Clinical and Experimental Otorhinolaryngology 2017 August 1 [Epub ahead of print] https://doi.org/10.21053/ceo.2017.

00500
pISSN 1976-8710 eISSN 2005-0720
Original Article

The Impact of Allergic Rhinitis on Symptom

Improvement in Pediatric Patients After
Adenotonsillectomy
Dong-Jun Lee*Young-Jun Chung*Yeon-Jun YangJi-Hun Mo

Department of Otorhinolaryngology, Dankook University College of Medicine, Cheonan, Korea

Objectives. It is well known that allergic rhinitis (AR) has positive association with adenotonsillectomy. However, the im-
pact of AR on symptom improvement after adenotonsillectomy is not well documented. Hence, we aimed to evalu-
ate the effect of AR on the symptom improvement after adenotonsillectomy between AR and nonallergic patients.
Methods. A retrospective analysis was performed on 250 pediatric patients younger than 10 years old who received adeno-
tonsillectomy from June 2009 to June 2014 in a tertiary referral hospital. All patients underwent skin prick test or
multiple allergen simultaneous test (MAST) before surgery and classified into AR group and control group. Obstruc-
tive and rhinitis symptoms including snoring, mouth breathing, nasal obstruction, rhinorrhea, itching, and sneezing
were evaluated before and 1 year after surgery using questionnaire and telephone survey.
Results. AR group was 131 and control group was 119, showing higher prevalence (52.4%) of AR among adenotonsillecto-
mized patients. Both groups showed dramatic improvement of symptoms such as snoring and mouth breathing after
surgery (all P <0.05). However, AR group showed significantly less improvement than control group in snoring,
mouth breathing, nasal obstruction, and rhinorrhea (all P<0.05). Multivariate analysis showed that preoperative
mouth breathing and snoring were dependent on tonsil grade and postoperative symptoms were mainly dependent
on presence of AR. Nasal obstruction was dependent on tonsil grade and presence of AR preoperatively and presence
of AR postoperatively. These suggest the importance of AR as a risk factor for mouth breathing, snoring, and nasal
obstruction.
Conclusion. AR has positive association with adenotonsillectomy and not only allergic symptoms but also obstructive
symptoms such as snoring and mouth breathing improved less in AR group than control group. Hence, patients with
AR should be monitored for long-term basis and more carefully after adenotonsillectomy.
Keywords. Adenoidectomy; Allergic Rhinitis; Child; Tonsillectomy

INTRODUCTION adenotonsillectomy. Adenotonsillectomy can resolve upper air-

way obstruction in about 80%90% of children. However, since
The most common cause of upper airway obstruction in chil- many children underwent adenotonsillectomy, the remaining
dren is adenotonsillar hypertrophy and it is usually treated with 10% to 20% of patients were still large numbers and they com-
plained of obstructive symptoms such as snoring and nasal ob-
Received May 5, 2017 struction even after adenotonsillectomy during their long fol-
Revised July 5, 2017
Accepted July 13, 2017 low-up periods [1].
Corresponding author: Ji-Hun Mo Several studies have reported the postoperative outcomes of
Department of Otorhinolaryngology, Dankook University College of adenotonsillectomy; however, most of them are short-term out-
Medicine, 119 Dandae-ro, Dongnam-gu, Cheonan 31116, Korea
Tel: +82-41-550-3933, Fax: +82-41-556-1090
comes rather than long-term ones [2]. It has been reported that
E-mail: jihunmo@gmail.com in some patients, airway problems persist or recur over long-
*The first two authors contributed equally to this study. term follow-up, although the causes for this is not clear yet [3].
Copyright 2017 by Korean Society of Otorhinolaryngology-Head and Neck Surgery.
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0)
which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

