A Review of Hot Deck Imputation for Survey Non-response

Association Between Treatment Facility Volume and Mortality of Patients With Multiple Myeloma

Purpose To determine the association between the number of patients with multiple myeloma (MM) treated annually at a treatment facility (volume) and all-cause mortality (outcome). Methods Using the National Cancer Database, we identified patients diagnosed with MM between 2003 and 2011. We classified the facilities by quartiles (Q; mean patients with MM treated per year): Q1: < 3.6; Q2: 3.6 to 6.1, Q3: 6.1 to 10.3, and Q4: > 10.3. We used random intercepts to account for clustering of patients within facilities and Cox regression to determine the volume-outcome relationship, adjusting for demographic (sex, age, race, ethnicity), socioeconomic (income, education, insurance type), geographic (area of residence, treatment facility location, travel distance), and comorbid (Charlson-Deyo score) factors and year of diagnosis. Results There were 94,722 patients with MM treated at 1,333 facilities. The median age at diagnosis was 67 years, and 54.7% were men. The median annual facility volume was 6.1 patients per year (range, 0.2 to 109.9). The distribution of patients according to facility volume was: Q1: 5.2%, Q2: 12.6%, Q3: 21.9%, and Q4: 60.3%. The unadjusted median overall survival by facility volume was: Q1: 26.9 months, Q2: 29.1 months, Q3: 31.9 months, and Q4: 49.1 months ( P < .001). Multivariable analysis showed that facility volume was independently associated with all-cause mortality. Compared with patients treated at Q4 facilities, patients treated at lower-quartile facilities had a higher risk of death (Q3 hazard ratio [HR], 1.12 [95% CI, 1.08 to 1.16]; Q2 HR, 1.17 [95% CI, 1.12 to 1.21]; Q1 HR, 1.22 [95% CI, 1.17 to 1.28]). Conclusion Patients who were treated for MM at higher-volume facilities had a lower risk of mortality compared with those who were treated at lower-volume facilities.

HMG-CoAR expression in male breast cancer: relationship with hormone receptors, Hippo transducers and survival outcomes

Male breast cancer (MBC) is a rare hormone-driven disease often associated with obesity. HMG-CoAR is the central enzyme of the mevalonate pathway, a molecular route deputed to produce cholesterol and steroid-based hormones. HMG-CoAR regulates the oncogenic Hippo transducers TAZ/YAP whose expression was previously associated with shorter survival in MBC. 225 MBC samples were immunostained for HMG-CoAR and 124 were considered eligible for exploring its relationship with hormone receptors (ER, PgR, AR), Hippo transducers and survival outcomes. HMG-CoAR was positively associated with the expression of hormone receptors (ER, PgR, AR) and Hippo transducers. Overall survival was longer in patients with HMG-CoAR-positive tumors compared with their negative counterparts (p = 0.031). Five- and 10-year survival outcomes were better in patients whose tumors expressed HMG-CoAR (p = 0.044 and p = 0.043). Uni- and multivariate analyses for 10-year survival suggested that HMG-CoAR expression is a protective factor (HR 0.50, 95% CI: 0.25–0.99, p = 0.048 and HR 0.53, 95% CI: 0.26–1.07, p = 0.078). Results were confirmed in a sensitivity analysis by excluding uncommon histotypes (multivariate Cox: HR 0.45, 95% CI: 0.21–0.97, p = 0.043). A positive relationship emerged between HMG-CoAR, hormone receptors and TAZ/YAP, suggesting a connection between the mevalonate pathway, the hormonal milieu and Hippo in MBC. Moreover, HMG-CoAR expression may be a favorable prognostic indicator.

Handling missing rows in multi-omics data integration: multiple imputation in multiple factor analysis framework

Background

In omics data integration studies, it is common, for a variety of reasons, for some individuals to not be present in all data tables. Missing row values are challenging to deal with because most statistical methods cannot be directly applied to incomplete datasets. To overcome this issue, we propose a multiple imputation (MI) approach in a multivariate framework. In this study, we focus on multiple factor analysis (MFA) as a tool to compare and integrate multiple layers of information. MI involves filling the missing rows with plausible values, resulting in M completed datasets. MFA is then applied to each completed dataset to produce M different configurations (the matrices of coordinates of individuals). Finally, the M configurations are combined to yield a single consensus solution.

Results

We assessed the performance of our method, named MI-MFA, on two real omics datasets. Incomplete artificial datasets with different patterns of missingness were created from these data. The MI-MFA results were compared with two other approaches i.e., regularized iterative MFA (RI-MFA) and mean variable imputation (MVI-MFA). For each configuration resulting from these three strategies, the suitability of the solution was determined against the true MFA configuration obtained from the original data and a comprehensive graphical comparison showing how the MI-, RI- or MVI-MFA configurations diverge from the true configuration was produced. Two approaches i.e., confidence ellipses and convex hulls, to visualize and assess the uncertainty due to missing values were also described. We showed how the areas of ellipses and convex hulls increased with the number of missing individuals. A free and easy-to-use code was proposed to implement the MI-MFA method in the R statistical environment.

Conclusions

We believe that MI-MFA provides a useful and attractive method for estimating the coordinates of individuals on the first MFA components despite missing rows. MI-MFA configurations were close to the true configuration even when many individuals were missing in several data tables. This method takes into account the uncertainty of MI-MFA configurations induced by the missing rows, thereby allowing the reliability of the results to be evaluated.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-016-1273-5) contains supplementary material, which is available to authorized users.

