A simple asthma prediction tool for preschool children with wheeze or cough.

BACKGROUND: Many preschool children have wheeze or cough, but only some have asthma later. Existing prediction tools are difficult to apply in clinical practice or exhibit methodological weaknesses. OBJECTIVE: We sought to develop a simple and robust tool for predicting asthma at school age in preschool children with wheeze or cough. METHODS: From a population-based cohort in Leicestershire, United Kingdom, we included 1- to 3-year-old subjects seeing a doctor for wheeze or cough and assessed the prevalence of asthma 5 years later. We considered only noninvasive predictors that are easy to assess in primary care: demographic and perinatal data, eczema, upper and lower respiratory tract symptoms, and family history of atopy. We developed a model using logistic regression, avoided overfitting with the least absolute shrinkage and selection operator penalty, and then simplified it to a practical tool. We performed internal validation and assessed its predictive performance using the scaled Brier score and the area under the receiver operating characteristic curve. RESULTS: Of 1226 symptomatic children with follow-up information, 345 (28%) had asthma 5 years later. The tool consists of 10 predictors yielding a total score between 0 and 15: sex, age, wheeze without colds, wheeze frequency, activity disturbance, shortness of breath, exercise-related and aeroallergen-related wheeze/cough, eczema, and parental history of asthma/bronchitis. The scaled Brier scores for the internally validated model and tool were 0.20 and 0.16, and the areas under the receiver operating characteristic curves were 0.76 and 0.74, respectively. CONCLUSION: This tool represents a simple, low-cost, and noninvasive method to predict the risk of later asthma in symptomatic preschool children, which is ready to be tested in other populations.

Preterm birth, infant weight gain, and childhood asthma risk: a meta-analysis of 147,000 European children.

BACKGROUND: Preterm birth, low birth weight, and infant catch-up growth seem associated with an increased risk of respiratory diseases in later life, but individual studies showed conflicting results. OBJECTIVES: We performed an individual participant data meta-analysis for 147,252 children of 31 birth cohort studies to determine the associations of birth and infant growth characteristics with the risks of preschool wheezing (1-4 years) and school-age asthma (5-10 years). METHODS: First, we performed an adjusted 1-stage random-effect meta-analysis to assess the combined associations of gestational age, birth weight, and infant weight gain with childhood asthma. Second, we performed an adjusted 2-stage random-effect meta-analysis to assess the associations of preterm birth (gestational age <37 weeks) and low birth weight (<2500 g) with childhood asthma outcomes. RESULTS: Younger gestational age at birth and higher infant weight gain were independently associated with higher risks of preschool wheezing and school-age asthma (P < .05). The inverse associations of birth weight with childhood asthma were explained by gestational age at birth. Compared with term-born children with normal infant weight gain, we observed the highest risks of school-age asthma in children born preterm with high infant weight gain (odds ratio [OR], 4.47; 95% CI, 2.58-7.76). Preterm birth was positively associated with an increased risk of preschool wheezing (pooled odds ratio [pOR], 1.34; 95% CI, 1.25-1.43) and school-age asthma (pOR, 1.40; 95% CI, 1.18-1.67) independent of birth weight. Weaker effect estimates were observed for the associations of low birth weight adjusted for gestational age at birth with preschool wheezing (pOR, 1.10; 95% CI, 1.00-1.21) and school-age asthma (pOR, 1.13; 95% CI, 1.01-1.27). CONCLUSION: Younger gestational age at birth and higher infant weight gain were associated with childhood asthma outcomes. The associations of lower birth weight with childhood asthma were largely explained by gestational age at birth.

Breastfeeding and childhood asthma: systematic review and meta-analysis.

