Objective

African Americans are disproportionately burdened by asthma. We assessed the individual and joint contribution of socioeconomic status (SES) on asthma morbidity among African American youth.

Methods

We examined 686 African Americans (8-21 years) with asthma. To account for the joint effects of SES, a composite index was derived from maternal educational attainment, household income, and insurance status. Ordinal logistic regression was used to estimate the individual and joint effect of SES on asthma control. Models were adjusted for age, sex, controller medication use, in utero smoke exposure, family history of asthma, family history of rhinitis, breastfeeding, daycare attendance, and mold exposure.

Results

Participants were classified as Poorly Controlled Asthma (40.8%), Partially Controlled Asthma (29.7%), or Controlled Asthma (30.2%). Of the individual SES indicators, low income was the strongest predictor of poor asthma control. Children with low income had worse asthma control than those with higher income (OR 1.39; 95% CI 0.92-2.12). The SES index ranged from 4-9. SES was associated with 17% increased odds of poor asthma control with each decrease in the index (95% CI 1.05-1.32). The SES index was associated with asthma-related symptoms, nocturnal awakenings, limited activity, and missed school days.

Conclusions

The negative effects of SES were observed along the entire socioeconomic gradient, and the adverse asthma outcomes observed in African American youth were not limited to the very poor. We also found that the SES index may be a more consistent and useful predictor of poor asthma outcomes than each indicator alone.

Rationale

Air pollution is a known asthma trigger and has been associated with short-term asthma symptoms, airway inflammation, decreased lung function, and reduced response to asthma rescue medications.

Objectives

To assess a causal relationship between air pollution and childhood asthma using data that address temporality by estimating air pollution exposures before the development of asthma and to establish the generalizability of the association by studying diverse racial/ethnic populations in different geographic regions.

Methods

This study included Latino (n = 3,343) and African American (n = 977) participants with and without asthma from five urban regions in the mainland United States and Puerto Rico. Residential history and data from local ambient air monitoring stations were used to estimate average annual exposure to five air pollutants: ozone, nitrogen dioxide (NO₂), sulfur dioxide, particulate matter not greater than 10 μm in diameter, and particulate matter not greater than 2.5 μm in diameter. Within each region, we performed logistic regression to determine the relationship between early-life exposure to air pollutants and subsequent asthma diagnosis. A random-effects model was used to combine the region-specific effects and generate summary odds ratios for each pollutant.

Measurements and main results

After adjustment for confounders, a 5-ppb increase in average NO₂ during the first year of life was associated with an odds ratio of 1.17 for physician-diagnosed asthma (95% confidence interval, 1.04-1.31).

Conclusions

Early-life NO₂ exposure is associated with childhood asthma in Latinos and African Americans. These results add to a growing body of evidence that traffic-related pollutants may be causally related to childhood asthma.

Rationale

Obesity is associated with increased asthma morbidity, lower drug responsiveness to inhaled corticosteroids, and worse asthma control. However, most prior investigations on obesity and asthma control have not focused on pediatric populations, considered environmental exposures, or included minority children.

Objectives

To examine the association between body mass index categories and asthma control among boys and girls; and whether these associations are modified by age and race/ethnicity.

Methods

Children and adolescents ages 8-19 years (n = 2,174) with asthma were recruited from the Genes-environments and Admixture in Latino Americans (GALA II) Study and the Study of African Americans, Asthma, Genes, and Environments (SAGE II). Ordinal logistic regression was used to estimate odds ratios (OR) and their confidence intervals (95% CI) for worse asthma control.

Measurements and main results

In adjusted analyses, boys who were obese had a 33% greater chance of having worse asthma control than their normal-weight counterparts (OR, 1.33; 95% CI, 1.04-1.71). However, for girls this association varied with race and ethnicity (P interaction = 0.008). When compared with their normal-weight counterparts, obese African American girls (OR, 0.65; 95% CI, 0.41-1.05) were more likely to have better controlled asthma, whereas Mexican American girls had a 1.91 (95% CI, 1.12-3.28) greater odds of worse asthma control.

Conclusions

Worse asthma control is uniformly associated with increased body mass index in boys. Among girls, the direction of this association varied with race/ethnicity.

