Health outcomes among offspring of US Coast Guard responders to the Deepwater Horizon oil spill, 2010-2011.

OBJECTIVE: To evaluate the potential for adverse health outcomes among infants born to US Coast Guard (USCG) responders to the Deepwater Horizon (DWH) oil spill disaster. METHODS: Department of Defense Birth and Infant Health Research programme data identified a cohort of singleton infants born 2010-2011 to USCG personnel in the DWH Oil Spill Coast Guard Cohort study. Infants were included if their military parent ('sponsor') responded to the oil spill during a selected reproductive exposure window (ie, 3 months preconception for male sponsors and periconception through pregnancy for female sponsors), or if their sponsor was a non-responder. χ2 tests and multivariable log-binomial regression were used to compare the demographic and health characteristics of infants born to spill responders and non-responders. RESULTS: Overall, 1974 infants with a male sponsor (n=182 responder, n=1792 non-responder) and 628 infants with a female sponsor (n=35 responder, n=593 non-responder) in the DWH Oil Spill Coast Guard Cohort were identified. Health outcomes were similar among the offspring of male responders and non-responders. The frequency of any poor live birth outcome (ie, low birth weight, preterm birth or birth defect) was higher among infants born to female responders (17.1%, n=6) than non-responders (8.9%, n=53); the maternal age-adjusted association was suggestively elevated (risk ratio 1.93, 95% CI 0.89 to 4.16). CONCLUSION: Infant health outcomes were comparable between the offspring of male USCG oil spill responders and non-responders. Findings were limited by the small number of infants identified, particularly among female responders, and should be interpreted with caution.

Validation of diagnosis codes for chorioamnionitis in medical encounter data, 2013-2018.

PURPOSE: Chorioamnionitis refers to intrauterine infection/inflammation that can be diagnosed clinically or from laboratory testing. This study aimed to validate chorioamnionitis International Classification of Diseases (ICD) codes using reference standards for clinical and histologic cases. METHODS: Department of Defense Birth and Infant Health Research program data identified a cohort of live deliveries at two United States military hospitals from 2013 to 2018. Deliveries were screened for chorioamnionitis using ICD codes from maternal delivery records; a sample of screen positive and negative deliveries was selected for chart review. Primary analyses validated deliveries using a reference standard for clinical chorioamnionitis; secondary analyses employed a reference standard that also included histologic cases, but were limited by temporal differences in availability of laboratory data. Sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were calculated with 95% confidence intervals (CIs). RESULTS: Overall, 1857 deliveries (465 screen positive, 1392 screen negative) were eligible for analysis and 336 met the reference standard for clinical chorioamnionitis, yielding a PPV of 0.68 (95% CI 0.63, 0.72) and sensitivity of 0.76 (95% CI 0.72, 0.81). In secondary analyses, 390 deliveries met the reference standard for clinical or histologic chorioamnionitis, resulting in an overall PPV of 0.75 (95% CI 0.71, 0.79); in 2018, when more laboratory results were available, the PPV was 0.91 (95% CI 0.84, 0.97). NPV and specificity were ≥0.97 across reference standards. CONCLUSIONS: Chorioamnionitis ICD codes exhibited moderate correlation with clinical disease, suggesting challenges in using medical encounter data to isolate clinical cases from those only identified through laboratory testing.

Pregnancy-associated and pregnancy-related deaths in the United States military, 2003-2014.

