Age, Sex, and Racial Differences in Neuroimaging Use in Acute Stroke: A Population-Based Study

BACKGROUND AND PURPOSE

Limited information is available regarding differences in neuroimaging use for acute stroke work-up. Our objective was to assess whether race, sex, or age differences exist in neuroimaging use and whether these differences depend on the care center type in a population-based study.

MATERIALS AND METHODS

Patients with stroke (ischemic and hemorrhagic) and transient ischemic attack were identified in a metropolitan, biracial population using the Greater Cincinnati/Northern Kentucky Stroke Study in 2005 and 2010. Multivariable regression was used to determine the odds of advanced imaging use (CT angiography/MR imaging/MR angiography) for race, sex, and age.

RESULTS

In 2005 and 2010, there were 3471 and 3431 stroke/TIA events, respectively. If one adjusted for covariates, the odds of advanced imaging were higher for younger (55 years or younger) compared with older patients, blacks compared with whites, and patients presenting to an academic center and those seen by a stroke team or neurologist. The observed association between race and advanced imaging depended on age; in the older age group, blacks had higher odds of advanced imaging compared with whites (odds ratio, 1.34; 95% CI, 1.12-1.61; P < .01), and in the younger group, the association between race and advanced imaging was not statistically significant. Age by race interaction persisted in the academic center subgroup (P < .01), but not in the nonacademic center subgroup (P = .58). No significant association was found between sex and advanced imaging.

CONCLUSIONS

Within a large, biracial stroke/TIA population, there is variation in the use of advanced neuroimaging by age and race, depending on the care center type.

Prepregnancy Weight in Women with Type I Diabetes Mellitus: Effect on Pregnancy Outcomes

Objective This study aims to evaluate the association between prepregnancy body mass index (BMI) and adverse pregnancy outcomes in women with type 1 diabetes mellitus (DM). Methods This is a secondary analysis of a cohort of 426 pregnancies in women with type 1 DM recruited before 20 weeks gestation. Women were categorized according to prepregnancy BMI: low BMI (< 20 kg/m²), normal BMI (20 to < 25 kg/m²), and high BMI (≥ 25 kg/m²). The outcomes of interest were: spontaneous abortion (delivery < 20 weeks gestation); preeclampsia; emergent delivery for maternal indications (hypertension or placental abruption); and preterm delivery (< 37 weeks gestation). Analyses included proportional hazards and multiple logistic regression models with covariates: age, age at diagnosis of type 1 DM, previous spontaneous abortion, microvascular disease (nephropathy or retinopathy), and glycohemoglobin A₁ concentrations. Results Low BMI was associated with preterm delivery. High BMI was associated with emergent delivery for maternal indications. Glycemic control as measured by glycohemoglobin A₁ was associated with increased risk of spontaneous abortion, attenuating the association with low prepregnancy weight. Conclusion Prepregnancy BMI is a risk factor to be considered when caring for women with type 1 DM, in particular for preterm delivery (low BMI) and emergent delivery for maternal indications (high BMI).

Health Status and Lifestyle Habits of US Medical Students: A Longitudinal Study

Background:

Evidence shows that physicians and medical students who engage in healthy lifestyle habits are more likely to counsel patients about such behaviors. Yet medical school is a challenging time that may bring about undesired changes to health and lifestyle habits.

Aims:

This study assessed changes in students' health and lifestyle behaviors during medical school.

Subjects and Methods:

In a longitudinal study, students were assessed at both the beginning and end of medical school. Anthropometric, metabolic, and lifestyle variables were measured at a clinical research center. Data were collected from 2006 to 2011, and analyzed in 2013–2014 with SAS version 9.3. Pearson's correlations were used to assess associations between variables and a generalized linear model was used to measure change over time.

Results:

Seventy-eight percent (97/125) of participants completed both visits. At baseline, mean anthropometric and clinical measures were at or near healthy values and did not change over time, with the exception of increased diastolic blood pressure (P = 0.01), high-density lipoprotein-cholesterol (P < 0.001), and insulin (P < 0.001). Self-reported diet and physical activity habits were congruent with national goals, except for Vitamin D and sodium. Dietary intake did not change over time, with the exceptions of decreased carbohydrate (percent of total energy) (P < 0.001) and sodium (P = 0.04) and increased fat (percent of total energy) and Vitamin D (both P < 0.01). Cardiovascular fitness showed a trend toward declining, while self-reported physical activity increased (P < 0.001).

Conclusions:

Students' clinical measures and lifestyle behaviors remain generally healthy throughout medical school; yet some students exhibit cardiometabolic risk and diet and activity habits not aligned with national recommendations. Curricula that include personal health and lifestyle assessment may motivate students to adopt healthier practices and serve as role models for patients.

Population-based study of wake-up strokes

OBJECTIVE

Previous studies have estimated that wake-up strokes comprise 8%to 28% of all ischemic strokes, but these studies were either small or not population-based. We sought to establish the proportion and event rate of wake-up strokes in a large population-based study and to compare patients who awoke with stroke symptoms with those who were awake at time of onset.

METHODS

First-time and recurrent ischemic strokes among residents of the Greater Cincinnati/Northern Kentucky region (population 1.3 million) in 2005 were identified using International Classification of Diseases-9 codes 430-436 and verified via study physician review. Ischemic strokes in patients aged 18 years and older presenting to an emergency department were included. Baseline characteristics were ascertained, along with discharge modified Rankin Scale scores and 90-day mortality.

RESULTS

We identified 1,854 ischemic strokes presenting to an emergency department, of which 273 (14.3%) were wake-up strokes. There were no differences between wake-up strokes and all other strokes with regard to clinical features or outcomes except for minor differences in age and baseline retrospective NIH Stroke Scale score. The adjusted wake-up stroke event rate was 26.0/100,000. Of the wake-up strokes, at least 98 (35.9%) would have been eligible for thrombolysis if arrival time were not a factor.

CONCLUSIONS

Within our population, approximately 14% of ischemic strokes presenting to an emergency department were wake-up strokes. Wake-up strokes cannot be distinguished from other strokes by clinical features or outcome. We estimate that approximately 58,000 patients with wake-up strokes presented to an emergency department in the United States in 2005.

