Vedolizumab and Ustekinumab Levels in Pregnant Women With Inflammatory Bowel Disease and Infants Exposed In Utero

BACKGROUND & AIMS

Vedolizumab and ustekinumab pharmacokinetics in pregnancy and the infant after in utero exposure remain incompletely defined. We aim to define the antenatal stability of ustekinumab and vedolizumab levels and the time at which infant drug levels become undetectable.

METHODS

This multicenter prospective observational cohort study recruited pregnant or preconception women with inflammatory bowel disease receiving vedolizumab or ustekinumab. Trough drug levels, clinical data, and biochemical data were documented preconception, during each trimester of pregnancy, and postpartum. Maternal and cord blood drug levels were measured at delivery and in infants until undetectable. Infant outcomes were assessed until 2 years of age.

RESULTS

A total of 102 participants (vedolizumab, n = 58) were included. The majority of mothers were, and remained, in clinical and biochemical remission. Maternal vedolizumab levels decreased over the course of pregnancy in association with increasing weight, rather than increasing gestation. Maternal ustekinumab levels remained stable. The median time to drug becoming undetectable in the infant was shorter for vedolizumab (11 wk; range, 5-19 wk; n = 32) than ustekinumab (14 wk; range, 9-36 wk; n = 17) and correlated positively with infant delivery level. Thirty-two of 41 (88%) and 17 of 30 (67%) vedolizumab- and ustekinumab-exposed infants had undetectable drug levels by 15 weeks of age, respectively. Pregnancy and infant outcomes were favorable. Twenty infants with undetectable drug levels received the rotavirus vaccine, with no adverse reactions reported.

CONCLUSIONS

Maternal vedolizumab levels decreased, whereas ustekinumab levels remained stable over the course of pregnancy. Most vedolizumab- and approximately half of ustekinumab-exposed infants had undetectable drug levels by 15 weeks of age. No concerning maternal or infant safety signals were identified.

Thiopurine metabolite shunting in late pregnancy increases the risk of intrahepatic cholestasis of pregnancy in women with inflammatory bowel disease, and can be managed with split-dosing

BACKGROUND AND AIMS

The risk of intrahepatic cholestasis of pregnancy (ICP) is increased in thiopurine exposed pregnancies. Thiopurine 'shunting', with a 6-methylmecrcaptopurine (MMP) to 6-thioguanine (TGN) ratio of >11, progresses over pregnancy, and may promote ICP development. We aimed to explore the association between thiopurine exposure and ICP, including the hypothesized impact of thiopurine shunting, and identify risk minimization strategies.

METHODS

This prospective multi-centre cohort study compared thiopurine and biologic monotherapy exposed pregnant participants. Disease activity and obstetric outcome data, thiopurine metabolites, bile acids and transaminases were obtained preconception, in each trimester, at delivery, and post-partum. Thiopurine dose management was at the discretion of the treating physician.

RESULTS

131 thiopurine and 147 biologic monotherapy exposed pregnancies were included. MMP/TGN ratio increased from preconception to third trimester (p<0.01), with approximately 25% of participants shunting in pregnancy. Second trimester split-dosing led to a decrease in the median MMP/TGN ratio from 18 (IQR 6-57) to 3 (IQR 2-3.5) at delivery (p=0.04). The risk of ICP was increased in thiopurine exposed pregnancies (6.7% (7/105) vs 0% (0/112), p<0.001), with all ICP cases occurring in the setting of antenatal thiopurine shunting. Thiopurine dose increases (RR 8.10 [95% CI 1.88-34.85] p=0.005) and shunting in third trimester (6.20 [1.21-30.73] p=0.028) and at delivery (14.18 [1.62-123.9] p=0.016) were associated with an increased risk of ICP.

CONCLUSIONS

Thiopurine exposure is associated with an increased risk of ICP, particularly following dose increases antenatally and with shunting in late pregnancy. The latter may be effectively managed with split dosing, although further studies are warranted.

Thrombocytosis and Transaminitis in Infants Born to Women With Inflammatory Bowel Disease Is Associated With Exposure to Maternal Inflammation In Utero

BACKGROUND

Despite reassuring clinical safety data, thrombocytosis, anemia, lymphopenia, and liver function derangements have been observed in infants born to women with inflammatory bowel disease (IBD) treated with thiopurines and biologics. We aimed to define the prevalence, course, associations, and clinical impact of hematological and biochemical abnormalities in such infants.

METHODS

This multicenter prospective cohort study assessed clinical, hematologic, and biochemical outcomes of infants exposed to thiopurines or biologics in utero for management of maternal IBD. Liver transaminases, full blood examination, and infant thiopurine metabolites (where exposed) were taken at delivery and 6 weeks of age. Abnormal results were repeated until normalization. Infants were followed clinically by a pediatric gastroenterologist up to 2 years of age.

RESULTS

A total of 130 infants were included. Thrombocytosis and elevated alanine transaminase (ALT) were seen in over half of infants up to 6 months of age with no significant clinical impact. Elevated ALT was associated with increasing maternal C-reactive protein in second trimester, while thrombocytosis was associated with increasing maternal C-reactive protein and fecal calprotectin in third trimester. Preceding infection and vaccination were associated with an increased risk of elevated alkaline phosphatase at 3 months. In those exposed to thiopurines, increasing maternal 6-methylmercaptopurine at delivery was associated with increased ALT to 6 months.

