Restricting diet for perceived health benefit: A mixed-methods exploration of peripartum food taboos in rural Cambodia.

Food taboos encompass food restrictions practiced by a group that go beyond individual preferences. During pregnancy and lactation, food taboos may contribute to inadequate nutrition and poor maternal and infant health. Restriction of specific fish, meat, fruits and vegetables is common among peripartum women in many Southeast Asian countries, but data from Cambodia are lacking. In this mixed-methods study, 335 Cambodian mothers were asked open-ended questions regarding dietary behaviours during pregnancy and up to 24 weeks postpartum. Descriptive statistics and content analysis were used to characterize food taboos and multiple logistic regression analyses were conducted to identify predictors of this practice. Participants were 18-44 years of age, all of Khmer ethnicity and 31% were primiparous. Sixty-six per cent of women followed food taboos during the first 2 weeks postpartum, whereas ~20% of women restricted foods during other peripartum periods. Pregnancy taboos were often beneficial, including avoidance of sugar-sweetened beverages, coffee and alcohol. Conversely, postpartum avoidances typically included nutrient-dense foods such as fish, raw vegetables and chicken. Food taboos were generally followed to support maternal and child health. No significant predictors of food taboos during pregnancy were identified. Postpartum, each additional live birth a woman had reduced her odds of following food taboos by 24% (odds ratio [95% confidence interval]: 0.76 [0.61-0.95]). Specific food taboo practices and rationales varied greatly between women, suggesting that food taboos are shaped less by a strict belief system within the Khmer culture and more by individual or household understandings of food and health during pregnancy and postpartum.

Thiamine supplementation holds neurocognitive benefits for breastfed infants during the first year of life.

Women reliant on mostly rice-based diets can have inadequate thiamine intake, placing breastfed infants at risk of thiamine deficiency and, in turn, physical and cognitive impairments. We investigated the impact of maternal thiamine supplementation doses on infants' cognitive, motor, and language development across the first year. In this double-blind, four-parallel-arm, randomized controlled trial, healthy mothers of exclusively breastfed newborn infants were recruited in Kampong Thom, Cambodia. At 2 weeks postnatal, women (n = 335) were randomized to one of four treatment groups to consume one capsule/day with varying amounts of thiamine for 22 weeks: 0, 1.2, 2.4, and 10 mg. At 2, 12, 24, and 52 weeks of age, infants were assessed with the Mullen Scales of Early Learning (MSEL) and the Caregiver Reported Early Development Instrument (CREDI). Multiple regression and mixed effects modeling suggest that by 6 months of age, the highest maternal thiamine dose (10 mg/day) held significant benefits for infants' language development, but generally not for motor or visual reception development. Despite having achieved standardized scores on the MSEL that approximated U.S. norms by 6 months, infants showed a significant drop relative to these norms in both language domains following trial completion, indicating that nutritional interventions beyond 6 months may be necessary.

Low-dose thiamine supplementation of lactating Cambodian mothers improves human milk thiamine concentrations: a randomized controlled trial.

