Bone Density in Children with Single Ventricle Physiology

Background Children with chronic diseases are at risk for low bone mineral density (BMD). There are no studies of BMD in children with congenital heart disease and particularly SV. Children with this defect are often treated with warfarin, suspected to negatively impact BMD in adults. We assessed BMD in patients with single ventricle (SV) physiology and compared the BMD of subjects taking warfarin to those who were not. Methods Subjects 5-12 years with SV were included. BMD z-scores by dual-energy X-ray absorptiometry (DXA) of the spine and total body less head (TBLH) were obtained. Calcium intake, activity level, height, and Tanner stage were assessed. Linear regression models and t-tests were used to investigate differences between participants and normative data as well as between subjects' subgroups. Results Twenty six subjects were included; 16 took warfarin. Mean BMD z-score at the spine was significantly lower than expected at -1.0±0.2 (p<0.0001), as was the BMD z-score for TBLH at - 0.8±0.2 (p<0.0001). Those results remained significant after adjusting for height. Subjects who were on warfarin tended to have lower BMD at both the spine and TBLH than those who were not, with a z-score difference of 0.6±0.46 at the spine (p=0.106) and a difference of 0.4±0.34 at TBLH (p=0.132). Conclusions BMD is significantly reduced in children with SV. Warfarin appears to lower BMD but the effect is less conclusive. Continued evaluation is recommended for these patients at risk for reduced bone density. Evaluation of other cardiac patients on warfarin therapy should also be considered

Predicting the glomerular filtration rate in bariatric surgery patients

BACKGROUND/AIMS: Identifying the best method to estimate the glomerular filtration rate (GFR) in bariatric surgery patients has important implications for the clinical care of obese patients and research into the impact of obesity and weight reduction on kidney health. We therefore performed such an analysis in patients before and after surgical weight loss. METHODS: Fasting measured GFR (mGFR) by plasma iohexol clearance before and after bariatric surgery was obtained in 36 severely obese individuals. Estimated GFR was calculated using the Modification of Diet in Renal Disease equation, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation using serum creatinine only, the CKD-EPI equation using serum cystatin C only and a recently derived equation that uses both serum creatinine and cystatin C (CKD-EPIcreat-cystC) and then compared to mGFR. RESULTS: Participants were primarily middle-aged white females with a mean baseline body mass index of 46 ± 9, serum creatinine of 0.81 ± 0.24 mg/dl and mGFR of 117 ± 40 ml/min. mGFR had a stronger linear relationship with inverse cystatin C before (r = 0.28, p = 0.09) and after (r = 0.38, p = 0.02) surgery compared to the inverse of creatinine (before: r = 0.26, p = 0.13; after: r = 0.11, p = 0.51). mGFR fell by 17 ± 35 ml/min (p = 0.007) following surgery. The CKD-EPIcreat-cystC was unquestionably the best overall performing estimating equation before and after surgery, revealing very little bias and a capacity to estimate mGFR within 30% of its true value over 80% of the time. This was true whether or not mGFR was indexed for body surface area. CONCLUSIONS: In severely obese bariatric surgery patients with normal kidney function, cystatin C is more strongly associated with mGFR than is serum creatinine. The CKD-EPIcreat-cystC equation best predicted mGFR both before and after surgery

Use of Functional Linear Models to Detect Associations between Characteristics of Walking and Continuous Responses Using Accelerometry Data

Various methods exist to measure physical activity. Subjective methods, such as diaries and surveys, are relatively inexpensive ways of measuring one&rsquo;s physical activity; however, they are prone to measurement error and bias due to self-reporting. Wearable accelerometers offer a non-invasive and objective measure of one&rsquo;s physical activity and are now widely used in observational studies. Accelerometers record high frequency data and each produce an unlabeled time series at the sub-second level. An important activity to identify from the data collected is walking, since it is often the only form of activity for certain populations. Currently, most methods use an activity summary which ignores the nuances of walking data. We propose methodology to model specific continuous responses with a functional linear model utilizing spectra obtained from the local fast Fourier transform (FFT) of walking as a predictor. Utilizing prior knowledge of the mechanics of walking, we incorporate this as additional information for the structure of our transformed walking spectra. The methods were applied to the in-the-laboratory data obtained from the Developmental Epidemiologic Cohort Study (DECOS)

