Altered COVID-19 immunity in children with asthma by atopic status.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes a spectrum of clinical outcomes that may be complicated by severe asthma. Antiviral immunity is often compromised in patients with asthma; however, whether this is true for SARS-CoV-2 immunity and children is unknown. Objective: We aimed to evaluate SARS-CoV-2 immunity in children with asthma on the basis of infection or vaccination history and compared to respiratory syncytial viral or allergen (eg, cockroach, dust mite)-specific immunity. Methods: Fifty-three children from an urban asthma study were evaluated for medical history, lung function, and virus- or allergen-specific immunity using antibody or T-cell assays. Results: Polyclonal antibody responses to spike were observed in most children from infection and/or vaccination history. Children with atopic asthma or high allergen-specific IgE, particularly to dust mites, exhibited reduced seroconversion, antibody magnitude, and SARS-CoV-2 virus neutralization after SARS-CoV-2 infection or vaccination. TH1 responses to SARS-CoV-2 and respiratory syncytial virus correlated with antigen-respective IgG. Cockroach-specific T-cell activation as well as IL-17A and IL-21 cytokines negatively correlated with SARS-CoV-2 antibodies and effector functions, distinct from total and dust mite IgE. Allergen-specific IgE and lack of vaccination were associated with recent health care utilization. Reduced lung function (forced expiratory volume in 1 second ≤ 80%) was independently associated with (SARS-CoV-2) peptide-induced cytokines, including IL-31, whereas poor asthma control was associated with cockroach-specific cytokine responses. Conclusion: Mechanisms underpinning atopic and nonatopic asthma may complicate the development of memory to SARS-CoV-2 infection or vaccination and lead to a higher risk of repeated infection in these children.

Pesticide exposure and asthma morbidity in children residing in urban, multi-family housing.

BACKGROUND: Children are potentially more susceptible to the adverse effects of pesticides due to more sensitive organ systems and lower capacity to metabolize and eliminate chemicals compared to adults. The health risks are particularly concerning children with asthma, living in low-income neighborhoods in multi-family housing because of their impaired respiratory health, and factors associated with low-income, multi-family environments. OBJECTIVE: To assess the association between pesticide exposure and asthma morbidity among children 7-12 years residing in low-income, multi-family housing. METHODS: The concentrations of seven urinary pesticide biomarkers: 3,5,6-trichloro-2-pyridinol (TCPy), 2-isopropyl-4-methyl-6-hydroxypyrimidine, para-nitrophenol (PNP), 3-phenoxybenzoic acid (3-PBA), 4-fluoro-3-phenoxybenzoic acid, trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropane-1-carboxylic acid, and 2,4-dichlorophenoxyacetic acid (2,4-D) were measured. Children (n = 162) were followed for one year with three measures of pesticides biomarkers. Associations between individual biomarkers and asthma attack, asthma related health care utilization, and fraction of exhaled nitric oxide (FeNO), adjusting for demographic and household factors were examined with Generalized Estimating Equations (GEE). Weighted Quantile Sum (WQS) regression was used to examine the effect of pesticide mixture on asthma attacks and asthma-related health care utilization (HCU). RESULTS: In adjusted GEE models, positive non-significant associations were found between PNP and HCU (adjusted Odds Ratio(aOR):2.05 95% CI:0.76-5.52) and null associations for 3-PBA and HCU (aOR:1.07 95% CI: 0.88-1.29). Higher concentrations of PNP and 2,4-D were associated with significantly lower FeNO levels (PNP: -17.4%; 2,4-D:-19.74%). The mixture was positively associated with HCU in unadjusted (OR: 1.56 97.5% CI: 1.08-2.27) but not significant in adjusted models (aOR: 1.40 97.5% CI: .86-2.29). The non-specific pyrethroid biomarker 3-PBA at baseline contributed the greatest weight to the index (45%). SIGNIFICANCE: There were non-significant associations between pesticide biomarkers and respiratory outcomes in children with asthma. There was a suggestive association between urinary pesticide biomarkers and HCU. Further studies with larger sample sizes could help to confirm these findings. IMPACT STATEMENT: Pesticide exposure among children in the urban environment is ubiquitous and there is a dearth of information on the impact of low-level chronic exposure in vulnerable populations. This study suggested that pesticide exposure at concentrations below the national average may not affect asthma morbidity in children. However, different biomarkers of pesticides showed different effects, but the mixture suggested increasing pesticide exposure results in asthma related HCU. The results may show that children with asthma may be at risk for negative health outcomes due to pesticides and the need to further examine this relationship.