BACKGROUND: Infantile beriberi-related mortality is still common in South and Southeast Asia. Interventions to increase maternal thiamine intakes, and thus human milk thiamine, are warranted; however, the required dose remains unknown. OBJECTIVES: We sought to estimate the dose at which additional maternal intake of oral thiamine no longer meaningfully increased milk thiamine concentrations in infants at 24 wk postpartum, and to investigate the impact of 4 thiamine supplementation doses on milk and blood thiamine status biomarkers. METHODS: In this double-blind, 4-parallel arm randomized controlled dose-response trial, healthy mothers were recruited in Kampong Thom, Cambodia. At 2 wk postpartum, women were randomly assigned to consume 1 capsule, containing 0, 1.2 (estimated average requirement), 2.4, or 10 mg of thiamine daily from 2 through 24 weeks postpartum. Human milk total thiamine concentrations were measured using HPLC. An Emax curve was plotted, which was estimated using a nonlinear least squares model in an intention-to-treat analysis. Linear mixed-effects models were used to test for differences between treatment groups. Maternal and infant blood thiamine biomarkers were also assessed. RESULTS: In total, each of 335 women was randomly assigned to1 of the following thiamine-dose groups: placebo (n = 83), 1.2 mg (n = 86), 2.4 mg (n = 81), and 10 mg (n = 85). The estimated dose required to reach 90% of the maximum average total thiamine concentration in human milk (191 µg/L) is 2.35 (95% CI: 0.58, 7.01) mg/d. The mean ± SD milk thiamine concentrations were significantly higher in all intervention groups (183 ± 91, 190 ± 105, and 206 ± 89 µg/L for 1.2, 2.4, and 10 mg, respectively) compared with the placebo group (153 ± 85 µg/L; P < 0.0001) and did not significantly differ from each other. CONCLUSIONS: A supplemental thiamine dose of 2.35 mg/d was required to achieve a milk total thiamine concentration of 191 µg/L. However, 1.2 mg/d for 22 wk was sufficient to increase milk thiamine concentrations to similar levels achieved by higher supplementation doses (2.4 and 10 mg/d), and comparable to those of healthy mothers in regions without beriberi. This trial was registered at clinicaltrials.gov as NCT03616288.

Assessment of salt intake to consider salt as a fortification vehicle for thiamine in Cambodia.

Thiamine deficiency is a public health issue in Cambodia. Thiamine fortification of salt has been proposed; however, the salt intake of lactating women, the target population, is currently unknown. We estimated salt intakes among lactating women (<6 months postpartum) using three methods: repeat observed-weighed intake records and 24-h urinary sodium excretions (n = 104), and household salt disappearance (n = 331). Usual salt intake was estimated by adjusting for intraindividual intakes using the National Cancer Institute method, and a thiamine salt fortification scenario was modeled using a modified estimated average requirement (EAR) cut-point method. Unadjusted salt intake from observed intakes was 9.3 (8.3-10.3) g/day, which was not different from estimated salt intake from urinary sodium excretions, 9.0 (8.4-9.7) g/day (P = 0.3). Estimated salt use from household salt disappearance was 11.3 (10.7-11.9) g/person/day. Usual (adjusted) salt intake from all sources was 7.7 (7.4-8.0) g/day. Assuming no stability losses, a modeled fortification dose of 275 mg thiamine/kg salt could increase thiamine intakes from fortified salt to 2.1 (2.0-2.2) mg/day, with even low salt consumers reaching the EAR of 1.2 mg/day from fortified salt alone. These findings, in conjunction with future sensory and stability research, can inform a potential salt fortification program in Cambodia.

Thiamine dose response in human milk with supplementation among lactating women in Cambodia: study protocol for a double-blind, four-parallel arm randomised controlled trial.

INTRODUCTION: Thiamine (vitamin B1) deficiency remains a concern in Cambodia where women with low thiamine intake produce thiamine-poor milk, putting their breastfed infants at risk of impaired cognitive development and potentially fatal infantile beriberi. Thiamine fortification of salt is a potentially low-cost, passive means of combating thiamine deficiency; however, both the dose of thiamine required to optimise milk thiamine concentrations as well as usual salt intake of lactating women are unknown. METHODS AND ANALYSIS: In this community-based randomised controlled trial, 320 lactating women from Kampong Thom, Cambodia will be randomised to one of four groups to consume one capsule daily containing 0, 1.2, 2.4 or 10 mg thiamine as thiamine hydrochloride, between 2 and 24 weeks postnatal. The primary objective is to estimate the dose where additional maternal intake of thiamine no longer meaningfully increases infant thiamine diphosphate concentrations 24 weeks postnatally. At 2, 12 and 24 weeks, we will collect sociodemographic, nutrition and health information, a battery of cognitive assessments, maternal (2 and 24 weeks) and infant (24 weeks only) venous blood samples (biomarkers: ThDP and transketolase activity) and human milk samples (also at 4 weeks; biomarker: milk thiamine concentrations). All participants and their families will consume study-provided salt ad libitum throughout the trial, and we will measure salt disappearance each fortnight. Repeat weighed salt intakes and urinary sodium concentrations will be measured among a subset of 100 participants. Parameters of Emax dose-response curves will be estimated using non-linear least squares models with both 'intention to treat' and a secondary 'per-protocol' (capsule compliance ≥80%) analyses. ETHICS AND DISSEMINATION: Ethical approval was obtained in Cambodia (National Ethics Committee for Health Research 112/250NECHR), Canada (Mount Saint Vincent University Research Ethics Board 2017-141) and the USA (University of Oregon Institutional Review Board 07052018.008). Results will be shared with participants' communities, as well as relevant government and scientific stakeholders via presentations, academic manuscripts and consultations. TRIAL REGISTRATION NUMBER: NCT03616288.

