Worldwide study on sudden infant death finds factors associated with poverty and racism are more important than bedsharing

Last week, we published our novel study, “Sudden Infant Death and Social Justice: A Syndemics Approach,” showing that bedsharing – which has been the main focus of many interventions – is not the primary risk behind sudden infant death.

Instead, factors associated with poverty and racism have much more to do with Sudden Unexplained Infant Death (SUID), which includes suffocation, and its subset, SIDS (Sudden Infant Death Syndrome). Looking at populations around the world and the known risk factors for sudden infant death, we found that the vast majority of infants dying are from poor or marginalized populations, especially people who have experienced historical trauma. On the other hand, many wealthy and privileged populations have high rates to moderate rates of bedsharing,like Asian Americans and Swedes, yet have some of the lowest rates of SUID/SIDS in the world.

We used the medical anthropological theory of syndemics to help explain how social inequities that may be driven by historical forces and their legacies lead to the clustering of these risk factors, which ultimately results in higher death rates in poor and marginalized populations. It is important to view SUID/SIDS in the greater context of the growing field of social determinants of health.

Right now, American Indian/Alaskan Natives have the rates of SUID/SIDS in the world, with US Blacks a close second. We looked at a wide range of populations from around the world for which data was publicly available, from Australian Aborigines, New Zealand Māori, to Japanese, Dutch, Swedes, as well as all the US ethnic and racial groups. For each group, we looked at known risk factors for sudden infant death, including bedsharing.

When we looked at all the other risk factors beyond bedsharing, these populations have many more of these risk factors, whereas the wealthy and privileged populations have few to none. These risk factors tend to cluster where there is poverty and oppression: smoking, alcohol and substance abuse, preterm birth, formula feeding, poor access to prenatal care, and infants sleeping on the stomach. A lot of sudden infant death risks overlap with one another. And if these risk factors combine with bedsharing, bedsharing can become dangerous, especially if it’s on a sofa and not on a bed, which is also more likely in some of these populations. Even sleeping on the stomach is indirectly related to poverty because it’s more likely to occur in formula feeding infants, who in turn are more likely to be poor. Sleeping on the stomach is something a bedsharing breastfeeding infant wouldn’t do because it’s not a biologically normal position for that infant. Bedsharing formula-feeding babies are more likely to assume hazaradous positions, according to videographic data, and sleep lab data show that bedsharing breastfeeding infants aren’t seen sleeping on their stomachs.

Compared to the general population, lack of prenatal care was something very common to all the SUID/SIDS cases in the United States, even among the groups with the lowest rates of death and other risk factors. Poverty, housing instability, and insurance issues, play a large role in access to prenatal care. If a woman has to forgo pay to leave her low wage job to get to a prenatal appointment, spending the hours on public transportation, chances are she’s not getting there at all: She’s is not getting her high blood pressure or diabetes managed to prevent that preterm birth, or hearing the message about not sleeping on a sofa or putting baby on his back, or getting help with smoking cessation.

Currently 41% of US kids are in poverty or near poverty (per Columbia University’s National Center for Children in Poverty). High sudden infant death cuts across all US races, but racial and ethnic minorities who have suffered historical trauma experience the highest rates. Those at highest risk probably experience a cluster of risk factors, including pervasive racism and structural violence, aggressive marketing of infant formula. And research shows that hospitals that serve Black zip codes were more likely provide care that was not evidence based with respect to breastfeeding.

While the issue of improving overcoming the world’s worse SUID rates may seem daunting, some of these problems are low-hanging fruit. Bedsharing combined with smoking is extremely hazardous, and while it’s difficult to change bedsharing behavior as it’s a strong biological imperative, we can affect smoking by raising tobacco prices.

We know from research in Europe that raising tobacco prices markedly lowers infant mortality rates, immediately after implementation and in the year that follows, too. Even the CDC recommends raising tobacco prices. If tobacco prices were higher and people quit, sleeping with your baby would be safer. We could markedly decrease infant death rates next year by increasing tobacco prices today and providing nonjudgmental support for quitting smoking. That would make much more of a difference to infant mortality rates than all the scary bedsharing ads would ever do.