Consequences of smoking and caffeine consumption during pregnancy in women with type 1 diabetes

OBJECTIVE

To test the hypothesis that, in women with type 1 diabetes, prenatal smoking and caffeine consumption during pregnancy are associated with an increased risk of adverse maternal and perinatal outcomes.

METHODS

A secondary analysis of data on pregnant women with type 1 diabetes from an interdisciplinary program of Diabetes in Pregnancy. Women were interviewed monthly, by a trained non-medical member of the research team, using a standardized questionnaire, to ascertain daily smoking habits and caffeine consumption.

RESULTS

Smoking and caffeine information were available on 191 pregnancies, 168 progressing beyond 20 weeks of gestation. Early pregnancy smoking (OR 3.3, 95% CI 1.2, 8.7) and caffeine consumption (OR 4.5, 95% CI 1.2, 16.8) were associated with increased risk of spontaneous abortion when controlling for age, years since diagnosis of diabetes, previous spontaneous abortion, nephropathy and retinopathy. Smoking throughout pregnancy was significantly associated with decreased birth weight and prolonged neonatal hospital stay. Smoking throughout pregnancy (OR 0.2, 95% 0.1, 1.0) and caffeine consumption after 20 weeks (OR 0.3, 95% CI 0.1, 1.0) were associated with reduced risk of pre-eclampsia.

CONCLUSIONS

Caffeine consumption during early pregnancy, regardless of glycemic control, increases the risk of spontaneous abortion. Smoking throughout pregnancy and caffeine consumption are associated with reduced risk of pre-eclampsia.

Pregnancy outcome and progression of diabetic nephropathy. What's next?

OBJECTIVES

The first objective was to assess the association of renal function with maternal and fetal pregnancy outcome in women with diabetic nephropathy. The second objective was to examine the feasibility of a multicenter surveillance program to determine the rates of maternal and fetal pregnancy complications in women with diabetic nephropathy, and to study the effect of pregnancy on the natural history of diabetic renal disease.

METHODS

In order to address the first objective, we analyzed data from women with type 1 diabetes and nephropathy enrolled in the Diabetes in Pregnancy Program at our institution. Women were assigned to one of three groups according to enrolment serum creatinine concentration: < or = 1.0 mg/dl, > 1.0 to 1.5 mg/dl and > 1.5 mg/dl. A pilot surveillance program at six centers included women experiencing pregnancy complicated by diabetic nephropathy. In both studies, medical and obstetric history, and maternal and neonatal outcomes, were recorded. Statistical analysis included chi2, logistic regression and analysis of variance.

RESULTS

There were 72 pregnancies in 58 women with diabetic nephropathy who enrolled in the pregnancy program. High serum creatinine concentration at enrolment was associated with delivery before 32 weeks' gestation, very low birth weight and increased incidence of neonatal hypoglycemia, independent of quantity of total urinary protein excretion and glycemic control in any trimester. To date, pilot surveillance data have been obtained from six centers on 16 women. Serum creatinine concentrations ranged from 0.4 to 1.1 mg/dl and creatinine clearance from 32 to 317 m/min. Gestational age at delivery ranged from 22 to 39 weeks.

CONCLUSIONS

High serum creatinine concentration at enrolment is a risk factor for adverse maternal and neonatal outcome, independent of quantity of total urinary protein excretion and glycemic control during any trimester. A multicenter surveillance program is needed, in order to study less frequent maternal and neonatal outcomes as well as the long-term effects of pregnancy on the natural course of diabetic renal disease.

Does the combined antenatal use of corticosteroids and antibiotics increase late-onset neonatal sepsis in the very low birth weight infant?

OBJECTIVE

The purpose of this study was to determine whether the combined use of maternal antenatal corticosteroids and antibiotic therapy is associated with an increased risk of late-onset neonatal sepsis among very low birth weight infants.

STUDY DESIGN

The outcomes of infants admitted to the 3 Cincinnati neonatal intensive care units between May 1991 and May 2000 were retrospectively evaluated. Late-onset neonatal sepsis was defined either as the occurrence of a positive blood culture obtained after 72 hours of life with clinical signs of sepsis or as the need for >5 consecutive days of antibiotic therapy for presumed sepsis that initiated after 72 hours of life. Wilcoxon rank sum, chi-square test, and multiple logistic regression were used for analysis.

RESULTS

Among the parturients delivering the study infants, 434 women (24%) received corticosteroids only, 175 women (9%) received antibiotics only, 819 women (46%) received both corticosteroids and antibiotics, and 370 women (20%) received neither corticosteroids nor antibiotics. Among 1978 study infants, there were 732 infants (41%) with late-onset neonatal sepsis. By univariate analysis, the odds ratio for late-onset neonatal sepsis caused by combined corticosteroid and antibiotic use was 0.96 (95% CI, 0.89%, 1.04%). Multiple logistic regression analysis was used to evaluate the risk of combined corticosteroids and antibiotic use after controlling for potential covariates and confounders. After controlling for outborn birth (odds ratio, 1.3; 95% CI, 1.0%-1.8%), increasing gestational age at delivery (odds ratio, 0.63; 95% CI, 0.60%-0.66%), interaction between white race and male gender (P =.01) and interaction between antibiotics and prolonged rupture of membranes (P =.02), the use of corticosteroids and antibiotics was not associated with an increased risk of late-onset neonatal sepsis (P =.9).

CONCLUSION

The combined use of maternal corticosteroids and antibiotic therapy is not associated with an increased risk for late-onset neonatal sepsis.

A comparison of various routes and dosages of misoprostol for cervical ripening and the induction of labor

OBJECTIVE

The purpose of this study was to compare the efficacy of different routes of misoprostol administration for cervical ripening and the induction of labor.

