Environmental tobacco smoke as a risk factor for respiratory disease in children

Respiratory diseases are a frequent reason for using health care. In 1995-1996, diseases of the respiratory tract (ICD 460-519) contributed seven of the top 15 reasons for visits to physician offices among children under 15 years of age in the United States. Environmental tobacco smoke (ETS) is a wide-spread environmental pollutant that has been long linked with respiratory problems. This paper will review the available literature on the role ETS plays in respiratory diseases, including asthma. This review focuses not only on the respiratory problems caused by ETS, but also examines the influence of age at exposure on the consequences of ETS and the importance of the differing sources of ETS exposure. As ETS is a completely preventable form of environmental pollution, the success or failure of various types of interventions will also be reviewed.

Understanding the economic burden of asthma

The economic impact of asthma is large and growing, and the use of economic outcomes is increasing. Such outcomes serve as the basis for studies of the efficiency of care and are being reported increasingly as outcomes of clinical trials. This article presents the basic components of a cost-of-illness study, the in-fluences that have an impact on these components, the relation of economic indicators to clinical outcomes, and the relative importance of the economic factors for differing groups in society.

Health status of the Pakistani population: a health profile and comparison with the United States

OBJECTIVES

The health status of the Pakistani population was compared with that of the US population to provide a better understanding of the health problems in a developing nation and shed light on the dynamics of selected diseases.

METHODS

Results from the National Health Survey of Pakistan (n = 18,315) and the US National Health and Nutrition Examination Survey (n = 31,311) were compared. Standardized and comparable methods were used in both surveys.

RESULTS

Indicators of undernutrition among children were high throughout Pakistan. Among adults, there were urban-rural differences and economic gradients in indicators of undernutrition and risk factors for heart disease and cancer. In comparison with the US population, the Pakistani population has a higher rate of undernutrition, a lower rate of high cholesterol, and an approximately equal rate of high blood pressure.

CONCLUSIONS

There are major inequalities in health within Pakistan and between Pakistan and the United States. Standardized national health examination survey methodology can be used to monitor health status and plan health transition policy in developing countries.

Differences in asthma prevalence between samples of American Indian and Alaska Native children

OBJECTIVES

To better understand the prevalence of asthma among American Indian and Alaska Native (AI/AN) children and to explore the contribution of locale to asthma symptoms and diagnostic assignment, the authors surveyed AI/AN middle school students, comparing responses from metropolitan Tacoma, Washington (metro WA) and a non-metropolitan area of Alaska (non-metro AK).

METHODS

Students in grades 6-9 completed an asthma screening survey. The authors compared self-reported rates of asthma symptoms, asthma diagnoses, and health care utilization for 147 children ages 11-16 self-reporting as AI/AN in metro WA and 365 in non-metro AK.

RESULTS

The prevalences of self-reported asthma symptoms were similar for the metro WA and non-metro AK populations, but a significantly higher percentage of metro WA than of non-metro AK respondents reported having received a physician diagnosis of asthma (OR 2.33; 95% CI 1.23, 4.39). The percentages of respondents who reported having visited a medical provider for asthma-like symptoms in the previous year did not differ.

CONCLUSIONS

The difference in rates of asthma diagnosis despite similar rates of asthma symptoms and respiratory-related medical visits may reflect differences in respiratory disease patterns, diagnostic labeling practices, or environmental factors. Future attempts to describe asthma prevalence should consider the potential contribution of non-biologic factors such as diagnostic practices.

Is allergen skin test reactivity a predictor of mortality? Findings from a national cohort

BACKGROUND

The importance of atopy on subsequent mortality is controversial. A clearer understanding is important as atopy is increasing worldwide.

OBJECTIVE

To determine the influence of allergen skin test reactivity on observed mortality of a national cohort.

METHODS

Baseline health status and atopic status (allergen skin testing) was measured as part of the second National Health and Nutrition Examination Survey (NHANES II), a representative sample of the US population, during the years 1976-80. Vital status and cause of death were assessed through December 31, 1992 for all examinees 30 years of age or older at baseline (n = 9252) as part of the NHANES II Mortality Study (NH2MS). The analytic sample contained 8179 men and women after excluding missing data. Allergen skin test reactivity was defined as weal >/= 3 mm to one of eight 1 : 20 (w/v), 50% glycerinated ('No US Standard of Potency') allergens licensed by the FDA: house dust, cat, dog, Alternaria, mixed giant/short ragweed, oak, perennial rye grass, and Bermuda grass. Survival analyses were conducted using multivariate adjusted Cox regression models to evaluate the association between atopy and all-cause, cardiovascular, and cancer mortality.

RESULTS

There was no association between allergen skin test reactivity and all cause mortality: 30-44 years RR = 1.07 (95% CI 0.63-1.84); 45-59 years RR = 1.10 (0.78-1.55); 60-75 years RR = 1.07 (0.91-1.25). Results were unchanged when cancer or heart disease mortality were examined separately. The presence or absence of allergic symptoms, using the flare to define skin test reactivity, eliminating deaths in the first 5 years of follow-up, or eliminating individuals with pre-existing conditions did not alter the findings.

CONCLUSIONS

Atopy, defined by allergen skin test reactivity, with or without symptoms, is not a predictor of subsequent mortality.

A randomized clinical trial to reduce asthma morbidity among inner-city children: results of the National Cooperative Inner-City Asthma Study

OBJECTIVE

To evaluate a family-focused asthma intervention designed for inner-city children 5 to 11 years old with moderate to severe asthma.

STUDY DESIGN

Randomized, multisite, controlled trial to minimize symptom days (wheeze, loss of sleep, reduction in play activity) measured by a 2-week recall assessed at 2-month intervals over a 2-year follow-up period. The intervention was tailored to each family's individual asthma risk profile assessed at baseline.

RESULTS

Averaged over the first 12 months, participants in the intervention group (n = 515) reported 3.51 symptom days in the 2 weeks before each follow-up interview compared with 4.06 symptom days for the control group (n = 518), a difference of 0.55 (95% CI, 0.18 to 0.92, P =.004). The reduction among children with severe asthma was approximately 3 times greater (1.54 d/2 wk). More children in the control group (18.9%) were hospitalized during the intervention compared with children in the intervention group (14. 8%), a decrease of 4.19% (CI, -8.75 to 0.36, P =.071). These improvements were maintained in the intervention group during the second year of follow-up, during which they did not have access to the asthma counselor.