Using Simulation to Assess the Influence of Race and Insurer on Shared Decision-making in Periviable Counseling

Introduction: Sociodemographic differences have been observed in the treatment of extremely premature (periviable) neonates, but the source of this variation is not well understood. We assessed the feasibility of using simulation to test the effect of maternal race and insurance status on shared decision making (SDM) in periviable counseling. Methods: We conducted a 2 × 2 factorial simulation experiment in which obstetricians and neonatologists counseled 2 consecutive standardized patients diagnosed with ruptured membranes at 23 weeks, counterbalancing race (black/white) and insurance status using random permutation. We assessed verisimilitude of the simulation in semistructured debriefing interviews. We coded physician communication related to resuscitation, mode of delivery, and steroid decisions using a 9-point SDM coding framework and then compared communication scores by standardized patient race and insurer using analysis of variance. Results: Sixteen obstetricians and 15 neonatologists participated; 71% were women, 84% were married, and 75% were parents; 91% of the physicians rated the simulation as highly realistic. Overall, SDM scores were relatively high, with means ranging from 6.4 to 7.9 (of 9). There was a statistically significant interaction between race and insurer for SDM related to steroid use and mode of delivery (P < 0.01 and P = 0.01, respectively). Between-group comparison revealed nonsignificant differences (P = <0.10) between the SDM scores for privately insured black patients versus privately insured white patients, Medicaid-insured white patients versus Medicaid-insured black patients, and privately insured black patients versus Medicaid-insured black patients. Conclusions: This study confirms that simulation is a feasible method for studying sociodemographic effects on periviable counseling. Shared decision making may occur differentially based on patients’ sociodemographic characteristics and deserves further study

Effectiveness of implementing a wake up and breathe program on sedation and delirium in the ICU

OBJECTIVES: Mechanically ventilated critically ill patients receive significant amounts of sedatives and analgesics that increase their risk of developing coma and delirium. We evaluated the impact of a "Wake-up and Breathe Protocol" at our local ICU on sedation and delirium. DESIGN: A pre/post implementation study design. SETTING: A 22-bed mixed surgical and medical ICU. PATIENTS: Seven hundred two consecutive mechanically ventilated ICU patients from June 2010 to January 2013. INTERVENTIONS: Implementation of daily paired spontaneous awakening trials (daily sedation vacation plus spontaneous breathing trials) as a quality improvement project. MEASUREMENTS AND MAIN RESULTS: After implementation of our program, there was an increase in the mean Richmond Agitation Sedation Scale scores on weekdays of 0.88 (p < 0.0001) and an increase in the mean Richmond Agitation Sedation Scale scores on weekends of 1.21 (p < 0.0001). After adjusting for age, race, gender, severity of illness, primary diagnosis, and ICU, the incidence and prevalence of delirium did not change post implementation of the protocol (incidence: 23% pre vs 19.6% post; p = 0.40; prevalence: 66.7% pre vs 55.3% post; p = 0.06). The combined prevalence of delirium/coma decreased from 90.8% pre protocol implementation to 85% postimplementation (odds ratio, 0.505; 95% CI, 0.299-0.853; p = 0.01). CONCLUSIONS: Implementing a "Wake Up and Breathe Program" resulted in reduced sedation among critically ill mechanically ventilated patients but did not change the incidence or prevalence of delirium

Differentiating Between Walking and Stair Climbing Using Raw Accelerometry Data

Wearable accelerometers provide an objective measure of human physical activity. They record high frequency unlabeled three-dimensional time series data. We extract meaningful features from the raw accelerometry data and based on them develop and evaluate a classification method for the detection of walking and its sub-classes, i.e. level walking, descending stairs and ascending stairs. Our methodology is tested on a sample of 32 middle-aged subjects for whom we extracted features based on the Fourier and wavelet transforms. We build subject-specific and group-level classification models utilizing a tree-based methodology. We evaluate the effects of sensor location and tuning parameters on the classification accuracy of the tree models. In the group-level classification setting, we propose a robust feature inter-subject normalization and evaluate its performance compared to unnormalized data. The overall classification accuracy for the three activities at the subject-specific level was on average 87.6%, with the ankle-worn accelerometers showing the best performance with an average accuracy 90.5%. At the group-level, the average overall classification accuracy for the three activities using the normalized features was 80.2% compared to 72.3% for the unnormalized features. In summary, a framework is provided for better use and feature extraction from raw accelerometry data to differentiate among different walking modalities as well as considerations for study design