Contributions of early adversity to pro-inflammatory phenotype in infancy: the buffer provided by attachment security.

Adversity early in life is associated with systemic inflammation by adolescence and beyond. At present, few studies have investigated the associations between different forms of adversity and inflammation during infancy, making it difficult to specify the origins of disease vulnerability. This study examined the association between multiple forms of early adversity - socioeconomic status disadvantage, familial stress, maternal depression, and security of attachment - and individual differences in a composite measure of pro-inflammatory cytokines (IL-1ß, IL-6, IL-8, and tumor necrosis factor-alpha) and the inflammatory protein C-reactive protein that were collected via saliva when (n = 49) children were 17 months old. In addition to gauging the direct effects of adversity, we also tested the hypothesis that infants' attachment relationship with their mother might buffer infants against the immunologic effects of early adversity. Results show that familial stress, maternal depression, and security of attachment were directly associated with infant salivary inflammation and that attachment status moderated the effect of maternal depression. The findings suggest that exposure to certain forms of adversity very early in life may engender a pro-inflammatory phenotype with possible life-long implications for health.

Increased levels of inflammation among infants with disorganized histories of attachment.

Early life adversity is associated with adult elevations of inflammatory markers such as circulating levels of C-reactive protein (CRP). Few studies have examined inflammation levels during infancy nor the associations between sources of adversity and concurrent inflammation early in life. Existing evidence suggests that early adversity in the form of compromised caregiving relationships can embed itself into young children's biology with implications for lifelong development. This study examined the association between infants' histories of attachment with their mothers and salivary concentrations of CRP, all of which were assessed when infants were 17 months of age. Results show that infants with disorganized attachments histories and those exhibiting disorganized and avoidant regulatory behaviors when faced with an attachment stressor were all associated with significantly elevated levels of salivary CRP. These results suggest that exposure to significant interpersonal adversity very early in life may engender a proinflamotry phenotype with life-long implications for health.

Shaping emotion regulation: attunement, symptomatology, and stress recovery within mother-infant dyads.

The foundations of emotion regulation are organized, in part, through repeated interactions with one's caregiver in infancy. Less is known about how stress physiology covaries between a mother and her infant within these interactions, leaving a gap in our understanding of how the biological basis of emotion regulation develops. This study investigated physiological attunement between mothers and their 5-month-old infants, as well as the influence of maternal depression and anxiety, during stress recovery. During the reengagement phase of the Still Face Paradigm, mother-infant dyads exhibited negative attunement, as measured by inverse covariation of respiratory sinus arrhythmia (RSA). Increases in maternal RSA corresponded to decreases in infant RSA, underscoring dyadic adjustment during recovery. Moreover, infant regulation differed as a function of maternal anxiety, with more anxious mothers having infants with higher RSA during reengagement. Implications for the consolidation of regulatory capabilities within the context of the early caregiving relationship are discussed.

Rates of motorcycle helmet use and reasons for non-use among adults and children in Luang Prabang, Lao People's Democratic Republic.

