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S T Weiss

Publications and source records attributed to S T Weiss.

At least 73 records · Page 4Linked to original sources

Asthma pharmacotherapy and utilization by children in 3 managed care organizations. The Pediatric Asthma Care Patient Outcomes Research Team.

BACKGROUND: Asthma is the most common chronic disease among children and the most frequent cause of hospitalization. Appropriate pharmacotherapy is a cornerstone of published national guidelines for the care of children with asthma. OBJECTIVE: The goal was to compare the baseline pharmacotherapy and health care utilization from 1996 to 1997 in children with asthma at managed care organizations (MCOs). METHODS: A common protocol was used to extract the study sample from 3 MCOs with automated claims and pharmacy databases. Children were selected if they were 3 to 15 years old as of June 1997 with 1 or more encounters (outpatient, emergency department visit, hospitalization) with an asthma diagnosis in the previous year. RESULTS: Of the 13,352 children studied, less than 40% were given controllers during the 12-month interval, with ranges of 15% to 77% by level of bronchodilator use, 31% to 44% by age, and 38% to 42% by MCO. Among children given 6 or more bronchodilators, controller dispensing ranged from 73% to 89% among the 3 MCOs. Variability was most evident for inhaled corticosteroids, for which dispensing ranged from 51% to 70%. Rates of asthma hospitalization and emergency department visits also differed among the MCOs, ranging from 21 to 37 per 1000 person-years and 37 to 142 per 1000 person-years, respectively. CONCLUSION: Five years after dissemination of national guidelines for care, the pattern of asthma therapy does not reflect guideline recommendations. Variation among health care organizations with respect to asthma therapy and utilization of health services exists. In addition, controller medications may not be used by all children who could benefit from them.

Administration, Inhalation↗

Eosinophilia is associated with increased all-cause mortality after a follow-up of 30 years in a general population sample.

We investigated whether allergy is associated with increased all-cause mortality. Two allergy markers, peripheral blood eosinophilia (> or =275 eosinophilic cells per mm3) and positive skin tests (sum score > or =3), were available for 5,383 subjects of a cohort study on asthma and chronic obstructive pulmonary disease in general population samples of Vlagtwedde and Vlaardingen, the Netherlands, in 1965-1972. During 30 years of follow-up, 1,135 subjects died. In a Cox regression analysis, eosinophilia was associated with an increased risk (relative risk = 1.4; 95% confidence interval = 1.2-1.7) of all-cause mortality, independent of gender, age, smoking habits, percentage predicted forced expiratory volume in 1 second (FEV1 % predicted), and positive skin tests at the start of the study. Subjects with positive skin tests had only an increased risk of all-cause mortality in the subgroup of subjects with FEV1 <80% of predicted (relative risk = 1.7; 95% confidence interval = 1.0-2.8). These results remained essentially unchanged after exclusion of subjects with asthma. We conclude that eosinophilia is associated with increased all-cause mortality. An increased number of peripheral blood eosinophils may reflect an increased inflammatory response, resulting in tissue injury. It is possible that the association between a low FEV1% predicted and all-cause mortality is partly mediated by an atopic constitution.

Adolescent↗

Relationship between increased airway responsiveness and asthma severity in the childhood asthma management program.

The relationship between increased airway responsiveness and asthma severity in children is unclear. The Childhood Asthma Management Program (CAMP) with 1,041 children with mild to moderate asthma offers an opportunity to relate the concentration of methacholine that causes a 20% fall in FEV(1) (PC(20)) to level of lung function, occurrence of respiratory symptoms, duration of disease, and assessment of severity by clinical staff. Decreasing PC(20) was found to be associated with lower levels of lung function (prebronchodilator percent predicted FEV(1): r = 0.29, beta = 3.5, p < 0.001), the occurrence of chronic asthma symptoms, persistent wheezing (odds ratio [OR] = 1.66, p < 0.001), subjective clinical staff assessment of asthma severity (p < 0.001), and longer duration of asthma (r = -0.11, beta = -0.20, p < 0.002). These data provide evidence that the degree of airway responsiveness is linked to disease severity in children with mild to moderate asthma.

Adolescent↗

The effect of polymorphisms of the beta(2)-adrenergic receptor on the response to regular use of albuterol in asthma.

