Associations of per- and polyfluoroalkyl substances with uterine leiomyomata incidence and growth: a prospective ultrasound study.

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are endocrine-disrupting chemicals used in commercial and consumer products. OBJECTIVE: We evaluated PFAS exposure in relation to incidence and growth of uterine leiomyomata (UL), hormone-dependent neoplasms that are associated with severe gynecologic morbidity. METHODS: We studied 1158 participants in the Study of Environment, Lifestyle, and Fibroids, a Detroit-based prospective cohort study of Black females aged 23-35 years at enrollment (2010-2012). At enrollment and four subsequent visits during 10 years of follow-up, participants attended in-person clinic visits, completed questionnaires, provided non-fasting blood samples, and underwent ultrasound for UL detection. We quantified 7 PFAS in baseline plasma samples using mass spectrometry. We used Cox regression and probit Bayesian kernel machine regression to estimate individual and joint effects of PFAS on UL incidence. We fit linear mixed models to estimate effects of individual PFAS on UL growth. We stratified by parity, an important route of PFAS elimination and determinant of UL. RESULTS: In individual PFAS analyses, we observed inverse associations for perfluorodecanoate (PFDA; ≥0.3 vs. <0.2 ng/ml: hazard ratio [HR] = 0.74; 95% confidence interval [CI]: 0.54-1.00) and perfluoroundecanoate (detected vs. non-detected: HR = 0.78; 95% CI: 0.61-1.01) and a weak positive association for perfluorohexane sulfonate (≥1 vs. <0.6 ng/ml: HR = 1.17; 95% CI: 0.85-1.61), while perfluorooctane sulfonate, perfluorooctanoate, perfluorononanoate (PFNA), and 2-N-methyl-perfluorooctane sulfonamido acetate (MeFOSAA) showed little association with UL incidence. The PFAS mixture was inversely associated with UL incidence, a finding driven by MeFOSAA and PFDA; however, PFNA was positively associated with UL incidence. The inverse association for PFDA and positive association for PFNA were stronger among nulliparous participants. Most PFAS showed slight inverse associations with UL growth. IMPACT STATEMENT: In this prospective ultrasound study of 1158 Black females aged 23-35 years at enrollment, we conducted a mixtures analysis to account for co-pollutant confounding and interaction. MeFOSAA and PFDA concentrations were inversely associated with UL incidence, while PFNA concentrations were positively associated with UL incidence. Concentrations of most PFAS were associated with decreased UL growth. This study contributes data to the sparse literature on PFAS exposure and UL development.

Racial disparities between measures of area deprivation and financial toxicity, and uterine volume in myomectomy patients.

BACKGROUND: At time of myomectomy, a surgical procedure to remove uterine fibroids, Black women tend to have larger uteri than White women. This makes Black patients less likely to undergo a minimally invasive myomectomy which has been shown to have less postoperative pain, less frequent postoperative fever and shorter length of stay compared to abdominal myomectomies. The associations between individual financial toxicity and community area deprivation and uterine volume at the time of myomectomy have not been investigated. METHODS: We conducted a secondary data analysis of patients with fibroids scheduled for myomectomy using data from a fibroid treatment registry in [location]. We used validated measures of individual-level Financial Toxicity (higher scores = better financial status) and community-level Area Deprivation (ADI, high scores = worse deprivation). To examine associations with log transformed uterine volume, we used linear regression clustered on race (Black vs. White). RESULTS: Black participants had worse financial toxicity, greater deprivation and larger uterine volumes compared with White participants. A greater Financial Toxicity score (better financial status) was associated with lower uterine volume. For every 10 unit increase in Financial Toxicity, the mean total uterine volume decreased by 9.95% (Confidence Interval [CI]: -9.95%, -3.99%). ADI was also associated with uterine volume. A single unit increase in ADI (worse deprivation) was associated with a 5.13% (CI: 2.02%, 7.25%) increase in mean uterine volume. CONCLUSION: Disproportionately worse Financial Toxicity and ADI among Black patients is likely due to structural racism - which now must be considered in gynecologic research and practice. TRIAL REGISTRATION: Not applicable.

The impact of prenatal dog keeping on infant gut microbiota development.

