Pre-COVID-19 hospital quality and hospital response to COVID-19: examining associations between risk-adjusted mortality for patients hospitalised with COVID-19 and pre-COVID-19 hospital quality

OBJECTIVES

The extent to which care quality influenced outcomes for patients hospitalised with COVID-19 is unknown. Our objective was to determine if prepandemic hospital quality is associated with mortality among Medicare patients hospitalised with COVID-19.

DESIGN

This is a retrospective observational study. We calculated hospital-level risk-standardised in-hospital and 30-day mortality rates (risk-standardised mortality rates, RSMRs) for patients hospitalised with COVID-19, and correlation coefficients between RSMRs and pre-COVID-19 hospital quality, overall and stratified by hospital characteristics.

SETTING

Short-term acute care hospitals and critical access hospitals in the USA.

PARTICIPANTS

Hospitalised Medicare beneficiaries (Fee-For-Service and Medicare Advantage) age 65 and older hospitalised with COVID-19, discharged between 1 April 2020 and 30 September 2021.

INTERVENTION/EXPOSURE

Pre-COVID-19 hospital quality.

OUTCOMES

Risk-standardised COVID-19 in-hospital and 30-day mortality rates (RSMRs).

RESULTS

In-hospital (n=4256) RSMRs for Medicare patients hospitalised with COVID-19 (April 2020-September 2021) ranged from 4.5% to 59.9% (median 18.2%; IQR 14.7%-23.7%); 30-day RSMRs ranged from 12.9% to 56.2% (IQR 24.6%-30.6%). COVID-19 RSMRs were negatively correlated with star rating summary scores (in-hospital correlation coefficient -0.41, p<0.0001; 30 days -0.38, p<0.0001). Correlations with in-hospital RSMRs were strongest for patient experience (-0.39, p<0.0001) and timely and effective care (-0.30, p<0.0001) group scores; 30-day RSMRs were strongest for patient experience (-0.34, p<0.0001) and mortality (-0.33, p<0.0001) groups. Patients admitted to 1-star hospitals had higher odds of mortality (in-hospital OR 1.87, 95% CI 1.83 to 1.91; 30-day OR 1.46, 95% CI 1.43 to 1.48) compared with 5-star hospitals. If all hospitals performed like an average 5-star hospital, we estimate 38 000 fewer COVID-19-related deaths would have occurred between April 2020 and September 2021.

CONCLUSIONS

Hospitals with better prepandemic quality may have care structures and processes that allowed for better care delivery and outcomes during the COVID-19 pandemic. Understanding the relationship between pre-COVID-19 hospital quality and COVID-19 outcomes will allow policy-makers and hospitals better prepare for future public health emergencies.

Incorporating Present-on-Admission Indicators in Medicare Claims to Inform Hospital Quality Measure Risk Adjustment Models

Importance

Present-on-admission (POA) indicators in administrative claims data allow researchers to distinguish between preexisting conditions and those acquired during a hospital stay. The impact of adding POA information to claims-based measures of hospital quality has not yet been investigated to better understand patient underlying risk factors in the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision setting.

Objective

To assess POA indicator use on Medicare claims and to assess the hospital- and patient-level outcomes associated with incorporating POA indicators in identifying risk factors for publicly reported outcome measures used by the Centers for Medicare & Medicaid Services (CMS).

Design, Setting, and Participants

This comparative effectiveness study used national CMS claims data between July 1, 2015, and June 30, 2018. Six hospital quality measures assessing readmission and mortality outcomes were modified to include POA indicators in risk adjustment models. The models using POA were then compared with models using the existing complications-of-care algorithm to evaluate changes in risk model performance. Patient claims data were included for all Medicare fee-for-service and Veterans Administration beneficiaries aged 65 years or older with inpatient hospitalizations for acute myocardial infarction, heart failure, or pneumonia within the measurement period. Data were analyzed between September 2019 and March 2020.

Main Outcomes and Measures

Changes in patient-level (C statistics) and hospital-level (quintile shifts in risk-standardized outcome rates) model performance after including POA indicators in risk adjustment.

Results

Data from a total of 6 027 988 index admissions were included for analysis, ranging from 491 366 admissions (269 209 [54.8%] men; mean [SD] age, 78.2 [8.3] years) for the acute myocardial infarction mortality outcome measure to 1 395 870 admissions (677 158 [48.5%] men; mean [SD] age, 80.3 [8.7] years) for the pneumonia readmission measure. Use of POA indicators was associated with improvements in risk adjustment model performance, particularly for mortality measures (eg, the C statistic increased from 0.728 [95% CI, 0.726-0.730] to 0.774 [95% CI, 0.773-0.776] when incorporating POA indicators into the acute myocardial infarction mortality measure).

Conclusions and Relevance

The findings of this quality improvement study suggest that leveraging POA indicators in the risk adjustment methodology for hospital quality outcome measures may help to more fully capture patients' risk factors and improve overall model performance. Incorporating POA indicators does not require extra effort on the part of hospitals and would be easy to implement in publicly reported quality outcome measures.

Prospective, randomized, double-blind, placebo-controlled evaluation of the Pharmacokinetics, Safety and Efficacy of Recombinant Antithrombin Versus Placebo in Preterm Preeclampsia

BACKGROUND

Despite expectant management, preeclampsia remote from term usually results in preterm delivery. Antithrombin, which displays antiinflammatory and anticoagulant properties, may have a therapeutic role in treating preterm preeclampsia, a disorder characterized by endothelial dysfunction, inflammation, and activation of the coagulation system.

OBJECTIVE

This randomized, placebo-controlled clinical trial aimed to evaluate whether intravenous recombinant human antithrombin could prolong gestation and therefore improve maternal and fetal outcomes.

STUDY DESIGN

We performed a double-blind, placebo-controlled trial at 23 hospitals. Women were eligible if they had a singleton pregnancy, early-onset or superimposed preeclampsia at 23 0/7 to 30 0/7 weeks' gestation, and planned expectant management. In addition to standard therapy, patients were randomized to receive either recombinant human antithrombin 250 mg loading dose followed by a continuous infusion of 2000 mg per 24 hours or an identical saline infusion until delivery. The primary outcome was days gained from randomization until delivery. The secondary outcome was composite neonatal morbidity score. A total of 120 women were randomized.

RESULTS

There was no difference in median gestational age at enrollment (27.3 weeks' gestation for the recombinant human antithrombin group [range, 23.1-30.0] and 27.6 weeks' gestation for the placebo group [range, 23.0-30.0]; P=.67). There were no differences in median increase in days gained (5.0 in the recombinant human antithrombin group [range, 0-75] and 6.0 for the placebo group [range, 0-85]; P=.95). There were no differences between groups in composite neonatal morbidity scores or in maternal complications. No safety issues related to recombinant human antithrombin were noted in this study, despite the achievement of supraphysiological antithrombin concentrations.

CONCLUSION

The administration of recombinant human antithrombin in preterm preeclampsia neither prolonged pregnancy nor improved neonatal or maternal outcomes.

Development and Validation of a Risk Prediction Model for Cesarean Delivery After Labor Induction

Objective: The goal of the study was to develop and validate a prediction model for cesarean delivery after labor induction that included factors known before the start of induction, unlike prior studies that focused on characteristics at the time of induction. Materials and Methods: Using 17,370 term labor inductions without documented medical indications occurring at 14 U.S. hospitals, 2007-2012, we created and evaluated a model predicting cesarean delivery. We assessed model calibration and discrimination, and we used bootstrapping for internal validation. We externally validated the model by using 2122 labor inductions from a hospital not included in the development cohort. Results: The model contained eight variables-gestational age, maternal race, parity, maternal age, obesity, fibroids, excessive fetal growth, and history of herpes-and was well calibrated with good risk stratification at the extremes of predicted probability. The model had an area under the curve (AUC) for the receiver operating characteristic curve of 0.82 (95% confidence interval 0.81-0.83), and it performed well on internal validation. The AUC in the external validation cohort was 0.82. Conclusion: This prediction model can help providers estimate a woman's risk of cesarean delivery when planning a labor induction.

Development and Testing of Improved Models to Predict Payment Using Centers for Medicare & Medicaid Services Claims Data

Importance

Predicting payments for particular conditions or populations is essential for research, benchmarking, public reporting, and calculations for population-based programs. Centers for Medicare & Medicaid Services (CMS) models often group codes into disease categories, but using single, rather than grouped, diagnostic codes and leveraging present on admission (POA) codes may enhance these models.

Objective

To determine whether changes to the candidate variables in CMS models would improve risk models predicting patient total payment within 30 days of hospitalization for acute myocardial infarction (AMI), heart failure (HF), and pneumonia.

Design, Setting, and Participants

This comparative effectiveness research study used data from Medicare fee-for-service hospitalizations for AMI, HF, and pneumonia at acute care hospitals from July 1, 2013, through September 30, 2015. Payments across multiple care settings, services, and supplies were included and adjusted for geographic and policy variations, corrected for inflation, and winsorized. The same data source was used but varied for the candidate variables and their selection, and the method used by CMS for public reporting that used grouped codes was compared with variations that used POA codes and single diagnostic codes. Combinations of use of POA codes, separation of index admission diagnoses from those in the previous 12 months, and use of individual International Classification of Diseases, Ninth Revision, Clinical Modification codes instead of grouped diagnostic categories were tested. Data analysis was performed from December 4, 2017, to June 10, 2019.