CONCLUSIONS

Infants born to women with IBD commonly developed thrombocytosis, elevated alkaline phosphatase, and elevated ALT. These findings were associated with exposure to maternal inflammation, elevated 6-methylmercaptopurine at delivery, and infant vaccinations and infections, and had minimal clinical consequence.

Ustekinumab levels in pregnant women with inflammatory bowel disease and infants exposed in utero

BACKGROUND

Ustekinumab is increasingly used in pregnant women with inflammatory bowel disease (IBD). Existing safety data are reassuring, but the stability of ustekinumab levels in pregnancy, degree of transfer to the infant and time to infant clearance are unknown.

METHODS

In this prospective observational study, ustekinumab-exposed women with IBD had trough levels measured in each trimester of pregnancy and at delivery. Infant ustekinumab levels were measured at delivery and ongoing until clearance was achieved. Trough ustekinumab level stability in individuals across pregnancy was compared by Skillings-Mack test. Spearman coefficients were used to correlate maternal and infant delivery levels, and median time to infant ustekinumab clearance was defined.

RESULTS

19 pregnant women receiving ustekinumab were included. There was no difference in ustekinumab levels across pregnancy in those with two or more representative trough levels (P = 0.83, n = 11). Infant delivery ustekinumab levels were higher than maternal levels, with a median infant:maternal ratio of 1.79 (IQR 1.26-3.1). There was a positive correlation between maternal and infant delivery ustekinumab levels (r = 0.75, P = 0.001) and an inverse correlation between the number of days from final antenatal dose and delivery infant ustekinumab level (r = -0.65, P = 0.006). Median time of infant ustekinumab clearance was 9 (range 6-19) weeks (n = 9).

CONCLUSION

Ustekinumab drug levels appear stable in pregnancy, with a delivery infant:maternal ratio similar to that of anti-TNFs. Infant ustekinumab clearance was complete by 20 weeks post-partum, however, infants exposed in utero should avoid live vaccination before 12 months of age until further clearance data are obtained.

Evaluation and management of rectal bleeding in pregnancy

Rectal bleeding occurs in about 40% of pregnant women, and is predominantly attributed to benign perianal pathology (haemorrhoids or anal fissures). More sinister causes of rectal bleeding may be heralded by key red flag clinical and biochemical features. These features should be evaluated in all women with rectal bleeding. Imaging investigations or flexible sigmoidoscopy may be warranted. The latter can be performed safely by experienced operators in pregnant women. Women with evidence of haemodynamic compromise, elevated inflammatory markers, significant anaemia, signs of intestinal obstruction or compromise to the fetus should be evaluated urgently. Providers must be mindful of the changes in normal ranges for common haematological and biochemical parameters in pregnancy compared with the non-pregnant state. Faecal calprotectin is an established tool for identification of intestinal inflammation and is valid in pregnancy. An elevated faecal calprotectin level (≥ 50 µg/g) signifies a need for further diagnostic evaluation. Inflammatory bowel disease may present initially, or with worsening disease activity, in pregnancy. Expedient diagnosis with the use of faecal calprotectin, sigmoidoscopy with or without intestinal ultrasound, exclusion of alternative or compounding infective aetiologies, and institution of appropriate therapy are critical. Medical therapies for management of inflammatory bowel disease can be safely instituted in pregnancy. Colorectal cancer incidence is increasing in younger age groups, but fortunately remains rare. When diagnosed in pregnancy, colorectal cancer can be successfully and safely managed with a collaborative multidisciplinary team approach. Early diagnosis is key to optimising outcomes.

Altered bowel habit and rectal bleeding in pregnancy: the importance of recognising undiagnosed inflammatory bowel disease

Worsening of disease activity during pregnancy in patients with known inflammatory bowel disease, especially ulcerative colitis (UC), is well recognised, but the diagnosis of new-onset or previously undiagnosed UC in pregnancy has been inadequately studied to date. Recognition of gastrointestinal symptoms in pregnancy as potentially indicating UC is of paramount importance, as this allows appropriate investigation and instigation of therapies to optimise maternal and foetal outcomes. Here, we report three cases of women with gastrointestinal symptoms in pregnancy with disparate outcomes.

Review article: investigation and management of internal fistulae in Crohn's disease

BACKGROUND

Crohn's disease is an inflammatory, penetrating intestinal disease associated with fistula formation. Fistulae in Crohn's disease can be classified into external and internal fistulae. Internal fistulae form between the gastrointestinal tract and another internal organ and include enteroenteric, enterocolic, enterovesical and rectovaginal fistulae. They are associated with significant morbidity and a decreased quality of life.

AIM

To review the classification, diagnosis, medical and surgical management of internal fistulae in Crohn's disease, and propose a treatment algorithm.

METHODS

A literature review on internal fistulae in Crohn's disease in the adult population was undertaken, synthesised and summarised.