INTRODUCTION: Prenatal and early-life dog exposure has been linked to reduced childhood allergy and asthma. A potential mechanism includes altered early immune development in response to changes in the gut microbiome among dog-exposed infants. We thus sought to determine whether infants born into homes with indoor dog(s) exhibit altered gut microbiome development. METHODS: Pregnant women living in homes with dogs or in pet-free homes were recruited in southeast Michigan. Infant stool samples were collected at intervals between 1 week and 18 months after birth and microbiome was assessed using 16S ribosomal sequencing. Perinatal maternal vaginal/rectal swabs and stool samples were sequenced from a limited number of mothers. Mixed effect adjusted models were used to assess stool microbial community trajectories comparing infants from dog-keeping versus pet-free homes with adjustment for relevant covariates. RESULTS: Infant gut microbial composition among vaginally born babies became less similar to the maternal vaginal/rectal microbiota and more similar to the maternal gut microbiota with age-related accumulation of bacterial species with advancing age. Stool samples from dog-exposed infants were microbially more diverse (p = .041) through age 18 months with enhanced diversity most apparent between 3 and 6 months of age. Statistically significant effects of dog exposure on ß-diversity metrics were restricted to formula-fed children. Across the sample collection period, dog exposure was associated with Fusobacterium genera enrichment, as well as enrichment of Collinsella, Ruminococcus, Clostridaceae and Lachnospiraceae OTUs. CONCLUSION: Prenatal/early-life dog exposure is associated with an altered gut microbiome during infancy and supports a potential mechanism explaining lessened atopy and asthma risk. Further research directly linking specific dog-attributable changes in the infant gut microbiome to the risk of allergic disorders is needed.

Transcriptome and DNA methylome analyses reveal underlying mechanisms for the racial disparity in uterine fibroids.

Uterine fibroids (leiomyomas) affect Black women disproportionately compared with women of other races and ethnicities in terms of prevalence, incidence, and severity of symptoms. The causes of this racial disparity are essentially unknown. We hypothesized that myometria of Black women are more susceptible to developing fibroids, and we examined the transcriptomic and DNA methylation profiles of myometria and fibroids from Black and White women for comparison. Myometrial samples cluster by race in both their transcriptome and DNA methylation profiles, whereas fibroid samples only cluster by race in the latter. More differentially expressed genes (DEGs) were detected in the Black and White myometrial sample comparison than in the fibroid comparison. Leiomyoma gene set expression analysis identified 4 clusters of DEGs, including a cluster of 24 genes with higher expression in myometrial samples from Black women. One of the DEGs in this group, von Willibrands factor (VWF), was significantly hypomethylated in both myometrial samples from Black women and in all fibroids at 2 CpG probes that are near a putative enhancer site and that are correlated with VWF expression levels. These results suggest that the molecular basis for the disparity in fibroid disease between Black and White women could be found in the myometria before fibroid development and not in the fibroids themselves.

Anxiety, Depression, and Quality of Life After Procedural Intervention for Uterine Fibroids.

Background: Quality of life (QOL) and psychological health has been reported to be decreased among women with gynecological conditions such as uterine fibroids (UFs). Materials and Methods: Women enrolled in the Comparing Options for Management: PAtient-centered REsults for Uterine Fibroids (COMPARE-UF) registry, receiving procedural therapy for symptomatic UFs, were eligible for this analysis if they completed a series of health-related QOL surveys administered at three time points (baseline, 6-12 weeks postprocedure, and 1 year postprocedure; n = 1486). Ethical approval for this study was obtained at each recruiting site and the coordinating center (NCT02260752, clinicaltrials.gov). Results: More than 26% (n = 393) of women reported moderate anxiety/depression on the baseline anxiety/depression domain of the Euro-QOL 5-dimension instrument. At both the 6-12 weeks and 1-year postprocedural follow-up, there was significant improvement in the UF QOL symptom severity score (p < 0.001, p < 0.001), the total UF symptom QOL score (p < 0.001, p < 0.001), and the Euro-QOL 5-dimension visual analog scale (p < 0.001, p = 0.004) compared with the preprocedural baseline scores. The reporting of anxiety/depression decreased by 66.4% among women who were at baseline, whereas 5.6% of women previously reporting no anxiety/depression reported anxiety/depression at the 1-year follow-up. Conclusion: UF symptoms were more severe among women reporting anxiety/depression at baseline. At the 1-year follow-up, health-related QOL scores improved among all women and the prevalence of anxiety/depression decreased in most, but not all women, whereas severity of anxiety/depression worsened in a small percentage of women (5.6%). Overall, these results suggest that UF treatment improves symptoms of anxiety/depression associated with symptomatic UFs.

