Environment of infants during sleep and risk of the sudden infant death syndrome: results of 1993-5 case-control study for confidential inquiry into stillbirths and deaths in infancy. Confidential Enquiry into Stillbirths and Deaths Regional Coordinators and Researchers

Bed-sharing in the absence of hazardous circumstances: is there a risk of sudden infant death syndrome? An analysis from two case-control studies conducted in the UK

Objective

The risk of sudden infant death syndrome (SIDS) among infants who co-sleep in the absence of hazardous circumstances is unclear and needs to be quantified.

Design

Combined individual-analysis of two population-based case-control studies of SIDS infants and controls comparable for age and time of last sleep.

Setting

Parents of 400 SIDS infants and 1386 controls provided information from five English health regions between 1993–6 (population: 17.7 million) and one of these regions between 2003–6 (population:4.9 million).

Results

Over a third of SIDS infants (36%) were found co-sleeping with an adult at the time of death compared to 15% of control infants after the reference sleep (multivariate OR = 3.9 [95% CI: 2.7–5.6]). The multivariable risk associated with co-sleeping on a sofa (OR = 18.3 [95% CI: 7.1–47.4]) or next to a parent who drank more than two units of alcohol (OR = 18.3 [95% CI: 7.7–43.5]) was very high and significant for infants of all ages. The risk associated with co-sleeping next to someone who smoked was significant for infants under 3 months old (OR = 8.9 [95% CI: 5.3–15.1]) but not for older infants (OR = 1.4 [95% CI: 0.7–2.8]). The multivariable risk associated with bed-sharing in the absence of these hazards was not significant overall (OR = 1.1 [95% CI: 0.6–2.0]), for infants less than 3 months old (OR = 1.6 [95% CI: 0.96–2.7]), and was in the direction of protection for older infants (OR = 0.1 [95% CI: 0.01–0.5]). Dummy use was associated with a lower risk of SIDS only among co-sleepers and prone sleeping was a higher risk only among infants sleeping alone.

Conclusion

These findings support a public health strategy that underlines specific hazardous co-sleeping environments parents should avoid. Sofa-sharing is not a safe alternative to bed-sharing and bed-sharing should be avoided if parents consume alcohol, smoke or take drugs or if the infant is pre-term.

Using a pacifier to decrease sudden infant death syndrome: an emergency department educational intervention

Background. Pacifier use decreases the risk of sudden infant death syndrome (SIDS). An emergency department (ED) visit may provide an opportunistic ‘teachable moment’ for parents.

Objectives. To test the hypotheses (1) that caregivers were less familiar with the role of pacifiers in sudden infant death (SIDS) prevention than other recommendations, and (2) that an ED educational intervention would increase pacifier use in infants younger than six months, and (3) that otitis media would not occur more frequently in pacifier users.

Methods. We did an intervention-group-only longitudinal study in a county hospital ED. We measured pacifier use infants and baseline knowledge of SIDs prevention recommendations in caregivers. We followed up three months later to determine pacifier use, and 12 months later to determine episodes of otitis media.

Results. We analyzed data for 780 infants. Parents knew of advice against co-sleeping in 469/780 (60%), smoking in 660/776 (85%), and prone sleeping in 613/780 (79%). Only 268/777 (35%) knew the recommendation to offer a pacifier at bedtime. At enrollment 449/780 (58%) did not use a pacifier. Of 210/338 infants aged less than 6 months followed up 41/112 (37%) non-users had started using a pacifier at bedtime (NNT 3). Over the same period, 37/98 (38%) users had discontinued their pacifier. Otitis media did not differ between users and non-users at 12 months.

Conclusion. Caregiver knowledge of the role of pacifiers in SIDS prevention was less than for other recommendations. Our educational intervention appeared to increase pacifier use. Pacifier use was not associated with increased otitis media.

Heat stress and sudden infant death syndrome--stress gene expression after exposure to moderate heat stress

The aim of the present study was to investigate stress gene expression in cultured primary fibroblasts established from Achilles tendons collected during autopsies from sudden infant death syndrome (SIDS) cases, and age-matched controls (infants dying in a traumatic event). Expression of 4 stress responsive genes, HSPA1B, HSPD1, HMOX1, and SOD2, was studied by quantitative reverse transcriptase PCR analysis of RNA purified from cells cultured under standard or various thermal stress conditions. The expression of all 4 genes was highly influenced by thermal stress in both SIDS and control cells. High interpersonal variance found in the SIDS group indicated that they represented a more heterogeneous group than controls. The SIDS group responded to thermal stress with a higher expression of the HSPA1B and HSPD1 genes compared to the control group, whereas no significant difference was observed in the expression of SOD2 and HMOX1 between the two groups. The differences were related to the heat shock treatment as none of the genes were expressed significantly different in SIDS at base levels at 37 °C. SOD2 and HMOX1 were up regulated in both groups, for SOD2 though the expression was lower in SIDS at all time points measured, and may be less related to heat stress. Being found dead in the prone position (a known risk factor for SIDS) was related to a lower HSPA1B up-regulation in SIDS compared to SIDS found on their side or back. The study demonstrates the potential usefulness of gene expression studies using cultured fibroblasts established from deceased individuals as a tool for molecular and pathological investigations in forensic and biomedical sciences.

Serotonin gene variants are unlikely to play a significant role in the pathogenesis of the sudden infant death syndrome

Sudden infant death syndrome (SIDS) is defined as the sudden and unexpected death of an infant less than 12 months of age that is related to a sleep period and remains unexplained after a complete autopsy, death scene investigation, and review of the clinical history. The cause of SIDS is unknown, but a major subset of SIDS is proposed to result from abnormalities in serotonin (5-HT) and related neurotransmitters in regions of the lower brainstem that result in failure of protective homeostatic responses to life-threatening challenges during sleep. Multiple studies have implicated gene variants that affect different elements of 5-HT neurotransmission in the pathogenesis of these abnormalities in SIDS. In this review I discuss the data from these studies together with some new data correlating genotype with brainstem 5-HT neurochemistry in the same SIDS cases and conclude that these gene variants are unlikely to play a major role in the pathogenesis of the medullary 5-HT abnormalities observed in SIDS.

Neighbourhood income and neonatal, postneonatal and sudden infant death syndrome (SIDS) mortality in Canada, 1991-2005

BACKGROUND

Rates of infant mortality declined in Canada in the 1990s and 2000s, but the extent to which all socio-economic levels benefitted from this progress is unknown.