Inhaled beta-adrenergic agonists are the most commonly used medications for the treatment of asthma although there is evidence that regular use may produce adverse effects in some patients. Polymorphisms of the beta(2)-adrenergic receptor (beta(2)-AR) can affect regulation of the receptor. Smaller studies examining the effects of such polymorphisms on the response to beta-agonist therapy have produced inconsistent results. We examined whether polymorphisms at codon 16 (beta(2)-AR-16) and codon 27 (beta(2)-AR-27) of the beta(2)-AR might affect the response to regular versus as-needed use of albuterol by genotyping the 190 asthmatics who had participated in a trial examining the effects of regular versus as needed albuterol use. During the 16-wk treatment period there was a small decline in morning peak expiratory flow in patients homozygous for arginine at B(2)-AR-16 (Arg/Arg) who used albuterol regularly. This effect was magnified during a 4-wk run out period, during which all patients returned to using as-needed albuterol, so that by the end of the study Arg Arg patients who had regularly used albuterol had a morning peak expiratory flow 30. 5 +/- 12.1 L/min lower (p = 0.012) than Arg/Arg patients who had used albuterol on an as needed basis. There was no decline in peak flow with regular use of albuterol in patients who were homozygous for glycine at beta(2)-AR-16. Evening peak expiratory flow also declined in the Arg/Arg patients who used albuterol regularly but not in those who used albuterol on an as-needed basis. No significant differences in outcomes between regular and as-needed treatment were associated with polymorphisms at position 27 of the beta(2)-AR. No other differences in asthma outcomes that we investigated occurred in relation to these beta(2)-AR polymorphisms. Polymorphisms of the beta(2)-AR may influence airway responses to regular inhaled beta-agonist treatment.

Adolescent↗

Application of an algorithm for the diagnosis of asthma in Chinese families: limitations and alternatives for the phenotypic assessment of asthma in family-based genetic studies.

Phenotype assessment is a crucial issue in gene mapping studies of asthma. Recently, Panhuysen and coworkers proposed an algorithm to define the asthma phenotype in gene mapping family-based studies. We classified members of 2,756 Chinese families ascertained on the basis of the presence of two or more siblings and no more than one parent with asthma using a slightly modified version of the aforementioned algorithm. Among 4,097 Chinese parents, 404 (9.9%) were classified as having "definite asthma," 284 (6.9%) as "probable asthma," 1,193 (29.1%) as "unclassifiable obstructive airway disease, " 626 (15.3%) as "COPD," and 1,590 (38.8%) as "unaffected" (no obstructive airway disease). Among 6,424 Chinese offspring, 1,065 (16.6%) were classified as having "definite asthma," 820 (12.8%) as "probable asthma," 1,996 (31.1%) as "unclassifiable obstructive airway disease," 228 (3.5%) as "COPD," and 2,315 (36%) as "unaffected." The use of the algorithm proposed by Panhuysen and coworkers in a Chinese population with a high prevalence of smoking would result in the exclusion of subjects with asthma who smoke or who have severe airflow obstruction from linkage analysis, as well as in an inability to explore any potential interactions between genetic factors and cigarette smoking in the pathogenesis of asthma. In the absence of a "gold standard," definitions of asthma that incorporate a combination of respiratory symptoms, increased airway responsiveness or bronchodilator response, and a physician's diagnosis of asthma are reasonable. The choice of a particular diagnostic algorithm for family-based genetic studies of asthma should be made according to factors such as the prevalence of smoking in the study population. Genetic studies of intermediate phenotypes related to asthma, which are objectively defined and may be influenced by a smaller number of genes, continue to be of great importance.

Adolescent↗

Familial aggregation of bronchodilator response: a community-based study.

We investigated familial aggregation of bronchodilator response (BDR) among 4,946 subjects selected from 1,161 index families with asthma in a rural community in China. Each family unit consisted of both parents and their first and subsequent offspring, aged 8-20. Raw BDR measurements, defined as the percentage change in FEV(1) after 180 microg of albuterol, were adjusted to account for sex, age, height, weight, education, smoking, asthma, wheeze, and allergy status. Using these adjusted BDR values, we found significant correlation for father-first offspring pairs, mother-first offspring pairs, mother-subsequent offspring pairs, and first offspring-subsequent offspring pairs. The overall magnitude of the correlation coefficient (0.088-0.165) suggests a modest degree of familial clustering. The largest odds ratio was seen for subsequent offspring who had mothers and first offspring with adjusted BDR values above the median: 3.10 (95% CI: 1.85-5.20) in these index families with asthma. Thus, our data support a significant familial aggregation of BDR in this Chinese population, which points to a role of genetic factors in BDR.