Elevation of Serum Copper in the New Orleans Bariatric Clinic Population: the Norm or Geographically Localized Findings?

INTRODUCTION: Circulating micronutrient levels of both serum copper and zinc have been studied to varying degrees in both the general public and patients having undergone bariatric surgery. According to the 2019 ASMBS clinical guidelines, copper supplementation is recommended for patients undergoing metabolic surgery, especially after Roux-en-Y gastric bypass and duodenal switch. Copper excess has not been previously reported to any significant degree in any population. OBJECTIVE: In this study, we investigate an elevated serum copper level in the pre-surgical intervention population of the Bariatric Center of the University Medical Center-New Orleans, a primary safety net hospital for the state of Louisiana. METHODS: Five hundred five consecutive patients from the bariatric surgery undergoing a workup for surgical intervention were assessed. Patients were included regardless of whether they proceeded to surgery. The study was conducted as a retrospective review of deidentified data that was collected as part of our routine workup for bariatric surgery. RESULTS: The study population of the clinic consisted of a mean BMI of approximately 50 kg/m2, with 91% of the population reporting female and 69% recording an African American race. It was discovered in this population that 26% of the patients had an elevated copper level of > 155 mcg/dl. Additional analysis was performed attempting to elucidate an environmental role in the elevation by qualitative analysis of patient's location of residence using reported home address. Additional variables were studied as well including serum zinc concentration, age, BMI, and race to address any correlative variables with our findings. CONCLUSION: This study identifies an elevated serum copper concentration in a pre-intervention underserved bariatric center population positively associated with BMI, female gender, and African American race. Additional studies will be necessary to see if these trends are also apparent in normal weight controls, or if weight loss influences copper levels. Pre-existing serum copper deficiencies may be more prevalent in the bariatric populations than previously believed. Increased serum copper in this population was positively associated with increased BMI, age, and female gender compared to that of the male group. Increased serum copper was also associated more closely with African American ethnicity compared to Caucasian patients.

Knowledge, attitudes, and practices concerning cockroach exposure among caregivers of children with asthma.

BACKGROUND: Cockroach allergen is one of the most important asthma triggers for children. There is an extensive body of research on interventions to reduce exposure. However, adherence to these interventions is low. Insight into the knowledge, attitudes, and practices (KAP) associated with cockroach remediation is needed. We assessed KAP using the Health Beliefs Model (HBM) as a framework for predicting behavior. This study aimed to assess the socio-demographic and psycho-social characteristics associated with cockroach KAP and to quantify the relationship between KAP and number of cockroaches in the home. METHODS: To identify factors associated with cockroach KAP a cross-sectional study was conducted using a structured questionnaire administered to caregivers of children with asthma in New Orleans, Louisiana. Positive scores in each metric of the KAP signified better cockroach knowledge, increased concern about cockroaches' impact on health (attitudes), and participation in recommended cockroach remediation practices (practices). To evaluate cockroach KAP scores as a predictor of cockroach exposure in the home, a cohort study was conducted among a sub-sample of participants. RESULTS: Fifty-six caregivers participated in the study. Participants had positive scores on all subscales of KAP with knowledge having a lower score compared to attitudes and practices. Cockroach knowledge was inversely correlated with age at asthma diagnosis (ρ = - 0.36, p = 0.01). Caregivers identifying as black/African American had higher cockroach knowledge scores compared to other races (Median: 6.0 v 3.0; p = 0.05). Caregivers other than mothers had higher cockroach attitude scores (Median 6.5 v 4.0; p = 0.003) and total KAP scores (Median 18.0 v 14.0; p = 0.05). Twenty-six participants completed the cohort study. Cockroach exposure was not significantly associated with higher cockroach knowledge, cockroach practice, or total KAP score. For attitude scores, participants in the highest quartile had significantly lower exposure (ß: -1.96, 95% CI: - 3.50 - 0.42) compared to those in the lowest quartile (p = 0.01). CONCLUSIONS: Different socio-demographic and psycho-social factors were associated with the components of cockroach KAP. Greater concern about cockroaches (attitude) was significantly associated with reduced cockroach exposure. This highlights the importance of identifying the key elements of caregiver KAP to improve cockroach remediation among caregivers of children with asthma.