CONCLUSIONS

We demonstrated that an individually tailored, multifaceted intervention carried out by Masters-level social workers trained in asthma management can reduce asthma symptoms among children in the inner city.

Results of the National Cooperative Inner-City Asthma Study (NCICAS) environmental intervention to reduce cockroach allergen exposure in inner-city homes

BACKGROUND

Cockroach allergen is important in asthma. Practical methods to reduce exposure are needed.

OBJECTIVE

We sought to evaluate the effectiveness of house cleaning and professional extermination on lowering cockroach antigen levels in inner-city dwellings.

METHODS

As part of the National Cooperative Inner-City Asthma Study intervention, 265 of 331 families with asthmatic children who had positive skin test responses to cockroach allergen consented to a professional home extermination with 2 applications of a cockroach insecticide (Abamectin, Avert) combined with directed education on cockroach allergen removal. On a random subset of 48 homes undergoing cockroach extermination in the intervention group, Bla g 1 was measured in settled dust from the kitchen, bedroom, and TV/living room. The first sample was collected 1 week before extermination, with additional samples after the exterminations at approximately 2, 6, and 12 months after the first sample. Self-reported problems with cockroaches were collected at baseline and after 12 months of follow-up in both the intervention and control group.

RESULTS

The geometric mean kitchen level of Bla g 1 decreased at 2 months (33.6 U/g) relative to preextermination levels (68.7 U/g, P <.05). The percent of kitchens with over 8 U/g of Bla g 1 followed a similar pattern, but only the decrease from preextermination to 6-month levels was significant (86.8% vs 64.3%, P <.05). By the 12-month visit, the allergen burden had returned to or exceeded baseline levels. Except for an increase in the bedroom at 2 months (8.9 U/g vs 11.1 U/g, P <.05), no other significant change was seen. Only about 50% of the families followed the cleaning instructions; no greater effect was found in these homes. Self-reported problems with cockroaches showed no difference between the intervention and control group after 1 year of follow-up.

CONCLUSIONS

Despite a significant, but short-lived, decrease the cockroach allergen burden remained well above levels previously found to be clinically significant.

Healthcare expenditures for sinusitis in 1996: contributions of asthma, rhinitis, and other airway disorders

BACKGROUND

There have been no recent assessments of the economic burden of sinusitis in the peer-reviewed literature.

OBJECTIVE

We sought to estimate the 1996 total direct health care expenditures for the treatment of sinusitis.

METHODS

This study determined (1) direct expenditures of medical and surgical encounters in which sinusitis was the primary diagnosis and (2) attributable expenditures when related airway diseases were the primary diagnosis and sinusitis was a comorbid condition. An expert panel used the Delphi consensus-building technique to determine the proportions for the latter.

RESULTS

Overall health care expenditures attributable to sinusitis in 1996 were estimated at $5.8 billion, of which $1.8 billion (30.6%) was for children 12 years or younger. A primary diagnosis of acute or chronic sinusitis accounted for 58.7% of all expenditures ($3.5 billion). About 12% each of the costs for asthma and chronic otitis media and eustachian tube disorders were attributed to diagnosis and treatment of comorbid sinusitis. Nearly 90% of all expenditures ($5.1 billion) were associated with ambulatory or emergency department services.

CONCLUSION

The economic burden of sinusitis in the United States is significant. However, the limitations of this type of evaluation suggest the $5.8 billion amount may be an underestimate of the true direct costs.

Direct expenditures for the treatment of allergic rhinoconjunctivitis in 1996, including the contributions of related airway illnesses

BACKGROUND

Previous estimates of the national economic burden of allergic rhinoconjunctivitis (AR/AC) have relied on data analyses in which AR/AC was the primary International Classification of Diseases-ninth revision-Clinical Modification (ICD-9-CM)-coded diagnosis. These studies ignore the costs when AR/AC was a secondary diagnosis to other disorders such as asthma and sinusitis.

OBJECTIVE

We sought to determine the national direct cost of illness for AR/AC.

METHODS

An expert panel used the Delphi technique to estimate the proportion of visits coded by other primary ICD-9-CM diagnoses in which AR/AC was a significant secondary comorbid condition. The costs of this proportion were deemed to be "attributable" to AR/AC and were added to the costs when allergic rhinitis and allergic conjunctivitis were the primary diagnoses.

RESULTS

The cost when AR/AC was the primary diagnosis was $1.9 billion (in 1996 dollars). The cost when AR/AC was a secondary diagnosis was estimated at $4.0 billion, giving an estimate of $5.9 billion for the overall direct medical expenditures attributable to AR/AC. Outpatient services (63%, $3.7 billion), medications (25%, $1.5 billion), and inpatient services (12%, $0.7 billion) accounted for the expenditures. Children 12 years and younger accounted for $2.3 billion (38.0%).

CONCLUSION

Upper airway allergy is an expensive disease process because of its readily apparent manifestations as AR/AC and its contribution to other airway disorders.

Nurse staffing levels and adverse events following surgery in U.S. hospitals

PURPOSE

To examine the relationship between nurse staffing and selected adverse events hypothesized to be sensitive to nursing care, while controlling for related hospital characteristics. Efforts in the United States to reduce hospital costs, resulting in strategies to use fewer nurses, have stimulated extensive debate but little evaluation.

DESIGN

Survey using data from a 20% stratified probability sample to approximate U.S. community hospitals. The sample included 589 acute-care hospitals in 10 states.

METHODS

Discharge data from 1993 for patients aged 18 years and over were used to create hospital-level adverse event indicators. These hospital-level data were matched to American Hospital Association data on community hospital characteristics, including nurse staffing, to examine the relationship between nurse staffing and adverse events.

RESULTS

A large and significant inverse relationship was found between full-time-equivalent RNs per adjusted inpatient day (RNAPD) and urinary tract infections after major surgery (p < .0001) as well as pneumonia after major surgery (p < .001). A significant but less robust inverse relationship was found between RNAPD and thrombosis after major surgery (p < .01), as well as pulmonary compromise after major surgery (p < .05).

CONCLUSIONS

Inverse relationships between nurse staffing and these adverse events provide information for managers to use when redesigning and restructuring the clinical workforce employed in providing inpatient care.

