Ethnic differences in infant care practices and in the incidence of sudden infant death syndrome in Birmingham

Airway covering during bed-sharing

BACKGROUND

Parent-infant bed-sharing is a common practice in Western post-industrial nations with up to 50% of infants sleeping with their parents at some point during early infancy. However, researchers have claimed that infants may be at risk of suffocation or sudden infant death syndrome related to airway covering or compression in the bed-sharing environment. To further understand the role of airway covering and compression in creating risks for bed-sharing infants, we report here on a sleep-lab trial of two infant sleep conditions.

METHODS

In a sleep-lab environment 20 infants aged 2-3 months old slept in their parents' bed, and in a cot by the bed, on adjacent nights. Infants' oxygen saturation and heart rate were monitored physiologically while infant and parental behaviours were recorded via ceiling-mounted infra-red cameras. Infants served as their own controls. Continuous 8-h recordings were obtained for covering of infant external airways, levels of infant oxygen saturation, infant heart rate, evidence of parental compression/overlying of infant, circumstances leading up to potential infant airway obstruction, and parental awareness of and responses to infant airway covering.

RESULTS

The majority of infants (14/20) spent some part of the bed night with their airways (both mouth and nose) covered, compared with 2/20 on the cot night; however, no consistent effect on either oxygen saturation levels or heart rate was revealed, even during prolonged bouts of airway covering. All cases of airway covering were initiated by parents; 70% were terminated by parents, the remainder by infants. Seven bouts of potential compression were observed with parental limbs resting across infant bodies for lengthy periods, however, in only two cases was the full weight of a parental limb resting on an infant, both events lasting less than 15 s, both being terminated by infant movement.

CONCLUSION

Although numerous authors have suggested that bed-sharing infants face risks because of airway covering by bed-clothes or parental bodies, the present trial does not lend support to this hypothesis.

Sleep practices and environment and the risk of sudden infant death syndrome in Turkey

PURPOSE

The aim of this study is to determine what mothers know about infant sleep practices and the environment.

DESIGN AND METHODS

Data were collected with a semistructured questionnaire. The research was conducted with 231 mothers who delivered an infant and who agreed to participate between September and December 2005.

RESULTS

It was determined that 70.6% (n = 163) of mothers would use a pillow with their sleeping infants, and 44.2% (n = 102) would cover their infants' faces. When infants were alone in a room, 96.5% of mothers would leave them in the supine position.

PRACTICE IMPLICATIONS

Public health interventions should alert women to the increased risk of sudden infant death syndrome associated with identifiable risk factors, and specific intervention campaigns for safe sleeping can be developed for Turkish families.

Natural Parenting — Back to Basics in Infant Care

This review examines an age-old approach to parenting recently rediscovered in Western industrialized societies and known by names such as natural parenting, attachment parenting, and instinctive parenting. Its leading principle is utmost sensitivity to the child's innate emotional and physical needs, resulting in extended breastfeeding on demand, extensive infant carrying on the caregiver's body, and cosleeping of infant and parents. The described practices prevailed during the evolutionary history of the human species and reflect the natural, innate rearing style of the human species to which the human infant has biologically adapted over the course of evolution. An overview of research from diverse areas regarding psychological as well as physiological aspects of early care provides evidence for the beneficial effects of natural parenting. Cross-cultural and historical data is cited to reveal the widespread use of the investigated parenting style. It is concluded that the described approach to parenting provides the human infant with an ideal environment for optimal growth both psychologically and physiologically. It is yet to be determined how much departure from this prototype of optimal human parenting is possible without compromising infant and parental wellbeing. The review also invites a critical reevaluation of current Western childrearing practices.

Ethnicity and obstructive sleep apnoea

There is a scarcity of adult prevalence studies of OSA outside the Caucasian populations of North America, Europe and Australia, and comparisons have been complicated by methodological differences in sleep study settings, respiratory events definition, measured risk factors and clinical outcomes, and the lack of objective parameters for the measurement of ethnicity itself. Comparing studies with the same methodological design and respiratory events definition, recent large-scale prevalence studies from Hong Kong, Korea and India show similar OSA rates to populations of mainly Caucasian composition. OSA is a very complex disorder determined by several phenotypes such as obesity, craniofacial structure and abnormalities in neuromuscular and ventilatory control. Genetics may partially explain some of the ethnic clustering of these phenotypes, modulated by cultural and environmental factors. The exact contribution of these component phenotypes to overall OSA risk will be determined by their varying prevalence and relative risk conferred across ethnic groups. For lesser degrees of obesity, Asians are at risk for a more severe degree of illness compared with Caucasians. Inter-ethnic studies suggests that African-American ethnicity may also be a significant risk factor for OSA. The increased prevalences of OSA among American Indians and Hispanic adults, and increased severity among Pacific Islanders and Maoris, were mainly explained by increased obesity parameters. Most cephalometric studies have largely been conducted without specific regard to ethnicity and comparisons of findings across studies have been mainly limited by differences in sampling methods and the varying selection and definition of measured cephalometric variables. The limited number of studies with inter-ethnic comparative data suggest cephalometric variables and their degree of contribution to OSA vary across ethnic groups.