Cockroach exposure and perceived stress interact to predict clinical outcomes in childhood asthma.

BACKGROUND: Nonpharmacologic interventions for asthma management rely on identification and mitigation of important asthma triggers. Cockroach exposure is strongly associated with asthma morbidity. It is also associated with stress, another risk factor for asthma. Despite high prevalence of both in vulnerable populations, the impact of joint exposure has not been examined. METHODS: Participants included 173 children with asthma in New Orleans, Louisiana. Cockroach exposure was based on visual inspection using standard protocols. Caregiver stress was measured using Cohen's 4-item Perceived Stress Scale. Outcomes included unscheduled clinic or emergency department (ED) visits, hospitalization, and pulmonary function. Multivariable logistic regression was performed to assess independent effects of the exposure on the outcome and effect modification was examined in stratified analysis based on stress. Path analysis to explore the mediation effect by stress was performed using a probit link with parameters based on Bayes' method with non-informative priors. RESULTS: Adjusting for stress and other covariates, cockroach exposure was associated with unscheduled clinic/ED visits (aOR = 6.2; 95% CI 1.8, 21.7). Positive associations were also found for hospitalization and FEV1 < 80%. High stress modified the relationship with unscheduled clinic/ED visits (high aOR = 7.7 95% CI 1.0, 60.2, versus normal aOR = 4.1 95% CI 0.8, 21.9). Path models identified direct and indirect effects (p = 0.05) indicating that a majority of the total effect on unscheduled clinic/ED visits is attributed directly to cockroach exposure. CONCLUSION: The strong association between cockroach exposure and asthma morbidity is not due to uncontrolled confounding by stress. The combination of cockroach exposure and high stress, common in urban homes, are modifiable factors associated with poor asthma outcomes.

Pyrethroid exposure among children residing in green versus non-green multi-family, low-income housing.

BACKGROUND: There is growing concern about children's chronic low-level pesticide exposure and its impact on health. Green building practices (e.g., reducing leakage of the thermal and pressure barrier that surrounds the structure, integrated pest management, improved ventilation) have the potential to reduce pesticide exposure. However, the potential impact of living in green housing on children's pesticide exposure is unknown. OBJECTIVE: To address this question, a longitudinal study of pyrethroid metabolites (3-phenoxybenzoic acid [3-PBA], 4-fluoro-3-phenoxybenzoic acid [4-F-3-PBA], trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid [trans-DCCA]) in first morning void urine, collected from 68 children from New Orleans, Louisiana residing in green and non-green housing was conducted. METHODS: Children were followed for 1 year with three repeated measures of pesticide exposure. Generalized estimating equations examined associations between housing type (green vs. non-green) and urinary pyrethroid metabolite concentrations adjusting for demographic and household factors over the year. RESULTS: Ninety-five percent of samples had detectable concentrations of 3-PBA (limit of detection [LOD]: 0.1 µg/L); 8% of 4-F-3-PBA (LOD: 0.1 µg/L), and 12% of trans-DCCA (LOD: 0.6 µg/L). In adjusted models, green housing was not associated with statistically significant differences in children's 3-PBA urinary concentrations compared to non-green housing.

The association between short-term residential black carbon concentration on blood pressure in a general population sample.

BACKGROUND: Exposure to black carbon indoors may be associated with blood pressure; however, evidence is limited to vulnerable subpopulations and highly exposed individuals. Our objective was to explore the relationship between indoor black carbon at various exposure windows on resting blood pressure in a general population sample. METHODS: Black carbon was measured in the home of 76 individuals aged 10-71 in New Orleans, Louisiana. Exposure was measured every 1 minute for up to 120 hours using an AE51 microaethalometer. Systolic blood pressure and diastolic blood pressure were measured at the conclusion of exposure monitoring. RESULTS: In adjusted models, at all exposure windows, increasing black carbon was associated with increased systolic blood pressure. The period 0-72 hours prior to blood pressure measurement showed the strongest effect; a 1 µg/m3 increase in black carbon was associated with a 7.55 mm Hg (P = .02) increase in systolic blood pressure. The relationship was stronger in participants reporting doctor-diagnosed hypertension (ß = 6.47 vs ß = 3.27). Black carbon was not associated with diastolic blood pressure. CONCLUSION: Increasing black carbon concentration indoors is positively associated with increasing systolic blood pressure with the most relevant exposure window being 0-72 hours prior to blood pressure measurement. Individuals with hypertension may be a more susceptible population.

