Donna C. McCann

Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial

BACKGROUND We undertook a randomised, double-blinded, placebo-controlled, crossover trial to test whether intake of artificial food colour and additives (AFCA) affected childhood behaviour. METHODS 153 3-year-old and 144 8/9-year-old children were included in the study. The challenge drink contained sodium benzoate and one of two AFCA mixes (A or B) or a placebo mix. The main outcome measure was a global hyperactivity aggregate (GHA), based on aggregated z-scores of observed behaviours and ratings by teachers and parents, plus, for 8/9-year-old children, a computerised test of attention. This clinical trial is registered with Current Controlled Trials (registration number ISRCTN74481308). Analysis was per protocol. FINDINGS 16 3-year-old children and 14 8/9-year-old children did not complete the study, for reasons unrelated to childhood behaviour. Mix A had a significantly adverse effect compared with placebo in GHA for all 3-year-old children (effect size 0.20 [95% CI 0.01-0.39], p=0.044) but not mix B versus placebo. This result persisted when analysis was restricted to 3-year-old children who consumed more than 85% of juice and had no missing data (0.32 [0.05-0.60], p=0.02). 8/9-year-old children showed a significantly adverse effect when given mix A (0.12 [0.02-0.23], p=0.023) or mix B (0.17 [0.07-0.28], p=0.001) when analysis was restricted to those children consuming at least 85% of drinks with no missing data. INTERPRETATION Artificial colours or a sodium benzoate preservative (or both) in the diet result in increased hyperactivity in 3-year-old and 8/9-year-old children in the general population.

The role of acute and chronic stress in asthma attacks in children

BACKGROUND High levels of stress have been shown to predict the onset of asthma in children genetically at risk, and to correlate with higher asthma morbidity. Our study set out to examine whether stressful experiences actually provoke new exacerbations in children who already have asthma. METHODS A group of child patients with verified chronic asthma were prospectively followed up for 18 months. We used continuous monitoring of asthma by the use of diaries and daily peak-flow values, accompanied by repeated interview assessments of life events and long-term psychosocial experiences. The key measures included asthma exacerbations, severely negative life events, and chronic stressors. FINDINGS Severe events, both on their own and in conjunction with high chronic stress, significantly increased the risk of new asthma attacks. The effect of severe events without accompanying chronic stress involved a small delay; they had no effect within the first 2 weeks, but significantly increased the risk in the subsequent 4 weeks (odds ratio 1.71 [95% CI 1.04-2.82], p < or = 0.05 for weeks 2-4 and 2.17 [1.32-3.57], p < or = 0.01 for weeks 4-6). When severe events occurred against the backdrop of high chronic stress, the risk increased sharply and almost immediately within the first fortnight (2.98 [1.20-7.38], p < or = 0.05). The overall attack frequency was affected by several factors, some related to asthma and some to child characteristics. Female sex, higher baseline illness severity, three or more attacks within 6 months, autumn to winter season, and parental smoking were all related to increased risk of new exacerbations; social class and chronic stress were not. INTERPRETATION Severely negative life events increase the risk of childrens asthma attacks over the coming few weeks. This risk is magnified and brought forward in time if the childs life situation is also characterised by multiple chronic stressors.

Universal newborn screening for permanent childhood hearing impairment: an 8-year follow-up of a controlled trial

An 8-year follow-up study of the birth cohort of babies enrolled in the Wessex controlled trial of universal newborn screening (UNS) for permanent childhood hearing impairment (PCHI) was undertaken to establish whether UNS would increase the proportion of all true cases of PCHI in children aged 7-9 years who are referred early. The proportion referred before 6 months of age increased from 11 of 35 (31%) children with true PCHI born during periods without UNS to 23 of 31 (74%) born during periods with UNS (difference 43%, 95% CI 19-60). UNS leads to early referral of PCHI.