Administration, Inhalation↗

Gender-related differences in severe, early-onset chronic obstructive pulmonary disease.

Men have higher prevalence rates of chronic obstructive pulmonary disease (COPD) than women, which has been attributed to the historically higher rates of cigarette smoking in males. However, the increased rates of cigarette smoking in females within the last several decades have been associated with steadily increasing rates of COPD in women. As part of a study of the genetics of severe, early-onset COPD, we assembled a group of 84 probands with severe, early-onset COPD (without severe alpha(1)-antitrypsin deficiency) and 348 of their first-degree relatives. We found a markedly elevated prevalence (71.4%) of females among the early-onset COPD probands. Among the entire group of first-degree relatives of early-onset COPD probands, univariate analysis demonstrated similar spirometric values and bronchodilator responsiveness in males and females; however, among current or ex-smokers, female first-degree relatives had significantly lower FEV(1)/ FVC (81.4 +/- 17.2% in females versus 87.0 +/- 12.9% in males, p = 0.009) and significantly greater bronchodilator responsiveness (expressed as percentage of baseline FEV(1)) (7.7 +/- 9.4% pred in females versus 4.1 +/- 6.4% pred in males, p = 0.002). Female smoking first-degree relatives were significantly more likely to demonstrate profound reductions in FEV(1) (< 40% pred) than male smoking first-degree relatives (p = 0. 03). Multivariate analysis, performed with generalized estimating equations, demonstrated that current or ex-smoking female first-degree relatives had significantly greater risk of FEV(1) < 80% pred (OR 1.91, 95% CI 1.03- 3.54), FEV(1) < 40% pred (OR 3.56, 95% CI 1.08-11.71), and bronchodilator response greater than 10% of baseline FEV(1) (OR 4.74, 95% CI 1.91-11.75). These results suggest that women may be more susceptible to the development of severe COPD.

Adult↗

Socioeconomic predictors of high allergen levels in homes in the greater Boston area.

In the United States, childhood asthma morbidity and prevalence rates are the highest in less affluent urban minority communities. More than 80% of childhood asthmatics are allergic to one or more inhalant allergens. We evaluated whether socioeconomic status was associated with a differential in the levels and types of indoor home allergens. Dust samples for an ELISA allergen assay were collected from the homes of 499 families as part of a metropolitan Boston, Massachusetts, longitudinal birth cohort study of home allergens and asthma in children with a parental history of asthma or allergy. The proportion of homes with maximum home allergen levels in the highest category was 42% for dust mite allergen (> or = 10 microg/g Der p 1 or Der f 1), 13% for cockroach allergen (> or = 2 U/g Bla g 1 or Bla g 2), 26% for cat allergen (> or = 8 microg/g Fel d 1), and 20% for dog allergen (> or = 10 microg/g Can f 1). Homes in the high-poverty area (> 20% of the population below the poverty level) were more likely to have high cockroach allergen levels than homes in the low-poverty area [51 vs. 3%; OR, 33; 95% confidence interval (CI), 12-90], but less likely to have high levels of dust mite allergen (16 vs. 53%; OR, 0.2; CI, 0.1-0.4). Lower family income, less maternal education, and race/ethnicity (black or Hispanic vs. white) were also associated with a lower risk of high dust mite levels and a greater risk of high cockroach allergen levels. Within a single U.S. metropolitan area we found marked between-community differences in the types of allergens present in the home, but not necessarily in the overall burden of allergen exposure.

Adult↗

Anti-inflammatory therapy reduces total costs of asthma care compared with bronchodilation: the Asthma Outcomes Registry.