Population Point Prevalence of SARS-CoV-2 Infection Based on a Statewide Random Sample — Indiana, April 25–29, 2020

During April 25–29, 2020, Indiana conducted statewide random sample testing of persons aged ≥12 years to assess prevalence of active infection and presence of antibodies to SARS-CoV-2; additional nonrandom sampling was conducted in racial and ethnic minority communities to better understand the impact of the virus in certain racial and ethnic minority populations.Nir Menachemi reports a grant from State of Indiana which funded this study. Virginia Caine reports that she is a member of the MMWR Editorial Board. Brian E. Dixon and William F. Fadel report grants from the Indiana State Department of Health. Paul K. Halverson reports a grant from the State of Indiana. No other potential conflicts of interest were disclosed

Symptoms and symptom clusters associated with SARS-CoV-2 infection in community-based populations: Results from a statewide epidemiological study

Background: Prior studies examining symptoms of COVID-19 are primarily descriptive and measured among hospitalized individuals. Understanding symptoms of SARS-CoV-2 infection in pre-clinical, community-based populations may improve clinical screening, particularly during flu season. We sought to identify key symptoms and symptom combinations in a community-based population using robust methods. Methods: We pooled community-based cohorts of individuals aged 12 and older screened for SARS-CoV-2 infection in April and June 2020 for a statewide seroprevalence study. Main outcome was SARS-CoV-2 positivity. We calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for individual symptoms as well as symptom combinations. We further employed multivariable logistic regression and exploratory factor analysis (EFA) to examine symptoms and combinations associated with SARS-CoV-2 infection. Results: Among 8214 individuals screened, 368 individuals (4.5%) were RT-PCR positive for SARS-CoV-2. Although two-thirds of symptoms were highly specific (>90.0%), most symptoms individually possessed a PPV <50.0%. The individual symptoms most greatly associated with SARS-CoV-2 positivity were fever (OR=5.34, p<0.001), anosmia (OR=4.08, p<0.001), ageusia (OR=2.38, p=0.006), and cough (OR=2.86, p<0.001). Results from EFA identified two primary symptom clusters most associated with SARS-CoV-2 infection: (1) ageusia, anosmia, and fever; and (2) shortness of breath, cough, and chest pain. Moreover, being non-white (13.6% vs. 2.3%, p<0.001), Hispanic (27.9% vs. 2.5%, p<0.001), or living in an Urban area (5.4% vs. 3.8%, p<0.001) was associated with infection. Conclusions: Symptoms can help distinguish SARS-CoV-2 infection from other respiratory viruses, especially in community or urgent care settings where rapid testing may be limited. Symptoms should further be structured in clinical documentation to support identification of new cases and mitigation of disease spread by public health. These symptoms, derived from asymptomatic as well as mildly infected individuals, can also inform vaccine and therapeutic clinical trials.This work was supported by a grant from the State of Indiana to the IU Fairbanks School of Public Health to conduct seroprevalence testing in the state population. Dr. Dixon receives funding from the U.S. National Library of Medicine (T15LM012502) as well as the U.S. Centers for Disease Control and Prevention (U18DP006500) and the Indiana State Department of Health to support disease surveillance research. The funder had no role in study design, data collection, data analysis, data interpretation, or writing of the paper

