Predictors of maternal and fetal outcome in severely anemic pregnant mothers: A sequential mixed methods study

Introduction

Severe anemia in pregnancy increases maternal and neonatal morbidity and mortality in the antenatal period.

Objective

To find out the maternal and fetal outcomes in severely anemic pregnant women and explore the reason for the persistence of severe anemia in pregnant women.

Materials and Methods

Sequential explanatory mixed method study (Quan-Qual) was conducted in the Government Women and Children Hospital for a period of 1 and half years. Most of the people were from rural backgrounds and belonging to low socioeconomic status have been registered. Quantitative data were collected from 125 severe anemic cases; a consecutive sampling technique was applied. In-depth interviews were conducted among purposively selected severe anemic patients (n = 15) who were vocal and willing to explore the reason for the persistence of anemia. The interviews were conducted till the point of saturation. Ethical principles were adhered throughout the study. Quantitative data were anlyzed using SPSS software. Manual content analysis was done for qualitative data.

Results

Among 125 severe anemic patients, 12.8% patients had preterm labour, about 23.2% had inadequate lactation, and 13.6% had a puerperal febrile illness. It was found 41.6% of neonates had respiratory distress and 33.6% had the refusal of feeds. When compared to vaginal delivery, women undergoing cesarean section have 3.2 times (95% confidence interval 1.39-7.32) higher odds of developing maternal complications. Nagelkerke's R2 value for the model was 11.1%. Five broad categories namely Family centric nature, Lack of awareness, Pill burden, Food Fads, and Myths related to iron intake emerged from the study.

Conclusion

Complications can occur in mothers and neonates if anemia is not corrected in early trimester.

Unheard Voices of Pregnant Health Care Professionals during COVID-19 Pandemic? - A Qualitative Study

Background

Pregnant Health Care Professionals (HCPs), who serve as front-line warriors of COVID-19 will invariably experience a stressful pregnancy period. Ensuring their well-being during this COVID-19 pandemic period is a big challenge and guidelines or standard operating procedures (SOP) for the same are non-existent or are scarce.

Objectives

To explore the challenges and experiences of pregnant HCPs during the COVID-19 pandemic.

Methods

A qualitative study was conducted among 19 pregnant HCPs (14 Doctors and 5 staff nurses) working in Pondicherry, who were selected using purposive sampling for in-depth interviews. After obtaining informed written consent, face-to-face interviews were conducted until the attainment of the point of saturation. Audio recordings of the interviews were transcribed in English. Transcripts were proofread and manually analyzed for content. Codes obtained from the analysis of transcripts were merged to form broad categories.

Results

The majority 15 (78.9%) of HCPs belonged to the clinical department and had work experience from 2-4 years. The mean age of the respondents was 29.4 ± 3.6 years. Four broad categories (of challenges), namely, Personnel level (Fear of infection in workplace, Inadequate antenatal care), Family level (Family pressure to quit job, Guilt of spreading the infection to family members), society level (Criticism by neighbor for working, Stigma), and work level challenges (Fear of losing the job, Uncomfortable work environment) emerged from the study.

Conclusion and Recommendations

Challenges faced by the pregnant HCPs due to their nature of work remain by and large not addressed. Hence, specific guidelines or SOPs addressing these issues of pregnant health care workers and their swift and strict implementation are the need of the hour.

Analysing associations between digitalization and the accomplishment of the Sustainable Development Goals

Sustainability is a very complex concept made up of a multitude of interacting aspects that do not necessarily work synergistically with each other. The consequential outcome of cross-cutting drivers, such as digitalisation, is often difficult to assess, as the achievement of certain targets may also inadvertently hinder progress towards others. This investigation describes a comprehensive and systematic country-based analysis of statistical associations between digitalization and sustainability indicators operating at three different levels (i.e., index, goal and indicators). Results showed strong correlations between the composite indices for digitalization (IDI Development Index), sustainability (SDG Index from) and economic growth (GCI and GDP). However, the analysis of lower-level indicators provides a more ambiguous picture, with 2 of the sustainability goals and 22 % of the sustainability indicators included in the SDG Index showing negative associations with digitalisation. It appears that while synergies are generated in aspects related to economic and social sustainability, trade-offs occur in areas related to environmental protection such as climate change, depletion of natural resources and waste generation due to their negative associations with existing economic development models. These structural obstacles need to be acknowledged and adequately managed in order to ensuring harmonious and integral progress towards effective sustainability.

Glucose-to-Lymphocyte Ratio (GLR) as a Predictor of Preoperative Central Lymph Node Metastasis in Papillary Thyroid Cancer Patients With Type 2 Diabetes Mellitus and Construction of the Nomogram

Background

Detection of metastasis of central lymph nodes in papillary thyroid cancer is difficult before surgery. The role of routine or preventive central lymph node dissection in the management of papillary thyroid cancer remains inconclusive. Moreover, glucose metabolism and systemic inflammation are related to the aggressiveness of several malignant tumors and the prognoses of these patients. This study aimed to construct a nomogram based on the readily available preoperative clinical features for predicting the occurrence of preoperative central lymph node metastasis in patients with papillary thyroid cancer and type 2 diabetes mellitus. The findings may underlie clinical implications for determining the appropriate treatment strategies for these patients.

Methods

A total of 419 patients were enrolled. We used the receiver operating characteristic curves to determine the best cut-off value and converted the continuous into categorical variables. Next, a single-factor logistic analysis for the independent variables was performed, following which a multivariate regression analysis was conducted for the selected significant risk factors. Finally, the nomogram was constructed and verified using external data; the existing data were compared with the original model.

