Carly E. Milliren

Survival Benefit From Transplantation in Patients Listed for Heart Transplantation in the United States

OBJECTIVES The aim of this study was to assess the survival benefit from heart transplantation (HT), defined as reduction in the risks for 90-day and 1-year mortality on undergoing HT close to listing, in candidates stratified by their risk for waiting list mortality. BACKGROUND Among patients listed for HT, those at higher risk for death without transplantation are also at higher risk for early post-transplantation mortality. METHODS All patients age ≥18 years listed for HT in the United States from 2007 to 2010 were analyzed. A model was developed to predict the risk for waiting list mortality within 90 days, and listed patients were stratified into 10 risk groups (deciles). All groups were followed for 1 year to assess cumulative 1-year mortality while on the waiting list. Models of 90-day and 1-year post-transplantation mortality were developed using recipient data, and these risks were estimated at listing in all listed candidates. RESULTS Of 10,159 patients listed for HT, 596 (5.9%) died within 90 days and 1,054 (10.4%) within 1 year without undergoing transplantation. Of 5,720 recipients of transplants with 1-year follow-up, 576 (10.1%) died within 1 year. The risk for death while on the waiting list within 90 days increased from 1.6% to 19% across the 10 risk groups. The survival benefit from HT increased progressively with higher risk for death without transplantation (p < 0.001 for trend), but there was no benefit in the first 6 risk groups. CONCLUSIONS The risk for waiting list mortality varies considerably among HT candidates. Although the survival benefit of HT generally increases with increasing risk for waiting list mortality, there is no measurable benefit in many candidates at the lower end of the risk spectrum.

Helpful or harmful? Prospective association between weight misperception and weight gain among overweight and obese adolescents and young adults

Background/Objective:Weight misperception is common among adolescents with obesity, but it is not known whether weight perception is related to future weight gain. The objective of the study was to examine the prospective association between accurate weight perception versus weight misperception and weight change among youth who are overweight or obese.Subjects/Methods:Using a subsample of The National Longitudinal Study of Adolescent to Adult Health Wave II cohort, we used linear regression modeling (adjusted for age, baseline body mass index (BMI), parental education, household percent federal poverty level, depression, race and ethnicity) to examine the prospective association between weight misperception (that is, perceiving oneself to be under or normal weight) among 2738 overweight and obese youth and subsequent BMI change from Wave II (1996) to Wave IV (2008–2009). Mean age at baseline (Wave II) was 15.9 (0.1).Results:Fifty-seven percent of males and 80% of females accurately perceived themselves as overweight. In fully adjusted models, weight misperception was associated with less BMI gain among youth who were overweight and obese. Specifically, youth who perceived themselves to be at a healthy weight had lower BMI gains (males: β= −1.43, 95% confidence interval (CI)=(−2.26, −0.60), P=0.001; females: β= −1.35, 95% CI=(−2.59, −0.11), P=0.035) from Wave II to IV relative to those who accurately perceived themselves as overweight or obese.Conclusions:Contrary to commonly held assumptions, weight misperception among a non-clinical sample of youth who were overweight or obese predicted lower future weight gain. Efficacy of efforts to correct weight misperception should be rigorously examined to assess for both intended and unintended consequences.

Effect of inhaled iloprost on the exercise function of Fontan patients: A demonstration of concept

BACKGROUND Exercise capacity following Fontan surgery is often depressed. An inability to reduce pulmonary vascular resistance appropriately during exercise may contribute to this phenomenon. The aim of this study was to determine whether administration of iloprost, a selective pulmonary vasodilator, would improve exercise function after Fontan procedure. METHODS Double-blind, randomized, placebo controlled, crossover trial. Patients performed two cardiopulmonary exercise tests (CPX) separated by <1 month. A single nebulizer treatment (iloprost or placebo) was administered before each CPX. RESULTS 18 patients aged 12-49 (median 17) years were recruited. Mild throat discomfort developed in 10/18 patients during iloprost administration; all but 1 were able to complete treatment. No symptoms developed during placebo treatments (p<0.001). Two additional patients did not complete CPX: one with atrial flutter; another with developmental issues that precluded adequate CPX. In the 15 remaining subjects oxygen pulse (a surrogate for forward stroke volume) at peak exercise was higher following iloprost (median increase 1.2 ml/beat; p<0.001). Peak VO2 also rose (median increase 1.3 ml/kg/min; p<0.04). Nine patients had peak VO2 <30 ml/kg/min; each of these patients had higher peak VO2 following iloprost. Only 3/6 patients with peak VO2 >30 ml/kg/min had higher peak VO2 following iloprost (p<0.04). CONCLUSIONS Iloprost improves the peak oxygen pulse and peak VO2 of patients with Fontan physiology and appears to be particularly beneficial among patients with impaired exercise function. Treatment is associated with minor side effects. These findings support the concept of pulmonary vasodilator therapy in Fontan patients with limited functional capacity.