Factors associated with using alternative sources of primary care: a cross-sectional study.

BACKGROUND: Mobile (MHCs), Community (CHCs), and School-based health clinics (SBHCs) are understudied alternative sources of health care delivery used to provide more accessible primary care to disenfranchised populations. However, providing access does not guarantee utilization. This study explored the utilization of these alternative sources of health care and assessed factors associated with residential segregation that may influence their utilization. METHODS: A cross-sectional study design assessed the associations between travel distance, perceived quality of care, satisfaction-adjusted distance (SAD) and patient utilization of alternative health care clinics. Adults (n = 165), child caregivers (n = 124), and adult caregivers (n = 7) residing in New Orleans, Louisiana between 2014 and 2015 were conveniently sampled. Data were obtained via face-to face interviews using standardized questionnaires and geospatial data geocoded using GIS mapping tools. Multivariate regression models were used to predict alternative care utilization. RESULTS: Overall 49.4% of respondents reported ever using a MCH, CHC, or SBHC. Travel distance was not significantly associated with using either MCH, CHC, or SBHC (OR = 0.91, 0.74-1.11 p > .05). Controlling for covariates, higher perceived quality of care (OR = 1.02, 1.01-1.04 p < .01) and lower SAD (OR = 0.81, 0.73-0.91 p < .01) were significantly associated with utilization. CONCLUSIONS: Provision of primary care via alternative health clinics may overcome some barriers to care but have yet to be fully integrated as regular sources of care. Perceived quality and mixed-methods measures are useful indicators of access to care. Future health delivery research is needed to understand the multiple mechanisms by which residential segregation influences health-seeking behavior.

Retinoblastoma in the United States: A 40-Year Incidence and Survival Analysis.

PURPOSE: To determine the incidence of retinoblastoma in the United States from 1973 to 2012 (40 years) and characterize the 5-year overall survival rate of the included patients. METHODS: Cases of retinoblastoma were derived from the Surveillance, Epidemiology, and End Results (SEER) Program (National Cancer Institute, Rockville, MD). Incidence rates were calculated using U.S. Census Bureau data as the standard population, and trends over time were determined using the chi-square test. Hazard ratios with a 95% confidence interval (CI) were estimated for variables associated with mortality using Cox regression models. Survival rates were calculated using the Kaplan-Meier method and compared among different clinical and demographic categories. RESULTS: A total of 879 cases of retinoblastoma were derived from the SEER databases. The annual incidence rates of retinoblastoma for a period of 40 years were 12.14 (95% CI: 11.32 to 12.96) cases per 1 million children 4 years or younger and 0.49 (95% CI: 0.36 to 0.65) cases per 1 million children between the ages of 5 and 9 years. There was no significant trend for children 4 years or younger (P = .6324) or between the ages of 5 and 9 years (P = .7695). The 5-year overall survival rates were 97.6%, 92.7%, 91.1%, and 96.4% for children diagnosed at the first, second, third, and after the third year of life, respectively (P = .0136). The 5-year overall survival rates were 92.5% for bilateral and 96.3% for unilateral cases (P = .0116). The 5-year overall survival rates were 90.8%, 92.5%, 97.6%, 97.3% for increasing time intervals (1973 to 1979, 1980 to 1989, 1990 to 1999, and 2000 to 2012, respectively; P = .0017). CONCLUSIONS: The incidence rate of retinoblastoma in the United States has remained stable for the past 40 years. Survival rate analysis indicates a significant effect of laterality of tumor, age at diagnosis, and decade of diagnosis. [J Pediatr Ophthalmol Strabismus. 2018;55(3):182-188.].

Housing conditions and birth outcomes: The National Child Development Study.

