Cord blood LC-PUFA composition and allergic diseases during the first 10 yr. Results from the LISAplus study

BACKGROUND It has been suggested that n-6 and n-3 long-chain polyunsaturated fatty acids (LC-PUFAs) in blood are associated with risk of allergic diseases, although results are inconclusive. Low levels of n-6 LC-PUFA and high levels of n-3 LC-PUFA are anticipated to have beneficial effects. Pregnancy is considered a critical time period for imprinting the developing immune system. We examined whether n-6 LC-PUFA, n-3 LC-PUFA concentrations or the n-6/n-3 ratio in cord blood (CB) serum are associated with allergic diseases up to the age of 10 yr. METHODS This analysis included 436 children from the Munich LISAplus birth cohort study. Information on doctor-diagnosed asthma, hay fever/allergic rhinitis, and eczema was collected using questionnaires completed at the ages 6 and 10 yr, and for eczema additionally at 2 yr. Specific immunoglobulin E (IgE) against inhalant allergens was measured at 6 and 10 yr. Fatty acid composition was measured by gas chromatography in serum from CB and from blood collected at 2, 6, and 10 yr. Associations between n-3, n-6 LC-PUFA concentrations, and the n-6/n-3 ratio in CB serum and allergic diseases or atopy were assessed using generalized estimating equations (GEE) considering the longitudinal structure. Models were adjusted for LC-PUFA concentrations at follow-up and potential confounding factors. RESULTS There was no significant association between n-3 LC-PUFA, n-6 LC-PUFA, or the n-6/n-3 ratio in CB serum with eczema, asthma, hay fever/allergic rhinitis, or aeroallergen sensitization. CONCLUSIONS There is no indication of a beneficial effect of increased n-3 LC-PUFA in CB serum on the development of any of the disease entities.