Using Cross-Classified Multilevel Models to Disentangle School and Neighborhood Effects: An Example Focusing on Smoking Behaviors among Adolescents in the United States

BACKGROUND Despite much interest in understanding the influence of contexts on health, most research has focused on one context at a time, ignoring the reality that individuals have simultaneous memberships in multiple settings. METHOD Using the example of smoking behavior among adolescents in the National Longitudinal Study of Adolescent Health, we applied cross-classified multilevel modeling (CCMM) to examine fixed and random effects for schools and neighborhoods. We compared the CCMM results with those obtained from a traditional multilevel model (MLM) focused on either the school and neighborhood separately. RESULTS In the MLMs, 5.2% of the variation in smoking was due to differences between neighborhoods (when schools were ignored) and 6.3% of the variation in smoking was due to differences between schools (when neighborhoods were ignored). However in the CCMM examining neighborhood and school variation simultaneously, the neighborhood-level variation was reduced to 0.4%. CONCLUSION Results suggest that using MLM, instead of CCMM, could lead to overestimating the importance of certain contexts and could ultimately lead to targeting interventions or policies to the wrong settings.

Compromised Bone Microarchitecture and Estimated Bone Strength in Young Adults With Cystic Fibrosis

CONTEXT Young adults with cystic fibrosis (CF) are at risk for low bone density and fractures, but the underlying alterations in bone microarchitecture that may contribute to their increased fracture risk are currently unknown. OBJECTIVE The main goal of this study was to use high-resolution peripheral quantitative computed tomography (HR-pQCT) to characterize the bone microarchitecture, volumetric bone mineral density (vBMD), and estimated strength of the radius and tibia in young adults with CF compared with healthy volunteers. DESIGN AND SETTING This was a cross-sectional study at an outpatient clinical research center within a tertiary academic medical center. PARTICIPANTS Thirty young adults with CF, 18 to 40 years of age, were evaluated and compared with 60 healthy volunteers matched by age (±2 years), gender, and race. MAIN OUTCOME MEASURES The primary outcomes were HR-pQCT-derived cortical and trabecular vBMD, bone microarchitecture, and estimates of bone strength. RESULTS At the radius and tibia, young adults with CF had smaller bone cross-sectional area and lower vBMD. Cortical and trabecular microarchitecture were compromised at both sites, most notably involving the trabecular bone of the tibia. These differences translated into lower estimated bone strength both at the radius and tibia. After accounting for body mass index differences, young adults with CF had lower bone area and estimated bone strength at the radius and had compromised trabecular microarchitecture and lower total and trabecular vBMD and estimated bone strength at the tibia. Alterations in trabecular bone density and microarchitecture and estimated strength measures of the tibia were also greater than expected based on dual-energy x-ray absorptiometry-derived areal BMD differences. CONCLUSIONS Young adults with CF have compromised bone microarchitecture and lower estimated bone strength at both the radius and tibia, even after accounting for their smaller body size. These skeletal deficits likely explain the higher fracture risk observed in young adults with CF.

Disentangling the relative influence of schools and neighborhoods on adolescents’ risk for depressive symptoms

OBJECTIVES Although schools and neighborhoods influence health, little is known about their relative importance, or the influence of one context after the influence of the other has been taken into account. We simultaneously examined the influence of each setting on depression among adolescents. METHODS Analyzing data from wave 1 (1994-1995) of the National Longitudinal Study of Adolescent Health, we used cross-classified multilevel modeling to examine between-level variation and individual-, school-, and neighborhood-level predictors of adolescent depressive symptoms. Also, we compared the results of our cross-classified multilevel models (CCMMs) with those of a multilevel model wherein either school or neighborhood was excluded. RESULTS In CCMMs, the school-level random effect was significant and more than 3 times the neighborhood-level random effect, even after individual-level characteristics had been taken into account. Individual-level indicators (e.g., race/ethnicity, socioeconomic status) were associated with depressive symptoms, but there was no association with either school- or neighborhood-level fixed effects. The between-level variance in depressive symptoms was driven largely by schools as opposed to neighborhoods. CONCLUSIONS Schools appear to be more salient than neighborhoods in explaining variation in depressive symptoms. Future work incorporating cross-classified multilevel modeling is needed to understand the relative effects of schools and neighborhoods.

Sexual Orientation Disparities in BMI among US Adolescents and Young Adults in Three Race/Ethnicity Groups

Obesity is a key public health issue for US youth. Previous research with primarily white samples of youth has indicated that sexual minority females have higher body mass index (BMI) and sexual minority males have lower BMI than their same-gender heterosexual counterparts, with sexual orientation differences in males increasing across adolescence. This research explored whether gender and sexual orientation differences in BMI exist in nonwhite racial/ethnic groups. Using data from Waves I–IV (1995–2009) of the US National Longitudinal Study of Adolescent Health (N = 13,306, ages 11–34 years), we examined associations between sexual orientation and BMI (kg/m2) over time, using longitudinal linear regression models, stratified by gender and race/ethnicity. Data were analyzed in 2013. Among males, heterosexual individuals showed greater one-year BMI gains than gay males across all race/ethnicity groups. Among females, white and Latina bisexual individuals had higher BMI than same-race/ethnicity heterosexual individuals regardless of age; there were no sexual orientation differences in black/African Americans. Sexual orientation disparities in BMI are a public health concern across race/ethnicity groups. Interventions addressing unhealthy weight gain in youth must be relevant for all sexual orientations and race/ethnicities.

