Prevention (cont’d)
Disposition question: Whether to allow individual with established LAA to continue working using PPE, or to remove from position?
Portengen, Hollander, Doekes, & Heederik. Lung Function decline in laboratory animal workers: the role of sensitization and exposure. Occupational and Env Med 2003;60: 870-875.
Studied relation between sensitization and subsequent lung function decline in working populations exposed to allergen(s).
Method: longitudinal study (median follow up 2.0 years) – 319 lab animal workers- excluded subjects with over 4 years exposure
Results:
Multiple regression analyses-
Lung function decline most pronounced in sensitized subjects who continued to work in contact with lab animals
Average excess declines FEV1= 83 ml/y (p<0.05)
FVC = 148 ml/y (p<0.01)
MMEF = 7 ml/s/y (p=0.9)
Results corroborate findings of other studies
Renstrom et al( Eur Respi J 1995 )
Sjosted et al (Am J Ind Med,1993)
Proposed mechanism: Malo et al, (J Allergy Clin Immunol 1992) – chronic inflammation develops after sensitization, but before development of symptoms
Low level inflammation leads to decline in lung function with continued exposure
Study flaws- short follow up, ? Small sample size, unclear if workers “continually exposed” used PPE