A Type A and Type D Combined Personality Typology in Essential Hypertension and Acute Coronary Syndrome Patients: Associations with Demographic, Psychological, Clinical, and Lifestyle Indicators

Many studies have focused on Type A and Type D personality types in the context of cardiovascular diseases (CVDs), but nothing is known about how these personality types combine to create new profiles. The present study aimed to develop a typology of Type A and Type D personality in two groups of patients affected by and at risk for coronary disease. The study involved 711 patients: 51.6% with acute coronary syndrome, 48.4% with essential hypertension (mean age = 56.4 years; SD = 9.7 years; 70.7% men). Cluster analysis was applied. External variables, such as socio-demographic, psychological, lifestyle, and clinical parameters, were assessed. Six groups, each with its own unique combined personality profile scores, were identified: Type D, Type A-Negatively Affected, Not Type A-Negatively Affected, Socially Inhibited-Positively Affected, Not Socially Inhibited, and Not Type A-Not Type D. The Type A-Negatively Affected cluster and, to a lesser extent, the Type D cluster, displayed the worst profile: namely higher total cardiovascular risk index, physical inactivity, higher anxiety and depression, and lower self-esteem, optimism, and health status. Identifying combined personality profiles is important in clinical research and practice in cardiovascular diseases. Practical implications are discussed.

MULTIPLE IMPUTATION FOR MISSINGNESS DUE TO NONLINKAGE AND PROGRAM CHARACTERISTICS: A CASE STUDY OF THE NATIONAL HEALTH INTERVIEW SURVEY LINKED TO MEDICARE CLAIMS

Record linkage is a valuable and efficient tool for connecting information from different data sources. The National Center for Health Statistics (NCHS) has linked its population-based health surveys with administrative data, including Medicare enrollment and claims records. However, the linked NCHS-Medicare files are subject to missing data; first, not all survey participants agree to record linkage, and second, Medicare claims data are only consistently available for beneficiaries enrolled in the Fee-for-Service (FFS) program, not in Medicare Advantage (MA) plans. In this research, we examine the usefulness of multiple imputation for handling missing data in linked National Health Interview Survey (NHIS)-Medicare files. The motivating example is a study of mammography status from 1999 to 2004 among women aged 65 years and older enrolled in the FFS program. In our example, mammography screening status and FFS/MA plan type are missing for NHIS survey participants who were not linkage eligible. Mammography status is also missing for linked participants in an MA plan. We explore three imputation approaches: (i) imputing screening status first, (ii) imputing FFS/MA plan type first, (iii) and imputing the two longitudinal processes simultaneously. We conduct simulation studies to evaluate these methods and compare them using the linked NHIS-Medicare files. The imputation procedures described in our paper would also be applicable to other public health-related research using linked data files with missing data issues arising from program characteristics (e.g., intermittent enrollment or data collection) reflected in administrative data and linkage eligibility by survey participants.

Media Use and Exposure to Graphic Content in the Week Following the Boston Marathon Bombings

Traditional and new media inform and expose the public to potentially distressing graphic content following disasters, but predictors of media use have received limited attention. We examine media-use patterns after the Boston Marathon bombings (BMB) in a representative national U.S. sample (n = 2888), with representative oversamples from metropolitan Boston (n = 845) and New York City (n = 941). Respondents completed an Internet-based survey 2-4 weeks post-BMB. Use of traditional media was correlated with older age, prior indirect media-based exposure to collective traumas, and direct BMB exposure. New media use was correlated with younger age and prior direct exposure to collective traumas. Increased television and online news viewing were associated with exposure to more graphic content. The relationship between traditional and new media was stronger for young adults than all other age groups. We offer insights about the relationship between prior collective trauma exposures and media use following subsequent disasters and identify media sources likely to expose people to graphic content.

Facility-Level Factors Influencing Retention of Patients in HIV Care in East Africa

Losses to follow-up (LTFU) remain an important programmatic challenge. While numerous patient-level factors have been associated with LTFU, less is known about facility-level factors. Data from the East African International epidemiologic Databases to Evaluate AIDS (EA-IeDEA) Consortium was used to identify facility-level factors associated with LTFU in Kenya, Tanzania and Uganda. Patients were defined as LTFU if they had no visit within 12 months of the study endpoint for pre-ART patients or 6 months for patients on ART. Adjusting for patient factors, shared frailty proportional hazard models were used to identify the facility-level factors associated with LTFU for the pre- and post-ART periods. Data from 77,362 patients and 29 facilities were analyzed. Median age at enrolment was 36.0 years (Interquartile Range: 30.1, 43.1), 63.9% were women and 58.3% initiated ART. Rates (95% Confidence Interval) of LTFU were 25.1 (24.7–25.6) and 16.7 (16.3–17.2) per 100 person-years in the pre-ART and post-ART periods, respectively. Facility-level factors associated with increased LTFU included secondary-level care, HIV RNA PCR turnaround time >14 days, and no onsite availability of CD4 testing. Increased LTFU was also observed when no nutritional supplements were provided (pre-ART only), when TB patients were treated within the HIV program (pre-ART only), and when the facility was open ≤4 mornings per week (ART only). Our findings suggest that facility-based strategies such as point of care laboratory testing and separate clinic spaces for TB patients may improve retention.

Antenatal care use in urban areas in two European countries: Predisposing, enabling and pregnancy-related determinants in Belgium and the Netherlands

BACKGROUND

Examining determinants of antenatal care (ANC) is important to stimulate equitable distribution of ANC across Europe. This study (1) compares ANC utilisation in Belgium and the Netherlands and (2) identifies predisposing, enabling and pregnancy-related determinants.

METHODS

Secondary data analysis is performed using data from Belgium, and the Netherlands. The content and timing of care during pregnancy (CTP) tool measured ANC use. Non-parametric tests and ordinal logistic regression are performed to gain insight in the determinants of health care use.

RESULTS

Dutch women receive appropriate ANC more often than Belgian women. Multivariate analysis showed that lower education, unemployment, lower continuity of care and non-attendance of antenatal classes are associated with a lower likelihood of having more appropriate ANC.

CONCLUSIONS

Predisposing and pregnancy related variables are most important to influence the content and timing of ANC, irrespective of the country women live in. Lower health literacy in socially vulnerable women might explain the predisposing determinants of health care use in both countries. Stimulating accessibility to antenatal courses or organising public education are recommendations for practice. Regarding pregnancy-related determinants, improving continuity of care can optimise ANC use in both countries.