BACKGROUND: Motorcycles make up 81 % of the total vehicle population and 74 % of road traffic deaths in Lao PDR. Helmets reduce the risk and severity of injuries resulting from motorcycle accidents by 72 %. Although Lao law mandates motorcycle helmet use among drivers and passengers, the prevalence of helmet use in Luang Prabang, Lao PDR is unknown. This project aimed to measure the prevalence of motorcycle helmet use among riders (i.e., drivers and passengers) in Luang Prabang. METHODS: An observational survey in Luang Prabang was conducted in February 2015 to measure the prevalence of motorcycle helmet use among drivers and passengers. Additionally, non-helmet wearing riders were surveyed to identify the reasons for helmet non-use. RESULTS: Of 1632 motorcycle riders observed, only 16.2 % wore helmets. Approximately 29 % of adults wore helmets while less than 1 % of all children wore helmets. When surveyed about attitudes towards helmet use, the majority of adult drivers indicated that they did not like how adult helmets feel or made them look. Additionally, almost half of motorcyclists who did not own child helmets reported that their child was too young to wear a helmet. CONCLUSIONS: Our finding that children wear helmets at significantly lower rates compared to adults is consistent with findings from neighboring countries in Southeast Asia. Results of this study have implications for public health campaigns targeting helmet use, especially among children.

Why Mothers and Young Children Agree or Disagree in Their Reports of the Child's Problem Behavior.

This study examined multiple determinants of discrepancies between mother and child reports of problem behavior. In 5,414 6-year-olds, child problem behavior was assessed by self-report using the Berkeley Puppet Interview and by maternal report using the Child Behavior Checklist. Patterns in mother-child reports were modeled using latent profile analysis. Four profiles, differing in problem level, and the direction and magnitude of mother-child discrepancies, were identified: one profile representing agreement (46%), another representing slight discrepancies (30%), and two representing higher problem levels and more discrepancies. In the latter two profiles either children (11%) or mothers (13%) reported more problems. Compared to the first profile, the second was predominantly characterized by a positive family environment, the third by child cognitive difficulties, and the fourth by harsh discipline and poor family functioning. Knowledge about specific child/family characteristics that contribute to mother-child discrepancies can help to interpret informants' reports and to make diagnostic decisions.

Little tyrants or just plain tired: evaluating attributions for caregiving outcomes across the transition to parenthood.

There is now substantial evidence that parental attributions for power over negative caregiving outcomes play an important role in the intergenerational transmission of child maltreatment. Despite the substantial research and clinical significance of this construct, and the widely held assumption that it represents a trait-like attributional style, there is a lack of empirical support for its long-term stability, especially over the transition to parenthood. The present study examined the stability of 88 at-risk women's perceived power over caregiving failure from the 3rd trimester of their 1st pregnancy to 18 months postnatal. Although results showed no significant change in overall self-reported perceived power over caregiving failure across time, subcomponents that separately assess perceived importance of adult and child factors both decreased over time, driven by increasing external attributions. Examination of subscale scores further revealed consistency in women's attributional style for their own and their child's behavior, and for positive and negative events, over time. Individual differences in these patterns suggested that past and present difficulties interfered with normative shifts such that maternal stress and history of trauma were associated with an increased sense that children control problematic events while decreasing mothers' own sense of control. Research and clinical implications are discussed.

Young children's self-reported emotional, behavioral, and peer problems: the Berkeley Puppet Interview.