Results

According to the receiver operating characteristic curves, the best cut-off values ​​for glucose-to-lymphocyte ratio and tumor size were 4.23 cm and 0.95 cm, respectively. Findings from the multivariate logistic regression analysis suggested that age, bilateral tumors, maximum tumor size, and the ratio of glucose-to-lymphocytes were independent risk factors for preoperative central lymph node metastasis. The C-indexes in the training and the external validation data sets were 0.733 and 0.664, respectively. Both calibration curves and the Hosmer-Lemeshow tests indicated that the model was well-calibrated. Through decision curve analysis, the predictive model was estimated to have strong clinical applicability and greater benefits. To compare the performance of the new with that of the original model, we performed a net reclassification index and the integrated discrimination improvement analyses, both of which indicated that the new model had a better predictive ability.

Conclusion

In patients with type 2 diabetes mellitus and papillary thyroid cancer, a high preoperative glucose-to-lymphocyte ratio was an independent predictor of the preoperative central lymph node metastasis. The nomogram so constructed could better predict the preoperative central lymph node metastasis in these patients.

Measures for evaluation of prognostic improvement under multivariate normality for nested and nonnested models

When comparing performances of two risk prediction models, several metrics exist to quantify prognostic improvement, including the change in the area under the Receiver Operating Characteristic curve, the Integrated Discrimination Improvement, the Net Reclassification Index at event rate, the change in Standardized Net Benefit, the change in Brier score, and the change in scaled Brier score. We explore the behavior and interrelationships between these metrics under multivariate normality in nested and nonnested model comparisons. We demonstrate that, within the framework of linear discriminant analysis, all six statistics are functions of squared Mahalanobis distance, a robust metric that properly measures discrimination by quantifying the separation between the risk scores of events and nonevents. These relationships are important for overall interpretability and clinical usefulness. Through simulation, we demonstrate that the performance of the theoretical estimators under normality is comparable or superior to empirical estimation methods typically used by investigators. In particular, the theoretical estimators for the Net Reclassification Index and the change in Standardized Net Benefit exhibit less variability in their estimates as compared to their empirically estimated counterparts. Finally, we explore how these metrics behave with potentially nonnormal data by applying these methods in a practical example based on the sex-specific cardiovascular disease risk models from the Framingham Heart Study. Our findings aim to give greater insight into the behavior of these measures and the connections existing among them and to provide additional estimation methods with less variability for the Net Reclassification Index and the change in Standardized Net Benefit.

Asymptotic distribution of ∆AUC, NRIs, and IDI based on theory of U-statistics

The change in area under the curve (∆AUC), the integrated discrimination improvement (IDI), and net reclassification index (NRI) are commonly used measures of risk prediction model performance. Some authors have reported good validity of associated methods of estimating their standard errors (SE) and construction of confidence intervals, whereas others have questioned their performance. To address these issues, we unite the ∆AUC, IDI, and three versions of the NRI under the umbrella of the U-statistics family. We rigorously show that the asymptotic behavior of ∆AUC, NRIs, and IDI fits the asymptotic distribution theory developed for U-statistics. We prove that the ∆AUC, NRIs, and IDI are asymptotically normal, unless they compare nested models under the null hypothesis. In the latter case, asymptotic normality and existing SE estimates cannot be applied to ∆AUC, NRIs, or IDI. In the former case, SE formulas proposed in the literature are equivalent to SE formulas obtained from U-statistics theory if we ignore adjustment for estimated parameters. We use Sukhatme-Randles-deWet condition to determine when adjustment for estimated parameters is necessary. We show that adjustment is not necessary for SEs of the ∆AUC and two versions of the NRI when added predictor variables are significant and normally distributed. The SEs of the IDI and three-category NRI should always be adjusted for estimated parameters. These results allow us to define when existing formulas for SE estimates can be used and when resampling methods such as the bootstrap should be used instead when comparing nested models. We also use the U-statistic theory to develop a new SE estimate of ∆AUC. Copyright © 2017 John Wiley & Sons, Ltd.

Net Reclassification Index and Integrated Discrimination Index Are Not Appropriate for Testing Whether a Biomarker Improves Predictive Performance

One of the goals of the Critical Path Institute's Predictive Safety Testing Consortium (PSTC) is to promote best practices for evaluating novel markers of drug induced injury. This includes the use of sound statistical methods. For rat studies, these practices have centered around comparing the area under the receiver-operator characteristic curve for each novel injury biomarker to those for the standard markers. In addition, the PSTC has previously used the net reclassification index (NRI) and integrated discrimination index (IDI) to assess the increased certainty provided by each novel injury biomarker when added to the information already provided by the standard markers. Due to their relatively simple interpretations, NRI and IDI have generally been popular measures of predictive performance. However recent literature suggests that significance tests for NRI and IDI can have inflated false positive rates and thus, tests based on these metrics should not be relied upon. Instead, when parametric models are employed to assess the added predictive value of a new marker, following (Pepe, M. S., Kerr, K. F., Longton, G., and Wang, Z. (2013). Testing for improvement in prediction model performance. Stat. Med. 32, 1467-1482), the PSTC recommends that likelihood based methods be used for significance testing.