RESULTS

Internal fistulae occur in up to 15% of patients with Crohn's disease. Multi-modal assessment including a combination of endoscopy and cross-sectional imaging, usually magnetic resonance, is required to diagnose fistulae and determine extent of disease. Determining optimal treatment strategies for these complex fistulae remains a challenge due to limited and generally low-quality data. Most studies to date have focussed on luminal disease, with (usually post hoc) outcomes more often reported for external fistulae, particularly perianal fistulae, than internal fistulae. Anti-tumour necrosis factor therapies have emerged as the mainstay of medical therapy, with particularly promising data for enterovesical fistulae, but many patients will still require surgical intervention. The indications and optimal timing of surgery vs medical therapy remains uncertain; thus multi-disciplinary input when making such decisions is important.

CONCLUSIONS

Internal fistulae result in significantly increased morbidity in Crohn's disease, and further studies to determine optimal multi-modality management strategies incorporating medical and surgical therapy are required.

Practical management of inflammatory bowel disease patients during the COVID-19 pandemic: expert commentary from the Gastroenterological Society of Australia Inflammatory Bowel Disease faculty

The COVID‐19 pandemic, caused by the novel coronavirus SARS‐CoV‐2, has emerged as a public health emergency and challenged healthcare systems globally. In a minority of patients, SARS‐CoV‐2 manifests with a severe acute respiratory illness and currently there are insufficient data regarding the virulence of COVID‐19 in inflammatory bowel disease patients taking immunosuppressive therapy. This review aims to summarise the current literature and provide guidance on the management of inflammatory bowel disease (IBD) patients in the context of the COVID‐19 pandemic in the Australasian setting.

Vitamin B6 catabolism and lung cancer risk: results from the Lung Cancer Cohort Consortium (LC3)

BACKGROUND

Increased vitamin B6 catabolism related to inflammation, as measured by the PAr index (the ratio of 4-pyridoxic acid over the sum of pyridoxal and pyridoxal-5'-phosphate), has been positively associated with lung cancer risk in two prospective European studies. However, the extent to which this association translates to more diverse populations is not known.

MATERIALS AND METHODS

For this study, we included 5323 incident lung cancer cases and 5323 controls individually matched by age, sex, and smoking status within each of 20 prospective cohorts from the Lung Cancer Cohort Consortium. Cohort-specific odds ratios (ORs) and 95% confidence intervals (CIs) for the association between PAr and lung cancer risk were calculated using conditional logistic regression and pooled using random-effects models.

RESULTS

PAr was positively associated with lung cancer risk in a dose-response fashion. Comparing the fourth versus first quartiles of PAr resulted in an OR of 1.38 (95% CI: 1.19-1.59) for overall lung cancer risk. The association between PAr and lung cancer risk was most prominent in former smokers (OR: 1.69, 95% CI: 1.36-2.10), men (OR: 1.60, 95% CI: 1.28-2.00), and for cancers diagnosed within 3 years of blood draw (OR: 1.73, 95% CI: 1.34-2.23).

CONCLUSION

Based on pre-diagnostic data from 20 cohorts across 4 continents, this study confirms that increased vitamin B6 catabolism related to inflammation and immune activation is associated with a higher risk of developing lung cancer. Moreover, PAr may be a pre-diagnostic marker of lung cancer rather than a causal factor.

No association between circulating concentrations of vitamin D and risk of lung cancer: an analysis in 20 prospective studies in the Lung Cancer Cohort Consortium (LC3)

Background

There is observational evidence suggesting that high vitamin D concentrations may protect against lung cancer. To investigate this hypothesis in detail, we measured circulating vitamin D concentrations in prediagnostic blood from 20 cohorts participating in the Lung Cancer Cohort Consortium (LC3).

Patients and methods

The study included 5313 lung cancer cases and 5313 controls. Blood samples for the cases were collected, on average, 5 years before lung cancer diagnosis. Controls were individually matched to the cases by cohort, sex, age, race/ethnicity, date of blood collection, and smoking status in five categories. Liquid chromatography coupled with tandem mass spectrometry was used to separately analyze 25-hydroxyvitamin D2 [25(OH)D2] and 25-hydroxyvitamin D3 [25(OH)D3] and their concentrations were combined to give an overall measure of 25(OH)D. We used conditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for 25(OH)D as both continuous and categorical variables.

Results

Overall, no apparent association between 25(OH)D and risk of lung cancer was observed (multivariable adjusted OR for a doubling in concentration: 0.98, 95% CI: 0.91, 1.06). Similarly, we found no clear evidence of interaction by cohort, sex, age, smoking status, or histology.

Conclusion

This study did not support an association between vitamin D concentrations and lung cancer risk.

