A Bayesian model for estimating multi-state disease progression

A growing number of individuals who are considered at high risk of cancer are now routinely undergoing population screening. However, noted harms such as radiation exposure, overdiagnosis, and overtreatment underscore the need for better temporal models that predict who should be screened and at what frequency. The mean sojourn time (MST), an average duration period when a tumor can be detected by imaging but with no observable clinical symptoms, is a critical variable for formulating screening policy. Estimation of MST has been long studied using continuous Markov model (CMM) with Maximum likelihood estimation (MLE). However, a lot of traditional methods assume no observation error of the imaging data, which is unlikely and can bias the estimation of the MST. In addition, the MLE may not be stably estimated when data is sparse. Addressing these shortcomings, we present a probabilistic modeling approach for periodic cancer screening data. We first model the cancer state transition using a three state CMM model, while simultaneously considering observation error. We then jointly estimate the MST and observation error within a Bayesian framework. We also consider the inclusion of covariates to estimate individualized rates of disease progression. Our approach is demonstrated on participants who underwent chest x-ray screening in the National Lung Screening Trial (NLST) and validated using posterior predictive p-values and Pearson's chi-square test. Our model demonstrates more accurate and sensible estimates of MST in comparison to MLE.

Diet Quality Affects the Playground Activities of Kenyan Children

The present study examined the effects of a school breakfast program on the activity level, emotional state, and social interactions of a group of Kenyan schoolchildren on the playground. Five hundred forty children in rural Kenya participated in the study. The first standard (grade) classes were randomly assigned to groups provided for 21 months with school breakfasts of equivalent caloric value while families with children in the control group were given a goat at the end of the study. The study aimed to determine whether enhanced caloric intake or diet quality influenced the children's behavior on the school playground. The results indicate that supplemented children were more active and showed more leadership behavior and initiative than did non-supplemented children. In addition, children given meat showed fewer periods of low activity and more leadership behaviors and initiative than did children provided entirely with vegetable source foods. These results support our previous findings from naturalistic studies in the same community that both diet quantity and quality are important for children's development.

Reliability of Clinical Assessments in Older Adults With Syncope or Near Syncope

OBJECTIVES

Clinical prediction models for risk stratification of older adults with syncope or near syncope may improve resource utilization and management. Predictors considered for inclusion into such models must be reliable. Our primary objective was to evaluate the inter-rater agreement of historical, physical examination, and electrocardiogram (ECG) findings in older adults undergoing emergency department (ED) evaluation for syncope or near syncope. Our secondary objective was to assess the level of agreement between clinicians on the patient's overall risk for death or serious cardiac outcomes.

METHODS

We conducted a cross-sectional study at 11 EDs in adults 60 years of age or older who presented with unexplained syncope or near syncope. We excluded patients with a presumptive cause of syncope (e.g., seizure) or if they were unable or unwilling to follow-up. Evaluations of the patient's past medical history and current medication use were completed by treating provider and trained research associate pairs. Evaluations of the patient's physical examination and ECG interpretation were completed by attending/resident, attending/advanced practice provider, or attending/attending pairs. All evaluations were blinded to the responses from the other rater. We calculated the percent agreement and kappa statistic for binary variables. Inter-rater agreement was considered acceptable if the kappa statistic was 0.6 or higher.

RESULTS

We obtained paired observations from 255 patients; mean (±SD) age was 73 (±9) years, 137 (54%) were male, and 204 (80%) were admitted to the hospital. Acceptable agreement was achieved in 18 of the 21 (86%) past medical history and current medication findings, none of the 10 physical examination variables, and three of the 13 (23%) ECG interpretation variables. There was moderate agreement (Spearman correlation coefficient, r = 0.40) between clinicians on the patient's probability of 30-day death or serious cardiac outcome, although as the probability increased, there was less agreement.

CONCLUSIONS

Acceptable agreement between raters was more commonly achieved with historical rather than physical examination or ECG interpretation variables. Clinicians had moderate agreement in assessing the patient's overall risk for a serious outcome at 30 days. Future development of clinical prediction models in older adults with syncope should account for variability of assessments between raters and consider the use of objective clinical variables.