Main Outcomes and Measures

The models' goodness of fit was compared using root mean square error (RMSE) and the McFadden pseudo R2.

Results

Among the 1 943 049 total hospitalizations of the study participants, 343 116 admissions were for AMI (52.5% male; 37.4% aged ≤74 years), 677 044 for HF (45.5% male; 25.9% aged ≤74 years), and 922 889 for pneumonia (46.4% male; 28.2% aged ≤74 years). The mean (SD) 30-day payment was $23 103 ($18 221) for AMI, $16 365 ($12 527) for HF, and $17 097 ($12 087) for pneumonia. Each incremental model change improved the pseudo R2 and RMSE. Incorporating all 3 changes improved the pseudo R2 of the patient-level models from 0.077 to 0.129 for AMI, from 0.042 to 0.129 for HF, and from 0.114 to 0.237 for pneumonia. Parallel improvements in RMSE were found for all 3 conditions.

Conclusions and Relevance

Leveraging POA codes, separating index from previous diagnoses, and using single diagnostic codes improved payment models. Better models can potentially improve research, benchmarking, public reporting, and calculations for population-based programs.

Comparative Effectiveness of New Approaches to Improve Mortality Risk Models From Medicare Claims Data

IMPORTANCE

Risk adjustment models using claims-based data are central in evaluating health care performance. Although US Centers for Medicare & Medicaid Services (CMS) models apply well-vetted statistical approaches, recent changes in the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) coding system and advances in computational capabilities may provide an opportunity for enhancement.

OBJECTIVE

To examine whether changes using already available data would enhance risk models and yield greater discrimination in hospital-level performance measures.

DESIGN, SETTING, AND PARTICIPANTS

This comparative effectiveness study used ICD-9-CM codes from all Medicare fee-for-service beneficiary claims for hospitalizations for acute myocardial infarction (AMI), heart failure (HF), or pneumonia among patients 65 years and older from July 1, 2013, through September 30, 2015. Changes to current CMS mortality risk models were applied incrementally to patient-level models, and the best model was tested on hospital performance measures to model 30-day mortality. Analyses were conducted from April 19, 2018, to September 19, 2018.

MAIN OUTCOMES AND MEASURES

The main outcome was all-cause death within 30 days of hospitalization for AMI, HF, or pneumonia, examined using 3 changes to current CMS mortality risk models: (1) incorporating present on admission coding to better exclude potential complications of care, (2) separating index admission diagnoses from those of the 12-month history, and (3) using ungrouped ICD-9-CM codes.

RESULTS

There were 361 175 hospital admissions (mean [SD] age, 78.6 [8.4] years; 189 225 [52.4%] men) for AMI, 716 790 hospital admissions (mean [SD] age, 81.1 [8.4] years; 326 825 [45.6%] men) for HF, and 988 225 hospital admissions (mean [SD] age, 80.7 [8.6] years; 460 761 [46.6%] men) for pneumonia during the study; mean 30-day mortality rates were 13.8% for AMI, 12.1% for HF, and 16.1% for pneumonia. Each change to the models was associated with incremental gains in C statistics. The best model, incorporating all changes, was associated with significantly improved patient-level C statistics, from 0.720 to 0.826 for AMI, 0.685 to 0.776 for HF, and 0.715 to 0.804 for pneumonia. Compared with current CMS models, the best model produced wider predicted probabilities with better calibration and Brier scores. Hospital risk-standardized mortality rates had wider distributions, with more hospitals identified as good or bad performance outliers.

CONCLUSIONS AND RELEVANCE

Incorporating present on admission coding and using ungrouped index and historical ICD-9-CM codes were associated with improved patient-level and hospital-level risk models for mortality compared with the current CMS models for all 3 conditions.

Gene-Centric Analysis of Preeclampsia Identifies Maternal Association at PLEKHG1

The genetic susceptibility to preeclampsia, a pregnancy-specific complication with significant maternal and fetal morbidity, has been poorly characterized. To identify maternal genes associated with preeclampsia risk, we assembled 498 cases and 1864 controls of European ancestry from preeclampsia case-control collections in 5 different US sites (with additional matched population controls), genotyped samples on a cardiovascular gene-centric array composed of variants from ≈2000 genes selected based on prior genetic studies of cardiovascular and metabolic diseases and performed case-control genetic association analysis on 27 429 variants passing quality control. In silico replication testing of 9 lead signals with P<10-4 was performed in independent European samples from the SOPHIA (Study of Pregnancy Hypertension in Iowa) and Inova cohorts (212 cases, 456 controls). Multiethnic assessment of lead signals was then performed in samples of black (26 cases, 136 controls), Hispanic (132 cases, 468 controls), and East Asian (9 cases, 80 controls) ancestry. Multiethnic meta-analysis (877 cases, 3004 controls) revealed a study-wide statistically significant association of the rs9478812 variant in the pleiotropic PLEKHG1 gene (odds ratio, 1.40 [1.23-1.60]; Pmeta=5.90×10-7). The rs9478812 effect was even stronger in the subset of European cases with known early-onset preeclampsia (236 cases diagnosed <37 weeks, 1864 controls; odds ratio, 1.59 [1.27-1.98]; P=4.01×10-5). PLEKHG1 variants have previously been implicated in genome-wide association studies of blood pressure, body weight, and neurological disorders. Although larger studies are required to further define maternal preeclampsia heritability, this study identifies a novel maternal risk locus for further investigation.

Quantification characteristics of digital spiral analysis for understanding the relationship among tremor and clinical measures in persons with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is a degenerative neurological condition causing demyelination and neuronal loss. Tremor, a symptom of MS, is prevalent in 45.0-46.8% NARCOMS registrants. Although several tools to measure tremor exist, few outcomes are quantitative or regularly utilized clinically.

NEW METHOD

Introduction of a novel adaptation of the digital spiral drawing to find a quick, sensitive, and clinically useful technique, to predict tremor in persons with MS (pwMS). Digital spiral measures included: Segment Rate (SEGRT), Standard Deviation (SD) of Radial Velocity (VSD-R), SD of Tangential Velocity (VSD-T), SD of Overall Velocity (VSD-O), Mean Drawing Velocity (MNV-O) and Mean Pen Pressure Acceleration (MNA-P). Digital spiral measures were compared with the manual Archimedes Spiral (AS) drawing and the following clinical measures: Finger-Nose Test (FNT), presence of visually observed intention tremor (VOT), Nine-Hole Peg Test (NHPT), and Box and Block Test (BBT).

RESULTS

All clinical measures utilized demonstrated significant relationships with all digital variables, except VSD-R. The forward-stepwise regression revealed BBT accounted for the most variance, followed by SEGRT. Comparison with Existing Methods: SEGRT is more sensitive in detecting VOT and better for quantifying tremor than AS. BBT and SEGRT are optimal predictive measures for tremor.

CONCLUSIONS

SEGRT has stronger sensitivity and negative predictive value than AS in detecting VOT. All clinical measures (NHPT, FNT, BBT, and AS) were significantly associated with the digital variables (SEGRT, VSD-T, VSD-O, MNV-O, and MNA-P) except for VSD-R. After controlling for Patient Determined Disease Steps (PDDS), BBT and SEGRT are the best predictive measures for tremor.

Genetic predisposition to elevated levels of C-reactive protein is associated with a decreased risk for preeclampsia

OBJECTIVE

To examine the association between genetic predisposition to elevated C-reactive protein (CRP)and risk for preeclampsia using validated genetic loci for C-reactive protein.

METHODS

Preeclampsia cases (n = 177) and normotensive controls (n = 116) were selected from live birth certificates to nulliparous Iowa women during the period August 2002-May 2005. Disease status was verified by the medical chart review. Genetic predisposition to CRP was estimated by a genetic risk score on the basis of established loci for CRP levels. Logistic regression analyses were used to evaluate the relationships between the genotype score and preeclampsia. Replication analyses were performed in an independent, US population of preeclampsia cases (n = 516) and controls (n = 1,097) of European ancestry.

RESULTS

The genetic risk score (GRS) related to higher levels of CRP demonstrated a significantly decreased risk of preeclampsia (OR 0.89, 95% CI 0.82-0.96). When the GRS was analyzed by quartile, an inverse linear trend was observed (p = 0.0006). The results were similar after adjustments for the body mass index (BMI), smoking, and leisure-time physical activity. In the independent replication population, the association with the CRP GRS was also marginally significant (OR 0.97, 95% CI 0.92, 1.02). Meta-analysis of the two studies was statistically significant (OR 0.95, 95% CI 0.90, 0.99).