Adult observers are typically the only informants on emotional and behavioral problems in young children. Although additional information can be provided by child self-report, few validated, structured instruments are available to obtain self-report from young children. The Berkeley Puppet Interview (BPI) has been developed to obtain structured self-reports on multiple domains of mental health and social well-being. This study was the 1st to evaluate the psychometric properties of the BPI in a large sample. We studied 8 a priori scales of the interview in a Dutch community sample of 6,375 children ages 5-7 years. Using confirmatory factor analysis, we demonstrated adequate fit (Tucker-Lewis index = .90; comparative fit index = .90; root-mean-square error of approximation = .03) of a multidimensional model with 50 items loading on 8 latent factors (Depression, Separation Anxiety, Overanxious, Oppositional Defiant, Overt Hostility, Conduct Problems, Bullied by Peers, and Peer Acceptance/Rejection). This model was invariant across gender. Children reported anxiety-related problems more frequently than depressive problems, behavioral problems, or difficulties in peer relations. Reliability analyses showed that 3 broadband scales designated as Internalizing, Externalizing, and Peer Relations were homogeneous constructs (αs = .68-.79). Higher scores on most BPI scales were associated with lower maternal education, lower family income, and non-Western ethnicity. Boys reported more behavioral and peer relation problems, whereas girls reported more emotional problems. The findings indicate that young children from socioeconomically and demographically diverse backgrounds are capable of providing valid, multidimensional information on their emotional, behavioral, and peer relation problems using the BPI. Young children's self-report is a promising addition to existing assessment tools.

Mothers' vagal regulation during the Still-Face Paradigm: normative reactivity and impact of depression symptoms.

This study examined mothers' physiological reactivity in response to infant distress during the Still-Face Paradigm. We aimed to explore normative regulatory profiles and associated physiological and behavioral processes in order to further our understanding of what constitutes regulation in this dyadic context. We examined physiological patterns--vagal tone, indexed by respiratory sinus arrhythmia (RSA)--while mothers maintained a neutral expression over the course of the still face episode, as well as differential reactivity patterns in mothers with depression symptoms compared to non-depressed mothers. Behavioral and physiological data were collected from mothers of 5-month-old infants during the emotion suppression phase of the Still-Face Paradigm. We used Hierarchical Linear Modeling to examine changes in mothers' RSA during infant distress and explored maternal depression as a predictor of physiological profiles. Mothers were generally able to maintain a neutral expression and simultaneously demonstrated a mean-level increase in RSA during the still face episode compared to baseline, indicating an active regulatory response overall. A more detailed time-course examination of RSA trajectories revealed that an initial RSA increase was typically followed by a decrease in response to peak infant distress, suggesting a physiological mobilization response. However, this was not true of mothers with elevated depressive symptoms, who showed no change in RSA during infant distress. These distinct patterns of infant distress-related physiological activation may help to explain differences in maternal sensitivity and adaptive parenting.

Respiratory control when measuring respiratory sinus arrhythmia during a talking task.

The current study explored the effects of talking on respiratory sinus arrhythmia (RSA) during a semi-structured emotional interview (Adult Attachment Interview) using 76 female undergraduates. The effectiveness of 2 different methodological approaches (i.e. talking baseline or transfer function) was explored as respiratory control during talking tasks. RSA was collected during resting baseline, talking baseline, and interview conditions. Subjective reports of distress were higher in the interview than in the other 2 conditions. Mean RSA levels were significantly lower in the 2 talking tasks than in the resting baseline. After applying a transfer function for respiratory control, there were no significant differences between the 3 conditions. Moderator analyses yielded lower RSA values in the talking baseline and interview conditions for participants who reported greater distress during the interview. It was concluded that respiratory controls are likely necessary when using RSA in talking paradigms and that both approaches appeared to be adequate.

Predicting maternal sensitivity: The roles of postnatal depressive symptoms and parasympathetic dysregulation.

Previous research has established that maternal depression is a risk factor for a variety of negative developmental outcomes among infants and children. Although low levels of maternal sensitivity have been hypothesized to explain this risk, the biological mechanisms underlying the association between maternal depressive symptoms and low levels of maternal sensitivity have been largely underexplored. This study examined the roles of postnatal depressive symptoms and parasympathetic nervous system functioning as predictors of low levels of maternal sensitivity, during a stressful mother-infant interaction-the reunion phase of the Still-Face Paradigm. Depressive symptoms and traitlike predispositions toward parasympathetic dysregulation, as indexed by low resting levels of respiratory sinus arrhythmia, were associated independently with less sensitive parenting. Discussion considers that during stressful mother-infant interactions, both mothers with depressive symptoms and mothers predisposed to parasympathetic dysregulation may have fewer emotional, physiological, and psychological resources with which to respond sensitively to their infants' cues.