Discrimination slope and integrated discrimination improvement - properties, relationships and impact of calibration

Discrimination slope, defined as the slope of a linear regression of predicted probabilities of event derived from a prognostic model on the binary event status, has recently gained popularity as a measure of model performance. It is as a building block for the integrated discrimination improvement that equals the difference in discrimination slopes between the two models being compared. Several authors have pointed out that it does not make sense to apply the integrated discrimination improvement and discrimination slope when working with mis-calibrated models, whereas others have raised concerns about the ability of improving discrimination slope without adding new information. In this paper, we show that under certain assumptions the discrimination slope is asymptotically related to two other R-squared measures, one of which is a rescaled version of the Brier score, known to be proper. Furthermore, we illustrate how a simple recalibration makes the slope equal to the rescaled Brier R-squared metric. We also show that the discrimination slope can be interpreted as a measure of reduction in expected regret for the Gini-Brier regret function. Using theoretical and practical examples, we illustrate how all of these metrics are affected by different levels of model mis-calibration. In particular, we demonstrate that simple recalibration ascertaining calibration in-the-large and calibration slope equal to 1 are not sufficient to correct for some forms of mis-calibration. We conclude that R-squared metrics, including the discrimination slope, offer an attractive choice for quantifying model performance as long as one accounts for their sensitivity to model calibration. Copyright © 2016 John Wiley & Sons, Ltd.

Risk stratification for cardiac complications in patients hospitalized for community-acquired pneumonia

OBJECTIVE

To derive and validate a clinical rule that stratifies the risk of cardiac complications in patients hospitalized for community-acquired pneumonia (CAP) and compare its performance to the pneumonia severity index (PSI) score.

PATIENTS AND METHODS

Two cohorts of patients hospitalized for CAP were selected for the study. We used regression techniques in the derivation cohort (1343 patients enrolled in the Pneumonia Patient Outcomes Research Team study between October 1991 and March 1994) to generate a prediction rule that we validated in the validation cohort (608 patients enrolled in the Dissemination of Guidelines for Length of Stay study between February 1998 and March 1999). Discrimination and reclassification analyses compared its performance against the PSI score.

RESULTS

A prediction model for cardiac complications in the derivation cohort included age, 3 preexisting conditions, 2 vital signs, and 7 common laboratory or radiographic parameters. Discrimination (C statistic, 0.81; 95% CI, 0.78-0.84) and calibration (Hosmer-Lemeshow goodness-of-fit test, χ(2)=13.0; P=.11) were good. We derived a point score system from this model that when applied to the validation cohort also had good discrimination (C statistic, 0.78; 95% CI, 0.74-0.83) and calibration (Hosmer-Lemeshow, χ(2)=9.0; P=.34). On the basis of this score, we defined 4 categories of incremental risk of cardiac complications. The incidence of cardiac complications across risk categories increased linearly (from lowest to highest) in both the derivation (3.0%, 17.8%, 35.2%, and 72.2%) and validation (5.0%, 8.2%, 28.3%, and 48.9%) cohorts (Cochran-Armitage linear trend test, P<.01). The new score outperformed the PSI score in predicting cardiac complications in the validation cohort (C statistic, 0.78 vs 0.74; P=.03; proportion of patients correctly reclassified by the new score, 44%).

CONCLUSION

We derived and validated a clinical rule that accurately stratifies the risk of cardiac complications in patients hospitalized for CAP.

Characteristics and outcomes of patients who achieve high workload (≥10 metabolic equivalents) during treadmill exercise echocardiography

OBJECTIVE

To determine the frequency and prognostic significance of abnormal exercise echocardiographic results for patients achieving a workload of 10 or more metabolic equivalents during treadmill exercise echocardiography.

PATIENTS AND METHODS

Patients who underwent treadmill exercise echocardiography from November 1, 2003, through December 31, 2008, and exercised for 9 or more minutes using the Bruce protocol (N=7236) were included. Clinical and exercise echocardiographic characteristics and outcomes were evaluated. Variables associated with abnormal exercise echocardiographic results and mortality were identified.

RESULTS

Exercise echocardiographic results were positive for ischemia in 862 patients (12%). Extensive ischemia developed in 265 patients (4%). For patients with normal exercise echocardiographic results, all-cause and cardiovascular mortality rates were 0.30% and 0.05% per person-year of follow-up, respectively. For patients who had extensive ischemia, all-cause and cardiovascular mortality rates were 0.84% and 0.25% per person-year of follow-up, respectively. Patients at highest risk were those who had extensive and severe regional wall motion abnormalities at rest (n=58), and their all-cause and cardiovascular mortality rates were 2.65% and 0.76% per person-year of follow-up. Exercise echocardiographic variables did not identify sizable patient subgroups at risk for death and did not provide incremental prognostic information (C statistic was 0.74 compared with 0.73 for the clinical plus exercise electrocardiography model).

CONCLUSION

Patients achieving a workload of 10 or more metabolic equivalents during treadmill exercise testing do not often have extensive ischemic abnormalities on exercise echocardiography. Although exercise echocardiographic results provide some prognostic information, it is not of incremental value for these patients, whose short-term and medium-term prognosis is excellent.

Vaccine efficacy of transcutaneous immunization with amyloid β using a dissolving microneedle array in a mouse model of Alzheimer’s disease. J Neuroimmunol. 2014;266:1-11. [PMID: 24315156 DOI: 10.1016/j.jneuroim.2013.11.002]

Vaccine therapy for Alzheimer's disease (AD) based on the amyloid cascade hypothesis has recently attracted attention for treating AD. Injectable immunization using amyloid β peptide (Aβ) comprising 1-42 amino-acid residues (Aβ1-42) as antigens showed therapeutic efficacy in mice; however, the clinical trial of this injected Aβ1-42 vaccine was stopped due to the incidence of meningoencephalitis caused by excess activation of Th1 cells infiltrating the brain as a serious adverse reaction. Because recent studies have suggested that transcutaneous immunization (TCI) is likely to elicit Th2-dominant immune responses, TCI is expected to be effective in treating AD without inducing adverse reactions. Previously reported TCI procedures employed complicated and impractical vaccination procedures; therefore, a simple, easy-to-use, and novel TCI approach needs to be established. In this study, we investigated the vaccine efficacy of an Aβ1-42-containing TCI using our novel dissolving microneedle array (MicroHyala; MH) against AD. MH-based TCI induced anti-Aβ1-42 immune responses by simple and low-invasive application of Aβ1-42-containing MH to the skin. Unfortunately, this TCI system resulted in little significant improvement in cognitive function and Th2-dominant immune responses, suggesting the need for further modification.