Poor Outcomes After Emergency Department Discharge of the Elderly: A Case-Control Study

STUDY OBJECTIVE

The emergency department (ED) is an inherently high-risk setting. Our objective is to identify the factors associated with the combined poor outcome of either death or an ICU admission shortly after ED discharge in older adults.

METHODS

We conducted chart review of 600 ED visit records among adults older than 65 years that resulted in discharge from any of 13 hospitals within an integrated health system in 2009 to 2010. We randomly chose 300 patients who experienced the combined outcome within 7 days of discharge and matched case patients to controls who did not experience the outcome. Two emergency physicians blinded to the outcome reviewed the records and identified whether a number of characteristics were present. Predictors of the outcome were identified with conditional logistic regression.

RESULTS

Of 1,442,594 ED visits to Kaiser Permanente Southern California in 2009 to 2010, 300 unique cases and 300 unique control records were randomly abstracted. Characteristics associated with the combined poor outcome included cognitive impairment (adjusted odds ratio [AOR] 2.10; 95% confidence interval [CI] 1.19 to 3.56), disposition plan change (AOR 2.71; 95% CI 1.50 to 4.89), systolic blood pressure less than 120 mm Hg (AOR 1.48; 95% CI 1.00 to 2.20), and pulse rate greater than 90 beats/min (AOR 1.66; 95% CI 1.02 to 2.71).

CONCLUSION

We found that older patients discharged from the ED with a change in disposition from "admit" to "discharge," cognitive impairment, systolic blood pressure less than 120 mm Hg, and pulse rate greater than 90 beats/min were at increased risk of death or ICU admission shortly after discharge. Increased awareness of these high-risk characteristics may improve ED disposition decisionmaking.

Effect of Uncontrolled Diabetes on Outcomes After Cystectomy in Patients With Bladder Cancer: A Population-Based Study

BACKGROUND

We evaluated the complications, mortality, hospital length of stay (LOS), and cost for patients with diabetes undergoing radical cystectomy (RC).

MATERIALS AND METHODS

Data were extracted from the National (Nationwide) Inpatient Sample for 2001 to 2012 using the "International Classification of Diseases, Ninth Revision, Clinical Modification" codes for patients with uncontrolled diabetes (UD) (patients with diabetes receiving treatment that did not keep the blood glucose at acceptable levels) and controlled diabetes (CD) (patients with diabetes not otherwise stated as uncontrolled) who had undergone RC. χ² and Wilcoxon rank sum tests and multivariable regression analysis were used for statistics. The LOS and cost are presented as the median and interquartile range.

RESULTS

In the present study, 989 patients had UD, 15,693 CD, and 73,603 had no diabetes (ND). Postoperative complications were significantly more common in the UD group (73%) than in the CD (51%) and ND (52%) groups (P < .0001). On multivariable analysis, the UD group were more likely than the CD group to have any complication (odds ratio [OR], 2.3; 95% confidence interval [CI], 2.0-2.7), including renal (OR, 2.1; 95% CI, 1.8-2.4) and infectious (OR, 2.7; 95% CI, 2.3-3.1) complications. Patients with UD were also 4.3 times (95% CI, 3.1-5.8) more likely to die after surgery than were patients with CD. The ND group was slightly more likely than the CD group to experience any complication (OR, 1.13; 95% CI, 1.09-1.17) and death (OR, 1.6; 95% CI, 1.4-1.8). The LOS and cost for UD patients were greater than for CD patients. On multivariable analysis, UD patients had a 30% increase in LOS and 23% increase in cost (P < .0001).

CONCLUSION

The findings from the present study have demonstrated an increase in post-RC complications rates, hospital mortality, and hospital resource usage for patients with UD undergoing RC. UD might be a modifiable preoperative risk factor for post-RC morbidity and mortality. Further studies are needed to validate this association.