STUDY DESIGN

Three hundred thirty women at > or = 32 weeks gestation with a Bishop score < or = 6 and an indication for induction were randomized to 1 of 3 double-blinded groups: (1) 25 microg orally administered misoprostol plus 25 microg vaginally administered misoprostol, (2) orally administered placebo plus 25 microg vaginally administered misoprostol, or (3) 25 microg orally administered misoprostol plus vaginally administered placebo. Doses were repeated every 4 hours until onset of labor or a maximum of 12 doses were given. The primary outcome of the trial was vaginal delivery within 24 hours of the initiation of induction. Secondary outcomes were the time from induction to delivery, need for oxytocin augmentation, mode of delivery, frequency of side effects, and neonatal and maternal outcome. Analysis of variance, chi-square test, and logistic regression were used for analysis.

RESULTS

There were no significant differences in maternal characteristics or indications for induction. The percentage of women who achieved vaginal delivery within 24 hours was highest in the vaginally administered misoprostol group: 67% compared with 53% in the oral-plus-vaginal group (P < .05) and 36% in the oral group (P < .05). The median time to vaginal delivery was shorter in the vaginal and oral-plus-vaginal misoprostol groups, 13.5 hours and 14.3 hours, respectively, when compared with 23.9 hours in the oral group (P < .05). The rate of cesarean delivery was lowest in the vaginal misoprostol group (17% compared with 30% in the oral-plus-vaginal group and 32% in the oral group; P < .05). Uterine tachysystole occurred least frequently in the oral misoprostol group (10% compared with 32% in the vaginal group and 34% in the oral-plus-vaginal group; P < .05). Uterine hyperstimulation also occurred least frequently in the oral misopro-stol group (4% compared with 15% in the vaginal group and 22% in the oral-plus-vaginal group; P < .05).

CONCLUSION

At the doses studied, induction of labor with vaginally administered misoprostol is more efficacious than either oral-plus-vaginal or oral-only route of administration.

Leptin in the ovine fetus correlates with fetal and placental size

OBJECTIVE

The purpose of this study was to detect the presence of leptin and its receptor in ovine fetal tissues and to examine the relationship between circulating leptin concentrations and fetal and placental weights on gestational day 138 (GD138) of ovine pregnancy (term, 145 days).

STUDY DESIGN

Pregnant sheep (n = 18) were instrumented on GD 110 to facilitate measurement and chronic reduction of uterine blood flow and produce intrauterine growth restriction. Four animals that served as controls were euthanized on GD 138 to obtain fetal tissues to determine the presence of ovine leptin and its receptor by reverse transcriptase-polymerase chain reaction. Seven instrumented animals were randomized into the control group, and 7 instrumented animals were randomized into the uterine blood flow restricted group (reduction equaled approximately 50% on GD 138). Maternal and fetal blood samples were obtained on day 138 to measure plasma leptin concentrations, and animals were euthanized for the determination of fetal morphometrics and placental weight.

RESULTS

Expression of RNA for ovine leptin and its receptor were observed in fetal liver, skeletal muscle, kidney, heart, and placenta. Fetal body weight, ponderal index, and placental weight were significantly decreased by approximately 40% in the blood flow restricted group as compared with controls. Fetal leptin concentrations were increased by 45% in the uteroplacental blood flow restricted group (P =.01). Maternal leptin concentrations were not significantly different between the 2 groups and did not correlate with fetal concentrations. Fetal leptin concentrations had an inverse relationship with uterine blood flow (r = -0.73; P =.004), fetal body weight (r = -0.78; P =.002), and placental weight (r = -0.68; P =.01).

CONCLUSION

Ovine fetal tissues express RNA for leptin and its receptor. Circulating leptin concentrations in the ovine intrauterine growth restriction fetus were significantly elevated on gestational day 138 compared with controls. Fetal leptin concentrations were inversely related to uterine blood flow and fetal and placental weight. These findings suggest that fetal leptin may be involved in an adaptive response to intrauterine growth restriction.

Fetal weight and progression of diabetic retinopathy

OBJECTIVE

To test the hypothesis that progression of diabetic retinopathy in pregnancy is associated with reduced fetal growth and related neonatal morbidity.

METHODS

Women with type 1 diabetes (n = 205) were enrolled before 14 weeks' gestation in a prospective study of diabetes in pregnancy and treated with intensive insulin therapy. They had serial ophthalmologic evaluations before 20 weeks' gestation and in late gestation or postpartum. Subjects were divided into two groups based on whether retinopathy progressed (progression group) or remained unchanged (no progression group).

RESULTS

Retinopathy progressed in 59 of 205 women (29%) and was associated with advanced White classification (P =.001): three (5%) were class B, 14 (23%) class C, 24 (41%) class D, and 18 (30%) class F-RF. Reduced fetal growth was associated with progression of retinopathy. Mean birth weight was lower (P =.02), and more infants were small for gestational age (P =.02) and had low birth weights (P =.02) in the progression group. More large-for-gestational-age infants were noted in the no-progression group (P =.04). Birth weight percentile distributions showed a shift of the curve to the left in the progression group (P =.03). There were no differences in gestational age at delivery, macrosomia, preterm delivery, respiratory distress syndrome, neonatal hypoglycemia, or neonatal death. Small for gestational age was associated with chronic hypertension (odds ratio [OR] 6.4; 95% confidence interval [CI] 1.5, 27.9) and retinopathy progression (OR 4.7; 95% CI 1.2, 23.8).

CONCLUSION

Development and progression of diabetic retinopathy during pregnancy were associated with reduced fetal growth manifested as increased rate of small-for-gestational-age and low-birth-weight infants.

Dietary fiber intakes and insulin requirements in pregnant women with type 1 diabetes

OBJECTIVE

To determine whether higher dietary fiber intake (water soluble and insoluble) is associated with lower insulin requirements and better glycemic control in pregnant women with type 1 diabetes consuming a self-selected diet.

DESIGN

A longitudinal, observational study.

SUBJECTS

Pregnant women (n=141) with type 1 diabetes participating in an interdisciplinary program examining the effects of glycemic control on pregnancy outcome (Diabetes and Pregnancy Program, University of Cincinnati Medical Center).

MEASUREMENTS

We determined total, water soluble and insoluble fiber intakes from 3-day food records kept each trimester during pregnancy. Outcome measures were insulin dose, pre-meal blood glucose, and glycated hemoglobin concentrations.

