A cohort study of Parkinson's disease and other neurodegenerative disorders in Danish welders.
OBJECTIVE
We sought to evaluate rates of hospitalizations for neurodegenerative disorders in a cohort of Danish metal manufacturing employees.


METHODS
A retrospective cohort study was conducted from 1977 to 2002 among 27,839 male Danish metal-manufacturing employees, with 9,817 of those employed in departments engaged in mild or stainless-steel welding and 6,163 welders.


RESULTS
The standardized hospitalization ratio and 95% confidence intervals (CI) for Parkinson's disease were 0.9 (CI = 0.7-1.2) for men in steel-manufacturing companies, 1.0 (CI = 0.7-1.5) for men in welding departments, and 0.9 (CI = 0.4-1.5) for welders. Observed numbers for other neurological conditions were small and not above population expectations. Analyses for time period worked, age, and duration of welding were unremarkable.


CONCLUSIONS
This relatively large cohort study with long-term follow-up provides no support for the hypothesis that rates of hospitalization for Parkinson's disease or other neurological conditions are elevated under the exposure circumstances of these Danish workers.
Fryzek
Jon P
JP
International Epidemiology Institute, Rockville, Maryland, USA. fryzek@aol.com
Hansen
Johnni
J
Cohen
Sarah
S
Bonde
Jens Peter
JP
Llambias
Maria Therese
MT
Kolstad
Henrik A
HA
Skytthe
Axel
A
Lipworth
Loren
L
Blot
William J
WJ
Olsen
Jorgen H
JH
D000328:Adult; D017677:Age Distribution; D015331:Cohort Studies; D015897:Comorbidity; D003718:Denmark / Q000453:epidemiology; D005500:Follow-Up Studies; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D019636:Neurodegenerative Diseases / Q000453:epidemiology; D010300:Parkinson Disease / Q000453:epidemiology*; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D014896:Welding / Q000706:statistics & numerical data*