American Thoracic Society guidelines recommend inhaled corticosteroid (ICS) therapy, plus a short-acting bronchodilator, in patients with persistent asthma. However, few prior studies have examined the efficacy of this combination in children of all racial/ethnic groups. We evaluated the association between ICS use and bronchodilator response (BDR) in three pediatric populations with persistent asthma (656 African American, 916 Puerto Rican, and 398 Mexican American children). The association was assessed using multivariable quantile regression. After adjusting for baseline forced expiratory volume in one second and use of controller medications, ICS use was significantly associated with increased BDR only among Mexican Americans (1.56%, P = 0.028) but not African Americans (0.49%, P = 0.426) or Puerto Ricans (0.16%, P = 0.813). Our results demonstrate that ICS augmentation is disproportionate across racial/ethnic groups, where improved BDR is observed in Mexican Americans only. This study highlights the complexities of treating asthma in children, and reinforces the importance of investigating the influence of race/ethnicity on pharmacological response.

Background

Asthma disproportionately affects minority populations and is associated with psychosocial stress such as racial/ethnic discrimination. We aimed to examine the association of perceived discrimination with asthma and poor asthma control in African American and Latino youth.

Methods

We included African American (n = 954), Mexican American (n = 1,086), other Latino (n = 522), and Puerto Rican Islander (n = 1,025) youth aged 8 to 21 years from the Genes-Environments and Admixture in Latino Americans study and the Study of African Americans, Asthma, Genes, and Environments. Asthma was defined by physician diagnosis, and asthma control was defined based on the National Heart, Lung, and Blood Institute guidelines. Perceived racial/ethnic discrimination was assessed by the Experiences of Discrimination questionnaire, with a focus on school, medical, and public settings. We examined the associations of perceived discrimination with each outcome and whether socioeconomic status (SES) and global African ancestry modified these associations.

Results

African American children reporting any discrimination had a 78% greater odds of experiencing asthma (OR, 1.78; 95% CI, 1.33-2.39) than did those not reporting discrimination. Similarly, African American children faced increased odds of poor asthma control with any experience of discrimination (OR, 1.97; 95% CI, 1.42-2.76) over their counterparts not reporting discrimination. These associations were not observed among Latino children. We observed heterogeneity of the association between reports of discrimination and asthma according to SES, with reports of discrimination increasing the odds of having asthma among low-SES Mexican American youth (interaction P = .01) and among high-SES other Latino youth (interaction P = .04).

Conclusions

Perceived discrimination is associated with increased odds of asthma and poorer control among African American youth. SES exacerbates the effect of perceived discrimination on having asthma among Mexican American and other Latino youth.

A BAFF polymorphism is associated with asthma exacerbations and serum BAFF levels. BAFF expression in vivo increases in natural rhinovirus infection. BAFF may play a role in airway antiviral immunity and impact asthma exacerbation rates.

Background

Obesity is associated with poor asthma control, increased asthma morbidity, and decreased response to inhaled corticosteroids. We hypothesized that obesity would be associated with decreased bronchodilator responsiveness in children and adolescents with asthma. In addition, we hypothesized that subjects who were obese and unresponsive to bronchodilator would have worse asthma control and would require more asthma controller medications.

Methods

In the Study of African Americans, Asthma, Genes, and Environments (SAGE II) and the Genes-environments and Admixture in Latino Americans (GALA II) study, two identical, parallel, case-control studies of asthma, we examined the association between obesity and bronchodilator response in 2,963 black and Latino subjects enrolled from 2008 to 2013 using multivariable logistic regression. Using bronchodilator responsiveness, we compared asthma symptoms, controller medication usage, and asthma exacerbations between nonobese (< 95th% BMI) and obese (≥ 95th% BMI) subjects.

Results

The odds of being bronchodilator unresponsive were 24% (OR, 1.24; 95% CI, 1.03-1.49) higher among obese children and adolescents compared with their not obese counterparts after adjustment for age, race/ethnicity, sex, recruitment site, baseline lung function (FEV1/FVC), and controller medication. Bronchodilator-unresponsive obese subjects were more likely to report wheezing (OR, 1.38; 95% CI, 1.13-1.70), being awakened at night (OR, 1.34; 95% CI, 1.09-1.65), using leukotriene receptor inhibitors (OR, 1.33; 95% CI, 1.05-1.70), and using inhaled corticosteroid with long-acting β2-agonist (OR, 1.37; 95% CI, 1.05-1.78) than were their nonobese counterpart. These associations were not seen in the bronchodilator-responsive group.

