Figures
- Fig. 1—
Positive Oasys (occupational asthma system) graphs for the analysis of: a, c) work (▒) and leisure (□) days (case No. 2 (table 4⇓); Oasys overall score 3); and b, d) days with (▒) and without (□) exposure to bleach/degreasers (case No. 1 (table 4⇓); Oasys overall score 2.67). a, b) Diurnal variation (Var) from predicted peak expiratory flow (PEF) and c, d) corresponding PEF record. –––: mean daily PEF; - - - -: maximum/minimum daily PEF; · · ·: 20% diurnal variation (proportion of time spent above this value is helpful in the diagnosis of asthma). Horizontal bars show Oasys scores for complexes.
Tables
- Table 1—
Descriptive characteristics of the study population and those who did not complete the diary
Participants# Nonresponders p-value¶ Subjects 43 (100) 29 (100) Age yrs 49 (34–65) 53 (31–66) 0.14 Smoking status Never-smoker 27 (63) 23 (79) Ex-smoker 6 (14) 0 (0) 0.09 Current smoker 10 (23) 6 (21) Symptoms reported in survey Asthma+ only 11 (26) 13 (45) Chronic bronchitis§ only 21 (49) 11 (38) 0.23 Asthma+ and chronic bronchitis§ 11 (26) 5 (17) Symptoms reported in diaryƒ Upper respiratory tract 24 (56) NA Lower respiratory tract 16 (37) NA FEV1 % pred##,¶¶ 96 (68–127) 101 (77–123) 0.08 Mean PEF per person L·min-1 395 (212–525) NA PEF % pred## 113 (61–136) NA Bronchial hyperresponsiveness++,§§ 8 (31) 1 (6) 0.05 Atopyƒƒ,### 7 (18) 3 (11) 0.44 Houses currently employed in n 2 (1–7) 2 (1–4) 0.53 Weekly domestic cleaning work h 16 (3–52) 18 (3–48) 0.99 Domestic cleaning employment yrs 17 (2–53) 22 (2–56) 0.05 Data are presented as median (range) or n (%). FEV1: forced expiratory volume in one second; % pred: percentage of the predicted value; PEF: peak expiratory flow. NA: information not available. #: not including the eight females excluded from analyses (see Analyses section); ¶: Mann-–Whitney test (continuous variables) or Chi-squared test (categorical variables); +: asthma attack and/or nocturnal attack of shortness of breath in the last 2 yrs or ever having been diagnosed with asthma; §: regular cough and/or regularly bringing up phlegm; ƒ: persons with a severity score of ≥2 on ≥1 day; ##: Roca et al. 18; ¶¶: n = 43; n = 25; ++: fall of ≥20% in FEV1 associated with a methacholine dose of ≤1 mg; §§: n = 26; n = 17; ƒƒ: specific serum immunoglobulin E level of >0.35 kU·L-1 to at least one of nine common allergens; ###: n = 40; n = 28.
- Table 2—
Associations between cleaning exposures, daily reported symptoms and peak expiratory flow(PEF)
OR (95% CI) Coefficient (95% CI) URTSs# LRTSs¶ PEF at night PEF following morning Working day+ 1.1 (0.6–2.3) 3.1 (1.4–7.1) -3.2 (-8.3–1.9) 0.5 (-4.6–5.5) Daily time cleaning§ 4–8 h 1.0 (0.4–2.5) 2.0 (0.7–5.6) -0.9 (-7.5–5.6) 1.0 (-5.4–7.5) >8 h 2.0 (0.7–6.1) 5.6 (1.7–19) -5.1 (-14–3.5) -1.4 (-9.9–7.1) Cleaning tasksƒ Dusting 1.2 (0.4–3.3) 4.2 (1.5–12) -3.6 (-10–2.9) 2.0 (-4.5–8.5) Vacuuming 2.0 (1.0–4.2) 2.0 (1.0–4.0) -3.9 (-8.6–0.7) 1.1 (-3.8–5.9) Cleaning toilet bowl 0.9 (0.4–2.1) 4.2 (1.9–9.5) 5.9 (0.0–12) 1.1 (-5.0–7.2) Cleaning bathroom 1.5 (0.6–3.6) 3.4 (1.3–8.8) -0.8 (-7.0–5.4) 4.0 (-2.4–10) Cleaning kitchen 1.8 (0.8–4.0) 2.3 (1.1–4.9) 0.1 (-5.8–6.0) 6.5 (0.6–12) Washing dishes 1.0 (0.4–2.7) 1.3 (0.4–4.4) -5.4 (-12–1.0) 0.9 (-5.7–7.5) Ironing 1.9 (0.9–3.9) 1.4 (0.7–2.8) 0.1 (-4.7–4.9) 3.5 (-1.4–8.5) Cleaning productsƒ Bleach Total 1.8 (0.8–4.2) 3.5 (1.4–8.5) 3.5 (-1.9–8.9) 1.7 (-3.9–7.2) Only undiluted 1.4 (0.2–8.4) 1.7 (0.3–10) 9.0 (0.4–18) 3.2 (-5.8–12) Only diluted 1.6 (0.7–3.9) 4.4 (1.8–11) 1.4 (-4.6–7.3) 1.4 (-4.8–7.6) Diluted and undiluted 1.4 (0.5–3.9) 4.4 (1.4–14) 4.3 (-4.0–13) 0.5 (-8.1–9.1) Ammonia## Total 1.8 (0.7–4.9) 1.6 (0.6–4.4) -9.4 (-17– -2.3) -1.2 (-8.5–6.2) Diluted 1.3 (0.3–5.0) 3.0 (1.0–9.1) -10.3 (-18– -2.7) -2.9 (-11– -5.1) Liquid multi-use cleaners 1.3 (0.6–2.9) 2.2 (0.9–5.0) -3.6 (-9.2–1.9) -1.4 (-7.1–4.3) Decalcifiers 0.5 (0.2–1.5) 3.6 (1.6–8.4) -5.2 (-12–1.5) -0.4 (-7.4–6.7) Stain removers 0.9 (0.3–2.8) 2.2 (0.8–5.7) -2.2 (-12–7.8) 6.4 (-3.4–16) Furniture sprays/atomisers 0.7 (0.3–1.5) 2.2 (0.9–5.4) -0.2 (-5.7–5.3) -0.8 (-6.5–5.0) Glass cleaning sprays/atomisers 1.1 (0.6–2.4) 2.9 (1.3–6.4) 0.2 (-5.1–5.5) -0.3 (-5.7–5.2) Degreasing sprays/atomisers 2.2 (1.0–4.8) 6.9 (2.9–16) 6.0 (-0.1–12) -2.9 (-9.2–3.4) Air refreshing sprays/atomisers 1.2 (0.4–3.8) 7.8 (2.6–24) 7.9 (-1.5–17) -4.1 (-14–5.5) OR: odds ratio; CI: confidence interval; URTSs: upper respiratory tract symptoms; LRTSs: lower respiratory tract symptoms. #: blocked nose, watery eyes and throat irritation; ¶: tightness of chest, wheezing, shortness of breath and cough; +: reference category consists of all leisure days, including 188 days cleaning their own home and 8 days without cleaning exposure; §: includes cleaning at work and at home; reference category is days cleaning 0–4 h; ƒ: reference category consists of all days without exposure to the cleaning task/product (either leisure or working day); ##: undiluted ammonia was excluded from analyses because it was used on <10% of days. A separate logistic/lineal mixed model with random intercept was fitted for each exposure. All models were adjusted for the presence of respiratory infection, use of maintenance medication and age. Models for URTSs were additionally adjusted for years of employment in domestic cleaning and weekly working hours in domestic cleaning. Models for LRTSs were additionally adjusted for the daily number of cigarettes smoked, years of employment in domestic cleaning and weekly working hours in domestic cleaning. Only exposures with a p-value of ≤0.1 for any of the outcomes are shown. Cleaning exposures analysed but not shown in the table include sweeping, carpet/rug beating, mopping the floor, cleaning windows/mirrors, cleaning the stove/hob, washing clothes by hand, washing clothes by machine, cooking, using detergents and using sprays for mopping the floor;
- Table 3—
Independent associations between specific cleaning exposures and daily reported symptoms
Exposed days URTSs# LRTSs¶ Cleaning tasks Vacuuming 227 (39) 2.0 (1.0–4.2) NI Cleaning products Diluted bleach 345 (59) NI 2.5 (1.1–5.8) Degreasing sprays+ 206 (35) NI 2.6 (1.1–6.6) Air refreshing sprays+ 79 (14) NI 6.5 (2.1–20) Data are presented as n (%) or odds ratio (95% confidence interval). URTSs: upper respiratory tract symptoms; LRTSs: lower respiratory tract symptoms; NI: not included in the model. #: blocked nose, watery eyes and throat irritation; ¶: tightness of chest, wheezing, shortness of breath and cough; +: including atomisers. Logistic mixed models were fitted that included all exposures presented in the table and a random intercept (n = 582). All models were adjusted for presence of respiratory infection, use of maintenance medication, age, years of employment in domestic cleaning and weekly working hours in domestic cleaning. Models for LRTSs were additionally adjusted for daily number of cigarettes smoked.
- Table 4—
Expert and Oasys(occupational asthma system) scores for individual peak flow record outcomes in cases scoring positively for occupational asthma# by at least one measure
Case No. Ageyrs Smokingstatus Domesticcleaning workyrs Recent respiratorysymptom history¶ Symptomsreported in diary+ Holidayimprovement§ Atopyƒ BHR## Home/workanalysis Bleach/degreaseranalysis URTSs LRTSs Expert Oasys Expert Oasys 1 50 Never 25 A, CB No No Yes¶¶ Yes Yes 3 2.67 3 2.67 2 43 Current 22 CB No Yes No No 3 3 3 1.25 3 44 Former 22 CB No No No No No 2.5 2.75 1 3 4 54 Never 40 A, CB Yes Yes No No 3 4 ID ID 5 48 Never 17 A, CB Yes No No No No 1 1.25 3 3 6 54 Never 32 A, CB Yes Yes No No ID 3 ID 3.67 7 41 Former 8 A Yes No No No Yes ID 3 ID 3 8 39 Former 8 A, CB Yes Yes Yes Yes Yes ID 3 ID ID 9 41 Current 12 A, CB Yes Yes Yes No ID 3.25 ID ID 10 40 Former 13 A, CB No No No No No 1 1.2 ID 3 11 55 Never 26 CB Yes No No No Yes ID ID ID 3 URTSs: upper respiratory tract symptoms; LRTSs: lower respiratory tract symptoms; BHR: bronchial hyperresponsiveness; A: asthma; CB: chronic bronchitis; ID: inadequate data. #: 11 of 37 analysed; ¶: reported at time of either population-based cross-sectional study or case–control study; +: with severity score of ≥2 on ≥1 day; §: self-reported improvement in asthma attacks, wheezing, shortness of breath, cough, phlegm, runny/blocked nose and watery eyes (information from case–control study); ƒ: specific serum immunoglobulin E level of >0.35 kU·L-1 to at least one of nine common allergens; ##: fall of ≥20% in forced expiratory volume in one second associated with a methacholine dose of ≤1 mg; ¶¶: information only available for nose and eye symptoms.
