MEDICATIONS: NEWBORN SCREENING FOR CERTAIN GENETIC DISORDERS HAS BENEFITS AND SOME DRAWBACKS

November 18, 2003 — Expanded newborn screening for biochemical genetic disorders may lead to improved health outcomes for affected children and lower stress for their parents, however, false-positive screening results may place families at risk of increased stress, according to a study in the November 19 issue of The Journal of the American Medical Association.

According to background information in the article, routine newborn screening is required practice for newborn care throughout the United States. Traditionally, testing for various disorders required a separate test, but now with a measuring device called the tandem mass spectrometry, biochemical genetic screening of up to 20 disorders can be performed from only one blood sample from the newborn. To date 24 states have started this expanded newborn screening using tandem mass spectrometry. Four states have not yet implemented mandated programs and four states offer non-mandated expanded screening.

In this study, Susan E. Waisbren, Ph.D., from Children's Hospital, Boston, and colleagues compared newborn identification by expanded screening with clinical identification of biochemical genetic disorders. The researchers also assessed the impact on families of a false-positive screening result compared with a normal result. False-positive results are defined by the researchers as initial out-of-range screening results that do not signify a metabolic disorder on further evaluation of the child.

The sample included families of 50 affected children identified through expanded newborn screening and 33 affected children identified clinically. In addition, families of 94 children found to have false-positive newborn screening results and 81 children having normal newborn screening results were also enrolled. A total of 254 mothers and 153 fathers were interviewed.

"Within the first six months of life, 28 percent of children identified by newborn screening compared with 55 percent of clinically identified children required hospitalization," the researchers report. "One child identified by newborn screening compared with eight (42 percent) identified clinically performed in the range of mental retardation. Mothers in the screened group reported lower overall stress on the Parental Stress Index than mothers in the clinically identified group." The researchers also found that children with false-positive results compared with children with normal results were twice as likely to be hospitalized (21 percent vs. 10 percent). And mothers of children in the false-positive group compared with mothers of children with normal screening results had higher scores on the Parental Stress Index and the Parent-Child Dysfunction subscale.

In conclusion the authors write: "... this study highlights some of the challenges to current newborn screening practices. It demonstrates a need for education about newborn screening for parents prior to the birth of their child. Education about these rare and complex metabolic disorders also is needed for primary care physicians and other health care professionals, especially since face-to-face discussions with these professionals appear to reduce parental stress. Genetic counselors, rarely consulted, also may provide valuable reproductive counseling and information. Basic concepts such as carrier status and the meaning of a false-positive finding would be helpful for parents of all children who have a positive screening result."