Behavioural susceptibility theory: the role of appetite in genetic susceptibility to obesity in early life.

Excess weight gained during the early years and, in particular, rapid weight gain in the first 2 years of life, are a major risk factors for adult obesity. The growing consensus is that childhood obesity develops from a complex interaction between genetic susceptibility and exposure to an 'obesogenic' environment. Behavioural susceptibility theory (BST) was developed to explain the nature of this gene-environment interaction, and why the 'obesogenic' environment does not affect all children equally. It hypothesizes that inherited variation in appetite, which is present from birth, determines why some infants and children overeat, and others do not, in response to environmental opportunity. That is, those who inherit genetic variants promoting an avid appetite are vulnerable to overeating and developing obesity, while those who are genetically predisposed to have a smaller appetite and lower interest in food are protected from obesity-or even at risk of being underweight. We review the breadth of research to-date that has contributed to the evidence base for BST, focusing on early life, and discuss implications and future directions for research and theory. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part I)'.

Emotional eating is learned not inherited in children, regardless of obesity risk.

BACKGROUND: Emotional over-eating (EOE) and emotional under-eating (EUE) are common behaviours that develop in early childhood and are hypothesised to play a role in weight status. Data from a British twin cohort demonstrated that environmental, rather than genetic, factors shape individual differences in both behaviours in early childhood. OBJECTIVE: The aim of this current study was to replicate this finding in a subsample (n = 398) of 4-year-old twins selected for high or low risk of obesity from another population-based cohort of British twins (the Twins Early Development Study). METHODS: Parental ratings of child EOE and EUE were analysed using genetic model fitting. RESULTS: Genetic influence was not significant, while shared environmental factors explained 71% (52-79%) of the variance in EOE and 77% (62-85%) in EUE. The two behaviours correlated positively (r = 0.53, 95% CI: 0.44, 0.61), and about two-thirds of the shared environmental factors influencing EOE and EUE were the same (rC  = 0.67, 95% CI: 0.51, 0.85). CONCLUSIONS: Emotional eating in childhood is shaped by the home family environment; parents are therefore promising intervention targets.

Long-term outcome of patients with argininosuccinate lyase deficiency diagnosed by newborn screening in Austria.

Twenty-three patients with late onset argininosuccinate lyase deficiency (ASLD) were identified during a 27-year period of newborn screening in Austria (1:95,600, 95% CI=1:68,036-1:162,531). One additional patient was identified outside the newborn screening with neonatal hyperammonemia. Long-term outcome data were available in 17 patients (median age 13 years) ascertained by newborn screening. Patients were treated with protein restricted diet and oral arginine supplementation during infancy and childhood. IQ was average/above average in 11 (65%), low average in 5 (29%), and in the mild intellectual disability range in 1 (6%) patients. Four patients had an abnormal EEG without evidence of clinical seizures and three had abnormal liver function tests and/or evidence of hepatic steatosis. Plasma citrulline levels were elevated in four patients. Plasma ammonia levels were within normal range prior and after a protein load in all patients. Seven different mutations were identified in the 16 alleles investigated. Four mutations were novel (p.E189G, p.R168C, p.R126P, and p.D423H). All mutations were associated with low argininosuccinate lyase activities (0-15%) in red blood cells. Newborn screening might be beneficial in the prevention of chronic neurologic and intellectual sequelae in late onset ASLD, but a proportion of benign variants might have contributed to the overall favorable outcome as well.

Investigating the impact of selection bias in dose-response analyses of preventive interventions.

This paper focuses on the impact of selection bias in the context of extended, community-based prevention trials that attempt to "unpack" intervention effects and analyze mechanisms of change. Relying on dose-response analyses as the most general form of such efforts, this study provides two examples of how selection bias can affect the estimation of treatment effects. In Example 1, we describe an actual intervention in which selection bias was believed to influence the dose-response relation of an adaptive component in a preventive intervention for young children with severe behavior problems. In Example 2, we conduct a series of Monte Carlo simulations to illustrate just how severely selection bias can affect estimates in a dose-response analysis when the factors that affect dose are not recorded. We also assess the extent to which selection bias is ameliorated by the use of pretreatment covariates. We examine the implications of these examples and review trial design, data collection, and data analysis factors that can reduce selection bias in efforts to understand how preventive interventions have the effects they do.

[ICD-10 diagnosis and quality of life. A pilot study of quality of life of children and adolescents with psychiatric disorders]. / ICD-10 Diagnostik und Lebensqualität. Pilotstudie zur Lebensqualität psychisch auffälliger Kinder und Jugendlicher.