The risk for outpatient antibiotic-treated infections following a course of oral corticosteroids among children with asthma

Short courses of oral corticosteroids are widely used to treat asthma. The objective of this study was to assess if one course of oral corticosteroids increases asthmatic children's risk for infections treated with outpatient antibiotics. Using New York State Medicaid claims data on asthmatic children 2-15 years old, we made cohorts of oral corticosteroid users and nonusers. We determined the percentage of children who filled antibiotic prescriptions in the 30 days after index dates. Index dates were dates oral steroids were started (for steroid users) or matched dates (for nonusers). Odds ratios were adjusted for age, month of index date, and prior antibiotic use. Among children not receiving antibiotics on index dates, antibiotic prescriptions were filled in the next 30 days for 438 (20%) of 2145 steroid nonusers and 130 (19%) of 698 steroid users (p=0.30); compared to nonusers, steroid users had an adjusted odds ratio of subsequent antibiotic use of 0.92 (95% confidence interval [CI] 0.73-1.15). Among children receiving antibiotics on index dates, antibiotic prescriptions were filled in the next 30 days for 116 (26%) of 451 steroid nonusers and 50 (19%) of 260 steroid users (p=0.05); compared to nonusers, steroid users had an adjusted odds ratio of subsequent antibiotic use of 0.65 (95% CI 0.53-0.97). We conclude that one course of oral corticosteroids does not increase asthmatic children's risk for infections treated with outpatient antibiotics.

Race, income, urbanicity, and asthma hospitalization in California: a small area analysis

STUDY OBJECTIVES

To explicate the interrelationship between asthma hospitalization and race/ethnicity and income.

DESIGN

Small area ecologic analysis using census and administrative data.

SETTING AND PARTICIPANTS

All asthma hospitalizations in California were identified using the 1993 California Hospital Discharge file. Small area analyses of Los Angeles (LA) were compared with published rates in New York City (NYC).

RESULTS

In 1993, the age-adjusted asthma hospitalization rate in California for nonelderly blacks was 42.5/10,000-approximately four times higher than other populations. Black rates remained fourfold higher after stratification by age, income, and urbanicity. Multivariate analyses suggest that the association between black race and asthma hospitalization is independent of income. Regardless of race, children and persons living in poverty were at increased risk for asthma hospitalization. Urbanicity was not a predictor for asthma hospitalization. Overall, asthma hospitalization rates in NYC were 2.8 times higher compared with rates in LA; while rates were similar among blacks (60 vs 40/10,000, respectively), Puerto Rican Hispanics in NYC had dramatically higher rates compared with Mexican Hispanics in LA (63 vs 14/10,000, respectively).

CONCLUSIONS

After controlling for socioeconomic status, notable differences in asthma hospitalization by race and ethnicity persist. The reasons for the significantly elevated risk of asthma morbidity among blacks remain unclear.

The burden of environmental tobacco smoke exposure on the respiratory health of children 2 months through 5 years of age in the United States: Third National Health and Nutrition Examination Survey, 1988 to 1994

OBJECTIVE

To measure the effect of environmental tobacco smoke (ETS) on respiratory health in a national sample of young children.

METHODS

The study evaluated children 2 months through 5 years of age participating in the Third National Health and Nutrition Examination Survey, 1988 to 1994. The group was a representative sample of the US population (N = 7680). A parental report of household smoking or maternal smoking during pregnancy ascertained ETS exposure. Respiratory outcomes were based on parental report of wheezing, cough, upper respiratory infection, or pneumonia in the last 12 months and chronic bronchitis or physician-diagnosed asthma at any time. Logistic regression was used to adjust for age, sex, race/ethnicity, birth weight, day care, family history of allergy, breastfeeding, education level of head of household, and household size.

RESULTS

Approximately 38% of children were presently exposed to ETS in the home, whereas 23.8% were exposed by maternal smoking during pregnancy. ETS exposure increased chronic bronchitis and three or more episodes of wheezing among children 2 months to 2 years old and asthma among children 2 months to 5 years old. For household exposure, a consistent effect was seen only at >/=20 cigarettes smoked per day. Adjusted odds ratios for increased risk (95% confidence interval) for household exposures (>/=20 cigarettes smoked per day vs none smoked) and maternal prenatal exposure (prenatal smoking vs no smoking), respectively, for children 2 months to 2 years old were chronic bronchitis, 2.5 (1.6, 4.1); 2.2, (1.6, 3); three or more episodes of wheezing, 2.7 (1.7, 4.2), 2.1 (1. 5, 2.9); and for children 2 months to 5 years old were asthma, 2.1 (1.4, 3.2); 1.8 (1.3, 2.6). Reported use within the past month of prescription medications for asthma (beta-agonists or inhaled steroids) was not different between those with asthma reporting ETS exposure and those reporting no exposure; percent of patients with asthma reporting use of medication by household exposure was 0, 25. 7%; 1 to 19 cigarettes smoked per day, 32.9%; and >/=20 cigarettes smoked per day, 23.1%; percent of patients with asthma reporting use of medication by maternal smoking during pregnancy was no, 28.9%; yes, 22.7%. Among children 2 months to 2 years of age exposed to ETS, 40% to 60% of the cases of asthma, chronic bronchitis, and three or more episodes of wheezing were attributable to ETS exposure. For diagnosed asthma among children 2 months through 5 years old, there were 133 800 to 161 600 excess cases. Among exposed children 2 months through 2 years of age, there were 61 000 to 79 200 excess cases of chronic bronchitis and 126 700 to 172 000 excess cases of three or more episodes of wheezing.

CONCLUSIONS

ETS exposure is common among children in the United States. The reported prevalence of asthma, wheezing, and chronic bronchitis was increased with ETS exposures. No statistically significant increase in the prevalence of upper respiratory infection, pneumonia, or cough was associated with ETS exposure. ETS exposure has little effect on the respiratory health of children between 3 and 5 years of age, with the exception of asthma. ETS appears to increase the prevalence of asthma rather than the severity as measured by medication use. These findings reinforce the need to reduce the exposure of young children to ETS.

