Towards a consistent definition of a significant delta troponin with z-scores: A way out of chaos?

Aims: We assessed the diagnostic performance of z-scores to define a significant delta cardiac troponin (cTn) in a cohort of patients with well-defined clinical outcomes. Methods: We calculated z-scores, which are dependent on the analytical precision and biological variation, to report changes in cTn. We compared the diagnostic performances of a relative delta (%Δ), actual delta (Δ), and z-scores in 762 emergency department patients with symptoms of suspected acute coronary syndrome. cTn was measured with sensitive cTnI (Beckman Coulter), highly sensitive cTnI (Abbott), and highly sensitive cTnT (Roche) assays. Results: Receiver operating characteristic analysis showed no statistically significant differences in the areas under the curve (AUC) of z-scores and Δ with both superior compared to %Δ for all three assays (p<0.001). The AUCs of z-scores measured with the Abbott hs-cTnI (0.955) and Roche hs-cTnT (0.922) assays were comparable to Beckman Coulter cTnI (0.933) (p=0.272 and 0.640, respectively). The individualized Δ cut-off values that were required to emulate a z-score of 1.96 were: Beckman Coulter cTnI 30 ng/l, Abbott hs-cTnI 20 ng/l, and Roche hs-cTnT 7 ng/l. Conclusions: z-scores allow the use of a single cut-off value at all cTn levels, for both cTnI and cTnT and for sensitive and highly sensitive assays, with comparable diagnostic performances. This strategy of reporting significant changes as z-scores may obviate the need for the empirical development of assay-specific cut-off rules to define significant troponin changes.

Twelve-month effectiveness of a parent-led, family-focused weight-management program for prepubertal children : a randomized, controlled trial

BACKGROUND Parenting-skills training may be an effective age-appropriate child behavior-modification strategy to assist parents in addressing childhood overweight. OBJECTIVE Our goal was to evaluate the relative effectiveness of parenting-skills training as a key strategy for the treatment of overweight children. DESIGN The design consisted of an assessor-blinded, randomized, controlled trial involving 111 (64% female) overweight, prepubertal children 6 to 9 years of age randomly assigned to parenting-skills training plus intensive lifestyle education, parenting-skills training alone, or a 12-month wait-listed control. Height, BMI, and waist-circumference z score and metabolic profile were assessed at baseline, 6 months, and 12 months (intention to treat). RESULTS After 12 months, the BMI z score was reduced by ∼10% with parenting-skills training plus intensive lifestyle education versus ∼5% with parenting-skills training alone or wait-listing for intervention. Waist-circumference z score fell over 12 months in both intervention groups but not in the control group. There was a significant gender effect, with greater reduction in BMI and waist-circumference z scores in boys compared with girls. CONCLUSION Parenting-skills training combined with promoting a healthy family lifestyle may be an effective approach to weight management in prepubertal children, particularly boys. Future studies should be powered to allow gender subanalysis.

The Eat Smart Study : a randomised controlled trial of a reduced carbohydrate versus a low fat diet for weight loss in obese adolescents

Background Despite the recognition of obesity in young people as a key health issue, there is limited evidence to inform health professionals regarding the most appropriate treatment options. The Eat Smart study aims to contribute to the knowledge base of effective dietary strategies for the clinical management of the obese adolescent and examine the cardiometablic effects of a reduced carbohydrate diet versus a low fat diet. Methods and design Eat Smart is a randomised controlled trial and aims to recruit 100 adolescents over a 2½ year period. Families will be invited to participate following referral by their health professional who has recommended weight management. Participants will be overweight as defined by a body mass index (BMI) greater than the 90th percentile, using CDC 2000 growth charts. An accredited 6-week psychological life skills program ‘FRIENDS for Life’, which is designed to provide behaviour change and coping skills will be undertaken prior to volunteers being randomised to group. The intervention arms include a structured reduced carbohydrate or a structured low fat dietary program based on an individualised energy prescription. The intervention will involve a series of dietetic appointments over 24 weeks. The control group will commence the dietary program of their choice after a 12 week period. Outcome measures will be assessed at baseline, week 12 and week 24. The primary outcome measure will be change in BMI z-score. A range of secondary outcome measures including body composition, lipid fractions, inflammatory markers, social and psychological measures will be measured. Discussion The chronic and difficult nature of treating the obese adolescent is increasingly recognised by clinicians and has highlighted the need for research aimed at providing effective intervention strategies, particularly for use in the tertiary setting. A structured reduced carbohydrate approach may provide a dietary pattern that some families will find more sustainable and effective than the conventional low fat dietary approach currently advocated. This study aims to investigate the acceptability and effectiveness of a structured reduced dietary carbohydrate intervention and will compare the outcomes of this approach with a structured low fat eating plan. Trial Registration: The protocol for this study is registered with the International Clinical Trials Registry (ISRCTN49438757).