OBJECTIVE: The present study examined whether the quality of life in children and adolescents with psychological disorders, as judged by the patients themselves and their mothers, differed according to the various ICD-10 diagnoses or the number of axes involved. METHODS: 151 children/adolescents and 125 mothers, referred consecutively to the clinic, completed the Inventory for Evaluation of Quality of Life in Children and Adolescents (Inventar zur Erfassung der Lebensqualität bei Kindern und Jugendlichen; ILK) by Mattejat et al. ICD-10 diagnoses were grouped for evaluation. RESULTS: No significant interaction between the five diagnostic axes and the several domains of quality of life was found. However, mothers of children and adolescents with attention deficit/hyperactivity disorders and/or conduct disorder more often tended to judge their children's quality of life as unsatisfactory in all domains, while the patients themselves did not. Thus, rather than the children themselves it seems to be the children's environment which considers "external disorders" to be distressing. CONCLUSIONS: The authors conclude that the quality of life as measured by the ILK cannot be captured by ICD-10 criteria. Apparently it is not so much the diagnosis itself but its subjective meaning that has the most essential impact on an individual's assessment of quality of life.

[The quality of life of chronically ill and psychiatrically disturbed children. Initial experiences with an inventory for assessing quality of life in children and adolescents]. / Zur Lebensqualität chronisch kranker und psychisch auffälliger Kinder. Erste Erfahrungen mit dem Inventar zur Erfassung der Lebensqualität bei Kindern und Jugendlichen (ILK).

OBJECTIVES: The assessment of the quality of life in chronically ill children as well as in children with emotional and behavioural problems. METHODS: A series of questionnaires (Inventar zur Erfassung der Lebensqualität bei Kindern und Jugendlichen, ILK, Mattejat et al.) were administered to 360 patients and 288 mothers at the Vienna University Children's Hospital. RESULTS: The results clearly show that patients with diabetes rate themselves as the most emotionally burdened and impaired in nearly all aspects of life: a picture which is confirmed by their mothers. Children and adolescents with psychological problems judge the initial problem as well as their social environment as significantly more burdensome. The respective mothers of these psychologically ill children feel that their impairments are greater in more aspects of life than do mothers of children who are chronically ill. The children generally pinpoint most of their difficulties in the areas "ability to occupy myself" and "psychological health". Among adolescents the most negative ratings occur in the areas "school", "psychological health", and "initial problem". CONCLUSIONS: The child's problems seem to weigh heavily upon the mothers. Interventions aimed at adolescents and mothers should be based on problem solving: supportive and anxiety-reducing approaches seem best suited for chronically ill children. Children with psychological problems primarily need problem-centred and practical support.

Increasing fruit and vegetable consumption among callers to the CIS: results from a randomized trial.

BACKGROUND: Results are reported from a large randomized trial designed to increase fruit and vegetable consumption among callers to the Cancer Information Service (CIS). METHODS: CIS callers assigned to the intervention group received a brief proactive educational intervention over the telephone at the end of usual service, with two follow-up mailouts. Key educational messages and print material derived from the NCI 5 A Day for Better Health program were provided to intervention subjects. Subjects were interviewed by telephone at both 4-week (n = 1,672) and 4-month (n = 1,286) follow-up. RESULTS: A single-item measure of fruit and vegetable consumption revealed a significant intervention effect of approximately 0.65 servings per day at 4-week follow-up (P < 0.001) and 0.41 servings per day at 4-month follow-up (P < 0.001). Using a seven-item food frequency measure that was also included in the 4-month interviews, a similar intervention effect of 0.34 servings per day was obtained (P = 0.006). The vast majority of CIS callers (88%) endorsed the strategy of providing 5 A Day information proactively. CONCLUSIONS: A brief educational intervention delivered to CIS callers at the end of usual service was associated with an increase in self-reported fruit and vegetable intake.

Proactive screening mammography counseling within the Cancer Information Service: results from a randomized trial.

In 1987, the Division of Cancer Prevention and Control, National Cancer Institute (NCI), funded a randomized trial of a proactive counseling protocol to promote screening mammography among age-eligible female callers to the Cancer Information Service (CIS). This protocol included interactive counseling by CIS counselors to help callers overcome barriers to screening mammography; this counseling was an extension of usual service and was combined with a 2-week follow-up mailout to reinforce the brief (6-minute) proactive telephone-counseling protocol. The screening-mammography counseling intervention was tested in two regional CIS offices using a randomized two-group design. Callers were randomly assigned to the intervention or control group based on the week of their call to the CIS (n = 1831 eligible female callers). Self-reported adherence to NCI screening-mammography guidelines was assessed from telephone interviews conducted at 12 months' follow-up (87% response rate). Among all CIS callers enrolled in this study, self-reported adherence to screening-mammography guidelines at 12 months' follow-up was 63.5%. The most frequently cited barriers to screening mammography reported by CIS callers were inconvenience/being too busy (52%), cost (36%), lack of physician referral (34%), no symptoms (34%), and fear of radiation (29%). A significant intervention effect on adherence behavior was found but only in one of the two test sites and only among CIS callers reporting total family income of $30,000 or more (odds ratio = 1.38, P = .04). The vast majority (90%) of CIS callers (both intervention and control subjects) endorsed the concept of proactive counseling by the CIS. The implications of these findings for the CIS and future research are discussed.