BOSTON - A cascade of untoward events can ensue from a false-positive result on newborn screening for genetic disorders, particularly if the parents are not properly briefed by a clinician.
BOSTON, June 5 ? A cascade of untoward events can ensue from a false-positive result on newborn screening for genetic disorders, particularly if the parents are not properly briefed by a clinician.
The stress and shock of the potentially devastating news about metabolic disorders is not necessarily ameliorated even after retesting finds that the initial positive result was false, found a team at Children's Hospital Boston.
That stress can negatively affect the parent-child relationship, the parents' perceptions about their own health, and their outlook for their children and family, the investigators reported in the June issue of Pediatrics.
"False-positive results may lead to increased parental stress," wrote Elizabeth A. Gurian, B.S., and colleagues "This is especially true for parents who have not received adequate information about newborn screening."
Keeping parents better informed about the need and the reasons for repeat screening might help to relieve at least some of the stress engendered by a positive screening result, the authors suggested.
"The timing of parental education about expanded screening and the speed with which a metabolic disorder can be ruled out also may be important," they wrote. "Specific communication plans for informing parents, fact sheets, and better distribution of newborn screening information materials during the prenatal and postnatal periods might be initiatives to consider to alleviate parental stress regarding false-positive results."
Every year in the United States about four million newborn infants are screened for metabolic disorders with tandem mass spectrometry. Severe disorders are detected in about 3,000 and about 13,000 of the screened children, or one in 2,400, will have a false-positive result.
"Generally these results are not laboratory mistakes but rather are transient findings or indications of variant or carrier status," the authors wrote.
But for most parents, it's not the logistics of testing that matters but the possibility that their child may have a devastating disease, or that they may have inadvertently passed a harmful genetic trait on to their offspring.
To get an idea of how parents respond to the news of a positive (or false-positive) test, the authors surveyed parents whose children were enrolled in Massachusetts' expanded newborn screening program, which tests for more than 20 metabolic disorders.
Both mothers and fathers of kids who had a false-positive result on one of the tests were invited to participate when their child was first referred for additional confirmatory testing, and were surveyed six or more months after the test was determined to have been falsely positive.
Parents of children who died or whose children were born weighing less than 2,500 grams were excluded.
A second group of parents whose children had received normal results were used for comparison.
Parents took part in a structured interview consisting of questions relating to their children's health and their own, an understanding of the newborn-screening process, and background information. Parents in the comparison group completed the same interview.
The parents of infants with false-positives were also asked about the repeat screen, and they and the comparison group parents were then asked to complete a parenting stress index short form. The instruments consist of a 36-item questionnaire that provides a total stress score, plus subscale scores, looking at parental distress, parent-child dysfunctional interaction, and difficult child. Mothers and fathers completed the stress index separately.
The investigators surveyed parents of 173 children with false-positive results and of 67 children with normal results. A total of 233 mothers 123 fathers were interviewed.
The authors found that "although parents in the two groups reported similar degrees of worry about their child's health, mothers in the false-positive group reported more worry about their child's future (mean: 2.4; SD: 1.4), compared with mothers in the normal-screened group (mean: 1.9; SD: 1.0; P=0.04)."
Mothers whose children tested-false positive said they themselves were less healthy than mothers whose babies had normal results, and 15% of mothers in the false-positive group said that their child required extra parental care, compared with only 3% of mothers in the comparison group (P=0.01).
Perhaps reflecting a social reality, "fathers in the false-positive group did not differ from fathers in the normal-screened group in reporting worry about their child's future, personal health, and their child's extra care requirements," the authors found.
Responding to the parenting stress index questionnaire, mothers in the false-positive group reported higher overall stress on than did moms in the comparison group. In all, 17 (11%) of mothers in false positive had index scores higher than 85, suggesting a need for clinical intervention. In contrast, none of the mothers in the normal-screening group had scores in that range (P=0.008).
"The differences between groups were more pronounced on the total score, difficult child, and parent-child dysfunctional interaction subscales (P
Although the fathers appeared to be more phlegmatic than the mothers regarding their children's future, they too felt the stress of a false-positive result, with higher overall stress on the parenting stress index compared with fathers in the normal-screened group, particularly on the total score (P=0.02), difficult child (P=0.05), and parent-child dysfunctional interaction subscales (P=0.004).
When the investigators adjusted for marital and socioeconomic status, they found that the results were similar between the two groups. They also found that when parents knew the reason for the repeat screen, they tended to be less stressed-out than parents who were left in the dark about why a second screen was required. Only about one-third of parents knew the real reason why a test was repeated.
When asked what could be done to make the screening process "a more positive experience" for them, 61% of parents in the false-positive group said they needed more information about newborn screening and the test result, 13% reported being ambivalent about newborn screening, and 26% said they were concerned about how long it took to get confirmation
The investigators noted that "50% of parents surveyed indicated that they were never told or did not recall being told the result of the repeat screen. It is possible that some of these parents were told but did not recall receiving the information. Twenty-two percent of these parents reported being told to expect 'no news is good news,' and 24% needed to ask their pediatrician specifically for the results of the repeat screen."