CONCLUSION

Our data suggest an inverse, counterintuitive association between the genetic predisposition to elevated levels of CRP and a decreased risk of preeclampsia. This suggests that the blood CRP level is a marker of preeclampsia, but it does not appear to be a factor on the causal pathway.

dbPEC: a comprehensive literature-based database for preeclampsia related genes and phenotypes

Preeclampsia is one of the most common causes of fetal and maternal morbidity and mortality in the world. We built a Database for Preeclampsia (dbPEC) consisting of the clinical features, concurrent conditions, published literature and genes associated with Preeclampsia. We included gene sets associated with severity, concurrent conditions, tissue sources and networks. The published scientific literature is the primary repository for all information documenting human disease. We used semantic data mining to retrieve and extract the articles pertaining to preeclampsia-associated genes and performed manual curation. We deposited the articles, genes, preeclampsia phenotypes and other supporting information into the dbPEC. It is publicly available and freely accessible. Previously, we developed a database for preterm birth (dbPTB) using a similar approach. Using the gene sets in dbPTB, we were able to successfully analyze a genome-wide study of preterm birth including 4000 women and children. We identified important genes and pathways associated with preterm birth that were not otherwise demonstrable using genome-wide approaches. dbPEC serves not only as a resources for genes and articles associated with preeclampsia, it is a robust source of gene sets to analyze a wide range of high-throughput data for gene set enrichment analysis. Database URL: http://ptbdb.cs.brown.edu/dbpec/.

Recombinant Human Antithrombin in Pregnant Patients with Hereditary Antithrombin Deficiency: Integrated Analysis of Clinical Data

OBJECTIVES

The purpose of this analysis was to evaluate the use of recombinant human antithrombin (rhAT) in preventing venous thromboembolism (VTE) in pregnant patients with hereditary AT deficiency (HATD).

STUDY DESIGN

Data from two clinical trials were pooled. Dosing of rhAT was based on body weight and baseline AT activity, started up to 24 hours before scheduled induction or cesarean delivery, or at the onset of labor.

RESULTS

A total of 21 pregnant HATD patients were enrolled. Mean rhAT therapy duration was 4.3 days and dose was 245.1 IU/kg/day. All patients achieved target mean AT activity (80-120% of normal) during rhAT therapy. There were no confirmed VTEs during rhAT treatment or within 7 ( ± 1) days after dosing. Two VTE events (one deep vein thrombosis and one pulmonary embolism) occurred 11 and 14 days after discontinuation of rhAT, in patients managed with prophylactic doses of heparin or low-molecular-weight heparin following delivery.

CONCLUSION

rhAT was safe and effective in pregnant HATD patients when administered during the peripartum period, the period of highest VTE risk and a time when anticoagulation therapy is normally withheld. Pregnant HATD patients may benefit from therapeutic, rather than prophylactic, doses of anticoagulation after delivery to protect against postpartum VTE.

Genetic Risk Score for Essential Hypertension and Risk of Preeclampsia

BACKGROUND

Preeclampsia is a hypertensive complication of pregnancy characterized by novel onset of hypertension after 20 weeks gestation, accompanied by proteinuria. Epidemiological evidence suggests that genetic susceptibility exists for preeclampsia; however, whether preeclampsia is the result of underlying genetic risk for essential hypertension has yet to be investigated. Based on the hypertensive state that is characteristic of preeclampsia, we aimed to determine if established genetic risk scores (GRSs) for hypertension and blood pressure are associated with preeclampsia.

METHODS

Subjects consisted of 162 preeclamptic cases and 108 normotensive pregnant controls, all of Iowa residence. Subjects' DNA was extracted from buccal swab samples and genotyped on the Affymetrix Genome-wide Human SNP Array 6.0 (Affymetrix, Santa Clara, CA). Missing genotypes were imputed using MaCH and Minimac software. GRSs were calculated for hypertension, systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) using established genetic risk loci for each outcome. Regression analyses were performed to determine the association between GRS and risk of preeclampsia. These analyses were replicated in an independent US population of 516 cases and 1,097 controls of European ancestry.

RESULTS

GRSs for hypertension, SBP, DBP, and MAP were not significantly associated with risk for preeclampsia (P > 0.189). The results of the replication analysis also yielded nonsignificant associations.

CONCLUSIONS

GRSs for hypertension and blood pressure are not associated with preeclampsia, suggesting that an underlying predisposition to essential hypertension is not on the causal pathway of preeclampsia.

Folic acid supplementation in early pregnancy and the risk of preeclampsia, small for gestational age offspring and preterm delivery

OBJECTIVE

To assess whether folic acid intake during the first trimester of pregnancy is related to pregnancy outcomes preeclampsia, low birth weight or preterm birth.

STUDY DESIGN

Prospective cohort study of 3647 women who were followed from the first trimester of pregnancy. Detailed information on quantity of folic acid intake before and during the first three months of pregnancy was recorded. Pregnancy outcome data were abstracted from obstetric records.

RESULTS

Lean mothers who used folic acid supplementation the month before pregnancy had a 40% reduced risk of developing preeclampsia. The adjusted odds ratio (OR) with 95% confidence intervals (95%CI) for preeclampsia in lean mothers (BMI<25) who used folic acid supplements the month before pregnancy was 0.6 (95% CI 0.4-1.0). Obese mothers who used folic acid supplementation in the first trimester had an increased, but not statistically significant risk for preterm birth (adjusted OR 1.9 with 95% CI 0.9-4.0). There were no significant associations between folic acid supplementation and low birth weight.

CONCLUSION

Our study supports a possible protective effect of folate intake in early pregnancy on preeclampsia in lean mothers. There was no support for any beneficial effect of folic acid use on preterm birth or low birth weight, and we found no evidence of any harmful effects of folate use for the outcomes included in our study.

The effect of labour induction on the risk of caesarean delivery: using propensity scores to control confounding by indication

OBJECTIVE

To use propensity score methods to control for confounding by indication in the association between labour induction and caesarean delivery.

DESIGN

Cross-sectional analysis of administrative hospital discharge data supplemented by medical record information.

SETTING

Fourteen US member hospitals of the National Perinatal Information Center.

SAMPLE

A cohort of 166 559 singleton liveborn deliveries in the period 2007-2012.

METHODS

We used propensity scores (PSs) to balance 83 covariates between induced and non-induced women, and compared estimates with traditional covariate adjustment. We estimated PSs for labour induction versus expectant management of pregnancy each week from 34 to 42 weeks of gestation. We estimated risk ratios (RRs) for the association between labour induction and primary caesarean delivery from models with no adjustment, traditional adjustment of five covariates, matched PS, and adjustment for continuous PS.

MAIN OUTCOME MEASURE

Caesarean delivery in current or subsequent week of gestation.

RESULTS

In crude models labour induction increased the risk of caesarean delivery in all weeks (RR 1.06-1.52), excepting 39 weeks of gestation (RR 0.89). After matching on PS, the analysis showed a significantly decreased risk of caesarean delivery with labour induction during weeks 35-39 (RR 0.77-0.92), and a significantly elevated risk at weeks 40 (RR 1.22) and 41 (RR 1.39). Traditional covariate and PS adjustment resulted in RRs between those from crude and PS-matched models.

CONCLUSIONS

There is evidence of considerable confounding by indication in the association of labour induction and caesarean delivery, particularly for preterm deliveries. Using PS methods, we found a reduced risk of caesarean delivery with labour induction before 40 weeks of gestation, and an elevated risk for weeks 40-42.

TWEETABLE ABSTRACT

With confounding adjustment, labour induction does not increase the risk of caesarean at 34-39 weeks of gestation.

Genetic Predisposition to Dyslipidemia and Risk of Preeclampsia

BACKGROUND

Large epidemiologic studies support the role of dyslipidemia in preeclampsia; however, the etiology of preeclampsia or whether dyslipidemia plays a causal role remains unclear. We examined the association between the genetic predisposition to dyslipidemia and risk of preeclampsia using validated genetic markers of dyslipidemia.

METHODS

Preeclampsia cases (n = 164) and normotensive controls (n = 110) were selected from live birth certificates to nulliparous Iowa women during the period August 2002 to May 2005. Disease status was verified by medical chart review. Genetic predisposition to dyslipidemia was estimated by 4 genetic risk scores (GRS) (total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), and triglycerides) on the basis of established loci for blood lipids. Logistic regression analyses were used to evaluate the relationships between each of the 4 genotype scores and preeclampsia. Replication analyses were performed in an independent, US population of preeclampsia cases (n = 516) and controls (n = 1,097) of European ancestry.

RESULTS

The GRS related to higher levels of TC, LDL-C, and triglycerides demonstrated no association with the risk of preeclampsia in either the Iowa or replication population. The GRS related to lower HDL-C was marginally associated with an increased risk for preeclampsia (odds ratio (OR) = 1.03, 95% confidence interval (CI) = 0.99-1.07; P = 0.10). In the independent replication population, the association with the HDL-C GRS was also marginally significant (OR = 1.03, 95% CI: 1.00-1.06; P = 0.04).

CONCLUSIONS

Our data suggest a potential effect between the genetic predisposition to dyslipidemic levels of HDL-C and an increased risk of preeclampsia, and, as such, suggest that dyslipidemia may be a component along the causal pathway to preeclampsia.