Correlates of plasma concentrations of per- and poly-fluoroalkyl substances among reproductive-aged Black women.

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals used in commercial and consumer goods. Black women are underrepresented in studies of PFAS exposure. METHODS: We performed a cross-sectional analysis of correlates of plasma PFAS concentrations among 1499 Black women aged 23-35 participating in the Study of Environment, Lifestyle, and Fibroids (SELF), a Detroit-based cohort study. At baseline (2010-2012), participants provided questionnaire data on socio-demographics; behaviors; diet; and menstrual, contraceptive, and reproductive histories. Using mass spectrometry in non-fasting plasma samples collected at enrollment, we quantified several PFAS, including perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnDA), and 2-N-methyl-perfluorooctane sulfonamido acetate (MeFOSAA). We used linear regression to calculate percentage differences (%D) and 95 % confidence intervals (CIs) for associations between selected correlates and PFAS concentrations, adjusting for all other correlates. RESULTS: PFHxS, PFOS, PFOA, and PFNA were detected in ≥97 % of women; PFDA in 86 %; MeFOSAA in 70 %; and PFUnDA in 52 %. Age, income, education, and intakes of water, alcohol, and seafood were positively associated with several PFAS. Current smoking was positively associated with MeFOSAA. Body mass index was inversely associated with most PFAS, except PFHxS. Strong inverse associations (%D; 95 % CI) were observed between parity (≥3 vs. 0 births) and PFHxS (-34.7; -43.0, -25.1) and PFOA (-33.1; -39.2, -26.3); breastfeeding duration (≥6 months vs. nulliparous) and PFOA (-31.1; -37.8, -23.7), PFHxS (-24.2; -34.5, -12.3), and PFOS (-18.4; -28.3, -7.1); recent birth (<2 years ago vs. nulliparous) and PFOA (-33.1; -39.6, -25.8), PFHxS (-29.3; -39.0, -18.1), PFNA (-25.2; -32.7, -16.8), and PFOS (-18.3; -28.3, -6.9); and intensity of menstrual bleed (heavy vs. light) and PFHxS (-18.8; -28.3, -8.2), PFOS (-16.4; -24.9, -7.1), PFNA (-10.5; -17.8, -2.6), and PFOA (-10.0; -17.2, -2.1). Current use of depot medroxyprogesterone acetate (DMPA) was positively associated with PFOS (20.2; 1.4, 42.5), PFOA (16.2; 1.5, 33.0), and PFNA (15.3; 0.4, 32.4). CONCLUSIONS: Reproductive factors that influence PFAS elimination showed strong associations with several PFAS (reduced concentrations with parity, recent birth, lactation, heavy menstrual bleeding; increased concentrations with DMPA use).

Introduction of a community health worker diabetes coach improved glycemic control in an urban primary care clinic.

The burden of diabetes is higher in urban areas and among racial and ethnic minorities. The purpose of this research was to evaluate the effectiveness of extending a diabetes intervention program (DIP) by engaging a team, including a community health worker (CHW), to provide care for patients to meet glycemic control, specifically in a predominantly urban, minority patient population. The DIP enrolled diabetic patients from an internal medicine clinic. A CHW facilitated the collection of glucose meter readings. The CHW coached patients on glycemic control while the CHW's registered nurse partner titrated the patient's recommended insulin dose. Subsequent HbA1c values for participants were compared to those seen at the same clinic who were not enrolled. The DIP was deployed for nine months. One hundred forty-four patients were enrolled in the DIP and 348 patients constituted the comparator group. Ninety-three DIP participants had pre- and post-intervention HbA1c values and were compared to 348 non-DIP participants. Propensity score weighted adjusted analyses suggest that participants were more likely to reduce their HbA1c values by at least 1.0% and have HbA1c values of less than 8.0% (64 mmol/mol) than non-participants (adjusted odds ratio = aOR = 1.47, 95% CI 1.26-1.71, and aOR = 1.23, 95% CI 1.06-1.43, respectively). CHW coaches as part of a team in a clinical setting improved glycemic control in a predominantly urban, minority patient population.

