Does the external nasal dilator strip help in sports activity? A systematic review and meta-analysis.

BACKGROUND: Numerous studies have shown that the external nasal dilator (END) increases the cross sectional area of the nasal valve, thereby reducing nasal resistance, transnasal inspiratory pressure, stabilizing the lateral nasal vestibule, and preventing its collapse during final inhalation. OBJECTIVES: Our objective was to carry out a systematic review of the literature and meta-analysis on the effects of the END during physical exercise. METHODS: After selecting articles in the PubMed, Cochrane Library and EMBASE databases, 624 studies were identified. However, after applying the inclusion and exclusion criteria, 19 articles were considered eligible for review. RESULTS: Those studies included in the meta-analysis, the maximal oxygen uptake (VO2max.) outcome was assessed in 168 participants in which no statistically significant difference was found, MD (95% CI) = 0.86 [- 0.43, 2.15], p = 0.19, and I2 = 0%. The heart rate (HR) outcome was assessed in 138 participants in which no statistically significant difference was found, MD (95% CI) = 0.02 [- 3.19, 3.22], p = 0.99, and I2 = 0%. The rating of perceived exertion (RPE) outcome was assessed in 92 participants in which no statistically significant difference was found, MD (95% CI) = - 0.12 [- 0.52, 0.28], p = 0.56, and I2 = 27%. CONCLUSIONS: The external nasal dilator strip showed no improvement in VO2max., HR and RPE outcomes in healthy individuals during exercise.

External nasal dilators: definition, background, and current uses.

Our goal was to revise the literature about external nasal dilators (ENDs) as to their definition, history, and current uses. We reviewed journals in the PubMed and MEDLINE databases. The current uses hereby presented and discussed are physical exercise, nasal congestion and sleep, snoring, pregnancy, cancer, and healthy individuals. Numerous studies have shown that ENDs increase the cross-sectional area of the nasal valve, reducing nasal resistance and transnasal inspiratory pressure and stabilizing the lateral nasal vestibule, avoiding its collapse during final inspiration. These effects also facilitate breathing and are beneficial to patients with nasal obstruction. Furthermore, END use is simple, noninvasive, painless, affordable, and bears minimum risk to the user. Most studies have limited sample size and are mainly focused on physical exercise. In conclusion, ENDs seem useful, so further studies involving potential effects on the performance of physical tests and improvements in sleep quality are necessary, especially in children and teenagers.

Evaluation of the effectiveness of the external nasal dilator strip in adolescent athletes: a randomized trial.

OBJECTIVES: Evaluate the cardio-respiratory capacity (VO2max.) and peak nasal inspiratory flow (PNIF) of healthy adolescent athletes with experimental and placebo external nasal dilator strips (ENDS). METHODS: 48 healthy adolescent athletes between the ages of 11 and 15 were evaluated and submitted to a cardio-respiratory 1000 m race in randomized order. The participants had peak nasal inspiratory flow (PNIF) values measured using the In-check-inspiratory flow meter. Dyspnea intensity was evaluated after a 1000 m test race using a labeled visual analog scale for dyspnea. RESULTS: In relation to VO2max., when the participants used the experimental ENDS, significantly higher means were noted than when the placebo was used (53.0 ± 4.2 mL/kg min(-1) and 51.2 ± 5.5 mL/kg min(-1), respectively) (p<0.05). In relation to PNIF, there was a statistically significant difference between the experimental and placebo ENDS result, that being, 123 ± 38 L/min and 116 ± 38 L/min, respectively (p<0.05). The dyspnea perceived by the participants was representatively lesser in the experimental ENDS condition compared to the placebo after the cardio-respiratory test (p<0.05). CONCLUSIONS: The results suggest that the ENDS improve maximal oxygen uptake, nasal patency and respiratory effort in healthy adolescent athletes after submaximal exercise.

Does BCG revaccination protect against the development of asthma?

