Risk of COPD from exposure to biomass smoke: a metaanalysis.
BACKGROUND
Although many studies have suggested that biomass smoke is a risk factor for COPD, the relationship between the two has not been firmly established. In particular, the extent of the association between exposure of biomass smoke and COPD in different populations, as well as the relationship between biomass smoke and cigarette smoke, is not clear. To ascertain the relationship between biomass smoke and COPD, we performed a metaanalysis.


METHODS
We searched MEDLINE, EMBASE, and the Latin American and Caribbean Literature in Health Sciences Database and analyzed 15 epidemiologic (11 cross-sectional and four case-control) studies that met our criteria. Data were extracted and analyzed independently by two investigators using a standardized protocol.


RESULTS
Overall, people exposed to biomass smoke have an odds ratio (OR) of 2.44 (95% CI, 1.9-3.33) for developing COPD, relative to those not exposed to biomass smoke. Biomass smoke exposure was clearly identified as a risk factor for developing COPD in both women (OR, 2.73; 95% CI, 2.28-3.28) and men (OR, 4.30; 95% CI, 1.85-10.01), and in both the Asian population (OR, 2.31; 95% CI, 1.41-3.78) and the non-Asian population (OR, 2.56; 95% CI, 1.71-3.83). This risk factor has also been revealed in patients with chronic bronchitis (OR, 2.56; 95% CI, 1.77-3.70) and COPD (OR, 2.65; 95% CI, 1.75-4.03), and in cigarette smokers (OR, 4.39; 95% CI, 1.40-4.66) and non-cigarette smokers (OR, 2.55; 95% CI, 2.06-3.15).


CONCLUSIONS
Exposure to biomass smoke is a risk factor for COPD.
Guangzhou Institute of Respiratory Diseases, State Key Laboratory of Respiratory Diseases, The First Affiliated Hospital, Guangzhou Medical University, 151 Yanjiang Rd, Guangzhou, Guangdong, 510120, China.
Guoping
G
Hu
Yumin
Y
Zhou
Jia
J
Tian
Weimin
W
Yao
Jianguo
J
Li
Bing
B
Li
Pixin
P
Ran
D000393:Air Pollutants / Q000009:adverse effects*; D005260:Female; D014943:Global Health; D006801:Humans; D015994:Incidence; D008297:Male; D052638:Particulate Matter / Q000009:adverse effects*; D029424:Pulmonary Disease, Chronic Obstructive / Q000139:chemically induced* / Q000453:epidemiology; D012906:Smoke / Q000009:adverse effects*
D000393:Air Pollutants; D052638:Particulate Matter; D012906:Smoke