Public Health Service study of Reye's syndrome and medications. Report of the main study.

Between January 1985 and May 1986, following completion of a pilot study, a main study concerning the possible association between Reye's syndrome and salicylates was conducted. Twenty-seven patients with stage II or deeper Reye's syndrome whose diagnoses were confirmed by an expert panel and who had appropriate antecedent illnesses (chickenpox, respiratory illness, or gastrointestinal illness) prior to the onset of Reye's syndrome were compared with 140 controls matched for age, race (black or not black), and type and timing of onset of antecedent illness. Controls were selected from the same hospital, emergency room, or school as case-patients or were identified by random-digit telephone dialing. As in the pilot study, a strong statistical association with ingestion of salicylates during the antecedent illness and prior to the onset of Reye's syndrome was observed (odds ratio, 40; lower 95% confidence limit, 5.8). Analysis of the independent risk of aspirin and nonaspirin salicylates revealed a significant association with aspirin (odds ratio, 26; lower 95% confidence limit, 6.4); the independent risk of nonaspirin salicylates could not be assessed because only two cases were not exposed to aspirin. Assessment of epidemiologic issues of concern, including case-control differences in the severity of the antecedent illness, did not explain the high odds ratios that were observed. The high percentage of patients with Reye's syndrome exposed to salicylates (greater than or equal to 90%) in this and prior studies suggests that, though the reported incidence of Reye's syndrome has declined in recent years, concomitant with a decline in salicylate use among children, a majority of Reye's syndrome cases may be attributable to salicylate use.

Public Health Service study on Reye's syndrome and medications. Report of the pilot phase.

Between February and May 1984, we conducted a pilot study to examine the methods for a larger study of a previously reported relation between Reye's syndrome and medications. Thirty patients with Reye's syndrome, whose diagnosis was confirmed by an expert panel, and 145 controls were matched for age, race (black or not black), and antecedent illness (respiratory infection, chickenpox, or diarrhea) and selected from the same hospital, emergency room, or school, or identified by random digit dialing. Significantly more cases (93 per cent, 28 of 30) than members of each of the four control groups or all controls combined (46 per cent, 66 of 145) had received salicylates during matched antecedent illnesses (odds ratio of all 30 cases vs. all controls = 16.1; lower 95 per cent confidence limit = 4.6). The prevalence and mean severity score of signs, symptoms, and selected events during the antecedent illness tended to be lower among cases than controls. Thus, differences in the severity of this illness between cases and controls did not explain differences in medication exposures. This pilot study suggests an association between Reye's syndrome and the use of salicylates during an antecedent illness.

Perinatal bacterial infection after prolonged rupture of amniotic membranes: an analysis of risk and management.

Chi-square and logistic stepwise multiple regression analysis of perinatal determinants of infant bacterial infection following prolonged rupture of amniotic membranes for 24 hours or more prior to delivery was applied in 33 infected infants and 66 matched control infants from the NINCDS Collaborative Project. In order of statistical significance, the most important variables were placental inflammation (P = 0.002), gestational age less than 34 weeks (P = 0.008), gestational age 34 to 37 weeks (P = 0.013), male sex (P = 0.015), Apgar score less than 6 at 5 minutes (P = 0.023), and clinical amnionitis (maternal fever, fetal tachycardia, or amniotic or gastric fluid leukocytes or bacteria) (P = 0.044). Duration of labor during PROM, race, and maternal age and parity were insignificant. Using these predictive variables, identification of infected infants for either microbial surveillance (superficial and systemic cultures) or microbial surveillance and anticipatory antibiotic therapy (discontinued after 3 days of negative cultures) was highly significant (P = 0.0001). Incorporating these variables and derived coefficients from multivariate analysis, a mathematical model was used for evaluation and prediction of perinatal bacterial infection with a sensitivity of 82% and specificity of 70%. Analysis of 46 infants prior to and 310 infants after implementation of this process at Harbor-UCLA Medical Center indicated significant improvement in the appropriate management of these infants at risk (from 59% to 87% of the population, P less than 0.05). Inappropriate antibiotic therapy decreased from 35% to 10% (P less than 0.05). In the absence of a shift in the median days of hospitalization of non-PROM infants, determination of the grand median days of PROM infant hospital stay showed a decrease (P less than 0.01) after initiation of this evaluation and management scheme.

Toxicity to bilirubin in neonates: infant development during first year in relation to maximum neonatal serum bilirubin concentration.

Neurologic and developmental performance during the first year of life was correlated with maximum neonatal serum bilirubin levels for 27,000 infants in the Collaborative Perinatal Project. The infants were grouped by race and by five birth weight/gestational age categories to control for the effect of these factors on hyperbilirubinemia and developmental outcome. Low mean eight-month motor scores and delayed one-year motor development were associated with serum bilirubin levels in the range of 10 to 14 mg/dl and above. This relationship was strongest for low-birth-weight/short-gestational-period infants. A persistent association of developmental outcome with hyperbilirubinemia was found over and above the variation of maturity within the birth weight/gestational age categories.

Sudden infant death syndrome. A prospective study.

One hundred twenty-five sudden infant death syndrome (SIDS) victims followed up since birth from a large prospective study were compared with matched controls. Some of the future SIDS victims showed evidences of neonatal brain dysfunction including abnormalities in respiration, feeding, temperature regulation, and specific neurologic tests. These abnormalities could not be ralated to events in labor or delivery. A greater proportion of the future victims were mildly underweight for gestational age. The gestations that produced the SIDS victims were characterized by a greater frequency of mothers who smoked cigarettes and had anemia. The demographic profile of SIDS families proved to be indentical to the profile for families with excessive perinatal mortality. Many of the SIDS victims showed a retardation in postnatal growth prior to death.

The effect of intrauterine hypoxia on the child surviving to 4 years.

Intrauterine hypoxia/asphyxia is an unchallenged cause of perinatal death, but whether sublethal degrees of hypoxia result frequently in brain damage in surviving infants is less certain. To test this hypothesis, obstetric patients with abruptio placentae, placenta previa, and prolapse of the umbilical cord were computer matched on several factors with normal control patients to determine the degree of risk of lower 4 year Stanford-Binet I. Q. scores or abnormalities on the 4 year fine motor and gross motor testings. The mean I. Q. score of babies born of mothers with one of these complications was no different from that of the normal controls. Similarly negative results were recorded on the 4 year fine motor and gross motor testings. Children of low birth weight in either group experienced lower I. Q. scores and higher risk of abnormal findings on the motor tests at 4 years than the babies of mature birth weight. Intrauterine hypoxia/asphyxia apparently is not a major cause of neurologic dysfunction in the surviving child.