A synoptic evaluation of asthma hospital admissions in New York City

An evaluation of weather/asthma relationships in the New York City Standard Metropolitan Statistical Area (SMSA) is developed using a synoptic climatological methodology. This procedure isolates "air masses," or bodies of air that are homogeneous in meteorological character, and relates them to daily counts of overnight asthma hospital admissions. The synoptic procedure used here, known as the temporal synoptic index (TSI), can identify air masses in automated fashion for every day over many years. It is apparent that certain air masses are related to statistically significant increases in asthma hospital admissions. The impact varies seasonally, with weather having a particularly important impact on asthma admissions during fall and winter. It appears that air pollution has little impact on asthma during these two seasons, and the air masses associated with the highest admissions are not distinguished by high concentrations of pollutants. However, during spring and summer, the air masses associated with highest admissions are among those with high pollution concentrations. There is a strong interseasonal differential response to weather and air pollution by asthmatics in New York City. If these results can be replicated at other locations in future studies, it may be possible to develop an asthma/weather watch-warning system, based on the expected arrival of high-admissions air masses.

National trends in the mortality of children with sickle cell disease, 1968 through 1992

OBJECTIVES

This paper describes national trends in mortality of children with sickle cell disease and the settings in which death occurred.

METHODS

United States death certificate data from 1968 through 1992 were used to calculate mortality rates of Black children with sickle cell disease 1 to 14 years old. Deaths from trauma, congenital anomalies, and perinatal conditions were excluded.

RESULTS

Between 1968 and 1992, mortality rates of Black children with sickle cell disease decreased 41% for 1- to 4-year-olds, 47% for 5- to 9-year-olds, and 53% for 10- to 14-year-olds. During 1986 through 1992, children who died before hospital admission accounted for 41% of deaths among 1- to 4-year-olds, 27% among 5- to 9-year-olds, and 12% among 10- to 14-year-olds.

CONCLUSIONS

Survival of Black children with sickle cell disease has improved markedly since 1968. A substantial proportion of deaths continue to occur prior to hospital admission. Trends in sickle cell mortality can be monitored inexpensively with death-certificate data.

Cost of hospitalizations associated with sickle cell disease in the United States

OBJECTIVE

This study estimated the number and cost of hospitalizations associated with sickle cell disease in the United States.

METHODS

To estimate the number of hospitalizations per year in the United States of people with sickle cell disease, the authors used data for the years 1989 through 1993 from national hospital discharge surveys conducted by the National Center for Health Statistics. The authors derived cost estimates using data from a 1992 national hospital discharge survey conducted by the Agency for Health Care Policy and Research and a 1992 survey of physicians conducted by the American Medical Association.

RESULTS

During the years 1989 through 1993, there were on average an estimated 75,000 hospitalizations per year of children and adults with sickle cell disease. The average direct cost per hospitalization (in 1996 dollars) was estimated at $6300, for a total direct cost of $475 million per year. In 66% of hospital discharge records, government programs were listed as the expected principal source of payment.

CONCLUSIONS

The cost of hospitalizations associated with sickle cell disease is substantial. Because government programs pay most of this cost, further government-funded research to develop interventions that prevent complications of the disease has great potential for cost savings as well as for reducing the suffering of those afflicted with this painful genetic disorder. These national cost estimates contribute to an understanding of the impact of sickle cell disease and should be useful in establishing research priorities.

Geographic differences in mortality of young children with sickle cell disease in the United States

OBJECTIVES

Because geographic differences in health care have been found for many diseases, including those affecting children, there are probably geographic differences in the health care of young children with sickle cell disease. Consequently, survival of young children with sickle cell disease might differ among geographic areas. This study's objective was to identify areas in the United States where young children with sickle cell disease are at especially high and low risk of dying.

METHODS

Using U.S. death certificate data from 1968 through 1992, the authors calculated the mortality rates of 1- through 4-year-old black children with sickle cell disease for states, counties, and cities. Deaths from trauma, congenital anomalies, and perinatal conditions were excluded.

RESULTS

From 1968 through 1980 and from 1981 through 1992, 1- through 4-year-old black children with sickle cell disease in Florida had a markedly higher risk of dying, and those in Pennsylvania had a markedly lower risk of dying, than the average 1- through 4-year-old black child with the disease in the United States. From 1981 through 1992, 1- through 4-year-old black children with sickle cell disease in Maryland had the lowest mortality rate in the nation. During the same time period, 1- through 4-year-old black children with sickle cell disease in five counties in Florida were at especially high risk, while in Baltimore no young black children with the disease died. These geographic differences in mortality of black children with sickle cell disease greatly exceeded geographic differences in mortality of black children without the disease.

CONCLUSIONS

Marked differences exist across the United States in mortality of young black children with sickle cell disease. To improve survival for children with the disease in high mortality areas, evaluations should be made of the accessibility and quality of medical care, and of parents' health care seeking behavior and compliance with antibiotic prophylaxis. In addition, efforts should be made to understand and duplicate the success of treatment programs in low mortality areas.

Does asthma education equal asthma intervention?

The complex, multifactorial problem of increasing asthma morbidity, especially in minority communities, will not be solved by unidimensional approaches. Appropriately targeted multidimensional intervention programs are needed to control the rising burden of asthma.

A population-based serologic survey of immunity to tetanus in the United States

BACKGROUND

Vaccination rates are frequently considered a surrogate measure of protection. To provide more accurate estimates, serum levels of antibody against tetanus were measured as part of the third National Health and Nutrition Examination Survey (NHANES III), which studied a representative sample of the civilian, noninstitutionalized population of the United States.

METHODS

We measured tetanus antitoxin using a solid-phase enzyme immunoassay in serum samples from 10,618 persons six years of age and older who were examined during phase 1 of NHANES III in 1988 to 1991.

RESULTS

Overall, 69.7 percent of Americans six years of age and older had protective levels of tetanus antibodies (> 0.15 IU per milliliter). The rate decreased from 87.7 percent among those 6 to 11 years of age to 27.8 percent among those 70 years of age or older. Among children 6 to 16 years of age, 82.2 percent had protective levels of tetanus antibodies, with little variation according to race or ethnicity. More men than women were immune (79.0 percent vs. 62.4 percent). Mexican Americans had a significantly lower rate of immunity (57.9 percent, P < 0.05) than either non-Hispanic whites (72.7 percent) or non-Hispanic blacks (68.1 percent). Those with a history of military service, higher levels of education, or incomes above the poverty level were more likely to have protective antibody levels. Although the prevalence of immunity declined rapidly starting at the age of 40 years, most of the 107 cases of tetanus (with 20 deaths) reported in 1989 and 1990 occurred in persons 60 years of age or older.