The impact of parents, child care providers, teachers, and peers on early externalizing trajectories.

This study utilized growth mixture modeling to examine the impact of parents, child care providers, teachers, and peers on the prediction of distinct developmental patterns of classroom externalizing behavior in elementary school. Among 241 children, three groups were identified. 84.6% of children exhibited consistently low externalizing behavior. The externalizing behavior of the Chronic High group (5.8%) remained elevated throughout elementary school; it increased over time in the Low Increasing group (9.5%). Negative relationships with teachers and peers in the kindergarten classroom increased the odds of having chronically high externalizing behavior. Teacher-child conflict increased the likelihood of a developmental pattern of escalating externalizing behavior. Boys were overrepresented in the behaviorally risky groups, and no sex differences in trajectory types were found.

Interparental relationship dynamics and cardiac vagal functioning in infancy.

This study examined associations between interparental relationship dynamics and vagus system functioning in infancy. The functioning of the vagus system, part of the parasympathetic nervous system, indexes emotional reactivity and regulation. Interparental avoidance and dyadic adjustment constitute the focus of this study in order to bring attention to relationship dynamics not subsumed under overt conflict. Infants' baseline vagal tone and change in vagal tone in response to a novel toy were assessed at 5 months in a sample of high-risk mother-infant dyads (n=77). Maternal report of interparental avoidance demonstrated an association with infants' baseline vagal tone, while interparental dyadic adjustment was associated with change in infants' vagal tone from baseline to the novel toy. Infant gender moderated these associations. Maternal sensitivity did not mediate interparental relationship dynamics and infants' vagal functioning. Results are discussed in the context of emotional security theory.

Linking marital conflict and children's adjustment: the role of young children's perceptions.

Young children's (n = 96) perceptions and appraisals of their parents' marital conflict were evaluated at age 5 and again at age 6. Concurrent reports of marital conflict by each parent and teachers' reports of children's classroom adjustment served as criteria against which to evaluate the validity of young children's perceptions. Children's perceptions of their parents' marital relationship were significantly correlated with spouses' reports at ages 5 and 6, as well as correlated with teacher reports of internalizing and externalizing problems. Consistent with the cognitive-contextual theory, children's tendency to blame themselves for their parents' conflict partially mediated the link between marital conflict and children's internalizing symptoms. In contrast, children's reports that they become involved in their parents' conflict partially mediated the effect of marital conflict on externalizing problems.

A prospective test of the negative affect model of substance abuse: moderating effects of social support.

The authors tested whether dimensions of negative affect--specifically, trait levels of negative emotionality and state levels of depressive symptoms--increased risk for substance abuse onset and whether perceived social support moderated this relation using data from a 5-year prospective study of 496 school-recruited adolescent girls. Initial negative emotionality, but not depressive symptoms, and deficits in parental, but not peer, support predicted future substance abuse onset in a multivariate hazard model. Tests of the interaction between negative affect dimensions and social support suggested that support did not moderate the relation of negative affect to risk for substance abuse onset. Results provide prospective support for the etiological role in the onset of substance abuse of trait-linked negative affect and of parental support.

Developmental trajectories of co-occurring depressive, eating, antisocial, and substance abuse problems in female adolescents.

Growth trajectories of co-occurring symptomatology were examined in a community sample of 493 female adolescents who were followed annually from early to late adolescence. On average, depression, eating disorder, and substance abuse symptoms increased over time, whereas antisocial behavior decreased. Increases in each symptom domain were associated with relative increases in all other domains. Initial depressive and antisocial behavior symptoms predicted future increases in the other; substance abuse and antisocial behavior symptoms also showed prospective reciprocal relations. Initial depression predicted increases in eating disorder and substance abuse symptoms. Initial eating disorder symptoms predicted increases in substance abuse problems. Finally, the results suggest that the developmental covariation between depressive and eating disorder symptoms and between antisocial behavior and substance abuse symptoms was accounted for by distinct but related 2nd-order growth parameters.