Objective
To propose a comprehensive set of confounders and effect modifiers that should be considered in epidemiologic investigations.
Methods
Two reviewers independently critiqued studies included ...in a recent systematic review and extracted data on the confounders and effect modifiers that were considered and the approaches used to justify inclusion.
Results
Of the 62 studies reviewed, 20 were cohort, 16 case–control, 25 cross‐sectional studies, and one ecologic study. All cohort, cross‐sectional, and ecologic studies had some adjustment for confounding or consideration of effect modification, but this was only the case for 7/16 (44%) case–control studies. Of the 53 studies that considered confounding or effect modification, 39/53 (74%) gave no justification for the inclusion of the variables considered. Studies that justified the inclusion of the variables did so based on empirical evidence (n = 10), conceptual justification (n = 7), or a combination of the two (n = 3). Confounding was handled mainly by using regression modeling, but some case–control studies utilized matching and anova. Ten studies handled effect modification by stratification, eight tested for interaction, and five used both strategies.
Conclusions
We have found substantial shortcomings in the handling of confounding and effect modification in studies of diet and development of childhood asthma/allergies. Selection of variables should be based on conceptual considerations and empirical evidence. Using this approach, we have proposed a comprehensive set of confounders and effect modifiers that need to be considered in future studies.
Negative encounters with law enforcement-direct and vicarious-fuel mistrust. When considered as part of the 'risk environment' in public health and harm reduction research, law enforcement mistrust ...may have broad implications. For example, fearing arrest may prevent someone from calling 911 when witnessing an overdose or lead to syringe-sharing and community spread of HIV. For people in the US who identify as Black or African American, these effects may compound, given the ways in which communities of color have been overpoliced. The purpose of this study is to investigate the psychometrics of an adapted scale of law enforcement mistrust-the Group-Based Law Enforcement Mistrust Scale (GBLEMS)-and evaluate its associations with racial and ethnic identity and experiences with law enforcement.
This cross-sectional survey took place in a small city in the Western United States where only 3% of the population is Black or African American. The sample included Black or African American and Hispanic and Latina women at risk of HIV, and members of their social networks, yielding a diverse sample across racial, ethnic, and gender identities (N = 219). The GBLEMS is a 12-item scale adapted from the Group-Based Medical Mistrust Scale (GBMMS; Thompson et al. 2004). The current analysis evaluated the psychometric properties of the GBLEMS (reliability, exploratory factor analysis) and its associations with demographics, other race-based constructs, and experiences with law enforcement.
The GBLEMS demonstrated strong reliability (Cronbach's alpha = 0.92) and exploratory factor analysis indicated that items loaded onto two factors-mistrust and disparities in treatment. There was also support for the scale's construct validity. As hypothesized, GBLEMS scores were higher among respondents who identify as Black or African American, and among those who reported other experiences of racial discrimination, medical mistrust, and negative encounters with law enforcement.
This study yielded support for the reliability and validity of the GBLEMS as a multi-item, two-factor scale measuring group-based law enforcement mistrust. When framing public health and harm reduction research in terms of the risk environment, law enforcement mistrust may be important to measure as part of a comprehensive approach that addresses persistent racial disparities.
Background: Associations between maternal vitamin E, vitamin D and zinc intakes during pregnancy and asthma, wheeze and eczema in 5-year-old children have previously been reported. A study was ...undertaken to investigate whether maternal intake of specific foods during pregnancy is associated with asthma and allergic outcomes in the same children. Methods: A longitudinal birth cohort study was conducted in 1924 children born to women recruited during pregnancy. Maternal diet during pregnancy was assessed by food frequency questionnaire (FFQ). Cohort children were followed up at 5 years by symptom questionnaire and FFQ. Food groups of interest were fruit, vegetables, fruit juice, whole grain products, fish, dairy products and fat spreads. Trends across outcome groups defined by level of food intake are presented. Results: 1253 children participated at 5 years and maternal FFQ data were available for 1212. No consistent associations were found between childhood outcomes and maternal intake of the analysed foods except for apples and fish. Maternal apple intake was beneficially associated with ever wheeze (OR highest vs lowest tertile 0.63, 95% CI 0.42 to 0.95), ever asthma (OR 0.54, 95% CI 0.32 to 0.92) and doctor-confirmed asthma (OR 0.47, 95% CI 0.27 to 0.82) in the children. Maternal fish consumption was beneficially associated with doctor-confirmed eczema (OR ⩾1/week vs never 0.57, 95% CI 0.35 to 0.92). Conclusion: There was no evidence for associations between maternal intake of most foods during pregnancy and asthma, respiratory and allergic outcomes in 5-year-old children, except for apples and fish. Consumption of apples and fish during pregnancy may have a protective effect against the development of childhood asthma and allergic disease.