SEX, LIES AND SELF-REPORTED COUNTS: BAYESIAN MIXTURE MODELS FOR HEAPING IN LONGITUDINAL COUNT DATA VIA BIRTH-DEATH PROCESSES

Surveys often ask respondents to report non-negative counts, but respondents may misremember or round to a nearby multiple of 5 or 10. This phenomenon is called heaping, and the error inherent in heaped self-reported numbers can bias estimation. Heaped data may be collected cross-sectionally or longitudinally and there may be covariates that complicate the inferential task. Heaping is a well-known issue in many survey settings, and inference for heaped data is an important statistical problem. We propose a novel reporting distribution whose underlying parameters are readily interpretable as rates of misremembering and rounding. The process accommodates a variety of heaping grids and allows for quasi-heaping to values nearly but not equal to heaping multiples. We present a Bayesian hierarchical model for longitudinal samples with covariates to infer both the unobserved true distribution of counts and the parameters that control the heaping process. Finally, we apply our methods to longitudinal self-reported counts of sex partners in a study of high-risk behavior in HIV-positive youth.

Complication rates in patients with uncontrolled diabetes undergoing radical cystectomy: A population-based study

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Background: Radical cystectomy is known to be associated with a relatively high incidence of postoperative morbidity and mortality. We evaluated the complication rates of a population-based cohort of patients with uncontrolled diabetes who underwent radical cystectomy. Methods: The data for this analysis was captured from the NIS (Nationwide Inpatient Sample) 2002-2009. Among patients who underwent radical cystectomy (ICD-9 diagnosis code 188.x and 57.71), we selected those with uncontrolled diabetes, which is defined by the billing physician (ICD-9 diagnosis code 250.02) and compared to patients without diabetes. We also identified postoperative complications. Patient socio-demographic characteristics, principal and secondary diagnoses, principal and secondary procedures, comorbid diseases, disposition of patient at discharge, hospital length of stay, and hospital cost for our analysis. A chi-square test was employed for categorical variables and Student’s t-test for continuous variables. A multivariable logistic regression analysis was also employed with computing OR and 95% CI. P<0.05 was considered statistically significant. Results: There were significant differences in the postoperative outcomes between groups. In the univariable analysis, patients with uncontrolled diabetes were more likely to have complications (OR=3.21; 95%CI= 2.59-4.00) including infectious complications (OR=2.46; 95%CI= 1.98-3.06) and were more likely to die during the index hospitalization (OR=3.27; 95%CI= 1.41-7.61). Hospital resource utilization was also significantly greater in patients with uncontrolled diabetes. Mean length of stay in this group was 17.3 days compared to 11.4 days in non-diabetic group (P=0.0007); total hospital cost was, respectively, $47,960 and $32,422 (P=0.0009). Conclusions: This study demonstrates a significant association between uncontrolled diabetes and in-hospital post-cystectomy complications, mortality, and hospital resource utilization. This study highlights the recognition of uncontrolled diabetes as a potential modifiable risk factor for patients undergoing cystectomy.

Performance of partial cystectomy in the United States from 2001 to 2010: trends and comparative outcomes

INTRODUCTION

To investigate the trends in the performance of radical cystectomy (RC) versus partial cystectomy (PC) in the United States over the past 10 years and compare postoperative outcomes between two procedures.

MATERIALS AND METHODS

The data was captured from the Nationwide Inpatient Sample (NIS) 2001-2010 using the appropriate ICD-9-CM diagnosis and procedure codes. Patient sociodemographics, comorbidities and in-hospital complications after PC and RC were compared, taking into account some hospital characteristics. A chi-square analysis including a Cochran-Armitage trend test and a multivariable logistic regression analysis were employed.

RESULTS

RC rate increased from 84.8% in 2001 to 90.3% in 2010, while PC decreased from 15.2% to 9.7% (p < 0.0001). PC patients were older than their RC counterparts (72.1 ± 11.3 versus 68.6 ± 10.1 years; p < 0.0001), had higher prevalence of major comorbidities, but decreased rate of postoperative complications overall (21.3% versus 38.6%; p < 0.001). The greatest rates of PC utilization were found in the Northeast and South (12.8% and 12.7%). The frequency of PC was 18.9% in non-teaching hospitals compared to 9.0% in teaching hospitals (p < 0.0001). In multivariate analysis, females, octogenarians, patients with hypertension and obesity, and patients in non-teaching and rural hospitals were more likely to receive PC.