Conclusions

Obesity is associated with bronchodilator unresponsiveness among black and Latino children and adolescents with asthma. The findings on obesity and bronchodilator unresponsiveness represent a unique opportunity to identify factors affecting asthma control in blacks and Latinos.

Rationale

The burden of asthma is highest among socioeconomically disadvantaged populations; however, its impact is differentially distributed among racial and ethnic groups.

Objectives

To assess the collective effect of maternal educational attainment, annual household income, and insurance type on childhood asthma among minority, urban youth.

Methods

We included Mexican American (n = 485), other Latino (n = 217), and African American (n = 1,141) children (aged 8-21 yr) with and without asthma from the San Francisco Bay Area. An index was derived from maternal educational attainment, annual household income, and insurance type to assess the collective effect of socioeconomic status on predicting asthma. Logistic regression stratified by racial and ethnic group was used to estimate adjusted odds ratios (aOR) and their 95% confidence intervals (CI). We further examined whether acculturation explained the socioeconomic-asthma association in our Latino population.

Measurements and main results

In the adjusted analyses, African American children had 23% greater odds of asthma with each decrease in the socioeconomic index (aOR, 1.23; 95% CI, 1.09-1.38). Conversely, Mexican American children have 17% reduced odds of asthma with each decrease in the socioeconomic index (aOR, 0.83; 95% CI, 0.72-0.96) and this relationship was not fully explained by acculturation. This association was not observed in the other Latino group.

Conclusions

Socioeconomic status plays an important role in predicting asthma, but has different effects depending on race and ethnicity. Further steps are necessary to better understand the risk factors through which socioeconomic status could operate in these populations to prevent asthma.

Rationale

Severe early-life respiratory illnesses, particularly those caused by respiratory syncytial virus (RSV) and human rhinovirus (HRV), are strongly associated with the development of asthma in children. Puerto Rican children in particular have a strikingly high asthma burden. However, prior studies of the potential associations between early-life respiratory illnesses and asthma in Puerto Rican and other minority populations have been limited.

Objectives

We sought to determine whether early-life respiratory illness was associated with asthma in Puerto Rican, Mexican American, and African American children.

Methods

Using a logistic regression analysis, we examined the association between early-life respiratory illnesses (report of upper respiratory infection (URI), pneumonia, bronchitis, and bronchiolitis/RSV) within the first two years of life and physician-diagnosed asthma after the age of two in a large cohort of Puerto Rican, Mexican American, and African American children.

Measurements and main results

While early-life respiratory illnesses were associated with greater asthma odds in Puerto Ricans, Mexican Americans, and African Americans, these associations were stronger among Puerto Rican children. Specifically, in Puerto Ricans, the odds was 6.15 (95% CI: 4.21-9.05) if the child reported at least one of the following respiratory illness: URI, pneumonia, bronchitis or bronchiolitis. The odds were also higher in Puerto Ricans when considering these conditions separately.

Conclusions

We observed population-specific associations between early-life respiratory illnesses and asthma, which were especially significant and stronger in Puerto Ricans. Taken together with the known high burden of RSV in Puerto Rico, our results may help explain the high burden of asthma in Puerto Ricans.

American Thoracic Society guidelines recommend inhaled corticosteroid (ICS) therapy, plus a short-acting bronchodilator, in patients with persistent asthma. However, few prior studies have examined the efficacy of this combination in children of all racial/ethnic groups. We evaluated the association between ICS use and bronchodilator response (BDR) in three pediatric populations with persistent asthma (656 African American, 916 Puerto Rican, and 398 Mexican American children). The association was assessed using multivariable quantile regression. After adjusting for baseline forced expiratory volume in one second and use of controller medications, ICS use was significantly associated with increased BDR only among Mexican Americans (1.56%, P = 0.028) but not African Americans (0.49%, P = 0.426) or Puerto Ricans (0.16%, P = 0.813). Our results demonstrate that ICS augmentation is disproportionate across racial/ethnic groups, where improved BDR is observed in Mexican Americans only. This study highlights the complexities of treating asthma in children, and reinforces the importance of investigating the influence of race/ethnicity on pharmacological response.