BACKGROUND: Current consensus guidelines recommend reliance on anti-inflammatory drugs to treat asthma, reserving theophylline and other long-acting bronchodilators as adjuncts for patients whose symptoms are not well controlled with anti-inflammatory therapy. The effect of such recommendations on total costs of asthma care has not yet been examined, however. OBJECTIVE: To explore the relation between choice of maintenance therapy with anti-inflammatory agents vs long-acting bronchodilators and annual costs of asthma care using data from the Asthma Outcomes Registry. METHODS: Patients 16 years and older were selected from the Asthma Outcomes Registry cohort if they had received either anti-inflammatories (inhaled corticosteroids or cromones) or long-acting bronchodilators (theophylline, salmeterol, oral beta-agonists, or ipratropium bromide), but not both, for at least 1 year before study entry. Oral corticosteroid-dependent patients, those with other chronic lung disease, and those with incomplete cost data during the 365 days before and after their enrollment in the Asthma Outcomes Registry (baseline and follow-up years) were excluded. The effect of anti-inflammatory vs bronchodilator therapy was assessed by comparing the change (follow-up minus baseline) in total costs of asthma care. RESULTS: A total of 314 patients met criteria for study inclusion (237 treated with anti-inflammatories and 77 treated with bronchodilators). Median costs during the baseline year were similar in the anti-inflammatory and bronchodilator groups ($341 and $335, respectively). In the follow-up year, the median change in cost in the anti-inflammatory group was a decline of $93 compared with an increase of $76 in the bronchodilator group (P < .0001). This treatment effect was consistent across subgroups defined by age and amount of medication consumed. CONCLUSIONS: These findings add support to current guidelines recommending reliance on anti-inflammatory therapy to control asthma. The emergence of new therapeutic agents to control inflammation may continue to reduce the costs of treating this important disease.

Adolescent↗

Prospective study of body mass index, weight change, and risk of adult-onset asthma in women.

BACKGROUND: Obesity and asthma are common disorders, and their prevalence rates continue to rise. Although individuals with asthma may gain weight as a result of activity limitations, the relationship between body mass index (BMI), which is calculated as weight in kilograms divided by the square of height in meters, and risk of developing asthma is not known. METHODS: We performed a prospective cohort study of female US registered nurses in the Nurses' Health Study II. In 1991, after excluding women who died with probable asthma or with incomplete data, there were 85911 participants, aged 26 to 46 years. The main outcome measure was self-report of physician-diagnosed asthma with recent use of an asthma medication. RESULTS: From 1991 to 1995, we identified 1596 incident cases of asthma. In a multivariate model controlling for 9 potential confounding factors (including age, race, smoking, physical activity, and energy intake), the relative risks of asthma for 6 increasing categories of BMI in 1991 were 0.9, 1.0 (reference), 1.1, 1.6, 1.7, and 2.7 (P for trend <.001). Stronger associations were found using stricter definitions for asthma, and the finding was present in a variety of subgroups. In analyses controlling for the same variables, as well as BMI at age 18, women who gained weight after age 18 were at significantly increased risk of developing asthma during the 4-year follow-up period (P for trend <.001). CONCLUSIONS: The BMI has a strong, independent, and positive association with risk of adult-onset asthma. The increasing prevalence of obesity in developed nations may help explain concomitant increases in asthma prevalence.

Adult↗

Eosinophilia and positive skin tests predict cardiovascular mortality in a general population sample followed for 30 years.

The authors investigated whether two objective allergy markers, peripheral blood eosinophilia and skin tests for common aeroallergens, were associated with cardiovascular death. Of 5,382 subjects in the Vlagtwedde-Vlaardingen Study (the Netherlands) with data on allergy markers in 1965-1972, 507 subjects died from cardiovascular disease during 30 years of follow-up. Subjects with eosinophilia had an increased risk of cardiovascular death (relative risk (RR) = 1.7; 95% confidence interval (CI): 1.4, 2.2), including ischemic heart disease death (RR = 1.6; 95% CI: 1.2, 2.2) and cerebrovascular death (RR = 2.3; 95% CI: 1.4, 3.8), independent of major risk factors. This association was limited to subjects with a percentage of the predicted forced expiratory volume in 1 second (FEV1 % predicted) of <100%. Positive skin tests were associated with a significantly reduced cardiovascular mortality in subjects with normal lung function and weight who did not smoke (RR = 0.15; 95% CI: 0.05, 0.46). Conversely, when subjects with positive skin tests had a body mass index of > or =25 kg/m2, had an FEV1 % predicted of <80%, or smoked, they had an increased risk for cardiovascular mortality. These results were not restricted to asthmatics. Our data suggest a possible link between eosinophilia and positive skin tests and cardiovascular mortality, especially in combination with other risk factors associated with its mortality.

