Review of the epidemiology of allergic rhinitis: insights for the primary health care

Abstract

INTRODUCTION: Allergic rhinitis (AR) is a global health problem with an increasing uptrend of prevalence. Although many epidemiological studies have explored the prevalence of AR on different population, no comprehensive review synthesizes the overall prevalence to inform the global primary health care. This study aims to review and synthesize the overall AR prevalence. METHODS: Published epidemiological AR studies from the past 20 years were searched through electronic databases of MEDLINE and CINAHL. Assessment of study quality was performed separately by two independent researchers. The prevalence, study methods and sample characteristics were extracted, compared and synthesized. RESULTS: Thirty epidemiological studies were included (covering 19 different countries). Majority of them adopted a standard protocol or self-reporting instruments (e.g., ISAAC and SFAR) for screening the AR. The sample size of individual studies ranged from 468 to 165,917 with age range (6-75). The prevalence of AR ranged from 12.7% to 63.0%. Of reviewed studies, three studies with samples of 1200 Mongolians, 17,666 Italians and 22,285 Americans explicitly indicated that the AR prevalence significantly decreased for aged above 40/50. After pooling all the reviewed data, the overall AR prevalence was 28.77% (SD 11.0; 95% confident interval = 24.67-32.86) on average, computed from a total of 533,747 samples. The overall prevalence of Asian studies (n=17; 30.29%, SD 11.95) was higher than that of non-Asian studies (n=13; 26.77%, SD 9.66). Eighteen studies investigated the AR of children (aged 6-18) and 12 studies on adults (aged 18-75) with the overall mean prevalence of 29.27% (SD 11.74) and 28.01% (SD 10.18), respectively. DISCUSSION: This review synthesized 30 epidemiological findings and indicated the overall prevalence of AR as 28.77% on average. Asian population was suffered from AR more than non-Asian. The prevalence of children and adults was equally high regarding AR. Such findings informed that more emphasis on primary health care of AR should be shifted to adults and Asian population.