Determinants of rapid weight gain during infancy: Baseline results from the NOURISH randomised controlled trial.

Background: Rapid weight gain in infancy is an important predictor of obesity in later childhood. Our aim was to determine which modifiable variables are associated with rapid weight gain in early life. Methods: Subjects were healthy infants enrolled in NOURISH, a randomised, controlled trial evaluating an intervention to promote positive early feeding practices. This analysis used the birth and baseline data for NOURISH. Birthweight was collected from hospital records and infants were also weighed at baseline assessment when they were aged 4-7 months and before randomisation. Infant feeding practices and demographic variables were collected from the mother using a self administered questionnaire. Rapid weight gain was defined as an increase in weight-for-age Z-score (using WHO standards) above 0.67 SD from birth to baseline assessment, which is interpreted clinically as crossing centile lines on a growth chart. Variables associated with rapid weight gain were evaluated using a multivariable logistic regression model. Results: Complete data were available for 612 infants (88% of the total sample recruited) with a mean (SD) age of 4.3 (1.0) months at baseline assessment. After adjusting for mother's age, smoking in pregnancy, BMI, and education and infant birthweight, age, gender and introduction of solid foods, the only two modifiable factors associated with rapid weight gain to attain statistical significance were formula feeding [OR=1.72 (95%CI 1.01-2.94), P= 0.047] and feeding on schedule [OR=2.29 (95%CI 1.14-4.61), P=0.020]. Male gender and lower birthweight were non-modifiable factors associated with rapid weight gain. Conclusions: This analysis supports the contention that there is an association between formula feeding, feeding to schedule and weight gain in the first months of life. Mechanisms may include the actual content of formula milk (e.g. higher protein intake) or differences in feeding styles, such as feeding to schedule, which increase the risk of overfeeding. Trial Registration: Australian Clinical Trials Registry ACTRN12608000056392

Parenting behaviours and maternal infant-feeding practices in first-time Australian mothers

Introduction: There is emerging evidence that parenting style and early feeding practices are associated with child intake, eating behaviours and weight status. The aim of this cross sectional study was to examine the relationships between general maternal parenting behaviour and feeding practices and beliefs. Methods: Participants were 421 first-time mothers of 9-22 week old healthy term infants (49% male, mean±sd age 19±4 weeks) enrolled in the NOURISH trial. At baseline mothers self-reported their parenting behaviours (self-efficacy, warmth, irritability) and infant-feeding beliefs using questions from the Longitudinal Study of Australian Children and the Infant Feeding Questionnaire (Baughcum, 2001), respectively. Multivariable regression analyses were used with feeding practices (four factors) as the dependent variables, Independent variables were maternal BMI, weight concern, age, education level perception of infant weight status, feeding mode (breast vs formula) and infant gender, age and weight gain z-score. Results: Parenting behaviours partly were associated with feeding beliefs (adjusted R2 =0.21-0.30). Higher maternal parenting self-efficacy was inversely associated with concerns that the baby would become underweight (p=0.006); become overweight (p<0.001); and lack of awareness of infant hunger/satiety cues (p<0.001). Higher maternal irritability was positively associated with lack of awareness of cues (p<0.05). Maternal warmth was not associated with any feeding beliefs. Infant weight- gain (from birth) z-score and age, maternal BMI and education level and mothers’ perception of infant weight status and feeding mode were covariates. Conclusions: These findings suggest strategies to improve early feeding practices need to be address broader parenting approaches, particularly self-efficacy and irritability.