Cigarette smoking and emergency care utilization among asthmatic adults in the 2011 Asthma Call-back Survey

OBJECTIVE

Estimate the association between smoking and emergency care in the past 12 months among asthmatic adults in a nationally representative sample.

METHODS

Using the 2011 Asthma Call-Back Survey, the association between smoking status and emergency department (ED) and urgent visits among asthmatic adults (n = 12 339) was assessed through multivariable logistic regression by a cross-sectional study design. Analyses used survey weights for US population-based estimates. Attributable and population attributable risk were calculated to describe the potential benefits of smoking cessation.

RESULTS

Adjusting for potential confounders, during the past 12 months former smokers had 1.30 (95% CI: 0.97, 1.74) times the odds and current smokers had 1.46 (95% CI: 1.05, 2.03) times the odds of visiting the ED compared to never smokers. Former smokers had 1.28 (95% CI: 0.99, 1.65) times the odds and current smokers had 1.29 (95% CI: 0.96, 1.73) times the odds of urgent visits compared to never smokers. Among adult asthmatics, an estimated 9% of ED visits and 6% of urgent visits can be attributed to current smoking while 7% of ED visits and 7% of urgent visits can be attributed to former smoking.

CONCLUSIONS

Current and former smokers are more likely to need emergency care than never smokers. About 10% of emergency care visits among asthmatics can be attributed to smoking assuming smoking is causally related to emergency care. Long-term effective management of asthma, particularly the prevention and cessation of smoking, could reduce emergency care use and health care costs.

A Pilot Study: examining the effects and tolerability of structured dance intervention for individuals with multiple sclerosis

PURPOSE

The aims of this pilot were to examine dance as a feasible intervention for persons with multiple sclerosis (MS), specifically to examine issues of tolerability and its longitudinal effects on participants. Dance is an enjoyable physical activity that has been investigated in other neurodegenerative populations but has yet to be studied in MS.

METHOD

A 4-week, two 60-min classes per week, pilot salsa dance intervention was administered to eight individuals with MS. The outcomes measured were effects on gait, balance, self-efficacy, motivation, physical activity and MS symptoms. They were administered at baseline, immediately post-intervention and at 3- and 6-month follow-ups.

RESULTS

Statistically significant pre-post intervention gains were found for the Timed Up and Go Test (TUG), Dynamic Gait Index (DGI), Activities-specific Balance Confidence Scale and Godin Leisure Time Questionnaire. Significant improvements were also found for the TUG, DGI and MS Walking Scale between baseline and 3-month follow-up assessments. Participants did not report any problems with fatigue or intolerability with the 60-min suggestions, further supporting the feasibility for the concept of a dance intervention.

CONCLUSIONS

This study suggests that dance for persons with MS may have promise for improving physical activity, gait and balance.

IMPLICATIONS FOR REHABILITATION

Although structured dance has reported benefits in elderly populations and in individuals with cardiovascular and neurological impairments, there is virtually nothing known regarding dance in the MS population. This pilot salsa dance study shows that structured dance demonstrates promise of being well-tolerated, safe and effective at promoting physical activity in people with MS without increased fatigue. A 12-week study has been initiated to test the robustness of initial observations and further examine factors influencing participants' physical activity adherence and behavioral change.

Gestational weight gain among American Samoan women and its impact on delivery and infant outcomes

BACKGROUND

As obesity has increased worldwide, so have levels of obesity during pregnancy and excess gestational weight gain (GWG). The aim of this paper was to describe GWG among American Samoan women and examine the association between GWG and four adverse pregnancy and infant outcomes: cesarean delivery, small- and large-for-gestational age (SGA/LGA), and infant overweight/obesity.

METHODS

Data were extracted from prenatal care records of 632 Samoan women. Mixed-effects growth models were used to produce individual weight-for-gestational week curves from which second and third trimester weight gain was estimated. Binary logistic regression was used to examine associations between GWG and the outcomes of interest.

RESULTS

Most women were overweight/obese in early pregnancy (86%) and 78% exceeded the Institute of Medicine GWG guidelines. Greater GWG in the second trimester and early pregnancy weight were independently associated with increased odds of a c-section (OR 1.40 [95% CI: 1.08, 1.83]) and OR 1.51 [95% CI: 1.17, 1.95], respectively). Risk of delivering a LGA infant increased with greater third trimester weight gain and higher early pregnancy weight, while second trimester weight gain was negatively associated with SGA. Risk of infant overweight/obesity at 12 months increased with early pregnancy weight (OR: 1.23 [95% CI: 1.01, 1.51]) and infant birthweight.

CONCLUSIONS

The high levels of pregnancy obesity and excessive GWG in American Samoa suggest that it is important for physicians to encourage women into prenatal care early and begin education about appropriate GWG and the potential risks of excess weight gain for both the mother and baby.

The relationship between parental stress and postpartum depression among adolescent mothers enrolled in a randomized controlled prevention trial

Given the high co-occurrence of depression and parental stress among adolescent mothers, we evaluated the relationship between parental stress and postpartum depression among primiparous adolescent mothers. We conducted an observational analysis among a cohort of 106 adolescent mothers at 289 postpartum visits who were enrolled in a randomized controlled trial to prevent postpartum depression. Parental stress was measured using the Parenting Stress Index, short form. The Structured Clinical Interview for DSM-IV Childhood Diagnoses was administered to assess for postpartum depression; subthreshold depression was assessed using the Children's Depression Rating Scale, revised version. Generalized estimating equations were utilized to assess the relationship of parental stress on postpartum depression during the first 6 months postpartum. We present adjusted odds ratios (AOR) controlling for study arm, age, born in the United States, prior history of depression, and number of study visits. The median age was 16 years, 53% were Latina, and 16% reported a past history of depression. Nineteen adolescents (19%) were diagnosed with postpartum depression and 25% experienced high levels of parental stress through 6 months postpartum. Adolescent mothers who reported higher levels of parental stress were at significantly increased risk for postpartum depression [AOR 1.06 (95% CI 1.04-1.09); p < 0.0001]. High levels of parental stress predicted subsequent postpartum depression when assessing parental stress at visits prior to a depression diagnosis to determine whether we could establish a temporal association [AOR 1.06 (95% CI 1.02-1.09); p < 0.01]. Parental stress was also a risk factor for subthreshold depression [AOR 1.04 (95% CI 1.01-1.07); p < 0.01]. Parental stress was a significant risk factor for developing both postpartum depression as well as subthreshold depression among adolescent mothers. Interventions that target a reduction in parental stress may lead to less depression severity among primiparous adolescent mothers.

Mediterranean and Dietary Approaches to Stop Hypertension dietary patterns and risk of sudden cardiac death in postmenopausal women

BACKGROUND

The Mediterranean and Dietary Approaches to Stop Hypertension (DASH) diets are characterized by higher intake of fruit, vegetables, whole grains, and unsaturated fatty acids. All of these foods and nutrients may affect cholesterol, inflammation, the development of atherosclerosis, and, therefore, risk of cardiac death.

OBJECTIVE

Our objective was to examine the association between the Mediterranean and DASH dietary patterns and risk of sudden cardiac death (SCD) in women.

DESIGN

We used a prospective cohort of 93,122 postmenopausal women enrolled in the Women's Health Initiative study between 1993 and 1998 and followed for an average of 10.5 y. Women completed a food-frequency questionnaire (FFQ) twice during follow-up. We scored their diets according to how closely the reported diet resembled each dietary pattern. SCD was defined as death that occurred within 1 h of symptom onset.

RESULTS

A higher Mediterranean diet score was associated with lower risk of SCD (HR: 0.64; 95% CI: 0.43, 0.94) when women in the highest quintile were compared with women in the lowest quintile after adjustment for age, total energy, race, income, smoking, and physical activity. After adjustment for potential mediators, the association was similar (HR: 0.67; 95% CI: 0.46, 0.99). A higher DASH diet score was not associated with risk of SCD. However, sodium intake, which is a crucial component of the DASH dietary pattern, was not well characterized by the FFQ.

CONCLUSION

The Mediterranean dietary pattern may be associated with lower risk of SCD in women. This trial was registered at clinicaltrials.gov as NCT00000611.

Accuracy of brief screening tools for identifying postpartum depression among adolescent mothers

OBJECTIVE

To evaluate the accuracy of the Edinburgh Postnatal Depression Scale (EPDS) and 3 subscales for identifying postpartum depression among primiparous adolescent mothers.

METHODS

Mothers enrolled in a randomized controlled trial to prevent postpartum depression completed a psychiatric diagnostic interview and the 10-item EPDS at 6 weeks, 3 months, and 6 months postpartum. Three subscales of the EPDS were assessed as brief screening tools: 3-item anxiety subscale (EPDS-3), 7-item depressive symptoms subscale (EPDS-7), and 2-item subscale (EPDS-2) that resemble the Patient Health Questionnaire-2. Receiver operating characteristic curves and the areas under the curves for each tool were compared to assess accuracy. The sensitivities and specificities of each screening tool were calculated in comparison with diagnostic criteria for a major depressive disorder. Repeated-measures longitudinal analytical techniques were used.