page 1 of 6
page 2 of 6 Clinical and Experimental Otorhinolaryngology

In addition, the relationship between adenotonsillectomy and sal obstruction, rhinorrhea, itching, and sneezing were evaluated
postoperative airway symptoms has not been clarified till date. using a visual analogue scale (VAS) from 0 (no symptom) to 10
Thus, the successful maintenance of improved airway status af- points (very severe symptoms). For postoperative symptoms, a
ter adenotonsillectomy in children remains partially challenging telephonic survey was conducted to investigate any change in
for otolaryngologists. symptoms at least one year after surgery. Primary caregivers
Although allergic rhinitis (AR) is an important risk factor for completed preoperative and postoperative questionnaires in
tonsil and adenoid hypertrophy [4] and also a major factor af- most cases.
fecting the quality of life of children, there have been few stud-
ies on the allergic status in children after adenotonsillectomy. Preoperative physical examination
Moreover, there is a paucity of data indicating that AR may in- Adenotonsillar enlargement was determined physical examina-
fluence the postoperative outcomes of adenotonsillectomy. tion and cephalometry. Tonsillar hypertrophy was graded from 0
Therefore, we aimed to compare the improvement in symp- to 4 according to the Friedman staging system [5]. Adenoid hy-
toms after adenotonsillectomy between patients with and with- pertrophy was graded using the adenoid/nasopharynx ratio,
out AR, and to reveal the factors affecting the pre- and postop- which is well described in the literature; grade 1 denotes 0% to
erative improvements in symptoms. 25% hypertrophy, grade 2 denotes 25% to 50%, grade 3 de-
notes 50% to 75%, and grade 4 denotes 75% to 100% hyper-
trophy [6].
MATERIALS AND METHODS
Skin prick test and multiple allergen simultaneous test
Subject Skin prick tests were performed with 50 common aeroallergens
Two hundred and eighty-two patients under the age of 10 years, including house dust mite, grass, tree, weed, feathers, cockroach,
who underwent adenotonsillectomy by single surgeon from cat, dog, and moulds. All skin test and test reading were per-
June 2009 to June 2014 in a tertiary referral hospital, were ini- formed by experienced personnel.
tially recruited in this study. Among them, 32 patients whose For each allergen, we measured the largest diameter of the
chief complaint was other than obstructive symptoms (frequent wheal and the diameter orthogonal to it; we then calculated the
tonsillitis, 23; frequent otitis media, 5; and rhinosinusitis, 4 cas- mean. A positive reaction was defined as a mean wheal diame-
es, respectively) were excluded. In addition, 3 patients with sub- ter more than or equal to that of histamine (positive control). All
clinical allergy were also excluded. Their mean age was 6.02.2 the saline controls were negative. Patients were considered aller-
years and male: female ratio was 140:110. gic if they had at least one positive skin prick test to any of the
A retrospective chart review was performed to collect data. allergens tested [7]. When patients were too young to perform
All the subjects underwent skin prick test or multiple allergen skin prick test or taking medications interfering with the skin
simultaneous test (MAST) and they completed questionnaires. prick test reaction, MAST was performed as follows; Patient se-
AR was confirmed by the presence of the typical symptoms and rum was added to MAST pette chambers, which contained 30
positive skin prick test or MAST. Subjects were classified into kinds of allergens. After 2 hours of incubation and washes, en-
AR group and control group depending on the presence of AR. zyme-tagged anti-immunoglobulin E (IgE) was added. After an-
other 2 hours of incubation and washes, luminescent reagent
Symptom questionnaires was added. After 10 minutes of incubation, the results were in-
Preoperative symptoms including mouth breathing, snoring, na- terpreted as class 04, using MAST OPTIGEN luminometer
(Hitachi Chemical Diagnostics, Inc., Mountain View, CA, USA).
Class 2 was interpreted as positive [8].
H I G H L I G H T S
Data evaluation and statistical analysis
 llergic rhinitis (AR) is more prevalent in adenotonsillecto-
A Paired comparison t-test was used to compare symptoms before
mized children than general population.
and after surgery. Symptomatic changes were compared be-
Patients with AR had more severe symptoms including snor- tween AR and control groups. Student t-test was used to analyze
ing, nasal obstruction and rhinorrhea preoperatively. the differences between the two groups. The association be-
Both obstructive symptoms such as snoring, mouth breathing, tween symptoms (mouth breathing, snoring, nasal obstruction,
and allergic symptoms improved significantly less in patients rhinorrhea, itching, and sneezing) and related factors including
with AR.
sex, asthma, allergy, adenoid grade, and tonsil grade was ana-
Hence, patients with AR should be monitored for long-term lyzed using logistic regression analysis. All the parametric results
basis and more carefully after adenotonsillectomy due to re- are expressed as meanstandard deviations. Statistical signifi-
maining symptoms.
cance was assumed at P<0.05 for all the parameters.
 Lee DJ et al. The Impact of Allergic Rhinitis After Adenotonsillectomy page 3 of 6

RESULTS nificantly higher in AR group than in control group (Table 2).

