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Biomedical subjects

B G Ferris

Publications and source records attributed to B G Ferris.

At least 37 records · Page 2Linked to original sources
PubMed1989

Short-term pulmonary function change in association with ozone levels.

As part of the ongoing Harvard Six Cities study of the respiratory effects of air pollution, repeated measurements of pulmonary function (FVC, FEV75, MMEF, and Vmax75) were taken at approximately weekly intervals in a population of 154 school children living in Kingston and Harriman, Tennessee. A series of as many as six measurements were obtained for each child over approximately a 2-month period beginning in February 1981. Concurrent measurements of ambient ozone, and fine particle and fine sulfate concentrations were obtained at a site near the study community. The maximal hourly ozone concentration observed during the study was 78 ppb. Child-specific linear regressions were fit that related short-term pulmonary function changes to air pollution or temperature. We found that decrements in FVC, FEV75, MMEF, and Vmax75 were associated with ozone, but not with particulate levels. Decrements in FVC, MMEF, and Vmax75 were also associated with temperature. Although slopes of pulmonary function on ozone varied across children, in general there was no evidence that this variation represented heterogeneity of response as opposed to random estimation errors. In addition, no evidence was found that individual response to ozone was related to sex, presence of asthma, respiratory illness before 2 yr of age, or the MMEF/FVC ratio, a rough surrogate for airway size. We conclude that ambient exposures to ozone at levels well below the National Ambient Air Quality Standard of 120 ppb are associated with transient decreases in lung function, the long-term significance of which is uncertain.

Air Pollutants↗
PubMed1989

Effects of inhalable particles on respiratory health of children.

Results are presented from a second cross-sectional assessment of the association of air pollution with chronic respiratory health of children participating in the Six Cities Study of Air Pollution and Health. Air pollution measurements collected at quality-controlled monitoring stations included total suspended particulates (TSP), particulate matter less than 15 microns (PM15) and 2.5 microns (PM2.5) aerodynamic diameter, fine fraction aerosol sulfate (FSO4), SO2, O3, and No2. Reported rates of chronic cough, bronchitis, and chest illness during the 1980-1981 school year were positively associated with all measures of particulate pollution (TSP, PM15, PM2.5, and FSO4) and positively but less strongly associated with concentrations of two of the gases (SO2 and NO2). Frequency of earache also tended to be associated with particulate concentrations, but no associations were found with asthma, persistent wheeze, hay fever, or nonrespiratory illness. No associations were found between pollutant concentrations and any of the pulmonary function measures considered (FVC, FEV1, FEV0.75, and MMEF). Children with a history of wheeze or asthma had a much higher prevalence of respiratory symptoms, and there was some evidence that the association between air pollutant concentrations and symptom rates was stronger among children with these markers for hyperreactive airways. These data provide further evidence that rates of respiratory illnesses and symptoms are elevated among children living in cities with high particulate pollution. They also suggest that children with hyperreactive airways may be particularly susceptible to other respiratory symptoms when exposed to these pollutants.(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollutants↗
PubMed1989

Chronic obstructive pulmonary disease mortality in six U.S. cities.

Results are presented from a 9- to 12-yr mortality follow-up of 8,427 white adults in six U.S. cities between 25 and 74 yr of age at enrollment. Survival analyses were performed for all causes on 941 confirmed deaths, and for specific primary causes for the subset of 851 death with death certificates. Relative level of FEV1 compared with predicted was a strong predictor of sex-specific chronic obstructive pulmonary disease (COPD), cardiovascular (CV), and all-cause mortality, even after adjusting for age, respiratory symptoms, and smoking. Even in this relatively large cohort, the total number of respiratory deaths was small, and no trend in COPD mortality could be determined over the period of study.

Adult↗
PubMed1989

Home dampness and respiratory morbidity in children.