Dietary Fat Intake and Risk of Uterine Leiomyomata: A Prospective Ultrasound Study.

Uterine leiomyomata (UL) are associated with severe reproductive morbidity and are the primary indication for hysterectomy in the United States. A recent prospective cohort study of Black women reported positive associations between intakes of marine-sourced ω-3 fatty acids and UL risk. We examined whether intakes of dietary fat were associated with UL incidence in a 5-year prospective study of premenopausal Black women living in Detroit who underwent serial ultrasound. At baseline (2010-2012) and 20, 40, and 60 months of follow-up, participants underwent transvaginal ultrasound. Among 1,171 UL-free women at baseline, incident UL were detected in 277 women. Cox regression was used to estimate hazard ratios and 95% confidence intervals for the association of dietary fat and UL incidence. Intakes of total fat and saturated, monounsaturated, polyunsaturated, and trans-fat were not appreciably associated with UL incidence. Intake of the marine ω-3 polyunsaturated fatty acid, docosahexaenoic acid, was associated with 49% higher UL incidence (quartile 4 vs. 1: hazard ratio = 1.49, 95% confidence interval: 1.04, 2.14; P for trend = 0.01). Intakes of total marine ω-3 polyunsaturated fatty acids were similarly associated with elevated UL incidence (hazard ratio = 1.35, 95% confidence interval: 0.94, 1.93; P for trend = 0.03). It remains unclear whether the fatty acids or persistent environmental pollutants drive the association.

Association between asthma symptom scores and perceived stress and trait anxiety in adolescents with asthma.

Background: Emotional disorders, including depression and anxiety, are more prevalent in individuals with asthma than in the general population and are associated with poor asthma outcomes. Identification of patients with increased levels of stress and anxiety may be helpful when treating asthma and during asthma counseling. Objective: To further characterize the relationship between asthma symptoms and perceived stress and trait anxiety in an adolescent population. Methods: Adolescents (N = 335) ages 14-17 years were recruited to examine the effect of stress on health measures. They were included in the present analysis if they reported current asthma, defined as self-reported clinician-diagnosed asthma plus one or more episodes of asthma in the past year. Asthma symptoms were assessed on a 7-point scale by using a standardized questionnaire that targets nocturnal awakening due to asthma, symptoms on awakening, activity limitation, shortness of breath, time spent wheezing, and short-acting bronchodilator use. Stress was measured by using the Perceived Stress Scale (PSS), and trait anxiety was measured by using the State-Trait Anxiety Inventory. Linear regression was used to associate asthma symptoms with PSS and trait anxiety. Results: Thirty-eight adolescents (11.3%), with mean ± standard deviation age 16.7 ± 0.9 years, reported current asthma. Four of the six asthma symptom assessments had significant associations with PSS: symptoms on awakening (ß = 4.82, p < 0.001), nocturnal awakening due to asthma (ß = 4.47, p < 0.001), activity limitation (ß = 2.78, p = 0.005), and shortness of breath (ß = 1.73, p = 0.014). These associations remained significant after adjusting for gender, race, and the body mass index percentile. Trait anxiety had significant associations with nocturnal awakening (ß = 9.28, p = 0.002) and symptoms on awakening (ß = 8.74, p = 0.002). Associations remained significant after adjusting for gender, race, and body mass index percentile. Conclusion: Asthma symptom severity is associated with increased perceived stress and trait anxiety. Adolescents with asthma may represent a population that is particularly vulnerable to perceived stress and anxiety, which highlights the importance of considering these factors in asthma counseling.

Comparative effectiveness of hysterectomy versus myomectomy on one-year health-related quality of life in women with uterine fibroids.