The association between maternal infant feeding practices and child weight at 11-17 months in first-time Australian mothers

Introduction: Emerging evidence reveals that early feeding practices are associated with child food intake, eating behaviour and weight status. This cross-sectional analysis examined the association between maternal infant feeding practices/beliefs and child weight in Australian infants aged 11-17 months. Methods: Participants were 293 first-time mothers of healthy term infants (144 boys, mean age 14±1 months) enrolled in the NOURISH RCT. Mothers self-reported infant feeding practices and beliefs using the Infant Feeding Questionnaire (Baughcum, 2001). Anthropometric data were also measured at baseline (infants aged 4 months). Multiple regression analysis was used, adjusting for infant age, gender, birth weight, infant feeding mode (breast vs. formula), maternal perceptions of infant weight status, pre-pregnancy weight, weight concern, age and education. Results: The average child weight-for-age z-score (WAZ) was 0.62±0.83 (range:-1.56 to 2.94) and the mean change in WAZ (WAZ change) from 4 to 14 months was 0.62±0.69 (range:-1.50 to 2.76). Feeding practices/beliefs partly explained child WAZ (R2=0.28) and WAZ change (R2=0.13) in the adjusted models. While child weight status at 14 months was inversely associated with responsive feeding (e.g. baby feeds whenever she wants, feeding to stop baby being unsettled) (β=-0.104, p=0.06) and maternal concern about the child becoming underweight (β=-0.224, p<0.001), it was positively associated with mother’s concern about child overweight (β=0.197, p<0.05). Birth weight, infant’s age, maternal weight concern and perceiving her child as overweight were significant covariates. WAZ change was only significantly associated with responsive feeding (β=-0.147, p<0.05). Conclusion: Responsive feeding may be an important strategy to promote healthy child weight.

Associations between parenting behaviours and feeding beliefs of first-time Australian mothers in the NOURISH obesity prevention trial

Purpose: Parenting style and early feeding practices have been linked to child intake, eating behaviour and weight status. The purpose of this study was to examine associations between general maternal parenting behaviours and feeding beliefs in Australian mothers of 11-17 month-old children. Methods: This cross-sectional analysis included 223 first-time mothers and their children (49% male, mean age 14 [sd 1] months) enrolled in the control group of the NOURISH trial. Mothers self-reported their feeding beliefs and parenting behaviours (overprotection, irritability, warmth, autonomy-encouraging) using modified questions from the Infant Feeding Questionnaire (Baughcum, 2001) and the Longitudinal Study of Australian Children. Multiple regression analyses were conducted, using feeding beliefs (four factors) as dependent and parenting behaviours as independent variables while adjusting for child gender, age, weight-for-age z-score and maternal age, education level, feeding mode (breast vs. non-breast), and perception of own pre-pregnancy and child weight status. Results/Findings: Two of four parenting behaviours were significantly associated with feeding beliefs. Maternal warmth was inversely associated with concerns that the child would become underweight (β=-0.156, p=0.022) and positively associated with mothers’ awareness of child’s hunger/satiety cues (β=0.303, p<0.001). Mothers’ overprotection was positively associated with concerns that the child would become underweight (β=0.213, p=0.001); become overweight (β=0.174, p=0.005); and mother’s responsive feeding (β=0.135, p=0.057). Weight-for-age z-score, mothers’ perception of their child and own weight status, education, feeding mode, and child’s age were significant covariates. Conclusions: Feeding occurs within the broader parenting context. Improving early feeding beliefs and practices may require addressing mother’s approaches to parenting, especially warmth and overprotection.