CONCLUSIONS

Despite the potential advantages in cancer control offered by RC, PC is being performed more frequently on the elderly, female patients, patients with hypertension and obesity, in non-teaching and rural hospitals, and in certain United States geographic regions, which can be partially explained by disparities in access to high volume cancer centers.

Determining minimum food intake amounts for diet diversity scores to maximize associations with nutrient adequacy: an analysis of schoolchildren's diets in rural Kenya

OBJECTIVE

To explore multiple methods of calculating diet diversity scores (DDS) to maximize associations with predicted dietary micronutrient adequacy among schoolchildren in rural Kenya.

DESIGN

Up to three 24 h recall interviews were administered for each child for a total of 1544 d of intake from all schoolchildren. Daily amounts of food consumed were assigned to one of eight food groups. Five DDS were developed based on various minimum intake amounts from each food group: (i) 1 g; (ii) 15 g; (iii) a variable minimum based on the content of a target nutrient for each group; (iv) the median intake level for each group; and (v) the 90th percentile intake level for each group. A diet was assigned 1 point towards the daily DDS if the food group intake was above the defined minimum level. Five scores were calculated for each child, and bivariate longitudinal random-effects models were used to assess the correlation between each DDS and the mean probability of adequacy for fourteen nutrients.

SETTING

Embu District, Kenya.

SUBJECTS

Schoolchildren (n 529), mean age 7·00 (sd 1·41) years.

RESULTS

Only DDS based on a 15 g minimum and DDS based on nutrient content were significantly associated with mean probability of adequacy after adjusting for energy intake (0·21 and 0·41, respectively).

CONCLUSIONS

A DDS using minimum intakes based on nutrients contributed by a food group best predicted nutrient adequacy in this population. These analyses contribute to the continued search for simpler and more valid dietary quality indicators among low-income nations.

A cluster randomised controlled effectiveness trial evaluating perinatal home visiting among South African mothers/infants

BACKGROUND

Interventions are needed to reduce poor perinatal health. We trained community health workers (CHWs) as home visitors to address maternal/infant risks.

METHODS

In a cluster randomised controlled trial in Cape Town townships, neighbourhoods were randomised within matched pairs to 1) the control, healthcare at clinics (n = 12 neighbourhoods; n = 594 women), or 2) a home visiting intervention by CBW trained in cognitive-behavioural strategies to address health risks (by the Philani Maternal, Child Health and Nutrition Programme), in addition to clinic care (n = 12 neighbourhoods; n = 644 women). Participants were assessed during pregnancy (2% refusal) and 92% were reassessed at two weeks post-birth, 88% at six months and 84% at 18 months later. We analysed 32 measures of maternal/infant well-being over the 18 month follow-up period using longitudinal random effects regressions. A binomial test for correlated outcomes evaluated overall effectiveness over time. The 18 month post-birth assessment outcomes also were examined alone and as a function of the number of home visits received.

RESULTS

Benefits were found on 7 of 32 measures of outcomes, resulting in significant overall benefits for the intervention compared to the control when using the binomial test (p = 0.008); nevertheless, no effects were observed when only the 18 month outcomes were analyzed. Benefits on individual outcomes were related to the number of home visits received. Among women living with HIV, intervention mothers were more likely to implement the PMTCT regimens, use condoms during all sexual episodes (OR = 1.25; p = 0.014), have infants with healthy weight-for-age measurements (OR = 1.42; p = 0.045), height-for-age measurements (OR = 1.13, p<0.001), breastfeed exclusively for six months (OR = 3.59; p<0.001), and breastfeed longer (OR = 3.08; p<0.001). Number of visits was positively associated with infant birth weight ≥2500 grams (OR = 1.07; p = 0.012), healthy head-circumference-for-age measurements at 6 months (OR = 1.09, p = 0.017), and improved cognitive development at 18 months (OR = 1.02, p = 0.048).

