteoblast-lineage form functional communications with each other, with the extra-cellular matrix and with osteocytes through cytoplasmic processes extending through canaliculi in the bone. Together, these cells form a network of putative importance in the regulation of skeletal homeostasis. Cell-cell and cell-matrix interactions are mediated by members of several families of cell adhesion molecules, and knowledge of their interactions will be of fundamental importance in understanding the role of osteoblast in skeletal turnover. Here, the expression pattern of members of the major families of cell adhesion molecules by cells of the osteoblast lineage is reviewed. Special emphasis has been placed on human tissues. In addition, the possibility that cells at progressive stages of the osteoblast lineage have different profiles of cell adhesion molecule expression is explored, and the putative significance of cell-matrix interactions in human skeletal disease briefly discussed.

Effect of selective or combined inhibition of integrins alpha(IIb)beta(3) and alpha(v)beta(3) on thrombosis and neointima after oversized porcine coronary angioplasty

BACKGROUND

Thrombosis and neointima formation limit the efficacy of coronary angioplasty (PTCA). Clinical trials have implicated the adhesion molecules integrin alpha(IIb)beta(3) and integrin alpha(v)beta(3) in these processes. The roles of these molecules in vascular smooth muscle cell adhesion, platelet aggregation, and the thrombotic and neointimal response to oversize porcine PTCA was investigated by use of a selective alpha(IIb)beta(3) antagonist (lamifiban), a selective alpha(v)beta(3) antagonist (VO514), and a combined alpha(IIb)beta(3)/alpha(v)beta(3) antagonist (G3580).

METHODS AND RESULTS

In vitro, both alpha(v)beta(3) inhibitors caused dose-dependent inhibition of porcine vascular smooth muscle cell adhesion to vitronectin but not to collagen type IV, fibronectin, or laminin, whereas selective alpha(IIb)beta(3) inhibition had no effect. Intravenous infusions of either alpha(IIb)beta(3) inhibitor in swine profoundly inhibited ex vivo platelet aggregation to ADP, whereas selective alpha(v)beta(3) inhibition had no effect. In a porcine PTCA model, intravenous infusions of the integrin antagonists were administered for 14 days after oversized balloon angioplasty injury. After PTCA, there was regional upregulation of integrin alpha(v)beta(3) in the developing neointima, as assessed by immunohistochemistry. Six hours after PTCA, obstruction of lumen by thrombus was reduced significantly by alpha(IIb)beta(3) inhibition compared with either control or alpha(v)beta(3) inhibition (mean control, 18.7%; VO514, 18.5%; lamifiban, 6.4%; G3580, 7.9%). Twenty-eight days after PTCA, there was a significant reduction of neointima with inhibitors of either integrin (mean intima/media ratio: control, 3.08; VO514, 1.33; lamifiban, 0.97; G3580, 1.32).

CONCLUSIONS

We conclude that both integrin alpha(IIb)beta(3) and integrin alpha(v)beta(3) participate in neointima development after experimental angioplasty.

Opinions and experiences in general practice on osteoporosis prevention, diagnosis and management

We determined to survey the general practice population regarding their attitudes to and knowledge of osteoporosis as a baseline prior to publication of national guidelines for the management of osteoporosis. All 2515 general practitioners registered in the 10 Health Authorities of the North Thames region, London, UK were surveyed by a postal questionnaire. Responses relating to epidemiology, public health and education on osteoporosis were analyzed. The overall response was 1153 (46%). General practitioners who responded were younger, predominantly female and in group practice. There is considerable awareness of the importance of preventing osteoporosis. General practitioners are active in identifying groups at risk, particularly those who are aged 40 years and older. A prevention strategy for osteoporosis is viewed as effective. However, two thirds of general practitioners remain unconvinced about the efficacy of drug therapy. Education on osteoporosis is considered inadequate. General practitioners would welcome further information on management issues and access to osteoporosis services. In conclusion, educational initiatives will be important both at undergraduate and postgraduate levels to increase awareness and knowledge of osteoporosis. General practitioners are aware of the public health impact of this condition and express a preference for educational material of direct relevance to the care of their patients. Therefore better cooperation between primary and secondary care should lead to ways of breaking down barriers to change in clinical practice and promoting fully integrated care of patients with osteoporosis.

Survival advantage of stentless aortic bioprostheses

BACKGROUND

Bioprostheses (BPs) are used to avoid anticoagulation after aortic valve replacement (AVR) in patients over 65 years of age. Stentless BPs offer established hemodynamic benefits. We sought to determine whether these advantages translate into improved survival.

