Preterm neonatal morbidity and mortality by gestational age: a contemporary cohort

BACKGROUND

Although preterm birth <37 weeks' gestation is the leading cause of neonatal morbidity and mortality in the United States, the majority of data regarding preterm neonatal outcomes come from older studies, and many reports have been limited to only very preterm neonates. Delineation of neonatal outcomes by delivery gestational age is needed to further clarify the continuum of mortality and morbidity frequencies among preterm neonates.

OBJECTIVE

We sought to describe the contemporary frequencies of neonatal death, neonatal morbidities, and neonatal length of stay across the spectrum of preterm gestational ages.

STUDY DESIGN

This was a secondary analysis of an obstetric cohort of 115,502 women and their neonates who were born in 25 hospitals nationwide, 2008 through 2011. All liveborn nonanomalous singleton preterm (23.0-36.9 weeks of gestation) neonates were included in this analysis. The frequency of neonatal death, major neonatal morbidity (intraventricular hemorrhage grade III/IV, seizures, hypoxic-ischemic encephalopathy, necrotizing enterocolitis stage II/III, bronchopulmonary dysplasia, persistent pulmonary hypertension), and minor neonatal morbidity (hypotension requiring treatment, intraventricular hemorrhage grade I/II, necrotizing enterocolitis stage I, respiratory distress syndrome, hyperbilirubinemia requiring treatment) were calculated by delivery gestational age; each neonate was classified once by the worst outcome for which criteria was met.

RESULTS

In all, 8334 deliveries met inclusion criteria. There were 119 (1.4%) neonatal deaths. In all, 657 (7.9%) neonates had major morbidity, 3136 (37.6%) had minor morbidity, and 4422 (53.1%) survived without any of the studied morbidities. Deaths declined rapidly with each advancing week of gestation. This decline in death was accompanied by an increase in major neonatal morbidity, which peaked at 54.8% at 25 weeks of gestation. As frequencies of death and major neonatal morbidity fell, minor neonatal morbidity increased, peaking at 81.7% at 31 weeks of gestation. The frequency of all morbidities fell >32 weeks. After 25 weeks, neonatal length of hospital stay decreased significantly with each additional completed week of pregnancy; among babies delivered from 26-32 weeks of gestation, each additional week in utero reduced the subsequent length of neonatal hospitalization by a minimum of 8 days. The median postmenstrual age at discharge nadired around 36 weeks' postmenstrual age for babies born at 31-35 weeks of gestation.

CONCLUSION

Our data show that there is a continuum of outcomes, with each additional week of gestation conferring survival benefit while reducing the length of initial hospitalization. These contemporary data can be useful for patient counseling regarding preterm outcomes.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Recruitment of infants with sickle cell anemia to a Phase III trial: data from the BABY HUG study

BACKGROUND

Protocol-eligible subjects may not be candidates for research participation or may decline. To determine factors that affected accrual, we evaluated enrollment in BABY HUG, a multi-center, randomized, placebo-controlled Phase III trial of hydroxyurea (HU) in infants with sickle cell anemia.

METHODS

An anonymized registry of potential subjects served as the primary source of data. Study coordinators considered all infants less than age 18 months with a hemoglobin FS diagnosis on newborn screening. Data included the number of potentially eligible subjects, whether parents were approached, and reasons for participating or declining.

RESULTS

Of 1106 potential participants, 28% were not approached for reasons such as prior poor adherence to clinical care. Interested families expressed willingness to contribute to medical knowledge (51%), hope of being randomized to receive hydroxyurea (51%), and desire for closer clinical care (51%) as reasons for participating. Disease severity or the perception that their child was ill had less impact on willingness to participate (16%). Parents who declined cited fear of research (19%), transportation problems (14%), and the demanding nature of the study (25%). Ultimately, 234 (21%) gave informed consent, with little variability of acceptance rates among sites. Importantly, the number of subjects enrolled correlated with the number of families that were approached. Sites that excluded patients based on clinical/psychosocial biases were not more successful in recruiting than those who approached all eligible subjects.

CONCLUSION

Large, demanding clinical trials require an adequate pool of potential participants. Approaching all potentially eligible patients without predetermined biases enhances success in recruitment.

