Impaired Respiratory Health Research Articles

Does respiratory health contribute to the effects of long-term air pollution exposure on cardiovascular mortality?

BackgroundThere is growing epidemiological evidence that short-term and long-term exposure to high levels of air pollution may increase cardiovascular morbidity and mortality. In addition, epidemiological studies have shown an association between air pollution exposure and respiratory health. To what extent the association between cardiovascular mortality and air pollution is driven by the impact of air pollution on respiratory health is unknown. The aim of this study was to investigate whether respiratory health at baseline contributes to the effects of long-term exposure to high levels of air pollution on cardiovascular mortality in a cohort of elderly women.MethodWe analyzed data from 4750 women, aged 55 at the baseline investigation in the years 1985–1994. 2593 of these women had their lung function tested by spirometry. Respiratory diseases and symptoms were asked by questionnaire. Ambient air pollution exposure was assessed by the concentrations of NO2 and total suspended particles at fixed monitoring sites and by the distance of residency to a major road. A mortality follow-up of these women was conducted between 2001 and 2003. For the statistical analysis, Cox' regression was used.ResultsWomen with impaired lung function or pre-existing respiratory diseases had a higher risk of dying from cardiovascular causes. The impact of impaired lung function declined over time. The risk ratio (RR) of women with forced expiratory volume in one second (FEV1) of less than 80% predicted to die from cardiovascular causes was RR = 3.79 (95%CI: 1.64–8.74) at 5 years survival time and RR = 1.35 (95%CI: 0.66–2.77) at 12 years. The association between air pollution levels and cardiovascular death rate was strong and statistically significant. However, this association did only change marginally when including indicators of respiratory health into the regression analysis. Furthermore, no interaction between air pollution and respiratory health on cardiovascular mortality indicating a higher risk of those with impaired respiratory health could be detected.ConclusionRespiratory health is a predictor for cardiovascular mortality. In women followed about 15 years after the baseline investigation at age 55 years long-term air pollution exposure and impaired respiratory health were independently associated with increased cardiovascular mortality.

Socio-economic status is related to incidence of asthma and respiratory symptoms in adults

The aim of the present study was to assess the association between socio-economic status and impaired respiratory health in a 10-yr follow-up of a population-based postal survey in Northern Sweden. Multiple logistic regression was used to estimate odds ratios in relation to socio-economic class, using age, sex, a family history of asthma, smoking habits, and occupational exposures to dust, gases and fumes as possible confounders. The study comprised 2,341 males and 2,413 females. Cumulative incidences were generally lowest in professionals, including executives and civil servants at intermediate and higher levels, who were chosen as reference group. Manual workers in industry showed a significantly increased risk of developing asthma, recurrent wheeze, attacks of shortness of breath or a combination of the two, and chronic productive cough. Manual workers in service showed a similar pattern for attacks of shortness of breath, recurrent wheeze, or a combination of the two, and chronic productive cough. The corresponding population attributable risks were approximately 10%. Low socio-economic status was a risk factor for the development of asthma, symptoms common in asthma and chronic productive cough.

Biomarkers and chemosensory irritations.

A literature review on studies in humans, applying physiological methods to monitor environmentally induced reactions in eyes and upper respiratory tract. The focus was on chemical exposures, but other occupational factors and indoor exposures were included. Original articles were gathered from Medline until November 2000, combined with peer-reviewed publications from other sources. Ocular methods included measurement of tear film break-up time (BUT), blink frequency, detection of corneal damage, by vital staining, and cells or inflammatory markers in tear fluid. Nasal methods included acoustic rhinometry, rhinostereometry, and nasal peak expiratory flow. In addition, nasal lavage with isotonic sodium chloride solution was applied to measure concentrations of leucocytes, or biomarkers of secretion or inflammation in nasal lavage fluid (NAL). Most occupational studies were on nasal effects of organic or inorganic dust. There were few studies on occupational exposure to organic solvents or chemical irritants. Some studies demonstrated associations between ocular and nasal physiological response and the indoor environment. Finally, there were some exposure-chamber studies on effects of specific volatile organic compounds (VOCs). Little is known about adaptation at repeated ocular or nasal exposure to irritants. Physiological measurements can be valuable complements to symptom registration, but there is a need for standardised investigations. There is a lack of studies on ocular and nasal physiological responses in relation to specific chemical compounds. Experimental studies, with repeated exposure and longer follow-up time on biomarkers, are needed. Finally, there is a need for longitudinal epidemiological studies to elucidate if observed effects should be interpreted as variation within normal physiology, or as early signs of impaired ocular and respiratory health.

Home dampness and respiratory health status in european children.

Living in a damp home has been associated with impaired respiratory health in previous studies, but objective data on lung function variability and atopy have been lacking from most studies. Data collected in the winter of 1993-1994 in the framework of the PEACE study (Pollution Effects on Asthmatic Children in Europe) were used to study the association between home dampness and Peak Flow (PEF) variability, frequency of respiratory symptoms and relief medication use during the period of observation. Children were selected with a screening questionnaire on the basis of positive answers to questions on symptoms of asthma and chronic cough. Children were instructed to perform PEF measurements with Miniwright PEF meters twice daily over a period of 2 months. Parents kept diaries on respiratory symptoms and medication use of their children. Data on demographic and housing characteristics were derived from a parent-administered questionnaire. As indicators for home dampness reported moisture stains and moulds were used. Children were tested for atopy with skin-prick tests. Data from 1614 children from 13 centres in 10 different countries were available for analysis. Linear regression models and prevalence rate ratios were used to investigate the association between home dampness and PEF variability and the period prevalence of cough, phlegm, lower and upper respiratory symptoms and bronchodilator use. In atopic children, PEF variability was positively related to self-reported moulds but not to moisture stains. The period prevalence of cough and upper respiratory symptoms was significantly higher in children living in houses with reported moulds, compared with 'dry' homes. These results show that self-reported moulds in homes are associated with objective as well as subjective markers of airway lability in European children with chronic respiratory symptoms.

Spirometric Lung Function: Distribution and Determinants of Test Failure in a Young Adult Population

Spirometric test failure has been defined as failure by a subject to meet the acceptability and/or reproducibility criteria laid down by the American Thoracic Society for measurements derived from forced expiratory maneuvers. The prevalence and determinants of spirometric test failure were examined in 416 men and women aged 20 to 45 yr working in an office environment. In this study population, 11.5% (28 men and 20 women) exhibited test failure for forced expiratory volume in one second (FEV1). The main determinant of test failure in men was bronchial hyperresponsiveness to methacholine challenge (odds ratio 6.7; confidence interval 1.7, 27.1) and in women being a current smoker (odds ratio 4.02; confidence interval 1.13, 14.33). There was also a relationship to eczema in both men and women, but not at a statistically significant level. When FEV1 variability was defined as the difference (in milliliters) between the two best FEV1 values and the results of men and women combined for analysis, significant predictors were a history of eczema, recurrent chest illness in the past 3 yr, and level of bronchial responsiveness to inhaled methacholine. These findings contribute to the gathering evidence that test failure may be of itself an indicator of impaired respiratory health, and its association with bronchial hyperresponsiveness to methacholine in men suggests that in them test failure is related to airway lability, but in women the relationship to smoking suggests an irritative mechanism.