This study examined the relationship between measures of home dampness and respiratory illness and symptoms in a cohort of 4,625 eight- to 12-yr-old children living in six U.S. cities. Home dampness was characterized from questionnaire reports of mold or mildew inside the home, water damage to the home, and the occurrence of water on the basement floor. Symptoms of respiratory and other illness were collected by questionnaire. Pulmonary function was measured by spirometry. Signs of home dampness were reported in a large proportion of the homes. In five of the six cities, one or more of the dampness indicators were reported in more than 50% of the homes. The association between measures of home dampness and both respiratory symptoms and other non-chest illness was both strong and consistent. Odds ratios for molds varied from 1.27 to 2.12, and for dampness from 1.23 to 2.16 after adjustment for maternal smoking, age, gender, city of residence, and parental education. The relationship between home dampness and pulmonary function was weak, with an estimated mean reduction of 1.0% in FEF25-75 associated with dampness and 1.6% with molds. We conclude that dampness in the home is common in many areas of the United States and that home dampness is a strong predictor of symptoms of respiratory and other illness symptoms among 8- to 12-yr-old children.

Asthma↗
PubMed1988

Cumulative and reversible effects of lifetime smoking on simple tests of lung function in adults.

Data from a random sample of 8,191 men and women from 6 U.S. cities are used to fit a model describing the effects of cumulative and current cigarette smoking on pulmonary function. The data show that smokers suffer an irreversible loss of FVC and FEV1, which is described by a linear function of their cumulative cigarette smoking as measured in pack-years. For a typical male 173 cm tall, the estimated loss of FEV1 is 7.4 ml for each pack-year smoked. For a typical woman, 161 cm tall, the estimated effect is 4.4 ml per pack-year. Current cigarette smoking adds an acute deficit over and above the cumulative effect of lifetime smoking. For any lifetime pack-years, exsmokers have higher levels of FEV1, 123 ml for a typical man, 107 ml for a typical woman, than do current smokers of a pack per day (p less than 0.001). A man who starts smoking one pack of cigarettes per day at 25 yr of age would at age 60, after 35 pack-years of exposure, have an expected FEV1 equal to that of a man 69.4 yr of age who had never smoked. If he stopped smoking at 60 yr of age, his expected level would increase to that of a 66.5-yr-old never-smoker. This model therefore estimates how much lung function is irreversibly lost by smoking, estimates how much could be regained with cessation of smoking, and predicts the future loss of lung function in both cases.

Adult↗
PubMed1987

Occupational exposures and chronic respiratory symptoms. A population-based study.

Data from a random sample of 8,515 white adults residing in 6 cities in the eastern and midwestern United States were used to examine the relationships between occupational exposures to dust or to gases and fumes and chronic respiratory symptoms; 31% of the population had a history of occupational dust exposure and 30% reported exposure to gas or fumes. After adjusting for smoking habits, age, gender, and city of residence, subjects with either occupational exposure had significantly elevated prevalences of chronic cough, chronic phlegm, persistent wheeze, and breathlessness. The adjusted relative odds of chronic respiratory symptoms for subjects exposed to dust ranged from 1.32 to 1.60. Subjects with gas or fume exposure had relative odds of symptoms between 1.27 and 1.43 when compared with unexposed subjects. Occupational dust exposure was associated with a higher prevalence of chronic obstructive pulmonary disease as defined by an FEV1/FVC ratio of less than 0.6, when comparing exposed and unexposed participants (OR = 1.53, 95% Cl = 1.17-2.08). Gas or fume exposure was associated with a small, but not significant, increase in COPD prevalence. Significant trends were noted for wheeze and phlegm with increasing duration of dust exposure. Although 36% of exposed subjects reported exposure to both dust and fumes, there was no evidence of a multiplicative interaction between the effects of the individual exposures. Smoking was a significant independent predictor of symptoms, but did not appear to modify the effect of dust or fumes on symptom reporting. These data, obtained in random samples of general populations, demonstrate that chronic respiratory symptoms and disease can be independently associated with occupational exposures.

Adult↗
PubMed1987

The association between health status and the performance of excessively variable spirometry tests in a population-based study in six U.S. cities.