BACKGROUND: Despite their importance to respiratory and other health outcomes, housing conditions have been little-studied with respect to perinatal outcomes. METHODS: 1927 participants in the British National Child Development Study reported on housing conditions and pregnancy outcomes, including presence/severity of mold/dampness; type of heating; and whether remodeling of various sorts had been conducted. Crowding, based on the number of people in the residence and the number of rooms, was also considered. Outcomes assessed were low birthweight (< 2500g), preterm birth (< 37 weeks), and small-for-gestational-age (< 10th percentile for gestational age). Multiple logistic regression with adjustment for maternal, sociodemographic, and housing factors was conducted. RESULTS: Women who reported serious problems with mold were more likely to give birth to a low birthweight (adjusted OR 1.98, 95% CI 1.13-3.47) or small-for-gestational-age (2.06, 1.25-3.38) baby; no consistent associations were seen with preterm birth. Crowding was associated only with small-for-gestational-age (1.73, 1.11-2.76). CONCLUSIONS: Exposure to mold or dampness, and housing conditions generally, is a potentially important but under-investigated aspect of women's lives during pregnancy. Future studies should more thoroughly investigate housing characteristics and their relationship with birth outcomes.

The Distribution and Movement of American Cockroaches in Urban Niches of New Orleans.

American cockroaches are an important source of household allergens in tropical and semitropical climates. To determine which outdoor niches produce American cockroaches, traps were placed at 40 homes in New Orleans to collect nymphs. Nymphs were collected from the sewers, yards, and within the homes themselves. To compare sewers and yards as sources of cockroaches entering homes, adult cockroaches were collected, marked, and released into yards and sewers. No sewer-released cockroaches were collected in homes. Cockroaches released into yards were collected in the homes, suggesting that yards, rather than sewers, are a more important source niche. A field trial applying boric acid granules to the yard was performed in an effort to reduce entry of cockroaches. There was a significant reduction in the cockroach antigen collected in intervention homes compared with controls.

A single intervention for cockroach control reduces cockroach exposure and asthma morbidity in children.

BACKGROUND: Exposure to cockroaches is an important asthma trigger, particularly for children with asthma living in inner cities. Integrated pest management is the recommended approach to cockroach abatement; however, it is costly and difficult to implement. The impact of reducing cockroach exposure on asthma outcomes is not known. OBJECTIVE: We sought to test the use of a single intervention, insecticidal bait, to reduce cockroach exposure in the home of children with asthma in New Orleans and to examine the impact of cockroach reduction on asthma outcomes. METHODS: One hundred two children aged 5 to 17 years with moderate to severe asthma were enrolled in a 12-month randomized controlled trial testing the use of insecticidal bait on cockroach counts and asthma morbidity. Homes were visited 6 times and asthma symptoms were assessed every 2 months. RESULTS: After adjustment, intervention homes had significantly fewer cockroaches than did control homes (mean change in cockroaches trapped, 13.14; 95% CI, 6.88-19.39; P < .01). Children in control homes had more asthma symptoms and unscheduled health care utilization in the previous 2 weeks (1.82, 95% CI, 0.14-3.50, P = .03; 1.17, 95% CI, 0.11-2.24, P = .03, respectively) and a higher proportion of children with FEV1 of less than 80% predicted (odds ratio, 5.74; 95% CI, 1.60-20.57; P = .01) compared with children living in intervention homes. CONCLUSIONS: Previous research has demonstrated improvement in asthma health outcomes using multifaceted interventions. The strategic placement of insecticidal bait, which is inexpensive, has low toxicity, and is widely available, resulted in sustained cockroach elimination over 12 months and was associated with improved asthma outcomes. This single intervention may be an alternative to multifaceted interventions currently recommended to improve asthma morbidity.

Asthma severity, not asthma control, is worse in atopic compared with nonatopic adolescents with asthma.