Asthma and wheezing disorders are common chronic health problems in childhood. Breastfeeding provides health benefits, but it is not known whether or how breastfeeding decreases the risk of developing asthma. We performed a systematic review and meta-analysis of studies published between 1983 and 2012 on breastfeeding and asthma in children from the general population. We searched the PubMed and Embase databases for cohort, cross-sectional, and case-control studies. We grouped the outcomes into asthma ever, recent asthma, or recent wheezing illness (recent asthma or recent wheeze). Using random-effects meta-analyses, we estimated pooled odds ratios of the association of breastfeeding with the risk for each of these outcomes. We performed meta-regression and stratified meta-analyses. We included 117 of 1,464 titles identified by our search. The pooled odds ratios were 0.78 (95% confidence interval: 0.74, 0.84) for 75 studies analyzing "asthma ever," 0.76 (95% confidence interval: 0.67, 0.86) for 46 studies analyzing "recent asthma," and 0.81 (95% confidence interval: 0.76, 0.87) for 94 studies analyzing recent wheezing illness. After stratification by age, the strong protective association found at ages 0-2 years diminished over time. We found no evidence for differences by study design or study quality or between studies in Western and non-Western countries. A positive association of breastfeeding with reduced asthma/wheezing is supported by the combined evidence of existing studies.

Catch-up alveolarization in ex-preterm children: evidence from (3)He magnetic resonance.

RATIONALE: Histologic data from fatal cases suggest that extreme prematurity results in persisting alveolar damage. However, there is new evidence that human alveolarization might continue throughout childhood and could contribute to alveolar repair. OBJECTIVES: To examine whether alveolar damage in extreme-preterm survivors persists into late childhood, we compared alveolar dimensions between schoolchildren born term and preterm, using hyperpolarized helium-3 magnetic resonance. METHODS: We recruited schoolchildren aged 10-14 years stratified by gestational age at birth (weeks) to four groups: (1) term-born (37-42 wk; n = 61); (2) mild preterm (32-36 wk; n = 21); (3) extreme preterm (<32 wk, not oxygen dependent at 4 wk; n = 19); and (4) extreme preterm with chronic lung disease (<32 wk and oxygen dependent beyond 4 wk; n = 18). We measured lung function using spirometry and plethysmography. Apparent diffusion coefficient, a surrogate for average alveolar dimensions, was measured by helium-3 magnetic resonance. MEASUREMENTS AND MAIN RESULTS: The two extreme preterm groups had a lower FEV1 (P = 0.017) compared with term-born and mild preterm children. Apparent diffusion coefficient was 0.092 cm(2)/second (95% confidence interval, 0.089-0.095) in the term group. Corresponding values were 0.096 (0.091-0.101), 0.090 (0085-0.095), and 0.089 (0.083-0.094) in the mild preterm and two extreme preterm groups, respectively, implying comparable alveolar dimensions across all groups. Results did not change after controlling for anthropometric variables and potential confounders. CONCLUSIONS: Alveolar size at school age was similar in survivors of extreme prematurity and term-born children. Because extreme preterm birth is associated with deranged alveolar structure in infancy, the most likely explanation for our finding is catch-up alveolarization.

Breastfeeding and lung function at school age: does maternal asthma modify the effect?

RATIONALE: The evidence for an effect of breastfeeding on lung function is conflicting, in particular whether the effect is modified by maternal asthma. OBJECTIVES: To explore the association between breastfeeding and school-age lung function. METHODS: In the Leicestershire Cohort Studies we assessed duration of breastfeeding (not breastfed, ≤3 months, 4-6 months, and >6 months), other exposures, and respiratory symptoms by repeated questionnaires. Post-bronchodilator FVC, FEV(1), peak expiratory flow (PEF), forced midexpiratory flow (FEF(50)), and skin prick tests were measured at age 12 years. We performed multivariable linear regression and tested potential causal pathways (N = 1,458). MEASUREMENTS AND MAIN RESULTS: In the entire sample, FEF(50) was higher by 130 and 164 ml in children breastfed for 4 to 6 months and longer than 6 months, respectively, compared with those not breastfed (P = 0.048 and 0.041), with larger effects if the mother had asthma. FVC and FEV(1) were associated with breastfeeding only in children of mothers with asthma (P for interaction, 0.018 and 0.008): FVC was increased by 123 and 164 ml for those breastfed 4 to 6 months or longer than 6 months, respectively (P = 0.177 and 0.040) and FEV(1) was increased by 148 and 167 ml, respectively (P = 0.050 and 0.016). Results were unchanged after adjustment for respiratory infections in infancy and asthma and atopy in the child. CONCLUSIONS: In this cohort, breastfeeding for more than 4 months was associated with increased FEF(50) and, in children of mothers with asthma, with increased FEV(1) and FVC. It seems that the effect is not mediated via avoidance of early infections or atopy but rather through a direct effect on lung growth.

