Search

Background Some patients with COPD report frequent acute exacerbations (AECOPD) of the disease (FE), whereas others suffer them infrequently (IE). Because the current diagnosis of exacerbation relies on patient9s perception of increased symptoms (mostly dyspnoea), we hypothesised that dyspnoea perception might be different in COPD patients with FE (≥2 exacerbations or 1 hospitalisation due to AECOPD in the previous year) or IE (≤1 exacerbation in the previous year), AECOPD being defined by the institution antibiotics and/or steroids treatment, or hospital admission. Objective To test the hypothesis that dyspnoea perception is increased in FE and/or decreased in IE with COPD. Methods We compared the perception of dyspnoea (Borg scale), mouth occlusion pressure 0.1 s after the onset of inspiration (P 0.1 ) and ventilatory response to hypercapnia (ΔV E /ΔP ET CO 2 ) in 34 clinically stable COPD patients with FE (n=14) or IE (n=20), with similar age, gender, body mass index and degree of airflow limitation. As a reference, we studied a group of age-matched healthy volunteers (n=10) with normal spirometry. Results At rest, P 0.1 was higher in FE than IE and controls (p Conclusions Dyspnoea perception during CO 2 rebreathing is enhanced in FE and blunted in IE. These differences may contribute to the differential rate of reported exacerbations in FE and IE. Trial registration number NCT02113839.

Background: Women employed in domestic cleaning are at increased risk for symptoms of obstructive lung disease, but the agents responsible are unknown. Aims: To investigate common tasks and products in occupational domestic cleaning in relation to respiratory morbidity. Methods: Case-control study in domestic cleaning women nested within a large population based survey of women aged 30–65 years; 160 domestic cleaning women with asthma symptoms, chronic bronchitis symptoms, or both and 386 without a history of respiratory symptoms were identified. Detailed exposures were evaluated for 40 cases who reported still having symptoms at the recruitment interview, and 155 controls who reported not having symptoms. All tasks performed and products used when cleaning houses were determined in a face-to-face interview. Lung function, methacholine challenge, and serum IgE testing were performed. Personal exposure measurements of airborne chlorine and ammonia were performed in a subsample. Associations between asthma, chronic bronchitis, and cleaning exposures were evaluated using multiple logistic regression analysis. Results: Airborne chlorine (median level 0–0.4 ppm) and ammonia (0.6–6.4 ppm) were detectable during occupational domestic cleaning activities. Cases used bleach more frequently than controls; adjusted odds ratio (OR) for intermediate exposure was 3.3 (95% CI 0.9 to 11) and for high exposure 4.9 (1.5 to 15). Other independent associations included accidental inhalation of vapours and gases from cleaning agents and washing dishes. These associations were more pronounced for cases with asthma symptoms than for those with symptoms of chronic bronchitis, but were not related to sensitisation to common allergens. Conclusions: Asthma symptoms in domestic cleaning women are associated with exposure to bleach and possibly other irritant agents. The public health impact of the use of irritant cleaning products could be widespread since the use of these products is common both in the workplace and at home.

Objectives Cleaning workers are at elevated risk of asthma. Many products used in this sector are also widely used in private homes. We studied the relationships between asthma symptoms and the use of specific cleaning products at work and at home. Methods Forty-two cases (mean age 42 y) with asthma symptoms and 53 controls (age 48 y) without a history of asthma or lower respiratory tract symptoms participated in a case-control study nested within a cohort of cleaning workers. Information on the use of cleaning products at work and at home in the last year was obtained in face-to-face interviews. Associations between asthma and the use of specific cleaning products at work were evaluated using logistic regression analyses adjusted for age, sex, smoking status and domestic use. Results Hypochlorite bleach (91%), soaps (61%) and acidic scale removers (45%) were the most frequently used products at work. Use of ammonia and multi-use cleaners at work was reported more often among cases than controls; OR 2.7 (95% CI 0.9 to 8.3) and 2.3 (0.7 to 6.9), respectively. The risks increased with the duration of use (p-trend for multi-use 0.05). The highest risks were found when products were used both at work and at home (multi-use cleaners OR 4.8; 1.3 to 18, ammonia OR 3.2; 0.7 to 15). Conclusions Exposure to irritant cleaning products at work and at home is associated with asthma symptoms. These results support the hypothesis that asthma in cleaning workers is predominantly irritant-induced.

The association of pulmonary fibrosis and primary biliary cirrhosis (PBC) remains controversial. To determine the frequency of pulmonary fibrosis in PBC, a carefully selected series of 14 PBC patients, seven patients with Sicca complex, and 14 control subjects have been studied. Seven of the 14 patients with PBC had Sjögren's syndrome, four of whom had some clinical evidence of pulmonary disease. Evaluation of ventilatory capacity, gas transfer factor, arterial blood gases, and lung mechanics were performed. Gas transfer was reduced in patients with PBC associated with Sjögen's syndrome and in patients with the Sicca complex. These results suggest that the respiratory, clinical, ad functional abnormalities found in PBC are related to the presence of an associated Sjögen's syndrome.