BACKGROUND: The effects of atopic and nonatopic asthma phenotypes on asthma morbidity are unclear. Moreover, asthma morbidity in patients without atopy might be mediated by immunoglobulin E (IgE). OBJECTIVE: To determine differences in morbidity in patients with asthma with and without atopy in a population of inner-city adolescents with asthma and to assess the impact of total IgE (tIgE) in this population. METHODS: Data were obtained from 546 inner-city adolescents in the Asthma Control Evaluation study. A positive skin prick test reaction to 14 aeroallergens and specific IgE to 5 aeroallergens determined atopic status. High (≥75th percentile) and low (≤25th percentile) tIgE levels were categorized. Asthma control (Asthma Control Test) and asthma severity (Composite Asthma Severity Index [CASI]) were measured at multiple time points over 1 year. Fractional exhaled nitric oxide (FeNO) and measurements of morbidity also were collected. Multivariable and repeated measures analyses modeled the relation between atopic status and morbidity. RESULTS: Baseline CASI scores increased 0.90 point (P < .05) and FeNO increased 0.85 natural logarithmic unit (P < .001) in participants with vs without atopy. Repeated measures analyses showed consistent results. Participants without atopy and increased tIgE had FeNO 0.73 natural log unit higher (P < .01) than low tIgE and a nonsignificant increase in CASI. The CASI score and FeNO levels were higher for high than for low tIgE in participants with atopy. CONCLUSION: In this population, participants with atopic asthma had worse asthma severity and higher FeNO compared with those with nonatopic asthma, but no difference in control. In all participants, higher tIgE indicated worse severity and higher FeNO. In this population, asthma severity and FeNO might be mediated by IgE in the 2 asthma phenotypes.

Treatment outcomes and their determinants in HIV patients on Anti-retroviral Treatment Program in selected health facilities of Kembata and Hadiya zones, Southern Nations, Nationalities and Peoples Region, Ethiopia.

BACKGROUND: Ethiopia has been providing free Antiretroviral Treatment (ART) since 2005 for HIV/AIDS patients. ART improves survival time and quality of life of HIV patients but ART treatment outcomes might be affected by several factors. However, factors affecting treatment outcomes are poorly understood in Ethiopia. Hence, this study assesses treatment outcomes and its determinants for HIV patients on ART in selected health facilities of Kembata and Hadiya zones. METHODS: A retrospective cohort study was conducted on 730 adult HIV/AIDS patients who enrolled antiretroviral therapy from 2007 to 2011 in four selected health facilities of Kembata and Hadiya zones of Southern Ethiopia. Study subjects were sampled from the health facilities based on population proportion to size. Data was abstracted using data extraction format from medical records. Kaplan-Meier survival function was used to estimate survival probability. Cox proportional hazards regression model was used to identify factors associated with time to death. RESULT: Median age of patients was 32.4 years with Inter Quartile Range (IQR) [15, 65]. The female to male ratio of the study participants' was 1.4:1. Median CD4 count significantly increased during the last four consecutive years of follow up. A total of 92 (12.6%) patients died, 106(14.5%) were lost to follow-up, and 109(15%) were transferred out. Sixty three (68%) deaths occurred in the first 6 months of treatment. The median survival time was 25 months with IQR [9, 43]. After adjustment for confounders, WHO clinical stage IV [HR 2.42; 95% CI, 1.19, 5.86], baseline CD4 lymphocyte counts of 201 cell/mm(3) and 350 cell/mm(3) [HR 0.20; 95 % CI; 0.09-0.43], poor regimen adherence [HR 2.70 95% CI: 1.4096, 5.20], baseline hemoglobin level of 10 gm/dl and above [HR 0.23; 95% CI: 0.14, 0.37] and baseline functional status of bedridden [HR 3.40; 95% CI: 1.61, 7.21] were associated with five year survival of HIV patients on ART. CONCLUSION: All people living with HIV/AIDS should initiate ART as early as possible. Initiation of ART at the early stages of the disease, before deterioration of the functional status of the patients and before the reduction of CD4 counts and hemoglobin levels with an intensified health education on adherence to ART regimen is recommended.

Changes in low levels of lead over the course of pregnancy and the association with birth outcomes.

Data are lacking on the effect of low level prenatal lead exposure. We examined the change in blood lead from the second trimester until delivery and the association between maternal and cord blood lead and birth outcomes in 98 participants of the CANDLE birth cohort study. Mixed effects models were constructed to assess blood lead change over pregnancy and regression models were used to explore the relationship with cord blood lead, characteristics effecting maternal lead, birth weight and gestational age. Overall, the geometric mean maternal blood level was 0.43 µg/dL. Maternal blood lead at each time point was predictive of cord blood lead level. A 0.1 µg/dL increase in second trimester lead was associated with lower birth weight and pre-term birth. Maternal blood lead below 1 µg/dL behaves in a manner similar to lead at higher levels and is associated with a small decrease in birth weight and gestational age.

