January 17, 1997

Study shows most low-weight infants escape multiple handicaps

Study shows most low-weight infants escape multiple handicaps

The majority of extremely low-birthweight infants born at Vanderbilt University Medical Center and cared for in the Neonatal Intensive Care nursery grow up without multiple handicaps.

In a follow-up study conducted at VUMC, researchers instead found that only a relatively small percentage of these at-risk infants ‹ 12 to 13 percent ‹ grow up with multiple handicaps.

"People have long been concerned that very low birthweight babies will have multiple handicaps," said Susan C. DonLevy, R.N., M.S.N., Associate in Pediatrics and coordinator of the follow-up program. "By far the majority of survivors are not multiply handicapped and are not mentally retarded."

The study involved 535 infants weighing less than 1,000 grams (1 pound, 3 ounces) born at VUMC between 1982 and 1989. Most of the infants were seen for follow-up visits in the clinic, long maintained by the Neonatology division. Of the 535 infants, 57 percent survived. Data are available for more than 80 percent of those enrolled in the followup program.

According to DonLevy, who operates under the medical direction of Dr. Robert B. Cotton, professor of Pediatrics, the infants were divided into two groups ‹ those born between 1982 and 1985 and those between 1985 and 1989. Statistics showed that survival of the infants increased from 40 to 48 percent between 1982 and 1985 to 60 percent between 1985 and 1989.

"Now we're seeing survival rates at 80 and 90 percent since the introduction of surfactant, the wonder drug of neonatology," DonLevy said. Surfactant is a drug with the ability to treat respiratory complications in premature infants, therefore decreasing ventilator time and hospital stays and increasing survival rates.

"The survival rate of these infants has nearly doubled from 1982 until now. It used to be that survival of a premature infant was very extraordinary and occassional. Now we have large enough groups of survivors to be studied," DonLevy said.

DonLevy said that the long-term followups are important to evaluate techniques in neonatology. In these days of health care form, a great deal is at stake financially. Thirty five percent of the national child health care dollar is spent on infants weighing less than 2,500 grams, and 19 percent is spent on children under 1,000 grams.

The long term goal of the VUMC followup project was simple; to find out about the lives of the surviving children. DonLevy said the results of the study are similar to two other major studies done recently in Cleveland and Seattle.

Of the infants studied, 12 to 13 percent had multiple disabilities, including blindness, visual impairment, hearing loss, mental retardation and cerebral palsy.

DonLevy said the largest number ‹ 72 percent ‹ have had academic difficulties resulting from trouble processing information, and have required special school resources.

DonLevy, who began her career in neonatology as a nurse caring for some of these infants, said that the families of these children are very proud of the accomplishments of their children.

"They are very grateful to Vanderbilt for taking care of their child," she said.

VUMC's neonatal followup program includes checkups of premature infants six, 12 and 18 months, three years and seven years.

The checkups include an audiologic evaluation in the Vanderbilt Audiology Department, speech assessment by a speech and language pathologist from the Bill Wilkerson Center and I.Q. and school skills testing by a psychologist from the Vanderbilt Child Development Center.

"But our resources are limited and we've had to look at a way to get this information in other ways," DonLevy said. As a result, since the population of Middle Tennessee is fairly constant, many former patients who did not come to Vanderbilt for followup care were found and their families were interviewed on the phone for the follow-up study.

VUMC has been involved in the follow-up of premature infants since the early 1960s. Dr. Mildred T. Stahlman, professor of Pediatrics, has been commited to following children who were born prematurely since her early work with research and treatment of children with Hyaline Membrane Disease.

DonLevy said that studying the outcome of very low birthweight babies seems like an easy task ‹ just track them down and find out how they're doing ‹ but it's not.

"It's difficult to do. Patients and their families move around, making it hard to find out any followup information," DonLevy said.

DonLevy said talking with the families has been rewarding.

"I feel that these children and families are a very special group. All parents believe their children are miracles, but these children have overcome incredible odds and it's truly been a privilege to work with them all of these years.

"There's so much we don't know about these kids. Their increased survival poses new questions for medical practice, research and society."