Association of coronary artery calcification with hepatic steatosis in asymptomatic individuals

OBJECTIVE

To determine the association of coronary artery calcification with hepatic steatosis in asymptomatic volunteers.

PATIENTS AND METHODS

The study group comprised 400 asymptomatic volunteers, enrolled from April 1, 2011, to September 30, 2012, without known coronary artery disease who were self-referred for screening noncontrast computed tomography to determine coronary calcium score (CCS). Computed tomographic images were used to determine the presence of hepatic steatosis. An a priori model was created to predict a CCS of 100 Agatston units (AU) or higher on the basis of Framingham risk factors, diabetes mellitus, and metabolic syndrome. Hepatic steatosis was then added to this model. Computation of the odds ratio (OR) for hepatic steatosis predicting a CCS of 100 AU or higher was performed. Finally, the OR for a CCS of 100 AU or higher being associated with hepatic steatosis was calculated.

RESULTS

When hepatic steatosis was added to traditional coronary risk factors, it was independently associated with a CCS of 100 AU or higher (OR, 2.85). This was greater than the OR of Framingham factors, diabetes mellitus, or metabolic syndrome. A CCS of 100 AU or higher was independently associated with an increased risk for hepatic steatosis (OR, 2.4). This OR was higher than traditional hepatic steatosis risk factors or metabolic syndrome.

CONCLUSION

Hepatic steatosis is a strong independent predictor of a CCS of 100 AU or higher in asymptomatic patients. It is associated with an increased risk of coronary artery disease beyond that expected from traditional coronary risk factors and/or metabolic syndrome. Additional studies are needed to clarify the role of hepatic steatosis as a possible independent risk factor for the development of coronary artery disease.

An automated model using electronic medical record data identifies patients with cirrhosis at high risk for readmission

BACKGROUND & AIMS

Patients with cirrhosis have 1-month rates of readmission as high as 35%. Early identification of high-risk patients could permit interventions to reduce readmission. The aim of our study was to construct an automated 30-day readmission risk model for cirrhotic patients using electronic medical record (EMR) data available early during hospitalization.

METHODS

We identified patients with cirrhosis admitted to a large safety-net hospital from January 2008 through December 2009. A multiple logistic regression model for 30-day rehospitalization was developed using medical and socioeconomic factors available within 48 hours of admission and tested on a validation cohort. Discrimination was assessed using receiver operator characteristic curve analysis.

RESULTS

We identified 836 cirrhotic patients with 1291 unique admission encounters. Rehospitalization occurred within 30 days for 27% of patients. Significant predictors of 30-day readmission included the number of address changes in the prior year (odds ratio [OR], 1.13; 95% confidence interval [CI], 1.05-1.21), number of admissions in the prior year (OR, 1.14; 95% CI, 1.05-1.24), Medicaid insurance (OR, 1.53; 95% CI, 1.10-2.13), thrombocytopenia (OR, 0.50; 95% CI, 0.35-0.72), low level of alanine aminotransferase (OR, 2.56; 95% CI, 1.09-6.00), anemia (OR, 1.63; 95% CI, 1.17-2.27), hyponatremia (OR, 1.78; 95% CI, 1.14-2.80), and Model for End-stage Liver Disease score (OR, 1.04; 95% CI, 1.01-1.06). The risk model predicted 30-day readmission, with c-statistics of 0.68 (95% CI, 0.64-0.72) and 0.66 (95% CI, 0.59-0.73) in the derivation and validation cohorts, respectively.

CONCLUSIONS

Clinical and social factors available early during admission and extractable from an EMR predicted 30-day readmission in cirrhotic patients with moderate accuracy. Decision support tools that use EMR-automated data are useful for risk stratification of patients with cirrhosis early during hospitalization.

Head-to-head comparison of 2 myocardial fibrosis biomarkers for long-term heart failure risk stratification: ST2 versus galectin-3

OBJECTIVES

ST2 and galectin-3 (Gal-3) were compared head-to-head for long-term risk stratification in an ambulatory heart failure (HF) population on top of other risk factors including N-terminal pro-B-type natriuretic peptide.

BACKGROUND

ST2 and Gal-3 are promising biomarkers of myocardial fibrosis and remodeling in HF.

METHODS

This cohort study included 876 patients (median age: 70 years, median left ventricular ejection fraction: 34%). The 2 biomarkers were evaluated relative to conventional assessment (11 risk factors) plus N-terminal pro-B-type natriuretic peptide in terms of discrimination, calibration, and reclassification analysis. Endpoints were 5-year all-cause and cardiovascular mortality, and the combined all-cause death/HF hospitalization.

RESULTS

During a median follow-up of 4.2 years (5.9 for alive patients), 392 patients died. In bivariate analysis, Gal-3 and ST2 were independent variables for all endpoints. In multivariate analysis, only ST2 remained independently associated with cardiovascular mortality (hazard ratio: 1.27, 95% confidence interval [CI]: 1.05 to 1.53, p = 0.014). Incorporation of ST2 into a full-adjusted model for all-cause mortality (including clinical variables and N-terminal pro-B-type natriuretic peptide) improved discrimination (C-statistic: 0.77, p = 0.004) and calibration, and reclassified significantly better (integrated discrimination improvement: 1.5, 95% CI: 0.5 to 2.5, p = 0.003; net reclassification index: 9.4, 95% CI: 4.8 to 14.1, p < 0.001). Incorporation of Gal-3 showed no significant increase in discrimination or reclassification and worse calibration metrics. On direct model comparison, ST2 was superior to Gal-3.