CONCLUSIONS

Home visits to neighbourhood mothers by CHWs may be a feasible strategy for enhancing maternal/child outcomes. However, visits likely must extend over several years for persistent benefits.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00996528.

Sex on demand: geosocial networking phone apps and risk of sexually transmitted infections among a cross-sectional sample of men who have sex with men in Los Angeles County

BACKGROUND

Geosocial networking applications (GSN apps) used for meeting sexual partners have become increasingly popular with men who have sex with men (MSM) since 2009. The current study aimed to determine if self-identified HIV-negative, MSM clinic attendees who used GSN apps have an increased incidence of sexually transmitted infections (STI) compared to self-identified HIV-negative, MSM attendees who met sexual partners via in-person venues, such as bars or clubs or through MSM-specific hook-up websites.

METHODS

Data were collected between August 2011 and January 2013 on all self-identified HIV-negative, MSM clients visiting the L.A. Gay & Lesbian Center for STI screening. A total of 7184 individuals tested for STIs and self-reported behaviours on drug use and social networking methods to meet sexual partners. Multivariate logistic regression models were used to analyse the results.

RESULTS

Individuals who used GSN apps for meeting sexual partners had greater odds of testing positive for gonorrhoea (OR: 1.25; 95% CI 1.06 to 1.48) and for chlamydia (OR: 1.37; 95% CI 1.13 to 1.65) compared to individuals who met partners through in-person methods only. There were no significant differences in syphilis and HIV incidence between those who met partners via in-person venues only, on the internet or through GSN apps.

CONCLUSIONS

The present study concludes that sexual health clinic MSM attendees who are meeting on GSN apps are at greater risk for gonorrhoea and chlamydia than MSM attendees who meet in-person or on the internet. Future interventions should explore the use of these novel technologies for testing promotion, prevention and education.

The slippery slope: lubricant use and rectal sexually transmitted infections: a newly identified risk

BACKGROUND

Use of lubricant products is extremely common during receptive anal intercourse (RAI) yet has not been assessed as a risk for acquisition of sexually transmitted infections (STIs).

METHODS

Between 2006 and 2008, a rectal health and behavior study was conducted in Baltimore and Los Angeles as part of the University of California, Los Angeles Microbicide Development Program (NIAID IPCP# #0606414). Participants completed questionnaires, and rectal swabs were tested for Neisseria gonorrhoeae and Chlamydia trachomatis with the Aptima Combo 2 assay, and blood was tested for syphilis (for RPR and TPHA with titer) and HIV. Of those reporting lubricant use and RAI, STI results were available for 380 participants. Univariate and multivariate regressions assessed associations of lubricant use in the past month during RAI with prevalent STIs.

RESULTS

Consistent lubricant use during RAI in the past month was reported by 36% (137/380) of participants. Consistent past month lubricant users had a higher prevalence of STI than inconsistent users (9.5% vs. 2.9%; P = 0.006). In a multivariable logistic regression model, testing positive for STI was associated with consistent use of lubricant during RAI in the past month (adjusted odds ratio: 2.98 95% confidence interval: 1.09, 8.15) after controlling for age, gender, study location, HIV status, and numbers of RAI partners in the past month.

CONCLUSIONS

Findings suggest some lubricant products may increase vulnerability to STIs. Because of wide use of lubricants and their potential as carrier vehicles for microbicides, further research is essential to clarify if lubricant use poses a public health risk.

Is emergency department crowding associated with increased "bounceback" admissions?

OBJECTIVE

Emergency department (ED) crowding is linked with poor quality of care and worse outcomes, including higher mortality. With the growing emphasis on hospital performance measures, there is additional concern whether inadequate care during crowded periods increases a patient's likelihood of subsequent inpatient admission. We sought to determine if ED crowding during the index visit was associated with these "bounceback" admissions.

METHODS

We used comprehensive, nonpublic, statewide ED and inpatient discharge data from the California Office of Statewide Health Planning and Development from 2007 to identify index outpatient ED visits and bounceback admissions within 7 days. We further used ambulance diversion data collected from California local emergency medical services agencies to identify crowded days using intrahospital daily diversion hour quartiles. Using a hierarchical logistic regression model, we then determined if patients visiting on crowded days were more likely to have a subsequent bounceback admission.

