International Journal of Contemporary Pediatrics Krithika AP et al. Int J Contemp Pediatr. 2018 Nov;5(6):2278-2283 http://www.ijpediatrics.com pISSN 2349-3283 | eISSN 2349-3291 DOI: http://dx.doi.org/10.18203 /2349-3291.ijcp20184296 Original Research Article Peak expiratory flow rate assessment to screen for asthma in children with allergic rhinitis Krithika A. P.*, Arunkumar T., Sundari S. Department of Paediatrics, Sree Balaji Medical College and Hospital, Tamil Nadu, India Received: 02 September 2018 Accepted: 27 September 2018 *Correspondence: Dr. Krithika A. P., E-mail: [email protected] Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT Background: Allergic rhinitis is a common disease affecting around 10-25% of the population worldwide. There is a temporal relationship between the onset of allergic rhinitis and asthma and the ‘unified airway hypothesis’ explains this. Many researchers have demonstrated bronchial hyper-responsiveness prior to onset of asthma symptoms further validating this hypothesis. Further many studies favour treating allergic rhinitis may prevent the onset of asthma. So, detecting allergic rhinitis earlier and treating it adequately is of vital importance. The aims and objectives of this study is to identify bronchial hyper responsiveness in children with allergic rhinitis, prior to the onset of asthmatic symptoms, by measuring PEFR and its clinical correlates. Methods: A prospective observational study was conducted in Department of Paediatrics in Sree Balaji Medical College and Hospital. Inclusion and Exclusion Criteria were defined, and the study was conducted on a total of 85 children. After taking informed consent from parents, the children coming under the study population were analyzed for their baseline characteristics and PEFR is measured using a low reading Mini Wright peak flow meter and compared with mean value of south Indian children using the formula, PEFR= {(HEIGHT IN CM-100) X5} +100. Results: The mean PEFR as expressed in percentage of expected PEFR is 77.28% in males and 83.34% in females. The mean percentage of expressed PEFR does not vary significantly between different age groups. Of the 85 children,48(56.5%) have mild intermittent allergic rhinitis,28(32.9%) have mild persistent allergic rhinitis,5(5.9%) have moderate-severe intermittent allergic rhinitis and 4(4.7%) have moderate-severe persistent allergic rhinitis. There were 37(43.5%) blockers (with predominant nose block) and 48(56.5%) runners (with predominant rhinorrhea). Conclusions: PEFR is abnormal in 41.2% of children with allergic rhinitis. PEFR reduces linearly as the severity of allergic rhinitis increases. PEFR decreases as the number of cardinal symptoms increases. PEFR increases significantly after treatment of allergic rhinitis alone. Keywords: Allergic rhinitis, Asthma screening, Peak expiratory flow rate INTRODUCTION associated to asthma.1 These studies have demonstrated that impairment and dysfunction of the upper and lower Allergic rhinitis represents a global health problem airways frequently occur together and appear to share affecting 3-40% of population worldwide. It is a chronic common risk factors such as atopy common inflammatory disease induced by an IgE-mediated inflammatory mediators common defence mechanisms reaction in response to allergen exposure in the nasal and common nervous control.2-5 Allergic rhinitis mucosa. It is now clear from a large number of cross developing in the first years of life is an early sectional studies that allergic rhinitis is strongly manifestation of an atopic predisposition, which may be International Journal of Contemporary Pediatrics | November-December 2018 | Vol 5 | Issue 6 Page 2278 Krithika AP et al. Int J Contemp Pediatr. 2018 Nov;5(6):2278-2283 triggered by early environmental exposures. Allergic symptoms, Serum IgE levels and Absolute eosinophil rhinitis and that positive allergy skin tests are significant count. risk factors developing asthma. Patients with either perennial or seasonal allergic rhinitis are three times more The variation in PEFR among the different groups are likely to develop asthma than negative controls.4,5 analysed using the unpaired t test and one-way ANOVA test. The changes in PEFR after treatment of allergic Bronchial hyperresponsiveness (BHR) sometimes rhinitis is determined. The difference after treatment is referred to as airway hyperresponsiveness is the statistically analysed using paired t test. Statistical occurrence of excessive bronchoconstriction in response significance was taken as p<0.05. to a variety of inhaled stimuli, both chemical and physical.6,7 BHR is regarded as a ‘hallmark’, a ‘defining RESULTS feature’ and the ‘most characteristic clinical feature’ of asthma. However, is often detected in atopic individuals, The inclusion criteria were met in 142 children among in patients with rhinitis but without pulmonary 1145 children. The prevalence of allergic rhinitis was symptoms. Several cross-sectional studies have shown 12.4%. 