Marian G. Ewell

Trial of calcium to prevent preeclampsia

Background Previous trials have suggested that calcium supplementation during pregnancy may reduce the risk of preeclampsia. However, differences in study design and a low dietary calcium intake in the populations studied limit acceptance of the data. Methods We randomly assigned 4589 healthy nulliparous women who were 13 to 21 weeks pregnant to receive daily treatment with either 2 g of elemental calcium or placebo for the remainder of their pregnancies. Surveillance for preeclampsia was conducted by personnel unaware of treatment-group assignments, using standardized measurements of blood pressure and urinary protein excretion at uniformly scheduled prenatal visits, protocols for monitoring these measurements during the hospitalization for delivery, and reviews of medical records of unscheduled outpatient visits and all hospitalizations. Results Calcium supplementation did not significantly reduce the incidence or severity of preeclampsia or delay its onset. Preeclampsia occurred in 158 of the 2295 wome...

Efficacy Results of a Trial of a Herpes Simplex Vaccine

BACKGROUND Two previous studies of a herpes simplex virus type 2 (HSV-2) subunit vaccine containing glycoprotein D in HSV-discordant couples revealed 73% and 74% efficacy against genital disease in women who were negative for both HSV type 1 (HSV-1) and HSV-2 antibodies. Efficacy was not observed in men or HSV-1 seropositive women. METHODS We conducted a randomized, double-blind efficacy field trial involving 8323 women 18 to 30 years of age who were negative for antibodies to HSV-1 and HSV-2. At months 0, 1, and 6, some subjects received the investigational vaccine, consisting of 20 μg of glycoprotein D from HSV-2 with alum and 3-O-deacylated monophosphoryl lipid A as an adjuvant; control subjects received the hepatitis A vaccine, at a dose of 720 enzyme-linked immunosorbent assay (ELISA) units. The primary end point was occurrence of genital herpes disease due to either HSV-1 or HSV-2 from month 2 (1 month after dose 2) through month 20. RESULTS The HSV vaccine was associated with an increased risk of local reactions as compared with the control vaccine, and it elicited ELISA and neutralizing antibodies to HSV-2. Overall, the vaccine was not efficacious; vaccine efficacy was 20% (95% confidence interval [CI], -29 to 50) against genital herpes disease. However, efficacy against HSV-1 genital disease was 58% (95% CI, 12 to 80). Vaccine efficacy against HSV-1 infection (with or without disease) was 35% (95% CI, 13 to 52), but efficacy against HSV-2 infection was not observed (-8%; 95% CI, -59 to 26). CONCLUSIONS In a study population that was representative of the general population of HSV-1- and HSV-2-seronegative women, the investigational vaccine was effective in preventing HSV-1 genital disease and infection but not in preventing HSV-2 disease or infection. (Funded by the National Institute of Allergy and Infectious Diseases and GlaxoSmithKline; ClinicalTrials.gov number, NCT00057330.).

The relationship between abnormal glucose tolerance and hypertensive disorders of pregnancy in healthy nulliparous women