STATISTICAL ANALYSES

Correlation coefficients, multiple regression, mixed-model analysis of variance.

RESULTS

Mean intakes (g/day) of total, water soluble fiber, and insoluble fiber were 14.0 (range, 1.8-33.1), 4.8 (range, 0.6-10.5) and 9.0 (range, 1.1-24.0), respectively. In the second and third trimesters of pregnancy, insulin requirements were inversely associated with total, water soluble, and insoluble fiber intakes; the correlation coefficients ranged from -0.22 to -0.17 (P=.02 to .08). Insulin requirements associated with a higher fiber intake (20.5 g/day) were 16% to 18% lower than for a lower fiber intake (8.1 g/day). These relations remained after adjustment for body weight, disease severity and duration, insulin type, and study year in the second (P=.03 to .10) but not in the third trimester. Pre-meal blood glucose and glycated hemoglobin concentrations were not associated with fiber intake.

CONCLUSIONS

Among pregnant women with type 1 diabetes, higher fiber intake is associated with lower daily insulin requirements. Dietary fiber intake should be considered when counseling patients about the management of blood glucose concentrations.

Temporal changes in brain volume and cognition in a randomized treatment trial of vascular dementia

OBJECTIVE

To measure changes in brain and ischemic volume over time by magnetic resonance imaging (MRI) as part of a randomized treatment trial of vascular dementia.

METHODS

Participants who met criteria for vascular dementia underwent comprehensive neurological and neuropsychological testing on entrance, during, and at completion of the 1-year study. For those centers who had easily available MRI, MRI of the brain was to be performed on entry and completion of the study. Image analysis was performed on all balanced and T2-weighted MR films to determine ventricular, sulcal, ischemic, and hemispheric brain volumes.

RESULTS

Of the 105 patients who met the criteria for vascular dementia, 40 had a baseline MRI study that met protocol requirements and was of excellent image quality. The baseline ventricular volume in these 40 patients with high-quality MR correlated with most measures of cognitive and behavioral function, including the total Alzheimer's Disease Assessment Score (ADAS) (r = 0.51, P = .0024), as well as activities of daily living (r = 0.61, P = .0002). The baseline ischemic brain volume correlated well only with the gait and postural stability scale (r = 0.74, P = .009). Of the 40 participants, 25 had MRI studies at baseline and at completion of the study that were comparable and of excellent image quality. For these 25 patients, the mean ventricular volumes increased by 9% over the study year (P = .001) and the mean ischemic brain volume increased by 18% (P = .01). Temporal changes in the sulcal and nonischemic brain volume did not reach significance. None of the 14 clinical score measures changed significantly between baseline and completion of the study in these 25 patients.

CONCLUSION

In summary, ventricular volume correlated well with cognitive measures in patients with vascular dementia and was a more sensitive marker for change during the study year than the clinical scales used in this study. This study also points out the practical limitations of brain imaging as a surrogate measure of clinical outcome in multicenter randomized treatment trials of brain disease.

A focused preconceptional and early pregnancy program in women with type 1 diabetes reduces perinatal mortality and malformation rates to general population levels

OBJECTIVE

To evaluate the impact of a focused preconceptional and early pregnancy program specializing in the care of women with Type 1 diabetes on perinatal mortality and congenital malformations.

METHODS

This clinical study included women with Type 1 diabetes in an interdisciplinary Diabetes in Pregnancy Program Project Grant (PPG) funded by the NIH (1978-1993); these women were enrolled preconceptionally or during the first trimester (up to 14 weeks) and had pregnancies continuing beyond 20 weeks gestation. Strict glucose control was implemented and adherence assessed. Antepartum fetal surveillance was started at 32 weeks gestation. All live-born infants and stillbirths were examined. A retrospective comparison analysis of the period before PPG I (1973-1978) and after cessation of funding (1993-1999) was performed, specifically evaluating perinatal mortality and congenital malformation rates. Data were analyzed using analysis of variance, chi2, and Fisher's exact test.

RESULTS

Three hundred and six women were enrolled in three 5-year periods: PPG I (1978-1983) n = 111, PPG II (1983-1988) n = 103, and PPG III (1988-1993) n = 92. Entry and interval glycohemoglobin A1 concentrations obtained decreased with each consecutive PPG. An emphasis on preconception care began in 1984, with preconception enrollment reaching 23% for PPG II and increasing in PPG III to 37%. As preconception enrollment increased, perinatal mortality rate decreased from 3% for PPG I and 2% for PPG II, to 0% in PPG III, and the congenital malformation rate decreased to a low 2.2% by PPG III. Comparison data collected for the period before PPG 1 (1973-1978) n = 79 revealed a perinatal mortality rate of 7% and a congenital malformation rate of 14%. Also, a postprogram retrospective analysis of the period 1993-1999 (n = 82) revealed an increase in perinatal mortality, with one death compared to none in PPG III, and a congenital malformation rate of 3.65% compared to 2.2% during PPG III. The preconception enrollment for this period decreased (19.5%).

CONCLUSIONS

A program emphasizing preconceptional care, strict glycemic control preconceptionally and throughout gestation, and the use of antepartum fetal surveillance was associated with a significant decrease in the rate of perinatal mortality and congenital malformations in infants of women with Type 1 diabetes. However, ongoing improved outcome appears to depend on the availability of funding for a specialized preconception program.

The effect of early discharge after vaginal delivery on neonatal readmission rates

OBJECTIVE

To determine the effect of a structured program for early neonatal discharge from a tertiary medical center on the risk of neonatal readmission.

METHODS

An early-discharge program was instituted at our tertiary medical center in July 1993, with the objective of discharging mothers and infants within 24 hours after vaginal birth. The readmission rate of vaginally delivered infants during the early-discharge period (July 1, 1993, through March 31, 1995) was compared with the rate during a conventional-discharge period (January 1, 1992, through June 30, 1993). Analyses were performed to examine two groups within the early-discharge group: those discharged within 24 hours of vaginal delivery; and those discharged within 1 hospital day of vaginal delivery.