Relationships between maternal feeding and child weight in younger Australian children – Findings from the NOURISH obesity prevention trial

Studies show that in 3-11 year-olds, parental feeding style is directly associated with child weight [1] and also moderates the association between feeding practices and weight [2]. This cross-sectional study aimed to examine these relationships in younger children. Data from 331 of 698 first-time mothers of healthy term children (151 boys, mean age 24±1 months) enrolled in the NOURISH RCT included (a) measured child weight, (b) self-reported feeding styles and controlling feeding practices, and (c) maternal and child covariates. ANCOVA compared mean child weight-for-age z-score (cWAZ) across 4 feeding styles. Regression examined the associations between cWAZ and 5 controlling feeding practices. Moderated multiple regression analysis was planned to examine effects of feeding style on relationships between feeding practices and cWAZ. Feeding style (indulgent = 38.6%, authoritarian = 35.8%, authoritative = 13.1%, uninvolved = 12.5%) was not independently associated with cWAZ. However, ’pressure to eat’ was negatively associated with cWAZ (�=-0.131, p<0.05) higher pressure associated with lower cWAZ. Given feeding style was not associated with cWAZ, moderation analysis was not performed. Contrary to findings in older children, cWAZ in 2-year-olds was not associated with maternal feeding style. However, the negative association between child weight and pressure feeding found in 6-11year-olds [2] appears to hold in toddlers. Educating mothers about potentially detrimental long-term effects of pressure feeding in early childhood, may be more practical and effective in promoting healthy weight than targeting the less concrete concept of feeding styles. References: [1] Hughes, Appetite, 2005;44:83-92. [2] Hennessy, Appetite, 2010;54:369-377.

Evaluation of an intervention to promote protective infant feeding practices to prevent childhood obesity : outcomes of the NOURISH RCT at 14 months of age and 6 months post the first of two intervention modules

OBJECTIVE: To evaluate a universal obesity prevention intervention, which commenced at infant age 4-6 months, using outcome data assessed 6-months after completion of the first of two intervention modules and 9 months from baseline. DESIGN: Randomised controlled trial of a community-based early feeding intervention. SUBJECTS AND METHODS: 698 first-time mothers (mean age 30±5 years) with healthy term infants (51% male) aged 4.3±1.0 months at baseline. Mothers and infants were randomly allocated to self-directed access to usual care or to attend two group education modules, each delivered over three months, that provided anticipatory guidance on early feeding practices. Outcome data reported here were assessed at infant age 13.7±1.3 months. Anthropometrics were expressed as z-scores (WHO reference). Rapid weight gain was defined as change in weight-for-age z-score (WAZ) > +0.67. Maternal feeding practices were assessed via self-administered questionnaire. RESULTS: There were no differences according to group allocation on key maternal and infant characteristics. At follow up (n=598 [86%]) the intervention group infants had lower BMIZ (0.42±0.85 vs 0.23±0.93, p=0.009) and infants in the control group were more likely to show rapid weight gain from baseline to follow up (OR=1.5 CI95%1.1-2.1, p=0.014). Mothers in the control group were more likely to report using non- responsive feeding practices that fail to respond to infant satiety cues such as encouraging eating by using food as a reward (15% vs 4%, p=0.001) or using games ( 67% vs 29%, p<0.001). CONCLUSIONS: These results provide early evidence that anticipatory guidance targeting the ‘when, what and how’ of solid feeding can be effective in changing maternal feeding practices and, at least in the short term, reducing anthropometric indicators of childhood obesity risk. Analyses of outcomes at later ages are required to determine if these promising effects can be sustained.

