Stability of respiratory symptoms in unlabelled wheezy illness and nocturnal cough

OBJECTIVE: To assess the natural history of respiratory symptoms not labelled as asthma in primary schoolchildren. DESIGN: Repeat questionnaire survey of subgroups identified from a previous questionnaire survey after a two year delay. SUBJECTS: The original population of 5321 Sheffield children aged 8-9 years yielded 4406 completed questionnaires in 1991(82.8%). After excluding children with a label of asthma, there were 370 children with current wheeze, 129 children with frequent nocturnal cough, and a random sample of 222 children with minor cough symptoms and 124 asymptomatic children. RESULTS: Response rates in the four groups were 233 (63.0%), 77 (59.7%), 160 (72.1%), and 90 (72.6%) respectively. Of those who initially wheezed, 114 (48.9%) had stopped wheezing and 42 (18.0%) had been labelled as having asthma. Those with more frequent wheezing episodes (p < 0.02) and a personal history of hay fever (p < 0.01) in 1991 were more likely to retain their wheezy symptoms. In the children with frequent nocturnal cough in 1991, 20.1% had developed wheezing, 42.9% had a reduced frequency of nocturnal coughing, and 14.2% had stopped coughing altogether two years later. One sixth had been labelled as having asthma. Children with nocturnal cough were more likely to develop wheezing if they had a family history of atopy (p = 0.02). Only 3.8% and 3.3% of those with minimal cough and no symptoms respectively in 1991 had developed wheeze by 1993 (1.9% and 1.0% labelled as asthma). CONCLUSIONS: Most unlabelled recurrent respiratory symptoms in 8-10 year olds tend to improve. Unlabelled children who have persistent symptoms have other features such as frequent wheezing attacks and a family or personal history of atopy. If a screening questionnaire were to be used to identify such children, a combination of questions should be employed.     

Relationship between respiratory symptoms and cough receptor sensitivity.

The relationship was studied between preschool and current respiratory symptoms and cough receptor sensitivity in children. Forty six white children aged 7 years were investigated. They were divided into three groups: (i) healthy children; (ii) children with a history of idiopathic cough; and (iii) children with a history of wheezing. Cough receptor sensitivity was assessed by the inhalation of serially increasing concentrations of nebulised citric acid. The concentration which first induced a cough was the cough threshold and was taken as a measure of cough receptor sensitivity. The cough threshold was unrelated to respiratory symptoms, bronchial responsiveness, parental smoking, and atopic status. A wide variation in cough threshold was seen. Although these results suggest that idiopathic cough is unrelated to cough receptor sensitivity as assessed by the citric acid cough threshold, it is unclear whether threshold measurements are an accurate reflection of receptor sensitivity.     

The spectral analysis of cough sounds in childhood respiratory illness

Cough is the commonest symptom of childhood respiratory disease and at times may be the predominant feature. The characteristic sound of the cough is often considered by the clinician as a useful diagnostic feature in such conditions as croup and whooping cough. This has prompted a closer study of the physical basis of the cough sounds and their relationship to the pathological processes in the airway.¹ Keleman et al. ² have demonstrated that there are at least three phases to any particular cough, that is, an initial burst due to air turbulence and tissue vibration, followed by a noisy phase, and the final vocalic burst as the glottis forcefully cuts off the air flow. These studies have led to the development of computer assisted methods of evaluation of cough.³ In turn, sound spectral analysis techniques, which have been used extensively to study lung sounds in asthma,⁴ have been applied to cough sounds.^5,6 A microcomputer-based system which allows rapid performance of such analyses has been devised and described recently.⁶     

Recurrent wheezy bronchitis and viral respiratory infections.

Fifty four patients aged from 1 to 6 years who had had recurrent attacks of wheezy bronchitis were prospectively followed up for three months to find out if there was an association between different viral respiratory infections and episodes of wheezing. Of the 115 episodes of upper or lower respiratory tract symptoms, virus or Mycoplasma pneumoniae infection were diagnosed in 52 (45%). Thirty four of rhinoviruses. The patients had an average of 2.1 episodes of respiratory tract symptoms the total mean (SD) duration of which was 30 (2) days of the 92 days that followed. Wheezing occurred during 76 (66%) of the 115 episodes and during a third of these the patient was admitted to hospital because of severe dyspnoea. Wheezing started a mean (SD) of 43 (7) hours after the first symptoms of respiratory infection and persisted for 3.8 (4.2) days in patients in whom virus infection was diagnosed. The incidence of wheezing was not associated with IgE mediated atopy, with positive virological tests, or with fever during virus infection, but was associated with parental smoking and more than one sibling.     

Atopy, bronchial responsiveness, and symptoms in wheezy 3 year olds.