The effects of hydroxycarbamide and magnesium on haemoglobin SC disease: results of the multi-centre CHAMPS trial

In a phase-II multi-centre double-blinded trial, we evaluated haematological effects of oral hydroxycarbamide (HC) and magnesium (Mg) in patients with HbSC, aged 5-53 years old. Subjects were randomized to HC + placebo, Mg + placebo, HC + Mg, or placebo + placebo. The primary endpoint was the proportion of hyperdense red blood cells after 8 weeks. Thirty-six subjects were evaluable, but the study was terminated early because of slow enrollment. In the combined HC groups, mean cell volume and HbF were increased, but differences were not seen in hyperdense red cells or vaso-occlusive events. Mg had no effects. Further investigation of hydroxycarbamide as monotherapy in HbSC disease is warranted.

Neutropenia at the time of subcutaneous port insertion may not be a risk factor for early infectious complications in pediatric oncology patients

BACKGROUND

The risk of infection associated with subcutaneous port (SQP) placement in patients with neutropenia remains unclear. We reviewed the rate of early infectious complications (<30 days) following SQP placement in pediatric oncology patients with or without neutropenia [absolute neutrophil count (ANC) <500/mm³].

METHODS

Baseline characteristics and infectious complications were compared between groups using univariate and multivariate analyses.

RESULTS

A total of 614 SQP were placed in 542 patients. Compared to nonneutropenic patients, those with neutropenia were more likely to have leukemia (n = 74, 94% vs n = 268, 50%), preoperative fever (n = 17, 22% vs n = 25, 5%), recent documented infection (n = 15, 19% vs n = 47, 9%), and were younger (81 vs 109 months) (p values <0.01). After adjusting for fever and underlying-disease, there was a nonsignificant association between neutropenia and early postoperative infection (OR 2.42, 95% CI 0.82-7.18, p = 0.11). Only preoperative fever was a predictor of infection (OR 6.09, 95% CI 2.08-17.81, p = 0.001).

CONCLUSION

SQP placement appears safe in most neutropenic patients.

TYPE OF STUDY

Retrospective comparative study.

LEVEL OF EVIDENCE

Level III.

Effect of intravenous vancomycin on renal function

In the past, vancomycin has been reported to cause renal failure during intravenous administration; however, more recently, such renal toxicity is alleged not to occur because of increased purity of the vancomycin preparations. In this study, 23 patients were prospectively examined during intravenous vancomycin administration for changes in renal function. Vancomycin was administered for an average of 15 days. The blood urea nitrogen (BUN) changes averaged +1.7 mg/dl and the creatinine changes averaged +0.06 mg/dl. Since the accuracy of the serum creatinine determination was +/- 0.3 mg/dl, clinically significant deterioration of renal function occurred in 4 patients or 17%. Even among these 4 patients with documented worsening of renal function, we suspect that deterioration was related to the infection being treated. With close monitoring of dosing, the propensity of vancomycin to cause nephrotoxicity may be less than once thought.

Hydroxyurea therapy associated with declining serum levels of magnesium in children with sickle cell anemia

OBJECTIVE

To obtain quantitative serum levels of total and ionized magnesium (Mg(2+)) in children with homozygous sickle cell anemia (SCA) undergoing therapy with hydroxyurea.

STUDY DESIGN

Five children, ages 11 to 14 years with homozygous SCA, were enrolled in a dose-escalating trial of hydroxyurea over an 18-month period. Serum levels of total and ionized magnesium together with ionized K(+), Na(+), and Ca(2+) were measured before hydroxyurea and every 6 months during hydroxyurea therapy.

RESULTS

Before treatment, 4 of the 5 patients had low or below-normal serum concentrations of Mg(2+) (normal range, 0.51-0.67 mmol/L). All 5 became Mg(2+)-deficient during hydroxyurea therapy, with no indication of recovery until after 12 to 18 months of drug administration (P <.05). Similar changes were noted for total magnesium concentrations. Mean serum levels of K(+), Na(+), and Ca(2+) remained consistently within normal ranges.

CONCLUSIONS

These findings warrant a controlled study of the effects of magnesium supplementation in patients with SCA receiving hydroxyurea. Potentially, such therapy could alleviate or prevent vaso-occlusive crises.

