From Childhood Trauma, Adult Tumors
Groundbreaking MED study links child abuse and fibroid tumors
Among children who have known the trauma of child abuse, the list of potential side effects is long: bad dreams and bed-wetting. Stuttering and substance abuse. Anxiety, aggression, withdrawal, and chronic difficulties in school.
But a new study by the Boston University School of Medicine suggests that child physical and sexual abuse can also have implications for the health and biological function of abuse victims far into adulthood. The groundbreaking study, which followed more than 60,000 women over 16 years, found that those who were abused as girls were more likely to develop uterine fibroids decades later as adults.
Fibroids are benign tumors in the uterus that range from the size of a pea to the size of a cantaloupe. They can trigger a host of health problems, including chronic heavy bleeding, anemia, pelvic and back pain, bladder and bowel conditions, and problems with fertility and conception.
In the public health arena, fibroids are largely overshadowed by more deadly cancerous tumors. But fibroids do pose a major public health issue because of the sheer number of women who have them: as many as 77 percent of women develop fibroids during their reproductive years, according to some studies, and the disease is known to disproportionally affect black women. Because fibroids can be asymptomatic—and because even women suffering severe cases tolerate the symptoms for periods of time—many cases go undiagnosed. Fibroid tumors are also the leading cause of hysterectomies in the United States, and as it turns out, this country has one of the highest rates of hysterectomy in the industrialized world—roughly one in four women undergoes the procedure by age 60.
Could the growth of these tumor cells in some women actually be rooted in childhood trauma? The close correlation stunned even study author Renee Boynton-Jarrett, a MED assistant professor of pediatrics. Compared with those who reported no abuse as children, women who said they had been abused were between 8 percent and 36 percent more likely to develop fibroids. That risk increased steadily the longer a child was exposed to abuse and the more severe the abuse became. And perhaps most striking of all, the data showed that the intervention of a supportive adult in an abused child’s life seemed to blunt the risk of developing fibroids down the line.
“I think this study has an important public health message,” says Boynton-Jarrett, who is also a pediatrician at Boston Medical Center. “While we might not be able to prevent every episode of childhood abuse, we can respond to children who we know have experienced abuse by making sure they have a supportive and nurturing environment.” At the same time, epidemiologists say, Boynton-Jarrett’s study has implications for future research and treatment of fibroids: as noninvasive treatment methods are developed that may be more effective during earlier stages of the disease, understanding those at high risk for fibroids might help determine who would benefit from screening.
BU Today spoke to Boynton-Jarrett about the study, which appeared in the January 2011 issue of the journal Epidemiology.
BU Today: How did you become interested in this area of research?
Boynton-Jarrett: It began when I was in grad school, at the Harvard School of Public Health. I was interested in how exposures to adversities in childhood could affect health across your life course. Fibroids was an area that was underresearched, but is very common among women.
How common are fibroids?
It’s not known exactly how common fibroids are in women, because they can be asymptomatic. We know that the prevalence of symptomatic fibroids is about 25 percent of women of reproductive age. But we don’t know the prevalence of fibroids that are asymptomatic, because they aren’t brought to medical attention.
What is it about the way fibroids develop that made you suspect a connection to childhood abuse?
One of the things we know about fibroids is that they’re hormonally responsive tumors. In other words, their cell growth is influenced by hormones in the body, such as estrogen. So I became very interested in ways in which stress influenced hormones such as estrogen, and how that might have an impact on fibroid growth.
How does stress affect hormones?
What we know about stress, both acute stressors and chronic stressors that are experienced over time, is that it can influence the way the body regulates hormones. And it can particularly affect organ systems that are sensitive to hormones, which would include the uterus. Stress can cause what we might call a dysregulation, or impaired regulation, of hormones in the body.
What are some of the other interesting findings of the study?
We realized that one of the biases in our study might be that someone who has fibroids, because they have a medical condition, might feel that their childhood was more problematic than someone else’s. So we also did a small sub-study looking just among women who had no diagnosis of fibroids at the time they answered our questionnaire about abuse in childhood, and then we looked forward over several years at reporting of fibroids in the future. And what we found was that among those women as well, there was an association between childhood exposure to violence and the risk for future onset fibroids.
How can other factors besides abuse be ruled out?
At the end of the day, this is a hard association to show, in part because there can be so many additional factors that perhaps we haven’t measured carefully or well enough. We know that when we ask people about experiences of childhood abuse, there’s a risk of underreporting those experiences, so we might not be capturing everyone. We know there are many factors associated with childhood adversities that can harm health that we can’t control for perfectly. So there are lots of challenges in this type of study. But when we saw this graded association, with increasing severity of abuse and increasing risk for fibroids, it provided even further strength and weight to the evidence that there is a real association between the exposure to abuse and the risk for fibroids.
What are the broader implications of your finding that support from a caring adult could lower the risk of developing fibroids for abused girls later in life?
A lot of times when we talk about childhood adversities, we talk about the concept that some children are resilient, or more resilient. We tend to think about resilience in terms of a child’s mental and emotional well-being. I think what’s important here is that the social support some children received buffered the negative impact on a biological outcome. We don’t know the exact mechanism by which that happened, but it suggests that resilience is more complex than just a state of being, and that it might operate on a biological level as well.