Fifty children with at least one hospital admission for acute lower airway obstruction in the first 2.5 years of life were assessed at 3 years of age to determine the relationship between atopy, bronchial responsiveness, and the pattern of their symptoms. Bronchial responsiveness was measured by assessing the effect of inhaled metacholine, using the change in transcutaneous oxygen tension (PtCO2) as an indirect measure of response. Symptom patterns were defined by the number of wheezing episodes associated with colds and the presence or absence of cough or wheeze unrelated to viral infections. Forty per cent of the children were found to be atopic by skin prick test or history. In contrast to the situation found in older children and adults, the non-atopic children had significantly greater bronchial responsiveness (lower mean concentration of methacholine causing a 20% fall in PtCO2, the PC20) than the atopic children and significantly more of them had an onset of respiratory symptoms in the first year of life. Cough and wheeze in the absence of colds was more frequently found in the atopic children as was the use of continuous medication. However, the number of reported acute episodes of wheeze associated with colds was the same in the two groups. The findings of the study suggest that in this hospital based group of children, acute wheeze associated with colds in the first three years of life is independent of the finding of atopy and that bronchial responsiveness in this age group may have a different pathogenesis from that in older subjects.     

Effect of controlled release salbutamol on nocturnal cough in asthma.

Sixteen asthmatic children completed a double blind placebo controlled crossover study of controlled release salbutamol (CRS) to assess its efficacy in controlling night time cough. Children with asthma were enrolled into the study on the basis of a history of persistent cough confirmed by two overnight tape recordings at home. Outcome was measured by two overnight tapes on each medication. Other treatment was unaffected. There was no significant fall in cough counts on CRS. Median scores were 14.5 and 12.0 coughing episodes per night for CRS and placebo respectively. Mean overnight oxygen saturation was identical in both treatment periods but morning peak flow showed a trend towards improvement on CRS. Treatment with CRS does not have a significant effect in control of night cough although it may improve objective measurements of lung function.     

慢性咳嗽和喘息性疾病支气管肺泡灌洗液成分分析

目的 分析慢性咳嗽及喘息性疾病患儿支气管肺泡灌洗液成分。方法 应用免疫组化及ELISA方法，对哮喘（13例）、慢性咳嗽（10例）、婴幼儿喘鸣（8例）患儿和对照组（8例）共39例的支气管肺泡灌洗液进行细胞学分析及上清液IL－5浓度测定。结果 哮喘患儿支气管肺泡灌洗液嗜酸性粒细胞为3．0％（0．7％－8．8％），上皮细胞为3．0％（0．7％－12．0％），IL－5为1．7ng/L(0－16.0ng/L)，与慢性咳嗽组及婴幼儿喘鸣组相比，差异有非常显著意义（P＜0．01）；2例慢性咳嗽及3例婴幼喘鸣儿哮酸性粒细胞亦有异常增多，与组内其他必相比差异有显著意义；婴幼儿喘鸣组中性粒细胞明显增多。结论 哮喘患儿支气管肺泡灌洗液以嗜酸性粒细胞和上皮细胞明显增多为其特征性改变；慢性咳嗽患儿中有嗜酸性粒细胞异常增多者，应注意与哮喘鉴别；婴幼儿喘鸣者以中性粒细胞增多为著，抗哮喘治疗应慎重。     

Persistent nocturnal cough in childhood: a population based study.

A cross sectional epidemiological study was carried out to investigate the validity of persistent nocturnal cough (PNC) as an independent marker of childhood asthma. A screening questionnaire on respiratory symptoms was applied to 4003 children attending primary schools in Aberdeen, after which 799 symptomatic children and a random selection of 229 asymptomatic children were invited to attend for a diagnostic interview. Six hundred and seven (359 boys and 248 girls) symptomatic children and 135 asymptomatic children (57 boys and 78 girls) were selected from the screening questionnaires. Of 607 children with respiratory symptoms when interviewed, 27 (nine boys and 18 girls) had isolated PNC, and 97 (51 boys and 46 girls) had multiple symptoms (polysymptomatic asthma). The incidence of prematurity was highest in the group with PNC (19%). The prevalence of hay fever in children with PNC (11%) was similar to that of the asymptomatic group (15%) and less than that in the group with polysymptomatic asthma (41%). Eczema was twice as common in the PNC (19%) as in the asymptomatic children (10%) but only half as common in the polysymptomatic asthma group (35%). The prevalence of a parental history of hay fever was similar in all three groups. The prevalence of a parental history of eczema was similar in the PNC (7%) and asymptomatic (7%) groups but higher in the polysymptomatic asthma group (22%). The prevalence of a history of parental asthma was 30% in children with PNC, 13% in the asymptomatic group, and 42% in those with polysymptomatic asthma. The parents of three (11%) children with PNC were aware of a diagnosis of asthma; two of these children (7%) were on inhaled bronchodilator treatment and one (4%) was on a slow release theophylline preparation. Using a stepwise discriminant analysis procedure, in 18 (67%) children with PNC predicted membership was in the asymptomatic group and only nine (33%) children with PNC were grouped into the polysymptomatic asthma category. It is concluded that the clinical features of children with PNC resembled those of the asymptomatic population more closely than those of the polysymptomatic asthmatic population. In this age group PNC, in the absence of wheeze, shortness of breath or tightness in the chest, is likely to be a manifestation of atypical or hidden asthma in only a minority of cases.     