Breast cancer after stopping estrogen plus progestin in postmenopausal women in the women's health initiative

Abstract #64

Background&#x2028; Following the Women's Health Initiative (WHI) estrogen plus progestin (E+P) trial report (JAMA 2002;288:321), menopausal hormone therapy use decreased dramatically in the United States. Subsequently, breast cancer incidence also dropped substantially, suggesting possible causality (NEJM 2007;16:1680); however, the etiology remains controversial.&#x2028; Methods&#x2028; To define effects of stopping E+P on breast cancer incidence more precisely, additional analyses were conducted in the WHI randomized trial of daily conjugated equine estrogens (CEE, 0.625 mg) plus medroxyprogesterone acetate (MPA, 2.5 mg) versus placebo. Furthermore, temporal trends for breast cancer diagnoses in the WHI observational study cohort were examined. Breast cancer risk factors, mammography utilization and calendar time-specific breast cancer incidence were assessed relative to E+P use.&#x2028; Results: The time-specific linear hazard ratio (HR) curves examining E+P influence on breast cancer in the E+P clinical trial (CT), and in the observational study (OS, the later adjusted for E+P use during follow-up) are attached.&#x2028; &#x2028; &#x2028; &#x2028; In the CT, breast cancer incidence, initially lower in the E+P group, increased with longer duration use but decreased postintervention despite closely comparable mammogram frequency between randomization groups. In the OS, breast cancer incidence was about two-fold higher in E+P users vs non-users (likely reflecting longer duration exposure) but decreased rapidly following year-to-year reductions in E+P use, while differences in mammogram frequency between E+P users and non-users were unchanged.&#x2028; Conclusion: These findings suggest that cessation of E+P use is associated with a rapid reduction in breast cancer incidence which is not explained by mammography utilization change and support the hypothesis that the recent reduction in breast cancer incidence seen in certain age groups is predominantly related to a decrease in combined menopausal therapy use.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 64.

Assessment of neuroimaging techniques as biomarkers of the progression of Parkinson's disease

A major goal of research in Parkinson's disease (PD) has been the development of treatments to slow the progressive degeneration of the nigrostriatal dopaminergic system and to reduce the functional decline of patients. Because of the uncertainty in the ability of the clinical evaluation to reflect the status of the nigrostriatal dopaminergic system once dopaminergic therapy has commenced, investigators in PD have sought to develop alternative measures of disease. One approach, which has been extensively explored, is neuroimaging with radiotracers that interact with processes central to dopaminergic neurotransmission in the nigrostriatal dopaminergic axons-conversion of levodopa to dopamine through aromatic amino acid decarboxylase (AADC), [(18)F]fluorodopa PET, storage of dopamine in synaptic vesicles via the vesicular monoamine transporter 2 (VMAT2), (+)-[(11)C]dihydrotetrabenazine PET, and reuptake of dopamine into axons via the dopamine transporter (DAT), [(123)I]beta-CIT SPECT, and a number of other PET and SPECT ligands. During the 54(th) Annual Meeting of the American Academy of Neurology, a group of investigators active in the fields of biomakers, neuroimaging, and neuroprotection met to review the three techniques mentioned above. Prior to the meeting, the participants developed consensus on a set of 10 criteria for a neuroimaging technique to be considered adequate as a biomarker for progression of PD and levels at which the available data for each technique indicate that the criterion was met. The criteria and each of the three imaging techniques mentioned above were reviewed, and the results of that meeting are presented.

Considerations in the evaluation of surrogate endpoints in clinical trials. summary of a National Institutes of Health workshop

We report on recommendations from a National Institutes of Health Workshop on methods for evaluating the use of surrogate endpoints in clinical trials, which was attended by experts in biostatistics and clinical trials from a broad array of disease areas. Recent advances in biosciences and technology have increased the ability to understand, measure, and model biological mechanisms; appropriate application of these advances in clinical research settings requires collaboration of quantitative and laboratory scientists. Biomarkers, new examples of which arise rapidly from new technologies, are used frequently in such areas as early detection of disease and identification of patients most likely to benefit from new therapies. There is also scientific interest in exploring whether, and under what conditions, biomarkers may substitute for clinical endpoints of phase III trials, although workshop participants agreed that these considerations apply primarily to situations where trials using clinical endpoints are not feasible. Evaluating candidate biomarkers in the exploratory phases of drug development and investigating surrogate endpoints in confirmatory trials require the establishment of a statistical and inferential framework. As a first step, participants reviewed methods for investigating the degree to which biomarkers can explain or predict the effect of treatments on clinical endpoints measured in clinical trials. They also suggested new approaches appropriate in settings where biomarkers reflect only indirectly the important processes on the causal path to clinical disease and where biomarker measurement errors are of concern. Participants emphasized the need for further research on development of such models, whether they are empirical in nature or attempt to describe mechanisms in mathematical terms. Of special interest were meta-analytic models for combining information from multiple studies involving interventions for the same condition. Recommendations also included considerations for design and conduct of trials and for assemblage of databases needed for such research. Finally, there was a strong recommendation for increased training of quantitative scientists in biologic research as well as in statistical methods and modeling to ensure that there will be an adequate workforce to meet future research needs.

