Elizabeth Andrews

The causal role for genital ulcer disease as a risk factor for transmission of human immunodeficiency virus : An application of the Bradford Hill criteria

Background and Objectives: Genital ulcer disease (GUD) has been reported to increase the risk for the acquisition of human immunodeficiency virus (HIV). Although many investigators have reported an increased risk for HIV infection in persons with concurrent or previous GUD, not all studies have been designed to determine whether GUD causes an increased risk for HIV infection or acts only as a risk marker for infection. The evidence from the literature is discussed, and the criteria for causal inference proposed by Sir Austin Bradford Hill are applied. Goal: To evaluate the strength of the association between GUD and infection by HIV. Study Design: Case‐control, cross‐sectional, and cohort studies that examined the association between HIV seroconversion and GUD were chosen from the literature. Twenty‐seven epidemiologic studies were selected for analysis, many of which reported separate analyses of the association between HIV infection and herpes simplex virus infection, syphilis, or nonspecified GUD. The studies were analyzed to investigate the magnitude of association between GUD and HIV, and the evidence evaluated using Hills criteria. Results: Approximately two thirds of the analyses reported a statistically significant association between GUD and HIV infection. Fourteen studies reported 29 separate analyses using a case‐control design, 18 of which reported a statistically significant association between GUD (GUD, herpes, and syphilis) and HIV infection, four analyses were of varying significance depending on the analytical technique used, and seven were nonsignificant. Thirteen studies reported 23 separate longitudinal analyses that used a nested case‐control or cohort design: 11 reported a significant association, 11 had nonsignificant findings, and results of one study varied. No study reported a statistically significant negative association. When applying the literature to Hills criteria, all nine criteria for causal inference were met, providing additional evidence that genital ulcers are associated with an increased risk for the development of HIV infection. Conclusions: The published evidence suggests that GUD increases the risk for HIV acquisition. Few studies, however, have examined carefully the temporal association between preexisting GUD and subsequent HIV acquisition. The analyses that simultaneously controlled for additional risks for HIV infection, such as lifetime sex partners or history of injection drug use, report a generally lower risk for HIV associated with GUD. It is likely that studies that adequately control for risk factors will find a lower risk associated with GUD than was reported in the literature earlier in the HIV epidemic. Future research needs and the problems associated with conducting these types of studies are discussed.

The US postmarketing surveillance study of adult osteosarcoma and teriparatide: Study design and findings from the first 7 years

The Osteosarcoma Surveillance Study, an ongoing 15‐year surveillance study initiated in 2003, is a postmarketing commitment to the United States (US) Food and Drug Administration to evaluate a potential association between teriparatide, rhPTH(1–34), a recombinant human parathyroid hormone analog (self‐injectable medication to treat osteoporosis), and development of osteosarcoma in response to a finding from preclinical (animal) studies. Incident cases of primary osteosarcoma diagnosed in adults (aged ≥40 years) on or after January 1, 2003, are identified through population‐based state, regional, and comprehensive cancer center registries in the US. Information on possible prior treatment with teriparatide, on demographics, and on risk factors is ascertained by patient or proxy telephone interview after patient consent. Between June 2004 and September 30, 2011, 1448 cases (diagnosed 2003 to 2009) were identified by participating cancer registries (estimated to be 62% of all adult cases in the US for that time period); 549 patients or proxies were interviewed. Interviewed patients were similar to noninterviewed patients with regard to mean age, sex, race, and geographical distribution and tumor type and site of tumor. Mean age of those interviewed was 61 years, 46% were female, 86% were white, and 77% were alive when the case was reported to the study investigators. Data collected in the study provide descriptive information on a large number of adults with osteosarcoma, an uncommon malignant bone tumor. After 7 years of the study, there were no osteosarcoma patients who had a prior history of teriparatide treatment. Thus, approximately halfway through this 15‐year study, the study has not detected a pattern indicative of a causal association between teriparatide treatment and osteosarcoma in humans.

Prevalence and demographics of irritable bowel syndrome: results from a large web‐based survey

Background : Irritable bowel syndrome is a common gastrointestinal disorder, and its prevalence and demographics have been evaluated by different methodologies with varying results.

