EPITalk: Behind the Paper
This stimulating podcast series from the Annals of Epidemiology takes you behind the scenes of groundbreaking articles recently published in the journal. Join Editor-in-Chief, Patrick Sullivan, and journal authors for thought-provoking conversations on the latest findings and developments in epidemiologic and methodologic research.
EPITalk: Behind the Paper
Exploring the Link between Iron Deficiency Anemia & Severe Maternal Morbidity
Dr. Nansi Boghossian deep dives into her research findings on the alarming connection between iron deficiency anemia and severe maternal morbidity risk among pregnant individuals. Her study, “Association between iron deficiency anemia and severe maternal morbidity: A retrospective cohort study,” can be found in the December 2024 (Vol. 100) issue of Annals of Epidemiology.
Read the full article here:
https://www.sciencedirect.com/science/article/abs/pii/S1047279724002485
Episode Credits:
- Executive Producer: Sabrina Debas
- Technical Producer: Paula Burrows
- Annals of Epidemiology is published by Elsevier.
Hello, you're listening to EPITalk: Behind the Paper, a monthly podcast from the Annals of Epidemiology. I'm Patrick Sullivan, Editor-in-Chief of the journal, and in this series we take you behind the scenes of some of the latest epidemiologic research featured in our journal. Today we are here with Dr. Nansi Boghossian to discuss her article "Association Between Iron Deficiency, anemia and Severe Maternal orbidity: A retrospective cohort study." You can read the full article online in the December 2024 issue of the journal at wwwannalsofepidemiologyorg. Dr Nancy Boghossian is an associate professor in the Department of Epidemiology and Biostatistics at the University of South Carolina. Her research focuses on investigating factors influencing maternal and neonatal health outcomes. She's particularly interested in healthcare access, quality and state policies and how these factors result in racial and ethnic disparities in maternal and newborn outcomes. Dr Boghossian, thank you for joining us today.
Nansi Boghossian:Thank you for having me. I'm looking forward to this.
Patrick Sullivan:So I wonder if you could start just by briefly describing the purpose of the study. What was the research question that you were trying to answer?
Nansi Boghossian:Yes, sure. So we set out to examine the association between iron deficiency anemia and severe maternal morbidity during the delivery, hospitalization and up to one year postpartum.
Patrick Sullivan:Okay, and so you mentioned a couple of terms there that everybody might not be familiar with. Can you just sort of explain what is iron deficiency anemia, and how does it relate to severe maternal morbidity?
Nansi Boghossian:Sure. So iron deficiency anemia is basically a condition where the body does not have enough iron in order to produce hemoglobin, and that's the protein in red blood cells that carries oxygen, and this usually leads to symptoms like fatigue, weakness, pale skin, shortness of breath and dizziness. Severe maternal morbidity is the unexpected outcomes of labor and delivery that result in short-term or long-term outcomes for the mom, and these can include conditions such as sepsis, acute renal failure or eclampsia, and iron deficiency anemia has been linked to increased risks of multiple adverse maternal and fetal outcomes, including placental abruption, hemorrhage shock, intensive care unit admission for the mom, low birth weight and preterm delivery for the newborn. But there has been no, or very little, examination of the association between iron deficiency anemia and SMM or severe maternal morbidity, and so we set out to examine this in this current paper.
Patrick Sullivan:Great. So, given that question, can you walk us through your study design basically how you organized the data and conceived of the analysis, and say a little bit about why you chose that particular analytic method?
Nansi Boghossian:Sure.
Nansi Boghossian:So this was again a retrospective, population-based cohort study that used birth and fetal death certificates that were linked to maternal and newborn hospital discharge data, and the states that were included were Michigan, oregon and South Carolina from 2008 to 2020.
Nansi Boghossian:And these linkages of the birth and fetal death certificates are done usually by state health departments linkages to the hospital discharge data with some states routinely performing this linkage and others performing it by request from the investigators. There are very well-established methods in order to conduct these linkages and the linkage rate is estimated between more than 95%. So the data were available for the delivery, hospitalization and up to one year postpartum. Our primary outcomes looked at blood transfusion and non-transfusion SMM, and for that we used modified Poisson regression models in order to examine the adjusted relative risks and 95% confidence intervals. We also estimated the population attributable risk for 10,000 births and we adjusted for a variety of factors, including birth year, the state of residence, insurance type, education, race and ethnicity, the adequacy of prenatal care utilization and the obstetric comorbidity index, and that's an index that includes 27 risk factors for SMM that are each scored and ranked by their relative significance.
Patrick Sullivan:Great. So, after you implemented these methods, what were the main findings from your study and what do you think is important from a public health point of view to emphasize about your findings?