Injury to the airway epithelium has been proposed as a key susceptibility factor for exercise-induced bronchoconstriction (EIB). Our goals were to establish whether airway epithelial cell injury ...occurs during EIB in athletes and whether inhalation of warm humid air inhibits this injury. Twenty-one young male athletes (10 with a history of EIB) performed two 8-min exercise tests near maximal aerobic capacity in cold dry (4°C, 37% relative humidity) and warm humid (25°C, 94% relative humidity) air on separate days. Postexercise changes in urinary CC16 were used as a biomarker of airway epithelial cell perturbation and injury. Bronchoconstriction occurred in eight athletes in the cold dry environment and was completely blocked by inhalation of warm humid air maximal fall in forced expiratory volume in 1 s = 18.1 ± 2.1% (SD) in cold dry air and 1.7 ± 0.8% in warm humid air, P < 0.01. Exercise caused an increase in urinary excretion of CC16 in all subjects (P < 0.001), but this rise in CC16 was blunted following inhalation of warm humid air median CC16 increase pre- to postchallenge = 1.91 and 0.35 ng/μmol in cold dry and warm humid air, respectively, in athletes with EIB (P = 0.017) and 1.68 and 0.48 ng/μmol in cold dry and warm humid air, respectively, in athletes without EIB (P = 0.002). The results indicate that exercise hyperpnea transiently disrupts the airway epithelium of all athletes (not only in those with EIB) and that inhalation of warm moist air limits airway epithelial cell perturbation and injury.
Carbon monoxide (CO) is a poisonous gas produced by incomplete combustion of carbon-based fuels that is linked to mortality and morbidity. Household air pollution from burning fuels on poorly ...ventilated stoves can lead to high concentrations of CO in homes. There are few datasets available on household concentrations of CO in urban areas of sub-Saharan African countries. CO was measured every minute over 24 h in a sample of homes in Nairobi, Kenya. Data on household characteristics were gathered by questionnaire. Metrics of exposure were summarised and analysis of temporal changes in concentration was performed. Continuous 24-h data were available from 138 homes. The mean (SD), median (IQR) and maximum 24-h CO concentration was 4.9 (6.4), 2.8 (1.0–6.3) and 44 ppm, respectively. 50% of homes had detectable CO concentrations for 847 min (14h07m) or longer during the 24-h period, and 9% of homes would have activated a CO-alarm operating to European specifications. An association between a metric of total CO exposure and self-reported exposure to vapours >15 h per week was identified, however this were not statistically significant after adjustment for the multiple comparisons performed. Mean concentrations were broadly similar in homes from a more affluent area and an informal settlement. A model of typical exposure suggests that cooking is likely to be responsible for approximately 60% of the CO exposure of Nairobi schoolchildren. Household CO concentrations are substantial in Nairobi, Kenya, despite most homes using gas or liquid fuels. Concentrations tend to be highest during the evening, probably associated with periods of cooking. Household air pollution from cooking is the main source of CO exposure of Nairobi schoolchildren. The public health impacts of long-term CO exposure in cities in sub-Saharan Africa may be considerable and should be studied further.
Display omitted
•Carbon monoxide concentrations in homes in a large African city are substantial.•Exposure to CO is likely to adversely affect the health of many urban dwellers in Africa.•CO levels were similar in homes in an informal settlement and a more affluent area.•Children receive most of their CO exposure during the evening when dinner is prepared.
Courtrooms are often emotionally charged atmospheres where parties have a vested interest in the proceedings and their outcomes. Judges are exposed to a wide range of emotions and stressors in the ...course of their work. Though the ideal of a dispassionate judge persists, more empirical work is needed to identify how judges regulate their own emotional experience in court. Using Maroney and Gross typology of emotion regulation strategies, this study explored the self-reported use and preference of these strategies among a sample of U.S. judges. Using both quantitative and qualitative approaches, we found that judges reported using a variety of intrinsic (self-directed) and extrinsic (directed toward others) emotion regulation strategies, though judges reported using some strategies such as suppression more frequently than others. We also found that many of the strategies judges described matched a subset of the strategies described by Maroney and Gross supporting their typology.
Summary
Background
It has been hypothesized that changes in diet during early life may have contributed to the increase in childhood asthma and atopy. The long‐term effect of the timing and content ...of infant feeding on the incidence of asthma and atopic diseases in children is unclear.
Objective
To investigate the associations between duration of breastfeeding and the timing of introduction of complementary foods during the first 6 months and parental‐reported asthma, wheeze and atopic eczema up to 10 years of age.
Methods
Infant feeding practices (breastfeeding and introduction of complementary foods) of 1924 singleton children participating in the Study of Eczema and Asthma To Observe the influence of Nutrition (SEATON) birth cohort were prospectively collected up to 6 months with outcomes (wheeze, atopic eczema and asthma) being assessed at 1, 2, 5 and 10 years. Data were analysed using generalized estimating equations and discrete hazards models with adjustment for confounders.
Results
By 6 months, 59% and 35% of mothers had stopped exclusive and total breastfeeding, respectively. Although formula feeding was adversely associated with wheeze in the past 12 months (adjusted OR for no formula feeding: 070, 95% CI 0.50–0.97), and the introduction of biscuits/bread after 5 months of age adversely associated with atopic eczema (adjusted OR 1.34, 95% CI 1.06–1.69), these results lost their statistical significance after adjustment for multiple testing. Stratification of the results by the presence of eczema by 6 months of age and family atopic history did not substantially differ from the results of the whole study population.
