Exposure to violence and asthma in Puerto Rican youth with high Th2 immunity.

BACKGROUND: Little is known about the determinants of asthma among youth with high T helper 2 (Th2) immunity. We hypothesized that exposure to violence (ETV) and violence-related distress are associated with asthma in children and adolescents with high Th2 immunity. METHODS: We analyzed data from Puerto Ricans with high Th2 immunity aged 9-20 years in the Puerto Rico Genetics of Asthma and Lifestyle (PR-GOAL) and the Epigenetic Variation of Childhood Asthma in Puerto Ricans (EVA-PR) studies, and in a prospective study (PROPRA). High Th2-immunity was defined as ≥1 positive allergen-specific IgE and/or a total IgE ≥ 100 IU/mL and/or an eosinophil count ≥ 150 cells/µL. Asthma was defined as physician-diagnosed asthma and current wheeze. ETV and violence-related distress were assessed with the validated ETV Scale and Checklist of Children's Distress Symptoms (CCDS) questionnaires, respectively. RESULTS: In multivariable analyses, each 1-point increment in ETV score was significantly associated with 1.13-1.17 times increased odds of asthma in PR-GOAL and in EVA-PR (both at p ≤ 0.01), and each 1-point increment in CCDS score was significantly associated with 1.53-1.54 increased odds of asthma in PR-GOAL and in EVA-PR (both at p ≤ 0.03). Further, a persistently high ETV score was significantly associated with asthma in PROPRA (odds ratio [OR] = 2.83, 95% confidence interval [CI] = 1.10-7.29). Similar results were obtained in a sensitivity analysis using an eosinophil count ≥ 300 cells/µL instead of ≥150 cells/µL to define high Th2 immunity. CONCLUSIONS: ETV during childhood is associated with increased risk of persistent or new-onset asthma in youth with high Th2 immunity.

Diet, Asthma, and Severe Asthma Exacerbations in a Prospective Study of Puerto Rican Youth.

BACKGROUND: Poor diet quality may contribute to the disproportionate asthma burden in Puerto Rican youth. OBJECTIVE: To examine whether an unhealthy diet at one or two study visits conducted over about 5 years was associated with asthma, severe asthma exacerbations, and worse lung function in Puerto Rican youth. METHODS: This was a prospective study of 406 Puerto Rican youth aged 6 to 14 years at a baseline visit and 9 to 20 years at a follow-up visit. As in prior work, diet was assessed using a dietary score ranging from -2 to +2. The exposure of interest was an unhealthy diet, defined as a nonpositive dietary score (0 to -2) at one or both visits. Outcomes of interest were asthma (defined as physician-diagnosed asthma and one of more episode of wheeze in the year before the second visit), one or more severe asthma exacerbation in the year before the second visit, and change in percent predicted lung function measures (FEV1, FVC, and FEV1/FVC) between the first and second visits. RESULTS: In a multivariable analysis, an unhealthy diet at both visits was associated with increased odds of asthma (adjusted odds ratio = 3.38; 95% confidence interval, 1.74-6.57) and severe asthma exacerbations (adjusted odds ratio = 2.65; 95% confidence interval, 1.16-6.03), but not with change in lung function. CONCLUSIONS: An unhealthy diet at both visits was associated with increased odds of asthma and severe asthma exacerbations, compared with a healthy diet at both visits. Our findings support health policies promoting a healthy diet in Puerto Rican youth, a population at high risk for asthma.

Effect of vitamin D supplementation on total and allergen-specific IgE in children with asthma and low vitamin D levels.

BACKGROUND: Observational studies have yielded inconsistent findings for the relation between vitamin D level and total IgE or allergic sensitization. OBJECTIVE: To determine whether vitamin D supplementation reduces levels of total IgE and IgE to each of 2 common indoor allergens in children with asthma and low vitamin D levels. METHODS: Total IgE, IgE to Dermatophagoides pteronyssinus, and IgE to Blattella germanica were measured at the randomization and exit visits for 174 participants in the Vitamin D Kids Asthma Study, a multicenter, double-blind, randomized placebo-controlled trial of vitamin D3 supplementation (4000 IU/d) to prevent severe exacerbations in children with persistent asthma and vitamin D levels less than 30 ng/mL. Multivariable linear regression was used for the analysis of the effect of vitamin D supplementation on change in each IgE measure. RESULTS: Participants were followed for an average of 316 days. At the exit visit, more subjects in the vitamin D arm achieved a vitamin D level equal to or more than 30 ng/mL compared with those in the placebo arm (87% vs 30%; P < .001). In a multivariable analysis, vitamin D3 supplementation had no significant effect on change in total IgE, IgE to Dermatophagoides pteronyssinus, or IgE to Blattella germanica between the exit and randomization visits (eg, for log10 total IgE, ß = 0.007; 95% CI, -0.061 to 0.074; P = .85). CONCLUSIONS: Vitamin D supplementation, compared with placebo, has no significant effect on serum levels of total IgE, IgE to dust mite, or IgE to cockroach in children with asthma and low vitamin D levels.

