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L R Maunder

Publications and source records attributed to L R Maunder.

14 recordsLinked to original sources
PubMed1989

Smoking and cotton dust effects in cotton textile workers.

Cotton textile workers have an increased prevalence of both obstructive and restrictive lung function patterns compared with control subjects. Similar abnormal patterns may occur with respiratory diseases of other etiologies, notably those associated with cigarette smoking. The shape of the maximum expiratory flow volume (MEFV) curve has been used to characterize patterns of lung function abnormality. To better evaluate the respiratory effects of cotton dust exposure and to contrast them with those of cigarette smoking, we defined a new functional parameter (angle beta) related to the shape of the MEFV curve. We compared 477 cotton textile workers, both current smokers and never smokers, 45 years and older, with 932 similarly aged control subjects from three communities. Smokers, regardless of their occupational exposure or sex, have smaller beta values than nonsmokers. Cotton textile workers, despite a greater prevalence of abnormal lung function, have beta values that do not differ from those of persons without occupational exposure to cotton dust. We suggest that morphologic patterns of flow volume curves reflect separate effects of cotton dust exposure and smoking and may be related to different sites of airway injury.

Aged↗
PubMed1988

The shape of the maximum expiratory flow volume curve.

Differences in the shape of the maximum expiratory flow volume (MEFV) curve have been associated with pathologic states and physiologic differences between normal individuals. We describe variations in a new parameter, angle beta, which characterizes the general configuration of the MEFV curve among healthy subjects and subjects with disease in 5,140 white individuals. Women had consistently larger beta angles than men. There was a progressive decline in beta with advancing age. Cigarette smokers had lower beta angles than did lifetime never-smokers. Subjects with abnormal lung function patterns had lower beta angles than individuals with a normal pattern. Finally, individuals with asthma, chronic bronchitis, dyspnea and wheezing had significantly lower beta angles than healthy individuals. Further clinical and epidemiologic studies are needed to evaluate this measurement's possible value in pulmonary function evaluation.

Adolescent↗
PubMed1986

Smoking and cotton dust effects in cotton textile workers: an analysis of the shape of the maximum expiratory flow volume curve.

Cotton textile workers have an increased prevalence of both obstructive and restrictive lung function patterns when compared to control subjects. Similar abnormal lung function patterns may occur with other respiratory diseases, notably those associated with cigarette smoking. The shape of the maximum expiratory flow volume (MEFV) curve has been used to characterize patterns of lung function abnormality. We defined a new functional parameter (angle beta) related to the shape of the MEFV curve in order better to characterize the respiratory effects of cotton dust exposure. In this study, 477 cotton textile workers, both current smokers and never smokers 45 years and older, were compared to 932 similarly aged control subjects from three communities: Lebanon and Ansonia, CT, and Winnsboro, SC. Smokers, regardless of their occupational exposure of sex, have smaller values of beta than do nonsmokers. Cotton textile workers who have more abnormal lung function than do controls, cannot be distinguished from controls by beta. We suggest that such functional differences between cotton and smoking effects may reflect injury to different portions of the bronchial tree.

Aged↗
PubMed1984

Cotton dust and smoking effects on lung function in cotton textile workers.

Both smoking and exposure to cotton textile dust have been associated with the development of chronic obstructive lung disease. The relative importance of these two effects are examined in this paper. This investigation is based on a cross-sectional study of white active and retire cotton textile workers 45 years and older seen in 1973 in Columbia, South Carolina with an average of 35 years worked in the mills. A questionnaire was completed and an expiratory flow volume curve obtained for each worker studied. Standard pulmonary function parameters including the forced vital capacity (FVC), the forced expired volume in one second (FEV1), and the maximum expiratory flow at 50% (MEF50%), and at 25% (MEF25%) were recorded. White residents 45 years and older from three communities studied from 1972 to 1974 were used as controls. A two-way analysis of variance examined both the effects of cotton dust and smoking on lung function. Both exposures significantly influenced lung function and were found to be additive and often equally important. When one effect was more important than the other, it was in FVC and FEV1 for cotton dust and in MEF50% and MEF25% for smoking.

Dust↗
PubMed1984

The relationship of respiratory symptoms and lung function loss in cotton textile workers.

We explored the relationship between a number of respiratory symptoms or symptom complexes (e.g., cough, recent wheeze, byssinosis) and lung function in white cotton textile workers (CTW) and control subjects 45 yr of age or older. The CTW were studied in 1973 and in 1979 in Columbia, South Carolina, and the control subjects were studied in 1972 and in 1978 in Lebanon, Connecticut. The CTW had a high prevalence of byssinosis (18%) and other symptoms. For each symptom or symptom complex, among persons with the symptom, CTW had lower lung function on the average than did control subjects. Also, among persons without the particular symptom, CTW had lower lung function than did control subjects. This pattern also occurred for persons without any respiratory symptoms (i.e., asymptomatic). Moreover, persons (CTW or control subjects separately) reporting the presence of a particular symptom had, in general, lower lung function than did those without the symptom. Among nonsmokers, all these same patterns usually held, but differences were often not statistically significant because of the small numbers of persons with symptoms. We conclude that on a group basis, respiratory function is more impaired in CTW than in control subjects with respiratory symptoms, that respiratory function is more impaired in persons (CTW or control subjects) with symptoms than in those without, and that even asymptomatic CTW have significantly greater lung function impairment than do control subjects.

