Risk assessment in elderly for sensitization to food and respiratory allergens

For elderly people, epidemiological data are rare for respiratory allergies and completely missing for food allergies. The aim of this study was to examine the prevalence and risk factors for sensitizations in 109 people with a mean age of 77 years, who are living in a geriatric nursing home. The cross-sectional study included a detailed interview, skin prick tests, and serum tests for specific and total IgE, IFN-gamma, and ST2, a marker for Th2-lymphocyte activity. Almost all study subjects (n=101) suffered from co-morbidity, 14 from type I allergy, 25 from gastrointestinal disorders treated with anti-ulcer drugs, 25 were chronic alcoholics and 21 were smokers. The total IgE levels were significantly higher in men (P=0.025), and not affected by smoking or alcohol consumption. Skin prick tests were positive in 41.7% of tested patients. Specific IgE to respiratory allergens was found in 40.4% of all patients and was elevated in men (P=0.013), with a significant correlation to smoking (P=0.029). Specific IgE to food allergens was detected in 24.8%, apparently without connection to the investigated risk factors. However, positive skin prick tests with food allergens could be correlated with chronic alcohol consumption (P=0.036). The intake of anti-ulcer medication was significantly correlated with elevated ST2 levels as an indirect readout for Th2-cell activity (P<0.001). The risk factors for sensitization in elderly to respiratory allergens were chronic damage of respiratory epithelia due to smoking, and for sensitization to food allergens chronic alcohol consumption.