Asthma↗

Relations between individual and neighborhood-based measures of socioeconomic position and bone lead concentrations among community-exposed men: the Normative Aging Study.

To examine the association between lead exposure and both individual and geographic area indicators of socioeconomic position, the authors measured tibia lead concentration, a biomarker of cumulative lead exposure, using K x-ray fluorescence in a cross-sectional survey of 538 white males aged 50-92 years who were healthy when enrolled in the Normative Aging Study (Boston, Massachusetts) in the 1960s. Data on individual risk factors, education, occupation, and income were collected by questionnaire. Using subjects' residential addresses at the time of the tibia lead measurements, the authors obtained geographic area-specific measures of education, social class, and poverty by linking records to 1990 US Census block group data. In multivariate linear regression analysis controlling for age and cumulative smoking, tibia lead concentrations were 10.39 microg/g (95% confidence interval (CI) 7.80-12.97) higher in men who did not graduate from high school than in men with > or =4 years of college. Among the former men (non-high school graduates), living in an undereducated area was associated with a 9.28 microg/g (95% CI 1.59-16.97) increase in tibia lead level compared with living in a non-undereducated area; among the latter men (college graduates), no difference existed by residential area education (beta = 0.72, 95% CI -5.35 to 6.78). The authors conclude that the influence of individual socioeconomic position on cumulative lead exposure is modified by geographic area conditions.

Adult↗

Race, socioeconomic factors, and area of residence are associated with asthma prevalence.

Asthma prevalence in the United States has been reported to be higher in minority groups such as Blacks and Hispanics. Because a disproportionate number of individuals from such minority groups are of low socioeconomic status (SES), it is unclear how much of the racial/ethnic differences in asthma prevalence is related to low SES. We investigated the effect of SES on the relationship between race/ethnicity and asthma prevalence in a cohort of families with a history of asthma or allergies from the Boston, Massachusetts area. From 499 families, a cohort of 998 parents and 307 children was identified. We used total yearly family income (<$50,000 vs. > or = $50, 000), highest level of education (< or = high school vs. > or = college), and residence in high-poverty areas vs. low-poverty areas as measures of SES. Yearly family income <$50,000, < or = high school education, and residence in high poverty areas were all associated with increased risks for asthma in both cohorts. In the parental cohort, Blacks and Hispanics (OR = 2.1, 95% CI = 1.5, 2.8; and OR = 2.2, 95% CI = 1.5, 3.2, respectively) were at greater risk for asthma than Whites. In the cohort of children, Black and Hispanic children (OR = 2.9, 95% CI = 1.0, 8.0; and OR = 5.3, 95% CI = 1.6, 17.5, respectively) were also at increased risk for asthma. When the three measures of SES were included in the multivariable models, the risks associated with Blacks and Hispanics decreased in both cohorts: OR = 1.4, 95% CI = 0.9, 2.0; and OR = 1.6, 95% CI = 1.0, 2. 6, respectively, for the parents; and OR = 0.8, 95% CI = 0.2, 3.0; and 2.5, 95% CI = 0.5, 11.7, respectively, for the children. We conclude that a large proportion of the racial/ethnic differences in asthma prevalence in our study is explained by factors related to income, area of residence, and level of education.

Adolescent↗

Relationship of blood pressure to cardiovascular death: the effects of pulse pressure in the elderly.