CONCLUSIONS

Despite the fact that effective vaccines against tetanus have been available since the 1940s, many Americans do not have immunity to tetanus, and the rates are lowest among the elderly. There is an excellent correlation between vaccination rates (96 percent) and immunity (96 percent) among six-year-olds. However, antibody levels decline over time, and one fifth of older children (10 to 16 years of age) do not have protective antibody levels.

Health and social characteristics and children's cognitive functioning: results from a national cohort

OBJECTIVES

The purpose of this study was to examine the associations between cognitive functioning in children and sociodemographic, family, and health characteristics.

METHODS

Data from phase 1 of the third National Health and Nutrition Examination Survey were used to evaluate performance on standardized cognitive tests in a representative sample of 2531 children 6 to 16 years of age. Multivariate analyses were used to assess independent associations between covariates and test performance.

RESULTS

Lower income, minority status, and lower education of an adult reference person (one of the persons in the household who owned or rented the home) were independently associated with poorer performance on all cognitive subtests. To a lesser degree, general health status, history of birth complications, and sex also were independent predictors of performance for some of the subtests.

CONCLUSIONS

These findings illustrate disparities in cognitive functioning across sociodemographic and health characteristics of children in the US population. They suggest the need for public health policies to take a multifaceted approach to optimizing childhood environments in order to overcome the effects of socioeconomic and minority status.

Self-described weight status of Mexican-American adolescents

PURPOSE

To evaluate Mexican-American adolescents' descriptions of their weight status.

METHODS

Data were from the Hispanic Health and Nutrition Examination Survey, conducted in 1982-1983 among Mexican-Americans in five southwestern states. The current study used data on 429 males and 485 non-pregnant females 12-19 years old. In an interview, participants were asked to describe their weight status (underweight, about the right weight, overweight); in an examination (performed two to four weeks after the interview), weights and heights were measured. Each participant's body-mass index (weight/height2) was calculated, and single year of age-and-sex-specific BMI cutoffs were used to determine each participant's BMI decile.

RESULTS

The overweight description was chosen by 46% of females and 23% of males, and the underweight description by 7% of females and 17% of males. The percentage of adolescents self-described as overweight rose with increasing BMI percentile, the rise starting in the 30-39th percentiles for females and in 60-69th percentiles for males.

CONCLUSIONS

These findings suggest that many Mexican-American adolescents misperceive their weight status.

Mexican-American mothers' reports of the weights and heights of children 6 months through 11 years old

OBJECTIVE

To determine the accuracy of mothers' reports of their children's weights and heights.

DESIGN AND SETTING

Cross-sectional survey of Mexican Americans in five southwestern states.

SUBJECTS

Interviews were held with mothers of 2,578 children aged 6 months to 11 years old.

MAIN OUTCOME MEASURES

Sensitivity and specificity of categories formed from reported values, and correlation of reported and measured values.

RESULTS

Probability of mothers answering "don't know" was 24% for children's weights and 51% for heights. On the average, mothers overestimated weights at the 15th percentile or lower for age and sex and underestimated weights at the 85th percentile or higher. On the average, they underestimated heights. Categories of low and high weight, height, and body mass index were created by applying absolute-value cutoffs to reported values. All the categories had low sensitivity or specificity. Age-group-specific correlation coefficients between reported and measured values ranged from .79 to .89 for weight and from .32 (for 6- through 23-month-olds) to .70 (for 9- through 11-year-olds) for height.

APPLICATIONS

The use of categories formed by applying absolute-value cutoffs to mother-reported values results in frequent misclassification of individuals. Therefore, such categories should not be used to estimate relative risks associated with weight, height, and body mass index. The good correlation of mother-reported and measured weights indicates that despite their inaccuracies, reported weights well reflect the relative ranking of measured weights. Thus, the use of reported weights as a continuous variable in multivariate analyses might cause only small errors in the coefficient for weight.

Trends in asthma-related admissions among American Indian and Alaskan native children from 1979 to 1989. Universal health care in the face of poverty

OBJECTIVE

To describe changes in asthma-related hospitalizations in Indian Health Service facilities and compare with national trends.

DESIGN

Trend analysis.

PATIENTS AND SETTING

Hospital discharge records of patients aged 17 years and younger treated by the Indian Health Service between 1979 and 1989.

MAIN OUTCOME MEASURES

Patients discharged with asthma as the first listed diagnosis.

RESULTS

The rates of asthma-related hospitalizations increased an average of 2.6% (95% confidence interval [CI], 0.1 to 5.2) per year between 1979 and 1989 among American Indian and Alaskan Native children aged 0 to 17 years. The increase was 3.7% among the 0- to 4-year age group (95% CI, 2.0 to 5.5) and 0.3% (95% CI, 0.26 to 0.3) among the 5- to 17-year age group. Boys tended to have a higher rate of increase (4.3% [95% CI, -0.1 to 8.7]) compared with girls (2.6% [95% CI, -0.2 to 5.4]). The rates for any hospitalization decreased during this period for 0- to 4-year-olds (-7.5% [95% CI, -10.5 to -4.5]). Little change was noted in hospitalization rates for lower respiratory tract diseases. Diagnostic transfer from bronchitis/bronchiolitis to asthma could not explain the increase. Both first admission and readmission for treatment of asthma contributed to the increase. Compared with previously published data, 0- to 4-year-old American Indian and Alaskan Native children more closely approximate white children than black children in both rates of hospitalization (1979-1987) and annual percentage increase in hospitalization (1979-1989 for American Indian and Alaskan Native children and 1979-1987 for white and black children) for the treatment of asthma.

CONCLUSIONS

American Indian and Alaskan Native children who are cared for by the Indian Health Service have asthma-related hospitalization patterns that are similar to those seen in white children despite having socioeconomic characteristics more similar to those of black children.

The weights and heights of Mexican-American adolescents: the accuracy of self-reports

The accuracy of Mexican-American adolescents' self-reported weights, heights, and body mass indexes was evaluated with data from the Hispanic Health and Nutrition Examination Survey. On average, adolescents with low measured body mass indexes and high measured body mass indexes overestimated and underestimated their weights, respectively. Categories of low and high body mass indexes created by applying cutoffs to reported body mass indexes had low sensitivities. For weight, height, and body mass indexes, measured and reported values were highly correlated. This high correlation suggests that adolescents' reported values can be used as continuous variables in multivariate analyses with only small errors resulting in the coefficients for weight, height, and body mass index.

