The researchers identified over 41,000 mothers in a Danish registry who had a baby born with major anomalies between 1979 and 2010. They matched each mother with 10 mothers of the same age who had unaffected babies the same year, then followed the two groups to 2014 to compare mortality. After a median follow-up of 21 years, 3.1 per cent of the mothers of infants with anomalies had died at a mean age of 49, compared to 2.4 per cent of the mothers whose children were not affected.
“I think the results are troubling,” says lead investigator Dr. Eyal Cohen, a pediatrician at SickKids Hospital. “The absolute risk to a given individual is not high, but on a population level, a small increased risk multiplied by thousands of people is much more substantial.” BLOOM interviewed Dr. Cohen.
BLOOM: Why was there a need for this study?
Eyal Cohen: Parents who look after kids with serious health issues report that it’s extremely stressful, and we know from previous surveys of mothers in particular—because they’re generally the primary caregiver—that they report their own physical and mental health as poor. But no one had ever looked at mortality.
BLOOM: In your study you reference research showing that this type of parenting can cause premature cell aging.
Eyal Cohen: Yes. One of the papers I cite was from a Nobel Laureate who was the first person to discover telomeres and their association with premature aging of cells in the body. When I went back to read her original research, I was surprised to find she was studying mothers of children with severe health issues. So there’s a biological basis for this and also reports from people of poorer health outcomes.
BLOOM: What kind of conditions did the children in the study have?
Eyal Cohen: We looked at two groups: those with anomalies affecting one organ system like heart disease and those with multiple anomalies, like a child with Down syndrome and a heart defect. The reason we decided to focus on congenital anomalies is that they’re clear cut—you either have them or you don’t. They’re easily diagnosable and happen at a fixed period of time, whereas disability can be more gradual. We wanted to test our assumption that caregiving stress was associated with higher mortality risk. We anticipated that mothers looking after sicker children would have more of this outcome. But I have no reason to believe that the findings wouldn’t be generalizable to a broader group with disabilities.
BLOOM: What was the main finding?
Eyal Cohen: We found there was an increased risk of dying of 27 per cent in mothers who gave birth to babies with major anomalies, compared with mothers of the same age, with the same number of previous births, who had unaffected children born the same year. When we adjusted for factors such as the mother having health problems herself, the difference was slightly smaller, a 22 per cent increase. The increased risk of dying in mothers with more severely affected babies was 31 per cent. One thing that surprised us was that we saw this effect even within the first 10 years after delivery, and the same effect continued downstream.
BLOOM: What types of diseases did the mothers die of?
Eyal Cohen: There wasn’t one cause of death. We did find a fairly substantial increased risk of dying of a heart attack, and heart disease has been associated with chronic stress. The mothers of children with anomalies had a 97 per cent increased risk of dying of a heart attack compared to the other group. There was only a slight increase in risk of cancer, which is not thought to be triggered by stress.
BLOOM: So what does this mean for mothers raising children with complex needs?
Eyal Cohen: Their relative risk of dying of a heart attack is almost twice as high, but at an absolute level, heart attacks are not common in young women. So the overall risk isn’t huge. If a woman has a child with a major anomaly, it’s not likely that she’s going to die prematurely. But on a population level, a small increased risk, multiplied by thousands of people, is much more substantial.
BLOOM : Your study says that the clinical importance of the increased risk of death is uncertain.
Eyal Cohen: This is one paper and I don’t want people to think causality is proven with one paper. The evidence is compelling and troubling.
We often put the words maternal and child health together, and we know that if mothers are healthier, it will make their children healthier. But we spend a lot less time, particularly in health policy and support, on the concept that an unhealthy child can affect the health of a parent and family.
We don’t have a lot of programs and supports and funding dedicated to these families. I look after many families of children with disabilities and other complex health needs and it’s not infrequent that we have to address the parents’ health, and that is not easy to do. We need to see if what’s true in Denmark is true in Canada, and develop evidence-based interventions to see if we can attenuate these outcomes.
BLOOM: Your study notes that families of children with health problems in Denmark have extensive health and social supports.
Eyal Cohen: You’re correct. I would expect you would see the effect more here, where the supports are generally not as great.
BLOOM: You refer to research of senior caregivers that shows that sometimes the caring protects the health of the caregiver. Why would this be different in parent caregivers?
Eyal Cohen: I think there’s a substantial difference in how we think about caregiving in seniors as opposed to pediatrics. When an elderly person gets ill, their caregivers generally have a choice. They can care for their loved one at home or put them in a facility. But with children, we have a societal expectation that they’re raised by their families—for all the right reasons—and it’s rare that a parent of a disabled or very ill child puts them into care. Mothers do most of the caregiving and they don’t have choices in these matters—that’s an important part of it.
The duration of caregiving is also much longer. And there’s extraordinary trauma associated with the discordance between either societal or personal expectations of what caregiving of a child will be like. It’s not a societal expectation that one will raise a chronically ill or dependent child.
There are also differences in that generally the scenarios we studied were highly unexpected. Most women go into a pregnancy expecting a healthy birth. But while there can be a catastrophic event like a stroke for seniors, often there’s a bit of forewarning that a dependent older person’s health is declining.
BLOOM: It’s frustrating as a parent to know of these increased health risks, but not see more research into how we can reduce the risks.
Eyal Cohen: Some of the questions we discussed still need to be teased out—mechanistically, locally or contextually. But I think I agree with you that the direction of this work needs to move on the intervention side.
We need to look at more intensive psychosocial and mental health supports, especially during times of extreme stress—at diagnosis or transition from hospital to home and across different life stages. We are trialing mindfulness interventions for families being discharged from our NICU after months of being in an extremely stressful environment.
Caregivers are so busy that it wouldn’t surprise me if they don’t have time to get their own primary health care and screening. Do we need an adult health clinic embedded at Holland Bloorview or SickKids, where parents will be seen at the same time their children are seen?
BLOOM: That sounds like a fabulous idea! It’s similar to the program at SickKids for teen mothers where they combine health appointments for the mother and baby.
Eyal Cohen: We also need to look at high-level policy. There’s work showing that families of children with complex needs get poorer over time. We need to rethink parental leave and disability taxation policy.
BLOOM: What advice would you give mothers reading the study?
Eyal Cohen: I look after many of these kids and there’s a subgroup of parents who have extraordinary resiliency. It blows me away how resilient many families are. I would advocate that we use strength-based approaches to thinking about this. How dedicated a family is to a child can be a good and extra positive experience. But particularly for those families who are struggling and find it a battle, they need to be attuned to their own health and seek out health care. At this point, unfortunately, our system isn’t set up to screen parents for that. Until that happens, caregiving mothers need to be attentive to both their stress and their health.