Prevalence of pollen‐induced allergic rhinitis with high pollen exposure in grasslands of northern China

Abstract

BackgroundThe aim of this study was to investigate the prevalence of epidemiologic and physician‐diagnosed pollen‐induced AR (PiAR) in the grasslands of northern China and to study the impact of the intensity and time of pollen exposure on PiAR prevalence.MethodsA multistage, clustered and proportionately stratified random sampling with a field interviewer‐administered survey study was performed together with skin prick tests (SPT) and measurements of the daily pollen count.ResultsA total of 6043 subjects completed the study, with a proportion of 32.4% epidemiologic AR and 18.5% PiAR. The prevalence was higher in males than females (19.6% vs 17.4%, P = .024), but no difference between the two major residential and ethnic groups (Han and Mongolian) was observed. Subjects from urban areas showed higher prevalence of PiAR than rural areas (23.1% vs 14.0%, P < .001). Most PiAR patients were sensitized to two or more pollens (79.4%) with artemisia, chenopodium, and humulus scandens being the most common pollen types, which were similarly found as the top three sensitizing pollen allergens by SPT. There were significant regional differences in the prevalence of epidemiologic AR (from 18.6% to 52.9%) and PiAR (from 10.5% to 31.4%) among the six areas investigated. PiAR symptoms were positively associated with pollen counts, temperature, and precipitation (P < .05), but negatively with wind speed and pressure P < .05).ConclusionPollen‐induced AR (PiAR) prevalence in the investigated region is extremely high due to high seasonal pollen exposure, which was influenced by local environmental and climate conditions.

Recent developments and highlights in allergic rhinitis

“…Aeroallergens (pollens, molds, and HDM) are important inhaled particles and major causes of AR. Wang and colleagues reported that in Northern China, the prevalence of epidemiologic and pollen‐induced AR is 32.4% and 18.5%, respectively. Several studies showed that the incidence or severity of AR is closely correlated with levels of pollen allergens in ambient air in multiple countries and regions .…”

“…33,36,41,42 Climate change affects vegetation, resulting in changes in the start, duration, intensity, and distribution of allergenic pollen. 33,36,41,43,44 Biedermann et al 36 have shown that climate change has increased the levels of birch pollen and period of exposure, with a higher prevalence of birch pollen sensitization. The extremely high prevalence of pollen-induced AR in the grasslands of Northern China is associated with high seasonal pollen exposure influenced by local environmental and climate conditions.…”

“…The extremely high prevalence of pollen-induced AR in the grasslands of Northern China is associated with high seasonal pollen exposure influenced by local environmental and climate conditions. 33 When the nasal mucosa is exposed to inciting allergens such as pollen and dust mites, innate and adaptive immune cells are involved in the pathophysiologic mechanism of AR, which induce specific immunoglobulin E (IgE) production, activation of eosinophils, and degranulation of mast cells and basophils, 45 with the consequent clinical symptoms of AR. adjusted symptom score (AASS) reduction of more than 30% from the baseline after sublingual immunotherapy (SLIT).…”

Effect of Cellulose Powder on Human Nasal Epithelial Cell Activity and Ciliary Beat Frequency

“…Furthermore, the epidemic of AR in some major cities of China has increased considerably. A high prevalence of AR (18.6–52.9%) and physician-diagnosed AR (10.5–31.4%) has also been seen in northern China where gross pollen levels are high [4]. The prevalence of sensitization to aeroallergens in patients with AR also increased from 69.7 to 76.6% in Guangzhou in 2005–2014 [5].…”

Associations among air pollutants, grass pollens, and daily number of grass pollen allergen‐positive patients: a longitudinal study from 2012 to 2016

“…A recent multicenter epidemiologic study in China revealed that grass pollens were the most prevalent sensitizing aeroallergens in north China; in particular, sensitization rates for Artemisia pollen were 58.2% in northwest China . Another epidemiological study in the northern grassland regions of China also suggested that grass pollens were the most common allergens . Our previous studies have indicated that major airborne pollen allergens are derived from grass during July to September in Beijing, China; the major pollens are Artemisia L., Chenopodium album , and Humulus scandens…”