Statistical modeling of large microarray data sets to identify stimulus-response profiles

A statistical modeling approach is proposed for use in searching large microarray data sets for genes that have a transcriptional response to a stimulus. The approach is unrestricted with respect to the timing, magnitude or duration of the response, or the overall abundance of the transcript. The statistical model makes an accommodation for systematic heterogeneity in expression levels. Corresponding data analyses provide gene-specific information, and the approach provides a means for evaluating the statistical significance of such information. To illustrate this strategy we have derived a model to depict the profile expected for a periodically transcribed gene and used it to look for budding yeast transcripts that adhere to this profile. Using objective criteria, this method identifies 81% of the known periodic transcripts and 1,088 genes, which show significant periodicity in at least one of the three data sets analyzed. However, only one-quarter of these genes show significant oscillations in at least two data sets and can be classified as periodic with high confidence. The method provides estimates of the mean activation and deactivation times, induced and basal expression levels, and statistical measures of the precision of these estimates for each periodic transcript.

Integrated designs for gene discovery and characterization

Recent advances, including near completion of the human genome map, ever improving high-throughput technologies, and successes in discovering chronic disease-related genes, have stimulated the further development of genetic epidemiology. The primary mission of genetic epidemiology is to discover and characterize genes, whether independent of or interactive with environmental factors, that cause human diseases. To accomplish such a mission, genetic epidemiology needs to integrate both genetic and epidemiologic approaches. One of the challenges facing such an integrated approach is the identification of study designs that are efficient for both gene discovery and characterization. Because designs for gene discovery alone and designs for gene characterization alone have been elaborated in the other two panels, the focus of this paper is to describe those designs that may be useful for discovery and characterization jointly, including case-family and case-control-family designs. Examples of integrated designs are described, and studies of breast cancer conducted at the Fred Hutchinson Cancer Research Center are used for illustration. Finally, related analytic issues are also discussed.

Pyoderma gangrenosum with secondary pyarthrosis following propylthiouracil

The association of pyoderma gangrenosum and arthritic symptoms is well documented. We present a rarely reported variant of this in a 44-year-old woman with pyoderma gangrenosum and bilateral large purulent effusions of her knees. She had no evidence of underlying rheumatoid arthritis or a specific seronegative spondyloarthropathy. Of note she had a history of Graves' disease for which she had been treated with propylthiouracil for 3 years and on investigation at this presentation had a markedly elevated perinuclear antineutrophil cytoplasm antibody (P-ANCA) level with specificities for IgM myeloperoxidase, IgG elastase and IgG lactoferrin. We believe this patient had pyoderma gangrenosum with secondary sterile pyarthrosis and a P-ANCA precipitated by propylthiouracil.

On the assessment of statistical significance in disease-gene discovery

One of the major challenges facing genome-scan studies to discover disease genes is the assessment of the genomewide significance. The assessment becomes particularly challenging if the scan involves a large number of markers collected from a relatively small number of meioses. Typically, this assessment has two objectives: to assess genomewide significance under the null hypothesis of no linkage and to evaluate true-positive and false-positive prediction error rates under alternative hypotheses. The distinction between these goals allows one to formulate the problem in the well-established paradigm of statistical hypothesis testing. Within this paradigm, we evaluate the traditional criterion of LOD score 3.0 and a recent suggestion of LOD score 3.6, using the Monte Carlo simulation method. The Monte Carlo experiments show that the type I error varies with the chromosome length, with the number of markers, and also with sample sizes. For a typical setup with 50 informative meioses on 50 markers uniformly distributed on a chromosome of average length (i.e., 150 cM), the use of LOD score 3.0 entails an estimated chromosomewide type I error rate of.00574, leading to a genomewide significance level >.05. In contrast, the corresponding type I error for LOD score 3.6 is.00191, giving a genomewide significance level of slightly <.05. However, with a larger sample size and a shorter chromosome, a LOD score between 3.0 and 3.6 may be preferred, on the basis of proximity to the targeted type I error. In terms of reliability, these two LOD-score criteria appear not to have appreciable differences. These simulation experiments also identified factors that influence power and reliability, shedding light on the design of genome-scan studies.

Approached to monitoring the results of long-term disease prevention trials: examples from the Women's Health Initiative

We contrast monitoring therapeutic trials with monitoring prevention trails. We argue that in monitoring prevention trials one should place more emphasis on formally defined global measures of health, not simply on a single targeted disease, particularly when an intervention may reduce the incidence of some diseases but increase the incidence of others. We describe one approach, illustrated by the Women's Health Initiative. For each of several sets of hypothetical interim results ("scenarios"), members of the Data and Safety Monitoring Committee (DSMC) were asked whether they would continue or stop the trial. In parallel with this exercise, various statistical methods of monitoring that are based on (1) the primary targeted disease, (2) a combination of various disease outcomes, or (3) a mixture of both were applied to these scenarios. One objective was to find a statistical approach that mirrors the majority view of the DSMC. A second objective was to stimulate discussion among DSMC members in preparation for their task of monitoring the trial as the real data become available. We found that no single method fully matched the majority vote of the DSMC. However, a mixed approach requiring the primary outcome to be significant and the global index to be "supportive," with separate monitoring of adverse effects, corresponded with the majority vote quite well. This approach maintains the emphasis on the primary hypothesis while assuring that broader safety and ethical issues of multiple diseases are incorporated.

