EPIDEMIOLOGY OF ALLERGIC RHINITIS AND ITS ASSOCIATED RISK-FACTORS IN SINGAPORE

Background. Few studies have evaluated the relationship between allerg ic rhinitis and risk factors in the environment which promote aeroalle rgenic exposures, but knowledge of these are of practical importance f rom the point of view of community prevention. Method. A cross-section al population-based study of 2868 adults aged 20-74 years was carried out. Allergic rhinitis was defined as the self-reported presence, in t he previous year, of usual nasal blockage and discharge apart from col ds or the flu, provoked by allergens, with or without conjunctivitis. Results. Allergic rhinitis was reported by 4.5% of the subjects. Highe r crude prevalences were observed in males, younger adults, Indians co mpared to Chinese and Malays, those with higher socioeconomic status, and in three of five residential areas studied. Significant environmen tal factors included cockroach infestation, occupational exposure, pas t smoking habit, outdoor air pollution, and frequent heavy exposure to cooking fumes. Keeping pets, having rugs or carpets in the home, and passive exposure to tobacco smoke showed weak and statistically insign ificant associations. There was no apparent association with use of mo squito coils or incense. The significant determinants after multivaria te adjustment of all risk factors were age, race, flat size, area of r esidence, cockroach infestation, past smoking, and occupational and co oking fumes exposure. Conclusion. The study underscores the importance of environmental control of inhalational exposure to common allergens and irritants in the prevention of allergic rhinitis.