RESULTS

We analyzed 3,368,527 index visits across 202 hospitals, of which 596,471 (17.7%) observations were on crowded days. We found no association between ED crowding and bounceback admissions. This lack of relationship persisted in both a discrete (high/low) model (OR, 1.01; 95% CI, 0.99, 1.02) and a secondary model using ambulance diversion hours as a continuous predictor (OR, 1.00; 95% CI, 1.00, 1.00).

CONCLUSIONS

Crowding as measured by ambulance diversion does not have an association with hospitalization within 7 days of an ED visit discharge. Therefore, bounceback admission may be a poor measure of delayed or worsened quality of care due to crowding.

Concurrent life-course trajectories of employment and marijuana-use: exploring interdependence of longitudinal outcomes

This study analyzes data on 7661 individuals who participated in the 1979 National Longitudinal Survey of Youth (NLSY79) to estimate trajectories of employment and marijuana-use over a 17-year period. Bivariate random intercept and slope modeling is applied to examine concurrently the cross-correlation between the two concurrent longitudinal trajectories from age 23 to 39. Parameter estimates indicate baseline level (at age 23) of employment to be negatively correlated with marijuana, suggesting marijuana-use is associated with lower workforce productivity at age 23. The longitudinal employment slope is positively correlated with employment intercept for both males and females, indicating that survey participants with higher levels of employment at age 23 are more likely to have a positive impact on employment trajectory over time. For males, however, the employment slope is also significantly correlated with marijuana intercept (r=-0.07), indicating marijuana-use in early adulthood may uniquely lower workforce productivity over age.

Seroadaptation in a sample of very poor Los Angeles area men who have sex with men

Data from 635 very poor men who have sex with men (MSM) were used to identify seroadaptation with 1,102 male partners reported between 2005 and 2007 in Los Angeles as part of the Sexual Acquisition and Transmission of HIV Cooperative Agreement Program. The mean age of the sample was 41.7 years; 53 % had experienced homelessness in the past year. Condoms were reported in 51 % of sexual events involving anal intercourse. HIV seroconcordance was reported in 41 % of sexual partnerships among HIV-positive participants. HIV-positive men were more likely to have oral-only or unprotected receptive anal intercourse and less likely to have unprotected insertive anal intercourse with HIV-negative or unknown partners compared to HIV-positive partners. Even in the face of poverty, HIV-positive MSM report mitigating risks of HIV-transmission though seroadaptation in the context of modest rates of condom use.

Outcomes of home visits for pregnant mothers and their infants: a cluster randomized controlled trial

OBJECTIVE

To evaluate the effect of home visits by community health workers (CHWs) on maternal and infant well being from pregnancy through the first 6 months of life for women living with HIV (WLH) and all neighborhood mothers.

DESIGN AND METHODS

In a cluster randomized controlled trial in Cape Town townships, neighborhoods were randomized within matched pairs to either standard care, comprehensive healthcare at clinics (n=12 neighborhoods; n=169 WLH; n=594 total mothers); or Philani Intervention Program, home visits by CHWs in addition to standard care (PIP; n=12 neighborhoods; n=185 WLH; n=644 total mothers). Participants were assessed during pregnancy (2% refusal) and reassessed at 1 week (92%) and 6 months (88%) postbirth. We analyzed PIP's effect on 28 measures of maternal and infant well being among WLH and among all mothers using random effects regression models. For each group, PIP's overall effectiveness was evaluated using a binomial test for correlated outcomes.

RESULTS

Significant overall benefits were found in PIP compared to standard care among WLH and among all participants. Secondarily, compared to standard care, PIP WLH were more likely to complete tasks to prevent vertical transmission, use one feeding method for 6 months, avoid birth-related medical complications, and have infants with healthy height-for-age measurements. Among all mothers, compared to standard care, PIP mothers were more likely to use condoms consistently, breastfeed exclusively for 6 months, and have infants with healthy height-for-age measurements.