The relationship between 6 chronic respiratory symptoms and the performance of an excessively variable FEV1 (test failure) was examined among 8,522 white adults in 6 U.S. cities. A total of 747 (8.9%) performed an excessively variable FEV1 according to the American Thoracic Society criterion. After adjusting for smoking, age, and city of residence in 6 separate logistic regression models, the odds ratios for FEV1 failure among men were 2.32, 1.39, 1.40, 1.82, 2.61, 1.92 for moderate breathlessness, chronic cough, phlegm, wheeze, asthma, and recurrent chest illness, respectively. Among women, FEV1 failure was significantly associated with moderate breathlessness, chronic phlegm, wheeze, and asthma with odds ratios of 1.55, 1.45, 1.62, and 1.95, respectively. When all symptoms were evaluated simultaneously in a single logistic regression model, only breathlessness and asthma remained associated with FEV1 failure; odds ratio = 1.97 for asthma and 2.03 for breathlessness among men and 1.53 for both asthma and breathlessness among women. The 11-yr mortality experience of subjects with test failure, as defined by 2 different criteria, was compared to that of the quartile of the cohort with the highest cross-sectional test results. After adjusting for age, gender, and smoking, the relative risks of mortality were 1.62 and 1.98 for subjects with an FEV1 failure as defined by the ATS and 6-Cities criteria, respectively, and 1.99 and 1.90 for the groups with FVC failure as defined by the 2 criteria. Thus test failure is almost as strong a predictor of mortality as poor FEV1.

Adult↗
PubMed1986

Indoor air pollution and pulmonary function growth in preadolescent children.

Results are reported from a study of the association between exposure to sidestream cigarette smoke or gas stove emissions and pulmonary function level and growth rate of 7,834 children seen at 2-5 annual visits between the ages of 6-10 years. Children whose mothers smoked one pack of cigarettes per day had levels of forced expiratory volume in one second (FEV1) at age eight that were 0.81% lower than children of nonsmoking mothers (p less than 0.0001), and FEV1 growth rates approximately 0.17% per year lower (p = 0.05). For a child of age eight with an FEV1 of 1.62 liters, this corresponds to a deficit in rate of change of FEV1 of approximately 3 ml/annum and a deficit of 13 ml at age eight. Children whose mothers smoked one pack per day had levels of forced vital capacity (FVC) at age eight that were 0.33% higher than children of nonsmokers (p = 0.12); however, their growth rates of FVC were 0.17% per year lower (p = 0.04). Because few mothers changed their smoking habits during the course of the study, it was not possible to determine whether the difference in rate of growth was due to current exposure or to an effect of prenatal and early childhood exposure on the course of development. The magnitude of the effect on FEV1 is consistent with deficits in FEV1 of up to 3% in early adult life due to childhood exposure to sidestream cigarette smoke. The importance of this relatively small effect will be evaluated further through follow-up of these children as they are exposed to other risk factors such as personal active smoking. The data provide some evidence for an association between gas stove exposure and pulmonary function level, especially at younger ages, but no evidence for an effect of gas stove exposure on growth rate.

Air Pollutants↗
PubMed1986

Effects of ambient sulfur oxides and suspended particles on respiratory health of preadolescent children.

Reported here are the results from an ongoing study of outdoor air pollution and respiratory health of children living in six cities in the eastern and midwestern United States. The study enrolled 10,106 white preadolescent children between 1974 and 1977 in 3 successive annual visits to each city. Each child received a spirometric examination, and a parent completed a standard questionnaire. Of this cohort, 8,380 children were seen for a second examination 1 yr later. An air pollution monitoring program was begun in each community at about the time of the first examination. For this report, measurements of total suspended particulates (TSP), the sulfate fraction of TSP (TSO4), and sulfur dioxide (SO2) concentrations at study-affiliated outdoor stations were combined with measurements at other public and private monitoring sites to create a record of TSP, TSO4, and SO2 concentrations in each of 9 air pollution regions during the 1-yr period preceding each examination and, for TSP, during each child's lifetime up to the time of testing. Across the 6 cities, frequency of cough was significantly associated with the average of 24-h mean concentrations of all 3 air pollutants during the year preceding the health examination (p less than 0.01). Rates of bronchitis and a composite measure of lower respiratory illness were significantly associated with average particulate concentrations (p less than 0.05). In analyses restricted to lifetime residents, these outcomes were significantly associated with measures of lifetime mean TSP concentration. Within the cities, however, temporal and spatial variation in air pollutant concentrations and illness and symptom rates were not positively associated.(ABSTRACT TRUNCATED AT 250 WORDS)

Air Pollutants↗
PubMed1985

Distribution of forced expiratory volume in one second and forced vital capacity in healthy, white, adult never-smokers in six U.S. cities.