METHODS

Between 1993 and 1997, follow-up data (for Food and Drug Administration submission) were collected prospectively for 160 consecutive, unselected hospital survivors who received the Freestyle valve (FS). Equivalent data were collected for 247 Carpentier-Edwards (CE) porcine xenograft patients. Detailed comparative statistical analysis was used to compare events and survival between the groups. Follow-up was 100% complete for the FS (5.2 years maximum; mean 3.2+/-1.0 years) group and 98% (7.2 years maximum; mean 3.8+/-2.0 years) for CE.

RESULTS

The groups were well matched in age (FS, 73+/-6 years; CE, 74+/-6 years), gender (FS, 58% male; CE, 62% male), ventricular function, and number of patients requiring coronary grafts (FS, 41%; CE, 37%). Actuarial survival at 5 years was 84% for FS versus 69% for CE (p = 0.023 Kaplan Meier, p = 0.009 Cox). Annual mortality rates were 3.6% for FS versus 7.1% for CE (p = 0.001). Thromboembolic rate was 0.8% per year for FS and 2.4% for CE (p = 0.024) without a difference in cardiac rhythm. Incidence of nonstructural dysfunction (paravalvular leak) was 0.2% for FS versus 1.3% for CE (p = 0.020).

CONCLUSIONS

By 5 years, the stentless valve patients had improved survival and reduced adverse events. Though differences in durability are yet to be proved, our findings support the use of stentless bioprostheses in this age group.

Mechanical bridge to recovery in fulminant myocarditis

A patient with acute fulminant lymphocytic myocarditis and cardiogenic shock was successfully treated by mechanical off loading of the left ventricle. A nonpulsatile left-heart bypass was undertaken with an implantable centrifugal blood pump. Careful weaning resulted in device removal on the seventh day. Left and right ventricular function is sustained at 7 months. Widespread application of this method depends on the availability of an inexpensive user friendly blood pump, appropriate weaning protocols and emerging strategies to promote sustainable myocardial recovery.

Smooth muscle cell matrix metalloproteinase production is stimulated via alpha(v)beta(3) integrin

This study tests the hypothesis that alpha(v)beta(3) integrin receptors play a critical role in smooth muscle cell (SMC) migration after arterial injury and facilitate migration through the upregulation of matrix metalloproteinase (MMP) activity. We showed that beta(3) integrin mRNA was upregulated by SMCs in the balloon-injured rat carotid artery in coincidence with MMP-1 expression and early SMC migration. Treatment with the beta(3) integrin-blocking antibody F11 significantly decreased SMC migration into the intima at 4 days after injury, from 110.8+/-30.8 cells/mm(2) in control rats to 10.29+/-7.03 cells/mm(2) in F11-treated rats (P=0.008). By contrast, there was no effect on medial SMC proliferation or on medial SMC number in the carotid artery at 4 days. In vitro, we found that human newborn SMCs produced MMP-1 but that adult SMCs did not. This was possibly due to the fact that newborn SMCs expressed alpha(v)beta(3) integrin receptors, whereas adult SMCs did not. Stimulation of newborn (alpha(v)beta(3)+) SMCs with osteopontin, a matrix ligand for alpha(v)beta(3), increased MMP-1 production from 114.4+/-35.8 ng/mL at 0 nmol/L osteopontin to 232.5+/-57.5 ng/mL at 100 nmol/L osteopontin. Finally, we showed that stimulation of newborn SMCs with platelet-derived growth factor-BB and osteopontin together increased the SMC production of MMP-9. Thus, our results support the hypothesis that SMC alpha(v)beta(3) integrin receptors play an important role in regulating migration by stimulating SMC MMP production.

Community control of Chlamydia trachomatis

In order to determine the amount of Chlamydia trachomatis that is diagnosed outside genitourinary medicine (GUM) clinics in a large university city, a review of all positive chlamydial infections diagnosed on specimens received from hospitals (non-GUM) and community sources in 1996 was performed. It was also ascertained whether these patients subsequently attended at GUM. Eight hundred and nine cases of C. trachomatis were diagnosed during the study period. Three hundred and ninety-seven (49%) were initially diagnosed outside GUM of which 264 (66.5%) were referred, giving an overall involvement of GUM in 667 (83.6%) of all cases. The proportion of cases referred varied according to service: Family Planning Clinics 94.5%, Obstetrics and Gynaecology 73%, General Practice 52.5%. Referral rates also showed within service variation, with University Health Services referring 19% vs 73% (P < 0.001). High levels of referral to GUM of patients diagnosed with C. trachomatis are achievable, but referrals show inter- and intra-service variations. Efforts should be made to improve referral rates from those services with the lowest rates.