CONCLUSION

PIP is a model for countries facing significant reductions in HIV funding whose families face multiple health risks.

Factors associated with short-term bounce-back admissions after emergency department discharge

STUDY OBJECTIVE

Hospitalizations that occur shortly after emergency department (ED) discharge may reveal opportunities to improve ED or follow-up care. There currently is limited, population-level information about such events. We identify hospital- and visit-level predictors of bounce-back admissions, defined as 7-day unscheduled hospital admissions after ED discharge.

METHODS

Using the California Office of Statewide Health Planning and Development files, we conducted a retrospective cohort analysis of adult (aged >18 years) ED visits resulting in discharge in 2007. Candidate predictors included index hospital structural characteristics such as ownership, teaching affiliation, trauma status, and index ED size, along with index visit patient characteristics of demographic information, day of service, against medical advice or eloped disposition, insurance, and ED primary discharge diagnosis. We fit a multivariable, hierarchic logistic regression to account for clustering of ED visits by hospitals.

RESULTS

The study cohort contained a total of 5,035,833 visits to 288 facilities in 2007. Bounce-back admission within 7 days occurred in 130,526 (2.6%) visits and was associated with Medicaid (odds ratio [OR] 1.42; 95% confidence interval [CI] 1.40 to 1.45) or Medicare insurance (OR 1.53; 95% CI 1.50 to 1.55) and a disposition of leaving against medical advice or before the evaluation was complete (OR 1.90; 95% CI 1.89 to 2.0). The 3 most common age-adjusted index ED discharge diagnoses associated with a bounce-back admission were chronic renal disease, not end stage (OR 3.3; 95% CI 2.8 to 3.8), end-stage renal disease (OR 2.9; 95% CI 2.4 to 3.6), and congestive heart failure (OR 2.5; 95% CI 2.3 to 2.6). Hospital characteristics associated with a higher bounce-back admission rate were for-profit status (OR 1.2; 95% CI 1.1 to 1.3) and teaching affiliation (OR 1.2; 95% CI 1.0 to 1.3).

CONCLUSION

We found 2.6% of discharged patients from California EDs to have a bounce-back admission within 7 days. We identified vulnerable populations, such as the very old and the use of Medicaid insurance, and chronic or end-stage renal disease as being especially at risk. Our findings suggest that quality improvement efforts focus on high-risk individuals and that the disposition plan of patients consider vulnerable populations.

Intimate partner violence and anal intercourse in young adult heterosexual relationships

CONTEXT

Although intimate partner violence and anal intercourse are common in young adult relationships, few studies have examined whether these behaviors are associated with each other.

METHODS

Data from 6,280 women aged 18-28 who took part in Wave 3 of the National Longitudinal Study of Adolescent Health were used to examine the association between physical and sexual intimate partner violence and anal intercourse in 10,462 relationships. Multivariate hierarchical random effects models were used to adjust for the clustered survey design and for the multiple relationships reported per participant.

RESULTS

Physical violence occurred in 29% of relationships, sexual violence in 11% and anal intercourse in 14%. The odds that a couple had had anal intercourse were greater among relationships that included physical violence perpetrated by both partners or only by the woman than among nonviolent relationships (odds ratios, 1.7 and 1.9, respectively). The odds of anal intercourse were also elevated among sexually abusive relationships, although only if the woman was the sole victim or the sole perpetrator (1.3 and 2.0, respectively). In relationships that included anal intercourse, the odds of condom use were lower if the woman was a victim of physical violence than if no violence occurred (0.2). Sexual violence was not associated with condom use.

CONCLUSION

Women in physically violent relationships may be at increased risk for STDs because of their elevated exposure to unprotected anal intercourse. More information on the context surrounding anal intercourse and intimate partner violence is needed to understand the nuances of this association.

Child center closures: Does nonprofit status provide a comparative advantage?