Asthma exacerbations in children immediately following stressful life events: a Cox's hierarchical regression

Background: A recent prospective study of children with asthma employing a within subject, over time analysis using dynamic logistic regression showed that severely negative life events significantly increased the risk of an acute exacerbation during the subsequent 6 week period. The timing of the maximum risk depended on the degree of chronic psychosocial stress also present. A hierarchical Cox regression analysis was undertaken to examine whether there were any immediate effects of negative life events in children without a background of high chronic stress. Methods: Sixty children with verified chronic asthma were followed prospectively for 18 months with continuous monitoring of asthma by daily symptom diaries and peak flow measurements, accompanied by repeated interview assessments of life events. The key outcome measures were asthma exacerbations and severely negative life events. Results: An immediate effect evident within the first 2 days following a severely negative life event increased the risk of a new asthma attack by a factor of 4.69 (p = 0.00). In the period 3–10 days after a severe event there was no increased risk of an asthma attack (p = 0.5). In addition to the immediate effect, an increased risk of 1.81 was found 5–7 weeks after a severe event (p = 0.002). This is consistent with earlier findings. There was a statistically significant variation due to unobserved factors in the incidence of asthma attacks between the children. Conclusion: The use of statistical methods capable of investigating short time lags showed that stressful life events significantly increase the risk of a new asthma attack immediately after the event; a more delayed increase in risk was also evident 5–7 weeks later.

Universal neonatal hearing screening moving from evidence to practice

Recent technological advances have made feasible universal newborn hearing screening and therefore early detection of permanent childhood hearing impairment. Over the past three years, new information has been published on whether early intervention is beneficial, the possibility of harm arising from newborn screening, and its cost. Dramatic progress has been made in the large scale implementation of universal screening in many parts of the western world.

The Relationship between Language Development and Behaviour Problems in Children with Hearing Loss.

BACKGROUND There are well-replicated findings that link poor development on a range of communication skills with increased behavioural problems. This paper examines this relationship in children with hearing loss. METHOD One hundred and twenty children with hearing loss (67 boys, 53 girls) and 63 hearing children (37 boys, 26 girls) with a mean age of 8 years from eight districts in Southern England were assessed for receptive and expressive language skills. The relationships between these measures and an aggregate of parent- and teacher-reported behaviour problems in the children were investigated. RESULTS Children with hearing loss had higher levels of behaviour problems compared to hearing children. Once the language abilities of children with hearing loss are taken into account, the negative effects of hearing loss on behaviour disappear. CONCLUSIONS Behaviour problems are found more commonly in children with hearing loss and the level of behaviour problems is highest amongst those children with hearing loss with the least developed language capabilities.

The economic costs of congenital bilateral permanent childhood hearing impairment.

OBJECTIVE. The objective of this study was to estimate the economic costs of bilateral permanent childhood hearing impairment (PCHI) in the preceding year of life for children aged 7 to 9 years. METHODS. A cost analysis was conducted by using a birth cohort of children born between 1992 and 1997 in 8 districts of Southern England, of which half had been born into populations exposed to universal newborn screening (UNS). Unit costs were applied to estimates of health, social, and broader resource use made by 120 hearing-impaired children and 63 children in a normally hearing comparison group. Associations between societal costs per child and severity of hearing impairment, language ability score, exposure to UNS, and age of confirmation were analyzed, including adjustment for potential confounders in a linear regression model. RESULTS. The mean societal cost in the preceding year of life at 7 to 9 years of age was £14092.5 for children with PCHI, compared with £4206.8 for the normally hearing children, a cost difference of £9885.7. After adjusting for severity and other potential confounders in a linear regression model, mean societal costs among children with PCHI were reduced by £2553 for each unit increase in the z score for receptive language. Using similar regression models, exposure to a program of UNS was associated with a smaller cost reduction of £2213.2, whereas costs were similar between children whose PCHI was confirmed at <9 or >9 months. CONCLUSIONS. The study provides rigorous evidence of the annual health, social, and broader societal cost of bilateral PCHI in the preceding year of life at 7 to 9 years of age and shows that it is related to its severity and has an inverse relationship with language abilities after adjustment for severity.