Similarly, breastfeeding is an issue responsive to ready structural change. US Black women are much more likely to experience hospital care that undermines breastfeeding, and they are more likely to have jobs that make it very difficult for them to continue to breastfeed, and that can and is changing with targeted interventions to make more such hospitals Baby-Friendly in the US. Eliminating aggressive formula marketing that violates the WHO Code of the Marketing of Breast-Milk Substitutes will reduce another barrier. Women want to breastfeed, but are sent home with little knowledge and a bag full of ready-to-feed formula, doomed to fail and become committed formula consumers.

Aggressive marketing of infant formula is a problem all women all over the world undermining women’s ability to breastfeed and costing many infant lives. Many countries, especially the US, allow this to run rampant. Families and individual doctors can’t fight this alone. This is a political problem. We saw this recently at the May 2018 World Health Assembly, where the US faced down other countries in order to continue this unethical practice that is costing the lives of US infants—and mothers—and infant and maternal lives around the globe.

Ultimately, our study shows that we need structural change. Even white US infants are dying of SIDS nearly as often as the Māori in New Zealand, which were the highest in the world until recently. Why? Likely because of the pervasive child poverty rate in the US. We now see poverty affecting SIDS rates in the UK, too, where a report just showed that SIDS is rising there for the first time in 3 years, worst in the poorest areas.

The bigger problems in the US lie with fixing the social safety net, especially for expectant families and families with young children. Significant success in lowering of infant death rates among poor infants of color was achieved in a home visiting program among low-income pregnant and post-partum Medicaid recipients in Michigan. This is a small doable solution.

The US can look to New Zealand if we want to tackle lowering our staggering infant death rates. New Zealand is rapidly bringing down its sudden infant death rates from the world’s highest, having led the world because the extremely high death rates in their indigenous Māori population. Māori tend to be the poorest people in New Zealand, a result of historical trauma at the hands of European settlers. They have extremely high smoking rates and high bedsharing rates, and this combination likely contributed to the high infant death rates. But the government, working with the Māori leaders, managed to reduce the disparities. Nearly every Māori woman gets excellent prenatal care. They developed a Māori inspired woven bassinet called a Wahakura, which can be used on the bed. The Wahakura helps keeps mothers and babies close and makes breastfeeding easier but limits the risk of death with co-sleeping. Breastfeeding rates are very high throughout the country because nearly every hospital is Baby-Friendly, although they are still much lower among Māori. New Zealand also recently instituted a 40% step-wise tobacco tax. Death rates are beginning to plummet. The government is bilingual, English and Māori, and they are trying hard to be more inclusive and address past historical trauma. So, in New Zealand we see what is possible with structural change and work toward racial reconciliation and collaboration.

The question is, does the US have the political will to prevent its own infants from dying? This is something that goes far beyond individual mothers’ or health care providers. Larger solutions regarding income inequality, universal health insurance, and paid family leave, as well as repairing the legacies of historical trauma are needed.

Until we address those factors, and their underlying root causes, which are poverty and racism, we are unlikely to make progress with infant mortality. In the US, we see gains in breastfeeding and smoking cessation, but these gains are on the way to being erased by the rising childhood poverty rate, giving us the highest sudden infant death rate in the industrialized world, and the only one which is not going down appreciably. The US has an infant mortality rate of 5.9 per 1000, while the rest of developed world has a much lower at 5.5. That is likely to only get worse unless we implement different policies.

Medical organizations must act beyond the exam room for our patients’ health. Structural and policy remedies, not just individual advice, are needed to bring down infant death rates. These are ultimately political problems with political solutions.

Melissa Bartick, MD, MSc is an internist at Cambridge Health Alliance and Assistant Professor at Harvard Medical School. 

Cecília Tomori, PhD, is Assistant Professor of Anthropology, Parent-Infant Sleep Lab, Durham University, UK.

Posts on this blog reflect the opinions of individual ABM members, not the organization as a whole.