Suicidality and profiles of childhood adversities, conflict related trauma and psychopathology in the Northern Ireland population

BACKGROUND

Over 30 years of conflict in Northern Ireland (NI) has impacted on the population's mental health. However, childhood adversities may add to the psychological impact of conflict. The aims of the study were to assess co-occurrence across childhood adversities, conflict related traumas, and psychological health, then explore demographic variations between identified classes, and examine the impact of class membership on suicidal ideation and behaviour.

METHOD

Data was obtained from the Northern Ireland Study of Health and Stress, a representative epidemiological study which used the CIDI to assess psychopathology and related risk factors in the NI population (N=4340, part 2 n=1986; response rate 64%).

RESULTS

Latent Class Analysis uncovered 4 discrete profiles; a conflict class (n=191; 9.6%), a multi-risk class endorsing elevated levels of childhood adversities, conflict related traumas and psychopathology (n=85; 4.3%), a psychopathology class (n=290; 14.6%), and a low risk class (n=1420; 71.5%). Multinomial logistic regression analysis revealed that individuals who grew up during the worst years of the Troubles were more likely to have experienced multiple traumas and psychopathology. Individuals in the multi-risk class were more than fifteen times more likely to endorse suicidal ideation and behaviour.

LIMITATIONS

The main limitations are that the study may not be fully representative of the NI population due to the exclusion criteria applied and also the possible misclassification of conflict related events.

CONCLUSIONS

The findings indicate that treatment providers should be cognisant that those with wide ranging adversity profiles are those also likely to be reporting psychological distress and suicidality.

Toward an Understanding of Citywide Urban Environmental Governance: An Examination of Stewardship Networks in Baltimore and Seattle

Efforts to create more sustainable cities are evident in the proliferation of sustainability policies in cities worldwide. It has become widely proposed that the success of these urban sustainability initiatives will require city agencies to partner with, and even cede authority to, organizations from other sectors and levels of government. Yet the resulting collaborative networks are often poorly understood, and the study of large whole networks has been a challenge for researchers. We believe that a better understanding of citywide environmental governance networks can inform evaluations of their effectiveness, thus contributing to improved environmental management. Through two citywide surveys in Baltimore and Seattle, we collected data on the attributes of environmental stewardship organizations and their network relationships. We applied missing data treatment approaches and conducted social network and comparative analyses to examine (a) the organizational composition of the network, and (b) how information and knowledge are shared throughout the network. Findings revealed similarities in the number of actors and their distribution across sectors, but considerable variation in the types and locations of environmental stewardship activities, and in the number and distribution of network ties in the networks of each city. We discuss the results and potential implications of network research for urban sustainability governance.

Nearest neighbor imputation algorithms: a critical evaluation

Background

Nearest neighbor (NN) imputation algorithms are efficient methods to fill in missing data where each missing value on some records is replaced by a value obtained from related cases in the whole set of records. Besides the capability to substitute the missing data with plausible values that are as close as possible to the true value, imputation algorithms should preserve the original data structure and avoid to distort the distribution of the imputed variable. Despite the efficiency of NN algorithms little is known about the effect of these methods on data structure.

Methods

Simulation on synthetic datasets with different patterns and degrees of missingness were conducted to evaluate the performance of NN with one single neighbor (1NN) and with k neighbors without (kNN) or with weighting (wkNN) in the context of different learning frameworks: plain set, reduced set after ReliefF filtering, bagging, random choice of attributes, bagging combined with random choice of attributes (Random-Forest-like method).

Results

Whatever the framework, kNN usually outperformed 1NN in terms of precision of imputation and reduced errors in inferential statistics, 1NN was however the only method capable of preserving the data structure and data were distorted even when small values of k neighbors were considered; distortion was more severe for resampling schemas.

Conclusions

The use of three neighbors in conjunction with ReliefF seems to provide the best trade-off between imputation error and preservation of the data structure. The very same conclusions can be drawn when imputation experiments were conducted on the single proton emission computed tomography (SPECTF) heart dataset after introduction of missing data completely at random.

Short-term and long-term effects of a progressive resistance and balance exercise program in individuals with chronic stroke: a randomized controlled trial

PURPOSE

To evaluate the effects of progressive resistance and balance (PRB) exercises on physical and psychological functions of post-stroke individuals.

MATERIALS AND METHODS

In a randomized controlled trial with follow-up at 3, 6 and 15 months, 67 community-living individuals (76% male; 65-85 years) with a stroke 1-3 years previously were allocated to an intervention group (IG, n = 34; PRB exercises combined with motivational group discussions twice weekly for 3 months) or a control group (CG, n = 33). The primary outcomes were balance (Berg Balance Scale, 0-56 points) and mobility (Short Physical Performance Battery, 0-12 points) at 3 months. The secondary outcomes were 10 m comfortable walking speed, physical activity levels, health-related quality of life, depression and fall-related self-efficacy.

RESULTS

At 3 months, the IG exhibited significant improvements in balance (MD 2.5 versus 0 points; effect size [ES], 0.72; p < 0.01) and comfortable walking speed (MD 0.04 versus -0.05 m/s; ES, 0.68; p = 0.01) relative to the CG. A faster walking speed persisted at 6 months. No differences were found for the other outcomes.

CONCLUSIONS

In chronic stroke patients, 3 months of PRB exercises and motivational discussions induced improvements in balance at 3 months and in walking speed at 3 and 6 months. Implications for Rehabilitation A progressive resistance and balance exercise program supported by motivational group discussions and one home-based exercise appears to be an effective means of improving the short-term balance and the walking speed in individuals with chronic stroke. People with poor balance and motor function discontinued the study more often and may require additional support. There is a need for powerful and cost-effective strategies that target changes in behavior to obtain long-term changes in physical function after exercising.