OBJECTIVES

This study investigated differences and time trends in neonatal, postneonatal and sudden infant death syndrome (SIDS) mortality across neighbourhood income quintiles among live births in Canada from 1991 through 2005.

METHODS

The Canadian linked live birth and infant death file was used, excluding births from Ontario, Yukon, Northwest Territories and Nunavut. Mortality rates for neonatal, postneonatal and sudden infant death syndrome (SIDS) were calculated by neighbourhood income quintile and period (1991-1995, 1996-2000, 2001-2005). Hazard ratios (HR) for neighbourhood income quintile and period were computed, adjusting for province of residence, maternal age, parity, infant sex and multiple birth.

RESULTS

In urban areas, for the entire study period (1991-2005), the poorest neighbourhood income quintile had a higher hazard of neonatal death (adjusted HR 1.24, 95% CI 1.15-1.34), postneonatal death (adjusted HR 1.58, 95% CI 1.41-1.76) and SIDS (adjusted HR 1.83, 95% CI 1.49-2.26) compared to the richest quintile. Postneonatal and SIDS mortality rates declined by 37% and 57%, respectively, between 1991-1995 and 2001-2005 whereas no significant change was observed in neonatal mortality. The decrease in postneonatal and SIDS mortality rates occurred across all income quintiles.

CONCLUSION

This study shows that despite a decrease in infant mortality and SIDS across all neighbourhood income quintiles over time in Canada, socio-economic inequalities persist. This finding highlights the need for effective infant health promotion strategies in vulnerable populations.

Cardiac ion channelopathies and the sudden infant death syndrome

The sudden infant death syndrome (SIDS) causes the sudden death of an apparently healthy infant, which remains unexplained despite a thorough investigation, including the performance of a complete autopsy. The triple risk model for the pathogenesis of SIDS points to the coincidence of a vulnerable infant, a critical developmental period, and an exogenous stressor. Primary electrical diseases of the heart, which may cause lethal arrhythmias as a result of dysfunctioning cardiac ion channels (“cardiac ion channelopathies”) and are not detectable during a standard postmortem examination, may create the vulnerable infant and thus contribute to SIDS. Evidence comes from clinical correlations between the long QT syndrome and SIDS as well as genetic analyses in cohorts of SIDS victims (“molecular autopsy”), which have revealed a large number of mutations in ion channel-related genes linked to inheritable arrhythmogenic syndromes, in particular the long QT syndrome, the short QT syndrome, the Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia. Combining data from population-based cohort studies, it can be concluded that at least one out of five SIDS victims carries a mutation in a cardiac ion channel-related gene and that the majority of these mutations are of a known malignant phenotype.

Scientific consensus forum to review the evidence underpinning the recommendations of the Australian SIDS and Kids Safe Sleeping Health Promotion Programme--October 2010

This paper summarises a 1-day scientific consensus forum that reviewed the evidence underpinning the Australian SIDS and Kids Safe Sleeping Health Promotion Programme. The focus was on each of the potentially modifiable risk factors for sudden unexpected deaths in infancy, including sudden infant death syndrome (SIDS) and fatal sleeping accidents. In particular infant sleeping position, covering of the face, exposure to cigarette smoke, room sharing, unsafe sleeping environments, bed sharing, immunisation, breastfeeding, pacifier use and Indigenous issues were discussed in depth. The participants recommended that future 'Reducing the Risk' campaign messages should focus on back to sleep, face uncovered, avoidance of cigarette smoke before and after birth, safe sleeping environment, room sharing and sleeping baby in own cot.

Racial differences in trends and predictors of infant sleep positioning in South Carolina, 1996-2007

This paper examines racial differences in trends and predictors of prone and lateral infant sleep positioning among South Carolina mothers and infants. Pregnancy Risk Assessment Monitoring System data were used to analyze linear trends in prone, lateral, and supine infant sleep positioning among 14,648 mother-infant pairs from 1996 to 2007. Logistic regression models were used to examine the predictors of prone and lateral positioning among 9,015 mother-infant pairs from 2000 to 2007. From 1996 to 2007, white infants experienced a reduction in both prone and lateral positioning and an increase in supine positioning (28.2-66.7%), while black infants had smaller decreases in prone and lateral positioning and a smaller increase in supine positioning (22.6-47.1%) than white infants. Compared to births in 2000-2005, births after the explicit recommendation that infants not be placed in the lateral sleep position (2006-2007) were associated with decreased odds of lateral positioning among white infants (odds ratio [OR]: 0.66; 95% confidence interval [CI]: 0.51, 0.87) but not among black infants. The significant predictors of white infants being placed in the prone position were different from the predictors for black infants. Additionally, with regard to lateral sleep positioning, more significant predictors were observed among white infants than black infants. These findings suggest that efforts are warranted to increase the prevalence of supine sleep positioning, especially among black infants. Race-specific programs may efficiently reduce non-supine sleep positioning to help narrow racial gaps in sudden infant death syndrome.

Risk factor changes for sudden infant death syndrome after initiation of Back-to-Sleep campaign

OBJECTIVE

To test the hypothesis that the profile of sudden infant death syndrome (SIDS) changed after the Back-to-Sleep (BTS) campaign initiation, document prevalence and patterns of multiple risks, and determine the age profile of risk factors.

METHODS

The San Diego SIDS/Sudden Unexplained Death in Childhood Research Project recorded risk factors for 568 SIDS deaths from 1991 to 2008 based upon standardized death scene investigations and autopsies. Risks were divided into intrinsic (eg, male gender) and extrinsic (eg, prone sleep).

RESULTS

Between 1991-1993 and 1996-2008, the percentage of SIDS infants found prone decreased from 84.0% to 48.5% (P < .001), bed-sharing increased from 19.2% to 37.9% (P < .001), especially among infants <2 months (29.0% vs 63.8%), prematurity rate increased from 20.0% to 29.0% (P = .05), whereas symptoms of upper respiratory tract infection decreased from 46.6% to 24.8% (P < .001). Ninety-nine percent of SIDS infants had at least 1 risk factor, 57% had at least 2 extrinsic and 1 intrinsic risk factor, and only 5% had no extrinsic risk. The average number of risks per SIDS infant did not change after initiation of the BTS campaign.