The Women's Health Trial Feasibility Study in Minority Populations: design and baseline descriptions

The Women's Health Trial: Feasibility Study in Minority Populations (WHT:FSMP), a randomized trial of 2208 women, was conducted to investigate three questions. First, can women from minority and low-socioeconomic-status populations be recruited in numbers sufficient to evaluate a dietary intervention designed to lower fat intake. Second, the efficacy of a low fat, increased fruit/vegetable/ grain product intervention for reducing fat consumption. Third, will participation in the intervention lower plasma cholesterol and estradiol levels relative to the controls. The baseline results showed that an adequate number of minority and low SES women could be recruited to test the study hypotheses. A diverse study population of postmenopausal women consuming a high fat diet was recruited: 28% of participants were Black, 16% were Hispanic, 11% had less than a high school level of education, and 15.5% had household incomes of < $15,000.

A review of the association of estrogens and progestins with cardiovascular disease in postmenopausal women

The purpose of this article was to review, with special attention to the hypothesized mechanisms of atherosclerosis and thrombosis, the literature on the association of estrogens and progestins with cardiovascular disease. The data sources included recent reviews and their citations as well as literature searches of Medline. For coronary heart disease, we relied on a recent meta-analysis; for the lipid effects of estrogens and progestins, we refer to recent reviews and studies; for stroke, we identified all cohort and case-control studies; and for the effects of hormones on coagulation factors, we identified all relevant studies. The lipid effects of estrogens in postmenopausal women probably prevent atherosclerosis, and we would expect long duration of use rather than current use to provide the greatest benefit. Few epidemiologic studies have, however, assessed duration of estrogen use. High doses of estrogens are likely to be thrombogenic during current use, and it is possible that even moderate doses may increase the risk of clotting among women who smoke or who have existing coronary atherosclerosis. Compared with the lipid effects of estrogens alone, the lipid effects of combined therapy with progestins may increase atherosclerosis. The effect of progestins on coagulation factors is largely unknown, and no epidemiologic study has assessed the risk of cardiovascular disease associated with the use of combined hormone therapy in postmenopausal women. Cardiovascular risk or benefit associated with the use of postmenopausal hormones may involve several competing mechanisms, including effects on prostaglandins and vascular tone as well as atherosclerosis and thrombosis.

Cholestatic jaundice associated with captopril therapy

Captopril has attained widespread use as an effective agent in the treatment of heart failure and hypertension. Dermatological, renal and haematological toxicity associated with its use has been widely described and is usually well recognized. There have been comparatively few reports implicating it as causing hepatic drug reactions. Most descriptions have emphasized strongly cholestatic features, although a mixed hepatocellular cholestatic picture and predominant hepatocellular reactions have been reported. Between November 1972 and June 1990 only five cases of possible Captopril-associated hepatic dysfunction were reported to the Australian Adverse Drug Reaction Advisory Committee. Cases reported suggest equal sex distribution, latent period to development of abnormality between 1 week and 20 months, with slow resolution of jaundice and biochemical abnormality from 1 week to 6 months after withdrawal of the drug. One case of hepatic coma and death with massive acute hepatic necrosis on biopsy has been reported. Not uncommonly the accompanying systemic features suggest a syndrome of drug hypersensitivity. We report a case of Captopril-induced cholestatic jaundice in which the abnormality occurred 2 weeks after commencement of the drug and resolved slowly upon discontinuation. The case illustrates two important points: first, the importance of taking a full history, obtaining detailed information about previous drug administration in patients admitted with jaundice; and second, in the case of Captopril-induced liver disease, the jaundice may persist for many weeks after drug withdrawal.

Improved survival in patients with poor-prognosis malignant melanoma treated with adjuvant levamisole: a phase III study by the National Cancer Institute of Canada Clinical Trials Group

Five hundred forty-three patients with completely resected malignant melanoma who were considered to have a significant risk of developing recurrent disease were randomized to one of four study groups. One group received levamisole 2.5 mg/kg on 2 consecutive days weekly for 3 years, a second group received bacillus Calmette-Guérin (BCG) for 3 years. A third group alternated 8-week courses of BCG and levamisole for 3 years and a fourth group underwent clinical assessment at the same frequency as the three treatment groups. The median duration of follow-up is 8.5 years. The percentage of reduction in the death rate and the recurrence rate in the treatment groups compared with the control group was calculated using the Cox proportional hazards model and adjusted for age, sex, and stage as covariants. The patients treated with levamisole were estimated to have a 29% reduction in both the death rate (P = .08) and the recurrence rate (P = .09) compared with patients receiving no further treatment. Fifty-five patients discontinued levamisole early because of gastrointestinal intolerance or arthralgia, myalgia, fever, and immune leukopenia. The patients treated with BCG alternating with levamisole experienced a 10% reduction in the death rate and a 6% reduction in the recurrence rate, and the patients treated with BCG alone experienced a 4% reduction in the death rate and a 3% increase in the recurrence rate compared with the control group. The degree of improvement experienced by the patients that were treated by levamisole is of sufficient magnitude to warrant further investigation of this dose of levamisole as adjuvant treatment in patients with melanoma.