Fraction of Missing Information (γ) at Different Missing Data Fractions in the 2012 NAMCS Physician Workflow Mail Survey

In his 1987 classic book on multiple imputation (MI), Rubin used the fraction of missing information, γ, to define the relative efficiency (RE) of MI as RE = (1 + γ/m)^-1/2, where m is the number of imputations, leading to the conclusion that a small m (≤5) would be sufficient for MI. However, evidence has been accumulating that many more imputations are needed. Why would the apparently sufficient m deduced from the RE be actually too small? The answer may lie with γ. In this research, γ was determined at the fractions of missing data (δ) of 4%, 10%, 20%, and 29% using the 2012 Physician Workflow Mail Survey of the National Ambulatory Medical Care Survey (NAMCS). The γ values were strikingly small, ranging in the order of 10^-6 to 0.01. As δ increased, γ usually increased but sometimes decreased. How the data were analysed had the dominating effects on γ, overshadowing the effect of δ. The results suggest that it is impossible to predict γ using δ and that it may not be appropriate to use the γ-based RE to determine sufficient m.

Multiple- vs Non- or Single-Imputation based Fuzzy Clustering for Incomplete Longitudinal Behavioral Intervention Data

Disentangling patients' behavioral variations is a critical step for better understanding an intervention's effects on individual outcomes. Missing data commonly exist in longitudinal behavioral intervention studies. Multiple imputation (MI) has been well studied for missing data analyses in the statistical field, however, has not yet been scrutinized for clustering or unsupervised learning, which are important techniques for explaining the heterogeneity of treatment effects. Built upon previous work on MI fuzzy clustering, this paper theoretically, empirically and numerically demonstrate how MI-based approach can reduce the uncertainty of clustering accuracy in comparison to non-and single-imputation based clustering approach. This paper advances our understanding of the utility and strength of multiple-imputation (MI) based fuzzy clustering approach to processing incomplete longitudinal behavioral intervention data.

Psychometric properties of the 7-item game addiction scale among french and German speaking adults

BACKGROUND

The 7-item Game Addiction Scale (GAS) is a used to screen for addictive game use. Both cross cross-linguistic validation and validation in French and German is needed in adult samples. The objective of the study is to assess the factorial structure of the French and German versions of the GAS among adults.

METHODS

Two samples of men from French (N = 3318) and German (N = 2665) language areas of Switzerland were assessed with the GAS, the Major Depression Inventory (MDI), the Brief Sensation Seeking Scale, and the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ-50-cc). They were also assessed for cannabis and alcohol use.

RESULTS

The internal consistency of the scale was satisfactory (Cronbach α = 0.85). A one-factor solution was found in both samples. Small and positive associations were found between GAS scores and the MDI, as well as the Neuroticism-Anxiety and Aggression-Hostility subscales of the ZKPQ-50-cc. A small negative association was found with the ZKPQ-50-cc Sociability subscale.

CONCLUSION

The GAS, in its French and German versions, is appropriate for the assessment of game addiction among adults.

Retrospective benzene exposure assessment for a multi-center case-cohort study of benzene-exposed workers in China

Quality of exposure assessment has been shown to be related to the ability to detect risk of lymphohematopoietic disorders in epidemiological investigations of benzene, especially at low levels of exposure. We set out to build a statistical model for reconstructing exposure levels for 2898 subjects from 501 factories that were part of a nested case-cohort study within the NCI-CAPM cohort of more than 110,000 workers. We used a hierarchical model to allow for clustering of measurements by factory, workshop, job, and date. To calibrate the model we used historical routine monitoring data. Measurements below the limit of detection were accommodated by constructing a censored data likelihood. Potential non-linear and industry-specific time-trends and predictor effects were incorporated using regression splines and random effects. A partial validation of predicted exposures in 2004/2005 was performed through comparison with full-shift measurements from an exposure survey in facilities that were still open. Median cumulative exposure to benzene at age 50 for subjects that ever held an exposed job (n=1175) was 509 mg/m(3) years. Direct comparison of model estimates with measured full-shift personal exposure in the 2004/2005 survey showed moderate correlation and a potential downward bias at low (<1 mg/m(3)) exposure estimates. The modeling framework enabled us to deal with the data complexities generally found in studies using historical exposure data in a comprehensive way and we therefore expect to be able to investigate effects at relatively low exposure levels.

Mitonuclear Epistasis for Development Time and Its Modification by Diet in Drosophila

Mitochondrial (mtDNA) and nuclear genes have to operate in a coordinated manner to maintain organismal function, and the regulation of this homeostasis presents a substantial source of potential epistatic (G × G) interactions. How these interactions shape the fitness landscape is poorly understood. Here we developed a novel mitonuclear epistasis model, using selected strains of the Drosophila Genetic Reference Panel (DGRP) and mitochondrial genomes from within Drosophila melanogaster and D. simulans to test the hypothesis that mtDNA × nDNA interactions influence fitness. In total we built 72 genotypes (12 nuclear backgrounds × 6 mtDNA haplotypes, with 3 from each species) to dissect the relationship between genotype and phenotype. Each genotype was assayed on four food environments. We found considerable variation in several phenotypes, including development time and egg-to-adult viability, and this variation was partitioned into genetic (G), environmental (E), and higher-order (G × G, G × E, and G × G × E) components. Food type had a significant impact on development time and also modified mitonuclear epistases, evidencing a broad spectrum of G × G × E across these genotypes. Nuclear background effects were substantial, followed by mtDNA effects and their G × G interaction. The species of mtDNA haplotype had negligible effects on phenotypic variation and there was no evidence that mtDNA variation has different effects on male and female fitness traits. Our results demonstrate that mitonuclear epistases are context dependent, suggesting the selective pressure acting on mitonuclear genotypes may vary with food environment in a genotype-specific manner.

Gender Differences in Spousal Care Across the Later Life Course

Spouses often serve as the primary caregivers to their ill or disabled partners. Studies have shown that men receive more care from their wives than vice versa, but few studies have focused on how the gender gap in care varies across the later life course. Drawing on data from the Health and Retirement Study, this study examined the moderating effects of age, gender, and full-time employment on married women's and men's receipt of spousal care. This study found that among community-dwelling married adults, the gender gap in care was larger among those in middle age (50-65) than it was among those in older age. As women and men aged, the gender gap decreased primarily because men left full-time work and increased the amount of time that they spent caring for their wives. As gender differences in full-time employment narrowed, the gender gap in spousal care narrowed.