OBJECTIVE The studys aim was to determine whether healthy nulliparous women with abnormal glucose tolerance during pregnancy are at increased risk for development of pregnancy-associated hypertension or preeclampsia. STUDY DESIGN A series of 4589 healthy nulliparous women from 5 university centers were evaluated prospectively to determine whether calcium supplementation would prevent preeclampsia. Pregnancy-associated hypertension was a diastolic blood pressure > or = 90 mm Hg on 2 occasions 4 hours to 1 week apart. Pregnancy-associated proteinuria was proteinuria > or = 1+ by dipstick testing on 2 occasions 4 hours to 1 week apart, proteinuria > or = 300 mg/24 h, a protein to creatinine ratio of > or = 0.35, or a single dipstick measurement of > or = 2+. Preeclampsia was defined as pregnancy-associated hypertension and pregnancy-associated proteinuria documented within 7 days of each other. Normal glucose tolerance was a plasma glucose level < 140 mg/dL 1 hour after a 50-g oral glucose challenge. Abnormal glucose tolerance was a plasma glucose level > or = 140 mg/dL 1 hour after a 50-g oral glucose challenge followed by a 3-hour 100-g oral glucose tolerance test yielding < 2 abnormal values. Gestational diabetes mellitus was a plasma glucose level > or = 200 mg/dL 1 hour after a 50-g oral glucose challenge in the absence of an oral glucose tolerance test or > or = 2 abnormal plasma glucose values in a 3-hour 100-g oral glucose tolerance test (> or = 105 mg/dL fasting, > or = 190 mg/dL at 1 hour, > or = 165 mg/dL at 2 hours, or > or = 145 mg/dL at 3 hours). For purposes of this study women with preeclampsia were excluded from the category of pregnancy-associated hypertension. RESULTS Calcium supplementation did not prevent pregnancy-associated hypertension or preeclampsia. Of 3689 women with complete glucose testing data, 227 (6%) had abnormal glucose tolerance and 81 (2%) had gestational diabetes mellitus. Compared with women with normal glucose tolerance, women with abnormal glucose tolerance were significantly older, had greater body mass index, and were more likely to be white non-Hispanic, to smoke, and to have private medical insurance. Among women with gestational diabetes mellitus, after adjustment for clinical center the relative risks of preeclampsia and of all hypertensive disorders were increased (relative risk 1.67, 95% confidence interval 0.92-3.05, and relative risk 1.54, 95% confidence interval 1.28-2.11, respectively). Risk ratios were not substantially reduced after further adjustment for race and body mass index (odds ratios 1.41 and 1.48, respectively). Even within the normal range, multivariate analysis demonstrated that the level of plasma glucose 1 hour after a 50-g oral glucose challenge was an important predictor of preeclampsia. CONCLUSION Even within the normal range, the level of plasma glucose 1 hour after a 50-g oral glucose challenge was positively correlated with the likelihood of preeclampsia. Women with gestational diabetes mellitus were at increased risk for hypertensive disorders during pregnancy after adjustment for clinical center, race, and body mass index, although the increase was not statistically significant. These findings suggest that insulin resistance may play a role in the pathogenesis of the hypertensive disorders of pregnancy.

Trial of calcium for preeclampsia prevention (CPEP): Rationale, design, and methods

The results of ten clinical trials suggest that supplemental calcium may prevent preeclampsia. However, methodologic problems and differences in study design limit the acceptance of the results and their relevance to other patient populations. Many of the trials were conducted in countries where, unlike the United States, the usual daily diet contained little calcium. Moreover, none of the trials has reported the outcome of systematic surveillance for urolithiasis, a potential complication of calcium supplementation. In response to the need for a thorough evaluation of the effects of calcium supplementation for the prevention of preeclampsia in the United States, the trial of Calcium for Preeclampsia Prevention (CPEP) was undertaken at five university medical centers. Healthy nulliparous patients were randomly assigned to receive either 2 g supplemental calcium daily (n = 2295) or placebo (n = 2294) in a double-blind study. Study tablets were administered beginning from 13 to 21 completed weeks of gestation and continued until the termination of pregnancy. CPEP employed detailed diagnostic criteria, standardized techniques of measurement, and systematic surveillance for the major study endpoints and for urolithiasis. The nutrient intake of each patient was assessed at randomization and at 32-33 weeks gestation. This report describes the study rationale, design, and methods.

Correlate of Immune Protection Against HSV-1 Genital Disease in Vaccinated Women

BACKGROUND Previously we conducted a double-blind controlled, randomized efficacy field trial of gD-2 HSV vaccine adjuvanted with ASO4 in 8323 women. Subjects had been previously selected to be seronegative for HSV-1 and HSV-2. We found that vaccine was 82% protective against HSV-1 genital disease, but offered no significant protection against HSV-2 genital disease. METHODS To better understand the results of the efficacy study, post-vaccination anti-gD-2 antibody concentrations from all HSV infected subjects and matched uninfected controls were measured. Three models were used to determine whether thes responses correlated with protection against HSV infection or disease. Similarly, cellular immune responses from a subset of subjects and matched controls were evaluated for a correlation with HSV protection. RESULTS Antibodies to gD-2 correlated with protection against HSV-1 infection with higher antibody concentration associated with higher efficacy. Cellular immune responses to gD-2 did not correlate with protection. CONCLUSIONS The protection against HSV-1 infection observed in the Herpevac Trial for Women was associated with antibodies directed against the vaccine. Clinical Trials Registration NCT00057330.