RESULTS

A total of 106 women contributed 289 postpartum visits; 18% of the women met criteria for incident postpartum depression by psychiatric diagnostic interview. When used as continuous measures, the full EPDS, EPDS-7, and EPDS-2 performed equally well (area under the curve >0.9). Optimal cutoff scores for a positive depression screen for the EPDS and EPDS-7 were lower (≥ 9 and ≥ 7, respectively) than currently recommended cutoff scores (≥ 10). At optimal cutoff scores, the EPDS and EPDS-7 both had sensitivities of 90% and specificities of >85%.

CONCLUSIONS

The EPDS, EPDS-7, and EPDS-2 are highly accurate at identifying postpartum depression among adolescent mothers. In primary care pediatric settings, the EPDS and its shorter subscales have potential for use as effective depression screening tools.

The association between epilepsy and autism symptoms and maladaptive behaviors in children with autism spectrum disorder

Epilepsy is common in children with autism spectrum disorder (ASD) but little is known about how seizures impact the autism phenotype. The association between epilepsy and autism symptoms and associated maladaptive behaviors was examined in 2,645 children with ASD, of whom 139 had epilepsy, from the Simons Simplex Collection. Children with ASD and epilepsy had significantly more autism symptoms and maladaptive behaviors than children without epilepsy. However, after adjusting for IQ, only hyperactivity symptoms remained significantly increased (13% higher) in the epilepsy group. Among children with ASD without co-occurring intellectual disability, children with epilepsy had significantly more irritability (20% higher) and hyperactivity (24% higher) symptoms. This is the largest study to date comparing the autism phenotype in children with ASD with and without epilepsy. Children with ASD and epilepsy showed greater impairment than children without epilepsy, which was mostly explained by the lower IQ of the epilepsy group. These findings have important clinical implications for patients with ASD.

Cumulative exposure to paternal seminal fluid prior to conception and subsequent risk of preeclampsia

A growing body of literature suggests that prior and prolonged exposure to paternal antigens in seminal fluid induces maternal tolerance to the allogeneic fetus, protecting it from rejection and facilitating successful implantation and placentation. In this case-control study of nulliparous women, we test the hypothesis that increased exposure to paternal seminal fluid via the vaginal or oral route will confer a reduced risk of preeclampsia. Preeclampsia cases (n=258) and normotensive controls (n=182) were selected from live births to Iowa women over the period August 2002 to April 2005. Disease status was verified by medical chart review. Seminal fluid exposure indexes incorporated information on type and frequency of sexual practices, contraceptive use, and ingestion practices prior to conception with the baby's father. Preeclampsia risk decreased significantly with increasing vaginal exposure to paternal semen (test for trend p<0.05). Women in the highest 10th percentile of vaginal exposure had a 70% reduced odds of preeclampsia relative to women in the lowest 25th percentile of exposure (aOR=0.3; 95% CI: 0.1-0.9). Oral seminal fluid exposure was not associated with a reduced risk of preeclampsia. These findings are congruent with the immune maladaptation hypothesis of preeclampsia causation and indicate that paternal antigen exposure via the vaginal mucosa may facilitate immune tolerance to paternal HLA. Thus, advising nulliparous women to decrease their use of barrier contraceptive methods and to increase vaginal sexual intercourse prior to conceiving may reduce their risk of preeclampsia.

Maternal-fetal HLA sharing and preeclampsia: variation in effects by seminal fluid exposure in a case-control study of nulliparous women in Iowa

Whereas histocompatibility is critical for transplantation, HLA histoincompatibility is associated with successful pregnancy. Literature on HLA sharing and preeclampsia has been inconsistent; most studies focused on maternal-paternal rather than maternal-fetal sharing. This study examines whether maternal-fetal histocompatibility is associated with preeclampsia, and whether effects vary by semen exposure history. This case-control study of nulliparous women was designed to examine associations among HLA sharing, semen exposure, and preeclampsia. 258 preeclampsia cases and 182 normotensive controls met the eligibility criteria. HLA typing for mother and baby was performed for HLA-A, -B, -C, -DRB1, and -DQB1. We further restricted our study sample to 224 mother-baby pairs who had complete HLA typing for all five genes. Seminal fluid exposure indexes incorporated information on type of practice, frequency, contraceptive use (for vaginal exposure) and ingestion practices (for oral exposure). Multivariate models were adjusted for BMI and education. HLA-A matching, Class I matching, and combined Class I and II matching were associated with increased odds of preeclampsia. Among women with low semen exposure, effects of Class I matching were amplified (HLA-A matching, OR=6.27, 95%CI=1.04, 37.97; Class I matching, OR=4.49 per one-match increase, 95%CI=1.89, 14.50). With moderate to high semen exposure, Class II matching effects predominated (HLA-DQB1, OR=3.22, 95%CI=1.04, 9.99; Class II, OR=1.76 per one-match increase, 95%CI=1.05, 2.98; and total matches, OR=1.45 per one-match increase, 95%CI=1.02, 2.06). We found consistent evidence that maternal-fetal HLA sharing was associated with preeclampsia in a pattern influenced by prior vaginal exposure to paternal seminal fluid.

Clinical characteristics of children with autism spectrum disorder and co-occurring epilepsy

Objectives

To estimate the prevalence of epilepsy in children with Autism Spectrum Disorder (ASD) and to determine the demographic and clinical characteristics of children with ASD and epilepsy in a large patient population.

Methods

Cross-sectional study using four samples of children with ASD for a total of 5,815 participants with ASD. The prevalence of epilepsy was estimated from a population-based sample. Children with and without epilepsy were compared on demographic and clinical characteristics. Multivariate logistic regression was used to examine the association between demographic and clinical characteristics and epilepsy.

Results

The average prevalence of epilepsy in children with ASD 2–17 years was 12.5%; among children aged 13 years and older, 26% had epilepsy. Epilepsy was associated with older age, lower cognitive ability, poorer adaptive and language functioning, a history of developmental regression and more severe ASD symptoms. The association between epilepsy and the majority of these characteristics appears to be driven by the lower IQ of participants with epilepsy. In a multivariate regression model, only age and cognitive ability were independently associated with epilepsy. Children age 10 or older had 2.35 times the odds of being diagnosed with epilepsy (p<.001) and for a one standard deviation increase in IQ, the odds of having epilepsy decreased by 47% (p<.001).

Conclusion

This is among the largest studies to date of patients with ASD and co-occurring epilepsy. Based on a representative sample of children with ASD, the average prevalence of epilepsy is approximately 12% and reaches 26% by adolescence. Independent associations were found between epilepsy and older age and lower cognitive ability. Other risk factors, such as poor language and developmental regression, are not associated with epilepsy after controlling for IQ. These findings can help guide prognosis and alert clinicians to patients with ASD who are at increased risk for epilepsy.

Long-term alcohol and caffeine intake and risk of sudden cardiac death in women

BACKGROUND

Alcohol and caffeine intakes may play a role in the development of sudden cardiac death (SCD) because of their effects on cholesterol, blood pressure, heart rate variability, and inflammation.

OBJECTIVE

Our objective was to examine the association between long-term alcohol and caffeine intakes and risk of SCD in women.

DESIGN

We examined 93,676 postmenopausal women who participated in the Women's Health Initiative Observational Study. Women were enrolled between 1993 and 1998 and were followed until August 2009. Women completed a food-frequency questionnaire at baseline and again at year 3. We modeled exposure to alcohol 3 ways: by using baseline intake only, a cumulative average of baseline and year 3 intake, and the most recent reported intake (a simple time-varying analysis).

RESULTS

Intake of 5-15 g alcohol/d (about one drink) was associated with a nonsignificantly reduced risk of SCD compared with 0.1-5 g/d of baseline intake (HR: 0.64; 95% CI: 0.40, 1.02), of cumulative average intake (HR: 0.69; 95% CI: 0.43, 1.11), and of most recent intake (HR: 0.58; 95% CI: 0.35, 0.96), with adjustment for age, race, income, smoking, body mass index, physical activity, hormone use, and total energy. No association was found between SCD and total caffeine intake (mg/d) or cups of caffeinated coffee, decaffeinated coffee, and caffeinated tea.

CONCLUSIONS

Our results suggest that about one drink per day (or 5.1-15 g/d) may be associated with a reduced risk of SCD in this population; however, this association was only statistically significant for a model using the most recent alcohol intake. Total caffeine, regular coffee, decaffeinated coffee, and regular tea intake were not associated with the risk of SCD. This trial was registered at clinicaltrials.gov as NCT00000611.

Exploring the role of antithrombin replacement for the treatment of preeclampsia: a prospective randomized evaluation of the safety and efficacy of recombinant antithrombin in very preterm preeclampsia (PRESERVE-1)

PROBLEM

Antithrombin (AT) replacement has been described in patients with hereditary AT deficiency undergoing delivery; however, the kinetics of AT replacement in preeclampsia is not adequately understood. Therefore, the Prospective Randomized Evaluation of the Safety and Efficacy of Recombinant Antithrombin in Very Preterm Preeclampsia (PRESERVE-1) study has been proposed.