A parent-led family-focused treatment program for overweight children aged 5 to 9 years : The PEACH RCT

OBJECTIVE: To evaluate a healthy lifestyle intervention to reduce adiposity in children aged 5 to 9 years and assess whether adding parenting skills training would enhance this effect. PARTICIPANTS AND METHODS: We conducted a single-blinded randomized controlled trial of prepubertal moderately obese (International Obesity Task Force cut points) children, aged 5 to 9 years. The 6-month program targeted parents as the agents of change for implementing family lifestyle changes. Only parents attended group sessions. We measured BMI and waist z scores and parenting constructs at baseline, 6, 12, 18, 24 months. RESULTS: Participants (n = 169; 56% girls) were randomized to a parenting skills plus healthy lifestyle group (n = 85) or a healthy lifestyle–only group (n = 84). At final 24-month assessment 52 and 54 children remained in the parenting skills plus healthy lifestyle and the healthy lifestyle–only groups respectively. There were reductions (P < .001) in BMI z score (0.26 [95% confidence interval: 0.22–0.30]) and waist z score (0.33 [95% confidence interval: 0.26–0.40]). There was a 10% reduction in z scores from baseline to 6 months that was maintained to 24 months with no additional intervention. Overall, there was no significant group effect. A similar pattern of initial improvement followed by stability was observed for parenting outcomes and no group effect. CONCLUSIONS: Using approaches that specifically target parent behavior, relative weight loss of ∼10% is achievable in moderately obese prepubertal children and can be maintained for 2 years from baseline. These results justify an investment in treatment as an effective secondary obesity-prevention strategy.

Toddlers’ food preferences : the impact of novel food exposure, maternal preferences and food neophobia

Food preferences have been identified as a key determinant of children’s food acceptance and consumption. The aim of this study was to identify factors that influence children’s liking for fruits, vegetables and non-core foods. Participants were Australian mothers (median age at delivery=31 years, 18-46 years) and their two-year-old children (M=25 months, SD=1 month; 52% female) allocated to the control group (N=230) of the NOURISH RCT. The effects of repeated exposure to new foods, maternal food preferences and child food neophobia on toddlers’ liking of vegetables, fruits and non-core foods and the proportion never tried were examined via hierarchical regression models; adjusting for key maternal (age, BMI, education) and child covariates (birth weight Z-score, gender), duration of breastfeeding and age of introduction to solids. Maternal preferences corresponded with child preferences. Food neophobia among toddlers was associated with liking fewer vegetables and fruits, and trying fewer vegetables. Number of repeated exposures to new food was not significantly associated with food liking at this age. Results highlight the need to: (i) encourage parents to offer a wide range of foods, regardless of their own food preferences, and (ii) provide parents with guidance on managing food neophobia.

An exploratory study of associations between Australian-Indian mothers’ use of controlling feeding practices, concerns and perceptions of children’s weight and children’s picky eating

Aim This cross-sectional study explores associations between migrant Indian mothers’ use of controlling feeding practices (pressure to eat, restriction and monitoring) and their concerns and perceptions regarding their children’s weight and picky eating behaviour. Methods Two hundred and thirty mothers with children aged 1-5 years, residing in Australia for 1-8 years, participated by completing a self-reported questionnaire. Results Perceptions and concerns regarding children’s weight were not associated with any of the controlling feeding practices. A positive association was noted between pressure feeding and perceptions of pickiness after adjusting for covariates: children’s age, gender and weight-for-age Z-score. Girls, older children, and children with higher weight-for-age z scores were pressure fed to a greater extent. Conclusions This study supports the generalisation of findings from Caucasian literature that pressure feeding and perceptions of pickiness are positively related.