IN CONCLUSION

(1) The proportion of cases of C. trachomatis diagnosed in the community who are referred to a GUM clinic, varies according to service type. (2) Referral rates vary within services and (3) Distance of services from a GUM clinic does not appear to influence referral rates.

The pharmacokinetics of ziprasidone in subjects with normal and impaired renal function

AIMS

To assess whether renal impairment influences the pharmacokinetics of ziprasidone, and to determine whether ziprasidone is cleared via haemodialysis.

METHODS

Thirty-nine subjects with varying degrees of renal impairment were enrolled into an open-label, multicentre, multiple-dose study and assigned to four groups according to their renal function: normal (group 1, creatinine clearance > 70 ml min(-1); mildly impaired (group 2, creatinine clearance 30-60 ml min(-1); moderately impaired (group 3, creatinine clearance 10-29 ml min(-1), and severely impaired (group 4, requiring haemodialysis three times-a-week). Subjects received ziprasidone 40 mg day(-1), given orally with food, as two divided daily doses for 7 days and a single 20 mg dose on the morning of day 8. Pharmacokinetic variables were determined from multiple venous blood samples collected on days 1 and 8 (haemodialysis day for subjects with severe renal impairment). Additional samples were collected from subjects with severe renal impairment on day 7 (nonhaemodialysis day).

RESULTS

On day 1 there were no statistically significant differences in the pharmacokinetics (AUC(0, 12 h), Cmax, tmax) of ziprasidone among subjects with normal renal function and those with mild, moderate and severe renal impairment. The AUC(0,12 h) and Cmax in subjects with mildly impaired renal function were statistically significantly greater than in those with moderately impaired renal function (P = 0.0163-0.0385). The mean AUC(0,12 h) was 272, 370, 250 and 297 ng ml(-1) h in groups 1, 2, 3 and 4, respectively. Corresponding mean Cmax values were 47, 61, 41 and 50 ng ml(-1) and corresponding mean tmax values were 5, 6, 5 and 5 h. On day 8 there were no statistically significant differences in the pharmacokinetics (AUC(0,12 h), Cmax, tmax, lambda(z), Fb) of ziprasidone among subjects with normal renal function and those with moderate or severe renal impairment. The AUC(0,12 h) in subjects with mild renal impairment was statistically significantly greater than those in the other three groups (P = 0.0025-0.0221), but this was not considered clinically significant. The mean AUC(0,12 h) were 446, 650, 389 and 427 ng ml(-1) h in groups 1, 2, 3 and 4, respectively. Corresponding mean Cmax values were 68, 93, 54 and 70 ng ml(-1), corresponding mean tmax values were 4, 5, 4 and 5 h and corresponding mean lambda(z) were 0.14, 0.11, 0.14 and 0.17 h(-1). The mean percentage Fb was 99.84-99.88% across all groups and the mean t(1/2),z ranged from 4.2 to 6.4 h. Comparison of the mean AUC(0,12 h) and Cmax values in subjects with severe renal impairment on day 7 with those on day 8 suggested that haemodialysis does not have a clinically significant effect on the pharmacokinetics of ziprasidone.

CONCLUSIONS

The findings of this study indicate that mild-to-moderate impairment of renal function does not result in clinically significant alteration of ziprasidone pharmacokinetics and therefore does not necessitate dose adjustment.

Pharmacokinetics of oral and intravenous dolasetron mesylate in patients with renal impairment

In an open-label, randomized, two-way complete crossover study, the influence of renal impairment on the pharmacokinetics of dolasetron and its primary active metabolite, hydrodolasetron, were evaluated. Patients with renal impairment were stratified into three groups of 12 based on their 24-hour creatinine clearance (Cl(cr)): group 1, mild impairment (Cl(cr) between 41 and 80 mL/min); group 2, moderate impairment (Cl(cr) between 11 and 40 mL/min); and group 3, endstage renal impairment (Cl(cr) < or = 10 mL/min). Twenty-four healthy volunteers from a previous study served as the control group. Each participant received a single intravenous or oral 200-mg dose of dolasetron mesylate on separate occasions. Serial blood samples were collected up to 60 hours after dose for determination of dolasetron and hydrodolasetron, and urine samples were collected in intervals up to 72 hours for determination of dolasetron, hydrodolasetron, and the 5' and 6'-hydroxy metabolites of hydrodolasetron. Because plasma concentrations were low and sporadic, pharmacokinetic parameters of dolasetron were not calculated after oral administration. Although some significant differences in area under the concentration-time curve (AUC0-infinity), volume of distribution (Vd), systemic clearance (Cl), and elimination half-life (t1/2) of the parent drug were observed between control subjects and patients with renal impairment, there were no systematic findings related to degree of renal dysfunction. The elimination pathways of hydrodolasetron include both hepatic metabolism and renal excretion. Consistent increases in mean Cmax, AUC0-infinity, and t1/2 and decreases in renal and total apparent clearance of hydrodolasetron were seen with diminishing renal function after intravenous administration of dolasetron mesylate. No consistent changes were found after oral administration. Urinary excretion of hydrodolasetron and its metabolites decreased with decreasing renal function, but the profile of metabolites remained constant. Dolasetron was well tolerated in all three groups of patients. Based on these findings, no dosage adjustment for dolasetron is recommended in patients with renal impairment.