Maternal Depressive Symptoms, Lung Function, and Severe Asthma Exacerbations in Puerto Rican Children.

BACKGROUND: Maternal depression has been linked to health care use for asthma in cross-sectional or short-term follow-up studies of school-aged children. OBJECTIVE: To examine whether increased or persistent maternal depressive symptoms over approximately 5 years are associated with severe asthma exacerbations or worse lung function in youth. METHODS: A prospective study of 386 youth living in Puerto Rico, aged 6 to 14 years at a baseline visit and 9 to 20 years at a second visit, was performed. Our exposure of interest was change in persistence of maternal depressive symptoms, assessed at both visits using the Center for Epidemiologic Studies Depression Scale (CESD). Our outcomes of interest were change in percent predicted forced expiratory volume in 1 second (FEV1) and FEV1/forced vital capacity (FVC) between the first and second visits in all subjects, and ≥1 severe asthma exacerbation in the year before the second visit in subjects with asthma. RESULTS: In a multivariable analysis, each 1-point increment in the CESD score was associated with decrements of 0.15% in percent predicted FEV1 (95% confidence interval [CI] = -0.28% to -0.01%; P = .03) and 0.10% in percent predicted FEV1/FVC (95% CI = -0.20% to 0.001%; P = .05) between visits, as well as with 1.03 times increased odds of ≥1 severe asthma exacerbation at the second visit (95% CI for odds ratio = 0.99 to 1.06, P = .09). In a multivariable analysis, the presence of maternal depressive symptoms (a CESD score ≥21 points) at the second visit or at both visits was significantly associated with 3.17 to 3.52 times increased odds of ≥1 severe asthma exacerbation in the year before the second visit. CONCLUSIONS: Increasing or persistent maternal depressive symptoms over approximately 5 years are associated with worse lung function measures and severe asthma exacerbations among Puerto Rican youth, a high-risk population.

Indoor endotoxin, proximity to a major roadway, and severe asthma exacerbations among children in Puerto Rico.

BACKGROUND: Few studies have examined concurrent exposure to household endotoxin and traffic-related air pollution in relation to childhood asthma, yet both factors are associated with asthma outcomes. OBJECTIVE: To examine whether proximity to a major roadway (a traffic-related air pollution proxy) modifies the estimated effects of indoor endotoxin on asthma outcomes in children. METHODS: Cross-sectional study of 200 children with asthma (ages, 6-14 years) living in Puerto Rico. Residential distance to a major roadway was calculated as the distance from the participant's residential US census block centroid to the nearest major road. The outcomes of interest were severe asthma exacerbations, missed school days for asthma, atopy, lung function, and bronchodilator response (BDR). Logistic, linear, or negative binomial regression was used for the multivariable analysis. RESULTS: In the multivariable analysis, there was an interaction between indoor endotoxin and residential distance to a roadway on severe asthma exacerbations (P = .02) and BDR (P = .07). In an analysis stratified by distance to a roadway, each log10-unit increase in endotoxin was associated with 4.21 times increased odds of severe asthma exacerbations among children living within 499 m (the lower 3 quartiles of residential distance) to a road (95% confidence interval, 1.5-12.0). Among subjects living further than 499 m away from a roadway, each log10-unit increase in endotoxin was associated with reduced odds of severe asthma exacerbations (odds ratio, 0.03; 95% confidence interval, 0.001-0.67). Similar but less substantial findings were observed for BDR. CONCLUSION: Our findings suggest that residential proximity to a major road modifies the estimated effect of endotoxin on severe asthma exacerbations in children.

Risk factors for atopic and nonatopic asthma in Puerto Rican children.