BACKGROUND: The Centers for Disease Control and Prevention has reported a steady increase in the US pregnancy-related mortality ratio since national surveillance began in 1987, although trends are partially induced by concurrent improvements in the identification of pregnancy-related deaths. No previous work has evaluated pregnancy-associated and pregnancy-related deaths among active-duty service members, a population with comprehensive health coverage and stable employment. OBJECTIVE: This study aimed to assess trends and variations in pregnancy-associated and pregnancy-related deaths in the US military. STUDY DESIGN: Live births to active-duty service members were captured in Department of Defense Birth and Infant Health Research program data from 2003 to 2014. Pregnancy-associated deaths (deaths temporally related to pregnancy from any cause) were identified through 1 year after pregnancy end date using National Death Index Plus data from the Joint Department of Defense and Department of Veterans Affairs Suicide Data Repository. Pregnancy-associated deaths were classified as pregnancy-related (causally related to pregnancy) based on cause-of-death codes in the National Death Index Plus data, administrative medical encounter data, and medical record review. Pregnancy-related deaths were reported including and excluding deaths from suicide and unintentional overdose. Mortality ratios (deaths per 100,000 live births) were reported overall, triennially, and by selected characteristics; the relative contribution of each cause of death to all pregnancy-associated deaths was reported overall and by age, race and ethnicity, and marital status. Timing of death relative to pregnancy end date was assessed by cause of death. RESULTS: A total of 179,252 live births occurred to active-duty service members from 2003 to 2014. Pregnancy-associated and pregnancy-related mortality ratios were 41.3 (95% confidence interval, 32.4-51.8) and 18.4 (95% confidence interval, 12.7-25.9), respectively. Excluding deaths from suicide and unintentional overdose, the pregnancy-related mortality ratio was 11.2 (95% confidence interval, 6.8-17.2). Deaths from suicide and unintentional overdose composed a larger proportion of pregnancy-related deaths over time and accounted for 17.6% of all pregnancy-associated deaths. Deaths from other pregnancy-related causes accounted for a greater share of deaths among older vs younger service members (≥30 years: 41.2%; 18-29 years: 22.8%) and non-Hispanic Black vs White service members (33.3% vs 24.1%). Pregnancy-related deaths, excluding suicide and unintentional overdose, were more likely to occur within 42 days of pregnancy end date; in contrast, deaths from suicide, overdose, assault, and undetermined intent were more likely to occur between 42 days and 1 year after pregnancy. CONCLUSION: Pregnancy-associated and pregnancy-related deaths varied over time and by age and race and ethnicity. Suicide and overdose are major recent causes of pregnancy-related death among active-duty service members.

Severe Maternal Morbidity among Women in the U. S. Military, 2003-2015.

OBJECTIVE: This study aimed to assess trends and correlates of severe maternal morbidity at delivery among active duty women in the U.S. military, all of whom are guaranteed health care and full employment. STUDY DESIGN: Linked military personnel and medical encounter data from the Department of Defense Birth and Infant Health Research program were used to identify a cohort of delivery hospitalizations among active duty military women from January 2003 through August 2015. Cases of severe maternal morbidity were identified by applying 21- and 20-condition algorithms (with and without blood transfusion) developed by the Centers for Disease Control and Prevention. Rates (per 10,000 delivery hospitalizations) were reported overall and by specific condition. Multivariable Poisson regression models estimated associations with demographic, clinical, and military characteristics. RESULTS: Overall, 187,063 hospitalizations for live births were included for analyses. The overall 21- and 20-condition severe maternal morbidity rates were 111.7 (n = 2089) and 37.4 (n = 699) per 10,000 delivery hospitalizations, respectively. The 21-condition rate increased by 184% from 2003 to 2015; the 20-condition rate increased by 40%. Compared with non-Hispanic White women, the adjusted 21-condition rate of severe maternal morbidity was higher for Hispanic (adjusted rate ratio [aRR] = 1.28, 95% confidence interval [CI]: 1.13-1.46), non-Hispanic Black (aRR = 1.34, 95% CI: 1.21-1.49), Asian/Pacific Islander (aRR = 1.35, 95% CI: 1.13-1.61), and American Indian/Alaska Native (aRR = 1.39, 95% CI: 1.06-1.82) women. Rates also varied by age, clinical factors, and deployment history. CONCLUSION: Active duty U.S. military women experienced an increase in severe maternal morbidity from 2003 to 2015 that followed national trends, despite protective factors such as stable employment and universal health care. Similar to other populations, military women of color were at higher risk for severe maternal morbidity relative to non-Hispanic White military women. Continued surveillance and further investigation into maternal health outcomes are critical for identifying areas of improvement in the Military Health System. KEY POINTS: · Cesarean delivery and multiple birth were the strongest correlates of severe maternal morbidity in this population.. · Racial disparities persisted across indicators of severe maternal morbidity.. · Rates of disseminated intravascular coagulation were higher than those reported nationally..

Validation of ICD-9-CM codes for major genitourinary birth defects in Military Health System administrative data, 2006-2014.

