Myocardial infarction among Swedish cooks and kitchen workers

Introduction:  There are epidemiological studies indicating an increased risk of myocardial infarction (MI) among cooks. One hypothesis is that exposure to air pollution generated during cooking and frying contributes to the excess risk. The aim of this study was to investigate the association between occupation as a cook or other kitchen worker and incidence of MI, using workers in the same socioeconomic group as referents.    

Methods:  A cohort was created including manual workers in the service sector in the Swedish National Census in 1985, in total 543 497 women and 233 999 men. Information on first time MI during 1987-2005 was obtained from nation-wide registers. Cooks, cold-buffet managers, restaurant-and kitchen assistants and wait staff were identified by occupational codes from censuses in 1985 and 1990, as well as socioeconomic status. The association between occupation and MI was estimated through Cox proportional hazards modeling, with separate analyses for women and men, adjusting for age, hypertension and diabetes.    

Results:  Among women there was an increased HR for MI among cooks (HR 1.34, 95 % CI 1.21-1.48), restaurant-and kitchen assistants (HR 1.17, 95% CI 1.08-1.26) and wait staff (HR 1.24, 95% CI 1.06-1.47), but not among cold buffet managers. Among men there was no increased HR for MI in any of these occupations. The association was not stronger for subjects with a long work duration.    

Discussion:  We found an increased risk of MI among female cooks, restaurant- or kitchen assistant and wait staff, but not among male cooks or kitchen workers. Potential explanations for the increased risk among women are differences in the occupational exposure situation between women and men, a higher sensitivity to exposure to cooking fumes in women, or confounding from smoking or other risk factors, although potential confounding from lifestyle factors was limited by restriction to the same socioeconomic group.