Demographic data Postoperative symptom improvement

Among 250 patients, 131 had AR (AR group) and 119 did not Symptoms including mouth breathing, snoring, rhinorrhea, and
have AR (control group). Mean ages were 6.12.1 years and nasal obstruction were significantly improved postoperatively in
5.92.1 years in the AR and control group, respectively and both groups. Symptom improvements in control group was sig-
mean follow-up periods were similar in both groups (25.210.2 nificantly higher than those in the AR group (all P<0.05) (Fig. 1).
months and 26.411.3 months, respectively). Only one child in The itching symptom had statistically significant improvement
the AR group had asthma out of the 250 patients (Table 1). in the AR group, but not in the control group before and after
surgery; the degree of symptom improvement was greater in the
Preoperative symptoms AR group. Sneezing did not show any statistically significant im-
The most severe symptoms in the AR group was nasal obstruc- provement before and after surgery, and there was no statistical-
tion (average symptom score, 8.521.61), followed by snoring, ly significant difference in symptom change between the two
rhinorrhea, itching, sneezing, and mouth breathing with average groups (Fig. 1).
symptom scores of 7.931.62, 7.832.52, 7.813.31, 7.32
3.24, and 7.022.51, respectively. Control group complained of The influence of the size of the tonsils and adenoids on symp-
mouth breathing as the most severe symptom followed by nasal tom improvement
obstruction, snoring and rhinorrhea. Itching and sneezing symp- We then analyzed postoperative symptom improvement accord-
tom scores were significantly lower in control group (P<0.01). ing to the grade of the tonsils and adenoids, and compared them
Most of the symptom scores except mouth breathing were sig- between the two groups. Obstructive symptoms like mouth
breathing and snoring were significantly improved after surgery
Table 1. Demographic data of the patients in both groups and they were dependent on the Friedman tonsil
AR group Control group
Demographic P-value Preoperative Postoperative
(n=131) (n=119)
Age (yr) 6.12.1 5.92.1 NS * *
10 * ** 10 ** **
Sex (male:female) 78:53 62:57 0.023
Tonsil grade -

VAS
5
VAS

I 21 17 5
II 42 40
III 56 43 0 0
AR group Control group A AR group Control group B
IV 12 19
Adenoid grade -
* *
I 25 18 * ** * **
10 10
II 39 34
III 54 51
VAS

VAS

5 5
IV 13 16
Associated condition
Asthma 1 0 NS 0 0
AR group Control group C AR group Control group D
Follow-up period (mo) 25.210.2 26.411.3 NS
Values are presented as number or meanstandard deviation. **
10
**
AR, allergic rhinitis; NS, nonsignificant. 10

Table 2. Preoperative symptoms of AR group and control group

VAS

VAS

5 5

Preoperative VAS score

0 0
Symptom AR group Control group AR group Control group E AR group Control group F
P-value
(n=131) (n=119)
Mouth breathing 7.022.51 7.512.32 NS Fig. 1. Postoperative symptom improvement after adenotonsillecto-
Snoring 7.931.62 6.122.43 0.032 my. (A) Mouth breathing, (B) snoring, (C) nasal obstruction, (D) rhi-
Nasal obstruction 8.521.61 6.422.52 0.029 norrhea, (E) itching, and (F) sneezing. Both allergic rhinitis (AR)
Rhinorrhea 7.832.52 5.312.85 0.027 group and control group showed improvement of symptoms in
Itching 7.813.31 1.522.13 0.003
mouth breathing, snoring, nasal obstruction, and rhinorrhea. Control
group showed significantly greater improvement in symptoms ex-
Sneezing 7.323.24 1.101.53 0.003
cept itching and sneezing than AR group. VAS, visual analogue
AR, allergic rhinitis; VAS, visual analogue scale; NS, nonsignificant. scale. *P <0.05. **P <0.01.
page 4 of 6 Clinical and Experimental Otorhinolaryngology