BACKGROUND: The Department of Defense Birth and Infant Health Research program is dedicated to birth defects research and surveillance among military families. Here, we assess and refine the validity of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for selected genitourinary birth defects in the Military Health System (MHS). We additionally outline methods for the calculation of positive predictive value (PPV) and negative predictive value (NPV), sensitivity, and specificity using a stratified sampling design. METHODS: Among military infants born from 2006 through 2014, a random sample of ICD-9-CM screen-positive cases (for six genitourinary birth defects) and screen-negative cases were selected for chart review. PPV, NPV, sensitivity, and specificity were calculated for individual defects and any included defect (i.e., overall); measures were weighted by the inverse probability of being sampled. RESULTS: Of 461,557 infants, 686 were sampled for chart review. Bladder exstrophy was accurately reported (PPV: >90%), while the accuracy of renal dysplasia, renal agenesis/hypoplasia, and hypospadias was moderate (PPVs: 66%-68%) and congenital hydronephrosis was low (PPV: 20%). Specificity and NPVs always exceeded 98%. The overall PPV was 50%; however, excluding congenital hydronephrosis screen-positive cases and requiring at least two inpatient or outpatient diagnostic codes resulted in a PPV of 85%. CONCLUSIONS: The validity of major genitourinary birth defect codes varied in MHS administrative data. The accuracy of an overall defect measure improved by omitting congenital hydronephrosis and requiring at least two diagnostic codes. Although PPV is generally useful for research, additional calculation of NPV, sensitivity, and specificity better informs the identification of appropriate selection criteria across surveillance and research settings.

The association of regional perinatal risk factors and neonatal intensive care capacity for Military Health System-insured newborns.

OBJECTIVE: To characterize hospitals where military-insured newborns received care and test the association of regional perinatal risk with neonatal intensive care unit (NICU) capacity. STUDY DESIGN: We identified birth hospitals for live newborns October 2015-December 2018 (n = 296,568) and assigned newborns to health service areas (HSAs). Perinatal risk factors and the number of neonatal special care beds and neonatologists were calculated at HSA levels. Cross-sectional correlation analyses assessed perinatal risk factors and capacity across HSAs. RESULTS: 27.0% (n = 10) of military birth hospitals had special care beds (intermediate and intensive) compared with 44.3% of civilian hospitals (n = 1224; p < 0.05). The number of special care beds and neonatologists per newborn varied more than twofold across regions and were only weakly associated with the proportion of higher risk newborns (R2 < 0.05). CONCLUSIONS: The lack of meaningful association of regional perinatal risk with NICU capacity poses challenges for effective specialized care among military-associated newborns.

History of pandemic H1N1-containing influenza vaccination and risk for spontaneous abortion and birth defects.

BACKGROUND: One recent study suggested an association between receipt of pandemic H1N1 (pH1N1)-containing vaccines in consecutive influenza seasons and spontaneous abortion, but corroborating scientific evidence is limited. In the present study, we leveraged a population of vaccine-compliant pregnant military women to examine history of pH1N1-containing influenza vaccination and adverse pregnancy outcomes. Because seasonal influenza vaccination is compulsory for military service, safety concerns regarding repeat vaccination are particularly relevant in this population. METHODS: Pregnancies and live births from Department of Defense Birth and Infant Health Research program data were linked with military personnel immunization records to identify women vaccinated with a pH1N1-containing vaccine in pregnancy prior to 21 6/7 weeks' gestation, October 2009-April 2015. Cox and modified Poisson regression models estimated associations between vaccination with pH1N1- versus non-pH1N1-containing influenza vaccine in the season prior to the index pregnancy, and spontaneous abortion and birth defects, respectively. Cox models were calculated for two periods of follow-up: through (1) 21 6/7 weeks' gestation and (2) 28 days postvaccination. RESULTS: Of 26,264 pregnancies, 21,736 (82.8%) were among women who received a dose of pH1N1-containing vaccine in the prior influenza season and 4,528 (17.2%) were among women who received non-pH1N1-containing vaccine in the prior influenza season. Among 23,121 infants, 19,365 (83.8%) and 3,756 (16.2%) had mothers exposed and unexposed to pH1N1-containing vaccine in the prior influenza season, respectively. The adjusted hazard ratio (aHR) for spontaneous abortion approximated 1.0 across the complete follow-up period (95% confidence interval [CI]: 0.89-1.13) and was slightly elevated when censored at 28 days postvaccination, though the CI was imprecise (aHR: 1.19; 95% CI: 0.97-1.46). No associations with birth defects were observed. CONCLUSION: This work lends additional safety evidence and support for vaccination against pH1N1 in pregnancy, regardless of the vaccine received in the prior influenza season.