Monitoring pregnancy outcomes after prenatal drug exposure through prospective pregnancy registries: A pharmaceutical company commitment

OBJECTIVE Glaxo Wellcome becomes aware of prenatal exposures to its medications as early as the clinical trial phase of development. An international process for monitoring prenatal exposure to all Glaxo Wellcome medicines has been developed. For specific products there are prospective pregnancy registries. STUDY DESIGN The registries are observational, case-registration, and follow-up studies designed to detect evidence of teratogenicity associated with specific medications. After prenatal exposure to the registry medication, pregnancies are registered prospectively, through voluntary reports by health care providers. An advisory committee of independent scientists for each registry reviews data and advises in dissemination of information. Risk of birth defects, as defined by the Centers for Disease Control and Prevention, is compared with published risks both in women in the general population and in women with the underlying condition being treated, if available. RESULTS The following data show results from the prospective first-trimester exposures registered since establishment of each registry. The published risk of birth defects in the general population range is 3% to 5%, and the risk in women with epilepsy is 6% to 9%. The proportions of outcomes with birth defects are as follows: in the Acyclovir (antiviral medication) Pregnancy Registry (1984-1998) (19/581), 3.3% (95% confidence interval, 2.0%-5.2%); in the Lamotrigine (monotherapy and polytherapy antiepileptic medication) Pregnancy Registry (1992-September 1998) (8/123), 6.5% (95% confidence interval, 3.1%-12.8%); in the Sumatriptan (migraine medication) Pregnancy Registry (1996-October 1998) (7/183), 3.8% (95% confidence interval, 1.7%-8.0%). The Valacyclovir, Bupropion, and Naratriptan registries have insufficient data for analysis. CONCLUSION None of the registries has provided a risk estimate exceeding that expected in the disorder treated, and no pattern of defects has been observed. Whereas information from the larger registries is reassuring regarding risk, these studies cannot rule out possible small excess risks from use of these drugs in pregnancy. Data obtained through these registries are shared with the medical community as a supplement to animal toxicology studies to assist in weighing potential risks and benefits of treatment for individual patients. The success of the registries depends on the continued willingness of the obstetrics and gynecology community to notify the registries of prenatal exposures.

Evidence from multicenter neworks on the current use and effectiveness of antenatal corticosteroids in low birth weight infants

Corticosteroid treatment of pregnant women at risk for preterm delivery enhances fetal lung maturity and improves neonatal outcomes.’ Despite convincing evidence of these effects, a consensus has not been reached about the indications for antenatal steroids, and the frequency with which they are used remains low in some countries, including the United States. In response to this situation, the National Institutes of Health (NIH) convened a Consensus Development Conference on the Effects of Corticosteroids for Fetal Maturation on Perinatal Outcomes.’ The following reports were prepared at the request of the panel; they describe the effects of antenatal steroid treatment on neonatal outcome from five current observational databases: those of the National Institute of Child Health and Development (NICHD) Neonatal Research Network, the Vermont-Oxford Trials Network, Ross Laboratories, and Burroughs Wellcome (BW) Co. The purpose of this article is to present an overview of the findings of these five large databases.

Risk of suicide during treatment with venlafaxine, citalopram, fluoxetine, and dothiepin: retrospective cohort study

Objective To compare the risk of suicide in adults using the antidepressant venlafaxine compared with citalopram, fluoxetine, and dothiepin. Design Retrospective cohort study. Setting UK General Practice Research Database. Participants 219 088 patients, aged 18-89 years, who were prescribed venlafaxine, citalopram, fluoxetine, or dothiepin from 1995 to 2005. Main outcome measures Completed suicide and attempted suicide. Results Venlafaxine users had a higher burden of risk factors for suicide, including previous suicide attempts and proxies for severe depression or depression that was difficult to treat. In the analysis for completed suicides, unadjusted and adjusted hazard ratios for venlafaxine compared with citalopram were 2.44 (95% confidence interval 1.12 to 5.31) and 1.70 (0.76 to 3.80), for venlafaxine compared with fluoxetine were 2.85 (1.37 to 5.94) and 1.63 (0.74 to 3.59), and for venlafaxine compared with dothiepin were 2.54 (1.07 to 6.02) and 1.31 (0.53 to 3.25). Compared with other study drugs, venlafaxine was also associated with an increased risk of attempted suicide, but adjustment for measured confounders substantially reduced the hazard ratios. Conclusions Venlafaxine use was consistently associated with higher risk of suicide compared with citalopram, fluoxetine, and dothiepin. Venlafaxine users had a higher burden of suicide risk factors, however, and adjustment for measured confounders substantially reduced the excess risks. Since the secondary data used in this analysis allowed only indirect and partial measurements of potential confounders, it is possible that residual confounding explains much, if not all, of the observed excess risk.