CONCLUSIONS

SIDS infants in the BTS era show more variation in risk factors. There was a consistently high prevalence of both intrinsic and especially extrinsic risks both before and during the Back-to-Sleep era. Risk reduction campaigns emphasizing the importance of avoiding multiple and simultaneous SIDS risks are essential to prevent SIDS, including among infants who may already be vulnerable.

A qualitative study of postpartum mothers' intention to smoke

BACKGROUND

Many women stop smoking during pregnancy. Factors associated with relapse are known, but no intervention prevents the return to smoking among pregnant women. The objective of this study was to determine why women return to smoking after prolonged abstinence during pregnancy by examining mothers' intention to smoke at the time of delivery and the perceptions that shape their intention.

METHODS

We conducted in-depth, semi-structured interviews during their postpartum hospital stay with 24 women who stopped smoking while pregnant. We asked participants whether they intended to resume smoking after pregnancy and why. Transcripts were analyzed using grounded theory-based qualitative methods to identify themes.

RESULTS

Participants ranged in age from 18 to 36 years, and 63 percent were white. Three themes emerged from the interviews with the mothers: 1) they did not intend to return to smoking but doubted whether they would be able to maintain abstinence; 2) they believed that it would be possible to protect their newborns from the harms of cigarette smoke; and 3) they felt that they had control over their smoking and did not need help to maintain abstinence after pregnancy.

CONCLUSIONS

Although most participants did not intend to resume smoking, their intentions may be stymied by their perceptions about second-hand smoke and by their overestimation of their control over smoking. Further study should quantify these barriers and determine their evolution over the first year after pregnancy with the goal of informing more successful, targeted interventions.

Swaddling: will it get babies onto their backs for sleep?

INTRODUCTION

The supine sleep position is recommended to reduce sudden infant death syndrome risk. Swaddling may improve adherence with supine placement.

AIM

To assess knowledge, attitudes, and practice regarding swaddling among adult caregivers of 0- to 3-month-old infants.

METHODS

Cross-sectional descriptive survey.

RESULTS

All 103 adults interviewed had swaddled their infant. Common reasons for swaddling included infant comfort and warmth. Almost 80% of those who swaddled their infant found it effective, 80% believed it to be comfortable, and ~90% believed swaddling to be safe. Parents who routinely used swaddling were more likely to find it effective and to place their infant supine when swaddled (P < .01).

CONCLUSIONS

Parents often use swaddling to comfort the infant, and most find it effective. Parents who routinely use swaddling are more likely to place their infant supine if swaddled. Swaddling may be a strategy for parents of infants who have difficulty sleeping in the supine position.

The molecular autopsy: should the evaluation continue after the funeral?

Sudden cardiac death (SCD) is one of the most common causes of death in developed countries, with most SCDs involving the elderly, and structural heart disease evident at autopsy. Each year, however, thousands of sudden deaths involving individuals younger than 35 years of age remain unexplained after a comprehensive medicolegal investigation that includes an autopsy. In fact, several epidemiologic studies have estimated that at least 3% and up to 53% of sudden deaths involving previously healthy children, adolescents, and young adults show no morphologic abnormalities identifiable at autopsy. Cardiac channelopathies associated with structurally normal hearts such as long QT syndrome (LQTS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and Brugada syndrome (BrS) yield no evidence to be found at autopsy, leaving coroners, medical examiners, and forensic pathologists only to speculate that a lethal arrhythmia might lie at the heart of a sudden unexplained death (SUD). In cases of autopsy-negative SUD, continued investigation through either a cardiologic and genetic evaluation of first- or second-degree relatives or a molecular autopsy may elucidate the underlying mechanism contributing to the sudden death and allow for identification of living family members with the pathogenic substrate that renders them vulnerable, with an increased risk for cardiac events including syncope, cardiac arrest, and sudden death.

Infant care practices related to sudden infant death syndrome in South Asian and White British families in the UK

In the UK, infants of South Asian parents have a lower rate of sudden infant death syndrome (SIDS) than White British infants. Infant care and life style behaviours are strongly associated with SIDS risk. This paper describes and explores variability in infant care between White British and South Asian families (of Bangladeshi, Indian or Pakistani origin) in Bradford, UK (the vast majority of which were Pakistani) and identifies areas for targeted SIDS intervention. A cross-sectional telephone interview study was conducted involving 2560 families with 2- to 4-month-old singleton infants enrolled in the Born in Bradford cohort study. Outcome measures were prevalence of self-reported practices in infant sleeping environment, sharing sleep surfaces, breast feeding, use of dummy or pacifier, and life style behaviours. We found that, compared with White British infants, Pakistani infants were more likely to: sleep in an adult bed (OR = 8.48 [95% CI 2.92, 24.63]); be positioned on their side for sleep (OR = 4.42 [2.85, 6.86]); have a pillow in their sleep environment (OR = 9.85 [6.39, 15.19]); sleep under a duvet (OR = 3.24 [2.39, 4.40]); be swaddled for sleep (OR = 1.49 [1.13, 1.97]); ever bed-share (OR = 2.13 [1.59, 2.86]); regularly bed-share (OR = 3.57 [2.23, 5.72]); ever been breast-fed (OR = 2.00 [1.58, 2.53]); and breast-fed for 8+ weeks (OR = 1.65 [1.31, 2.07]). Additionally, Pakistani infants were less likely to: sleep in a room alone (OR = 0.05 [0.03, 0.09]); use feet-to-foot position (OR = 0.36 [0.26, 0.50]); sleep with a soft toy (OR = 0.52 [0.40, 0.68]); use an infant sleeping bag (OR = 0.20 [0.16, 0.26]); ever sofa-share (OR = 0.22 [0.15, 0.34]); be receiving solid foods (OR = 0.22 [0.17, 0.30]); or use a dummy at night (OR = 0.40 [0.33, 0.50]). Pakistani infants were also less likely to be exposed to maternal smoking (OR = 0.07 [0.04, 0.12]) and to alcohol consumption by either parent. No difference was found in the prevalence of prone sleeping (OR = 1.04 [0.53, 2.01]). Night-time infant care therefore differed significantly between South Asian and White British families. South Asian infant care practices were more likely to protect infants from the most important SIDS risks such as smoking, alcohol consumption, sofa-sharing and solitary sleep. These differences may explain the lower rate of SIDS in this population.