Outcomes of an early feeding practices intervention to prevent childhood obesity

Objective Use a randomised controlled trial (RCT) to evaluate outcomes of a universal intervention to promote protective feeding practices, which commenced in infancy and aimed to prevent childhood obesity Subjects and Methods The NOURISH RCT enrolled 698 first-time mothers (mean age 30.1 years, SD=5.3) with healthy term infants (51% female) aged 4.3 (SD=1.0) months at baseline. Mothers were randomly allocated to self-directed access to usual care or to attend two 6-session interactive group education modules that provided anticipatory guidance on early feeding practices. Outcomes were assessed six months after completion of the second information module, 20 months from baseline and when the children were two years old. Maternal feeding practices were self-reported using validated questionnaires and study-developed items. Study-measured child height and weight were used to calculate BMI Z-score. Results Retention at follow-up was 78%. Mothers in the intervention group reported using responsive feeding more frequently on 6/9 subscales and 8/8 items (Ps ≤.03) and overall less ‘controlling feeding practices’ (P<.001). They also more frequently used feeding practices (3/4 items; Ps <.01) likely to enhance food acceptance. No statistically significant differences were noted in anthropometric outcomes (BMI Z-score: P=.11), nor in prevalence of overweight/obesity (control 17.9% vs. intervention 13.8%, P=.23). Conclusions Evaluation of NOURISH at child age two years found that anticipatory guidance on complementary feeding, tailored to developmental stage, increased use by first-time mothers of 'protective' feeding practices that potentially support the development of healthy eating and growth patterns in young children.

Familial typical migraine: Linkage to chromosome 19p13 and evidence for genetic heterogeneity

Migraine is a frequent familial disorder that, in common with most multifactorial disorders, has an unknown etiology. The authors identified several families with multiple individuals affected by typical migraine using a single set of diagnostic criteria and studied these families for cosegregation between the disorder and markers on chromosome 19, the location of a mutation that causes a rare form of familial hemiplegic migraine (FHM). One large tested family showed both cosegregation and significant allele sharing for markers situated within or adjacent to the FHM locus. Multipoint GENEHUNTER results indicated significant excess allele sharing across a 12.6- cM region containing the FHM Ca2+ channel gene, CACNL1A4 (maximum nonparametric linkage Z score = 6.64, p = 0.0026), with a maximum parametric lod score of 1.92 obtained for a (CAG)(n) triplet repeat polymorphism situated in exon 47 of this gene. The CAG expansion did not, however, appear to be the cause of migraine in this pedigree. Other tested families showed neither cosegregation nor excess allele sharing to chromosome 19 markers. HOMOG analysis indicated heterogeneity, generating a maximum HLOD score of 3.6. It was concluded that Chr19 mutations either in the CACNL1A4 gene or a closely linked gene are implicated in some pedigrees with familial typical migraine, and that the disorder is genetically heterogeneous.

Early life predictors of preschool overweight and obesity : a case–control study in Sri Lanka

Background Childhood obesity increases the risk of obesity in adulthood and is associated with cardiovascular disease risk factors. Our aim was to assess the early life risk factors associated with overweight and obesity among preschool children. Methods In this case–control study, from the 1087 preschool children measured, age, sex and ethnicity matched 71 cases and 71 controls were recruited. Cases and controls were defined according to the WHO 2006 growth standards. The birth and growth characteristics were extracted from the child health development records. Infant feeding practices and maternal factors were obtained from the mother. Rapid weight gain was defined as an increase in weight-for-age Z score (WHO standards) above 0.67 SD from birth to 2 years. The magnitude and significant difference in mean values of the variables associated with overweight and obesity were evaluated using logistic regressions and paired t-test, respectively. Results Cases had significantly shorter duration (months) of breastfeeding (19.4, 24.6, p = 0.003), and smaller duration (months) of exclusive breastfeeding (3.7, 5.1, p = 0.001) compared to controls. Rapid weight gain (OR = 6.3, 95% CI = 2.04–19.49), first born status (OR = 3.6, 95% CI = 1.17-10.91) and pre-pregnancy obesity (OR = 4.0, 95% CI = 1.46-10.76) were positively associated with overweight and obesity. Breastfeeding more than 2 years (OR = 0.2, 95% CI = 0.06-0.57) was negatively associated with overweight and obesity. Conclusion Rapid weight gain within first two years, first–born status and pre-pregnancy obesity of the mother contributed for preschool obesity. Our results suggest that intervention may be indicated earlier in infancy and during the toddler and preschool years to tackle the increasing prevalence of obesity.