7 children were not included in this study as they that BHR was increased in subjects with allergic could not be trained to use the peak flow meter rhinitis.8-10 effectively.38 children (26.8%) were excluded as they have symptoms of asthma.7 children had tachypnea of At this point we can establish beyond doubt the existence other causes and could not be included in this study.3 of relationship between allergic rhinitis, asthma and children received oral steroids in the preceding 2 months Bronchial Hyperresponsiveness (BHR). Many and hence were excluded. So, the remaining 85 children researchers have demonstrated Bronchial Hyper were analysed. responsiveness prior to the onset of asthma symptoms, in support to our hypothesis.11,12 Of the 85 children 35 (41.2%) were females and 50 (58.8%) were males. Male to Female ratio is 1.4 to 1. The Many studies favour the view that treating allergic mean peak expiratory flow rate as expressed in rhinitis may prevent the onset of asthma.13,14 So detecting percentage of expected PEFR is 77.28% in males and and treating allergic rhinitis is of vital importance to 83.34% in females. Using unpaired t test the difference prevent future development of asthma. The methacholine between these values is not significant, 2 tailed p value is challenge test which is used in predominantly in studies 0.1085 as shown in Table 1. to determine Bronchial Hyper-Responsiveness is not available in many centres and not feasible for day to day Table 1: Gender and PEFR. use in clinic. The ease of performance and lack of invasiveness made the measurements of peak expiratory Gender Mean % of Number % flow rate, one of the most commonly used measures of distribution expected PEFR Bronchial Hyper-Responsiveness.15,16 Male 35 41.2 77.28% Female 50 58.8 83.34% This current study primarily aims at finding the 2 tailed p value=0.1085 usefulness of peak expiratory flow rate determination as 2 tailed p value=0.1085 an early marker of Bronchial Hyper-Responsiveness in children with allergic rhinitis and secondarily to More number of children are present in the 6 to 9 age determine the effect of treatment of allergic rhinitis on group. The mean percentage of Peak Expiratory flow rate Bronchial Hyper-Responsiveness. (PEFR) does not vary significantly between different age groups. METHODS This was analysed by one-way ANOVA and the p value It is a prospective observational study conducted from is 0.2 which is not significant as shown in Table 2. May 2017 to Feb 2018 in General outpatient department and allergy clinic outpatient department in Sree Balaji Table 2: Age Distribution and PEFR. Medical college and hospital. Age Group Mean % of expected No. All children coming under the study population after (in years) PEFR meeting inclusion and exclusion criteria were analyzed 5-9 57 80.6 for their baseline characteristics and PEFR is measured 10-13 24 81.2 using a low reading mini wright peak flow meter and >14 04 81.6 compared with mean value of south Indian children using p value by one-way ANOVA test is 0.20 the formula, PEFR= {(HEIGHT IN CM-100) X5} +100.17 At the end of the study, the results are tabulated. Of the 85 children, 48 (56.5%) have mild intermittent The PEFR values are grouped in various clinical allergic rhinitis, 28 (32.9%) have mild persistent allergic parameters like Age, Sex, ARIA classification, Cardinal International Journal of Contemporary Pediatrics | November-December 2018 | Vol 5 | Issue 6 Page 2279 Krithika AP et al. Int J Contemp Pediatr. 2018 Nov;5(6):2278-2283 rhinitis, 5 (5.9%) have moderate-severe intermittent PEFR (<80% of expected) also increases significantly as rhinitis and 4(4.7%) have moderate-severe persistent the severity of allergic rhinitis increases as shown in allergic rhinitis. The number of children with abnormal Table 3. Table 3: ARIA classification types, PEFR and severity of allergic rhinitis. Class >80% 60-80% <60% %abnormal Mean % of expected PEFR Mild intermittent 34 131 0 29.2 89 Mild persistent 15 10 3 46.4 79 Severe intermittent 1 1 3 80 63 Severe persistent 0 1 3 100 57 Total 50 25 10 41.2 P value by one-way ANOVA test is <0.0001 There were 37(43 %) blockers (with predominant nose increases with increasing severity with a p value of block) and 48(56.5%) runners (with predominant 0.0003, which is extremely significant. There is no rhinorrhea). 56 (65.9%) children had 2 cardinal correlation between serum IgE levels and mean symptoms ;16 (18%) had 3,10 (11.8%) had4 and 3 (3.5%) percentage of expected PEFR values (p value is 0.9) as had all the 5 cardinal symptoms.