Bed sharing and the risk of sudden infant death syndrome: can we resolve the debate?

OBJECTIVE

To conduct a meta-analysis on the relationship between bed sharing and sudden infant death syndrome (SIDS) risk.

STUDY DESIGN

Data from PubMed and Medline were searched for studies published after Jan 1, 1970. The search strategy included articles with the terms "sudden infant death syndrome," "sudden unexpected death," and "cot death" with "bed sharing" or "co-sleeping." To further specify the potential risk of bed sharing and SIDS, subgroup analyses were performed.

RESULTS

Eleven studies met inclusion criteria and were included in the final meta-analysis. The combined OR for SIDS in all bed sharing versus non-bed sharing infants was 2.89 (95% CI, 1.99-4.18). The risk was highest for infants of smoking mothers (OR, 6.27; 95% CI, 3.94-9.99), and infants <12 weeks old (OR, 10.37; 95% CI, 4.44-24.21).

CONCLUSIONS

Bed sharing is a risk factor for SIDS and is especially enhanced in smoking parents and in very young infants.

Effect of altered core body temperature on glottal closing force

OBJECTIVES

A basic function of the larynx is to provide sphincteric protection of the lower airway, initiated by a brain stem-mediated glottal closure reflex. Glottal closing force is defined as the measured pressure generated between the vocal folds during glottal closure. One of the factors thought to affect the glottal closure reflex is a variation in core body temperature.

METHODS

Four adult male Yorkshire pigs were used in this study. The subjects were studied under control conditions (37 degreesC), hyperthermic conditions (38 degrees C to 41 degrees C), and hypothermic conditions (36 degrees C to 34 degrees C).

RESULTS

We demonstrated that the glottal closing force increased significantly with an increase in core body temperature and also decreased significantly with decreased core body temperature. These results are supported by neurophysiological changes demonstrated by other studies in pups and adult dogs in response to altered core body temperatures. The mechanism for these responses is thought to reside centrally, rather than in the peripheral nervous system.

CONCLUSIONS

We hope that a better understanding of these aspects of glottal closure will alter the care of many patients with postanesthesia hypothermia and many sedated inmates and will also further enhance preventive measures needed to decrease the incidence of sudden infant death syndrome in overheated or febrile infants.

SIDS and other sleep-related infant deaths: expansion of recommendations for a safe infant sleeping environment

Despite a major decrease in the incidence of sudden infant death syndrome (SIDS) since the American Academy of Pediatrics (AAP) released its recommendation in 1992 that infants be placed for sleep in a nonprone position, this decline has plateaued in recent years. Concurrently, other causes of sudden unexpected infant death occurring during sleep (sleep-related deaths), including suffocation, asphyxia, and entrapment, and ill-defined or unspecified causes of death have increased in incidence, particularly since the AAP published its last statement on SIDS in 2005. It has become increasingly important to address these other causes of sleep-related infant death. Many of the modifiable and nonmodifiable risk factors for SIDS and suffocation are strikingly similar. The AAP, therefore, is expanding its recommendations from being only SIDS-focused to focusing on a safe sleep environment that can reduce the risk of all sleep-related infant deaths including SIDS. The recommendations described in this report include supine positioning, use of a firm sleep surface, breastfeeding, room-sharing without bed-sharing, routine immunization, consideration of a pacifier, and avoidance of soft bedding, overheating, and exposure to tobacco smoke, alcohol, and illicit drugs. The rationale for these recommendations is discussed in detail in this technical report. The recommendations are published in the accompanying "Policy Statement--Sudden Infant Death Syndrome and Other Sleep-Related Infant Deaths: Expansion of Recommendations for a Safe Infant Sleeping Environment," which is included in this issue (www.pediatrics.org/cgi/doi/10.1542/peds.2011-2220).

SIDS and other sleep-related infant deaths: expansion of recommendations for a safe infant sleeping environment

Despite a major decrease in the incidence of sudden infant death syndrome (SIDS) since the American Academy of Pediatrics (AAP) released its recommendation in 1992 that infants be placed for sleep in a nonprone position, this decline has plateaued in recent years. Concurrently, other causes of sudden unexpected infant death that occur during sleep (sleep-related deaths), including suffocation, asphyxia, and entrapment, and ill-defined or unspecified causes of death have increased in incidence, particularly since the AAP published its last statement on SIDS in 2005. It has become increasingly important to address these other causes of sleep-related infant death. Many of the modifiable and nonmodifiable risk factors for SIDS and suffocation are strikingly similar. The AAP, therefore, is expanding its recommendations from focusing only on SIDS to focusing on a safe sleep environment that can reduce the risk of all sleep-related infant deaths, including SIDS. The recommendations described in this policy statement include supine positioning, use of a firm sleep surface, breastfeeding, room-sharing without bed-sharing, routine immunizations, consideration of using a pacifier, and avoidance of soft bedding, overheating, and exposure to tobacco smoke, alcohol, and illicit drugs. The rationale for these recommendations is discussed in detail in the accompanying "Technical Report--SIDS and Other Sleep-Related Infant Deaths: Expansion of Recommendations for a Safe Infant Sleeping Environment," which is included in this issue of Pediatrics (www.pediatrics.org/cgi/content/full/128/5/e1341).

Decisions of black parents about infant bedding and sleep surfaces: a qualitative study

OBJECTIVE

The goal of this qualitative study was to examine factors influencing decisions by black parents regarding use of soft bedding and sleep surfaces for their infants.

METHODS

We conducted focus groups and individual interviews with black mothers of lower and higher socioeconomic status (SES). Mothers were asked about many infant care practices, including sleep surface and bedding.

RESULTS

Eighty-three mothers were interviewed, 73 (47 lower and 26 higher SES) in focus groups and 10 (7 lower and 3 higher SES) in individual interviews. The primary reason for using soft surfaces was infant comfort. Parents perceived that infants were uncomfortable if the surface was not soft. Many parents also interpreted "firm sleep surface" to mean taut; they were comfortable with and believed that they were following recommendations for a firm sleep surface when they placed pillows/blankets on the mattress as long as a sheet was pulled tautly over the pillows/blankets. The primary reasons for using soft bedding (including bumper pads) were comfort, safety, and aesthetics. In addition to using bedding to soften sleep surfaces, bedding was used to prevent infant rollover and falls, particularly for infants sleeping on a bed or sofa. Some parents used soft bedding to create an attractive space for the infant.