RECORD LINKAGE TO CONDUCT AN EPIDEMIOLOGIC STUDY ON THE ASSOCIATION OF RHEUMATOID ARTHRITIS AND LYMPHOMA IN THE PROVINCE OF SASKATCHEWAN, CANADA

The objective of this effort was to assess the utility of the large automated database in Saskatchewan as a resource for pharmacoepidemiologic studies. To this end a study was undertaken to test the hypothesis that rheumatoid arthritis (RA) increases the risk of cancer, especially lymphoma. This was done by performing a retrospective cohort study based on record linkage data from Saskatchewan Health. From hospital discharge diagnoses in the hospital file an exposed group (RA) and two comparison groups matched to the RA group by age and sex were identified: (1) the RA group consisted of people with a discharge diagnosis of rheumatoid arthritis; (2) the osteoarthritis (OA) group consisted of people with OA discharge diagnoses; and (3) a comparison (CN) group consisted of hospitalized people with no discharge diagnoses of arthritis. Drug exposures were determined by linkage with the Prescription Drug File, cancer outcomes were determined by linkage with the Cancer Foundation file, and length of eligibility in the health plan and demographics information were determined by linkage with the registration file. The data were checked for quality of linkages across files and consistency with study definitions. Of 13,333 identified subjects, 2.8% were excluded because of apparent incorrect assignment to study group or age group or because of ineligibility in health plan during the study period. In order to decrease the possibility of misclassification of exposure (rheumatoid arthritis), hospital discharge diagnoses were used to exclude subjects with any inflammatory rheumatic diseases (IRD) from the CN (7.8%) and OA (8.3%) groups and subjects with IRD other than rheumatoid arthritis (4.6%) from the RA group. To decrease selection bias, those who had cancer within 1 year of enrollment (to exclude those in hospital because of symptoms of undiagnosed cancer) were excluded. Because RA subjects hospitalized by a rheumatologist were most likely to have valid rheumatoid arthritis diagnoses, each analysis was run twice: once with the entire RA group (N = 1210) and once with those in the RA group who were rheumatologist-hospitalized (N = 646). Logistic regression of incidence was used to control for age, sex, and use of individual disease-modifying anti-rheumatoid drugs (DMARDs). For the rheumatologist-hospitalized RA group compared to the CN group, a significant 4-fold greater risk for lymphoma/myeloma was detected when DMARD use was not controlled for, and a 3.4-fold increase in risk was detected even when use of individual DMARDs was controlled for.(ABSTRACT TRUNCATED AT 400 WORDS)

The Xolair Pregnancy Registry (EXPECT): The safety of omalizumab use during pregnancy

BACKGROUND For many asthma medications, pregnancy safety data remains insufficient. OBJECTIVE The omalizumab pregnancy registry, EXPECT, evaluates maternal, pregnancy, and infant outcomes after exposure to omalizumab, including incidence of congenital anomalies. METHODS EXPECT is a prospective, observational study of pregnant women exposed to ≥1 dose of omalizumab within 8 weeks prior to conception or at any time during pregnancy. Primary outcome measures include rates of live births, elective terminations, stillbirths, and congenital anomalies. Data were collected at enrollment, each trimester, birth, and every 6 months up to 18 months post-delivery. RESULTS As of November 2012, 188 of 191 pregnant women were exposed to omalizumab during their first trimester. Of 169 pregnancies with known outcomes (median exposure during pregnancy, 8.8 months), there were 156 live births of 160 infants (4 twin pairs), 1 fetal death/stillbirth, 11 spontaneous abortions, and 1 elective termination. Among 152 singleton infants, 22 (14.5%) were born prematurely. Of 147 singleton infants with weight data, 16 (10.9%) were small for gestational age. Among 125 singleton full-term infants, 4 (3.2%) had low birth weights. Overall, 20 infants had congenital anomalies confirmed, 7 (4.4%) of whom had 1 major defect. No pattern of anomalies was observed. CONCLUSIONS To date, proportions of major congenital anomalies, prematurity, low birth weight, and small size for gestational age observed in the EXPECT registry are not inconsistent with findings from other studies in this asthma population. Recognizing the small sample size available, no apparent increased birth prevalence of major anomalies or patterns of major anomalies has been observed.

Application of the BRAT Framework to Case Studies: Observations and Insights

The BRAT Framework is a set of flexible processes and tools that provides a structured approach to pharmaceutical benefit–risk decision making in drug development and post approval settings. A work in progress, it consists of six steps that produce representations of key tradeoffs, with appropriate documentation of the rationale for decisions and the assumptions made in their development. This article describes insights, gained from case studies, into the Frameworks performance in a variety of constructed benefit–risk scenarios, focusing on a hypothetical example of a triptan for migraine. The scenarios described illustrate the challenges inherent in arriving at many of the regulatory decisions, including obtaining data for matching populations for all outcomes, finding data of consistent quality, addressing correlated outcomes (e.g., elevated liver function tests and hepatitis rates), dealing with rare but serious adverse events (AEs), and understanding and making decisions based on information for many outcomes simultaneously. The Framework provides a structure for organizing, interpreting, and communicating relevant information, including heterogeneity in results and the quality and level of uncertainty of data, in order to facilitate benefit–risk decisions.

Determinants of healthcare-seeking behaviour among subjects with irritable bowel syndrome.

Doctor visits for irritable bowel syndrome are associated with high medical costs. Predictors of medical consultation for irritable bowel syndrome remain poorly understood.