Relationship between rhinitis and nocturnal cough in school children

To cite this article: Higuchi O, Adachi Y, Itazawa T, Ito Y, Yoshida K, Ohya Y, Odajima H, Akasawa A, Miyawaki T. Relationship between rhinitis and nocturnal cough in school children. Pediatr Allergy Immunol 2012: 23: 562-566. ABSTRACT: Background: There is a complex relationship between rhinitis, asthma, and nocturnal cough. Methods: To evaluate whether rhinitis is an important risk factor for nocturnal cough and whether this effect is independent of asthma, we analyzed data collected using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire in a population-based nationwide survey. A child who had experienced a dry cough at night in the past 12?months in the absence of a cold was defined as having nocturnal cough. Results: After excluding 11,475 records with incomplete data, data from 136,506 children were analyzed. Nocturnal cough was significantly more prevalent in children with current rhinitis compared with children without rhinitis. The association between rhinitis and nocturnal cough was significant in children who had current asthma (adjusted OR [95% CI]: 2.26 [2.00-2.56] in children aged 6-7?yr, 1.90 [1.58-2.30] in those aged 13-14?yr, and 1.86 [1.60-2.19] in those aged 16-17?yr), and this association was even higher among children who had no asthma (adjusted OR [95% CI]: 3.65 [3.36-3.97] in children aged 6-7?yr, 3.05 [2.79-3.32] in those aged 13-14?yr, and 2.69 [2.51-2.88] in those aged 16-17?yr). Conclusions: There was a close association between rhinitis and nocturnal cough in young children through adolescents, and this effect was independent of asthma. Upper airways should be examined in children with nocturnal cough.     

Child assessment of dextromethorphan, diphenhydramine, and placebo for nocturnal cough due to upper respiratory infection

This study sought to investigate the efficacy of dextromethorphan (DM), diphenhydramine (DPH), and placebo (PL) for symptoms attributed to upper respiratory infections as determined by children, and to evaluate the concordance of perception of nocturnal symptoms between children and parents. A total of 37 children age 6 to 18 years of age were randomized in a double-masked fashion to receive a single bedtime dose of DM, DPH, or PL. Children found no significant difference in the effect of DM, DPH, or PL for any study outcome, and responses by parents and children were significantly correlated.     

Parental smoking and respiratory illness in infancy.

The relationship between parental smoking and respiratory illness in a birth cohort of 1180 one-year-old children was examined. Maternal smoking was associated with an increased incidence of lower respiratory illness but there was no statistically significant association between paternal smoking and lower respiratory illness. While children of mothers who smoked suffered more lower respiratory illnesses, their overall risk of respiratory infection was similar to that for children of nonsmoking mothers. The association between maternal smoking and infantile lower respiratory illness persisted when the child''s social background, perinatal history, and postnatal diet were taken into account. The findings favour the view that prolonged exposure to cigarette smoke predisposes infants to develop lower respiratory symptoms when they contract a respiratory infection.     

Effect of bronchodilators on respiratory resistance in infants and young children with bronchiolitis and wheezy bronchitis.

Rutter, N., Milner, A. D., and Hiller, E. J. (1975). Archives of Disease in Childhood, 50, 719. Effect of bronchodilators on respiratory resistance in infants and young children with bronchiolitis and wheezy bronchitis. Respiratory resistance was measured using a forced oscillation technique in 16 infants and young children with bronchiolitis and wheezy bronchitis. Measurements were made before and after administration of nebulized salbutamol or isoprenaline. No significant change in resistance was found.     

Gastro-oesophageal reflux and respiratory function in infants with respiratory symptoms.

This study aimed to define the incidence and severity of gastro-oesophageal reflux (GOR), as measured using 24 hour oesophageal pH monitoring, in 38 infants with recurrent respiratory symptoms and to relate these findings to measures of respiratory function. Twenty one infants had a pH under 4 for more than 5% of the time (one definition of abnormal GOR) and nine had GOR exceeding age related normal values. Maximum expiratory flow at functional residual capacity was reduced in 37 infants, airways resistance was raised in 19 infants, and thoracic gas volume was abnormal in 11 infants. There was no association between indices of GOR and measures of lung function whether assessed by correlation or by chi 2 analysis for normal versus abnormal values. However, individual infants appeared to have respiratory symptoms produced by GOR. This suggests that host responsiveness to GOR may be of greater relevance than the amount of GOR.     

Obesity and respiratory symptoms in primary school.

The association of weight for height and triceps skinfold with seven respiratory symptoms has been examined using logistic regression analysis in 7800 5 to 11 year old children (6200 in England and 1600 in Scotland). The results support the view that overweight children have a greater liability to some respiratory symptoms than other children. After allowing for age, sex, and social factors, significant (P less than 0.05) or borderline non-significant (P less than 0.1) positive associations were found between weight for height and the prevalence of bronchitis, ''chest ever wheezy'', and ''colds usually going to the chest''. This suggests that some respiratory illness can be reduced by preventing children from becoming overweight. If this is correct, more than nutritional gains can be achieved by implementing an effective health education programme on obesity.