Relation of achievement motives, satisfaction with life, happiness and oral health in Romanian university students.

PURPOSE: The objective of the present study was to investigate whether achievement motives, satisfaction with life and happiness are associated with oral health behaviour and perceived gingival status. METHODS: The present study sample consisted of 178 first-year medical students. The questionnaire included information about sociodemographic factors, behavioural variables, perceived oral health status, achievement motives (hope of success and fear of failure), satisfaction with life and subjective happiness scales. RESULTS: It was observed that individuals who presented higher values of satisfaction with life and happiness rated their gingival status as being very good/excellent and that individuals who presented higher values of hope of success reported to brush frequently. When the oral health behaviour was analysed, it was revealed that persons who brushed their teeth more than twice a day reported higher values of hope of success when compared with individuals who reported their toothbrushing frequency to be once a day or less. It was also revealed that persons who visited their clinician for check-ups reported higher values of subjective happiness. Multiple linear regression analyses showed that stress in everyday life and hope of success were positively associated with the toothbrushing frequency and that satisfaction with life was positively associated with the gingival health status. CONCLUSIONS: Hope of success and satisfaction with life should be considered as predictors of good oral health behaviour/status.

Self-control and self-confidence: their relationship to self-rated oral health status and behaviours.

PURPOSE: The aim of this study was to examine the relationship between self-control and self-confidence, and students' self-rated oral health and oral-health-related behaviours. MATERIALS AND METHODS: The present study sample consisted of 178 first-year medical students. The questionnaire that was used in this study included information about sociodemographic factors, behavioural factors, self-reported oral health status, self-control and self-confidence. RESULTS: The results showed that mean levels of self-confidence in individuals with current extracted teeth and with poor/very poor perceived gingival condition were statistically significant and lower than those with no current extracted teeth and with self-rated excellent gingival health (P < 0.05). Also participants with self-reported gingival bleeding showed lower values of self-control compared with those with healthy non-bleeding gingiva (P < 0.05). When oral health behaviour was evaluated, it was shown that students with higher scores of self-control were more likely to use everyday mouthrinses (P < 0.05). The multiple linear regression analyses showed, for self-rated oral and gingival health status as dependent variable, a strong association with students' self-confidence level (P < 0.05). CONCLUSIONS: The results support the view that self-confidence is related with oral health status, and individuals with impaired oral and gingival health have a low self-confidence level.

Self-reported oral health status, oral health-related behaviours, resilience and hope in Romania.

PURPOSE: The aim of the present study was to investigate whether resilience, hope, perceived oral health status and oral health-related behaviours were associated. MATERIALS AND METHODS: The study sample consisted of 198 first-year medical students in Romania. The questionnaire included information about sociodemographic factors, behavioural variables, perceived oral health status, resilience and hope. RESULTS: Women had more resilience and 'personal competence' than men (P < 0.05). Resilience and hope were correlated with perceived dental health (P < 0.01). Perceived dental health was related to current non-treated caries, satisfaction with the appearance of one's own teeth, toothache last time and resilience (P < 0.001). Age, gender, current extracted teeth, perceived gingival bleeding and hope were not independent distinguishing variables after adjustment for internal heterogeneity. When oral health behaviours (toothbrushing, flossing, mouthrinse frequency and pattern of dental visit) were evaluated, it was demonstrated that flossing frequency was correlated with resilience and hope (P < 0.01). CONCLUSIONS: The results suggested that resilience and hope might be a psychosocial risk marker that influences perceived oral health status and behaviours.

Investigating the relationship between self-reported oral health status, oral health-related behaviours and self-consciousness in Romania.