CONCLUSIONS

Head-to-head comparison of fibrosis biomarkers ST2 and Gal-3 in chronic HF revealed superiority of ST2 over Gal-3 in risk stratification. The incremental predictive contribution of Gal-3 to existing clinical risk factors was trivial.

High-sensitivity troponin T and risk stratification in patients with atrial fibrillation during treatment with apixaban or warfarin

OBJECTIVES

The aim of this study was to evaluate the prognostic value of high-sensitivity troponin T (hs-TnT) in addition to clinical risk factors and the CHA2DS2VASc (congestive heart failure, hypertension, 75 years of age and older, diabetes mellitus, previous stroke or transient ischemic attack, vascular disease, 65 to 74 years of age, female) risk score in patients with atrial fibrillation (AF).

BACKGROUND

The level of troponin is a powerful predictor of cardiovascular events and mortality.

METHODS

A total of 14,897 patients with AF were randomized to treatment with apixaban or warfarin in the ARISTOTLE (Apixaban for the Prevention of Stroke in Subjects With Atrial Fibrillation) trial. The associations between baseline hs-TnT levels and outcomes were evaluated using adjusted Cox regression models.

RESULTS

Levels of hs-TnT were measurable in 93.5% of patients; 75% had levels >7.5 ng/l, 50% had levels >11.0 ng/l, and 25% had levels >16.7 ng/l. During a median 1.9-year period, the annual rates of stroke or systemic embolism ranged from 0.87% in the lowest hs-TnT quartile to 2.13% in the highest hs-TnT quartile (adjusted hazard ratio [HR]: 1.94; 95% confidence interval [CI]: 1.35 to 2.78; p = 0.0010). The annual rates in the corresponding groups ranged from 0.46% to 4.24% (adjusted HR: 4.31; 95% CI: 2.91 to 6.37; p < 0.0001) for cardiac death and from 1.26% to 4.21% (adjusted HR: 1.91; 95% CI: 1.43 to 2.56; p = 0.0001) for major bleeding. Adding hs-TnT levels to the CHA2DS2VASc score improved the C statistic from 0.620 to 0.635 for stroke or systemic embolism (p = 0.0226), from 0.592 to 0.711 for cardiac death (p < 0.0001), and from 0.591 to 0.629 for major bleeding (p < 0.0001). Apixaban reduced rates of stroke, mortality, and bleeding regardless of the hs-TnT level.

CONCLUSIONS

Levels of hs-TnT are often elevated in patients with AF. The hs-TnT level is independently associated with an increased risk of stroke, cardiac death, and major bleeding and improves risk stratification beyond the CHA2DS2VASc risk score. The benefits of apixaban as compared with warfarin are consistent regardless of the hs-TnT level. (Apixaban for the Prevention of Stroke in Subjects With Atrial Fibrillation [ARISTOTLE]; NCT00412984).

Impaired cardiac baroreflex sensitivity predicts response to renal sympathetic denervation in patients with resistant hypertension. J Am Coll Cardiol. 2013;62:2124-2130. [PMID: 23973686 DOI: 10.1016/j.jacc.2013.07.046]

OBJECTIVES

This study sought to evaluate cardiac baroreflex sensitivity (BRS) as a predictor of response to renal sympathetic denervation (RDN).

BACKGROUND

Catheter-based RDN is a novel treatment option for patients with resistant arterial hypertension. It is assumed that RDN reduces efferent renal and central sympathetic activity.

METHODS

Fifty patients (age 60.3 ± 13.8 years [mean ± SD mean systolic blood pressure (BP) on ambulatory blood pressure monitoring (ABPM) 157 ± 22 mm Hg, despite medication with 5.4 ± 1.4 antihypertensive drugs) underwent RDN. Prior to RDN, a 30-min recording of continuous arterial BP (Finapres; TNO-TPD Biomedical Instrumentation, Amsterdam, the Netherlands) and high-resolution electrocardiography (1.6 kHz in orthogonal XYZ leads) was performed in all patients under standardized conditions. Cardiac BRS was assessed by phase-rectified signal averaging (BRSPRSA) according to previously published technologies. Response to RDN was defined as a reduction of mean systolic BP on ABPM by 10 mm Hg or more at 6 months after RDN.

RESULTS

Six months after RDN, mean systolic BP on ABPM was significantly reduced from 157 ± 22 mm Hg to 149 ± 20 mm Hg (p = 0.003). Twenty-six of the 50 patients (52%) were classified as responders. BRSPRSA was significantly lower in responders than nonresponders (0.16 ± 0.75 ms/mm Hg vs. 1.54 ± 1.73 ms/mm Hg; p < 0.001). Receiver-operator characteristics analysis revealed an area under the curve for prediction of response to RDN by BRSPRSA of 81.2% (95% confidence interval: 70.0% to 90.1%; p < 0.001). On multivariable logistic regression analysis, reduced BRSPRSA was the strongest predictor of response to RDN, which was independent of all other variables tested.

CONCLUSIONS

Impaired cardiac BRS identifies patients with resistant hypertension who respond to RDN.

Stroke prediction with an adjusted R-CHA2DS2VASc score in a cohort of patients with a Myocardial Infarction

INTRODUCTION

A new risk stratification scheme incorporating the original CHADS2 score and renal function, entitled R(2)CHADS(2), was validated in the ROCKET-AF and ATRIA study cohorts.