OBJECTIVE: To compare long-term health-related quality of life (HRQOL) 1 year after hysterectomy or myomectomy for treatment of uterine fibroids (UFs) and to determine whether route of procedure, race, or age affected improvements in HRQOL. DESIGN: Prospective cohort study. SETTING: Eight clinical sites throughout the United States. PATIENT(S): A total of 1,113 premenopausal women with UFs who underwent hysterectomy or myomectomy as part of Comparing Options for Management: Patient-Centered Results for Uterine Fibroids. INTERVENTION(S): None. MAIN OUTCOME MEASURE (S): Self-reported HRQOL measures including Uterine Fibroid Symptom Quality of Life, the European QOL 5 Dimension Health Questionnaire, and the visual analog scale at baseline and 1-year after hysterectomy or myomectomy. RESULT (S): Hysterectomy patients were older with a longer history of symptomatic UF compared with myomectomy patients. There were no differences in baseline HRQOL. After adjustment for baseline differences between groups, compared with myomectomy, patients' HRQOL (95% confidence interval [CI], 5.4, 17.2) and symptom severity (95% CI, -16.3, -8.8) were significantly improved with hysterectomy. When stratified across race/ethnicity and age, hysterectomy had higher HRQOL scores compared with myomectomy. There was little difference in HRQOL (95% CI, 0.1 [-9.5, 9.6]) or symptom severity (95% CI, -3.4 [-10, 3.2]) between abdominal hysterectomy and abdominal myomectomy. CONCLUSION (S): HRQOL improved in all women 1 year after hysterectomy or myomectomy. Hysterectomy patients reported higher HRQOL summary scores compared with myomectomy patients. When stratified by route, minimally invasive hysterectomy had better HRQOL scores than minimally invasive myomectomy. There was little difference in scores with abdominal approaches.

The Comparing Options for Management: PAtient-centered REsults for Uterine Fibroids (COMPARE-UF) registry: rationale and design.

BACKGROUND: Uterine fibroids are common in premenopausal women, yet comparative effectiveness research on uterine fibroid treatments is rare. OBJECTIVE: The purpose of this study was to design and establish a uterine fibroid registry based in the United States to provide comparative effectiveness data regarding uterine fibroid treatment. STUDY DESIGN: We report here the design and initial recruitment for the Comparing Options for Management: Patient-centered REsults for Uterine Fibroids (COMPARE-UF) registry (Clinicaltrials.gov, NCT02260752), funded by the Agency for Healthcare Research and Quality in collaboration with the Patient-Centered Outcomes Research Institute. COMPARE-UF was designed to help answer critical questions about treatment options for women with symptomatic uterine fibroids. Women who undergo a procedure for uterine fibroids (hysterectomy, myomectomy [abdominal, hysteroscopic, vaginal, and laparoscopic/robotic], endometrial ablation, radiofrequency fibroid ablation, uterine artery embolization, magnetic resonance-guided focused ultrasound, or progestin-releasing intrauterine device insertion) at 1 of the COMPARE-UF sites are invited to participate in a prospective registry with 3 years follow up for postprocedural outcomes. Enrolled participants provide annual follow-up evaluation through an online portal or through traditional phone contact. A central data abstraction center provides information obtained from imaging, operative or procedural notes, and pathology reports. Women with uterine fibroids and other stakeholders are a key part of the COMPARE-UF registry and participate at all points from study design to dissemination of results. RESULTS: We built a network of 9 clinical sites across the United States with expertise in the care of women with uterine fibroids to capture geographic, racial, ethnic, and procedural diversity. Of the initial 2031 women who were enrolled in COMPARE-UF, 42% are self-identified as black or African American, and 40% are ≤40 years old, with 16% of participants <35 years old. Women who undergo myomectomy comprise the largest treatment group at 46% of all procedures, with laparoscopic or robotic myomectomy comprising the largest subset of myomectomies at 19% of all procedures. Hysterectomy is the second most common treatment within the registry at 38%. CONCLUSION: In response to priorities that were identified by our patient stakeholders, the initial aims within COMPARE-UF will address how different procedures that are used to treat uterine fibroids compare in terms of long-lasting symptom relief, potential for recurrence, medical complications, improvement in quality of life and sexual function, age at menopause, and fertility and pregnancy outcomes. COMPARE-UF will generate evidence on the comparative effectiveness of different procedural options for uterine fibroids and help patients and their caregivers make informed decisions that best meet an individual patient's short- and long-term preferences. Building on this infrastructure, the COMPARE-UF team of investigators and stakeholders, including patients, collaborate to identify future priorities for expanding the registry, such as assessing the efficacy of medical therapies for uterine fibroids. COMPARE-UF results will be disseminated directly to patients, providers, and other stakeholders by traditional academic pathways and by innovative methods that include a variety of social media platforms. Given demographic differences among women who undergo different uterine fibroid treatments, the assessment of comparative effectiveness for this disease through clinical trials will remain difficult. Therefore, this registry provides optimized evidence to help patients and their providers better understand the pros and cons of different treatment options so that they can make more informed decisions.