Missing value imputation for physical activity data measured by accelerometer

An accelerometer, a wearable motion sensor on the hip or wrist, is becoming a popular tool in clinical and epidemiological studies for measuring the physical activity. Such data provide a series of activity counts at every minute or even more often and displays a person's activity pattern throughout a day. Unfortunately, the collected data can include irregular missing intervals because of noncompliance of participants and therefore make the statistical analysis more challenging. The purpose of this study is to develop a novel imputation method to handle the multivariate count data, motivated by the accelerometer data structure. We specify the predictive distribution of the missing data with a mixture of zero-inflated Poisson and Log-normal distribution, which is shown to be effective to deal with the minute-by-minute autocorrelation as well as under- and over-dispersion of count data. The imputation is performed at the minute level and follows the principles of multiple imputation using a fully conditional specification with the chained algorithm. To facilitate the practical use of this method, we provide an R package accelmissing. Our method is demonstrated using 2003-2004 National Health and Nutrition Examination Survey data.

Redrawing the US Obesity Landscape: Bias-Corrected Estimates of State-Specific Adult Obesity Prevalence

BACKGROUND

State-level estimates from the Centers for Disease Control and Prevention (CDC) underestimate the obesity epidemic because they use self-reported height and weight. We describe a novel bias-correction method and produce corrected state-level estimates of obesity and severe obesity.

METHODS

Using non-parametric statistical matching, we adjusted self-reported data from the Behavioral Risk Factor Surveillance System (BRFSS) 2013 (n = 386,795) using measured data from the National Health and Nutrition Examination Survey (NHANES) (n = 16,924). We validated our national estimates against NHANES and estimated bias-corrected state-specific prevalence of obesity (BMI≥30) and severe obesity (BMI≥35). We compared these results with previous adjustment methods.

RESULTS

Compared to NHANES, self-reported BRFSS data underestimated national prevalence of obesity by 16% (28.67% vs 34.01%), and severe obesity by 23% (11.03% vs 14.26%). Our method was not significantly different from NHANES for obesity or severe obesity, while previous methods underestimated both. Only four states had a corrected obesity prevalence below 30%, with four exceeding 40%-in contrast, most states were below 30% in CDC maps.

CONCLUSIONS

Twelve million adults with obesity (including 6.7 million with severe obesity) were misclassified by CDC state-level estimates. Previous bias-correction methods also resulted in underestimates. Accurate state-level estimates are necessary to plan for resources to address the obesity epidemic.

Effectiveness of Simeprevir Plus Sofosbuvir, With or Without Ribavirin, in Real-World Patients With HCV Genotype 1 Infection

BACKGROUND & AIMS

The interferon-free regimen of simeprevir plus sofosbuvir was recommended by professional guidelines for certain patients with hepatitis C virus (HCV) genotype 1 infection based on the findings of a phase 2 trial. We aimed to evaluate the safety and efficacy of this regimen in clinical practice settings in North America.

METHODS

We collected demographic, clinical, and virologic data, as well as reports of adverse outcomes, from sequential participants in HCV-TARGET--a prospective observational cohort study of patients undergoing HCV treatment in routine clinical care settings. From January through October 2014, there were 836 patients with HCV genotype 1 infection who began 12 weeks of treatment with simeprevir plus sofosbuvir (treatment duration of up to 16 weeks); 169 of these patients received ribavirin. Most patients were male (61%), Caucasian (76%), or black (13%); 59% had cirrhosis. Most patients had failed prior treatment with peginterferon and ribavirin without (46%) or with telaprevir or boceprevir (12%). The primary outcome was sustained virologic response (SVR), defined as the level of HCV RNA below quantification at least 64 days after the end of treatment (beginning of week 12 after treatment--a 2-week window). Logistic regression models with inverse probability weights were constructed to adjust for baseline covariates and potential selection bias.

RESULTS

The overall SVR rate was 84% (675 of 802 patients, 95% confidence interval, 81%-87%). Model-adjusted estimates indicate patients with cirrhosis, prior decompensation, and previous protease inhibitor treatments were less likely to achieve an SVR. The addition of ribavirin had no detectable effects on SVR. The most common adverse events were fatigue, headache, nausea, rash, and insomnia. Serious adverse events and treatment discontinuation occurred in only 5% and 3% of participants, respectively.

CONCLUSIONS

In a large prospective observational cohort study, a 12-week regimen of simeprevir plus sofosbuvir was associated with high rates of SVR and infrequent treatment discontinuation. ClinicalTrials.gov: NCT01474811.

Child Wasting in Emergency Pockets: A Meta-Analysis of Small-Scale Surveys from Ethiopia

Child undernutrition is a major public health concern in Ethiopia (stunting national prevalence: 44%; wasting: 10%), despite the overall improvement in child health status during the last decade. Hundreds of small-scale surveys are conducted in Ethiopia's emergency pockets under ENCU's supervision. We reviewed the evidence from small-scale surveys conducted between 2008 and 2013 with two objectives: to provide a summary estimate of wasting prevalence from emergency pockets and to examine reasons for variation in prevalence estimates. We created a dataset by combining data from the Complex Emergency Database, the Famine Early Warning System Network and the Armed Conflict Location Event Data. We conducted a meta-analysis of small-scale surveys using a random effects model with known within-study heterogeneity. The influence of survey covariates on estimated prevalence was investigated with meta-regression techniques. We included 158 surveys in the analysis. A high degree of heterogeneity among surveys was observed. The overall estimate of wasting prevalence was 10.6% (95% CI 9.8-11.4), with differences among regions and between residents and refugees. Meta-regression results showed that vaccination coverage, child mortality, diarrhea prevalence and food insecurity are significantly associated with wasting prevalence. Child care and displacement status were not. Aggregated analysis of small-scale surveys provides insights into the prevalence of wasting and factors explaining its variation. It can also guide survey planning towards areas with limited data availability.