Twenty‐four‐hour urine insulin as a measure of hyperinsulinaemia/insulin resistance before onset of pre‐eclampsia and gestational hypertension

Objective  To evaluate levels of 24‐hour urine insulin excretion before the onset of pre‐eclampsia and gestational hypertension.

HSV-1 and HSV-2 seroprevalence in the united states among asymptomatic women unaware of any herpes simplex virus infection (Herpevac Trial for Women).

Objectives Recent evidence suggests that the epidemiology of herpes simplex viruses (HSVs) is changing because fewer HSV-1 infections are acquired in childhood and increased sexual transmission of HSV-1 is reported. The objective of the study was to assess the seroprevalence of type-specific antibodies to HSV-1 and HSV-2 in the United States. Methods We used the Western blot antibody screening data from a large phase III vaccine efficacy trial (Herpevac Trial for Women) to assess the seroprevalence of type-specific antibodies to HSV-1 and HSV-2 in the United States. Results The antibody status of 29,022 women (>31,000 women interviewed and then had their blood drawn for the HSV testing [29,022 women]) between the ages of 18 and 30 years in the United States revealed that increasing age was associated with increasing seroprevalence to HSV. Overall, in asymptomatic women unaware of any HSV infection, HSV-1/-2 status was positive/negative in 45%, negative/positive in 5%, positive/positive in 7%, negative/negative in 38%, and indeterminate in 5%. HSV-1 infections were more common in Hispanic and non-Hispanic black women and in the US northeast and in individuals living in urban areas. HSV-2 was more common in non-Hispanic black women, the US south, and in urban areas. Conclusions Seronegative status for both HSV-1 and HSV-2 was the second most common finding after positive antibody to HSV-1 but negative antibody to HSV-2. Despite recent changes in genital herpes epidemiology, most women acquired HSV-1 but not HSV-2 infections before 18 years of age. Among participants screened for study participation and who were unaware of any HSV infection, progressively higher prevalence of the HSV-1 or HSV-2 antibody was observed in older subjects. Many women who test positive for HSV-1 and/or HSV-2 are unaware of their status.

A Phase II Randomized, Control Trial of Group B Streptococcus (GBS) Type III Capsular Polysaccharide -Tetanus Toxoid (GBS III-TT) Vaccine to Prevent Vaginal Colonization with GBS III

BACKGROUND Group B Streptococcus (GBS) frequently colonizes pregnant women and can cause sepsis and meningitis in young infants. If colonization was prevented through maternal immunization, a reduction in perinatal GBS disease might be possible. A GBS type III capsular polysaccharide (CPS)-tetanus toxoid conjugate (III-TT) vaccine was evaluated for safety and efficacy in preventing acquisition of GBS colonization. METHODS Healthy, nonpregnant women aged 18-40 years and screened to be GBS III vaginal and rectal culture negative were randomized to receive III-TT conjugate or tetanus diphtheria toxoid vaccine in a multicenter, observer-blinded trial. GBS vaginal and rectal cultures and blood were obtained bimonthly over 18 months. Serum concentrations of GBS III CPS-specific antibodies were determined using enzyme-linked immunosorbent assay. RESULTS Among 1525 women screened, 650 were eligible for the intent-to-treat analysis. For time to first acquisition of vaginal GBS III, vaccine efficacy was 36% (95% confidence interval [CI], 1%-58%; P = .044), and for first rectal acquisition efficacy was 43% (95% CI, 11% to 63%; P = .014). Two months post-immunization, geometric mean concentrations of serum GBS type III CPS-specific immunoglobulin G were 12.6 µg/mL (95% CI, 9.95 to 15.81) in GBS III-TT recipients, representing a 4-fold increase from baseline in 95% of women, which persisted. Both vaccines were well tolerated. CONCLUSIONS GBS CPS III-TT conjugate vaccine significantly delayed acquisition of vaginal and rectal GBS III colonization. In addition to its use for maternal immunization to passively protect infants with maternally derived antibodies, a multivalent vaccine might also serve to reduce fetal and neonatal exposure to GBS. CLINICAL TRIALS REGISTRATION NCT00128219.