RESULTS

During the early-discharge period, 1.24% of neonates were readmitted within 10 days of birth, compared with 1.35% during the conventional-discharge period. In the early-discharge period group, infants born vaginally and discharged within 24 hours of birth had a readmission rate of 1.46% compared with 1.14% for those who stayed longer than 24 hours after delivery. Similarly, the readmission rate was no different for infants who were discharged within 1 hospital day. The primary indications for readmission in both periods were infections and jaundice.

CONCLUSION

Implementation of a structured program for early neonatal discharge does not have an association with increased risk of neonatal readmission to the hospital.

Deficient counterregulation: a possible risk factor for excessive fetal growth in IDDM pregnancies

OBJECTIVE

The rate of macrosomia in infants born to women with IDDM remains high despite intensive insulin therapy and good glycemic control. We hypothesized that one of the factors contributing to this high rate of macrosomia is deficient counterregulatory hormonal responses to hypoglycemia.

RESEARCH DESIGN AND METHODS

Hypoglycemia was induced in 17 women with IDDM and 10 normal control subjects at 24-28 and at 32-34 weeks' gestation, using the hypoglycemic clamp technique. Plasma glucose concentrations were decreased to 3.3 mmol/l and maintained at this level for 1 h. Blood samples were drawn every 15 min for measurement of counterregulatory hormone concentrations.

RESULTS

All 17 women with IDDM had diminished epinephrine responses to hypoglycemia, compared with control subjects. Eight of the women with IDDM (nonresponders) had minimal or no responses (< 165 pmol/l above baseline) and nine women (responders) had a moderate response (244-764 pmol/l). Of the eight nonresponders, seven had large infants (birth weight in the upper quartile), while only three of the nine responders had large infants (P < 0.05).

CONCLUSIONS

Severely impaired counterregulatory epinephrine responses to hypoglycemia in pregnant women with IDDM may be a factor contributing to excessive fetal growth. We speculate that in these women, recurrent episodes of hypoglycemia may result in frequent bouts of increased caloric intake, with repeated episodes of transient hyperglycemia leading to fetal hyperinsulinism and excessive fetal growth.

Counterregulatory hormonal responses to hypoglycemia during pregnancy

OBJECTIVE

To evaluate the counterregulatory responses to insulin-induced hypoglycemia in healthy women and in women with insulin-dependent diabetes during pregnancy and in the nonpregnant state.

METHODS

Hypoglycemia was induced using the hypoglycemic clamp technique in 17 women with insulin-dependent diabetes and in ten healthy controls, both in the nonpregnant state (study 1), at 24-28 weeks' gestation (study 2), and at 32-34 weeks' gestation (study 3). Plasma glucose concentrations were decreased to 60 mg/dL and maintained at this level for 1 hour. Blood samples were drawn every 15 minutes to measure epinephrine, glucagon, growth hormone, and cortisol concentrations. Statistical analyses compared counterregulatory responses between women with and without diabetes, and between the pregnant and nonpregnant state.

RESULTS

Women with diabetes had significantly diminished peak epinephrine responses to hypoglycemia compared with controls (mean +/- standard error of the mean [SEM]): 52 +/- 11 versus 191 +/- 42 pg/mL in study 1, 30 +/- 9 versus 102 +/- 47 pg/mL in study 2, and 38 +/- 10 versus 148 +/- 38 pg/mL in study 3 (P < .05). Their responses during pregnancy were also diminished compared with their own nonpregnant epinephrine responses. Women with diabetes also had no recognizable cortisol or glucagon responses to hypoglycemia, and in healthy controls the glucagon responses were significantly diminished during pregnancy compared with their own nonpregnant responses. In both groups, growth hormone responses (mean +/- SEM) diminished progressively during pregnancy from study 1 (14.6 +/- 2.5 and 12.5 +/- 5.2 ng/mL) to study 2 (4.4 +/- 1.1 and 7.3 +/- 2.7 ng/mL) to study 3 (2.5 +/- 0.9 and 4.4 +/- 2.3 ng/mL) in women with diabetes and in controls, respectively.

CONCLUSION

Counterregulatory epinephrine and growth hormone responses to hypoglycemia are diminished in women with insulin-dependent diabetes during pregnancy. This may be due, in part, to an independent effect of pregnancy, contributing to the increased incidence of hypoglycemia in these patients during pregnancy.

Does pregnancy increase the risk for development and progression of diabetic nephropathy?

OBJECTIVE

This study was designed to determine whether pregnancy and increasing parity in women with insulin-dependent diabetes mellitus (1) increases the risk for diabetic nephropathy and (2) accelerates the progression of diabetic nephropathy.

STUDY DESIGN

The study included women with insulin-dependent diabetes mellitus who enrolled in our diabetes-in-pregnancy trial with a pregnancy that continued beyond 20 weeks' gestation and who were delivered between 1978 and December 31, 1991, to allow for a minimum of 3 years' follow-up. Pregnancy and follow-up information was obtained from the medical records and from our computerized database. For patients followed up elsewhere, information was obtained from their current physicians. Life-table analysis was used to determine (1) the risk for nephropathy developing de novo as a function of duration of disease and the association of this risk with parity and (2) the risk of renal failure developing in women with preexisting nephropathy and its association with parity.

RESULTS

The study population included 182 pregnant women with insulin-dependent diabetes mellitus: 46 with overt nephropathy (group F) and 136 without nephropathy (group NF). Pregnancy and increasing parity did not increase the overall risk for nephropathy (44% after 27 years of diabetes). In group NF 10% had nephropathy within 10.1 +/- 4.2 years of the pregnancy. Proteinuria appearing during pregnancy and glycemic control during pregnancy were significantly associated with the subsequent development of nephropathy. In group F 26% had end-stage renal disease after a median period of 6 years from the pregnancy. Pregnancy or increasing parity did not increase the risk for renal failure in women with nephropathy.

CONCLUSIONS

Our data support the premise that pregnancy in women with insulin-dependent diabetes mellitus does not increase the risk of subsequent nephropathy and does not accelerate progression of renal disease in women with preexisting nephropathy.

