Inadequate therapy for asthma among children in the United States.

OBJECTIVE: Childhood asthma morbidity and mortality are increasing despite improvements in asthma therapy. We hypothesized that a substantial number of children with moderate to severe asthma are not taking the maintenance medications recommended by national guidelines. The objective of this study was to describe medication use among US children with asthma and determine risk factors for inadequate therapy. METHODS: The National Health and Nutrition Examination Survey (NHANES) III 1988-1994 provided cross-sectional, parent-reported data for children 2 months to 16 years of age. Analysis focused on children with moderate to severe asthma (defined as having any hospitalization for wheezing, >/=2 acute visits for wheezing, or >/=3 episodes of wheezing over the past year). We defined these children as adequately treated if they had taken a maintenance medication (inhaled corticosteroid, cromolyn, or theophylline) during the past month. Demographic variables were analyzed for independent associations with inadequacy of therapy. The statistical analysis used SUDAAN software to account for the complex sampling design. RESULTS: A total of 1025 children (9.4%) had physician-diagnosed asthma. Of those with moderate to severe asthma (n = 524), only 26% had taken a maintenance medication during the past month. Even among children with 2 or more hospitalizations over the previous year, only 32% had taken maintenance medications. In a logistic regression analysis, factors significantly associated with inadequate therapy included: age

Tobacco and children. An economic evaluation of the medical effects of parental smoking.

OBJECTIVE: To determine the economic influence of pediatric disease attributable to parental smoking. DATA SOURCES: Computerized bibliographic databases were searched. Subject headings included asthma, burn, cost, low birth weight, otitis media, respiratory syncytial virus bronchiolitis, sudden infant death syndrome, and tobacco smoke pollution. The following constraints were applied to the published articles we studied: publication time, January 1980 through May 1996; age range of children studied, neonate to 18 years; and written in English. Articles used specifically as references for cost issues were limited to studies performed in the United States. DATA EXTRACTION: This study is a literature synthesis, which uses as its primary source the results of previously published best estimates. This is not a meta-analysis of studies analyzing the relationships between childhood disease and smoking. RESULTS: Using data for relative risk, prevalence, and cost of illness and death, we calculated the attributable risk fraction and corresponding direct medical expenditures and costs for loss of life. Costs are adjusted to 1993 dollars. Estimated annual excess cases of childhood illness and death attributable to parental smoking include low birth weight (46,000 cases, 2800 perinatal deaths), sudden infant death syndrome (2000 deaths), respiratory syncytial virus bronchiolitis (22,000 hospitalizations, 1100 deaths), acute otitis media (3.4 million outpatient visits), otitis media with effusion (110,000 tympanostomies), asthma (1.8 million outpatient visits, 14 deaths), and fire-related injuries (10,000 outpatient visits, 590 hospitalizations, and 250 deaths). CONCLUSIONS: Parental smoking is an important preventable cause of morbidity and mortality among American children; it results in annual direct medical expenditures of $4.6 billion and loss of life costs of $8.2 billion. Additional efforts to reduce children's exposure to tobacco smoke are warranted.

School readiness among urban children with asthma.

BACKGROUND: Children with chronic illnesses, including asthma, are at risk for school problems. Developmental problems, however, may begin before school entry, and the developmental status of preschool children with asthma has not been evaluated. OBJECTIVE: To test the hypothesis that urban preschool children with asthma have lower parent-reported developmental scores compared with children without asthma. METHODS: A comprehensive survey of children beginning kindergarten in 1998 in the urban school system in Rochester, NY, collected parent reports of demographic, medical, and developmental data. We compared children with asthma with and without limitation of activity to children without asthma for motor, language, socioemotional, and school readiness skills and the need for extra help with learning. Linear and logistic regression were used to determine associations between asthma and developmental outcomes. RESULTS: Among the 1058 children in this sample, 9% had asthma, including 5% with asthma with limitation of activity. After adjustment for multiple potential confounding variables, the children with asthma with limitation had lower scores on school readiness skills compared with children without asthma (2.0 vs 2.5, P <.001). Further, the parents of children with asthma with limitation were substantially more likely (P <.05) to describe them as needing extra help with learning (74% vs 56%; odds ratio, 3.2; 95% confidence interval, 1.5--7.8). CONCLUSIONS: Urban preschool children with significant asthma had poorer parent-reported school readiness skills and a greater need for extra help with learning compared with children without asthma. This finding suggests that developmental problems for children with asthma may begin before school entry.

Risk factors for pediatric asthma. Contributions of poverty, race, and urban residence.