Single BCG vaccination has been considered as a protective factor against asthma. However the effect of a second dose of BCG on the prevalence rate of asthma and asthma-allergic rhinitis-eczema comorbidity has not been studied exclusively among adolescents. In this ISAAC protocol-based cross sectional study we assessed the association between one single versus two doses of BCG among 2213 individuals aged 13-14 years old. We found no association between BCG revaccination and asthma, associated (OR = 0.68, 95% CI, 0.37-1.25) or not to allergic rhinitis and/or atopic eczema (OR = 1.07, 95% CI, 0.84-1.36).

Correlation between peak nasal inspiratory flow and peak expiratory flow in children and adolescents.

BACKGROUND: PEAK nasal inspiratory flow (PNIF) has been proposed as a simple method to evaluate nasal patency. Asthma and allergic rhinitis are commonly associated, and lower airway assessment can provide information concerning an objective interpretation of nasal function. AIMS: TO determine whether the PNIF is correlated with peak expiratory flow (PEF) in children and adolescents. METHODS AND RESULTS: Cross-sectional study carried out in healthy students randomly chosen in 14 public schools of the city of Belo Horizonte. PNIF and PEF were assessed for each subject as the following characteristics: gender, height, weight and age. We created a linear regression model to explain the PNIF, in which we included all the variables with a p value ≤ 0.25 in a univariate analysis, and to calculate the relationship between the maximum PNIF and maximum PEF by the Spearman correlation coefficient. In total, 297 healthy subjects, aged between six and eighteen years were evaluated. A positive and significant correlation between PNIF and PEF was found. CONCLUSIONS: PEF is predictive of PNIF. However, these measures evaluate two distinct segments of the airways and should be both obtained for a more precise assessment of airflow limitation.

Asthma and allergic rhinitis co-morbidity: a cross-sectional questionnaire study on adolescents aged 13-14 years.

AIMS: There is scarce epidemiological population-based data on the prevalence of asthma and allergic rhinitis (AR) co-morbidity in adolescents. The aim was to verify asthma and AR prevalence rates in order to emphasise asthma/AR co-morbidity. METHODS: Cross-sectional study using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire in adolescents aged 13-14 years, chosen randomly from public schools in Belo Horizonte, Brazil. RESULTS: A total of 3262 students were identified, 3083 (47.3% males) of whom completed the questionnaire (response rate 94.7%). The prevalence of symptoms related to asthma and AR co-morbidity was 8.4% (95% CI, 8.09-10.25). Among asthmatic adolescents, symptoms of AR were reported in 46.5% (95% CI, 42.60-52.08%). CONCLUSIONS: There is a high prevalence of adolescent asthma and AR co-morbidity in this area of Brazil. This co-morbidity is an important health issue that requires strategic application of primary health care facilities to achieve adequate control of both asthma and allergic rhinitis.

Nasal peak inspiratory flow and clinical score in children and adolescents with allergic rhinitis.

OBJECTIVE: To assess the correlation between nasal inspiratory peak flow (NIPF) and clinical scoring in patients with allergic rhinitis (AR). METHODS: A concurrent cohort study was carried out with 52 randomly selected patients aged six to 16 with moderate and severe persistent allergic rhinitis, and followed up for eight weeks. Measurements of NIPF and clinical score for AR were evaluated in a blinded manner. Correlations between NIPF and clinical scoring were obtained from linear regression using the Pearson's correlation coefficient (r). Significance level was p < 0.05. RESULTS: Moderate but statistically significant correlation between NIPF and clinical scoring was found (r = -0.44; p < or = 0.001) and nasal obstruction alone (r = -0.438; p < or = 0.001) were found. CONCLUSION: Results confirm data from studies conducted with adult patients that found weak correlation between allergic rhinitis symptoms and objective measurements of nasal obstruction as NIPF. NIPF and the clinical scoring are complementary tools to evaluate AR patients.