Hypoglycemia: the price of intensive insulin therapy for pregnant women with insulin-dependent diabetes mellitus

OBJECTIVE

To evaluate the risk of hypoglycemia associated with intensive insulin therapy of type I diabetes during pregnancy.

METHODS

Eighty-four women with type I diabetes were recruited before 9 weeks' gestation and received intensive insulin therapy throughout pregnancy. Patients monitored glucose concentrations with memory glucometers, and insulin dosages were adjusted weekly accordingly. A detailed history of clinical hypoglycemic events was obtained at each weekly clinic visit.

RESULTS

Clinically significant hypoglycemia requiring assistance from another person occurred in 71% of pregnant patients, with a peak incidence between 10-15 weeks. Severe hypoglycemia during the early weeks of embryogenesis was not associated with an increase in embryopathy. Glycemic control was similar in women with or without recurrent hypoglycemia, but glucose fluctuations were significantly greater in hypoglycemic women.

CONCLUSION

Severe hypoglycemia is a significant maternal risk associated with intensive insulin therapy of pregnant women with type I diabetes. In women with recurrent episodes of hypoglycemia, the clear benefits of strict glycemic control must be weighed against the hazards of hypoglycemia.

A longitudinal study describing confidence limits of normal fetal cardiac, thoracic, and pulmonary dimensions from 20 to 40 weeks' gestation

The current prospective, longitudinal study was designed to define the confidence limits and characteristics of growth for fetal cardiac, thoracic, and pulmonary dimensions from 20 to 40 weeks' gestation. We tested the hypotheses that (1) CC/TC, (2) CC/AC, (3) TC/HC, and (4) TC/AC ratios remain constant throughout this period of gestation. The four-chamber view of the fetal heart in diastole, in the absence of fetal breathing, was used as a standard reference for sonographic measurement of cardiac, thoracic, and left and right pulmonary dimensions in a longitudinal study of 45 uncomplicated pregnancies. Cardiac growth is best fit by a quadratic function: -8.147 + 0.900 (GA) - 0.0078 (GA)2. Similarly, thoracic growth is best fit by a quadratic function: -14.072 + 1.757 (GA) - 0.018 (GA)2. The characteristics of growth of the left and right lungs are best described by linear growth equations: -1.71 + 0.426 (GA) and -1.62 + 0.539 (GA), respectively. Each of the CC/TC, CC/AC, TC/HC, and TC/AC ratios changed significantly over time.

Early-pregnancy proteinuria in diabetes related to preeclampsia

OBJECTIVE

To test the hypothesis that the risk of preeclampsia in diabetic mothers is increased with incipient diabetic nephropathy as well as with overt nephropathy.

METHODS

Pregnancy outcome was studied in 311 women with class B-RF diabetes from two institutions. Using 104 women without chronic hypertension followed at the University of California, San Francisco, we constructed a receiver-operating characteristic curve relating 24-hour urinary total protein before 20 weeks' gestation to the subsequent development of preeclampsia. From the curve, a predictive cutoff level of proteinuria was selected and tested in two validation groups not used to construct the curve: 158 women without chronic hypertension followed at the University of Cincinnati and 49 women with chronic hypertension from both institutions.

RESULTS

The receiver-operating characteristic curve showed an increased risk of preeclampsia with early-pregnancy proteinuria of 190 mg/day or more. In the Cincinnati validation group, the rate of preeclampsia was 7% in women with early-pregnancy proteinuria of less than 190 mg/day, 31% with proteinuria of 190-499 mg/day, and 38% with proteinuria of 500 mg/day or more. In the chronic-hypertension validation group, the rates were 0, 50, and 58%, respectively. By multiple logistic regression, the increased risk of preeclampsia with proteinuria above 190 mg/day persisted after controlling for the effects of parity, chronic hypertension, retinopathy, and glycemic control.

CONCLUSIONS

Diabetic gravidas with early-pregnancy proteinuria of 190-499 mg/day are at increased risk for preeclampsia. The risk is comparable to that in women with overt diabetic nephropathy and is independent of chronic hypertension. We speculate that diabetic women with proteinuria in this range have incipient or subclinical diabetic nephropathy.

Significance of obesity on nutritional, immunologic, hormonal, and clinical outcome parameters in burns

OBJECTIVE

The potential additive effect of obesity on selected nutritional, immunologic, hormonal, and clinical outcome parameters was evaluated.

DESIGN

Fifteen obese patients were randomly matched for age, percentage of burn, percentage of third-degree burn, and inhalation injury to 15 nonobese patients.

SETTING

Subjects were admitted to Shriners Burns Institute or University Hospital in Cincinnati, Ohio.

RESULTS

The results of this study established a significant relationship between obesity and morbidity. Incidence of infection was greatest in the obese group (P < .03). Bacteremia (P < .008) and clinical sepsis (P < .005) occurred concomitant with obesity. The obese group required significantly (P < .05) more days on mechanical ventilatory support. Exogenous insulin supplementation (obese = 14.5 +/- 5.3 days, nonobese = 6.2 +/- 2.2 days) and antibiotic therapy (obese = 8.5 +/- 2.3 days, nonobese = 3.4 +/- 1.5 days) were required more than twice as many days in the obese group, although these trends did not reach statistical significance. Resting energy expenditure measurements were significantly higher in the obese group during weeks 1 (P < .0006) and 2 (P < .02), and the trend continued into weeks 3 and 4. Transferrin values for the obese group remained suppressed throughout the first 4 weeks after the burn, whereas the transferrin levels of the nonobese group were normal by week 4. Compared with normal-weight burn patients, obese burn patients had markedly lower alpha 2-macroglobulin values and higher glucagon levels throughout the study period.

APPLICATIONS/CONCLUSIONS

The data demonstrate the many metabolic and biochemical aberrations associated with obesity, distinct from the burn injury itself, and suggest that the overweight burn patient is at increased risk of morbidity. Given the prevalence of obesity in the United States, greater attention clearly needs to be given to its prevention and management.

Elective induction versus spontaneous labor after sonographic diagnosis of fetal macrosomia

OBJECTIVE

To test the hypothesis that elective induction of labor, compared to spontaneous labor, reduces the cesarean rate in women with a sonographic diagnosis of fetal macrosomia.