Mobility Impairment in Patients New to Dialysis

Background: Impaired mobility is associated with functional dependence, frailty, and mortality in prevalent patients undergoing dialysis. We investigated risk factors for mobility impairment, (poor gait speed) in patients incident to dialysis, and changes in gait speed over time in a 2-year longitudinal study. Methods: One hundred eighty-three patients enrolled within 6 months of dialysis initiation were followed up 6, 12, and 24 months later. Grip strength, health-related quality of life, and comorbidities were assessed at baseline. Outcomes were (a) baseline gait speed and (b) change in gait speed over time. Gait speed was assessed by 4-meter walk. Multivariate linear regression was used to identify risk factors for low gait speed at baseline. For longitudinal analyses, linear mixed effects modeling with gait speed modeled over time was used as the outcome. Results: Participants were 54.7 ± 12.8 years old, 52.5% men, 73.9% black with mean dialysis vintage of 100.1 ± 46.9 days and median gait speed 0.78 (0.64-0.094) m/s. Lower health utility and grip strength, diabetic nephropathy, and walking aids were associated with lower baseline gait speed. Loss of 0.1 m/s gait speed occurred in 24% of subjects at 1 year. In multivariate mixed effects models, only age, walking aid use, lower health utility, and lower handgrip strength were significantly associated with gait speed loss. Conclusions: In our cohort of incident dialysis patients, overall gait speed is very low and 54.2% of the subjects continue to lose gait speed over 2 years. Older age, lower handgrip strength, and quality of life are risk factors for slowness. Patients at highest risk of poor gait speed can be identified at dialysis initiation to allow targeted implementation of therapeutic options

Intention to treat: obstetrical management at the threshold of viability

Background Despite medical advances in the care of extremely preterm neonates and growing acceptance of resuscitation at 23 and even 22 weeks gestation, controversy remains concerning the use of antepartum obstetric intervention s that are intended to improve outcomes in the setting of anticipated extremely preterm birth. In the absence of demonstrated benefit at <23 weeks gestation and with uncertain benefit at 23 weeks gestation, previous obstetric committee opinions have advised against their use at these gestational ages. Objective The purpose of this study was to review the use of obstetric intervention s at the threshold of viability based on neonatal resuscitation plan and to review the odds of survival to neonatal intensive care unit discharge based on use of obstetric intervention s with adjustment for neonatal factors. Study Design This retrospective study of 6 study centers reviewed pregnant patients who were admitted between 22+0/7 and 24+6/7 weeks gestation facing delivery from 2011–2015. Patients with known anomalies or missing data were excluded. Records were reviewed for demographics, resuscitation plan, and obstetric intervention s. Mode of delivery, delivery room care, and final infant dispositions were recorded. Multiple gestations were included as 1 pregnancy in regard to the use of obstetric intervention s and were excluded from survival analysis. Results Four hundred seventy-eight mothers met the inclusion criteria. When resuscitation was planned, mothers were more likely to receive all conventional obstetric intervention s (antenatal steroids, magnesium sulfate for neuroprotection, tocolytics, and Group Beta Streptococcus prophylaxis), regardless of gestational age at admission, and were more likely to be delivered by cesarean section (P<.05). Analyzed as a group, when antenatal steroids, magnesium sulfate, tocolytics and Group Beta Streptococcus prophylaxis were administered, the odds of survival to neonatal intensive care unit discharge increased for newborn infants who were born at 22 (odds ratio, 11.33; 95% confidence interval, 1.405–91.4) and 23 weeks gestation (odds ratio, 15.5; 95% confidence interval, 3.747-64.11; P<.05). In singletons, the odds of survival to neonatal intensive care unit discharge was not improved by cesarean delivery vs vaginal delivery, even after adjustment for the use of additional interventions, weight, gender, and gestational age (odds ratio, 1.0; 95% confidence interval, 0.59–1.8; P=.912). Conclusion In this study, when postnatal resuscitation was planned at 22 and 23 weeks gestation, women were more likely to receive antenatal steroids, magnesium sulfate, and antibiotics; provision of this bundle imparted survival benefit at 23 weeks gestation but could not be demonstrated at 22 weeks gestation because of the small sample size. These findings support of neonate-oriented obstetric interventions in the setting of delivery at 23 weeks gestation when resuscitation is planned and further exploration of optimal obstetric care when resuscitation of infants who were born at 22 weeks gestation is anticipated