AIMS

Adjusting and validating a modified R-CHA2DS2VASc score as a predictor of ischaemic stroke and all-cause mortality in patients discharged following admission for a Myocardial Infarction (MI).

MATERIALS AND METHODS

Observational retrospective single-centre cohort study including 1711 patients admitted with MI and discharged alive. We tested the prognostic performance of R-CHA2DS2VASc, based on the original CHA2DS2VASc score with few modifications (addition of renal function parameters [glomerular filtration rate and urea], performance of a revascularization procedure and history of atrial fibrillation). R-CHA2DS2VASc was evaluated for its discriminative performance and calibration in the prediction of ischaemic stroke (primary endpoint), all-cause mortality and a composite endpoint of ischemic stroke plus all-cause mortality (secondary outcomes) during follow-up.

RESULTS

R-CHA2DS2VASc score's areas under the curve (AUC) for the occurrence of primary and secondary outcomes were: Ischaemic stroke: AUC 0.717 ± 0.031, p<0.001 (vs. 0.681 ± 0.043 for CHA2DS2VASc, p=0.290); all-cause mortality during follow-up: AUC 0.811 ± 0.014, p<0.001 (vs. 0.782 ± 0.019 for GRACE, p=0.245); composite endpoint: AUC 0.803 ± 0.014, p<0.001. The integrated discrimination improvement index (IDI) and relative IDI for the primary endpoint were 0.015 and 28.2%, respectively, while the IDI and relative IDI for all-cause mortality were 0.13 and 72.1%, suggesting a large improvement in risk stratification. An R-CHA2DS2VASc score below 3 had a negative predictive value of 98.6% for the occurrence of ischaemic stroke.

CONCLUSIONS

The modified R-CHA2DS2VASc score has shown good calibration and high discriminative performance in the prediction of post-discharge ischaemic stroke and all-cause mortality. The inclusion of renal function in thromboembolic risk predicting schemes seems warranted.

Early echocardiographic deformation analysis for the prediction of sudden cardiac death and life-threatening arrhythmias after myocardial infarction

OBJECTIVES

This study sought to hypothesize that global longitudinal strain (GLS) as a measure of infarct size, and mechanical dispersion (MD) as a measure of myocardial deformation heterogeneity, would be of incremental importance for the prediction of sudden cardiac death (SCD) or malignant ventricular arrhythmias (VA) after acute myocardial infarction (MI).

BACKGROUND

SCD after acute MI is a rare but potentially preventable late complication predominantly caused by malignant VA. Novel echocardiographic parameters such as GLS and MD have previously been shown to identify patients with chronic ischemic heart failure at increased risk for arrhythmic events. Risk prediction during admission for acute MI is important because a majority of SCD events occur in the early period after hospital discharge.

METHODS

We prospectively included patients with acute MI and performed echocardiography, with measurements of GLS and MD defined as the standard deviation of time to peak negative strain in all myocardial segments. The primary composite endpoint (SCD, admission with VA, or appropriate therapy from a primary prophylactic implantable cardioverter-defibrillator [ICD]) was analyzed with Cox models.

RESULTS

A total of 988 patients (mean age: 62.6 ± 12.1 years; 72% male) were included, of whom 34 (3.4%) experienced the primary composite outcome (median follow-up: 29.7 months). GLS (hazard ratio [HR]: 1.38; 95% confidence interval [CI]: 1.25 to 1.53; p < 0.0001) and MD (HR/10 ms: 1.38; 95% CI: 1.24 to 1.55; p < 0.0001) were significantly related to the primary endpoint.

GLS (HR

1.24; 95% CI: 1.10 to 1.40; p = 0.0004) and MD (HR/10 ms: 1.15; 95% CI: 1.01 to 1.31; p = 0.0320) remained independently prognostic after multivariate adjustment. Integrated diagnostic improvement (IDI) and net reclassification index (NRI) were significant for the addition of GLS (IDI: 4.4% [p < 0.05]; NRI: 29.6% [p < 0.05]), whereas MD did not improve risk reclassification when GLS was known.

CONCLUSIONS

Both GLS and MD were significantly and independently related to SCD/VA in these patients with acute MI and, in particular, GLS improved risk stratification above and beyond existing risk factors.

Anaemia to predict outcome in patients with acute coronary syndromes

BACKGROUND

Owing to the heterogeneous population of patients with acute coronary syndromes (ACS), risk stratification with tools such as the GRACE risk score is recommended to guide therapeutic management and improve outcome.

AIM

To evaluate whether anaemia refines the value of the GRACE risk model to predict midterm outcome after an ACS.

METHODS

A prospective registry of 1064 ACS patients (63 ± 14 years; 73% men; 57% ST-segment elevation myocardial infarction [MI]) was studied. Anaemia was defined as haemoglobin less than 13 mg/dL in men or less than 12 mg/dL in women. The primary endpoint was 6-month death or rehospitalization for MI.

RESULTS

The primary endpoint was reached in 132 patients, including 68 deaths. Anaemia was associated with adverse clinical outcomes (hazard ratio 3.008, 95% confidence interval 2.137-4.234; P<0.0001) in univariate analysis and remained independently associated with outcome after adjustment for the Global Registry of Acute Coronary Events (GRACE) risk score (hazard ratio 2.870, 95% confidence interval 1.815-4.538; P<0.0001). Anaemia provided additional prognostic information to the GRACE score as demonstrated by a systematic improvement in global model fit and discrimination (c-statistic increasing from 0.633 [0.571;0.696] to 0.697 [0.638;0.755]). Subsequently, adding anaemia to the GRACE score led to reclassification of 595 patients into different risk categories; 16.5% patients at low risk (≤ 5% risk of death or rehospitalization for MI) were upgraded to intermediate (>5-10%) or high risk (>10%); 79.5% patients at intermediate risk were reclassified as low (55%) or high risk (24%); and 45.5% patients at high risk were downgraded to intermediate risk. Overall, 174 patients were reclassified into a higher risk category (17.3%) and 421 into a lower risk category (41.9%).