As part of a longitudinal study of the respiratory health effects of air pollution, we measured the lung function of 2,454 white adults 25 to 74 yr of age who had never smoked and who reported no respiratory symptoms. These measurements were analyzed to develop a simple model for the cross-sectional dependence of pulmonary function on height, sex, and age. Both forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) can be effectively standardized for body size by dividing each pulmonary function measurement by the square of the standing height (HT2). The age-specific distribution of these standardized measurements is approximately Gaussian, with variance that is independent of age. Plots of FEV1/HT2 and FVC/HT2 against age showed a nonlinear relationship consistent with an increase in the rate of pulmonary function loss with age. On the basis of these graphic analyses, both pulmonary function measurements were fitted to a four-parameter normative model including sex and linear and quadratic terms in age as dependent variables. This model gave predictions that were very close to those from more complicated models currently in use. Predicted percentile levels were calculated for each sex and age, and shown to describe the observations well. The estimated annual change in height-standardized lung function based on the cross-sectional model was compared with the observed change between the first and second examinations of these adults 3 yr later. The observed changes were close to predicted values, except for subjects younger than 35 yr of age at their first examination. The observed change was larger for men than for women. Such simple longitudinal comparisons are subject to selection bias. In this study, subjects in the lowest quartile of FEV1/HT2 for their age and sex at the first examination had a lower probability of providing a lung function measurement 3 yr later.

Adult↗
PubMed1985

Potential human health effects of acid rain: report of a workshop.

This report summarizes the potential impact of the acid precipitation phenomenon on human health. There are two major components to this phenomenon: the predepositional phase, during which there is direct human exposure to acidic substances from ambient air, and the post-depositional phase, in which the deposition of acid materials on water and soil results in the mobilization, transport, and even chemical transformation of toxic metals. Acidification increases bioconversion of mercury to methylmercury, which accumulates in fish, increasing the risk to toxicity in people who eat fish. Increase in water and soil content of lead and cadmium increases human exposure to these metals which become additive to other sources presently under regulatory control. The potential adverse health effects of increased human exposure to aluminum is not known at the present time.

Acids↗
PubMed1985

Effects of passive smoking on health of children.

Analysis of data on the effects of passive smoking obtained in preadolescent children from the Harvard Six-Cities Study demonstrates an exposure-response relationship between the number of smokers in the household and the reporting rates for doctor-diagnosed respiratory illness before age 2, history of bronchitis, wheeze most days and nights apart from colds, and a composite of symptoms defined as the lower respiratory index. Similarly, when only the amount currently smoked by the mother was used, the data indicated a relatively uniform increase in each of the reported diseases and symptoms. FEV1 was lower in children with smoking mothers compared to children of nonsmoking mothers. Rate of increases in FEV1 after adjusting for normal growth was significantly smaller in children of smoking mothers and was related also to amount smoked. Notably the effect on level of FVC was not seen and this finding, consistent in several studies, remains unexplained. Although children of smoking mothers were shorter on the average than children of nonsmoking mothers, no on-going passive smoking effect on height growth can be ascertained. All these differences are small and their medical significance remains to be defined.

Body Height↗
PubMed1985

Problems in the estimation of human exposure to components of acid precipitation precursors.

Problems associated with estimation of human exposure to ambient air pollutants are discussed. Ideally, we would prefer to have some indication of actual dose. For most pollutants this is not presently feasible. Specific problems discussed are adequacy of outdoor monitors; the need to correct for exposures and time spent indoors; the need to have particle size distributions described and the chemistry of the particles presented. These indicate the need to develop lightweight accurate and reliable personal monitors.