PURPOSE: The aim of the present study was to investigate whether self-consciousness, self-reported oral health status and oral-health-related behaviours were associated. MATERIAL AND METHODS: The present study sample consisted of 253 first year medical students in Romania. The questionnaire included information about socio-demographic factors, behavioural variables, self-reported oral health status and three self-consciousness subscales (Private Self-Consciousness, Public Self-Consciousness, and Social Anxiety). RESULTS: Significant differences were found in Public Self-Consciousness and Social Anxiety according to several variables: anxiety, stress, depression and current non-treated caries. There were significant differences in Social Anxiety for the variables of gender, smoking, perceived dental health, self-reported gum bleeding and reason for dental visit (p < 0.05). A significant difference was found in Public Self-Consciousness for the reason for dental visits (p < 0.05). Total Self-Consciousness is correlated with anxiety, stress, depression, current non-treated caries, gingival bleeding and reason for dental visit. Oral health behaviours such as tooth brushing, flossing, mouth washing and last dental visit were not influenced by each of the self-consciousness subscales. CONCLUSIONS: The results suggest that self-consciousness might be a psychosocial risk marker that influences self-reported oral health status.

Instability of self-esteem and affective lability as determinants of self-reported oral health status and oral health-related behaviors.

AIM: The aim of the study was to examine the impact of the instability of self-esteem and affective lability on students' self-rated oral health and oral health-related behaviors. METHODS AND MATERIAL: The present study sample consisted of 178 first year medical students. A questionnaire was used to collect information about socio-demographic factors, behavioral factors, self-reported oral health status, the instability of self-esteem, and affective lability. RESULTS: Significant differences were found on the instability of self-esteem and affective lability on the following variables: gender, smoking, anxiety, depression, stress in everyday life, number of extracted teeth, and satisfaction with appearance of one's own teeth (Ps<0.05). The level of instability of self-esteem had a consistent association with the self-reported oral health status and satisfaction with appearance of teeth. The affective lability total score was a determinant of the number of extracted teeth, last toothache, self-rated gingival status, while anger was correlated with the number of current non-treated caries, extracted teeth, toothbrushing, and flossing frequency. CONCLUSIONS: The results indicate there is an increased risk for impaired dental health among subjects with instable self-esteem symptoms or symptoms of anger.

Prevalence of cough throughout childhood: A cohort study.

BACKGROUND: Cough in children is a common reason for medical consultations and affects quality of life. There are little population-based data on the epidemiology of recurrent cough in children and how this varies by age and sex, or between children with and without wheeze. We determined the prevalence of cough throughout childhood, comparing several standardised cough questions. We did this for the entire population and separately for girls and boys, and for children with and without wheeze. METHODS: In a population-based prospective cohort from Leicestershire, UK, we assessed prevalence of cough with repeated questionnaires from early childhood to adolescence. We asked whether the child usually coughed more than other children, with or without colds, had night-time cough or cough triggered by various factors (triggers, related to increased breathing effort, allergic or food triggers). We calculated prevalence from age 1 to 18 years using generalised estimating equations for all children, and for children with and without wheeze. RESULTS: Of 7670 children, 10% (95% CI 10-11%) coughed more than other children, 69% (69-70%) coughed usually with a cold, 34% to 55% age-dependently coughed without colds, and 25% (25-26%) had night-time cough. Prevalence of coughing more than peers, with colds, at night, and triggered by laughter varied little throughout childhood, while cough without colds and cough triggered by exercise, house dust or pollen became more frequent with age. Cough was more common in boys than in girls in the first decade of life, differences got smaller in early teens and reversed after the age of 14 years. All symptoms were more frequent in children with wheeze. CONCLUSIONS: Prevalence of cough in children varies with age, sex and with the questions used to assess it, suggesting that comparisons between studies are only valid for similar questions and age groups.

Breastfeeding, lung volumes and alveolar size at school-age.