METHODS

Sixty women aged≥18 years at 24 0/7-28 0/7 weeks' gestation and with hypertension and proteinuria will be enrolled and randomly assigned to receive recombinant human AT or placebo until fetal and/or maternal indications cause cessation of expectant management or until 34 0/7 weeks' gestation. The primary endpoint is the increase in gestational age from randomization to delivery. Safety assessments and laboratory assays will also be performed.

RESULTS

PRESERVE-1 study enrollment will begin during the second half of 2013.

CONCLUSION

The PRESERVE-1 study will provide further insight into the pharmacokinetic activity and safety of AT therapy in preeclampsia.

Implementing provider-based sampling for the National Children's Study: opportunities and challenges

BACKGROUND

The National Children's Study (NCS) was established as a national probability sample of births to prospectively study children's health starting from in utero to age 21. The primary sampling unit was 105 study locations (typically a county). The secondary sampling unit was the geographic unit (segment), but this was subsequently perceived to be an inefficient strategy.

METHODS AND RESULTS

This paper proposes that second-stage sampling using prenatal care providers is an efficient and cost-effective method for deriving a national probability sample of births in the US. It offers a rationale for provider-based sampling and discusses a number of strategies for assembling a sampling frame of providers. Also presented are special challenges to provider-based sampling pregnancies, including optimising key sample parameters, retaining geographic diversity, determining the types of providers to include in the sample frame, recruiting women who do not receive prenatal care, and using community engagement to enrol women. There will also be substantial operational challenges to sampling provider groups.

CONCLUSION

We argue that probability sampling is mandatory to capture the full variation in exposure and outcomes expected in a national cohort study, to provide valid and generalisable risk estimates, and to accurately estimate policy (such as screening) benefits from associations reported in the NCS.

Correction of systematic bias in ultrasound dating in studies of small-for-gestational-age birth: an example from the Iowa Health in Pregnancy Study

The authors examined whether early ultrasound dating (≤20 weeks) of gestational age (GA) in small-for-gestational-age (SGA) fetuses may underestimate gestational duration and therefore the incidence of SGA birth. Within a population-based case-control study (May 2002-June 2005) of Iowa SGA births and preterm deliveries identified from birth records (n = 2,709), the authors illustrate a novel methodological approach with which to assess and correct for systematic underestimation of GA by early ultrasound in women with suspected SGA fetuses. After restricting the analysis to subjects with first-trimester prenatal care, a nonmissing date of the last menstrual period (LMP), and early ultrasound (n = 1,135), SGA subjects' ultrasound GA was 5.5 days less than their LMP GA, on average. Multivariable linear regression was conducted to determine the extent to which ultrasound GA predicted LMP dating and to correct for systematic misclassification that results after applying standard guidelines to adjudicate differences in these measures. In the unadjusted model, SGA subjects required a correction of +1.5 weeks to the ultrasound estimate. With adjustment for maternal age, smoking, and first-trimester vaginal bleeding, standard guidelines for adjudicating differences in ultrasound and LMP dating underestimated SGA birth by 12.9% and overestimated preterm delivery by 8.7%. This methodological approach can be applied by researchers using different study populations in similar research contexts.

Genome-wide association study identifies a maternal copy-number deletion in PSG11 enriched among preeclampsia patients

Background

Specific genetic contributions for preeclampsia (PE) are currently unknown. This genome-wide association study (GWAS) aims to identify maternal single nucleotide polymorphisms (SNPs) and copy-number variants (CNVs) involved in the etiology of PE.

Methods

A genome-wide scan was performed on 177 PE cases (diagnosed according to National Heart, Lung and Blood Institute guidelines) and 116 normotensive controls. White female study subjects from Iowa were genotyped on Affymetrix SNP 6.0 microarrays. CNV calls made using a combination of four detection algorithms (Birdseye, Canary, PennCNV, and QuantiSNP) were merged using CNVision and screened with stringent prioritization criteria. Due to limited DNA quantities and the deleterious nature of copy-number deletions, it was decided a priori that only deletions would be selected for assay on the entire case-control dataset using quantitative real-time PCR.

Results

The top four SNP candidates had an allelic or genotypic p-value between 10^-5 and 10^-6, however, none surpassed the Bonferroni-corrected significance threshold. Three recurrent rare deletions meeting prioritization criteria detected in multiple cases were selected for targeted genotyping. A locus of particular interest was found showing an enrichment of case deletions in 19q13.31 (5/169 cases and 1/114 controls), which encompasses the PSG11 gene contiguous to a highly plastic genomic region. All algorithm calls for these regions were assay confirmed.

Conclusions

CNVs may confer risk for PE and represent interesting regions that warrant further investigation. Top SNP candidates identified from the GWAS, although not genome-wide significant, may be useful to inform future studies in PE genetics.

Association of variants in innate immune genes with asthma and eczema

BACKGROUND

The innate immune pathway is important in the pathogenesis of asthma and eczema. However, only a few variants in these genes have been associated with either disease. We investigate the association between polymorphisms of genes in the innate immune pathway with childhood asthma and eczema. In addition, we compare individual associations with those discovered using a multivariate approach.

METHODS

Using a novel method, case control based association testing (C2BAT), 569 single nucleotide polymorphisms (SNPs) in 44 innate immune genes were tested for association with asthma and eczema in children from the Boston Home Allergens and Asthma Study and the Connecticut Childhood Asthma Study. The screening algorithm was used to identify the top SNPs associated with asthma and eczema. We next investigated the interaction of innate immune variants with asthma and eczema risk using Bayesian networks.

RESULTS

After correction for multiple comparisons, 7 SNPs in 6 genes (CARD25, TGFB1, LY96, ACAA1, DEFB1, and IFNG) were associated with asthma (adjusted p-value<0.02), while 5 SNPs in 3 different genes (CD80, STAT4, and IRAKI) were significantly associated with eczema (adjusted p-value < 0.02). None of these SNPs were associated with both asthma and eczema. Bayesian network analysis identified 4 SNPs that were predictive of asthma and 10 SNPs that predicted eczema. Of the genes identified using Bayesian networks, only CD80 was associated with eczema in the single-SNP study. Using novel methodology that allows for screening and replication in the same population, we have identified associations of innate immune genes with asthma and eczema. Bayesian network analysis suggests that additional SNPs influence disease susceptibility via SNP interactions.

CONCLUSION

Our findings suggest that innate immune genes contribute to the pathogenesis of asthma and eczema, and that these diseases likely have different genetic determinants.

Sexual risk behaviors among HIV-infected South African men and women with their partners in a primary care program: implications for couples-based prevention

We studied 1163 sexually-active HIV-infected South African men and women in an urban primary care program to understand patterns of sexual behaviors and whether these behaviors differed by partner HIV status. Overall, 40% reported a HIV-positive partner and 60% a HIV-negative or status unknown partner; and 17.5% reported >2 sex acts in the last 2 weeks, 16.4% unprotected sex in the last 6 months, and 3.7% >1 sex partner in the last 6 months. Antiretroviral therapy (ART) was consistently associated with decreased sexual risk behaviors, as well as with reporting a HIV-negative or status unknown partner. The odds of sexual risk behaviors differed by sex; and were generally higher among participants reporting a HIV-positive partner, but continued among those with a HIV-negative or status unknown partner. These data support ART as a means of HIV prevention. Engaging in sexual risk behaviors primarily with HIV-positive partners was not widely practiced in this setting, emphasizing the need for couples-based prevention.

Spatial and temporal modeling of daily pollen concentrations

Accurate assessments of pollen counts are valuable to allergy sufferers, the medical industry, and health researchers; however, monitoring stations do not exist in most areas. In addition, the degree of spatial reliability provided by the limited number of monitoring stations is poorly understood. We developed and compared spatial models to estimate pollen concentrations in locations without monitoring stations. Daily Acer, Quercus, and overall tree, grass, and weed pollen counts, in grains/m(3), were obtained from 14 aeroallergen monitoring stations located in the northeastern and mid-Atlantic region of the United States from 2003 to 2006. Pollen counts were spatially interpolated using ordinary kriging. Mixed effects and generalized estimating equations incorporating daily and seasonal weather characteristics, pollen season characteristics and land-cover information were also developed to estimate daily pollen concentrations. We then compared observed values from a monitoring station to model estimates for that location. Observed counts and kriging estimates for tree pollen differed (p = 0.04), but not when peak periods were removed (p = 0.29). No differences between observed and kriging estimates of Acer (p = 0.46), Quercus (p = 0.24), grass (p = 0.31) or weed pollen (p = 0.29) were found. Estimates from longitudinal models also demonstrated good agreement with observed counts, except for the extremes of pollen distributions. Our results demonstrate that spatial interpolation techniques as well as regression methods incorporating both weather and land-cover characteristics can provide reliable estimates of daily pollen concentrations in areas where monitors do not exist for all but periods of extremely high pollen.