Prevalence of sarcopenia in older Brazilians: A systematic review and meta-analysis

AIM

Sarcopenia is the age-related loss of muscle mass and function that evolves into disability, loss of independence and death. In Brazil the number of older people is rapidly growing, resulting in an increased prevalence of chronic conditions associated with old age. As prevalence estimates provide essential information to policymakers when developing healthcare strategies, this systematic review and meta-analysis aimed to estimate the prevalence of sarcopenia in older Brazilians.

METHODS

Electronic database searches and hand-searching in relevant journals and reference lists were carried out without language restriction. Studies that reported the prevalence of sarcopenia in Brazilians aged 60 years or older were considered for inclusion. Sarcopenia was defined as low muscle mass, low muscle function or low muscle mass and function. Meta-analysis was carried out using a random-effects model.

RESULTS

A total of 31 studies were included pooling 9416 participants. The overall prevalence of sarcopenia in older Brazilians was 17.0% (95% CI 13.0-22.0). Sensitivity analysis showed rates of 20.0% (95% CI 11.0-32.0) in women and 12.0% (95% CI 9.0-16.0) in men. Prevalence was 16.0% (95% CI 12.0-23.0) based on low muscle mass and function; and 17.0% (95% CI 9.0-31.0) based only on low muscle mass. The difference between these two criteria was not significant (P = 0.96).

CONCLUSIONS

Sarcopenia is an emerging public health issue in Brazil. Attention should be paid to changes in prevalence rates over the next years because of the increase in the older population. Geriatr Gerontol Int 2017; 17: 5-16.

Complementary and Alternative Medicine Use in the US Adult Low Back Pain Population

Background:

Many people suffering from low back pain (LBP) have found conventional medical treatments to be ineffective for managing their LBP and are increasingly turning to complementary and alternative medicine (CAM) to find pain relief. A comprehensive picture of CAM use in the LBP population, including all of the most commonly used modalities, is needed.

Study Objective:

To examine prevalence and perceived benefit of CAM use within the US LBP population by limiting vs nonlimiting LBP and to evaluate the odds of past year CAM use within the LBP population

Methods:

Data are from the 2012 National Health Interview Survey, Alternative Health Supplement. We examined a nationally representative sample of US adults with LBP (N=9665 unweighted). Multiple logistic regression was used to estimate the odds of past year CAM use.

Results:

In all, 41.2% of the LBP population used CAM in the past year, with higher use reported among those with limiting LBP. The most popular therapies used in the LBP population included herbal supplements, chiropractic manipulation, and massage. The majority of the LBP population used CAM specifically to treat back pain, and 58.1% of those who used CAM for their back pain perceived a great deal of benefit.

Conclusion:

The results are indicative of CAM becoming an increasingly important component of care for people with LBP. Additional understanding of patterns of CAM use among the LBP population will help health professionals make more informed care decisions and guide investigators in development of future back pain–related CAM research.

Vulnerable Populations Perceive Their Health as at Risk from Climate Change

Climate change is already taking a toll on human health, a toll that is likely to increase in coming decades. The relationship between risk perceptions and vulnerability to climate change's health threats has received little attention, even though an understanding of the dynamics of adaptation among particularly susceptible populations is becoming increasingly important. We demonstrate that some people whose health will suffer the greatest harms from climate change-due to social vulnerability, health susceptibility, and exposure to hazards-already feel they are at risk. In a 2013 survey we measured Maryland residents' climate beliefs, health risk perceptions, and household social vulnerability characteristics, including medical conditions (n = 2126). We paired survey responses with secondary data sources for residence in a floodplain and/or urban heat island to predict perceptions of personal and household climate health risk. General health risk perceptions, political ideology, and climate beliefs are the strongest predictors. Yet, people in households with the following characteristics also see themselves at higher risk: members with one or more medical conditions or disabilities; low income; racial/ethnic minorities; and residence in a floodplain. In light of these results, climate health communication among vulnerable populations should emphasize protective actions instead of risk messages.

Effects of protein-rich nutritional supplementation and bisphosphonates on body composition, handgrip strength and health-related quality of life after hip fracture: a 12-month randomized controlled study

BACKGROUND

The catabolic state that follows hip fracture contributes to loss of muscle mass and strength, that is sarcopenia, which impacts functional ability and health-related quality of life. Measures to prevent such long-term postoperative consequences are of important concern. The aim of this study was to evaluate the combined effects of protein-rich nutritional supplementation and bisphosphonate on body composition, handgrip strength and health-related quality of life following hip fracture.

METHODS

The study included 79 men and women with hip fracture, mean age 79 years (SD 9), without severe cognitive impairment, who were ambulatory and living independently before fracture. Patients were randomized postoperatively to receive liquid supplementation that provided 40 g of protein and 600 kcal daily for six months after the fracture, in addition to bisphosphonates once weekly for 12 months (group N, n = 26), or bisphosphonates alone once weekly for 12 months (group B, n = 28). All patients, including the controls (group C, n = 25) received calcium 1 g and vitamin D3 800 IU daily. Body composition as measured by dual-energy X-ray absorptiometry (DXA), handgrip strength (HGS) and health-related quality of life (HRQoL) were registered at baseline, six and 12 months postoperatively.

RESULTS

There were no differences among the groups regarding change in fat-free mass index (FFMI), HGS, or HRQoL during the study year. Intra-group analyses showed improvement of HGS between baseline and six months in the N group (P = 0.04). HRQoL decreased during the first year in the C and B groups (P = 0.03 and P = 0.01, respectively) but not in the nutritional supplementation N group (P = 0.22).

CONCLUSIONS

Protein-rich nutritional supplementation was unable to preserve FFMI more effectively than vitamin D and calcium alone, or combined with bisphosphonate, in this relatively healthy group of hip fracture patients. However, trends toward positive effects on both HGS and HRQoL were observed following nutritional supplementation.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01950169 (Date of registration 23 Sept 2013).