CONCLUSIONS

Many black parents believe that soft bedding will keep their infant safe and comfortable. There is much misunderstanding about the meaning of a "firm" sleep surface. Additional educational messages apparently are needed to change parental perceptions and practices.

Loss-of-function mutations in the KCNJ8-encoded Kir6.1 K(ATP) channel and sudden infant death syndrome

BACKGROUND

Approximately 10% of sudden infant death syndrome (SIDS) may stem from cardiac channelopathies. The KCNJ8-encoded Kir6.1 (K(ATP)) channel critically regulates vascular tone and cardiac adaptive response to systemic metabolic stressors, including sepsis. KCNJ8-deficient mice are prone to premature sudden death, particularly with infection. We determined the spectrum, prevalence, and function of KCNJ8 mutations in a large SIDS cohort.

METHODS AND RESULTS

Using polymerase chain reaction, denaturing high-performance liquid chromatography, and DNA sequencing, comprehensive open reading frame/splice-site mutational analysis of KCNJ8 was performed on genomic DNA isolated from necropsy tissue on 292 unrelated SIDS cases (178 males, 204 white; age, 2.9±1.9 months). KCNJ8 mutations were coexpressed heterologously with SUR2A in COS-1 cells and characterized using whole-cell patch-clamp. Two novel KCNJ8 mutations were identified. A 5-month-old white male had an in-frame deletion (E332del) and a 2-month-old black female had a missense mutation (V346I). Both mutations localized to Kir6.1's C-terminus, involved conserved residues and were absent in 400 and 200 ethnic-matched reference alleles respectively. Both cases were negative for mutations in established channelopathic genes. Compared with WT, the pinacidil-activated K(ATP) current was decreased 45% to 68% for Kir6.1-E332del and 40% to 57% for V346I between -20 mV and 40 mV.

CONCLUSIONS

Molecular and functional evidence implicated loss-of-function KCNJ8 mutations as a novel pathogenic mechanism in SIDS, possibly by predisposition of a maladaptive cardiac response to systemic metabolic stressors akin to the mouse models of KCNJ8 deficiency.

Breastfeeding and reduced risk of sudden infant death syndrome: a meta-analysis

CONTEXT

Benefits of breastfeeding include lower risk of postneonatal mortality. However, it is unclear whether breastfeeding specifically lowers sudden infant death syndrome (SIDS) risk, because study results have been conflicting.

OBJECTIVE

To perform a meta-analysis to measure the association between breastfeeding and SIDS.

METHODS

We identified 288 studies with data on breastfeeding and SIDS through a Medline search (1966-2009), review articles, and meta-analyses. Twenty-four original case-control studies were identified that provided data on the relationship between breastfeeding and SIDS risk. Two teams of 2 reviewers evaluated study quality according to preset criteria; 6 studies were excluded, which resulted in 18 studies for analysis. Univariable and multivariable odds ratios were extracted. A summary odds ratio (SOR) was calculated for the odds ratios by using the fixed-effect and random-effect inverse-variance methods of meta-analysis. The Breslow-Day test for heterogeneity was performed.

RESULTS

For infants who received any amount of breast milk for any duration, the univariable SOR was 0.40 (95% confidence interval [CI]: 0.35-0.44), and the multivariable SOR was 0.55 (95% CI: 0.44-0.69). For any breastfeeding at 2 months of age or older, the univariable SOR was 0.38 (95% CI: 0.27-0.54). The univariable SOR for exclusive breastfeeding of any duration was 0.27 (95% CI: 0.24-0.31).

CONCLUSIONS

Breastfeeding is protective against SIDS, and this effect is stronger when breastfeeding is exclusive. The recommendation to breastfeed infants should be included with other SIDS risk-reduction messages to both reduce the risk of SIDS and promote breastfeeding for its many other infant and maternal health benefits.

The factors contributing to the risk of sudden infant death syndrome

Sudden infant death syndrome (SIDS) is defined as the sudden death of an infant under one year of age which remains unexplained after a thorough case investigation, including performance of a complete autopsy, examination of the death scene and review of the clinical history. SIDS is one of the leading causes of infant mortality and occurs from the first month, until the first year of life for newborns and infants.The aim of this review was to identify and examine risk factors responsible for causing the sudden infant death and to propose certain measures in order to protect newborns and infants from sudden death. The potential factors that contribute to the occurrence of SIDS include inadequate prenatal care, low birth weight (<2499gr), premature infants, intrauterine growth delay, short interval between pregnancies and maternal substance use (tobacco, alcohol, opiates). Moreover, factors related to infant's sleep environment such as the prone or side sleeping position and thick coverlet increase the risk of sudden death in infants. Also, the combination of risk factors such as that of prone sleeping position and soft bed mattress are linked to a 20-fold increased risk of death. Finally, polymorphisms in the serotonin transporter gene (5-HTT), viral respiratory infections, long Q-T (responsible for the presence of fatal arrhythmia) are related to the SIDS.Literature review indicates that each individual risk factor contributes to the appearance of SIDS and the establishment of certain protective measures for parents and health professionals has reduced its prevalence. But the precise identification of the SIDS causes and how these contribute to the occurrence of sudden death in neonates and infants, remains a challenge for health professionals.

Where should my baby sleep: a qualitative study of African American infant sleep location decisions

BACKGROUND

African American infants are of higher risk for sudden infant death syndrome (SIDS) and accidental suffocation than other infants and are up to 4 times more likely to bedshare with their parents.

OBJECTIVE

To investigate, using qualitative methods, factors influencing African American parents' decisions regarding infant sleep location (room location and sleep surface).

METHODS

Eighty-three mothers participated in focus groups or individual interviews. Questions probed reasons for infant sleep location decisions and influences on decision making.

RESULTS

Most of the mothers in this study slept in the same room as their infant. Reasons for roomsharing included space, convenience, and safety. Mothers largely decided on infant sleep surface because of space for/availability of crib, comfort, convenience, and safety. Both roomsharing and bedsharing were often chosen to make feeding and checking on the infant more convenient. Mothers who chose not to bedshare cited privacy, concern that the infant would become attached to the parents' bed, and fears about suffocation. Mothers who chose to bedshare often cited the ability to maintain vigilance while asleep. Low-income mothers also used bedsharing as a defense against environmental dangers.