Joint estimation of recombination fractions and interference coefficients in multilocus linkage analysis

Estimation of recombination fractions and interference coefficients is of importance in multilocus linkage analysis. With the development of molecular genetic technologies such as RFLP, multilocus data are readily available to researchers. Several methods have been developed to analyze such data, and each performs well under restrictive conditions. The present paper proposes a method based on a multiplicative model and maximum-likelihood estimation of recombination fractions and interference coefficients. The estimators are consistent regardless of the model assumptions and are efficient if the model is a good approximation. The estimators are tractable even when there are incomplete observations. Furthermore, the interference between nonadjacent chromosomal regions or those among three chromosomal regions can be modeled and tested by a simple Z-test. The proposed method was applied to linkage analysis of four-locus data obtained from Drosophila and that of seven-locus data obtained again from Drosophila. Reanalysis of the first example revealed that there is interference between chromosomal regions 2 and 3. Analysis of the second example suggested that there is triple interference as well as pairwise interference between nonadjacent chromosomal regions; the genetic interpretation of these findings remains to be developed.

Analysis of the costs of a large prevention trial

Total direct costs of the Women's Health Trial (WHT), a large multicenter prevention trial, were reduced by more than 50% by means of research cost analysis conducted during the trial design phase. The unit costs of specific trial activities were estimated so that total direct costs of the trial could be predicted from design parameters. The relative costs of screening, treatment, and follow-up, and the fixed costs associated with each clinical center in a multicenter prevention trial were taken into account. Direct costs of the WHT were reduced from +195 million to +95 million by refinement of the trial protocol, selection of an efficient design, and consideration of trial logistics. The analyses suggest several ways to reduce costs in a prevention trial. Use of the case-cohort approach can reduce costs substantially when the protocol includes collection of specimens or data that are costly to process. When establishing and maintaining a clinical center represents a significant proportion of a clinical center's costs, use of a smaller number of larger clinical centers offers important cost savings. Because restrictive eligibility requirements reduce the recruitment potential of each clinical center, use of high-risk participants may not improve the efficiency of a prevention trial; its favorable impact on sample size may fail to compensate for its cost in terms of additional clinical centers and higher recruitment costs.

Dietary fat reduction and plasma estradiol concentration in healthy postmenopausal women. The Women's Health Trial Study Group

Concentrations of total and weakly bound plasma estradiol were significantly (P less than .01) reduced in 73 healthy post-menopausal women after 10-22 weeks of participation in a low-fat diet intervention program. Nonsignificant reductions in estrone sulfate and sex hormone-binding protein were also observed. The 17% reduction in average estradiol concentration was accompanied by an average reduction of 12 mg/dL in total plasma cholesterol (P less than .001), an average weight loss of 3.4 kg (P less than .001), and an average reduction in daily dietary fat from 68.5 to 29.5 g. Our review of case-control studies indicates that a 17% reduction in plasma estradiol may explain a noteworthy component of the international variation in breast cancer incidence. We find a need for further studies of (a) disease risk in relation to hormone concentrations and (b) changes in hormone concentrations as a function of the duration of low-fat diet intervention.

Statistical design of the Women's Health Trial

The National Cancer Institute has initiated a randomized trial to determine whether a low fat diet can reduce the incidence of breast cancer among women at increased risk for this disease. A feasibility trial involving 303 women has been conducted to examine recruitment strategies, study short-term compliance and, more generally, develop and refine trial procedures. The feasibility trial group also developed a detailed full-scale trial design plan, and randomization of participants to such a trial is currently underway. The purpose of this report is to describe the major design features of this Women's Health Trial, with particular emphasis on the statistical aspects of the design. The trial is planned to last 10 years and to include 32,000 participants. Of these 32,000 women, 12,800 will be assigned to a low fat diet intervention, and the other 19,200 will constitute a control group. The sample size of 32,000 arises from a range of estimates and assumptions pertaining to (a) the incidence of breast cancer at enrollment corresponding to selected eligibility criteria, (b) the relative risk of breast cancer as a function of a woman's history of dietary fat intake, (c) compliance assumptions in terms of average percent fat in the intervention and control groups as a function of time from randomization, and (d) rates of competing causes of death. These estimates and assumptions will be discussed, as will the robustness of the intended sample sizes to departures from such design assumptions.

Lymphocytic bronchitis unrelated to acute graft-versus-host disease in canine marrow graft recipients

We reviewed coded autopsy material from 71 dogs, 46 receiving allogeneic and 25 receiving autologous bone marrow transplants, to evaluate the hypothesis that lymphocytic bronchitis is associated with severe acute graft-versus-host disease (GVHD). We found no significant correlation between the presence of lymphocytic bronchitis and severe acute GVHD (P greater than 0.16). Using a binary regression model that corrected for possible confounding relationships, we failed to show a correlation between lymphocytic bronchitis and acute GVHD of each of the 3 classically affected organ systems. Also, no correlation was found between lymphocytic bronchitis and acute bacterial pneumonia (P greater than 0.32). Finally, lymphocytic bronchitis was present in autografted dogs with a prevalence at autopsy not significantly different from that of allografted dogs (P greater than 0.32). We conclude that lymphocytic bronchitis in this canine model represents nonspecific inflammation rather than acute pulmonary GVHD.