Weight misperception among young adults with overweight/obesity associated with disordered eating behaviors.

OBJECTIVE The purpose of this study was to examine the cross-sectional association between weight misperception among young adults with overweight/obesity and disordered eating behaviors. METHOD In a subsample of young adults with overweight or obesity participating in Wave III (2001-2002) of The National Longitudinal Study of Adolescent to Adult Health (n = 5,184), we examined the cross-sectional association between weight under-perception (i.e., perceiving oneself to be at a healthy body weight or underweight) and disordered eating (fasting/meal skipping for weight control, purging/pills for weight control, overeating/loss of control eating, and use of performance-enhancing products/substances). RESULTS About 20% of young adult females under-perceived their weight compared to 48% of males. Individuals who misperceived their weight as healthy were significantly less likely to report fasting/meal skipping (Females: OR: 0.25, 95% CI: 0.14-0.43; Males: OR: 0.31, 95% CI: 0.20-0.48) and vomiting or taking diet pills/laxatives/diuretics (Females: OR: 0.10, 95% CI: 0.04-0.25; Males: OR: 0.10, 95% CI: 0.04-0.25) for weight control. Among females, those who misperceived their weight status as healthy were also less likely to report overeating or loss of control eating (OR: 0.41, 95% CI: 0.24-0.71). Greater use of performance-enhancing products/substances was seen among males who under-perceived their weight as healthy (OR: 2.06, 95% CI: 1.57-2.72) and among both females (OR: 2.29, 95% CI: 1.40-20.0) and males (OR: 2.27, 95% CI: 1.13-4.55) who perceived themselves to be underweight. DISCUSSION Weight under-perception among young adults with overweight/obesity may convey some benefit related to disordered eating behaviors, but could be a risk factor for the use of performance-enhancing products/substances.

Depression Screening in Adolescents in the United States: A National Study of Ambulatory Office-Based Practice

OBJECTIVE To determine the frequency of depression screening during ambulatory, office-based visits for adolescents seen in general/family medicine or pediatric practices in the United States using nationally representative data; to determine the patient-, provider-, and visit-level factors associated with depression screening during ambulatory visits to inform recommendations to promote screening. METHODS This cross-sectional study used the 2005-2010 National Ambulatory Medical Care and National Hospital Ambulatory Medical Care Surveys. Data were limited to ambulatory, office-based visits to general/family medicine or pediatrics clinics for adolescents aged 12 to 18 years who did not have a documented diagnosis of depression. RESULTS Depression screening was rare (0.2%; 95% confidence interval [CI] 0.1-0.3), and it was 80% less likely to occur during visits for Hispanic compared to non-Hispanic white adolescents (adjusted odds ratio [aOR] 0.2, 95% CI 0.1-0.7). Depression screening was 9.1 times more likely in the Northeast compared to the West (aOR 9.1, 95% CI 2.2-38.1) if there were no visits within past 12 months compared to 6 or more visits (aOR 6.1; 95% CI 1.8-20.4), and if stress management (aOR 24.2, 95% CI 11.8-49.5) or other mental health counseling (aOR 5.2, 95% CI 1.2-23.6) were provided. CONCLUSIONS Depression screening for adolescents is rare and is associated with racial/ethnic and regional disparities. The integration of behavioral and mental health services within the patient-centered medical home might assist providers in identifying and treating depression and in addressing such disparities.

Quantifying the Burden of Interhospital Cost Variation in Pediatric Surgery: Implications for the Prioritization of Comparative Effectiveness Research

Importance Practice variation is believed to be a driver of excess health care spending, although few objective data exist to guide the prioritization of comparative effectiveness research (CER) in pediatric surgery. Objective To identify high-priority general pediatric surgical procedures for CER on the basis of the following 2 complementary measures: the magnitude of interhospital cost variation as a surrogate for the need for and potential effect of CER at the patient level and the cumulative fiscal burden of this cost variation when considering the case volume from all hospitals as a surrogate for public health relevance. Design, Setting, and Participants This was a cohort study of patients undergoing 1 of the 30 most costly pediatric surgical operations at 45 children’s hospitals between January 1, 2014, and September 30, 2015. Cost data were extracted from the Pediatric Health Information System database and adjusted for differences in unit-based costing at the hospital level and for differences in case mix and disease severity at the patient level. Main Outcomes and Measures First, the width of the interquartile range (WIQR) of the adjusted procedure-specific median cost across hospitals. Second, the procedure-specific cost variation burden, which was calculated as the aggregate sum of absolute cost differences between the overall adjusted median cost derived from all patients treated at all hospitals and the adjusted cost of each individual patient treated at all hospitals. Results A total of 92 535 encounters were analyzed. The median number of encounters per hospital was 2011 (interquartile range [IQR], 1224-2619), and the median number of encounters per procedure was 610 (IQR, 442-2610). In the final cohort, 66.9% (n = 61 933) of the patients were male, and the median age was 7 years (IQR, 1.9-12.3 years). Cost variation at the hospital level was greatest for gastroschisis (WIQR,