CONCLUSION

African American mothers in this study viewed both roomsharing and bedsharing as strategies to keep their infants safe. Efforts to encourage roomsharing without bed-sharing must address parental concerns about space for/ availability of a crib, convenience, infant and parent comfort, and infant safety.

Bed sharing among black infants and sudden infant death syndrome: interactions with other known risk factors

OBJECTIVE

Bed sharing has been associated with sudden infant death syndrome (SIDS) and may contribute to the racial disparity seen in infant mortality. It is unclear how bed sharing interacts with other factors to impact SIDS risk. We aimed to measure the effects of bed sharing on risk of SIDS in blacks and to determine whether the risk is modified by other characteristics of the sleep environment.

METHODS

Characteristics of 195 black infants who died of SIDS were compared with matched controls. The moderating influence of known SIDS risk factors on the effect of bed sharing on risk of SIDS was examined using logistic regression.

RESULTS

Almost half (47.4%) of the study population bed shared during the last/reference sleep (58% cases and 37% controls). Bed sharing was associated with 2 times greater risk of SIDS compared with not bed sharing. The deleterious effect of bed sharing was more pronounced with a soft sleep surface, pillow use, maternal smoking, and younger infant age. However, bed sharing was still associated with an increased risk of SIDS, even when the infant was not using a pillow or sleeping on a firm surface. The strongest predictors of SIDS among bed-sharing infants were soft sleep surface, nonuse of a pacifier, and maternal smoking during pregnancy.

CONCLUSIONS

Bed sharing is a common practice among black infants. It is associated with a clear and strong increased risk of SIDS, which is even greater when combined with other known risk factors for SIDS. This practice likely contributes to the excess incidence of SIDS among blacks, and culturally competent education methods must be developed to target this high-risk group.

Cardiovascular control during sleep in infants: Implications for Sudden Infant Death Syndrome

In infants the cardiorespiratory system undergoes significant functional maturation after birth and these changes are sleep-state dependent. Given the immaturity of these systems it is not surprising that infants are at risk of cardiorespiratory instability, especially during sleep. A failure of cardiovascular control mechanisms in particular is believed to play a role in the final event of Sudden Infant Death Syndrome (SIDS). The "triple risk model" describes SIDS as an event that results from the intersection of three overlapping factors: (1) a vulnerable infant, (2) a critical development period in homeostatic control, and (3) an exogenous stressor. This review summarises normal development of cardiovascular control during sleep in infants and describes the association of impaired cardiovascular control with the three overlapping factors proposed to be involved in SIDS pathogenesis.

Influence of prior advice and beliefs of mothers on infant sleep position

OBJECTIVES

To determine the relationship between the advice mothers receive about infant sleep position and the actual position they place their infants in to sleep and to understand modifiers of that relationship, especially beliefs about infant comfort and safety.

DESIGN

Cross-sectional, face-to-face interviews.

SETTING

Women, Infants, and Children centers in the United States from 2006 to 2008.

PARTICIPANTS

A total of 2299 predominantly African American mothers of infants younger than 8 months.

MAIN EXPOSURE

Advice received and beliefs about infant sleep position.

OUTCOME MEASURE

Usually supine infant sleep position.

RESULTS

Advice for exclusively supine infant sleep position from family (OR, 1.6; 95% CI, 1.17-2.17), doctors (OR, 2.28; 95% CI, 1.77-2.93), nurses (OR, 1.46; 95% CI, 1.15-1.84), or the media (OR, 1.54; 95% CI, 1.22-1.95) was associated with usually placing an infant supine to sleep. Additional sources of advice for exclusively supine position significantly increase the odds that an infant will be placed supine. Mothers who believe an infant is comfortable supine are more likely to place their infants on their backs to sleep (OR, 4.05; 95% CI, 2.51-6.53). Mothers who believe an infant will choke on its back are less likely to place their infants supine (OR, 0.36; 95% CI, 0.24-0.54).

CONCLUSION

Among predominantly African American mothers, increasing advice for exclusively supine sleep and addressing concerns about infant comfort and choking remain critical to getting more infants on their back to sleep.

Concurrent risks in sudden infant death syndrome

BACKGROUND

Despite improved education on safe sleep, infants are still exposed to multiple risks for sudden infant death syndrome (SIDS). Variability among health care providers continues to exist regarding knowledge of risk factors and the provision of education to caregivers.

OBJECTIVE

To enhance the content and delivery of SIDS risk-reduction initiatives by physicians and other health care providers and to provide them with a context for evaluating their discussions of risks and compensatory strategies, we sought to raise awareness of the frequency of risk factors in SIDS cases, patterns of co-occurrence, associations between modifiable and nonmodifiable risks, and the rarity of cases without risk.

DESIGN AND METHODS

In a population-based retrospective review of 244 (97%) New Jersey SIDS cases (1996-2000), we assessed the frequencies and co-occurrences of modifiable (maternal and paternal smoking, nonsupine sleep or prone status at discovery, bed-sharing, or scene risks) and nonmodifiable (upper respiratory infection or <37 weeks' gestational age) risks.

RESULTS

Nonsupine sleep occurred in 70.4% of cases with data on position (159 of 226). Thirteen cases were of infants who were discovered prone, with an increased positional risk to 76.1%, in which 87% contained additional risks. Maternal smoking occurred in 42.6% (92 of 216) of the cases with data on this risk, and 98% among those cases had additional risks. At least 1 risk was found in 96% of the cases, and 78% had 2 to 7 risks. Of the 9 of 244 risk-free cases (3.7%), 7 lacked data on 2 to 5 risks per case. On the basis of the complete data, only 2 (0.8%) of all 244 cases were risk free. When nonmodifiable risks were excluded, 5.3% of the cases met this definition.

CONCLUSIONS

Risk-free and single-risk SIDS cases are rare, and most contain multiple risks. Parent education should be comprehensive and address compensatory strategies for nonmodifiable risks.

SIDS: past, present and future

Despite the large reduction in SIDS mortality, which occurred in the early 1990s following the 'Back to Sleep' campaigns, SIDS remains the leading cause of death in the postneonatal age group. This paper describes the position in the 1980s, the contribution of the New Zealand Cot Death Study, what should be recommended and the current research priorities.

CONCLUSION

SIDS is preventable. Application of what we currently know could eliminate SIDS. The challenge is to find ways of implementing our knowledge.

