RESUMEN

OBJECTIVE: To test the hypothesis that levels of the endogenous inhibitor of nitric oxide production, asymmetric dimethylarginine (ADMA), would be greater in preterm infants with bronchopulmonary dysplasia (BPD)-associated pulmonary hypertension (PH) than in infants with BPD alone. STUDY DESIGN: A case-control study of 23 patients with both BPD and PH (cases) and 95 patients with BPD but no evidence of PH (controls). Levels of ADMA were compared between cases and controls by t test. RESULTS: Patients with both BPD and PH had greater plasma levels of ADMA than patients with BPD alone (P = .04). In samples drawn before 28 days of life, greater levels of ADMA were again found in cases compared with controls (P = .02). The plasma arginine-to-ADMA ratio was lower in cases than in controls (P = .03), suggesting a greater likelihood of inhibition of nitric oxide production in patients with both BPD and PH than in patients with BPD alone. CONCLUSION: In this neonatal BPD cohort, ADMA levels are increased in patients with BPD who develop PH. We speculate that ADMA may be both a biomarker and a potential therapeutic target for preterm infants with BPD-associated PH.

Asunto(s)

RESUMEN

BACKGROUND: Animal studies have linked in utero vitamin D exposure to various aspects of offspring brain development. Limited research has translated these findings to humans, and none have employed cord blood to measure exposure late in gestation. METHODS: Our objective was to examine the associations between maternal 25(OH)D measured at ≤26 weeks' gestation or cord blood 25(OH)D and offspring global development, IQ, achievement, and behaviour in the US Collaborative Perinatal Project (1959-73). This was a secondary analysis of data from a case-cohort study, with 3896 women and children who participated in at least one outcome assessment. Psychologists assessed global development at 8 months, IQ and behaviour at 4 and 7 years, and achievement at 7 years. Multiple linear and logistic regression was used to examine the associations between 25(OH)D and child outcomes, controlling for maternal education, age, parity, race, maternal body mass index, marital status, smoking, gestational age and month of blood draw, and study site. RESULTS: Positive associations for many outcomes were greatly attenuated upon adjustment for confounders and were generally null. Only IQ at age 7 was associated with both maternal and cord blood 25(OH)D, but the effect estimates were very small (ß for 5 nmol/L increment of maternal 25(OH)D = 0.10; [95% CI 0.00, 0.19]). CONCLUSION: We observed very little indication that maternal or cord blood 25(OH)D are associated with cognitive development, achievement, and behaviour between 8 months and 7 years of age.

Asunto(s)

RESUMEN

OBJECTIVE: 17-alpha hydroxyprogesterone caproate 250 mg weekly reduces recurrent spontaneous preterm birth in women with a prior spontaneous preterm birth by 33%. The dose is not based on pharmacologic considerations. A therapeutic concentration has not been determined hampering any attempt to optimize treatment. This study evaluated the relationship between 17-alpha hydroxyprogesterone caproate plasma concentrations and the rate of spontaneous preterm birth in women with singleton gestation. STUDY DESIGN: A single blood sample was obtained between 25 and 28 weeks' gestation from 315 women with a spontaneous preterm birth who participated in a placebo-controlled, prospective, randomized clinical trial evaluating the benefit of omega-3 supplementation in reducing preterm birth. All women in the parent study received 17-alpha hydroxyprogesterone caproate and 434 received omega-3 supplementation and 418 received a placebo. Plasma from 315 consenting women was analyzed for 17-alpha hydroxyprogesterone caproate concentration. RESULTS: There were no differences between placebo and omega-3 supplemented groups in demographic variables, outcomes or in mean 17-alpha hydroxyprogesterone caproate concentration. Plasma concentrations of 17-alpha hydroxyprogesterone caproate ranged from 3.7-56 ng/mL. Women with plasma concentrations of 17-alpha hydroxyprogesterone caproate in the lowest quartile had a significantly higher risk of spontaneous preterm birth (P = .03) and delivered at significantly earlier gestational ages (P = .002) than did women in the second to fourth quartiles. The lowest preterm birth rates were seen when median 17-alpha hydroxyprogesterone caproate concentrations exceeded 6.4 ng/mL. CONCLUSION: Low plasma 17-alpha hydroxyprogesterone caproate concentration is associated with an increased risk of spontaneous preterm birth. This finding validates efficacy of this treatment but suggests that additional studies are needed to determine the optimal dosage.

Asunto(s)

RESUMEN

The relationship between Chlamydia trachomatis (CT) and preeclampsia was examined longitudinally among 205 cases and 423 normotensive controls nested within the Collaborative Perinatal Project. Antibodies were analyzed at a first prenatal visit (mean 14.2 weeks) and at delivery. Prenatal infections were identified as IgG/IgM seroconversion or a four-fold rise in IgG antibody titers. Although serological evidence of incident prenatal CT infection was uncommon (n=9, 1.4%) in this general pregnant population, infected women were more likely to develop preeclampsia, after adjustment for maternal age, body mass index, smoking status, race and time between blood draws (ORadj 7.2, 95% CI 1.3 - 39.7).

RESUMEN

OBJECTIVE: To evaluate the relationship between neonatal oxygen supplementation (O2) and childhood cancer in the Collaborative Perinatal Project (CPP). STUDY DESIGN: The CPP consisted of 54,795 children born between 1959 and 1966 and followed to age 8 years. We used Cox proportional hazards modeling to examine the association between history of neonatal O2 and cancer (n = 48). RESULTS: The hazard ratio (HR) for any O2 was 1.77 (95% confidence interval [CI] = 0.94 to 3.35). The HR for continuous duration of O2 was near 1 and not significant. However, the HRs were 0.69 (95% CI = 0.17 to 2.88) and 2.87 (95% CI = 1.46 to 5.66) when comparing 0 to 2 and 3 or more minutes of O2, respectively, to no O2. The latter association was weaker (HR = 2.00; 95% CI = 0.88 to 4.54) and not significant ( P = .10) when analysis was restricted to cancers diagnosed after age 1 year (n = 41). CONCLUSIONS: These findings are consistent with an association between O 2 for 3 minutes or longer and cancer in childhood, and should serve as a basis for further study.

Asunto(s)