BACKGROUND: Previous studies found larger lung volumes at school-age in formerly breastfed children, with some studies suggesting an effect modification by maternal asthma. We wanted to explore this further in children who had undergone extensive lung function testing. The current study aimed to assess whether breastfeeding was associated with larger lung volumes and, if so, whether all compartments were affected. We also assessed association of breastfeeding with apparent diffusion coefficient (ADC), which measures freedom of gas diffusion in alveolar-acinar compartments and is a surrogate of alveolar dimensions. Additionally, we assessed whether these effects were modified by maternal asthma. METHODS: We analysed data from 111 children and young adults aged 11-21 years, who had participated in detailed lung function testing, including spirometry, plethysmography and measurement of ADC of (3)Helium ((3)He) by MR. Information on breastfeeding came from questionnaires applied in early childhood (age 1-4 years). We determined the association between breastfeeding and these measurements using linear regression, controlling for potential confounders. RESULTS: We did not find significant evidence for an association between duration of breastfeeding and lung volumes or alveolar dimensions in the entire sample. In breastfed children of mothers with asthma, we observed larger lung volumes and larger average alveolar size than in non-breastfed children, but the differences did not reach significance levels. CONCLUSIONS: Confirmation of effects of breastfeeding on lung volumes would have important implications for public health. Further investigations with larger sample sizes are warranted.

Copy number variation of the beta-defensin genes in europeans: no supporting evidence for association with lung function, chronic obstructive pulmonary disease or asthma.

Lung function measures are heritable, predict mortality and are relevant in diagnosis of chronic obstructive pulmonary disease (COPD). COPD and asthma are diseases of the airways with major public health impacts and each have a heritable component. Genome-wide association studies of SNPs have revealed novel genetic associations with both diseases but only account for a small proportion of the heritability. Complex copy number variation may account for some of the missing heritability. A well-characterised genomic region of complex copy number variation contains beta-defensin genes (DEFB103, DEFB104 and DEFB4), which have a role in the innate immune response. Previous studies have implicated these and related genes as being associated with asthma or COPD. We hypothesised that copy number variation of these genes may play a role in lung function in the general population and in COPD and asthma risk. We undertook copy number typing of this locus in 1149 adult and 689 children using a paralogue ratio test and investigated association with COPD, asthma and lung function. Replication of findings was assessed in a larger independent sample of COPD cases and smoking controls. We found evidence for an association of beta-defensin copy number with COPD in the adult cohort (OR = 1.4, 95%CI:1.02-1.92, P = 0.039) but this finding, and findings from a previous study, were not replicated in a larger follow-up sample(OR = 0.89, 95%CI:0.72-1.07, P = 0.217). No robust evidence of association with asthma in children was observed. We found no evidence for association between beta-defensin copy number and lung function in the general populations. Our findings suggest that previous reports of association of beta-defensin copy number with COPD should be viewed with caution. Suboptimal measurement of copy number can lead to spurious associations. Further beta-defensin copy number measurement in larger sample sizes of COPD cases and children with asthma are needed.

Etiology of ethnic differences in childhood spirometry.

OBJECTIVES: Age- and height-adjusted spirometric lung function of South Asian children is lower than those of white children. It is unclear whether this is purely genetic, or partly explained by the environment. In this study, we assessed whether cultural factors, socioeconomic status, intrauterine growth, environmental exposures, or a family and personal history of wheeze contribute to explaining the ethnic differences in spirometric lung function. METHODS: We studied children aged 9 to 14 years from a population-based cohort, including 1088 white children and 275 UK-born South Asians. Log-transformed spirometric data were analyzed using multiple linear regressions, adjusting for anthropometric factors. Five different additional models adjusted for (1) cultural factors, (2) indicators of socioeconomic status, (3) perinatal data reflecting intrauterine growth, (4) environmental exposures, and (5) personal and family history of wheeze. RESULTS: Height- and gender-adjusted forced vital capacity (FVC) and forced expired volume in 1 second (FEV1) were lower in South Asian than white children (relative difference -11% and -9% respectively, P < .001), but PEF and FEF50 were similar (P ≥ .5). FEV1/FVC was higher in South Asians (1.8%, P < .001). These differences remained largely unchanged in all 5 alternative models. CONCLUSIONS: Our study confirmed important differences in lung volumes between South Asian and white children. These were not attenuated after adjustment for cultural and socioeconomic factors and intrauterine growth, neither were they explained by differences in environmental exposures nor a personal or family history of wheeze. This suggests that differences in lung function may be mainly genetic in origin. The implication is that ethnicity-specific predicted values remain important specifically for South Asian children.