Language ability in children with permanent hearing impairment: the influence of early management and family participation

OBJECTIVE. The goal was to examine the relationships between management after confirmation, family participation, and speech and language outcomes in the same group of children with permanent childhood hearing impairment. METHODS. Speech, oral language, and nonverbal abilities, expressed as z scores and adjusted in a regression model, and Family Participation Rating Scale scores were assessed at a mean age of 7.9 years for 120 children with bilateral permanent childhood hearing impairment from a 1992–1997 United Kingdom birth cohort. Ages at institution of management and hearing aid fitting were obtained retrospectively from case notes. RESULTS. Compared with children managed later (>9 months), those managed early (≤9 months) had higher adjusted mean z scores for both receptive and expressive language, relative to nonverbal ability, but not for speech. Compared with children aided later, a smaller group of more-impaired children aided early did not have significantly higher scores for these outcomes. Family Participation Rating Scale scores showed significant positive correlations with language and speech intelligibility scores only for those with confirmation after 9 months and were highest for those with late confirmed, severe/profound, permanent childhood hearing impairment. CONCLUSIONS. Early management of permanent childhood hearing impairment results in improved language. Family participation is also an important factor in cases that are confirmed late, especially for children with severe or profound permanent childhood hearing impairment.

The role of histamine degradation gene polymorphisms in moderating the effects of food additives on children's ADHD symptoms.

OBJECTIVE Food additives can exacerbate ADHD symptoms and cause non-immunoglobulin E-dependent histamine release from circulating basophils. However, children vary in the extent to which their ADHD symptoms are exacerbated by the ingestion of food additives. The authors hypothesized that genetic polymorphisms affecting histamine degradation would explain the diversity of responses to additives. METHOD In a double-blind, placebo-controlled crossover trial, challenges involving two food color additive and sodium benzoate (preservative) mixtures in a fruit drink were administered to a general community sample of 3-year-old children (N = 153) and 8/9-year-old children (N = 144). An aggregate ADHD symptom measure (based on teacher and parent blind ratings of behavior, blind direct observation of behavior in the classroom, and--for 8/9-year-old children only--a computerized measure of attention) was the main outcome variable. RESULTS The adverse effect of food additives on ADHD symptoms was moderated by histamine degradation gene polymorphisms HNMT T939C and HNMT Thr105Ile in 3- and 8/9-year-old children and by a DAT1 polymorphism (short versus long) in 8/9-year-old children only. There was no evidence that polymorphisms in catecholamine genes COMT Val108Met, ADRA2A C1291G, and DRD4-rs7403703 moderated the effect on ADHD symptoms. CONCLUSIONS Histamine may mediate the effects of food additives on ADHD symptoms, and variations in genes influencing the action of histamine may explain the inconsistency between previous studies. Genes influencing a range of neurotransmitter systems and their interplay with environmental factors, such as diet, need to be examined to understand genetic influences on ADHD symptoms.

Barriers to, and facilitators of, parenting programmes for childhood behaviour problems: a qualitative synthesis of studies of parents’ and professionals’ perceptions

Disruptive behaviour problems (DBPs) during childhood exert a high burden on individuals, families and the community as a whole. Reducing this impact is a major public health priority. Early parenting interventions are recommended as valuable ways to target DBPs; however, low take-up of, and high drop-out rates from, these programmes seriously reduce their effectiveness. We present a review of published qualitative evidence relating to factors that block or facilitate access and engagement of parents with such programmes using a thematic synthesis approach. 12 papers presenting views of both parents and professionals met our inclusion and quality criteria. A large number of barriers were identified highlighting the array of challenges parents can face when considering accessing and engaging with treatment for their child with behavioural problems. Facilitating factors in this area were also identified. A series of recommendations were made with regard to raising awareness of programmes and recruiting parents, providing flexible and individually tailored support, delivering programmes through highly skilled, trained and knowledgeable therapists, and highlighting factors to consider when delivering group-based programmes. Clinical guidelines should address barriers and facilitators of engagement as well as basic efficacy of treatment approaches.