The Child Health Supplement to the 1988 National Health Interview Survey was used to examine parent-reported current asthma among a nationally representative sample of 17,110 children zero to 17 yr of age. Numerous demographic variables were analyzed for independent associations with asthma using modified stepwise logistic regression, with models including specific combinations of risk factors. Black children had higher rates of asthma than did white children in unadjusted analyses, but after controlling for multiple factors, black race was not a significant correlate of asthma (adjusted odds ratio = 0.87, 95% CI = 0.63 to 1.21). Compared with nonurban white children, urban children, both black and white, were at significantly increased risk of asthma: urban and black (adjusted OR = 1.45, 95% CI = 1.14 to 1.86), urban and white (adjusted OR = 1.22, 95% CI = 1.01 to 1.48), whereas nonurban black children were not: nonurban and black (adjusted OR = 1.15, 95% CI = 0.83 to 1.61). Similarly, compared with nonurban, nonpoor children, urban and poor (adjusted OR = 1.44, 95% CI = 1.05 to 1.95), urban and nonpoor (adjusted OR = 1.22, 95% CI = 1.004 to 1.48), urban children, both poor and nonpoor, were at significantly increased risk of asthma, whereas nonurban poor children were not: nonurban and poor (adjusted OR = 1.03, 95% CI = 0.72 to 1.48). These results suggest that the higher prevalence of asthma among black children is not due to race or to low income per se, and that all children living in an urban setting are at increased risk for asthma.

Effectiveness of influenza vaccine for the prevention of asthma exacerbations.

BACKGROUND: There is a lack of clinical evidence that annual vaccination against influenza prevents asthma exacerbations in children. METHODS: Retrospective cohort study of 800 children with asthma, where one half did, and the other half did not receive the influenza vaccine. The two groups were compared with respect to clinic visits, emergency department (ED) visits, and hospitalisations for asthma. In multivariable analyses, adjustment was made for baseline asthma severity, prior utilisation of health services, receipt of vaccine in the previous year, and demographic variables. RESULTS: After adjusting for other variables, the vaccine group had a significantly increased risk of asthma related clinic visits and ED visits (odds ratios 3.4 and 1.9, respectively). CONCLUSION: This study failed to provide evidence that the influenza vaccine prevents paediatric asthma exacerbations.

Residential exposures associated with asthma in US children.

OBJECTIVE: Residential exposures are recognized risk factors for childhood asthma, but the relative contribution of specific risk factors and the overall contribution of housing to asthma in US children is unknown. The objective of this study was to identify risk factors and estimate the population attributable risk of residential exposures for doctor-diagnosed asthma for US children. METHODS: A cross-sectional survey was conducted from 1988 to 1994. Survey participants were 8257 children who were <6 years old and who participated in the Third National Health and Nutrition Examination Survey, a survey of the health and nutritional status of children and adults in the United States. The main outcome measure was doctor-diagnosed asthma, as reported by the parent. RESULTS: Six percent of children had doctor-diagnosed asthma. The prevalence of asthma was higher among boys (6.7%) than girls (5.1%) and was higher among black children (8.9%) than white children (5.2%). Risk factors for doctor-diagnosed asthma included a family history of atopy (odds ratio [OR]: 2.2; 95% confidence interval [CI]: 1.5, 3.1), child's history of allergy to a pet (OR: 24.2; 95% CI: 8.4, 69.5), exposure to environmental tobacco smoke (OR: 1.8; 95% CI: 1.2-2.6), use of a gas stove or oven for heat (OR: 1.8; 95% CI: 1.02-3.2), and presence of a dog in the household (OR: 1.6; 95% CI: 1.1, 2.3). The population attributable risk of >/=1 residential exposure for doctor-diagnosed asthma in US children <6 years old was 39.2%, or an estimated 533 000 excess cases, whereas having a family history of atopy accounted for 300 000. The attributable cost of asthma as a result of residential exposures for children <6 years old was $402 million (95% CI: $296-$507 million) annually. CONCLUSIONS: The elimination of identified residential risk factors, if causally associated with asthma, would result in a 39% decline in doctor-diagnosed asthma among US children <6 years old.

Iron deficiency and cognitive achievement among school-aged children and adolescents in the United States.

CONTEXT: Iron deficiency anemia in infants can cause developmental problems. However, the relationship between iron status and cognitive achievement in older children is less clear. OBJECTIVE: To investigate the relationship between iron deficiency and cognitive test scores among a nationally representative sample of school-aged children and adolescents. DESIGN: The National Health and Nutrition Examination Survey III 1988-1994 provides cross-sectional data for children 6 to 16 years old and contains measures of iron status including transferrin saturation, free erythrocyte protoporphyrin, and serum ferritin. Children were considered iron-deficient if any 2 of these values were abnormal for age and gender, and standard hemoglobin values were used to detect anemia. Scores from standardized tests were compared for children with normal iron status, iron deficiency without anemia, and iron deficiency with anemia. Logistic regression was used to estimate the association of iron status and below average test scores, controlling for confounding factors. RESULTS: Among the 5398 children in the sample, 3% were iron-deficient. The prevalence of iron deficiency was highest among adolescent girls (8.7%). Average math scores were lower for children with iron deficiency with and without anemia, compared with children with normal iron status (86.4 and 87.4 vs 93.7). By logistic regression, children with iron deficiency had greater than twice the risk of scoring below average in math than did children with normal iron status (odds ratio: 2.3; 95% confidence interval: 1.1-4.4). This elevated risk was present even for iron-deficient children without anemia (odds ratio: 2.4; 95% confidence interval: 1.1-5.2). CONCLUSIONS: We demonstrated lower standardized math scores among iron-deficient school-aged children and adolescents, including those with iron deficiency without anemia. Screening for iron deficiency without anemia may be warranted for children at risk.