Hazardous cosleeping environments and risk factors amenable to change: case-control study of SIDS in south west England

OBJECTIVES

To investigate the factors associated with sudden infant death syndrome (SIDS) from birth to age 2 years, whether recent advice has been followed, whether any new risk factors have emerged, and the specific circumstances in which SIDS occurs while cosleeping (infant sharing the same bed or sofa with an adult or child).

DESIGN

Four year population based case-control study. Parents were interviewed shortly after the death or after the reference sleep (within 24 hours) of the two control groups.

SETTING

South west region of England (population 4.9 million, 184 800 births).

PARTICIPANTS

80 SIDS infants and two control groups weighted for age and time of reference sleep: 87 randomly selected controls and 82 controls at high risk of SIDS (young, socially deprived, multiparous mothers who smoked).

RESULTS

The median age at death (66 days) was more than three weeks less than in a study in the same region a decade earlier. Of the SIDS infants, 54% died while cosleeping compared with 20% among both control groups. Much of this excess may be explained by a significant multivariable interaction between cosleeping and recent parental use of alcohol or drugs (31% v 3% random controls) and the increased proportion of SIDS infants who had coslept on a sofa (17% v 1%). One fifth of SIDS infants used a pillow for the last sleep (21% v 3%) and one quarter were swaddled (24% v 6%). More mothers of SIDS infants than random control infants smoked during pregnancy (60% v 14%), whereas one quarter of the SIDS infants were preterm (26% v 5%) or were in fair or poor health for the last sleep (28% v 6%). All of these differences were significant in the multivariable analysis regardless of which control group was used for comparison. The significance of covering the infant's head, postnatal exposure to tobacco smoke, dummy use, and sleeping in the side position has diminished although a significant proportion of SIDS infants were still found prone (29% v 10%).

CONCLUSIONS

Many of the SIDS infants had coslept in a hazardous environment. The major influences on risk, regardless of markers for socioeconomic deprivation, are amenable to change and specific advice needs to be given, particularly on use of alcohol or drugs before cosleeping and cosleeping on a sofa.

A summary of the Agency for Healthcare Research and Quality's evidence report on breastfeeding in developed countries

OBJECTIVES

This article summarizes the Agency for Healthcare Research and Quality's evidence report on the effects of breastfeeding on term infant and maternal health outcomes in developed countries.

EVIDENCE REPORT DATA SOURCES

Medline, CINAHL, Cochrane Library, bibliographies of selected reviews, and suggestions from domain experts were surveyed. Searches were limited to English-language publications.

EVIDENCE REPORT REVIEW METHODS

Eligible comparisons examined the association between differential exposure to breastfeeding and health outcomes. We assessed 15 infant and six maternal outcomes. For four outcomes, we also updated previously published systematic reviews. For the rest of the outcomes, we either summarized previous systematic reviews or conducted new systematic reviews; randomized and non-randomized comparative trials, prospective cohorts, and case-control studies were included. Adjusted estimates were extracted from non-experimental designs. The studies were graded for methodological quality. We did not draw conclusions from poor quality studies.

EVIDENCE REPORT RESULTS

We screened over 9,000 abstracts. Thirty-two primary studies on term infant health outcomes, 43 primary studies on maternal health outcomes, and 28 systematic reviews or meta-analyses that covered approximately 400 individual studies were included in this review. A history of breastfeeding was associated with a reduction in the risk of acute otitis media, nonspecific gastroenteritis, severe lower respiratory tract infections, atopic dermatitis, asthma (young children), obesity, type 1 and 2 diabetes, childhood leukemia, and sudden infant death syndrome. There was no relationship between breastfeeding in term infants and cognitive performance. There were insufficient good quality data to address the relationship between breastfeeding and cardiovascular diseases and infant mortality. For maternal outcomes, a history of lactation was associated with a reduced risk of type 2 diabetes, breast, and ovarian cancer. Early cessation of breastfeeding or no breastfeeding was associated with an increased risk of maternal postpartum depression. There was no relationship between a history of lactation and the risk of osteoporosis. The effect of breastfeeding in mothers on return-to-prepregnancy weight was negligible, and the effect of breastfeeding on postpartum weight loss was unclear.

EVIDENCE REPORT CONCLUSIONS

A history of breastfeeding is associated with a reduced risk of many diseases in infants and mothers. Future research would benefit from clearer selection criteria, definitions of breastfeeding exposure, and adjustment for potential confounders. Matched designs such as sibling analysis may provide a method to control for hereditary and household factors that are important in certain outcomes.

Infant sleeping environment in South-eastern Nigeria (sleeping place and sleeping position): a preliminary survey

Objective. To determine infant sleeping position/place and the factors associated with them in South-eastern Nigeria. Methods. this is a cross-sectional study on infant sleeping environment. Subjects were the mother/ infant pairs that attended the well baby clinics at the Institute of Child Health of the University of Nigeria Teaching Hospital, Enugu (ICH-UNTH), Mother of Christ Specialist Hospital (MCSH), Enugu and the Ebonyi State University Teaching Hospital (EBSUTH), Abakaliki. Results. Lying on the side was the most common (51.1%) and the least stable sleeping position. Only 36.6% of infants who slept in that position were likely to be found in the same position the following morning; lying supine was the most stable (74.1%). The difference in stability of sleeping positions was statistically significant (P < .01). Twenty six point seven percent of the mothers routinely lay their infants in prone position. On logistic regression, maternal parity was the only factor that was predictive of nonprone sleeping position (P = .01). Bed sharing, though common (66.9%), was more among the experienced (P = .03) and less educated mothers (P < .01). Conclusion. There is a high level of prone sleeping position and bed sharing among infants in this study site. The potential consequences of these are unclear. There is therefore a need to conduct local studies to clarify its implication.

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.

Medullary serotonin defects and respiratory dysfunction in sudden infant death syndrome

Sudden infant death syndrome (SIDS) is defined as the sudden and unexpected death of an infant less than 12 months of age that occurs during sleep and remains unexplained after a complete autopsy, death scene investigation, and review of the clinical history. It is the leading cause of postneonatal mortality in the developed world. The cause of SIDS is unknown, but is postulated to involve impairment of brainstem-mediated homeostatic control. Extensive evidence from animal studies indicates that serotonin (5-HT) neurons in the medulla oblongata play a role in the regulation of multiple aspects of respiratory and autonomic function. A subset of SIDS infants have several abnormalities in medullary markers of 5-HT function and genetic polymorphisms impacting the 5-HT system, informing the hypothesis that SIDS results from a defect in 5-HT brainstem-mediated control of respiratory (and autonomic) regulation. Here we review the evidence from postmortem human studies and animal studies to support this hypothesis and discuss how the pathogenesis of SIDS is likely to originate in utero during fetal development.