CONCLUSION

Anaemia provides independent additional prognostic information to the GRACE score. Combining anaemia with the GRACE score refines its predictive value, which often overestimates the risk.

Modeling serum level of s100β and bispectral index to predict outcome after cardiac arrest

OBJECTIVES

This study was designed to evaluate multimodal prognostication in patients after cardiac arrest (CA).

BACKGROUND

Accurate methods to predict outcome after CA are lacking.

METHODS

Seventy-five patients with CA treated with therapeutic hypothermia after cardiac resuscitation were enrolled in this prospective observational study. Serum levels of neuron-specific enolase (NSE) and neuron-enriched S100 beta (S100β) were measured 48 h after CA. Bispectral index (BIS) was continuously monitored during the first 48 h after CA. The primary endpoint was neurological outcome, as defined by the cerebral performance category (CPC) at 6-month follow-up: scores 1 or 2 indicated good outcome, and scores 3 to 5, poor outcome. The secondary endpoint was survival.

RESULTS

A total of 46 (61%) patients survived at 6 months and 41 (55%) patients had CPC 1 or 2. Levels of NSE and S100β were higher in patients with poor outcomes compared with patients with good outcomes (4-fold and 10-fold, respectively; p < 0.001). BIS was lower in patients with poor outcomes (10-fold; p < 0.001). NSE, S100β, or BIS alone predicted neurological outcome, with areas under the receiver-operating characteristic curve (AUC) above 0.80. Combined determination of S100β and BIS had an incremental predictive value (AUC: 0.95). S100β improved discriminations based on BIS (p = 0.0008), and BIS improved discriminations based on S100β (p < 10(-5)). Patients with S100β level above 0.03 μg/l and BIS below 5.5 had a 3.6-fold higher risk of poor neurological outcome (p < 0.0001). S100β and BIS predicted 6-month mortality (log-rank statistic: 50.41; p < 0.001).

CONCLUSIONS

Combined determination of serum level of S100β and BIS monitoring accurately predicts outcome after CA.

Aggregate risk score based on markers of inflammation, cell stress, and coagulation is an independent predictor of adverse cardiovascular outcomes

OBJECTIVES

This study sought to determine an aggregate, pathway-specific risk score for enhanced prediction of death and myocardial infarction (MI).

BACKGROUND

Activation of inflammatory, coagulation, and cellular stress pathways contribute to atherosclerotic plaque rupture. We hypothesized that an aggregate risk score comprised of biomarkers involved in these different pathways-high-sensitivity C-reactive protein (CRP), fibrin degradation products (FDP), and heat shock protein 70 (HSP70) levels-would be a powerful predictor of death and MI.

METHODS

Serum levels of CRP, FDP, and HSP70 were measured in 3,415 consecutive patients with suspected or confirmed coronary artery disease (CAD) undergoing cardiac catheterization. Survival analyses were performed with models adjusted for established risk factors.

RESULTS

Median follow-up was 2.3 years. Hazard ratios (HRs) for all-cause death and MI based on cutpoints were as follows: CRP ≥3.0 mg/l, HR: 1.61; HSP70 >0.625 ng/ml, HR; 2.26; and FDP ≥1.0 μg/ml, HR: 1.62 (p < 0.0001 for all). An aggregate biomarker score between 0 and 3 was calculated based on these cutpoints. Compared with the group with a 0 score, HRs for all-cause death and MI were 1.83, 3.46, and 4.99 for those with scores of 1, 2, and 3, respectively (p for each: <0.001). Annual event rates were 16.3% for the 4.2% of patients with a score of 3 compared with 2.4% in 36.4% of patients with a score of 0. The C statistic and net reclassification improved (p < 0.0001) with the addition of the biomarker score.

CONCLUSIONS

An aggregate score based on serum levels of CRP, FDP, and HSP70 is a predictor of future risk of death and MI in patients with suspected or known CAD.

Significance of high-sensitivity cardiac troponin T in hypertrophic cardiomyopathy

OBJECTIVES

This study investigated the significance of the serum high-sensitivity cardiac troponin T (hs-cTnT) marker for prediction of adverse events in hypertrophic cardiomyopathy (HCM).

BACKGROUND

Although serum cardiac troponins as sensitive and specific markers of myocardial injury have become well-established diagnostic and prognostic markers in acute coronary syndrome, the usefulness of hs-cTnT for prediction of cardiovascular events in patients with HCM is unclear.

METHODS

We performed clinical evaluation, including measurements of hs-cTnT in 183 consecutive patients with HCM.

RESULTS

Of 183 HCM patients, 99 (54%) showed abnormal hs-cTnT values (>0.014 ng/ml). During a mean follow-up of 4.1 ± 2.0 years, 32 (32%) of the 99 patients in the abnormal hs-cTnT group, but only 6 (7%) of 84 patients with normal hs-cTnT values, experienced cardiovascular events: cardiovascular deaths, unplanned heart failure admissions, sustained ventricular tachycardia, embolic events, and progression to New York Heart Association functional class III or IV status (hazard ratio [HR]: 5.05, p < 0.001). Abnormal hs-cTnT value remained an independent predictor of these cardiovascular events after multivariate analysis (HR: 3.23, p = 0.012). Furthermore, in the abnormal hs-cTnT group, overall risk increased with an increase in hs-cTnT value (HR: 1.89/hs-cTnT 1 SD increase in the logarithmic scale, 95% confidence interval: 1.13 to 3.15; p = 0.015 [SD: 0.59]).