Reported asthma among Puerto Rican, Mexican-American, and Cuban children, 1982 through 1984

Data from the Hispanic Health and Nutrition Examination Survey (HHANES) (1982 through 1984) and the National Health and Nutrition Examination Survey (NHANES) II (1976 through 1980) were used to examine reported physician-diagnosed asthma among 6-month-old through 11-year-old children. The highest prevalence of active asthma was reported for Puerto Ricans: 11.2% compared with 3.3% for non-Hispanic Whites, 5.9% for non-Hispanic Blacks, 2.7% for Mexican Americans, and 5.2% for Cubans. Health services utilization and severity do not appear to explain the differences between Puerto Ricans and Mexican Americans. Educational programs on asthma should consider focusing on Puerto Ricans.

The effect of pulmonary impairment on all-cause mortality in a national cohort

The association between pulmonary impairment and all-cause mortality was investigated among white subjects in a follow-up study of a large national cohort. Pulmonary function was measured during the National Health and Nutrition Examination Survey (NHANESI) (1971 to 1975); subsequent mortality information was obtained from the 1987 NHANES I Epidemiologic Follow-up Study (1982 to 1987). Of 4,764 white sample persons, ages 25 to 74 years examined during NHANES I, 658 (13.8 percent) were identified as having pulmonary impairment defined as a FEV1/FVC < or = 69 percent. A total of 743 (15.6 percent) sample persons died during the follow-up period. The association between pulmonary impairment and all-cause mortality was examined for male and female subjects separately using the Cox proportional hazards model controlling for age, smoking, educational level, body mass index, and respiratory diseases. The analysis suggests that reduced FEV1 percent predicted was a significant risk factor for mortality among both sexes, and the FEV1/FVC ratio was significantly associated with all-cause mortality among male subjects only.

The association of individual allergen reactivity with respiratory disease in a national sample: data from the second National Health and Nutrition Examination Survey, 1976-80 (NHANES II)

The independent association of individual allergen reactivity with respiratory disease was evaluated with use of the second National Health and Nutrition Examination Survey, a sample of the U.S. white civilian population, ages 6 to 24 years (n = 4295). Eight, 1:20 wt/vol, 50% glycerol, unstandardized extracts were administered by prick puncture. Allergen reactivity was reported as the percent with a mean erythema diameter 10.5 mm or greater at 20 minutes. Only the prevalence of asthma and allergic rhinitis increased with the increasing number of positive allergen skin tests. The independent association of individual allergen reactivity with respiratory disease was quantified with logistic models that included other allergen reactivity, age, sex, smoking, and region. Asthma was associated with reactivity to house dust (odds ratio, 2.9; 95% confidence interval [CI] 1.7 to 5) and Alternaria (odds ratio, 5.1; 95% CI: 2.9 to 8.9). Allergic rhinitis was associated with reactivity to ragweed (odds ratio, 2.3; 95% CI: 1.5 to 3.3); ryegrass (odds ratio, 2.8; 95% CI: 1.8 to 4.3); house dust (odds ratio, 2.5; 95% CI: 1.6 to 3.9); Alternaria (odds ratio, 2.3; 95% CI: 1.5 to 3.4). Asthma only (without allergic rhinitis) was associated with dust and Alternaria. Allergic rhinitis only (without asthma) was associated with ryegrass, ragweed, and house dust. When both asthma and allergic rhinitis were present, only house dust and Alternaria remained associated. These findings highlight the association of specific allergens with upper and lower respiratory diseases and the interactions among coexisting respiratory diseases.

Age of onset in childhood asthma: data from a national cohort

There is controversy over the role of age of asthma onset in childhood asthma. Data collected on self-reported physician-diagnosed asthmatic children and young adults aged 6-24 years (N = 352), who participated in the second National Health and Nutritional Examination, 1976-80 (NHANES II), a national sample, were examined to see whether reported age at onset was associated with the future course of the asthma. Three definitions were used for early-onset asthma: asthma beginning before the second birthday, before the third birthday, and before the fourth birthday. Late-onset asthma was defined as asthma beginning on or after the second birthday, the third birthday, and the fourth birthday, respectively. Among 6-14 year olds, late-onset asthmatic subjects as compared with early-onset asthmatic subjects using the three definitions reported more allergic rhinitis OR = 3.79 (95% CI 1.53, 9.41), 3.06 (1.33, 7.07), 2.71 (1.18, 6.22), and were more likely to have at least one positive allergen skin test OR = 2.21 (95% CI 1.02, 4.79), 2.90 (1.29, 6.49), 3.41 (1.50, 7.75). Late-onset asthmatic subjects tended to report that their asthma was active, have more problems during the past 12 months with wheezing, and have lower values for predicted FVC and FEV1. No difference was found in reported chronic rhinitis, sinusitis, other allergies, problems within the last 12 months with cough attacks, or during the past 3 years a period of cough and phlegm lasting more than 3 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

An economic evaluation of asthma in the United States

BACKGROUND

Asthma is a common chronic illness. Recently, increases in morbidity and mortality due to this disease have been reported. We studied the distribution of health care resources used for asthma in order to lay the groundwork for further policy decisions aimed at reducing the economic burden of this disorder.

METHODS

Estimates of direct medical expenditures and indirect costs (in 1985 dollars) were derived from data available from the National Center for Health Statistics. These cost estimates were projected to 1990 dollars.

RESULTS

The cost of illness related to asthma in 1990 was estimated to be $6.2 billion. Inpatient hospital services represented the largest single direct medical expenditure for this chronic condition, approaching $1.6 billion. The value of reduced productivity due to loss of school days represented the largest single indirect cost, approaching $1 billion in 1990. Although asthma is often considered to be a mild chronic illness treatable with ambulatory care, we found that 43 percent of its economic impact was associated with emergency room use, hospitalization, and death. Nearly two thirds of the visits for ambulatory care were to physicians in three primary care specialties--pediatrics, family medicine or general practice, and internal medicine.

CONCLUSIONS

Potential reductions in the costs related to asthma in the United States may be identified through a closer examination of the effectiveness of care associated with each category of cost. Future health policy efforts to improve the effectiveness of primary care interventions for asthma in the ambulatory setting may reduce the costs of this common illness.