Combining fractional polynomial model building with multiple imputation

Multivariable fractional polynomial (MFP) models are commonly used in medical research. The datasets in which MFP models are applied often contain covariates with missing values. To handle the missing values, we describe methods for combining multiple imputation with MFP modelling, considering in turn three issues: first, how to impute so that the imputation model does not favour certain fractional polynomial (FP) models over others; second, how to estimate the FP exponents in multiply imputed data; and third, how to choose between models of differing complexity. Two imputation methods are outlined for different settings. For model selection, methods based on Wald-type statistics and weighted likelihood-ratio tests are proposed and evaluated in simulation studies. The Wald-based method is very slightly better at estimating FP exponents. Type I error rates are very similar for both methods, although slightly less well controlled than analysis of complete records; however, there is potential for substantial gains in power over the analysis of complete records. We illustrate the two methods in a dataset from five trauma registries for which a prognostic model has previously been published, contrasting the selected models with that obtained by analysing the complete records only.

Trajectories of care home residents during the last month of life: the case of France

This paper examines some demographic and medical factors associated with the likelihood of residing in a care home during the last month of life for persons aged 70 and over in France and, if so, of remaining in the care home throughout or being transferred to hospital. The data are from the Fin de vie en France (End of Life in France) survey undertaken in 2010. During the last month of life, very old people are more likely to be living in a care home but are not less likely to be transferred to hospital. Medical conditions and residential trajectories are closely related. People with dementia or mental disorders are more likely to live in a care home and, if so, to stay there until they die. Compared to care homes, a more technical and medication-based approach is taken in hospitals and care home residents who are transferred to hospital more often receive medication while those remaining in care homes more often receive support from a psychologist. In hospitals as in care homes, few older persons had recourse to advance directives and hospice programmes were not widespread. Promoting these two factors may help to increase the quality of end of life and facilitate an ethical approach to end-of-life care.

Patterns and Predictors of Use of Anticoagulants for the Treatment of Venous Thromboembolism Following Approval of Rivaroxaban

BACKGROUND

Few studies have identified patterns and predictors of use of direct oral anticoagulants for venous thromboembolism (VTE).

OBJECTIVE

To describe the use of anticoagulants and assess predictors associated with the prescription of rivaroxaban over vitamin K antagonist (VKA) for the subsequent treatment of VTE.

METHODS

This cross-sectional study was built with all consecutive patients newly diagnosed with acute VTE admitted between February 18, 2013, and September 18, 2013, in an academic tertiary care center in Quebec, Canada. Patient characteristics and VTE treatments were described. Univariate analyses and a multiple forward stepwise logistic regression were performed to assess predictors of rivaroxaban use over VKA for the subsequent treatment of VTE.

RESULTS

The study included 256 patients, 36.7% with a diagnosis of deep vein thrombosis (DVT) and 63.3% with pulmonary embolism (PE). Mean age was 63.1 years, and 28.1% of patients had cancer-associated VTE. Overall, rivaroxaban was prescribed in 1.6% of patients for the initial treatment and in nearly 20% of patients for the subsequent treatment of VTE. Low-molecular-weight heparin and VKA were mostly prescribed. Independent predictors associated with the prescription of rivaroxaban over VKA were as follows: age < 65 years (OR: 2.86, 95% CI 1.29-6.37), a diagnosis of DVT versus PE (OR 2.54, 95% CI 1.20-5.40), and an emergency department visit rather than a hospitalization (OR 2.24, 95% CI 1.06-4.71).

CONCLUSION

Several months following its availability, rivaroxaban was rarely prescribed for acute VTE disease. It also appears to be prescribed in different patient populations than VKA.

Evaluation of techniques for handling missing cost-to-charge ratios in the USA Nationwide Inpatient Sample: a simulation study

AIM

Evaluate performance of techniques used to handle missing cost-to-charge ratio (CCR) data in the USA Healthcare Cost and Utilization Project's Nationwide Inpatient Sample.

METHODS

Four techniques to replace missing CCR data were evaluated: deleting discharges with missing CCRs (complete case analysis), reweighting as recommended by Healthcare Cost and Utilization Project, reweighting by adjustment cells and hot deck imputation by adjustment cells. Bias and root mean squared error of these techniques on hospital cost were evaluated in five disease cohorts.

RESULTS & CONCLUSION

Similar mean cost estimates would be obtained with any of the four techniques when the percentage of missing data is low (<10%). When total cost is the outcome of interest, a reweighting technique to avoid underestimation from dropping observations with missing data should be adopted.

Low Self-Control and Crime in Late Adulthood

This study investigates whether low self-control theory explains self-reported criminal activity in late adulthood. Cross-sectional survey data from telephone interviews conducted with individuals aged 60 years and older in Arizona and Florida (N = 2,000) are used. Regression analyses show that low self-control is related to criminal offending. The relationship between low self-control and offending persists after the introduction of potential mediators (e.g., unstructured socializing, negative emotions, and familial ties) and is even observed across different stages of late adulthood (i.e., young-old, old-old, and oldest-old) characterized by declining physical and cognitive abilities. Robustness checks using alternative measurement and modeling strategies also provide empirical support. Although strong causal inferences are limited by the nature of the data, the findings generally support the notion that low self-control theory partially explains criminal offending in late adulthood.