Impermeable dust mite covers in the primary and tertiary prevention of allergic disease: a meta-analysis.

BACKGROUND: Up to 40% of the world's population has been diagnosed with an allergic disease. The most prevalent allergy is to house dust mites. Impermeable mattress covers are often the first treatment in the prevention and decrease of symptoms of allergic disease. OBJECTIVE: To perform a meta-analysis evaluating the effectiveness of impermeable mattress covers in the primary prevention of allergic disease and as a single intervention in the tertiary prevention of allergic disease symptoms. METHODS: MEDLINE, Embase, Web of Science, and CINAHL were systematically searched for relevant publications. Seven primary prevention trials (n = 3,461) and 17 tertiary prevention trials (n = 1,671) met the inclusion criteria and were included in the review. All article reviews and abstractions were performed in duplicate. RESULTS: No significant pooled relative risks were found for the prevention of allergic disease. The pooled relative risks were 0.97 (95% confidence interval [CI] 0.62-1.51) for house dust mite sensitization, 0.92 (95% CI 0.81-1.05) for wheeze, 0.85 (95% CI 0.70-1.02) for asthma, 1.03 (95% CI 0.90-1.19) for allergic rhinitis, and 1.05 (95% CI 0.84-1.32) for allergic dermatitis. Likewise, no significant pooled standardized mean differences were found in the tertiary prevention of symptoms. The pooled standardized mean differences were -0.03 (95% CI -0.15 to 0.09) for peak flow, -0.06 (95% CI -0.32 to 0.20) for asthma symptom score, and -0.39 (95% CI -0.88 to 0.11) for nasal symptom score. A significant effect was seen in the decrease of house mite dust level in the mattress (-0.79, 95% CI -0.98 to -0.60). CONCLUSION: No evidence was found to support the use of impermeable mattress covers in the primary prevention of allergic disease or in the tertiary prevention of allergic disease symptoms.

The relationship between a specific IgE level and asthma outcomes: results from the 2005-2006 National Health and Nutrition Examination Survey.

BACKGROUND: Allergen exposure is associated with increased specific IgE (sIgE), and allergen exposure plus sensitization is predictive of asthma outcomes. However, it is not known if sIgE is predictive of asthma outcomes in the absence of exposure data. OBJECTIVE: To investigate whether IgE to indoor allergens is predictive of and has a dose-response relationship with asthma emergency department (ED) visits and wheeze. METHODS: In the 2005-2006 National Health and Nutrition Examination Survey, 351 children and 390 adults reported current asthma. Continuous sIgE to 9 indoor allergens were considered. Asthma morbidity in the past year was measured by wheezing. Health care utilization was defined as any asthma ED visits in the past year. RESULTS: Analyses were adjusted for race, age, education, poverty index ratio and (in adults) tobacco use. In children, ED visits were associated with cockroach (odds ratio [OR] 1.5 [95% CI, 1.1-2 .1), rat (OR 1.9 [95% CI, 1.2-2.8]), and Aspergillus (OR 1.6 [95% CI, 1.001-2.60]). Continuous Aspergillus (OR 1.5 [95% CI, 1.04-2.1), Alternaria (OR 1.4 [95% CI, 1.1-1.6]), and total IgE (OR 1.2 [95% CI, 1.1-1.4]) were associated with wheeze in children. Adult ED visits were associated with sIgE for dust mites (Dermatophagoides pteronyssinus OR 1.6 [95% CI, 1.3-2.1]; Dermatophagoides farinae OR 1.6 [95% CI, 1.3-1.9]), total IgE (OR 1.4 [95% CI, 1.04- 1.9]), and the sum of sIgEs (OR 1.6 [95% CI, 1.2-2.2]). CONCLUSIONS: Sensitization to particular indoor environmental allergens was found to be a risk factor for wheeze and asthma ED visits. These outcomes increased as the concentration of sIgE to these allergens increased.