BACKGROUND: Little is known about the risk factors for atopic and nonatopic asthma among children in Puerto Rico. We aimed to identify modifiable risk factors for atopic and nonatopic asthma in this vulnerable population. METHODS: Case-control study of children with (n = 305) and without (n = 327) asthma in San Juan (Puerto Rico). Asthma was defined as physician-diagnosed asthma and wheeze in the previous year. Atopic asthma (n = 210) was defined as asthma and greater than or equal to one positive IgE to aero-allergens. Nonatopic asthma (n = 95) was defined as asthma and no positive IgE to the allergens tested. Logistic regression was used for the multivariable analysis of atopic and nonatopic asthma. RESULTS: In a multivariable analysis, body mass index (BMI) z score, prematurity, parental asthma, lifetime exposure to gun violence, and having a bird in the child's home were associated with increased odds of atopic asthma, while each one-point increment in a dietary score (range: -2 [least healthy diet] to +2 [healthiest diet]) was associated with 37% reduced odds of atopic asthma (95% confidence interval [CI] = 0.48-0.81; P < .01). In a separate multivariable analysis, parental asthma, early-life second-hand smoke (SHS) exposure, and daycare attendance in the first year of life were significantly associated with increased odds of nonatopic asthma, while each one-point increment in the dietary score was associated with 42% reduced odds of nonatopic asthma (95% CI = 0.45-0.76; P < .01). CONCLUSIONS: We have identified potentially modifiable risk factors for atopic asthma (eg, BMI and gun violence), nonatopic asthma (eg, early-life SHS and daycare attendance), or both (eg, an unhealthy diet) in Puerto Rican children.

Annual SO2 exposure, asthma, atopy, and lung function in Puerto Rican children.

BACKGROUND: Long-term effects of sulfur dioxide (SO2 ) exposure on children, a vulnerable population, are largely unknown. Further, how long-term SO2 affects Puerto Rican children living in the island of Puerto Rico, a group with high asthma prevalence, is unclear. We evaluated the effects of annual average 1-hour daily maximum SO2 average on asthma, atopy, total immunoglobulin E (IgE), and lung function in Puerto Rican children. METHODS: A cohort of 678 children (351 with asthma, 327 without asthma) was recruited in Puerto Rico from 2009 to 2010. Annual average 1-hour daily maximum SO2 exposure was interpolated utilizing publicly available monitoring data. Multivariable logistic and linear regression was used for the analysis of asthma, atopy (defined as an IgE ≥0.35 IU/mL to at least one of five common aero-allergens), total IgE, and lung function measures (forced vital capacity [FVC], forced expiratory volume in 1 second [FEV1], and FEV1/FVC ratio). RESULTS: Annual SO2 exposure (per 1 ppb) was significantly associated with asthma (odds ratio [OR] = 1.42; 95% confidence interval [CI] = 1.05-1.91) and atopy (OR = 1.35; 95% CI = 1.02-1.78). Such exposure was also significantly associated with lower FEV1/FVC in all children (ß = -1.42; 95% CI = -2.78 to -0.08) and in children with asthma (ß = -2.39; 95% CI= -4.31 to -0.46). Annual SO2 exposure was not significantly associated with total IgE, FEV1, or FVC. CONCLUSIONS: Among Puerto Rican children in Puerto Rico, long-term SO2 exposure is linked to asthma and atopy. In these children, long-term SO2 exposure is also associated with reduced FEV1/FVC, particularly in those with asthma.

Exposure to gun violence and asthma among children in Puerto Rico.

BACKGROUND AND OBJECTIVES: Although community violence may influence asthma morbidity by increasing stress, no study has assessed exposure to gun violence and childhood asthma. We examined whether exposure to gun violence is associated with asthma in children, particularly in those reporting fear of leaving their home. METHODS: Case-control study of 466 children aged 9-14 years with (n = 234) and without (n = 232) asthma in San Juan, Puerto Rico. Lifetime exposure to gun violence was defined as hearing a gunshot more than once. We also assessed whether the child was afraid to leave his/her home because of violence. Asthma was defined as physician-diagnosed asthma and wheeze in the prior year. We used logistic regression for the statistical analysis. All multivariate models were adjusted for age, gender, household income, parental asthma, environmental tobacco smoke, prematurity and residential distance from a major road. RESULTS: Cases were more likely to have heard a gunshot more than once than control subjects (n = 156 or 67.2% vs. n = 122 or 52.1%, P < 0.01). In a multivariate analysis, hearing a gunshot more than once was associated with asthma (odds ratio [OR] = 1.8, 95% confidence interval [CI] = 1.1-1.7, P = 0.01). Compared with children who had heard a gunshot not more than once and were not afraid to leave their home because of violence, those who had heard a gunshot more than once and were afraid to leave their home due to violence had 3.2 times greater odds of asthma (95% CI for OR = 2.2-4.4, P < 0.01). CONCLUSIONS: Exposure to gun violence is associated with asthma in Puerto Rican children, particularly in those afraid to leave their home. Stress from such violence may contribute to the high burden of asthma in Puerto Ricans.