IgE level and Phadiatop in an elderly population from the PAQUID cohort: relationship to respiratory symptoms and smoking

BACKGROUND: In the last decades in industrialized countries, the increase of life expectancy has resulted in an increase in the population of the elderly. However, little is known about the prevalence of allergies in the elderly population. The aim of the study was to investigate the specific relationship of serum IgE and Phadiatop, with asthma, rhinitis, and smoking in a sample of an elderly population. METHODS: Subjects from the Paquid cohort living in Gironde Department (age 65 years and over) in France were followed up since 1988 (PAQUID cohort). RESULTS: Among the randomized sample of 352 subjects, there were 158 men (45%) and 194 women (55%). The lowest levels of IgE were in subjects with chronic sputum; and in normal subjects (47.1 +/- 56.4 vs 56.2 +/- 73.9, NS). Multiple linear regression was performed with log(10) IgE values as a dependent variable and age, Phadiatop test, smoking, and respiratory symptoms independently in men and in women. In men, a significant relationship was observed between IgE values and Phadiatop test (P < 0.001), asthma history (P = 0.002), and smoking (P = 0.019). CONCLUSIONS: Respiratory allergy is present in persons >65 years of age. There is an association between smoking and IgE level independent of allergic reactivity to common allergens in the elderly.