Conclusion and Clinical Relevance
Our results suggest that the nature of infant feeding during the first 6 months seems not to substantially influence the long‐term risk of asthma and atopic diseases in children, nor in children at high risk of atopic disease because of a family history of atopic disease.
Background The environmental factors responsible for recent increases in the prevalence of asthma and atopic disease have been assumed to act after birth. Their possible effects on fetal immune ...development in utero have not been investigated systematically, although sensitization to allergens may occur before birth.
Objective This prospective study determined whether the risk factors for asthma and atopic disease, namely family history of atopic disease, maternal smoking, birth order, or maternal dietary intake of antioxidant vitamins, exert antenatal effects on the fetal immune system that may predispose to childhood atopy.
Methods The T helper (Th) cell proliferative responses of cord blood mononuclear cells (CBMC) from a sample of 223 neonates, representative of children born to a cohort of 2000 pregnant women, were measured and related to family, maternal and environmental factors associated with the pregnancy.
Results The magnitude of CBMC‐proliferative responses to allergens increased significantly in association with a family history of atopic disease or maternal smoking, and decreased significantly with increasing birth order and high maternal dietary intake of vitamin E. The epidemiological association between birth order and atopy may therefore be a consequence of antenatal influences rather than of protective effects of childhood infections. The association between maternal intake of vitamin E and CBMC responsiveness suggests that diet during pregnancy may influence the fetal immune system in such a way as to modulate the risk of childhood atopy.
Conclusion These results provide a new insight into the aetiology of atopic disease by demonstrating that the maternal environmental risk factors for atopy, diet, birth order and smoking, influence the development of the fetal immune system. This raises the prospect of preventative public health interventions during pregnancy.
Summary
Speculation persists as to the possible role, if any, of dietary antioxidants in allergic disease. While it has been hypothesized that the recent increase in allergic disease is a consequence ...of declining dietary antioxidant intake, an alternative hypothesis proposes that the increase in allergic disease is due to increasing antioxidant intake. Dietary trends are conflicting; the intake of some antioxidants has declined, for others intakes are likely to have increased. Animal model studies demonstrate that antioxidant supplementation at the time of primary and subsequent allergen exposure attenuates allergic inflammatory responses. The data from human studies are less clear. Observational epidemiological studies of humans are beset by several methodological limitations associated with the assessment of diet and predominantly focus on asthma. Most observational studies report potentially beneficial associations between dietary antioxidants and allergic outcomes, but a small minority report potentially adverse associations. Human intervention studies suggest that single antioxidant supplements confer minimal, if any clinical benefit in adults with asthma, however, there is still scope for studies in children, atopic dermatitis, allergic rhinitis (AR) and of antioxidant combinations. More recently, it has been suggested that dietary antioxidants in the developmental context of fetal and infant development influence the development childhood asthma and atopic sensitization possibly by affecting the first interactions between the neonatal immune system and allergens. While a small number of birth cohort studies have reported potentially beneficial associations between maternal intake of some antioxidants during pregnancy and childhood asthma, there is very limited data suggesting associations between maternal antioxidant intake and childhood atopic dermatitis and AR. The available epidemiological, animal, molecular and immunological data suggest that there are associations between antioxidants and asthma and to a much lesser extent, atopic dermatitis and AR. However, the exact nature of the relationships and the potential for therapeutic intervention remain unclear.
Cite this as: K. Allan, F. J. Kelly and G. Devereux, Clinical & Experimental Allergy, 2010 (40) 370–380.
BACKGROUND: The greatest burden of chronic respiratory disease is in low- and middle-income countries, with recent population-based studies reporting substantial levels of obstructive and restrictive ...lung function.OBJECTIVE: To characterise the common chronic respiratory
diseases encountered in hospital outpatient clinics in three African countries.METHODS This was a cross-sectional study of consecutive adult patients with chronic respiratory symptoms (>8 weeks) attending hospital outpatient departments in Ethiopia, Kenya and Sudan. Patients
were assessed using a respiratory questionnaire, spirometry and chest radiography. The diagnoses of the reviewing clinicians were ascertained.RESULT: A total of 519 patients (209 Kenya, 170 Ethiopia, 140 Sudan) participated; the mean age was 45.2 years (SD 16.2); 53% were women,
83% had never smoked. Reviewing clinicians considered that 36% (95% CI 32-40) of patients had asthma, 25% (95% CI 21-29) had chronic bronchitis, 8% (95% CI 6-11) chronic obstructive pulmonary disease (COPD), 5% (95% CI 4-8) bronchiectasis and 4% (95% CI 3-6) post-TB
lung disease. Spirometry consistent with COPD was present in 35% (95% CI 30-39). Restriction was evident in 38% (95% CI 33-43). There was evidence of sub-optimal diagnosis of asthma and COPD.CONCLUSION: In Ethiopia, Kenya and Sudan, asthma, COPD and chronic bronchitis
account for the majority of diagnoses in non-TB patients with chronic respiratory symptoms. The suboptimal diagnosis of these conditions will require the widespread use of spirometry.
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