Recovery of in vivo cellular immunity after human marrow grafting. Influence of time postgrafting and acute graft-versus-host disease

Three hundred thirty-two marrow graft recipients and 241 healthy marrow donors were studied by skin testing with recall and neoantigens. Two hundred thirty patients with leukemia and seventy-eight patients with aplastic anemia received allogeneic HLA-identical sibling marrow. Twenty-four patients with leukemia received syngeneic marrow. The conditioning regimen prior to marrow infusion consisted of 120 mg/kg cyclophosphamide and 9.2-15.75 Gy total-body irradiation (leukemia) or 200 mg/kg cyclophosphamide (aplastic anemia). The patients were skin-tested with the neoantigens dinitrochlorobenzene (DNCB), keyhole limpet hemocyanin, and a battery of five recall antigens around 100, 150, 365, 730, 1095, 1460, and 1825 days after grafting. A binary logistic regression analysis was used to investigate the factors thought to influence immunocompetence. At 3 months postgrafting, the proportion of patients positive to DNCB was equal to that of normal marrow donors, but thereafter it was lower until 2 years. The proportion of patients positive to keyhole limpet hemocyanin was lower than normal regardless of the time after grafting. The proportion of patients positive to recall antigens was lower than that of normal marrow donors until 4 years after grafting. Patients with a history of acute graft-versus-host disease had the lowest probability of a positive reaction to recall antigens. None of the other factors was significantly associated with an increased or reduced level of response.

Increased incidence of malignant tumors in dogs after total body irradiation and marrow transplantation

One hundred fifty-three dogs were given 6.1-21.3 Gy total body irradiation at 0.02-0.2 Gy/minute delivered from two opposing cobalt sources followed by allogeneic (131 dogs) or autologous (22 dogs) marrow grafts and observed for 6-127 (median 33) months. The incidence of malignant tumors in radiation chimeras was compared to that in 242 untreated dogs observed for 6-188 (median 81) months. Thirteen malignancies were observed in 11 radiation chimeras. These tumors included two leiomyosarcomas of the mesentery, four adenocarcinomas of the breast, prostate and ovary, two mastocytomas, one hypernephroma, perianal gland carcinoma, seminoma, Brenner tumor, and an oligodendroglioma. Fifty-four malignancies were seen in 44 control dogs. These included 12 mammary carcinomas, 12 thyroid carcinomas, six lymphomas, two malignant melanomas, and a number of other solid tumors. On the basis of time-dependent Cox regression analysis, radiation chimeras had an estimated relative risk of developing a malignancy that was 5-fold higher than in control dogs (p less than 0.001). No tumor has yet been observed in a group of 15 chimeras conditioned by cyclophosphamide or dimethyl busulfan and followed for 6-97 (median 24) months. The increased risk of cancer among canine radiation chimeras suggests that high-dose total body irradiation may increase the risk of developing a malignancy and should be avoided whenever possible in the conditioning for marrow transplantation of human patients with nonmalignant diseases.

Antileukemic effect of graft-versus-host disease in human recipients of allogeneic-marrow grafts

To determine whether allogeneic bone-marrow transplantation is associated with a graft-versus-leukemia effect, we examined the relation between relapse of leukemia and graft-versus-host disease in 46 recipients of identical-twin (syngeneic) marrow, 117 recipients of HLA-identical-sibling (allogeneic) marrow with no or minimal graft-versus-host disease, and 79 recipients of allogeneic marrow with moderate to severe or chronic disease. The relative relapse rate was 2.5 times less in allogeneic-marrow recipients with graft-versus-host disease than in recipients without it (P less than 0.01). This apparent antileukemic effect was more marked in patients with lymphoblastic than nonlymphoblastic leukemia, and in those who received transplants during relapse rather than during remission, and was most evident during the first 130 days after transplantation. Survival of all patients was comparable since the lesser probability of recurrent leukemia in patients with graft-versus-host disease was offset by a greater probability of other causes of death.

Use of the logistic model in retrospective studies

A logistic regression model is used to study the association between a dichotomous exposure variable and a disease. The method takes into account factors that may confound the association and leads to a quantitative study of the influence of factors which are related to the strength of the association. Special results are given for matched pair data. A case-control study relating post-menopausal estrogen use and endometrial cancer provides illustration.

Association of exogenous estrogen and endometrial carcinoma

To determine the association between the incidence of endometrial cancer and the use of estrogen in menopausal and post-menopausal women, we retrospectively compared 317 patients with adenocarcinoma of the endometrium with an equal number of matched controls having other gynecologic neoplasms; 152 patients used estrogen, as compared to 54 of 317 controls. Thus, the risk of endometrial cancer was 4.5 times greater among women exposed to estrogen therapy. When estrogen use was adjusted for concomitant variables such as obesity, hypertension, diabetes, parity, referral pattern, age at diagnosis, year of diagnosis and other gynecologic neoplasms, the magnitude of the increased relative risk was associated with several of these variables, and was highest in patients without obesity and hypertension. Exogenous estrogen therapy is associated with an increased risk of endometrial carcinoma, but this increased relative risk is less apparent in patients with physiologic characteristics previously associated with an increased risk.