Reliable access to dependable, high quality childcare services is a vital concern for large numbers of American families. The childcare industry consists of private nonprofit, private for-profit, and governmental providers that differ along many dimensions, including quality, clientele served, and organizational stability. Nonprofit providers are theorized to provide higher quality services given comparative tax advantages, higher levels of consumer trust, and management by mission driven entrepreneurs. This study examines the influence of ownership structure, defined as nonprofit, for-profit sole proprietors, for-profit companies, and governmental centers, on organizational instability, defined as childcare center closures. Using a cross sectional data set of 15724 childcare licenses in California for 2007, we model the predicted closures of childcare centers as a function of ownership structure as well as center age and capacity. Findings indicate that for small centers (capacity of 30 or less) nonprofits are more likely to close, but for larger centers (capacity 30+) nonprofits are less likely to close. This suggests that the comparative advantages available for nonprofit organizations may be better utilized by larger centers than by small centers. We consider the implications of our findings for parents, practitioners, and social policy.

Acceptability of potential rectal microbicide delivery systems for HIV prevention: a randomized crossover trial

We assessed the acceptability of three of over-the-counter products representative of potential rectal microbicide (RM) delivery systems. From 2009 to 2010, 117 HIV-uninfected males (79 %) and females (21 %) who engage in receptive anal intercourse participated in a 6-week randomized crossover acceptability trial. Participants received each of three products (enema, lubricant-filled applicator, suppository) every 2 weeks in a randomized sequence. CASI and T-ACASI scales assessed product acceptability via Likert responses. Factor analysis was used to identify underlying factors measured by each scale. Random effects models were fit to examine age and gender effects on product acceptability. Three underlying factors were identified: Satisfaction with Product Use, Sexual Pleasure, and Ease of Product Use. For acceptability, the applicator ranked highest; however, differences between product acceptability scores were greatest among females and younger participants. These findings indicate that RM delivery systems impact their acceptability and should be considered early in RM development to enhance potential use.

California hospitals serving large minority populations were more likely than others to employ ambulance diversion

It is well documented that racial and ethnic minority populations disproportionately use hospital emergency departments for safety-net care. But what is not known is whether emergency department crowding is disproportionately affecting minority populations and potentially aggravating existing health care disparities, including poorer outcomes for minorities. We examined ambulance diversion, a proxy measure for crowding, at 202 California hospitals. We found that hospitals serving large minority populations were more likely to divert ambulances than were hospitals with a lower proportion of minorities, even when controlling for hospital ownership, emergency department capacity, and other hospital demographic and structural factors. These findings suggest that establishing more-uniform criteria to regulate diversion may help reduce disparities in access to emergency care.

Effect of emergency department crowding on outcomes of admitted patients

STUDY OBJECTIVE

Emergency department (ED) crowding is a prevalent health delivery problem and may adversely affect the outcomes of patients requiring admission. We assess the association of ED crowding with subsequent outcomes in a general population of hospitalized patients.

METHODS

We performed a retrospective cohort analysis of patients admitted in 2007 through the EDs of nonfederal, acute care hospitals in California. The primary outcome was inpatient mortality. Secondary outcomes included hospital length of stay and costs. ED crowding was established by the proxy measure of ambulance diversion hours on the day of admission. To control for hospital-level confounders of ambulance diversion, we defined periods of high ED crowding as those days within the top quartile of diversion hours for a specific facility. Hierarchic regression models controlled for demographics, time variables, patient comorbidities, primary diagnosis, and hospital fixed effects. We used bootstrap sampling to estimate excess outcomes attributable to ED crowding.

RESULTS

We studied 995,379 ED visits resulting in admission to 187 hospitals. Patients who were admitted on days with high ED crowding experienced 5% greater odds of inpatient death (95% confidence interval [CI] 2% to 8%), 0.8% longer hospital length of stay (95% CI 0.5% to 1%), and 1% increased costs per admission (95% CI 0.7% to 2%). Excess outcomes attributable to periods of high ED crowding included 300 inpatient deaths (95% CI 200 to 500 inpatient deaths), 6,200 hospital days (95% CI 2,800 to 8,900 hospital days), and $17 million (95% CI $11 to $23 million) in costs.

CONCLUSION

Periods of high ED crowding were associated with increased inpatient mortality and modest increases in length of stay and costs for admitted patients.