Prevalence of upper and lower respiratory conditions in the US population by social and environmental factors: data from the second National Health and Nutrition Examination Survey, 1976 to 1980 (NHANES II)

Data on respiratory conditions reported by sample persons 12 to 74 years of age in NHANES II were examined. The prevalence of upper respiratory conditions varied little between whites (N = 11,260) and blacks (N = 1,482): allergic rhinitis 9.8% versus 8.1%; chronic rhinitis 20.4% versus 19.2%. Except for "allergic rhinitis only," which was increased in whites, no racial differences were found for any upper respiratory condition, singly or in combination. The prevalence of lower respiratory conditions in whites and blacks were: asthma (A) 6.9% versus 9.2% P less than .05, chronic bronchitis (CB) 1.3% versus 0.8% P less than .05, and chronic cough (CC) 1.1% versus 0.7% P greater than .05. There was no racial difference in the prevalence of overall lower respiratory conditions (A + CC + CB). All upper and lower respiratory conditions peaked in 50 to 74-year-olds except for allergic rhinitis only (without asthma) which peaked in 25 to 49-year-olds. Smokers reported all upper and lower respiratory conditions more often than nonsmokers, except for allergic rhinitis only (without asthma), which was reported less often by smokers. Females reported more allergic rhinitis in any combination, while males reported more asthma only (without allergic rhinitis). Sample persons living below poverty reported increased prevalence of chronic rhinitis, asthma, asthma only (without allergic rhinitis), and either allergic rhinitis or asthma. Residents of urban areas reported increased prevalence of allergic rhinitis and allergic rhinitis only (without asthma) while residents of rural areas reported increased prevalence of asthma only (without allergic rhinitis).(ABSTRACT TRUNCATED AT 250 WORDS)

The association of allergen skin test reactivity and respiratory disease among whites in the US population. Data from the Second National Health and Nutrition Examination Survey, 1976 to 1980

Data collected on 12- to 74-year-old whites (N = 10,854) during the second National Health and Nutrition Examination Survey, 1976 to 1980, a sample of the US population, were used to determine the association between various respiratory symptoms and the degree of allergen skin test reactivity. Prick-puncture testing using eight unstandardized allergens was performed. Allergen skin test reactivity was classified by means of the mean diameter of the erythema reaction at the 20-minute reading. Nonreactors were the comparison group. The prevalence of allergic rhinitis increased as allergen skin test reactivity increased, with the odds ratio exceeding 8 for the group with two or more positive test results. The prevalence of asthma increased with increasing allergen skin test reactivity only in nonsmokers. The odds ratio for allergic rhinitis with allergen skin test reactivity was higher with outdoor than indoor allergens. The association of allergic rhinitis with allergen skin test reactivity was higher when a physician had previously diagnosed allergic rhinitis. Chronic rhinitis was not associated with allergen skin test reactivity.

Prevalence of chronic bronchitis among US Hispanics from the Hispanic Health and Nutrition Examination Survey, 1982-84

In the Hispanic Health and Nutrition Examination Survey (HHANES), Puerto Ricans had a higher age-adjusted prevalence of self-reported chronic bronchitis (2.9 percent, 95% CI = 2.2, 3.6) than Mexican Americans (1.7 percent, 95% CI = 1.3, 2.1) or Cubans (1.7 percent, 95% CI = 0.9, 2.5). The prevalence of chronic bronchitis was at least 2 times higher in smokers as compared to nonsmokers among Puerto Ricans and Cubans, but not for Mexican Americans.

Hypertension prevalence and the status of awareness, treatment, and control in the Hispanic Health and Nutrition Examination Survey (HHANES), 1982-84

The prevalence rates of hypertension among adult (ages 18-74) Mexican Americans, Cuban Americans, and Puerto Ricans were estimated using data from the 1982-84 Hispanic Health and Nutrition Examination Survey (HHANES). Hypertension is defined as diastolic greater than or equal to 90 mm Hg, or systolic greater than or equal to 140 mm Hg, or currently taking antihypertensive medication. Among Mexican Americans in the Southwestern United States, 16.8 percent of the males and 14.1 percent of the females were found to be hypertensive. Among Cuban Americans in Dade County, Florida 22.8 percent of the males and 15.5 percent of the females were hypertensive. Among Puerto Ricans in the New York City area 15.6 percent of the males and 11.5 percent of the females were hypertensive. The age-adjusted rates are significantly lower than comparable rates for Whites and Blacks as measured in the second National Health and Nutrition Examination Survey (NHANES II), 1976-80. Control of hypertension in the HHANES populations fall short of the 1990 Objectives for the Nation established by the US Public Health Service 60 percent (34 percent controlled Mexican American hypertensives, 27.8 percent controlled Cuban American hypertensives, and 29 percent controlled Puerto Rican hypertensives.

Changing patterns of asthma hospitalization among children: 1979 to 1987

The National Hospital Discharge Survey was used to evaluate the trends in asthma hospitalizations among children under International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM): 1979 to 1987. During this period, asthma hospitalizations among children aged 0 to 17 years increased 4.5% per annum (95% confidence interval [Cl], 2% to 7.1%). The increase was largest among 0 to 4 year olds, 5.0% per annum (95% Cl, 3.4% to 6.7%), vs 2.9% per annum (95% Cl, -0.3% to 6.2%) observed among 5 to 17 year olds. Among children aged 0 to 4 years, blacks had approximately 1.8 times the increase of whites. During this time, total hospitalizations decreased -4.6% (95% Cl, -6.6% to -2.5%), while admissions for lower respiratory tract disease had a statistically insignificant decrease: -1.3%. Acute and chronic/unspecified bronchitis hospitalizations decreased -6.1% (95% Cl, -9.4% to -2.7%), but this decrease did not begin until 1983. Thus, a shift in coding from bronchitis to asthma does not seem to fully explain the increase.