Perinatal survival and health after maternal influenza A(H1N1)pdm09 vaccination: A cohort study of pregnancies stratified by trimester of vaccination

Large cohort studies demonstrated the safety of vaccination with the AS03 adjuvanted pandemic influenza vaccine, but data on first trimester vaccination safety are limited. We conducted a nationwide register-based retrospective cohort study in Finland, included singleton pregnancies present on 01 November 2009 and followed them from 01 November 2009 until delivery. Pregnancies with abortive outcome, pregnancies that started before 01 February 2009 and pregnancies of women, who received the AS03 adjuvanted pandemic influenza vaccine prior to the onset of pregnancy, were excluded. Our main outcome measures were hazard ratios comparing the risk of stillbirth, early neonatal death, moderately preterm birth, very preterm birth, moderately low birth weight, very low birth weight, and being small for gestational age between pregnancies exposed and unexposed to maternal influenza A(H1N1)pdm09 vaccination. The study population comprised 43,604 pregnancies; 34,241 (78.5%) women were vaccinated at some stage during pregnancy. The rates of stillbirth, early neonatal death, moderately preterm birth, and moderately low birth weight were similar between pregnant women exposed and unexposed to influenza A(H1N1)pdm09 vaccination. After adjusting for known risk factors, the relative rates were 0.90 (95% confidence interval 0.55-1.45) for very preterm birth, 0.84 (0.61-1.16) for very low birth weight, and 1.17 (0.98-1.40) for being small for gestational age. Also, in the subanalysis of 7839 women vaccinated during the first trimester, the rates did not indicate that maternal vaccination during the first trimester had any adverse impact on perinatal survival and health. The risk of adverse pregnancy outcomes was not associated with the exposure to the AS03 adjuvanted pandemic influenza vaccine. This study adds reassuring evidence on the safety of AS03 adjuvanted influenza vaccines when given in the first trimester and supports the recommendation of influenza vaccination to all pregnant women through all stages of pregnancy.

Changes in Dietary Behavior among Coronary and Hypertensive Patients: A Longitudinal Investigation Using the Health Action Process Approach

BACKGROUND

Cardiovascular diseases (CVDs) are a major cause of worldwide morbidity and mortality. Nutrition plays an important role in the primary, secondary, and tertiary prevention of CVDs. The present longitudinal study used the Health Action Process Approach (HAPA) to investigate changes in dietary behavior in coronary patients (CPs) affected by acute coronary syndrome and hypertensive patients (HPs) affected by essential arterial hypertension.

METHODS

CPs (N = 250) and HPs (N = 246) completed a questionnaire during three measurement points (baseline, 6-month follow-up, and 12-month follow-up). Statistical analyses included a repeated measures ANOVA and a multi-sample structural equation model.

RESULTS

HPs showed no changes in dietary behavior, whereas CPs improved their nutrition at 6 months and then maintained the healthier diet. The multi-sample analysis indicated equivalence of the HAPA model for both patient populations.

CONCLUSIONS

These findings provide further evidence for the generalisability of the HAPA model, shedding light on dietary behavior among CVD patients and particularly on hypertensive patients which has received little attention. Moreover, the equivalence of the model suggests that the process of change is almost identical for individuals who are at high risk for a coronary event (i.e. HPs) and individuals who have already had the event (i.e. CPs).

Prescription Drug Misuse in Late Adulthood

Prescription drug misuse is a public health problem, and older adults are at high risk. The underlying factors associated with this problem in late adulthood are not well understood. Using cross-sectional data from telephone interviews with individuals aged 60 years and older in Arizona and Florida ( N = 2,000), this study tests whether hypotheses derived from general strain and low self-control theories are supported while investigating misusing prescription medication. Results from the regression analyses reveal that the association between poor health (conceptualized as a strain) and misusing prescription drugs (conceptualized as criminal coping) is partially explained by depressive symptoms (conceptualized as negative emotionality). The link between problem drinking and prescription drug misuse is fully attenuated when low self-control is included in the model. The results confirm that both theories provide insight into this public health problem and that treatment strategies should target the underlying mechanisms that lead to misuse.

Cumulative exposure to prior collective trauma and acute stress responses to the Boston marathon bombings

The role of repeated exposure to collective trauma in explaining response to subsequent community-wide trauma is poorly understood. We examined the relationship between acute stress response to the 2013 Boston Marathon bombings and prior direct and indirect media-based exposure to three collective traumatic events: the September 11, 2001 (9/11) terrorist attacks, Superstorm Sandy, and the Sandy Hook Elementary School shooting. Representative samples of residents of metropolitan Boston (n = 846) and New York City (n = 941) completed Internet-based surveys shortly after the Boston Marathon bombings. Cumulative direct exposure and indirect exposure to prior community trauma and acute stress symptoms were assessed. Acute stress levels did not differ between Boston and New York metropolitan residents. Cumulative direct and indirect, live-media-based exposure to 9/11, Superstorm Sandy, and the Sandy Hook shooting were positively associated with acute stress responses in the covariate-adjusted model. People who experience multiple community-based traumas may be sensitized to the negative impact of subsequent events, especially in communities previously exposed to similar disasters.

Development and implementation of the National Cancer Institute's Food Attitudes and Behaviors Survey to assess correlates of fruit and vegetable intake in adults

Background

Low fruit and vegetable (FV) intake is a leading risk factor for chronic disease globally as well as in the United States. Much of the population does not consume the recommended servings of FV daily. This paper describes the development of psychosocial measures of FV intake for inclusion in the U.S. National Cancer Institute’s 2007 Food Attitudes and Behaviors Survey.

Methods

This was a cross-sectional study among 3,397 adults from the United States.

Scales included conventional constructs shown to be correlated with fruit and vegetable intake (FVI) in prior studies (e.g., self-efficacy, social support), and novel constructs that have been measured in few- to- no studies (e.g., views on vegetarianism, neophobia). FVI was assessed with an eight-item screener. Exploratory factor analysis, Cronbach’s alpha, and regression analyses were conducted.

Results

Psychosocial scales with Cronbach’s alpha ≥0.68 were self-efficacy, social support, perceived barriers and benefits of eating FVs, views on vegetarianism, autonomous and controlled motivation, and preference for FVs. Conventional scales that were associated (p<0.05) with FVI were self-efficacy, social support, and perceived barriers to eating FVs. Novel scales that were associated (p<0.05) with FVI were autonomous motivation, and preference for vegetables. Other single items that were associated (p<0.05) with FVI included knowledge of FV recommendations, FVI “while growing up”, and daily water consumption.

Conclusion

These findings may inform future behavioral interventions as well as further exploration of other potential factors to promote and support FVI.