CONCLUSIONS

In patients with HCM, an abnormal serum concentration of hs-cTnT is an independent predictor of adverse outcome, and a higher degree of abnormality in hs-cTnT value is associated with a greater risk of cardiovascular events.

Using a clinic based creativity initiative to reduce HIV related stigma at the Infectious Diseases Institute, Mulago National Referral Hospital, Uganda

BACKGROUND

Stigma has been associated with chronic health conditions such as HIV/AIDS, leprosy, tuberculosis, Mental illness and Epilepsy. Different forms of stigma have been identified: enacted stigma, perceived stigma, and self stigma. Stigma is increasingly regarded as a key driver of the HIV/AIDS epidemic and has a major impact on public health interventions.

OBJECTIVES

The initiative was to provide activities in the clinic while patients waited to be seen by healthcare professionals. It was envisaged this would contribute to reduction of clinic based stigma felt by clients.

METHODS

This was a repeated cross-sectional survey (October-November 2005 and March-April 2007) that was conducted at the Infectious Diseases Institute clinic (IDC) at Mulago, the national referral hospital in Uganda. We utilized quantitative (survey) and qualitative (key informants, focus group discussions) methods to collect the data. Data were collected on stigma before the creativity initiative intervention was implemented, and a second phase survey was conducted to assess effectiveness of the interventions.

RESULTS

Clients who attended the IDC before the creativity intervention were about twice as likely to fear catching an infection as those who came after the intervention. The proportion that had fears to be seen by a friend or relative at the clinic decreased. Thus during the implementation of the Creativity intervention, HIV related stigma was reduced in this clinic setting.

CONCLUSIONS

The creativity intervention helped to build self esteem and improved communication among those attending the clinic; there was observed ambiance at the clinic and clients became empowered, with creative, communication and networking skills. Improved knowledge and communication are key in addressing self stigma among HIV positive individuals.

Anthropometric indices added the predictive ability of iron status in prognosis of atherosclerosis

BACKGROUND

Abnormal homeostasis of iron such as deficiency or overload is associated with the pathogenesis of cardiovascular disease (CVD). Another risk factor for CVD is obesity whose added predictive ability to iron status has been assessed by few study. This study aimed to eva¬luate the effect of adding anthropometric indices to a model based on iron status as risk factors of CVD.

METHODS

This cross-sectional study included 140 adult women aged 18-50 years randomly se-lected from Sheikhorrais Clinic that is one of the Tabriz University sub-specialized clinics in 2011. Anthropometric indices, carotid intima-media thickness (CIMT) and body iron status were measured by standard protocol, non-invasive ultrasound and concentrations of serum iron, ferri¬tin, TIBC (Total iron Binding Capacity) and complete blood cell counts (CBC), respectively. In¬tegrated discriminatory improvement index (IDI) and net reclassification improvement index (NRI) were used as the measures of added predictive ability of anthropometric measures to the iron statues.

RESULTS

IDI (SE) after adding Waist Circumference (WC), Waist to Heap Ratio (WHR), Waist to Height Ratio (WHtR), Body Mass Index (BMI) and Body fat (%) to base model was 0.12 (0.028), 0.09 (0.026), 0.12 (0.028), 0.07 (0.022) and 0.10 (0.026) respectively. The NRI (SE) was 0.10 (0.065) for WC, 0.03 (0.058) for WHR, 0.07 (0.067) for WHtR, 0.05 (0.067) for BMI, and 0.08 (0.064) for Body fat.

CONCLUSIONS

Anthropometric indices could significantly add to the predictive ability of the iron statues, with highest IDI when WC and WHtR were added to the base model. It suggests that by adding WC and WHtR to the iron status lead us to a more optimal model for predicting the ini¬tial stage of atherosclerosis.

Inhibition Studies on Enzymes Involved in Isoprenoid Biosynthesis: Focus on Two Potential Drug Targets: DXR and IDI-2 Enzymes

Isoprenoid compounds constitute an immensely diverse group of acyclic, monocyclic and polycyclic compounds that play important roles in all living organisms. Despite the diversity of their structures, this plethora of natural products arises from only two 5-carbon precursors, isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). This review will discuss the enzymes in the mevalonate (MVA) and methylerythritol phosphate (MEP) biosynthetic pathways leading to IPP and DMAPP with a particular focus on MEP synthase (DXR) and IPP isomerase (IDI), which are potential targets for the development of antibiotic compounds. DXR is the second enzyme in the MEP pathway and the only one for which inhibitors with antimicrobial activity at pharmaceutically relevant concentrations are known. All of the published DXR inhibitors are fosmidomycin analogues, except for a few bisphosphonates with moderate inhibitory activity. These far, there are no other candidates that target DXR. IDI was first identified and characterised over 40 years ago (IDI-1) and a second convergently evolved isoform (IDI-2) was discovered in 2001. IDI-1 is a metalloprotein found in Eukarya and many species of Bacteria. Its mechanism has been extensively studied. In contrast, IDI-2 requires reduced flavin mononucleotide as a cofactor. The mechanism of action for IDI-2 is less well defined. This review will describe how lead inhibitors are being improved by structure-based drug design and enzymatic assays against DXR to lead to new drug families and how mechanistic probes are being used to address questions about the mechanisms of the isomerases.