PURPOSE: To investigate the relationship of systolic and diastolic blood pressure to fatal myocardial infarction, fatal stroke and other death related to cardiovascular diseases (CVD). METHODS: The study was based on a prospective longitudinal study conducted by the Veterans Administration at the Boston Outpatient Clinic. Participants are male volunteers from the greater Boston area. Main outcome measures are fatal myocardial infarction, fatal stroke and other deaths related to cardiovascular diseases. The method of pooled logistic regression was used for statistical analysis. RESULTS: For younger men (age 21-59), after adjusting for effects of other risk factors, when systolic and diastolic blood pressure were considered separately, SBP was predictive of cardiovascular death (SBP: RR = 1.23; 95% CI = (1.05, 1.45) per 10 mmHg of increase), and DBP showed a nonsignificant positive trend in relation to cardiovascular death (DBP: RR = 1.27; 95% CI = (0.95, 1.69) per 10 mmHg of increase). For older men (age 60-85), when SBP and DBP were considered separately, SBP (RR = 1.26; 95% CI = (1.02, 1.55) per 15 mmHg of increase) was directly related, but DBP (RR = 1.05; 95% CI = (0.83, 1.32) per 8 mmHg of increase) was not related to cardiovascular death. However, for the elderly group, when SBP and DBP were considered jointly in the regression model, then the regression coefficient of DBP (beta = -0.018, p = 0.30) was of approximately the same absolute magnitude as that of SBP (beta = 0.021, p = 0.02) but opposite in sign. For younger men, when SBP and DBP were considered jointly, SBP (beta = 0.021, p = 0.049) but not DBP (beta = -0.001, p = 0.953) was positively related to cardiovascular death. CONCLUSIONS: We found that, for the elderly, pulse pressure (SBP-DBP) may be a more accurate predictor of cardiovascular death than either SBP or DBP alone. The relative risk per 35 mmHg of increase of pulse pressure, which equals the approximate interval from the 10th to the 90th percentile in the elderly group, is 2.1 with 95% CI = (1.1, 3.8). In younger subjects, SBP, but not DBP, is an independent predictor of fatal CVD.

Adult↗

Gene by environment interaction and asthma.

The term interaction has two specific meanings in epidemiology. The first definition is purely a statistical one. Interaction is defined as the coefficient of the product term of two or more risk factors. An alternative definition is a more biologically oriented one in which interaction between two risk factors is defined as their coparticipation in the same causal mechanism of disease development. There are at least five different types of biological gene by environment interaction. It is important to recognize that clinical or epidemiological studies alone are unable to distinguish between these five different types of biological interaction. Asthma is a prototypical complex trait in which gene by environment interaction is important in disease causation. Environmental factors important in asthma include cigarette smoking (active/passive), allergen exposure, viral and bacterial respiratory illness, occupation, and possibly diet. There are two primary study designs that have been utilized for the assessment of gene by environment interaction: a traditional case control study or a nested case control study or a case control study nested within the larger longitudinal cohort. There are three important methodological issues in the assessment of gene by environment interaction. The first is the issue of misspecification of either genotype or environmental exposure or, for that matter, disease status. The second is possible confounding, and the third is the confounding of interaction with dose response. The four most critical factors for determining sample size for gene by environment interaction studies are the odds ratio for the interaction, the prevalence for exposure in the population, the prevalence of the genotype in the population, and the case to control ratio. In general, sample sizes have been too small to detect meaningful gene by environment interactions.

Animals↗

The relationship of skin test positivity, high serum total IgE levels, and peripheral blood eosinophilia to symptomatic and asymptomatic airway hyperresponsiveness.

The relationships of skin test positivity, high serum total IgE levels (> 100 kU/L), and peripheral blood eosinophilia (>/= 275 cells/microliter) to symptomatic (either chronic cough, chronic phlegm, bronchitis episodes, dyspnea, wheeze, or asthma) and asymptomatic bronchial hyperresponsiveness (BHR) were studied cross-sectionally in 620 adult subjects who participated in the Vlagtwedde-Vlaardingen Study of 1989 and 1990. Eosinophilia (OR = 2.06, 95% CI = 1.28 to 3.31) and skin test positivity (OR = 1.66, 95% CI = 1.02 to 2.71) were both significantly associated with BHR independent of age, sex, smoking, and urban area of residence. High serum total IgE levels were not associated with BHR (OR = 1.29, 95% CI = 0.81 to 2.03). Separate analyses for symptomatic and asymptomatic subjects showed that the higher risk of BHR with skin test positivity applied only to symptomatic subjects (OR = 5.78, 95% CI = 1.63 to 20.51), independent of eosinophilia and high serum total IgE levels. The higher risk of BHR with eosinophilia was not different between symptomatic and asymptomatic subjects, and independent of skin test positivity and high serum total IgE levels. The results of this study show that, in the general adult population, eosinophilia is associated with BHR both in symptomatic and asymptomatic persons, whereas skin test positivity is associated with BHR only in symptomatic subjects.

Adult↗