Table 1

Effect size of COPD associated with solid fuel smoke exposure

ReferenceCountryTypes of studyFuel typeSample sizeExposure measuredTypes of diagnosisSample typeEffect size
%OR (95% CI)
Dossing et al 199420Saudi ArabiaCC study defined by diseasesWood50 cases, 71 controlsNo direct measurementFEV1/FVC <70% and FEV1<70% of predicted value; <15% or <250 ml absolute reduction of FEV1 after inhalation of 200 μg aerosolised salbutamolAdults with COPD88 vs 3417.42 (10.58 to 28.68)
Dennis et al 199631ColumbiaCC study defined by diseasesWood and gasoline104 cases, 104 controlsNo direct measurementFEV1/FVC <70% and FEV1<70% of predicted valueWomen ≥35 years with COPD85 vs 623.92 (1.7 to 9.1)
Orozco-Levi et al 200616SpainCC study defined by diseasesWood (W), charcoal (C) or both (B)60 cases (hospitalised), 60 controlDuration of exposure reported.FEV1/FVC <70% and FEV1<80% of predicted value; <12% change in FEV1 after inhalation of 400 μg inhaled salbutamolWomen >50 years with COPD95 vs 72W: 1.8 (0.6 to 6.0), C: 1.5 (0.5 to 4.6)), B: 4.5 (1.4 to 14.2)
Regalado et al 200632MexicoCS studyBiomass and gasBiomass 778, gas 67PM10 measured for 1 h during cookingGOLD (G) criteria for diagnosis of COPDNon-smoking adult womenBiomassBiomass: G I
G I: 13.5
G II: 2.7
1.5 (0.5 to 4.3)
Gas G I: 9.1
Liu et al 200714ChinaCS studyBiomass (BM), coal (C) and LPGCombined BM 1306Measured SO2, NO2, CO and PM10 directlyGOLD criteria for diagnosis of COPDAdults ≥ 40 years12.0 (BM)BM: 1.72 (1.27 to 2.35)
C 17212.2 (C)C: 1.55 (0.74 to 3.22), LPG=reference
LPG 18087.3 (LPG)
Non-smoking women ≥40 years7.3 (BM)BM: 3.11 (1.63 to 5.94)
Non-smoking women BM 744 C 90 LPG 9956.7 (C)C: 2.77 (0.83 to 9.26), LPG=Reference
2.5 (LPG)
Zhong et al 200722ChinaCS studyBiomass10 661 (never exposed); 9 584 (ever exposed)Not measured directlyGOLD criteria for diagnosis of COPDAdults ≥ 40 years9.3 (ever exposed),1.35
(1.20 to 1.52)
7.3 (never exposed)
Caballero et al 200833ColumbiaCS studyWood exposed ≥10 years2175 (not exposed); 3364 (ever exposed)Not measured directlyFEV1/FVC ratio<70% after bronchodilator (200 μg salbutamol)Adults ≥ 40 years13.4% (exposed for ≥10 years)2.42 (2.0 to 2.92) (exposed for ≥10 years)
Xu et al 200715ChinaCC study defined by exposure to solid fuel and smokingElectricity/gas,coal, firewood/straw1743 cases, 1743 controlsNo direct measurementHospital diagnosedAdults ≥35 years74.1 (electricity/gas), 2.7 (coal) and 23.2 (firewood/straw)1.32 (0.79 to 2.20) (coal user) and 0.71 (0.46 to 1.10) (firewood/straw)
Chapman et al 200534ChinaRetrospective cohort study
(switched to chimney stove)
Coal20453No direct measurementHospital diagnosed16606 (81.2%) had chimney stove and 3847 (18.8%) no chimney stove19.4% (no chimney stove) and 4.5% (changed to chimney stove)5.15 (4.62 to 5.74)
Sezer et al 200435TurkeyCC study defined by diagnosis of COPDBiomass74 COPD cases and 74 non-COPD cases (healthy)No direct measurementHospital diagnosedNon-smoking women ≥38 years75.7% cases and 70.3% controls exposed to biomass6.61 (2.17 to 20.18) in women exposed to biomass ≥30 years
Ekici et al 200536TurkeyCC study defined by fuel typesBiomass and LPGBiomass (cases)=397
LPG (control)=199
No direct measurementBMRC criteria for the diagnosis of CB and CAO defined by FEV1/FVC<70Non-smoking women > 40 years23.12.5 (1.4 to 4.0)
Kiraz et al 200321TurkeyCC study defined by fuel typesBiomass and LPGBiomass=242 and non-biomass=102No direct measurementATS and BMRCAdult women12.4 vs 3.928.9 (8.7 to 95.9)
  • ATS, American Thoracic Society; BMRC, British Medical Research Council; CAO, chronic airway obstruction; CB, chronic bronchitis; CC, case–control; COPD, chronic obstructive pulmonary disease; CS, cross-sectional; DS, descriptive study; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; GOLD, Global Initiative for Obstructive Lung Disease; LPG, liquefied petroleum gas; PM10, particles of ≤10 μm.