Acids↗
PubMed1985

Harvard Air Pollution Health Study in six cites in the U.S.A.

The Harvard Air Pollution Health Study has been a ten year prospective study of respiratory symptoms and pulmonary function of children and adults living in six U.S. communities. Indices of acute and chronic effects of air pollution exposures have been studied. Evidence is presented for adverse effects of ambient and indoor air pollution on children. Relationships between ambient TSP concentrations and hospital emergency room admissions, temporary decreases in pulmonary functions and prevalence of community bronchitis all indicate a slight adverse effect. Refinements of these relationships will occur when fine fraction and acid sulfate aerosol concentrations are incorporated into the health analysis. Exposures to cigarette smoke at home are associated with increased reported respiratory symptoms in children. There is a negative relationship between maternal smoking and age and sex adjusted height for children. Results from indoor and personal exposure studies have lead to the design of an acute symptoms and indoor air pollution study. Between 1985 and 1988 1800 children will be tracked for a year while respirable particles, nitrogen dioxide, water vapor and air exchange will be measured in their homes. Using continuous sulfate/sulfuric acid monitors built at Harvard, we are characterizing the magnitude, duration and frequency of acid aerosol events in each of our study cities. This information will be utilized in the analysis of the respiratory symptom data. The Harvard Air Pollution Health Study is providing information on the relationship among health variables and air pollutant exposures. In addition, this study will add to our understanding of lung growth and aging and the risk factors associated with chronic respiratory disabilities.

Adult↗
PubMed1984

Passive smoking and height growth of preadolescent children.

The attained height and height growth rate of 9273 children participating in a longitudinal study of the health effects of air pollutants were analysed to assess the association between passive exposure to cigarette smoke and physical growth between 6 and 11 years of age. Children were measured annually for 2 to 6 years. Each height measurement was adjusted for sex and age by the NCHS anthropometric standards. Each child's adjusted heights were then re-expressed as level of attained height and growth rate. Attained height exhibited a dose-response relationship with amount of current maternal cigarette smoking (p less than 0.001). Children whose mothers smoked ten or more cigarettes daily were approximately 0.65 cm shorter than children of non-smokers, while children whose mothers smoked between 1 and 9 cigarettes per day were 0.45 cm shorter. However, passive smoking was not correlated with the child's growth rate. Exposure to paternal smoking was not significantly associated with height, either in terms of attained level or growth rate. These results indicate that passive smoking in the 6- to 11-year-old child does not continue to affect the growth rate of height and that the observed association between attained height and maternal smoking behaviour is due to exposures in utero and/or during infancy and the preschool years.

Body Height↗
PubMed1984

Passive smoking, gas cooking, and respiratory health of children living in six cities.

As part of a longitudinal study of the respiratory health effects of indoor and outdoor air pollutants, pulmonary function, respiratory illness history, and symptom history were recorded at 2 successive annual examinations of 10,106 white children living in 6 cities in the United States. Parental education, illness history, and smoking habits also were recorded, along with the fuel used for cooking in the child's home. Maternal cigarette smoking was associated with increases of 20 to 35% in the rates of 8 respiratory illnesses and symptoms investigated, and paternal smoking was associated with smaller but still substantial increases. Illness and symptom rates were linearly related to the number of cigarettes smoked by the child's mother. Illness rates were higher for children of current smokers than for children of ex-smokers. The associations between maternal smoking status and childhood respiratory illnesses and symptoms were reduced but not eliminated by adjustment for parental illness history. Levels of forced expiratory volume in one second (FEV1) were significantly lower for children of current smokers than for children of nonsmokers at both examinations and highest for children of ex-smokers. Levels of forced vital capacity (FVC) were lower for children of nonsmokers than for children of current smokers at both examinations, but the difference was statistically significant only at the first examination. Both the increase in mean FVC and the decrease in mean FEV1 among children of current smokers were linearly related to daily cigarette consumption. None of the respiratory illnesses and symptoms studied was significantly associated with exposure to gas cooking in the child's home.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