Dog allergen levels in homes with hypoallergenic compared with nonhypoallergenic dogs.

BACKGROUND: Despite the public interest in hypoallergenic dogs, few scientific, including epidemiological studies have attempted to evaluate claims of hypoallergenicity. This study was designed to determine whether dog breeds reported as hypoallergenic correspond to lower dog allergen in the home versus nonhypoallergenic dogs. METHODS: A web search was conducted to identify breeds cited as hypoallergenic. Four separate classification schemes using combinations of purebred and mixed breed dogs were used to compare the levels of Canis familiaris 1 in dust samples collected from homes with hypoallergenic versus nonhypoallergenic dogs from an established birth cohort. RESULTS: No classification scheme showed that the level of dog allergen in homes with hypoallergenic dogs differed from other homes. CONCLUSION: Dog-allergic individuals should have access to scientifically valid information on the level of allergen shedding of different breeds of dogs.

Variation of dust endotoxin concentrations by location and time within homes of young children.

Endotoxin may affect the development of allergic disease in childhood but little is known about endotoxin variation within homes. We sought to determine endotoxin concentration agreement within homes when five locations were each sampled twice 5 months apart. Endotoxin was measured using the recombinant Limulus factor C assay in dust samples from 585 homes of children enrolled in a prospective study and again in 335 homes 5 months later. The five locations sampled in each home were the child's bedroom floor, child's bed, mother's bedroom floor, mother's bed and living room floor. Concentrations of 4 allergens (Can f 1, Fel d 1, Der f 1 and Bla g 2) were also measured from the child's bedroom floor. In pair-wise comparisons, endotoxin concentrations in all locations within each home were significantly different from all other locations (p < 0.001) except for the child's and mother's bedroom floors (p = 0.272). Spearman correlations between endotoxin concentrations from the different locations were all statistically significant (p < 0.05) but of modest magnitude (r = 0.24-0.54). Similarly, correlations at each site over the 5 month observation interval were statistically significant but modest (r = 0.17-0.44). Pets and season of the year did not affect correlations, although correlations were lower if the floor was not carpeted. Endotoxin concentrations at all locations were minimally correlated with allergen concentrations in both negative and positive directions (r = -0.12 to 0.12). We conclude that a single measurement of endotoxin from a home dust sample provides an imprecise estimate of dust endotoxin concentrations in other locations within the home and over a relatively short observation interval.

Influence of dose and frequency of antigen injection on IgE development in young children: a comparison of fire ant stings and tetanus immunizations.