Ethnicity, infection and sudden infant death syndrome

Epidemiological studies found the incidence of SIDS among Indigenous groups such as Aboriginal Australians, New Zealand Maoris and Native Americans were significantly higher than those for non-Indigenous groups within the same countries. Among other groups such as Asian families in Britain, the incidence of SIDS has been lower than among groups of European origin. Cultural and childrearing practices as well as socio-economic factors have been proposed to explain the greater risk of SIDS among Indigenous peoples; however, there are no definitive data to account for the differences observed. We addressed the differences among ethnic groups in relation to susceptibility to infection because there is evidence from studies of populations of European origin that infectious agents, particularly toxigenic bacteria might trigger the events leading to SIDS. The risk factors for SIDS parallel those for susceptibility to infections in infants, particularly respiratory tract infections which are also major health problems among Indigenous groups. Many of the risk factors identified in epidemiological studies of SIDS could affect three stages in the infectious process: (1) frequency or density of colonisation by the toxigenic species implicated in SIDS; (2) induction of temperature-sensitive toxins; (3) modulation of the inflammatory responses to infection or toxins. In this review we compare genetic, developmental and environmental risk factors for SIDS in ethnic groups with different incidences of SIDS: low (Asians in Britain); moderate (European/Caucasian); high (Aboriginal Australian). Our findings indicate: (1) the major difference was high levels of exposure to cigarette smoke among infants in the high risk groups; (2) cigarette smoke significantly reduced the anti-inflammatory cytokine interleukin-10 responses which control pro-inflammatory responses implicated in SIDS; (3) the most significant effect of cigarette smoke on reduction of IL-10 responses was observed for donors with a single nucleotide polymorphism for the IL-10 gene that is predominant among both Asian and Aboriginal populations. If genetic makeup were a major factor for susceptibility to SIDS, the incidence of these deaths should be similar for both populations. They are, however, significantly different and most likely reflect differences in maternal smoking which could affect frequency and density of colonisation of infants by potentially pathogenic bacteria and induction and control of inflammatory responses.

International Child Care Practices Study: infant sleeping environment

BACKGROUND

The International Child Care Practices Study (ICCPS) has collected descriptive data from 21 centres in 17 countries. In this report, data are presented on the infant sleeping environment with the main focus being sudden infant death syndrome (SIDS) risk factors (bedsharing and infant using a pillow) and protective factors (infant sharing a room with adult) that are not yet well established in the literature.

METHODS

Using a standardised protocol, parents of infants were surveyed at birth by interview and at 3 months of age mainly by postal questionnaire. Centres were grouped according to geographic location. Also indicated was the level of SIDS awareness in the community, i.e. whether any campaigns or messages to "reduce the risks of SIDS" were available at the time of the survey.

RESULTS

Birth interview data were available for 5488 individual families and 4656 (85%) returned questionnaires at 3 months. Rates of bedsharing varied considerably (2-88%) and it appeared to be more common in the samples with a lower awareness of SIDS, but not necessarily a high SIDS rate. Countries with higher rates of bedsharing appeared to have a greater proportion of infants bedsharing for a longer duration (>5 h). Rates of room sharing varied (58-100%) with some of the lowest rates noted in centres with a higher awareness of SIDS. Rates of pillow use ranged from 4% to 95%.

CONCLUSIONS

It is likely that methods of bedsharing differ cross-culturally, and although further details were sought on different bedsharing practices, it was not possible to build up a composite picture of "typical" bedsharing practices in these different communities. These data highlight interesting patterns in child care in these diverse populations. Although these results should not be used to imply that any particular child care practice either increases or decreases the risk of SIDS, these findings should help to inject caution into the process of developing SIDS prevention campaigns for non-Western cultures.

NMR study of virenose and dihydrohydroxystreptose isolated from Coxiella burnetii phase I lipopolysaccharide

A lipopolysaccharide (LPS) isolated from Coxiella burnettii in virulent phase I contains in its O-polysaccharide chain two unusual sugars, virenose (6-deoxy-3-C-methylgulose) and dihydrohydroxystreptose [3-C-(hydroxymethyl)lyxose]. The sugars were isolated from LPS I, after acid hydrolysis and removal of lipid A, by a combination of HPLC and preparative paper chromatography. Their enantiomeric forms and ring conformations were established from optical rotation and NMR data. Two-dimensional COSY, HSQC, and HMBC as well as one- and two-dimensional NOEs were used to assign all proton and carbon signals in both monosaccharides. Virenose was found to be the D-gulo enantiomer with the 4C1 ring conformation and dihydrohydroxystreptose was shown to be the L-lyxo enantiomer also with the 4C1 conformation. The latter sugar was reported [S. Schramek, J. Radziejewska-Lebrecht, and H. Mayer, Eur. J. Biochem., 148 (1985) 455-461] to be present in LPS I in a furanose form, and it appears that a furanose to pyranose tautomerization took place in the course of the isolation procedure.