Objective: To investigate whether genetic variants involved in cytokine expression are associated with the age-related rate of decline in forced expiratory volume in 1 second (FEV1).
Methods: Functional polymorphisms in the TNFalpha, TGF beta 1, IL-1 beta, IL-1RN, IL-13, and IL-8 genes were investigated in 374 active firefighters with at least five pulmonary function tests.
Results: A protective effect was found between the presence of the TGF beta 1 -509 TT genotype and rate of decline in FEV1 (P = 0.043). Carrying an A allele at TNFalpha -308 (P = 0.010) and GG genotype at TNFalpha -238 (P = 0.028) was associated with a more rapid rate of FEV1 decline. The TNFalpha -308A/-238G haplotype was also associated with an increased rate of decline as compared with the other haplotypes.
Conclusions: Interindividual variability in progressive decline in FEV1 may be explained in part by genetic variations within genes involved in inflammatory responses.