I II III IV I II III IV
10 * ** 10 * ** 10 10

VAS

VAS
VAS

VAS
5 5 5 5

0 0 0 0
A B AR group Control group A AR group Control group
B
AR group Control group AR group Control group

10 ** ** 10 10 10

VAS

VAS
5 5
VAS
VAS

5 5

0 0 0 0
C D AR group Control group
C AR group Control group D
AR group Control group AR group Control group

10 10 10 10
VAS

VAS

VAS

VAS
5 5 5 5

0 0 0 E 0 F
AR group Control group E AR group Control group F AR group Control group AR group Control group

Fig. 2. The dependency of symptom changes on the Friedman tonsil Fig. 3. The dependency of symptom changes on the adenoid grade.
grade. (A) Mouth breathing, (B) snoring, (C) nasal obstruction, (D) (A) Mouth breathing, (B) snoring, (C) nasal obstruction, (D) rhinor-
rhinorrhea, (E) itching, and (F) sneezing. Obstructive symptoms like rhea, (E) itching, and (F) sneezing. All the symptoms did not show
mouth breathing and snoring were significantly dependent on Fried- any dependency on adenoid grade. VAS, visual analogue scale.
man tonsil grade in both groups. Nasal obstruction also showed de-
pendency on Friedman tonsil grade in both groups, however rhinor-
rhea, itching, and sneezing did not show any dependency on Fried- DISCUSSION
man tonsil grade. VAS, visual analogue scale. *P <0.05. **P <0.01.
Adenotonsillectomy is the primary therapeutic approach for up-
grade (all P<0.05) (Fig. 2). The dependency on the Friedman per airway problems in children [9,10]. It could resolve upper
tonsil grade was more prominent in control group when com- airway obstruction in most cases. However, it does not always
pared with that of AR group. Postoperative improvement of na- lead to complete remission of the upper airway obstructive
sal obstruction was also dependent on Friedman tonsil grade in symptoms and residual mild airway problems were found after
both groups. However, improvement in rhinorrhea, itching, and adenotonsillectomy in more than one third of the patients
sneezing was not dependent on the tonsil grade, as expected. [11,12]. These findings imply that other factors could be respon-
However, the degree of adenoid enlargement did not affect sible for the postoperative remained symptoms.
the improvement in either obstructive or nonobstructive symp- Among several factors other than adenotonsillar hypertrophy,
toms after surgery (Fig. 3). AR was considered to influence upper airway obstruction signif-
icantly [13], and previous studies showed that by the age of six,
Analysis of association between symptom and variable factor 42% of the children had AR [14]. Considering the higher preva-
Lastly, logistic regression analysis was performed to investigate lence of AR in children, the exact changes in symptoms after
the associated factors that determine the pre- and postoperative adenotonsillectomy should be analyzed according to the pres-
symptoms (mouth breathing, snoring, nasal obstruction, and rhi- ence of AR.
norrhea). Multiple variables such as sex, asthma, AR, tonsil In this study, we showed that patients with AR had more se-
grade, and adenoid grade were used. Preoperative obstructive vere obstructive and rhinitis symptoms preoperatively and even
symptoms such as mouth breathing and snoring were associated after adenotonsillectomy. In addition, although adenotonsillec-
mainly with the Friedman tonsil grade; However, postoperative tomy had improved symptoms in both AR and control groups,
symptoms were significantly associated with AR (P<0.001). Na- the degrees of symptom improvement were significantly lower
sal obstruction was associated with both AR and Friedman tonsil in AR group in most of the symptoms except itching and sneez-
grade before surgery, and significantly associated with AR after ing. Therefore, these findings suggest the importance of AR man-
surgery (P<0.001), Rhinorrhea was associated with AR before agement in patients with AR even after adenotonsillectomy.
and after surgery (Table 3). AR was known to be an important factor associated with ab-
errant facial growth. Remaining nasal obstruction as well as ob-
structive symptoms can cause the craniofacial morphometric
 Lee DJ et al. The Impact of Allergic Rhinitis After Adenotonsillectomy page 5 of 6