Effects of endotoxin exposure on childhood asthma risk are modified by a genetic polymorphism in ACAA1

Background

Polymorphisms in the endotoxin-mediated TLR4 pathway genes have been associated with asthma and atopy. We aimed to examine how genetic polymorphisms in innate immunity pathways interact with endotoxin to influence asthma risk in children.

Methods

In a previous analysis of 372 children from the Boston Home Allergens and the Connecticut Childhood Asthma studies, 7 SNPs in 6 genes (CARD15, TGFB1, LY96, ACAA1, DEFB1 and IFNG) involved in innate immune pathways were associated with asthma, and 5 SNPs in 3 genes (CD80, STAT4, IRAK2) were associated with eczema. We tested these SNPs for interaction with early life endotoxin exposure (n = 291), in models for asthma and eczema by age 6.

Results

We found a significant interaction between endotoxin and a SNP (rs156265) in ACAA1 (p = 0.0013 for interaction). Increased endotoxin exposure (by quartile) showed protective effects for asthma in individuals with at least one copy of the minor allele (OR = 0.39 per quartile increase in endotoxin, 95% CI 0.15 to 1.01). Endotoxin exposure did not reduce the risk of asthma in children homozygous for the major allele.

Conclusion

Our findings suggest that protective effects of endotoxin exposure on asthma may vary depending upon the presence or absence of a polymorphism in ACAA1.

Effect of robot-assisted versus conventional body-weight-supported treadmill training on quality of life for people with multiple sclerosis

This study describes the effect of body-weight-supported treadmill training (BWSTT) on quality of life (QoL) for multiple sclerosis (MS) patients. Thirteen individuals with MS and gait impairment randomly received two blocks of six biweekly training sessions: (1) robot-assisted BWSTT then BWSTT alone (R-T) or (2) BWSTT alone then robot-assisted BWSTT (T-R). No statistically significant differences were found between robot-assisted BWSTT and unassisted BWSTT for improving QoL outcome measures. The change in Physical Component Summary scores from baseline to the end of the 12 training sessions improved significantly more in the R-T than the T-R group. Within-participant longitudinal changes in QoL for all participants from both groups combined showed significant improvements in 5 of the 13 QoL measures. The results of this pilot study suggest that both types of BWSTT may improve QoL for people with gait dysfunction secondary to MS.

Growth of infants born to HIV-infected women in South Africa according to maternal and infant characteristics

OBJECTIVE

To evaluate growth parameters assessed by weight and length in HIV-infected and HIV-uninfected infants born to HIV-infected mothers in South Africa from birth to 6 months of age.

METHODS

We calculated z-scores for weight-for-age (WAZ), length-for-age (LAZ) and weight-for-length (WLZ) among a cohort of 840 mother-infant dyads. Multivariable Cox proportional hazards models with time-varying covariates were used to estimate the risk of falling <-2 z-scores for WAZ, LAZ, and WLZ as a function of infant and maternal characteristics.

RESULTS

By 6 months after birth, a fifth of infants had WAZ <-2, 19% had an LAZ <-2, and 29% had a WLZ <-2. WLZ and WAZ were significantly lower in HIV-infected infants than in uninfected infants by 3 months of age and LAZ by 6 months of age (P<0.001). The risk of WAZ falling <-2 was associated with decreasing maternal CD4 cell count (adj. HR for CD4 cell count <200 cells/μl: 1.64; 95% CI: 1.10-2.43), premature birth (adj. HR: 2.82; 95% CI: 2.06-3.86) and formula feeding (adj. HR: 3.35; 95% CI: 1.64-6.85). The risk of LAZ falling <-2 was associated with increasingly lower maternal age (adj. HR for<20 years: 0.54; 95% CI: 0.31-0.96), lower maternal CD4 cell count (adj. HR for CD4 cell count <200 cells/μl: 1.72; 95% CI: 1.14-2.59), premature birth (adj. HR: 2.37; 95% CI: 1.70-3.30) and formula feeding (adj. HR: 4.22; 95% CI: 1.85-9.62). The risk of WLZ falling <-2 was significantly associated with infant HIV infection (adj. HR: 1.64; 95% CI: 1.16-2.32) and formula feeding (adj. HR: 1.78; 95% CI: 1.11-2.83). The risk of WAZ and LAZ falling <-2 was more than two times greater for HIV-infected infants than for uninfected infants with gastrointestinal infections.

CONCLUSIONS

HIV-infected infants were more likely to be stunted and wasted than uninfected infants, which often occurred within 3 months after birth. Infants who were born to mothers with advanced HIV disease, formula-fed and co-infected with HIV and gastrointestinal infections were at greater risk for growth disturbances. Further interventions are needed to promptly initiate both HIV-infected mothers and infants on appropriate antiretroviral therapy and nutritional supplementation.

Sexual risk behaviors among HIV-infected South Indian couples in the HAART era: implications for reproductive health and HIV care delivery

The current study examines sexual behaviors among HIV-infected Indians in primary care, where access to highly active antiretroviral therapy (HAART) has recently increased. Between January and April 2008, we assessed the sexual behaviors of 247 HIV-infected South Indians in care. Multivariable logistic regression models were used to determine predictors of being in a HIV-seroconcordant primary relationship, being sexually active, and reporting unprotected sex. Over three-fourths (80%) of participants were HAART-experienced. Among the 58% of participants who were currently in a seroconcordant relationship, one-third were serodiscordant when enrolling into care. Approximately two-thirds (63.2%) of participants were sexually active; 9.0% reported unprotected sex. In the multivariable analyses, participants who were in a seroconcordant primary relationship were more likely to have children, use alcohol, report unprotected sex, and have been enrolled in care for >12 months. Sexually active participants were more likely to be on HAART, have a prior tuberculosis diagnosis, test Herpes simplex type 2 antibody seropositive, and have low general health perceptions. Participants who reported unprotected sex were more likely to be in a seroconcordant relationship, be childless, want to have a child, and use alcohol. We did not document an association between HAART and unprotected sex. Among HIV-infected Indians in primary care, predictors of unprotected sex included alcohol use and desire for children. Prevention interventions for Indian couples should integrate reproductive health and alcohol use counseling at entry into care.

Morbidity and mortality among infants born to HIV-infected women in South Africa: implications for child health in resource-limited settings

BACKGROUND

We examined correlates of infant morbidity and mortality within the first 3 months of life among HIV-exposed infants receiving post-exposure antiretroviral prophylaxis in South Africa.

METHODS

We conducted a prospective cohort study of 848 mother-child dyads. Multivariable Cox proportional hazards models were used.

RESULTS

The main causes of infant morbidity were gastrointestinal and respiratory infections. Morbidity was higher with infant HIV infection (HR: 2.61; 95% CI: 1.40-4.85; p = 0.002) and maternal plasma viral load (PVL) >100,000 copies ml⁻¹ (HR: 1.87; 95% CI: 1.01-3.48; p = 0.048), and lower with maternal age < 20 years (HR: 0.25; 95% CI: 0.07-0.88; p = 0.031). Mortality was higher with infant HIV infection (HR: 4.10; 95% CI: 1.18-14.31; p = 0.027) and maternal PVL >100,000 copies ml⁻¹ (HR: 6.93; 95% CI: 1.64-29.26; p = 0.008). Infant feeding status did not influence the risk of morbidity nor mortality.

CONCLUSIONS

Future interventions that minimize pediatric HIV infection and reduce maternal viremia, which are the main predictors of child health soon after birth, will impact positively on infant health outcomes.

Prenatal factors for childhood blood pressure mediated by intrauterine and/or childhood growth?

OBJECTIVE

Some prenatal factors may program an offspring's blood pressure, but existing evidence is inconclusive and mechanisms remain unclear. We examined the mediating roles of intrauterine and childhood growth in the associations between childhood systolic blood pressure (SBP) and 5 potentially modifiable prenatal factors: maternal smoking during pregnancy; prepregnancy BMI; pregnancy weight gain; chronic hypertension; and preeclampsia-eclampsia.

METHODS

The sample contained 30 461 mother-child pairs in the Collaborative Perinatal Project. Prenatal data were extracted from obstetric forms, and children's SBP was measured at 7 years of age. Potential mediation by intrauterine growth restriction (IUGR) and childhood growth was examined by the causal step method.

RESULTS

Heavy maternal smoking during pregnancy was significantly associated with higher offspring SBP (adjusted mean difference versus nonsmoking: 0.73 mm Hg [95% confidence interval (CI): 0.32-1.14]), which attenuated to null (0.13 [95% CI: -0.27-0.54]) after adjustment for changes in BMI from birth to 7 years of age. Prepregnancy overweight-obesity was significantly associated with higher offspring SBP (versus normal weight: 0.89 mm Hg [95% CI: 0.52-1.26]), which also attenuated to null (-0.04 mm Hg [95% CI: -0.40-0.31]) after adjustment for childhood BMI trajectory. Adjustment for BMI trajectory augmented the association between maternal pregnancy weight gain and offspring SBP. Adjustment for childhood weight trajectory similarly changed these associations. However, all these associations were independent of IUGR.

CONCLUSIONS

Childhood BMI and weight trajectory, but not IUGR, may largely mediate the associations of maternal smoking during pregnancy and prepregnancy BMI with an offspring's SBP.