Nansi Boghossian:So we had almost two and a half million individuals and the rate of iron deficiency anemia was around 10.3% and the rate increased over time, particularly among Black individuals. And we found that individuals with iron deficiency anemia had higher rates of blood transfusion and non-transfusion SMM than those without iron deficiency anemia. The risk of blood transfusion was 8.2, and that's the adjusted relative risk, and for non-transfusion, the adjusted relative risk was almost twofold among individuals with iron deficiency anemia compared to those without iron deficiency anemia. The relative risks were still elevated at one year postpartum and so for non-transfusion SMM they were 30% higher among individuals with iron deficiency anemia. And also we found differences by race and ethnicity. So iron deficiency anemia was associated with approximately twofold increasing the risk of SMM across all groups, but Black individuals had the highest population attributable risk for both blood transfusion and SMM. For SMM indicators, the individuals with iron deficiency anemia had more than twofold increased risk for sepsis, for disseminated intravascular coagulation, tracheostomy and respiratory distress syndrome.
Patrick Sullivan:So you mentioned some maternal outcomes like disseminated intravascular coagulation or DIC sepsis. Are these sort of transient or easy to treat things, or are these pretty serious health concerns for the mother?
Nansi Boghossian:These are serious health problems for the mom and moms usually end up being hospitalized for them for a couple days. So again, these are serious indicators that cause adverse outcomes for the mother.
Patrick Sullivan:Can you give us an idea of how your findings compared with the previous literature on this subject? Is this a new finding confirming a previous finding in a new population? How would you put this in context of the existing literature?
Nansi Boghossian:Yes, so there's been a couple studies that have examined general anemia in relation to SMM outcomes. General anemia meaning looking at all nutritional anemias, sometimes excluding hereditary anemias, but our paper focused specifically on iron deficiency anemia. Our findings are in line with some previous studies conducted in California where the authors looked at racial differences in the SMM outcome and they reported at least a one-and-a-half-fold increased adjusted relative risk of non-transfusion SMM across all racial and ethnic groups. So again, our study focused mainly on iron deficiency anemia, but they are in line with other studies, given that iron deficiency anemia causes the majority of the nutritional anemia.
Patrick Sullivan:So, given that, what do you think the implications are of your findings for iron deficiency anemia? Sort of practice or policy?
Nansi Boghossian:So our findings highlight the need for improved education and counseling about the benefits of iron supplementation and the risks of iron deficiency anemia. This can lead to better patient understanding and adherence of the importance of this. For individuals who experience significant side effects from oral iron, such as constipation or vomiting, policies could support the use of intravenous or IV iron as a potential viable alternative. This would ensure that all patients have access to effective treatment options. Implementing policies that would mandate regular follow-ups as well and monitoring of iron levels can help identify non-compliance early and address it promptly. In regard to advancing racial and ethnic equity, again there should be an attempt to address disparities in access. Basically, ensuring equitable access to iron supplementation and alternatives such as IV iron can reduce these disparities in maternal health outcomes, and also training healthcare providers in culturally competent care can improve communication and trust with the patients from diverse backgrounds, leading, hopefully, to better adherence to supplementation guidelines.
Patrick Sullivan:So you got at this a little bit in your answer, which I appreciate, which is you know, how do we deal with the fact that there are medical approaches, you know, to preventing this iron deficiency anemia and the associated severe maternal mortality, but the compliance with them seems low for those iron supplements. So are there any specific recommendations about how to deal with just the low compliance with these recommendations?
Nansi Boghossian:So I would say the first step would be education and counseling, providing comprehensive education about the benefits of iron supplementation and the risk of iron deficiency anemia. Not all care providers and patients understand how iron supports both the mom and the fetus, so more information and more education on that is important. But what's also important is to try to manage side effects. So pills can result in symptoms such as nausea and constipation, and addressing these side effects can improve adherence. This might involve recommending taking iron supplements with food, or using a different formulation or splitting the dose. Potentially, maybe implementing reminders in the healthcare system once the patient goes to see the care provider, or sending text messages to the mom can help individuals remember to take their supplements. And then regular follow-ups, regular check-ins with the healthcare providers in order to monitor the iron levels and discuss any potential issues with supplementation. That can also be a way in order to improve adherence.
Patrick Sullivan:Thank you. So we're going to move now to some questions that are less about the clinical conditions and more about what it's like to be a researcher doing this kind of research and how the research comes about. We call this behind the paper and it's just a chance to talk a little more about your process. You know our listeners are a combination of epidemiologists who might not work in your field. We have earlier career colleagues who might be in graduate school or doctoral programs or early career faculty. So just want to ask you a few questions about how you come up with and execute this kind of research. So maybe if you could first just tell us how this particular research question came up for you, how did you land on this as a good idea or an important question to ask?
