Ninth Annual Maternal and Child Health Epidemiology Conference / December 10-12, 2003

Composite “Pictures” of Infant Mortality in MS: 2003

MARIANNE ZOTTI:  Okay.  In this presentation, we’re going to be describing how we use perinatal periods of risk to create a composite picture of infant mortality in Mississippi.  And for those of you who haven’t done perinatal periods of risk, I just wanted to include a little bit of background.  And it goes to the idea that infant mortality does not just have one cause.  Obviously, if it did, we would have solved that a long time ago.  The perinatal periods of risk is an approach to examine fetal and infant mortality that enables us to look at each component that contributes to the overall rate by using birth weight and age at death.  And all fetal and infant deaths are divided into two categories:  the very low birth weight there, and those that are above very low birth weight.  And then, they’re also divided into those that occur in the fetal and neonatal and post neonatal periods.  And then, other limitations have to do with infant deaths were excluded if birth weight was less than 500 grams, and fetal deaths must be 24 weeks or more of gestational age and 500 grams. 

Here, we see the contributing causes for each component, and that’s the reason why we do a perinatal periods of risk.  In maternal health, prematurity--often the preconceptional health of the mother is the important contributor.  Her health behaviors can influence whether the infant lives or dies.  And in addition, perinatal care is very important for the very low birth weight infant.  Literature has shown that very low birth weight infants need to be born in a hospital with the highest level of perinatal services to enhance their ability to survive.  In maternal care, the focus is on prenatal care, identification of risk, and referral of women who have complicated pregnancies.  The component of newborn care relates to neonatal intensive care unit for infants that weigh 1500 grams or more.  And then, the infant health--this final one on the bottom--relates to post neonatal causes of death such as Sudden Infant Death Syndrome, or SIDS.  So the focus is on risk reduction. 

In this slide, we begin to examine the fetal infant deaths among Mississippi residents from 1997 to ’99.  And the total rate is at the bottom.  It’s 13.8.  And each component reveals its contribution to the overall rate.  And if you add the numbers in each of these components, they add up to what the total is here.  So what you can see is that the largest contributor is maternal health prematurity, and then the second ones are maternal care and infant health.  Now, to determine the relative contributions for each component, we compute an overall rate and rates for each of those components for a reference group.  And the reference group is selected because they have the lowest mortality in the population.  And the assumption is that if there’s one group that can achieve this, then any group should be able to achieve this.  And the reference group is composed of White, non-Hispanic, 20 or more years of age, and more than 12 years of education.  And I don’t have a slide to show that. 

We’ve skipped with the next slide, then, because what we used with the reference group--we used that data, and we subtract the reference group rates from each of the components in the overall, and that gives us the excess mortality that we’re experiencing.  And so when you look here, again you see the same pattern as I described before.  And you can see here that this one is not highlighted because it’s a very small contribution that newborn care makes in the excess.  And so that doesn’t mean we need to stop anything that we’re doing in terms of newborn care; but we probably don’t need additional strategies.  Then, we used the same procedure for looking at fetal infant mortality by race.  And so this shows the total for Whites, and again, you can see the same kind of a pattern.  And then, we used the same reference group, subtracted, and it gave us this 2.1.  And most of these are very small contributions.  And what this really demonstrated is that we really need to focus more on Blacks.  And Mississippi is unique in that nearly half of the births in Mississippi are to Black women. 

This is the PPOR results for Blacks, and you can see that the total is very large.  And again, you can see the same pattern as we saw in the others.  And now, here are the excess.  We used the same reference group, and we subtracted.  And you can see here we have a total of 11.0, and that total excess--and that’s the excess--is larger than the White overall.  And again, newborn care for these infants right here does not make a significant contribution.  So the summary of this section is that regardless of race, the component that contributes most to fetal infant mortality rate is the maternal health and prematurity.  Maternal care and infant health contribute almost equally, and while there’s very little contribution in the newborn care.  And lastly, Blacks exhibit excess mortality when compared with the reference group whereas the Whites don’t.  So the next section, we’re really going to be shifting gears now and say, “How did we use this on the statewide level?”  We reviewed studies and programs and policies that pertained to each of the components of the excess mortality.  Then, we had a group discussion of the MCH team, which consists of various program directors, to focus our Title V Maternal and Child Health *Block Grant plan that we related to infant mortality.  So this just shows that we started with maternal health prematurity, and the number that’s on that is the overall.  And then, these pieces over here talk about the topics that we would be discussing. 

