Anticipatory guidance to prevent infant sleep problems within a randomised controlled trial: infant, maternal and partner outcomes at 6 months of age

OBJECTIVE

To evaluate the effectiveness of sleep education delivered antenatally and at 3 weeks postpartum to prevent infant sleep problems at 6 months of age.

DESIGN

Sleep intervention within a randomised controlled trial for the Prevention of Overweight in Infancy (POI) study.

PARTICIPANTS

802 families were randomly allocated to one of four groups: usual care (control), sleep intervention (sleep), food, activity and breastfeeding intervention (FAB), and combined group receiving both interventions (combination).

INTERVENTIONS

All groups received standard Well Child care. The sleep intervention groups (sleep and combination) received an antenatal group education session (all mothers and most partners) emphasising infant self-settling and safe sleeping, and a home visit at 3 weeks reinforcing the antenatal sleep education. FAB and combination groups received four contacts providing education and support on breast feeding, food and activity up to 4 months postpartum.

OUTCOME MEASURES

Here we report secondary sleep outcomes from the POI study: the prevalence of parent-reported infant sleep problems and night waking, and differences in sleep duration. Additional outcomes reported include differences in infant self-settling, safe sleep practices, and maternal and partner reports of their own sleep, fatigue and depression symptoms.

RESULTS

Linear or mixed linear regression models found no significant intervention effects on sleep outcomes, with 19.1% of mothers and 16.6% of partners reporting their infant's sleep a problem at 6 months. Actigraphy estimated the number of night wakings to be significantly reduced (8%) and the duration of daytime sleep increased (6 min) in those groups receiving the sleep intervention compared with those who did not. However, these small differences were not clinically significant and not observed in 24 hours infant sleep diary data. No other differences were observed.

CONCLUSION

A strategy delivering infant sleep education antenatally and at 3 weeks postpartum was not effective in preventing the development of parent-reported infant sleep problems.

Lactation Consultant Support from Late Pregnancy with an Educational Intervention at 4 Months of Age Delays the Introduction of Complementary Foods in a Randomized Controlled Trial

BACKGROUND

Although the WHO recommends that complementary feeding in infants should begin at 6 mo of age, it often begins before this in developed countries.

OBJECTIVE

Our objective was to determine whether lactation consultant (LC) support, with educational resources given at 4-mo postpartum, can delay the introduction of complementary foods until around 6 mo of age.

METHODS

A total of 802 mother-infant pairs were recruited from the single maternity hospital serving Dunedin, New Zealand (59% response rate) and randomly assigned to the following: 1) usual care (control group); 2) infant sleep education intervention (Sleep); 3) food, activity, and breastfeeding intervention (FAB); or 4) combination (both) intervention (Combo). Certified LCs delivered 3 intervention sessions (late pregnancy and 1-wk and 4-mo postpartum). The 4-mo contact used educational resources focused on developmental readiness for complementary foods. Age when complementary foods were introduced was obtained from repeated interviews (monthly from 3- to 27-wk postpartum).

RESULTS

A total of 49.5% and 87.2% of infants received complementary foods before 5 and 6 mo of age, respectively. There was evidence of group differences in the number of infants introduced to complementary foods before 5 mo (P = 0.006), with those receiving support and resources (FAB and Combo groups combined; 55.6%) more likely to wait until at least 5 mo compared with controls (control and Sleep groups combined; 43.3%) (OR: 1.52; 95% CI: 1.08, 2.16). However, there was no evidence they were more likely to wait until 6 mo of age (P = 0.52). Higher maternal age, higher parity, and a less positive attitude toward breastfeeding were positively associated, and drinking alcohol during pregnancy was negatively associated, with later age of introduction of complementary foods.

CONCLUSIONS

Providing an LC and educational resources at 4-mo postpartum to predominantly well-educated, mainly European, women can delay the introduction of complementary foods until 5 mo of age, but not until the WHO recommendation of 6 mo. This trial was registered at clinicaltrials.gov as NCT00892983.

Limited visual control of the intelligibility of speech in face-to-face dialogue

Speakers are thought to articulate individual words in running speech less carefully whenever additional nonacoustic information can help listeners recognize what is said (Fowler & Housum, 1987; Lieberman, 1963). Comparing single words excerpted from spontaneous dialogues and control tokens of the same words read by the same speakers in lists, Experiment 1 yielded a significant but general effect of visual context: Tokens introducing 71 new entities in dialogues in which participants could see one another's faces were more degraded (less intelligible to 54 naive listeners) than were tokens of the same words from dialogues with sight lines blocked. Loss of clarity was not keyed to moment-to-moment visual behavior. Subjects with clear sight lines looked at each other too rarely to account for the observed effect. Experiment 2 revealed that tokens of 60 words uttered while subjects were looking at each other were significantly less degraded (in length and in intelligibility to 72 subjects) vis-à-vis controls than were spontaneous tokens of the same words produced when subjects were looking elsewhere. Intelligibility loss was mitigated only when listeners looked at speakers. Two separate visual effects are discussed, one of the global availability and the other of the local use of the interlocutor's face.

Putative active site template model for cytochrome P4502C9 (tolbutamide hydroxylase)

Binding of substrates to the active site of cytochrome P450 enzymes largely relies on hydrophobic interactions. However, other binding interactions can take place giving the enzyme high regioselectivity and even stereoselectivity. For instance, within the major human cytochrome P450s involved in drug metabolism, cytochrome P4502D6 (CYP2D6) relies on an ion-pair interaction as a major binding factor. There are now a number of substrates reported that have routes of metabolism ascribed specifically to cytochrome P4502C9 (CYP2C9), the isoform mainly responsible for tolbutamide hydroxylation. Although chemically diverse, these substrates have the capability to be hydrogen bond donors (or acceptors). The substrate specificity has been rationalized in terms of a hydrogen bond donor/acceptor model and, by use of molecular modeling, an active site template model for CYP2C9 has been generated. The substrates modeled were phenytoin, warfarin, ibuprofen, naproxen, diclofenac, delta 1-tetrahydrocannabinol, 58C80, and tolbutamide. In addition to the substrates, the potent, selective inhibitor sulfaphenazole was also included in the modeling. An initial hydrogen bond donor site (N2) was identified on phenytoin, the most rigid of the substrates. Corresponding hydrogen bond donation sites were then identified on all of the molecules studied. Using molecular modeling, the site of metabolism and the hydrogen bond donation sites of the molecules were then overlaid on phenytoin to produce the putative active site model. The resultant model is described by a, the distance between the site of metabolism (Y), and the hydrogen bond donor heteroatom (X) and C, the angle between this and the hydrogen bond. The mean dimensions (+/- SD) for the nine substrates and one inhibitor (a = 6.7 +/- 1.0 A, C = 133 +/- 21 degrees) illustrate the degree of overlap achieved.