Aged↗
PubMed1984

The pattern of lung function abnormalities in cotton textile workers.

Reversible airway obstruction has been shown to be a characteristic finding of early byssinosis. In the chronic phase of this disease, the patterns of respiratory abnormalities have not been well defined. We examined the lung function of a cohort of 383 older (45 yr of age or more), active and retired, cotton textile workers seen both in 1973 and in 1979 in Columbia, South Carolina. A group of control subjects consisted of 277 white community residents of comparable age from Lebanon, Connecticut. Using data at follow-up, 25% of the male and 14% of the female cotton textile workers had moderate to severe obstructive airway abnormalities, as opposed to 13 and 5% for male and female control subjects (p less than 0.01). There were fewer persons with restrictive than with obstructive lung patterns among cotton textile workers and control subjects, but again, abnormalities were more prevalent among cotton textile workers. Overall, 50% of male cotton textile workers and 37% of female cotton textile workers had some abnormality of lung function, as opposed to 29% of male and 20% of female control subjects (p less than 0.001). More abnormalities were present in cotton textile workers than in control subjects when only lifetime nonsmokers were examined. We conclude that there is an increased prevalence of both obstructive and restrictive lung function abnormalities among cotton textile workers when compared with control subjects, with the most common pattern being obstructive.

Age Factors↗
PubMed1982

A prospective study of chronic lung disease in cotton textile workers.

A cohort of both active and retired older cotton textile workers was examined prospectively over a 6-year period to establish the nature and extent of chronic lung disease. Respiratory symptoms and lung function were studied in these workers and in a group of similarly aged controls. The cotton textile workers had higher prevalence and attack rates of respiratory symptoms than did controls even with smoking habits taken into account. Chronic bronchitis developed in 16% of all cotton textile workers compared to 1% of controls over the follow-up period (p less than 0.001). The cotton workers suffered a larger loss of lung function over 6 years than did controls. Male workers lost 42 mL/yr of forced expiratory volume in 1 second, although male controls lost only 25 mL/yr (p = 0.001). Similar differences were seen in women, and in both men and women who were nonsmokers. Retired cotton textile workers had more symptoms and disability than active workers. We conclude that chronic lung disease is not only irreversible but may progress even after exposure to cotton dust has ended.

Byssinosis↗
PubMedDate not supplied

The Framingham eye study: introduction to the monograph.

This article briefly summarizes the monography, The Framingham Eye Study Monograph: an Ophthalmological and Epidemiological Study of Cataract, Glaucoma, Diabetic Retinopathy, Macular Degeneration, and Visual Acuity in a General Population of 2631 Adults, 1973-1975. This 275-page monograph, authored by H. Liebowitz, D. Krueger, C. Maunder et al, has recently been published by Survey of Ophthalmology (Surv Ophthalmol 24 (suppl):335-610, 1980). The purpose of the study, undertaken by the National Eye Institute, was to provide a description of the prevalence and severity of four diseases that are believed to be the major causes of severe visual handicap among adults in the United States. The monography presents the detailed protocols and record forms, definitions of the specific abnormalities and characteristics, criteria for suspicion and diagnosis of disease, detailed tables of the basic data, evaluation of quality of the data, and discussion of selected findings.

Adult↗
PubMedDate not supplied

The Framingham Eye Study monograph: An ophthalmological and epidemiological study of cataract, glaucoma, diabetic retinopathy, macular degeneration, and visual acuity in a general population of 2631 adults, 1973-1975.

Ophthalmologic examinations for cataract, glaucoma, diabetic retinopathy, macular degeneration and visual acuity were performed on 2631 of the 3977 members of the Framingham (Massachusetts) Heart Study population still living in 1973-1975. The subjects ranged in age from 52 to 85 years. This monograph presents the detailed protocols and record forms for screening and diagnostic examinations, definitions of the specific abnormalities and characteristics used to screen for each disease, criteria for suspicion and diagnosis of diseases, detailed tables of the basic data from the study, evaluation of quality of the data, and discussion of selected findings. The tables provide data on the number and proportion of persons and of eyes with each type of abnormality and each disease, by age and sex. Where appropriate, the data are further classified by location of abnormality, severity, bilaterality and associated visual acuity limitation. The study was sponsored by the National Eye Institute.

Adult↗