The risk of adverse reactions from percutaneous prick-puncture allergen skin testing, venipuncture, and body measurements: data from the second National Health and Nutrition Examination Survey 1976-80 (NHANES II)

A sample (N = 16,204) of the U.S. population, 6 to 74 years of age, was examined in NHANES II with a variety of routine medical procedures, including prick-puncture allergen skin testing (AST), venipuncture, and body measurements. Eight unstandardized extracts licensed by the Food and Drug Administration, a positive and negative control, were used. AST was performed to screen the population for immediate hypersensitivity responses to common aeroallergens. No anaphylactic reactions after AST were observed. One asthmatic reaction occurred during venipuncture. Other adverse reactions (ARs) were limited to syncope, near syncope, and malaise. The rates for any AR were venipuncture, 0.49% (95% confidence interval [CI], 0.38% to 0.60%); AST, 0.04% (95% CI, 0.01%-0.08%); body measures, 0.006% (95% CI, 0 to 0.018%). Sex or fasting status had little effect on the occurrence of AR. The age group 20 to 49 years had the highest occurrence of any AR to venipuncture (0.87%; 95% CI, 0.633% to 1.107%). The risk of prick-puncture AST with eight extracts licensed by the Food and Drug Administration is low and similar to other routine medical procedures.

DTP immunization status and tetanus antitoxin titers of Mexican American children ages six months through eleven years

Data from the Mexican American portion of the Hispanic Health and Nutrition Examination Survey (HHANES), conducted in 1982-83, were analyzed for the number of diphtheria, tetanus, and pertussis (DTP) immunizations reported for Mexican American children 6 months-11 years of age and for levels of tetanus antitoxin titers in Mexican American children 4-11 years of age. In Mexican American children 6 months-11 years, 98.2 per cent had one or more DTP immunizations reported (95 per cent CI: 97.5, 98.9%); 85.1 per cent had three or more DTP immunizations reported (95 per cent CI: 83.2, 87.0%). The reported immunization coverage in Mexican American children was corroborated by the tetanus antitoxin titers which were above the minimum protective level (greater than or equal to 0.01 IU/ml) in 99.6 per cent of the 4-11 year olds. Using the American Academy of Pediatrics' (AAP) recommendations for the number of DTP immunizations, 61.1 per cent of the children 6 months-11 years of age had the age-appropriate number of immunizations (95 per cent CI: 58.5, 63.7%). AAP immunization completion rates were higher for children who: had a source of care reported (62.1 vs 44.3%; 95% CI of the difference: 7.1, 28.5); had insurance coverage (63.5 vs 56.1%; 95% CI of the difference: 2, 12.8); lived in a standard metropolitan statistical area (SMSA)-not central city as compared to SMSA-central city or not SMSA (66.6 vs 57.1%; 95% CI of the difference: 4.3, 14.7); and had 12 or more completed years of education for the head of the household (65.4 vs 58.3%; 95% CI of the difference: 1.8, 12.4).(ABSTRACT TRUNCATED AT 250 WORDS)

National survey of prevalence of asthma among children in the United States, 1976 to 1980

The trend in the prevalence of reported asthma was determined from data collected by the National Center for Health Statistics. The reported prevalence of ever having asthma increased among 6- to 11-year-old children between the first (1971 to 1974) and second (1976 to 1980) National Health and Nutrition Examination Surveys (4.8% to 7.6%, P less than .01). The epidemiology of asthma among children and adolescents 3 to 17 years of age in the United States was examined using data collected in the second National Health and Nutrition Examination Survey. In this paper, asthma is defined as current disease diagnosed by a physician and/or frequent trouble with wheezing during the past 12 months, not counting colds or the flu. Asthma was reported for 6.7% of youths overall and was higher in black than white children (9.4% v 6.2%, P less than .01), boys than girls (7.8% v 5.5%, P less than .01), and urban than rural areas (7.1% v 5.7%, P less than .05). Asthmatic children had a higher prevalence of other allergies (42.6% v 13.2%, P less than .01) and of allergen skin test reactivity (44.5% v 20.7%, P less than .01) than nonasthmatic children. Most asthmatics had their first asthmatic episode before their third birthday. No effect of socioeconomic status on the prevalence of asthma was noted.

The prevalence of allergic skin test reactivity to eight common aeroallergens in the U.S. population: results from the second National Health and Nutrition Examination Survey

Immediate hypersensitivity skin tests to eight select allergens were performed on a sample (N = 16,204) of the civilian noninstitutional population of the United States, 6 to 74 years of age, in the second National Health and Nutrition Examination Survey (NHANES II). The eight allergens were house dust, cat, dog, Alternaria, mixed giant/short ragweed, oak, perennial ryegrass, and Bermuda grass. Skin test reactivity was defined as a mean erythema diameter greater than or equal to 10.5 mm at the 20-minute reading. Overall, 20.2% of the participants reacted to at least one allergen. Peak reactivity occurred in the 12 to 24-year-old age group. Reactivity was higher in blacks versus whites, but the difference did not reach statistical significance (23.2% versus 19.8%; p greater than 0.05). Male participants had an increased prevalence of reactivity versus female participants in whites (22.0% versus 17.6%), but not in blacks (23.2% versus 23.3%). Skin test reactivity increased in both whites and blacks with increasing income and education. The prevalence of skin test reactivity was higher in urban versus rural areas, but the difference was statistically significant only for whites (whites, 21.6% versus 16.4%; blacks, 23.8% versus 18.4%; p greater than 0.05). With logistic regression, the most important predictors of skin test reactivity in whites were age, sex, urban residence, and poverty status. In blacks, the most important predictors were age, urban residence, and poverty status.

National trends in the morbidity and mortality of asthma in the US. Prevalence, hospitalization and death from asthma over two decades: 1965-1984

National population-based data systems of the National Center for Health Statistics (NCHS) were used to study the epidemiology of asthma in the United States over the last 20 years. Asthma is more prevalent among males, those living below the poverty level, persons living in the South and West, and blacks; however, this difference did not attain statistical significance. Death rates from asthma among the older age groups probably increased between 1968 and 1982, with a substantial increase since 1979. For children, the evidence is less clear, but the death rate has increased for children over five years of age during the period from 1979 to 1982. Between 1964 and 1980, asthma has become more prevalent in children under 17 years of age, but this does not reflect an increase in the severity of asthma over this same time period. Hospitalization rates for asthma between 1965 and 1983 increased by 50 percent in adults and by over 200 percent in children. Rates for black patients are 50 percent higher in adults and 150 percent greater in children. It is concluded that there has been a marked increase in hospitalization rates for asthma, a moderate increase in death rates from asthma and a smaller increase in overall prevalence of the disease in the United States.