Table 3. Association of symptoms with multiple variables with logistic regression analysis
Preoperative Postoperative
Variable
95% CI P-value 95% CI P-value
Mouth breathing
Sex 1.06 0.542.08 0.852 1.48 0.752.93 0.252
AR 0.72 0.371.41 0.341 23.06 9.5155.88 <0.001*
Asthma 1.22 0.188.18 0.833 1.16 0.216.42 0.863
Tonsil grade 6.31 2.5915.38 <0.001* 0.63 0.271.46 0.282
Adenoid grade 0.66 0.341.27 0.212 0.84 0.421.67 0.631
Snoring
Sex 1.21 0.432.18 0.732 1.02 0.492.12 0.261
AR 0.91 0.271.72 0.291 11.02 3.2121.8 <0.001*
Asthma 0.87 0.281.48 0.736 1.12 0.125.21 0.751
Tonsil grade 5.12 1.5911.21 <0.001* 0.52 0.121.53 0.232
Adenoid grade 0.71 0.321.15 0.323 0.71 0.351.40 0.325
Nasal obstruction
Sex 0.85 0.212.10 0.722 0.97 0.352.93 0.312
AR 4.12 0.3710.40 <0.001* 10.62 3.2121.48 <0.001*
Asthma 0.71 0.291.51 0.293 0.48 0.196.42 0.763
Tonsil grade 5.25 1.4913.28 <0.001* 0.71 0.273.46 0.425
Adenoid grade 0.59 0.211.37 0.515 0.56 0.126.48 0.236
Rhinorrhea
Sex 0.71 0.321.52 0.752 1.48 0.752.93 0.253
AR 9.21 2.2319.31 <0.001* 10.01 2.5321.11 <0.001*
Asthma 0.58 0.201.52 0.635 0.68 0.111.91 0.565
Tonsil grade 1.23 0.413.21 0.792 0.53 0.218.67 0.371
Adenoid grade 0.70 0.291.25 0.353 0.62 0.221.87 0.613
CI, confidence interval; AR, allergic rhinitis.
*P-values were statistically significant.

changes [15]. Nasal obstruction can also induce neuromuscular atively, suggesting the importance of AR as a risk factor for ob-
changes and these changes extend beyond the period of ob- structive symptoms such as snoring and mouth breathing even
struction and remain after the original stimulus for neuromuscu- after surgery. One previous study reported similar results that
lar changes has been removed [16]. Taken these findings togeth- AR was a risk factor that worsened the patients postoperative
er, they suggest that postoperative AR care should be performed symptoms, which is consistent with our data [17]. Other studies
to prevent complications of nasal obstruction. also showed the similar results that AR is an important factor in
We performed logistic regression analysis to investigate the maintaining the improvements after adenotonsillectomy. Recent
determining factor for each symptom (mouth breathing, snoring, studies have reported that sex, age, and adiposity do not affect
nasal obstruction, rhinorrhea) and multiple factors including sex, the postoperative symptoms after adenotonsillectomy, and that
asthma, AR, tonsil grade, and adenoid grade were analyzed as AR is the major risk factor for deterioration of symptoms in the
variables. long term after adenotonsillectomy [17,18].
Friedman tonsil grade was an important determining factor One thing that is noteworthy in our study is that the improve-
for obstructive symptoms such as mouth breathing or snoring ment of symptoms such as snoring and mouth breathing was
before surgery, which could be easily deducible by simple not associated with adenoid size. There might be some associa-
thought. The Friedman tonsil grade also affected nasal obstruc- tion between obstructive symptoms and adenoid size, however,
tion before adenotonsillectomy. Usually, tonsillar hypertrophy its statistical significance might not be high enough.
obstructs nasopharyngeal airway and results in mouth breathing Although our study showed the importance of AR after ade-
with the aid of adenoid hypertrophy. The nasopharyngeal ob- notonsillectomy, it has some limitations. First, this is a retrospec-
struction by tonsillar hypertrophy might affect the preoperative tive study with telephone survey rather than prospective study.
nasal obstruction symptom. Second, most of symptoms were answered by parents of the pa-
In contrast to Friedman tonsil grade, AR affected symptoms tients due to their young age. In addition, due to their young age
both before and after surgery. AR was associated with nasal ob- and poor cooperation, it was very difficult to follow up patients
struction and rhinorrhea preoperatively and postoperatively, and for long duration that telephone survey was performed. In tele-
was also associated with mouth breathing and snoring postoper- phone survey, the information given by respondents could be
page 6 of 6 Clinical and Experimental Otorhinolaryngology

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