Incidence and prevalence of chronic bronchitis: impact of smoking and welding. The RHINE study.
OBJECTIVE
To investigate the prevalence and incidence rate of chronic bronchitis (CB) in relation to smoking habits and exposure to welding fumes in a general population sample.


METHODS
Subjects from Northern Europe born between 1945 and 1971 who participated in Stage 1 (1989-1994) of the European Community Respiratory Health Survey were mailed a respiratory questionnaire in 1999-2001 (the RHINE study); 15,909 answered the questionnaire and gave complete data on smoking. CB was defined as chronic productive cough of at least 3 months a year for 2 consecutive years. The questionnaire comprised an item about age when CB started and items about exposure to welding fumes. The incidence of CB was retrospectively assessed for the observation period 1980-2001.


RESULTS
CB had a prevalence of 5.4%, and was associated with current smoking and welding exposure. The incidence rate of CB was 1.9 per 1000 person-years, and was increased in relation to welding exposure (low exposure HR 1.4, 95%CI 1.1-1.8; high exposure HR 2.0, 95%CI 1.6-2.7) and in relation to smoking (HR 2.1, 95%CI 1.8-2.5).


CONCLUSIONS
Smoking and occupational exposure to welding fumes are both associated with an increased risk of CB.
Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital, Göteborg, Sweden. mathias.holm@amm.gu.se
M
M
Holm
J-L
JL
Kim
L
L
Lillienberg
T
T
Storaas
R
R
Jögi
C
C
Svanes
V
V
Schlünssen
B
B
Forsberg
T
T
Gíslason
C
C
Janson
K
K
Torén
D000328:Adult; D000395:Air Pollutants, Occupational / Q000009:adverse effects; D029481:Bronchitis, Chronic / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology*; D016273:Occupational Exposure / Q000009:adverse effects*; D015995:Prevalence; D012189:Retrospective Studies; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014896:Welding
D000395:Air Pollutants, Occupational