METHODS

Sonography results over a period of 27 months were used to select 262 consecutive patients who met the following inclusion criteria: singleton pregnancy at term, estimated fetal weight (EFW) at the 90th percentile or greater, and delivery at our institution. The subjects were divided into four groups based on obstetric management: spontaneous labor (N = 115), elective induction of labor with macrosomia as the sole indication (N = 44), induction of labor for other maternal or fetal indications (N = 48), and elective cesarean delivery (N = 55). The analysis focused on the first two groups. These were compared regarding cesarean rate, indications for cesarean, and shoulder dystocia rate. Multiple logistic regression was used to control for potential confounders.

RESULTS

With elective induction, the cesarean rate was 57%, significantly higher than the 31% rate with spontaneous labor (P < .01). The induced group also had a significantly higher EFW and birth weight. When logistic regression was used to control for birth weight, parity, and care provider, elective induction was still associated with a higher risk of cesarean delivery than was spontaneous labor (adjusted odds ratio 2.7, 95% confidence interval 1.2-5.9; P < .02). Shoulder dystocia occurred in one of 19 vaginal deliveries with elective induction (5.3%) and in two of 79 with spontaneous labor (2.5%).

CONCLUSION

Because elective induction of labor increased the cesarean rate and did not prevent shoulder dystocia, we conclude that mothers with macrosomic fetuses can safely be managed expectantly unless there is a medical indication for induction.

Diabetic fetal macrosomia: significance of disproportionate growth

Fetal hyperinsulinism in infants of diabetic mothers (IDMs) produces increased fetal growth leading to macrosomia, which may or may not be proportionate. Disproportionate macrosomia refers to excessive weight characterized by a high weight/length ratio. We tested the hypotheses that (1) macrosomia in IDMs would be characterized by a high ponderal index (defined as weight/length ratio) and (2) infants with macrosomia who have a high ponderal index would have increased neonatal morbidity--specifically, hyperbilirubinemia, hypoglycemia, polycythemia, and acidosis. We studied 170 IDMs and 510 non-IDMs matched 1:3 for gestational age, race, and year of delivery. Forty-five percent of IDMs had macrosomia compared with 8% of control infants (p = 0.001), and 19% of IDMs had disproportionate macrosomia compared with 1% of control infants (p = 0.001). The rates of hyperbilirubinemia (p = 0.02), hypoglycemia (p = 0.01), and acidosis (p = 0.01) were greatest in infants with disproportionate macrosomia and least in nonmacrosomic infants. The incidence of polycythemia was not significantly different between the groups. We suggest that disproportionate macrosomia in the IDM is associated with an increased likelihood of neonatal complications.

New Ballard Score, expanded to include extremely premature infants

The Ballard Maturational Score was refined and expanded to achieve greater accuracy and to include extremely premature neonates. To test validity, accuracy, interrater reliability, and optimal postnatal age at examination, the resulting New Ballard Score (NBS) was assessed for 578 newly born infants and the results were analyzed. Gestational ages ranged from 20 to 44 weeks and postnatal ages at examination ranged from birth to 96 hours. In 530 infants, gestational age by last menstrual period was confirmed by agreement within 2 weeks with gestational age by prenatal ultrasonography (C-GLMP). For these infants, correlation between gestational age by NBS and C-GLMP was 0.97. Mean differences between gestational age by NBS and C-GLMP were 0.32 +/- 1.58 weeks and 0.15 +/- 1.46 weeks among the extremely premature infants (less than 26 weeks) and among the total population, respectively. Correlations between the individual criteria and C-GLMP ranged from 0.72 to 0.82. Interrater reliability of NBS, as determined by correlation between raters who rated the same subgroup of infants, ws 0.95. For infants less than 26 weeks of gestational age, the greatest validity (97% within 2 weeks of C-GLMP) was seen when the examination was performed before 12 hours of postnatal age. For infants at least 26 weeks of gestational age, percentages of agreement with C-GLMP remained constant, averaging 92% for all postnatal age categories up to 96 hours. The NBS is a valid and accurate gestational assessment tool for extremely premature infants and remains valid for the entire newborn infant population.

A role for magnesium in neonatal parathyroid gland function?

Little is known of the factors regulating parathyroid function in the neonatal period. Twenty-seven term infants born after uncomplicated pregnancies, labors, and deliveries were studied to test the hypothesis that in normal newborns the amplitude of parathyroid hormone (PTH) response to decreasing serum ionized calcium (iCa) correlates with serum magnesium (Mg) concentrations. Serum iCa (ion selective electrode, Radiometer ICA 1), PTH (1-84 intact molecules, radioimmunoassay) and Mg (atomic absorption) were measured at birth (cord blood) and 24 hours of age. Repeated measures analysis of covariance showed decreasing serum iCa (p less than 0.01) and increasing serum Mg (p less than 0.01) and PTH (p less than 0.01) over time. The change in PTH over the first 24 hours was directly correlated with cord blood (r = 0.38, p less than 0.05) and 24-hr Mg concentrations (r = 0.53, p less than 0.01). We conclude that the ability of the parathyroid gland to respond to decreasing serum iCa after birth is directly related to Mg status. We speculate that neonatal hypomagnesemia may lead to a blunted PTH secretory response, thus contributing to early neonatal hypocalcemia.

Transplacental passage of insulin in pregnant women with insulin-dependent diabetes mellitus. Its role in fetal macrosomia

BACKGROUND AND METHODS

Fetal macrosomia occurs despite nearly normal maternal blood glucose levels in women with diabetes treated with insulin. We examined the hypothesis that it may be caused by insulin transferred as an insulin-antibody complex from the mother to her fetus. We adapted and validated a method based on high-performance liquid chromatography and used it to quantitate insulin in small volumes (0.5 to 1.0 ml) of cord serum from 51 infants born to mothers with insulin-dependent diabetes mellitus.