Predictors of nonadherence to highly active antiretroviral therapy among HIV-infected South Indians in clinical care: implications for developing adherence interventions in resource-limited settings

In light of the increasing availability of generic highly active antiretroviral therapy (HAART) in India, further data are needed to examine variables associated with HAART nonadherence among HIV-infected Indians in clinical care. We conducted a cross-sectional analysis of 198 HIV-infected South Indian men and women between January and April 2008 receiving first-line non-nucleoside reverse transcriptase inhibitor (NNRTI)-based HAART. Nonadherence was defined as taking less than 95% of HAART doses in the last 1 month, and was examined using multivariable logistic regression models. Half of the participants reported less than 95% adherence to HAART, and 50% had been on HAART for more than 24 months. The median CD4 cell count was 435 cells per microliter. An increased odds of nonadherence was found for participants with current CD4 cell counts greater than 500 cells per microliter (adjusted odds ratio [AOR]: 2.22 [95% confidence interval {CI}: 1.04-4.75]; p = 0.038), who were on HAART for more than 24 months (AOR: 3.07 [95% CI: 1.35-7.01]; p = 0.007), who reported alcohol use (AOR: 5.68 [95%CI: 2.10-15.32]; p = 0.001), who had low general health perceptions (AOR: 3.58 [95%CI: 1.20-10.66]; p = 0.021), and who had high distress (AOR: 3.32 [95%CI: 1.19-9.26]; p = 0.022). This study documents several modifiable risk factors for nonadherence in a clinic population of HIV-infected Indians with substantial HAART experience. Further targeted culturally specific interventions are needed that address barriers to optimal adherence.

Association between placental morphology and childhood systolic blood pressure

We tested hypotheses that disproportionately large placental size and vascular lesions were associated with high systolic blood pressure (SBP); and these associations might be more evident with age. The sample included 13 273 of 40 666 full-term singletons in the Collaborative Perinatal Project. Placentas were examined by pathologists blinded of pregnancy courses and outcomes. The 4-month and 7-year SBPs were measured with palpation and auscultation methods, respectively. We found that placental weight (adjusted mean difference corresponding to an increase by 1 SD 0.50 [95% CI, 0.33 to 0.68]) and placenta-fetus weight ratio (0.37 [95% CI, 0.19 to 0.54]) was positively associated with 7-year SBP but not associated with 4-month SBP. Placental largest and smallest diameters and area were negatively associated with 4-month SBP but positively with 7-year SBP. Placental thickness was negatively associated with 4-month SBP only. Placental volume was negatively associated with 4-month SBP (-0.60 [95% CI, - 0.85 to -0.35]) but positively associated with 7-year SBP (0.48 [95% CI, 0.30 to 0.67]). Thrombi in cord vessels (adjusted mean difference versus absence 2.73 [95% CI, - 0.03 to 5.50]) and decidual vessels (2.58 [95% CI, 0.24 to 4.91]), villous microinfarcts (1.63 [95% CI, 0.71 to 2.55]), necrosis at the decidual margin (1.57 [95% CI, 0.54 to 2.59]), and basalis (3.44 [95% CI, 1.55 to 5.32]) were associated with higher 4-month SBP only. We conclude that placental inefficiency, reflected by disproportionately large weight and size, predicts long-term blood pressure, whereas vascular resistance and lesions may only influence short-term blood pressure.

Decreased sexual risk behavior in the era of HAART among HIV-infected urban and rural South Africans attending primary care clinics

OBJECTIVE

In light of increasing access to HAART in sub-Saharan Africa, we conducted a longitudinal study to assess the impact of HAART on sexual risk behaviors among HIV-infected South Africans in urban and rural primary care clinics.

DESIGN

Prospective observational cohort.

METHODS

We conducted a cohort study at rural and urban primary care HIV clinics in South Africa consisting of 1544 men and 4719 women enrolled from 2003 to 2010, representing 19703 clinic visits. The primary outcomes were being sexually active, unprotected sex, and more than one sex partner and were evaluated at 6 monthly intervals. Generalized estimated equations assessed the impact of HAART on sexual risk behaviors.

RESULTS

Among 6263 HIV-infected men and women, over a third (37.2%) initiated HAART during study follow-up. In comparison to pre-HAART follow-up, visits while receiving HAART were associated with a decrease in those reporting being sexually active [adjusted odds ratio: 0.86 (95% confidence interval: 0.78-0.95)]. Unprotected sex and having more than one sex partner were reduced at visits following HAART initiation compared to pre-HAART visits [adjusted odds ratio: 0.40 (95% confidence interval: 0.34-0.46) and adjusted odds ratio: 0.20 (95% confidence interval: 0.14-0.29), respectively].

CONCLUSION

Sexual risk behavior significantly decreased following HAART initiation among HIV-infected South African men and women in primary care programs. The further expansion of antiretroviral treatment programs could enhance HIV prevention efforts in Africa.

Does chocolate intake during pregnancy reduce the risks of preeclampsia and gestational hypertension?

PURPOSE

Chocolate consumption is associated with favorable levels of blood pressure and other cardiovascular disease risk markers. We analyzed a prospective cohort study to determine whether regular chocolate intake during pregnancy is associated with reduced risks of preeclampsia and gestational hypertension (GH).

METHODS

Subjects were recruited from 13 prenatal care practices in Connecticut (1988-1991). In-person interviews were administered at <16 weeks' gestation to ascertain risk factors for adverse pregnancy outcomes. Hospital delivery and prenatal records were abstracted to classify preeclampsia (n = 58), GH (n = 158), and normotensive pregnancies (n = 2351). Chocolate consumption (servings/week) during the first and third trimesters was ascertained at initial interview and immediately postpartum, respectively. Consumers of less than 1 serving/week comprised the referent group. Adjusted odds ratios (aORs) were estimated by the use of logistic regression.

RESULTS

Chocolate intake was more frequent among normotensive (80.7%) than preeclamptic (62.5%) or GH women (75.8%), and associated with reduced odds of preeclampsia (first trimester: aOR, 0.55; 95% confidence interval [95% CI], 0.32-0.95; third trimester: aOR, 0.56; 95% CI, 0.32-0.97). Only first trimester intake was associated with reduced odds of GH (aOR,0.65; 95% CI, 0.45-0.87).

CONCLUSIONS

These findings provide additional evidence of the benefits of chocolate. Prospective studies are needed to confirm and delineate protective effects of chocolate intake on risk of preeclampsia.

Mortality of mothers from cardiovascular and non-cardiovascular causes following pregnancy complications in first delivery

The combined effects of preterm delivery, small-for-gestational-age offspring, hypertensive disorders of pregnancy, placental abruption and stillbirth on early maternal death from cardiovascular causes have not previously been described in a large cohort. We investigated the effects of pregnancy complications on early maternal death in a registry-based retrospective cohort study of 782 287 women with a first singleton delivery in Denmark 1978-2007, followed for a median of 14.8 years (range 0.25-30.2) accruing 11.6 million person-years. We employed Cox proportional hazard models of early death from cardiovascular and non-cardiovascular causes following preterm delivery, small-for-gestational-age offspring and hypertensive disorders of pregnancy. We found that preterm delivery and small-for-gestational-age were both associated with subsequent death of mothers from cardiovascular and non-cardiovascular causes. Severe pre-eclampsia was associated with death from cardiovascular causes only. There was a less than additive effect on cardiovascular mortality hazard ratios with increasing number of pregnancy complications: preterm delivery 1.90 [95% confidence intervals 1.49, 2.43]; preterm delivery and small-for-gestational-age offspring 3.30 [2.25, 4.84]; preterm delivery, small-for-gestational-age offspring and pre-eclampsia 3.85 [2.07, 7.19]. Thus, we conclude that, separately and combined, preterm delivery and small-for-gestational-age are strong markers of early maternal death from both cardiovascular and non-cardiovascular causes, while hypertensive disorders of pregnancy are markers of early death of mothers from cardiovascular causes.

Integrated exposure modeling: a model using GIS and GLM

Traffic exhaust is a source of air contaminants that have adverse health effects. Quantification of traffic as an exposure variable is complicated by aerosol dispersion related to variation in layout of roads, traffic density, meteorology, and topography. A statistical model is presented that uses Geographic Information Systems (GIS) technology to incorporate variables into a generalized linear model that estimates distribution of traffic-related pollution. Exposure from a source is expressed as an integral of a function proportional to average daily traffic and a nonparametric dispersion function, which takes the form of a step, polynomial, or spline model. The method may be applied using standard regression techniques for fitting generalized linear models. Modifiers of pollutant dispersion such as wind direction, meteorology, and landscape features can also be included. Two examples are given to illustrate the method. The first employs data from a study in which NO(2) (a known pollutant from automobile exhaust) was monitored outside of 138 Connecticut homes, providing a model for estimating NO(2) exposure. In the second example, estimated levels of nitrogen dioxide (NO(2)) from the model, as well as a separate spatial model, were used to analyze traffic-related health effects in a study of 761 infants.