Unusual abscess patterns following dropped gallstones during laparoscopic cholecystectomy

BACKGROUND

Laparoscopic cholecystectomy has become the standard treatment for symptomatic cholelithiasis. Numerous clinical trials have deemed it a safe procedure, regardless of the known increased risk of bile duct injury. However, the consequences and incidence of less well-known complications are still being addressed.

METHODS

Between 1993 and 1995, 1,130 laparoscopic cholecystectomies were performed at two major metropolitan medical centers. Of these patients, we know of 3 (0.3%) who subsequently developed abscesses as a consequence of dropped stones during the laparoscopic cholecystectomy. One additional patient who underwent prior laparoscopic cholecystectomy at another institution developed late infection as well.

RESULTS

All 4 patients developed late purulent abscesses that ultimately required open surgical drainage, and 1 patient developed trocar site "tumor" masses that were secondary to inflammatory tissue around gallstone fragments. All patients were successfully treated by surgical drainage, stone removal, and antibiotics. Trocar site inflammatory masses required excision only. Significant costs were involved in the diagnosis, management, and duration of therapy for these problems.

CONCLUSIONS

This experience closely resembles that of other centers and points out the existence of a late postoperative complication following laparoscopic cholecystectomy that was rarely encountered with open cholecystectomy. Strategies for avoiding this problem are discussed. Whether dropped stones are an indication for conversion to open cholecystectomy remains unclear. Thorough irrigation at time of laparoscopic cholecystectomy with or without placement of a drain in the subhepatic space does not prevent this complication.

Transport in vitro fertilization and intracytoplasmic sperm injection: results of a collaborative trial

OBJECTIVE

To determine whether the use of a central assisted reproduction laboratory, with gamete transport to the facility (transport assisted reproduction), would decrease oocyte quality or performance in IVF-ET and intracytoplasmic sperm injection (ICSI).

DESIGN

Retrospective clinical study.

SETTING

Public and private fertility clinics.

PATIENT(S)

A total of 467 couples underwent transport IVF, whereas 108 underwent transport ICSI. A group of 60 couples underwent conventional IVF during the same period. All methods and protocols used were similar among centers. Oocyte pick-up was performed by ultrasound-guided vaginal puncture.

INTERVENTION(S)

Oocytes were transported under controlled conditions, from the site of follicular aspiration to a central laboratory.

MAIN OUTCOME MEASURE(S)

The fertilization and cleavage rates and clinical pregnancies were compared among the study populations.

RESULT(S)

The differences between the fertilization and cleavage rates of ova and the rates of clinical pregnancies produced by transport and conventional methods were not statistically significant.

CONCLUSION(S)

Gamete transport to a central laboratory was not harmful for oocytes or for the outcome of assisted reproduction. Transport makes the use of IVF and ICSI available to physicians who are not affiliated with an assisted reproduction program, reduces costs, and increases acceptability of the procedures to patients.

Renal dysfunction does not alter the pharmacokinetics or LDL-cholesterol reduction of atorvastatin

The objective of this study was to determine the effects of renal dysfunction on the steady-state pharmacokinetics and pharmacodynamics of atorvastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor. Nineteen subjects with calculated creatinine clearances ranging from 13 mL/min to 143 mL/min were administered 10 mg atorvastatin daily for 2 weeks. Pharmacokinetic parameters and lipid responses were analyzed by regression on calculated creatinine clearance. Correlations between steady-state atorvastatin pharmacokinetic or pharmacodynamic parameters and creatinine clearance were weak and, in general, did not achieve statistical significance. Although the elimination rate constant, lambda z (0.579), was significantly correlated with creatinine clearance, neither maximum plasma concentration (Cmax, -0.361) nor oral clearance (Cl/F, 0.306) were; thus, steady-state exposure is not altered. Renal impairment has no significant effect on pharmacodynamics and pharmacokinetics of atorvastatin.

Genital Chlamydia trachomatis infections in primary care

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