[Investigation of temporal and spatial characteristics of allergic rhinitis epidemics by Baidu Index in China].

Objective: To explore the temporal and spatial characteristics of search volume (SV) of allergic rhinitis (AR) and related search terms on Baidu Index, as well as the correlation between SV from Baidu Index and epidemiology of AR. Methods: SV of AR and related search terms in mainland area of China from January 2012 to December 2016 were extracted from Baidu Index. Firstly, we investigated the temporal and spatial characteristics of SV of AR and related search terms ("pollen allergy" and" dust mite allergy", etc.), and explored the correlation between SV of AR and SV of related search terms. Secondly, the SV of specific search terms in Beijing and Guangzhou were compared with the actual pollen count in Beijing from April to September in 2016 and the monthly outpatient volume of AR patients in the Otorhinolaryngology Hospital, The First Affiliated Hospital of Sun Yat-sen University from 2014 to 2016 respectively to analyze the consistency between SV from Baidu Index and the real-world data. Spearman correlation analysis was used to explore the correlation between different search terms according to the normality and homogeneity of variance of the data. P<0.05 was considered statistically significant. Results: SV of AR showed repetitively seasonal pattern, with the first peak in May and the second peak from August to September. SV of AR in northeast China, north China and northwest China were correlated with both SV of "pollen allergy" and "dust mite allergy" (r value was 0.533, 0.638, 0.609, 0.791, 0.517, 0.682, respectively, all P<0.05). In east China, central China, south China and southwest China, SV of AR showed significant correlation only with SV of "dust mite allergy" (r value was 0.897, 0.884, 0.799, 0.937, respectively, all P<0.05), but not with SV of "pollen allergy" (r value was 0.110, 0.171, 0.020, 0.265, respectively, all P>0.05). The correlation between pollen count and the SV of AR on the day and SV of "pollen allergy" on the next day was the highest (r value was 0.692 and 0.713, respectively, all P<0.05). The SV of AR was correlated with the monthly outpatient volume of AR patients one month and two months later (r value was 0.523 and 0.503, respectively, all P<0.05). Conclusion: The SV of AR and related search terms show different trends in different times and regions which are consistent with the AR epidemiological survey, and significantly correlate with pollen count and AR outpatient volume.目的： 探讨百度指数平台上变应性鼻炎（allergic rhinitis，AR）及相关检索词的时空分布特征及与AR发病情况的相关性。 方法： 从百度指数平台提取2012年1月至2016年12月中国大陆地区的AR检索词，分析"过敏性鼻炎"及相关检索词（"花粉过敏"和"尘螨过敏"等）搜索量的时间和空间分布特征，探究"过敏性鼻炎"搜索量与相关检索词搜索量的相关性。将北京和广州地区特定检索词的搜索量分别与2016年4—9月北京地区实际花粉浓度及2014—2016年中山大学附属第一医院耳鼻咽喉科医院的AR患者月门诊量进行比较，分析其与真实数据的一致性。根据数据的正态性和方差齐性，采用Spearman相关性分析探索不同检索词之间的相关性。P<0.05为差异有统计学意义。 结果： 我国的"过敏性鼻炎"搜索量呈明显的季节性变化。第一个峰值出现在5月，第二个更高的峰值出现在8~9月。空间方面，在东北、华北、西北地区， "过敏性鼻炎"搜索量与"花粉过敏"及"尘螨过敏"搜索量呈正相关（r值分别为0.533、0.638、0.609、0.791、0.517、0.682，P值均<0.05）。而在华东、华中、华南和西南地区， "过敏性鼻炎"搜索量只与"尘螨过敏"搜索量相关（r值分别为0.897、0.884、0.799、0.937，P值均<0.05），与"花粉过敏"搜索量不相关（r值分别为0.110、0.171、0.020、0.265，P值均>0.05）。花粉浓度与当日的"过敏性鼻炎"搜索量及次日的"花粉过敏"搜索量相关程度最高（r值分别为0.692、0.713，P值均<0.05）。 "过敏性鼻炎"搜索量与1个月后及2个月后AR患者的月门诊量相关（r值分别为0.523、0.503，P值均<0.05）。 结论： AR及相关检索词的搜索量在不同时空呈现不同趋势，与AR流行病学调查结果相符，并与花粉浓度和AR门诊量具有显著相关性。.