RESULTS

In mothers receiving only human insulin (n = 6), only human insulin was detected in cord serum. Of the remaining 45 infants, whose mothers received animal insulin during pregnancy, 28 (group 1) had levels of animal (bovine or porcine) insulin (mean [+/- SE], 707 +/- 163 pmol per liter) that constituted 27.4 +/- 2.5 percent of the total insulin concentration (2393 +/- 500 pmol per liter) measured in the cord serum. The cord-serum insulin concentration in the remaining 17 infants (group 2), in whom only human insulin was detected (381 +/- 56 pmol per liter), was only 15 percent of that in group 1 (P less than 0.001). There was a significant correlation between the maternal and the cord-serum concentrations of anti-insulin antibody and the concentration of animal insulin in the baby (r = 0.77, P less than 0.01, and r = 0.76, P less than 0.001, respectively), suggesting that the animal insulin was transferred as an insulin-antibody complex. In group 1 the mean concentration of animal insulin in cord serum was higher in the 12 infants with macrosomia than in the 16 infants without the condition (1113 +/- 321 vs. 402 +/- 110 pmol per liter; P less than 0.05), and the concentration of animal insulin in cord serum correlated with birth weight (r = 0.39, P less than 0.05). The maternal glycosylated hemoglobin values and the incidence of respiratory distress syndrome were similar in groups 1 and 2.

CONCLUSIONS

Considerable amounts of antibody-bound insulin are transferred from mother to fetus during pregnancy in some women with insulin-dependent diabetes mellitus; the extent of transfer correlates with the maternal concentration of anti-insulin antibody. The correlation between macrosomia and the concentrations of animal insulin in cord serum indicates that the transferred insulin has biologic activity and suggests that the formation of antibody to insulin in the mother is a determinant of fetal outcome independent of maternal blood glucose levels.

Biphasic intrauterine growth in insulin-dependent diabetic pregnancies

Early fetal growth delay (7-14 weeks of gestation) has been reported in insulin-dependent diabetic (IDD) pregnancies and in several animal models. Macrosomia is a classic feature of the infant of the IDD mother. We hypothesized therefore that a biphasic pattern of fetal growth exists in IDD pregnancies. We compared fetal growth measurements [biparietal diameter (BPD) and abdominal circumference (AC)] obtained sonographically from 106 IDD pregnancies (Class B-RT) to similar data obtained from 117 normal, nondiabetic patients. The goals for diabetic glycemic control were: fasting blood sugar less than or equal to 100 mg/dl and postprandial blood sugar less than 140 mg/dl. From one to five ultrasonographic measurements were performed at varying gestational ages in all study patients. For data analysis, one examination from each pregnancy was randomly selected by computer. Gestational age (GA) was calculated from last menstrual period and corroborated by infant physical examination (Ballard score) at birth. BPD growth pattern was biphasic in the diabetic group, described by a cubic equation: BPD = 4.99 - 0.567GA + 0.037(GA)2 - 0.0005(GA)3, R2 = 0.935. Such a biphasic pattern did not exist in the control population [BPD = -3.0323 + 0.473(gestation) - (-0.0040)(gestation)2, R2 = 0.9173]. Early growth delay was greater in fetuses that subsequently developed macrosomia (p less than 0.01). Similar results were found for AC measurements. We conclude that fetal growth delay occurs in the first half of the IDD pregnancy, followed by a phase of increased growth. The mechanism of the early growth delay is unclear. We speculate that early growth delay may be due to a "toxic" effect of glucose or other metabolite; and subsequent increased growth relates to fetal hyperinsulinism which develops from weeks 15 to 20 of gestation.

Atrial natriuretic factor during the perinatal period: equal depletion in both atria

Data in the literature concerning atrial natriuretic factor (ANF) physiology in the fetus and newborn, although limited, suggest significant activity during the perinatal period. To characterize further ANF physiology during this time, we documented immunoreactive ANF (IR-ANF) concentrations in the right and left atria before and immediately after birth as well as in the hearts of immature and adult rats. There was a significant decrease in the concentration of IR-ANF in both right and left atria on the d before birth that persisted for the first 48 h of life [d 20 fetal right 570 (106, 90), left 580 (86, 75); d 21 fetal right 270 (70, 55), left 214 (117, 75); 1 d right 206 (39, 33), left 229 (41, 35); 2-d right 352 (35, 32), left 237 (26, 23) [geometric mean (upper SE, lower SE) in ng ANF/mg protein]. Repletion of ANF stores began in the right atrium on d 2 of life and in the left atrium between d 2 and 5. The highest levels of IR-ANF were observed at d 15 [d 5 right 1439 (53,51), left 1547 (83,79); d 15 right 2034 (90,86), left 1943 (108, 102); adult right 1380 (119, 109), left 963 (118, 105)]. In contrast to normal adult animals, factors mediating the observed change affect both atria equally during the perinatal period. The concentration of IR-ANF in the right and left atrium of the fetal, newborn, and immature animals was equal. These data document significant alterations in intraatrial IR-ANF concentrations in the perinatal period.(ABSTRACT TRUNCATED AT 250 WORDS)

Prediction of coronary artery disease in a population of insulin-requiring diabetic patients: results of an 8-year follow-up study

To identify predictors of clinical coronary artery disease, 110 insulin-requiring diabetic patients with no symptoms suggestive of cardiac disease and with a normal resting ECG underwent metabolic and noninvasive cardiovascular screening including a history and physical examination, exercise ECG, M-mode echocardiography, and chemical laboratory testing. During a median follow-up interval of 100 months, 14 of these patients had clinical evidence of coronary artery disease consisting of acute myocardial infarction, sudden cardiac death, or anginal chest pain with angiographic documentation of occlusive coronary artery disease. Baseline variables that were univariately predictive of subsequent clinical coronary disease included age, peak treadmill heart rate, and retinal neovascularization. According to multivariate analysis the peak treadmill heart rate was the single most important predictor of subsequent development of clinical coronary disease. A treadmill ECG result that was either abnormal or inconclusive because of failure to achieve 90% of predicted maximal heart rate identified each patient in whom clinical coronary artery disease developed within 50 months after entry testing. Thus the entry treadmill ECG provided prognostic information not available from the history and physical examination results, but little further prognostic information was provided after the first 50 months of follow-up, suggesting the need for serial testing.