What is the mechanism of SIDS? Clues from epidemiology

The cause of sudden infant death syndrome (SIDS) is unknown. Many mechanisms have been postulated, although thermal stress, rebreathing of expired gases and infection/inflammation seem the most viable hypotheses for the causation of SIDS. Deaths from SIDS have reduced dramatically following the recommendation not to place infants to sleep prone. Epidemiological data have shown that prone sleeping position is more risky in winter, colder latitudes, higher altitudes, if the infant is unwell or has excessive bedding or clothing. This suggests prone sleeping position involves either directly or indirectly a thermal mechanism. SIDS caused by an infective/inflammatory mechanism might be associated with deaths occurring during the night. Rebreathing of expired gases, airway obstruction, long QT syndrome and other genetic conditions may explain a small number of sudden unexpected deaths in infancy.

Sids

INTRODUCTION

By definition, the cause of sudden infant death syndrome (SIDS) is not known. Observational studies have found an association between SIDS and several risk factors, including prone sleeping position, prenatal or postnatal exposure to tobacco smoke, soft sleeping surfaces, hyperthermia/overwrapping, bed sharing (particularly with mothers who smoke), lack of breastfeeding, and lack of soother use. The risk of SIDS is increased in families in which there has been a prior sudden infant death.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical question: What are the effects of interventions to reduce the risk of SIDS? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2007 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 28 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review, we present information relating to the effectiveness and safety of the following interventions: advice to avoid prone sleeping; advice to avoid tobacco-smoke exposure; advice to avoid soft sleeping surfaces; advice to avoid overheating or overwrapping; advice to avoid bed sharing; advice to breastfeed; advice to promote soother/pacifier use; and advice to promote room sharing (without bed sharing).

Infant sleep position: a randomized clinical trial of an educational intervention in the maternity ward in Porto Alegre, Brazil

BACKGROUND

Few studies in Brazil have been published about sudden infant death syndrome (SIDS), and none has addressed the mother's orientation about placing the infant to sleep in the supine position. The aim of this study was to evaluate the effect on mothers of an individual educational intervention in the maternity ward about infant sleep position.

METHODS

A randomized clinical trial was conducted with a study sample of 228 mother-infant pairs assigned to an intervention or a control group. The intervention consisted of an individual orientation session at the maternity ward, at which folders and an oral explanation were given to mothers at discharge about the importance of the supine position as a preventive measure for SIDS. The outcome was the sleeping position at 3 months of age assessed during a home visit. The variables with p< 0.2 at a bivariate analysis were included in a logistic regression model.

RESULTS

Among mothers in the intervention group, 42.9 percent put their infants to sleep in a supine position at the 3-month visit, compared with 24 percent of mothers in the control group (p = 0.009). In a multivariate analysis, the intervention at the hospital was the only variable that influenced maternal practices with respect to infant sleep positioning (OR 2.22; 95% CI 1.17-4.19).

CONCLUSIONS

An individual educational session in the maternity ward about infant sleep position significantly increased the prevalence of supine position for sleeping in the infant's third month. Nevertheless, the intervention was not sufficient to guarantee that most mothers would put their infants to sleep in the recommended position.

Sleep environment risk factors for sudden infant death syndrome: the German Sudden Infant Death Syndrome Study

OBJECTIVE

Our goal was to investigate the risk factors for sudden infant death syndrome in the infants' sleep environment for a population in which few infants sleep prone as a result of education campaigns.

METHODS

This was a population-based sudden infant death syndrome case-control study over 3 years (1998-2001) in Germany.

RESULTS

There were 333 sudden infant death syndrome cases and 998 matched controls. Although only 4.1% of the infants were placed prone to sleep, those infants were at a high risk of sudden infant death syndrome. Those who were unaccustomed to sleeping prone were at very high risk, as were those who turned to prone. Bed sharing (especially for infants younger than 13 weeks); duvets; sleeping prone on a sheepskin; sleeping in the house of a friend or a relative (compared with sleeping in the parental home); and sleeping in the living room (compared with sleeping in the parental bedroom) increased the risk for sudden infant death syndrome; pacifier use during the last sleep was associated with a significantly reduced risk of sudden infant death syndrome.

CONCLUSIONS

This study has clarified the risk factors for sudden infant death syndrome in a population where few infants sleep prone. This study supports the current recommendations of the American Academy of Pediatrics. This study has identified several novel risk factors for sudden infant death syndrome: an increased risk if the infants sleeps outside the parental home, death in the living room, and the high risk when sleeping prone on a sheepskin; however, because the numbers of cases in these groups are small, additional studies are needed to confirm these findings.

Does breastfeeding reduce the risk of sudden infant death syndrome?

BACKGROUND

In the last 20 years, the prevention campaigns to reduce the risk of sudden infant death syndrome were very successful. In some countries the advice to breastfeed is included in the campaigns' messages, but in other countries it is not.

OBJECTIVE

To examine the association between type of infant feeding and sudden infant death syndrome.

METHODS

The German Study of Sudden Infant Death is a case-control study of 333 infants who died of sudden infant death syndrome and 998 age-matched controls.

RESULTS

A total of 49.6% of cases and 82.9% of controls were breastfed at 2 weeks of age. Exclusive breastfeeding at 1 month of age halved the risk, partial breastfeeding at the age of 1 month also reduced the risk of sudden infant death syndrome, but after adjustment this risk was not significant. Being exclusively breastfed in the last month of life/before the interview reduced the risk, as did being partially breastfed. Breastfeeding survival curves showed that both partial breastfeeding and exclusive breastfeeding were associated with a reduced risk of sudden infant death syndrome.

CONCLUSIONS

This study shows that breastfeeding reduced the risk of sudden infant death syndrome by approximately 50% at all ages throughout infancy. We recommend including the advice to breastfeed through 6 months of age in sudden infant death syndrome risk-reduction messages.