Nansi Boghossian:Yes. So I'm interested in sickle cell disease, and when we started looking at that as an exposure in relation to severe maternal morbidity and started to code the ICD codes, we realized that we have a very high rate of iron deficiency anemia. And so that was a first look sort of at this important question. And then, looking back at the literature, we realized there aren't a whole lot of studies looking at this important issue, and so that was the reason why we looked at that. So it stemmed first from interest in sickle cell disease anemia in order to and then subsequently looking at iron deficiency anemia.
Patrick Sullivan:Thank you. What do you think is the most challenging and maybe also the most rewarding part about being a researcher working in this particular area?
Nansi Boghossian:I think there's more rewarding parts compared to the challenging parts. The main challenging part, I would say, is navigating the unknown, especially when it comes to applying for grant funding. I'm not sure the grant will make it, so I would think that this is the most challenging piece. The more rewarding parts are, just you know, the thrill of discovering something new and contributing to scientific advancements and knowing that, hopefully, knowing that your research would result in an impact in the society and in people's lives, and that's very highly rewarding and in people's lives and that's very highly rewarding.
Patrick Sullivan:Yeah, and I think some people, sometimes people who don't do this kind of work, may not appreciate what that life cycle is. From like thinking about a grant, writing a grant, getting the money, getting the data, doing the analysis. It really can be quite a long time frame. Can you estimate how long this project ran from like the idea to getting some support for it, to the getting the data, the analysis and getting it published? What's that lifecycle of a project like for you?
Nansi Boghossian:Yeah, so this is part of my R01. And currently I'm in the fifth year of the R01. So it was one of the earlier projects that we started and it's a long process. Long process in terms of getting the data, approaching the states to get that data and going back and forth about the data use agreements and then, after getting the data, harmonizing the data between the states. Different states code things differently. Things might be coded in different places in the birth certificates and in the hospital discharge records, so deciding on which source to use for the data is also critical, given that we know that birth certificates under code a lot of outcomes, especially related to pregnancy complications. And then doing the analysis, and so I agree it is a long journey from the time you get the grant until you execute the analysis and publish the paper.
Patrick Sullivan:Well, congratulations on the R01 grant and thanks for sharing a little bit of what has to happen, even before you get to the beginning of your methods section, probably in terms of accumulating those data, I'd like to just end with one more question.
Patrick Sullivan:I know at Emory University where I teach and I'm sure where you do your work and teach that there's a lot of interest in child and maternal health among our students, child and maternal health among our students. So do you have any advice for public health students or other students who are interested in child and maternal health in terms of pursuing a career in research in this field?
Nansi Boghossian:Yes, I think it's really important to get involved in research projects early on. This helps in developing these research skills, but it also helps in networking and collaborating and knowing how teams function. All of these are critical, important networks for also -future- securing a postdoc, for example, or securing your first position after you finish your postdoc. Keep yourself updated with the latest literature and latest research by reading journals. But then the most important thing I would say is to be passionate about what you're doing and be persistent. I think to wake up and do what we're doing, you have to be really passionate, and that's when a job doesn't feel like a job anymore. It feels like something you enjoy doing on a daily basis. And so, being passionate about what you do and persistent, that will result in important outcomes for your research and future career trajectory.
Patrick Sullivan:Well, that really feels like ending on a high point and thank you for that really positive reflection about doing the work. And our listeners can't see we're on Zoom and can see each other but just the visible joy when you talk about doing this work and it's clear from your voice and from how we are seeing each other that this is an area of passion for you. So congratulations on finding that meaningful thing and really important thread of research. So I want to just give you a chance to share with us any last thoughts you'd like to share with our listeners about your research, about the process or about actions that they could take to improve public health in this area. Any last thoughts?
Nansi Boghossian:Yeah, thank you again. Thank you for all the questions and I very much enjoyed this. Last thoughts- I think there's still a lot to be done in this area. The research that we did did not look at the severity of iron deficiency anemia. I know there's a couple of studies, couple of trials, trying to look at how IV iron supplementation can improve maternal outcomes, but I believe this is an important topic for future research and I'm looking forward to seeing what can come out of more research being done in this area and how that can advance racial equity in terms of severe and adverse outcomes to moms and babies.
Patrick Sullivan:That brings us to the end of this episode. Thank you so much again, Dr. Boghossian, for joining us today. It was such a pleasure to have you on the podcast.
Nansi Boghossian:Thank you, thanks again for having me.
Patrick Sullivan:I'm your host, Patrick Sullivan. Thanks for tuning in to this episode and see you next time on EPITalk, brought to you by Annals of Epidemiology, the official journal of the American College of Epidemiology. For a transcript of this podcast, or to read the article featured on this episode and more from the journal, you can visit us online at www. annalsofepidemiology. org.
