Allergen sensitization profiles in total cohort
For skin and serological tests, the positive rate of HDMs (Der p and Der f) was the highest, all more than 60%, followed by Blot t (SPT: 63.3%, sIgE: 34.29%) (Figure 2). For cockroach and dog dander allergens, the positive rate detected by skin prick test was significantly higher than serological test (36.17% vs. 12.86% and 35.11% vs. 7.86% respectively, P <0.05). The positive rates of cat hair, fungus (Asp f and Cand a) and common ragweed allergens were lower than 10%.
In addition, we also compared the method consistency of skin test and serological test (N=127, Table 1). The consistency of the two methods ranged from 61% to 96%, and the consistency of common ragweed was the best. However, because the number of positive cases of common ragweed is very small, the kappa value is the worst (0.01 (-0.03-0.01)). Der f and cat dander has the highest kappa coefficient (0.62 (0.47-0.78) and 0.60 (0.37-0.84) respectively), and their consistency is 85.04% and 92.91%.
Clinical characteristics and allergen positive rate in patients with AR with or without AS
A total of 270 patients with rhinitis were included in this study, including 93 patients with simple rhinitis and 177 patients with rhinitis and asthma. Most demographic information and environmental exposures were not significantly different between the two groups. However, significant differences in age and family allergy history were observed between AR and AR&AS. The median age (IQR) of the AR patients was 28 (14, 35), and 61.29% (57/93) AR patients had a family allergy history while only 33.90% (60/177) in AR&AS patients (P =0.001) (Table 2).
Similar to the total cohort, the results of SPT and serological test showed that the positive rate of HDMs (Der p and Der f) was the highest, and the positive rate of them in patients with simple AR were higher than that in AR&AS. The positive rates of cockroach and dog dander were significantly different between SPT and serological test methods, but there was no difference between combined with or without asthma. The positive rates of other allergens were all less than 10.00%, and there was no difference in the positive rate between the two groups (Figure 3).
Clinical characteristics and sensitization profile in child and adult patients
The characteristics of patients grouped by age are shown in Table 3. In this study, 75.2% (203/270) were adults and 24.8% (67/270) were children. Male patients accounted for 65.7% and 46.8% in children and adults, respectively, and it was statistically different in the sex composition ratio between the two groups (P =0.007). The number of adult smokers was higher than that of children (13.79% vs. 1.49%, P =0.005). It was worth noting that children are more susceptible to multiple allergens than adults (sIgE: 91.43% vs. 61.90%, P =0.004). Moreover, total IgE levels were higher in children than in adult patients (368.48 IU/mL vs. 139.10 IU/mL, P <0.001).
Compared with adult patients, children had higher positive rate of HDMs (Der p and Der f) in the results of SPT and serological test (P <0. 05), while there was no significant difference in other allergens between the two groups (Figure 4).
Clinical characteristics and sensitization profile in different severity
According to ARIA guidelines, 117 (43.33%) cases were defined as moderate to severe rhinitis, and we further compared the clinical characteristics of patients with mild and moderate to severe rhinitis (Table 4). The results showed that the age of patients with moderate to severe rhinitis was lower than that of patients with mild rhinitis (28 (16,39) vs. 33 (21,49), P =0.010). Compared with patients with mild rhinitis, a higher percentage in moderate to severe patients reported a history of being informed of AR in the past, and higher proportion reported combined symptoms of eyes and pulmonary (all P < 0.05). However, for allergen sensitization (both sIgE and SPT), the multiple sensitization rate of patients with moderate and severe rhinitis was slightly higher than that of patients with mild rhinitis, but the difference was not statistically significant (P >0.05). In addition, there was no difference in other variables including gender, smoking history, family history of allergies, animal exposure and living environment between the two groups.
The positive rates of the 9 allergens (both SPT and sIgE) were similar between the mild and moderate to severe rhinitis groups, and there was no significant difference (Figure 5).
Analysis of specific symptoms of nose and lungs in different groups
Almost all (more than 94%) of patients with allergic rhinitis develop nasal and eye symptoms including stuffy nose, runny nose, sneezing, itchy nose, itchy eyes or tears when exposed to cold air (Table 5). Secondly, pollen exposure was also one of the causes of rhinitis symptoms. In each group, the reporting rate of rhinitis symptoms caused by pollen exposure was 33.33% - 44.07%, and the difference between groups was not statistically significant. The reporting rate of rhinitis symptoms caused by furry animal exposure were about 25% in all groups, and there was no difference between groups. With or without asthma and different age groups, there was no difference in the incidence of rhinitis symptoms in four seasons, but the incidence of rhinitis symptoms in moderate to severe patients was higher than that in mild patients (all P <0.05).
In addition, we also analyzed the differences of combined pulmonary symptoms between groups, including wheezing, chest tightness, cough. Despite being diagnosed with simple rhinitis, 41.94% of patients reported symptoms of cough, 19.35% reported chest tightness and 8.60% reported wheezing. Among the patients with AR&AS, 97.18% reported the symptoms of wheezing, 70.06% reported chest tightness and 75.14% reported wheezing. For any kind of pulmonary symptoms, the reporting rate of AR&AS patients was higher than that of AR patients (all P <0.05). In addition, the percentage of pulmonary symptoms reported by children was significantly lower than that of adults (P <0.05). Consistent with it, the reporting rate of children using drugs to control pulmonary symptoms was lower than that of adults (52.24% vs. 68.47%, P =0.016). There was no difference in the proportion of pulmonary symptoms among patients with rhinitis of different severity.