Exercise simultaneously increases nasal patency and bronchial obstruction in asthmatic children.

We found that simultaneous post-exercise increase in nasal patency and bronchial obstruction occurs only in children with atopic asthma, but not in sensitized children without asthma. In healthy children, the increase in nasal patency is accompanied by bronchial dilatation.

A follow-up study with acoustic rhinometry in children using nasal insulin.

Acoustic rhinometry is a widely used method especially suitable with children, since it has no side-effects and is easy to perform. The role of normal development of height or body surface area, and their effect on acoustic rhinometric results, is still a matter of debate. The purpose of this study was to determine the presence of any differences in rhinometric findings or nasal symptoms between children receiving daily administered nasal insulin or placebo. The usefulness of acoustic rhinometry for follow-up in children was also considered. A subcohort of 77 children taking part in the Type I Diabetes Prediction and Prevention Study was invited for a follow-up study with acoustic rhinometry. Children aged 1-12 years received daily either nasal insulin or a placebo. There was no difference between the two groups in nasal symptoms, minimal cross-sectional area or nasal volume measured with acoustic rhinometry. There was likewise no significant increase in rhinometric values during the two years of the follow-up. We conclude that acoustic rhinometry is a suitable method for objective follow-up in children. In a long-term follow-up the normal growth of the child should be taken into account.

Nasal insulin to prevent type 1 diabetes in children with HLA genotypes and autoantibodies conferring increased risk of disease: a double-blind, randomised controlled trial.

BACKGROUND: In mouse models of diabetes, prophylactic administration of insulin reduced incidence of the disease. We investigated whether administration of nasal insulin decreased the incidence of type 1 diabetes, in children with HLA genotypes and autoantibodies increasing the risk of the disease. METHODS: At three university hospitals in Turku, Oulu, and Tampere (Finland), we analysed cord blood samples of 116 720 consecutively born infants, and 3430 of their siblings, for the HLA-DQB1 susceptibility alleles for type 1 diabetes. 17 397 infants and 1613 siblings had increased genetic risk, of whom 11 225 and 1574, respectively, consented to screening of diabetes-associated autoantibodies at every 3-12 months. In a double-blind trial, we randomly assigned 224 infants and 40 siblings positive for two or more autoantibodies, in consecutive samples, to receive short-acting human insulin (1 unit/kg; n=115 and n=22) or placebo (n=109 and n=18) once a day intranasally. We used a restricted randomisation, stratified by site, with permuted blocks of size two. Primary endpoint was diagnosis of diabetes. Analysis was by intention to treat. The study was terminated early because insulin had no beneficial effect. This study is registered with ClinicalTrials.gov, number NCT00223613. FINDINGS: Median duration of the intervention was 1.8 years (range 0-9.7). Diabetes was diagnosed in 49 index children randomised to receive insulin, and in 47 randomised to placebo (hazard ratio [HR] 1.14; 95% CI 0.73-1.77). 42 and 38 of these children, respectively, continued treatment until diagnosis, with yearly rates of diabetes onset of 16.8% (95% CI 11.7-21.9) and 15.3% (10.5-20.2). Seven siblings were diagnosed with diabetes in the insulin group, versus six in the placebo group (HR 1.93; 0.56-6.77). In all randomised children, diabetes was diagnosed in 56 in the insulin group, and 53 in the placebo group (HR 0.98; 0.67-1.43, p=0.91). INTERPRETATION: In children with HLA-conferred susceptibility to diabetes, administration of nasal insulin, started soon after detection of autoantibodies, could not be shown to prevent or delay type 1 diabetes.

Physical exercise increases nasal patency in asthmatic and atopic preschool children.

BACKGROUND: Physical exercise causes a decrease in nasal mucosal congestion and hence an increase in nasal patency. This nasal response has been studied only in adults. A correlation between nasal obstruction and asthma or allergic rhinitis has been previously found. This study evaluates the influences of atopy and asthma on nasal patency and the changes in nasal patency induced by physical exercise in preschool children. METHODS: An 8-minute exercise challenge test was conducted in 31 children aged between 4.1 and 6.4 years: 13 children had asthma, 17 were atopic, and 13 had neither asthma nor atopy. Nasal patency was measured with acoustic rhinometry at baseline and 10 minutes after the exercise. RESULTS: At baseline, the total acoustic values were 17-25% larger in nonasthmatic children than in asthmatic children. Accordingly, the acoustic values in nonatopic children were 16-35% larger than in atopic children. After physical exercise, there was an overall increase in mean total nasal volume from 2.973 (SD = 0.647) to 3.405 cm(3) (SD = 0.705), indicating an improvement of 15% in nasal volume (p = 0.025). The increase in nasal patency was similar in asthmatic and nonasthmatic children, as well as in atopic and nonatopic children. CONCLUSION: A significant increase in total nasal volume after physical exercise was found in all preschool children. The minimal cross-sectional areas remained smaller in asthmatic and atopic children after exercise, indicating partly irreversible nasal mucosal congestion in these children.

Acoustic rhinometry in children: some practical aspects and influence of age and body surface area on results.

BACKGROUND: Since acoustic rhinometry was described there has been a lack of normal values for minimal cross-sectional area (MCA), especially for children. There has also been debate about factors influencing normal values. The purpose of this study was to find the normal values for children in a Finnish population and whether there is any correlation between age or body surface area (BSA) and MCA. METHODS: We measured 74 children (age, 1-12 years) with an acoustic rhinometer. The values of MCA were compared with age and BSA determined from height and weight. RESULTS: The mean of unilateral MCA was 0.225 cm2 (SD, 0.041). We found positive correlation between unilateral volume on the left side and age and between MCA from the right side and age or BSA as a constant predictor. As much as 28.4% of the measurements had to be rejected because of acoustic leakage between nostril and nosepiece. Only 6.8% had to be rejected because of a lack of cooperation. CONCLUSION: It is possible to find normal values for children. Acoustic rhinometry is well tolerated among children. The method is rapid, reliable and noninvasive, and minimal cooperation is required. The measurements must be performed in a standard way, and some important causes of errors must be kept in mind.