Splenic function is not maintained long-term after partial splenectomy in children with sickle cell disease

BACKGROUND

Partial splenectomy (PS) may allow preservation of splenic function in cases where splenectomy is indicated for hematologic diseases; however, the long-term outcomes are uncertain. We investigated the long-term outcomes of PS in patients with sickle cell disease (SCD).

METHODS

A single-institution retrospective chart review was performed for children with SCD who underwent PS from 1997 to 2017. For comparison, we reviewed outcomes for patients who underwent PS for hereditary spherocytosis (HS). The primary endpoint was viability of the splenic remnant as inferred by the presence of remnant perfusion on ultrasound and/or liver spleen scan.

RESULTS

Nine patients with SCD and 26 patients with HS underwent PS at a median age of 11 (IQR, 9-14) and 7.5 (IQR, 6-13) years, respectively. All underwent laparoscopic PS with three (7.9%) conversions to open. Two SCD patients were lost to long-term follow-up. The remaining seven SCD patients had initial postoperative splenic remnant perfusion demonstrated by ultrasonography. By 42 months postoperatively, however, none had a functioning splenic remnant. The median time to loss of splenic remnant was 12.6 (IQR 9.2-28.5) months. In contrast, all HS patients demonstrated robust splenic remnant blood flow with a median follow-up of 46 (IQR 37-82) months.

CONCLUSION

No patient with SCD who underwent PS had viable splenic tissue for more than 42 months, likely due to continued autoinfarction typical of patients with this disease. Therefore, we believe that PS to preserve splenic function is not indicated in patients with SCD.

LEVEL OF EVIDENCE

III.

Differences in obstetrical care and outcomes associated with the proportion of the obstetrician's shift completed

BACKGROUND

Understanding and improving obstetrical quality and safety is an important goal of professional societies, and many interventions such as checklists, safety bundles, educational interventions, or other culture changes have been implemented to improve the quality of care provided to obstetrical patients. Although many factors contribute to delivery decisions, a reduced workload has addressed how provider issues such as fatigue or behaviors surrounding impending shift changes may influence the delivery mode and outcomes.

OBJECTIVE

The objective was to assess whether intrapartum obstetrical interventions and adverse outcomes differ based on the temporal proximity of the delivery to the attending's shift change.

STUDY DESIGN

This was a secondary analysis from a multicenter obstetrical cohort in which all patients with cephalic, singleton gestations who attempted vaginal birth were eligible for inclusion. The primary exposure used to quantify the relationship between the proximity of the provider to their shift change and a delivery intervention was the ratio of time from the most recent attending shift change to vaginal delivery or decision for cesarean delivery to the total length of the shift. Ratios were used to represent the proportion of time completed in the shift by normalizing for varying shift lengths. A sensitivity analysis restricted to patients who were delivered by physicians working 12-hour shifts was performed. Outcomes chosen included cesarean delivery, episiotomy, third- or fourth-degree perineal laceration, 5-minute Apgar score of <4, and neonatal intensive care unit admission. Chi-squared tests were used to evaluate outcomes based on the proportion of the attending's shift completed. Adjusted and unadjusted logistic models fitting a cubic spline (when indicated) were used to determine whether the frequency of outcomes throughout the shift occurred in a statistically significant, nonlinear pattern RESULTS: Of the 82,851 patients eligible for inclusion, 47,262 (57%) had ratio data available and constituted the analyzable sample. Deliveries were evenly distributed throughout shifts, with 50.6% taking place in the first half of shifts. There were no statistically significant differences in the frequency of cesarean delivery, episiotomy, third- or fourth-degree perineal lacerations, or 5-minute Apgar scores of <4 based on the proportion of the shift completed. The findings were unchanged when evaluated with a cubic spline in unadjusted and adjusted logistic models. Sensitivity analyses performed on the 22.2% of patients who were delivered by a physician completing a 12-hour shift showed similar findings. There was a small increase in the frequency of neonatal intensive care unit admissions with a greater proportion of the shift completed (adjusted P=.009), but the findings did not persist in the sensitivity analysis.

CONCLUSION

Clinically significant differences in obstetrical interventions and outcomes do not seem to exist based on the temporal proximity to the attending physician's shift change. Future work should attempt to directly study unit culture and provider fatigue to further investigate opportunities to improve obstetrical quality of care, and additional studies are needed to corroborate these findings in community settings.