So we started with perinatal regionalization, because remember, this component consists entirely of the very low birth weight.  So we had done a study from 1997 to ’99 using birth and infant death files in which we examined regionalization effects on mortality.  And we classified the hospitals by levels of perinatal services.  Level “A” is the highest.  This is our results.  This slide reveals that only 40 percent of the infants were born in a level “A” hospital, and that’s the lowest statewide proportion in the United States.  Then, we examined the effects of the level of hospital on mortality.  When we controlled for the less than 1000-gram infants, decreasing the level of hospital significantly increased mortality with the exception of two large level B hospitals, and they performed as well as our “A” hospitals.  However, when we examined the effects of the level of hospital on infants less than 1000 grams, each level of hospital that was not an “A” significantly increased infant mortality.  The results of this study have led our Perinatal Association to make Perinatal Regionalization System its priority for this next year, and the health department is going to be working with that association as it develops strategies to address the perinatal system.  Now, of course, there were other things in this category as well, some other maternal behaviors.  So folic acid was one, and we had a cross-sectional study that had been conducted statewide out of community health clinics and health department family planning clinics to assess knowledge and behavior regarding folic acid.  So data from 3,107 childbearing women who were receiving initial family planning services were collected in one month. 

This slide shows that knowledge about folic acid is lacking and that most of these women do not use a multivitamin.  An obstetrician/gynecologist at the health department chairs the statewide Folic Acid Council, so he’s going to be continuing his education strategies.  And also, the health department since the time that we had our discussion published a report of this study in its provider bulletin to highlight the importance of provider interventions that promote the use of folic acid.  Smoking is another behavior that’s important.  We had conducted a study about prenatal smoking from using data from 1995 to ’97, and it was linked to birth and death files.  And of course, you can see that prenatal smoking was decreasing, but it was increasing among teenage women.  And based on that study, the health department had already created a Title V state performance measure to monitor the proportion of prenatal smoking among teenage women.  And the good and the bad news is that it stabilized, and so we had a lot of discussion about current and proposed activities of the health department and the Partnership for a Healthy Mississippi, who is very powerful in Mississippi, to address smoking in this age group.  There were other things that we’d be interested in having information, but we don’t have information at this point.  But we just completed our first year of PRAMS, and so that as we do this kind of a discussion during this next year, we’ll be able to bring in our information from PRAMS related to these things.  Interpregnancy interval is another thing that’s important and that can affect mortality, and 18 to 24 months is the ideal interval between pregnancies. 

This slide reveals that among women giving birth--now, this is again focused on the very low birth weight--about a third had an interpregnancy interval less than 18 months.  The highest risk, of course, is among those zero to three months.  These are the demographic characteristics of the women who had preterm births, and they reveal a lot about how the health department needs to tailor its messages for risk reduction for preterm birth.  Now, we’re moving to the maternal care component.  And again, on the right, to your right, tells the things that we’re interested in.  So we looked at prenatal care utilization, and here we can see there’s a racial disparity in the adequate category of prenatal care.  And that can be related to a variety of factors such as inability to find a prenatal provider and transportation barriers.  And Mississippi continues to struggle as more and more physicians are quitting prenatal care and delivery.  So the health department may need to expand its maternity services to enable women to obtain prenatal care without traveling hours to get it.  We again looked at interpregnancy interval and you can see that these results are very similar to those in the very low birth weight category. 

Now, we’re skipping to infant health.  And remember, the reason why we didn’t address newborn care is because there’s not excess mortality in that component.  The SIDS coalition and the health department contracted with a research group in 2000 to conduct a telephone survey among 501 households with phones and children who were then less than two years old, and the major results are on this slide.  It was encouraging to see that more than half of the women stopped smoking while they were pregnant.  However, because women often resume smoking after birth, especially when the partner smokes, interventions to reduce maternal smoking need to address family and not just the woman.  And there’s a lot of smoking, a lot of emphasis in Mississippi.  And of course, if you remember, the very first tobacco initiatives began in Mississippi, and so there’s--we have a fair amount that goes on both through the partnership and through the health department.  These results also demonstrate the need for a consistent “Back to Sleep” message.  And then, it also revealed the importance of health messages from the provider and the hospital staff. 

Breastfeeding is another thing that we’re interested in, and the *Ross Mothers’ survey is carried out by WIC every year.  And these results show that we have had an increase in breastfeeding from 1995 to 2000, both immediately after birth and at six months.  It’s not on here, but we also--it’s much smaller, but we also had an increase, the same kind of pattern that we saw among the WIC women.  And our WIC breastfeeding program is very strong in Mississippi, and in fact, they do consulting with other states.  And so they’re going to be continuing to put emphasis on the importance of breastfeeding.  Now, this is really the bottom line of the story here.  We’ve talked a lot about numbers and factors that contribute to fetal and infant mortality and how we can address those factors through public health strategies; but now, these pictures show us that the numbers and the factors really aren’t what this is about.  The bottom line is about the lives of babies and the families that they affect.  Remembering them helps us to use our analytic and intervention strategies to keep these precious babies healthy and alive for his or her first birthday.  Thank you.