BACKGROUND: Previous studies suggest that small antigen doses given frequently are more likely to induce IgE production than are large antigen doses given infrequently. OBJECTIVE: To compare the prevalence of antitetanus IgE resulting from the relatively large dose of tetanus toxoid delivered by standard immunizations at 2, 4, 6, and 18 months of age with the previously reported prevalence of anti-fire ant venom IgE resulting from the relatively small dose of venom delivered sporadically by accidental fire ant stings in children younger than 5 years. METHODS: This study uses previously published data on the prevalence of IgE antibodies to imported fire ant venom among children living in an imported fire ant endemic area of Georgia and antitetanus IgE measurements of children recruited between August 1, 2003, and December 30, 2007, as part of the Wayne County Health, Environment, Allergy, and Asthma Longitudinal Study in Michigan, where there are no imported fire ants. The prevalence of anti-fire ant venom IgE antibodies was compared with the prevalence of antitetanus IgE antibodies in these 2 cohorts of children. RESULTS: The reported prevalence of IgE to fire ant venom among 42 children 2 to 5 years old was 57.1% using a cutoff of 0.1 IU/mL and 35.7% using a cutoff of 0.35 IU/mL. The prevalence of antitetanus IgE in 395 children 2 years old was 52.9% using a cutoff of 0.1 IU/mL and 42.7% using a cutoff of 0.35 IU/mL. The proportion of children with detectable anti-fire ant venom IgE was not statistically significantly different from the proportion of those with antitetanus IgE at either cutoff level (P = .74 and .50 at 0.1 and 0.35 IU/mL, respectively). CONCLUSIONS: The relatively large dose of tetanus toxoid delivered 4 times during the first 24 months of life produces detectable tetanus specific IgE antibodies as frequently as the smaller doses of venom delivered sporadically by fire ant stings in young children.

Differences in total and allergen specific IgE during pregnancy compared with 1 month and 1 year post partum.

BACKGROUND: Pregnancy alters the function of many body systems, including the immune system. However, little is known regarding the effect of pregnancy on maternal IgE levels or atopy. OBJECTIVE: To determine whether pregnancy consistently influences serum levels of total or allergen specific IgE. METHODS: Blood samples were obtained from 764 women during the third trimester of pregnancy and 1 month post partum. A third sample was obtained from 106 of these women 1 year post partum. Samples were analyzed for total and specific IgE to 8 regionally common allergens using a commercially available system. Sensitization was defined as an allergen specific IgE level of 0.35 kU of allergen per liter or higher to any allergen. RESULTS: Total IgE increased significantly post partum, both at 1 month (40.36 vs 35.37 IU/mL intrapartum; P = .001) and at 1 year (44.97 vs 37.00 IU/mL intrapartum; P = .005). Allergen specific IgE decreased significantly at 1 month for cat, dog, ragweed, timothy grass, and egg (P = .001 to P = .02) but not for dust mite, cockroach, or Alternaria (P = .15 to P = .90). Similar patterns of change in total and specific IgE were seen at 1 year. However, on average, only 3.5% of participants changed sensitization status to the individual allergens studied during the 1 year of observation. CONCLUSIONS: Compared with intrapartum levels, total IgE levels increased significantly at 1 month and 1 year post partum. Conversely, at the same time points, IgE levels specific for common allergens significantly declined to most but not all allergens. Few women changed their sensitization status over 1 year.

Risk factors associated with transient wheezing in young children.

Transient wheezing in young children has been reported to be independent of atopy. Although persistence of early wheezing has been associated with factors related to allergy in multiple studies, transient wheezing has not been similarly studied. The Childhood Allergy Study birth cohort was the source of these data. Transient wheezing was defined as history of wheezing in the past 12 months at ages 1, 2, and/or 4 years, but not at 6 years, and evaluated in relationship to aeroallergen-specific circulating IgE and positive skin testing as markers of an atopic profile. Testing for IgE and skin-prick testing to dust mites, dogs, cats, ragweed, and timothy were performed at the age of 6 years. Other variables in logistic regression analyses were sex; breast-feeding; birth order; parental allergy and smoking history; and household pets, daycare, fever, and antibiotic use in the 1st year of life. Of 372 children, 128 (34.4%) experienced transient wheezing and 175 (47.0%) never wheezed. Atopy was not associated with transient wheezing (adjusted odds ratio for a positive allergen-specific IgE test = 1.2, p = 0.66; skin-prick test = 0.8, p = 0.47). Boys were more likely to be transient wheezers (adjusted relative risk [RR] = 1.7; 95% confidence interval [CI], 1.1-2.8; p = 0.018). Transient wheeze was associated with antibiotic treatment in the first 6 months of life (adjusted RR = 1.6; 95% CI, 1.0-2.6; p = 0.048). We confirm previous observations that transient wheezing in young children is not associated with an atopic predisposition.