Concomitant use of statins and sodium-glucose co-transporter 2 inhibitors and the risk of myotoxicity reporting: A disproportionality analysis.

AIMS: Recent case reports have suggested that sodium-glucose co-transporter 2 (SGLT2) inhibitors may interact with statins to increase their risk of myotoxicity. We assessed the risk of myotoxicity reporting associated with concomitant use of SGLT2 inhibitors and statins. METHODS: We queried the US Food and Drug Administration Adverse Event Reporting System (FAERS) from 2013 to 2021 for reports including SGLT2 inhibitors, statins or both. We estimated several measures of disproportionate reporting of myopathy and rhabdomyolysis associated with concomitant use of SGLT2 inhibitors and statins: reporting odds ratio (ROR) with 95% confidence interval (CI), Ω shrinkage measure (safety signal if >0) and an extension of the proportional reporting ratio (PRR) (two-criteria set, safety signal if both criteria are met), using the full FAERS dataset as the reference set. In sensitivity analyses, we focussed on specific SGLT2 inhibitor-statin pairs with higher interaction potential (canagliflozin-rosuvastatin, empagliflozin-rosuvastatin) and accounted for stimulated reporting. RESULTS: There were 456 myopathy and 77 rhabdomyolysis reports involving both an SGLT2 inhibitor and a statin. Concomitant use of SGLT2 inhibitors and statins was not associated with an increased risk of myopathy (ROR 0.79, 95% CI 0.70 to 0.89) or rhabdomyolysis (ROR 0.58, 95% CI 0.41 to 0.83) reporting. For both outcomes, the Ω shrinkage measure was negative and only one criterion of the PRR extension was met. SGLT2 inhibitor-statin pairs with higher interaction potential yielded potential signals for rhabdomyolysis; these signals disappeared after accounting for stimulated reporting. CONCLUSION: There was no increased risk of myotoxicity reporting associated with concomitant use of SGLT2 inhibitors and statins or for specific drug pairs.

Systematic review and meta-analysis of adverse cardiovascular events associated with proton pump inhibitors used alone or in combination with antiplatelet agents.

The potential association between major adverse cardiovascular events (MACE) and concomitant treatment with proton pump inhibitors (PPIs) and clopidogrel has been debated since 2009. Recent reports, however, suggest that PPIs may increase the risk of MACE independently of clopidogrel. This review evaluates epidemiological findings relevant to the association between PPIs, taken alone or concomitantly with antiplatelets, and the risk of MACE. A systematic review and meta-analysis were conducted. Relevant studies were identified from MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials and then screened. Included studies were categorized into three groups: Group A: PPIs versus no PPIs; Group B: combined PPIs and clopidogrel versus clopidogrel alone; Group C: combined PPIs and other drugs versus other drugs. Pooled risk ratios (RRs) were calculated for each outcome of interest in each comparison group. Of the 1667 studies identified, 118 were included in the systematic review, of which 66 were included in the meta-analyses. Among Group A observational studies, RRs for MACE outcomes were statistically significant for some patient populations but not others. Pooled RRs from Group A RCTs were not statistically significant for any outcome. Pooled RRs for Group B observational studies were statistically significant for all-cause mortality and MI, but were diminished in magnitude when pooling was restricted to propensity score matched studies or post hoc analyses of RCTs. Group C studies did not demonstrate an association with MACE. Findings do not consistently support an association between MACE and PPIs when taken alone, or concomitantly with antiplatelets.

Trends in concomitant clopidogrel and proton pump inhibitor treatment among ACS inpatients, 2000-2016.

PURPOSE: The US Food and Drug Administration (FDA) issued three safety announcements between January 2009 and October 2010 warning against concomitant use of clopidogrel and proton pump inhibitors (PPIs) due to a potential drug-drug interaction that may attenuate clopidogrel's antiplatelet activity. This primary objective of this study was to examine trends in concomitant clopidogrel/PPI use among acute coronary syndrome (ACS) inpatients in the US between 2000 and 2016, in relation to the FDA safety communications. METHODS: Adult inpatients with a primary diagnosis of ACS were identified from the Cerner Health Facts® database. The standardized (age, sex, race, and census region) prevalence of clopidogrel use with PPIs was calculated yearly and quarterly. Findings were stratified by PPIs' potential to inhibit clopidogrel's activity and by age. RESULTS: A total of 204,533 inpatients were identified. In 2008, the prevalence of concomitant clopidogrel and PPI treatment was 34.9%, decreasing to 24.4 and 16.4% in 2009 and 2010, respectively, with the decline being similar across age groups. Treatment with inhibiting PPIs (omeprazole and esomeprazole) and clopidogrel has continued to decrease since 2010, with a prevalence of 0.8% in 2016. A similar reduction was not observed with clopidogrel and non-inhibiting PPIs (pantoprazole, lansoprazole, rabeprazole, and dexlansoprazole). During the FDA warning period, the combined treatment with clopidogrel and H2 receptor antagonists, an alternative to PPIs suggested by the FDA, temporarily increased from 7.8% in 2008 to 12.8 and 14.5% in 2009 and 2010, respectively. CONCLUSIONS: Findings suggest that clinical practice recommendations made by the FDA were followed. Further research is needed to determine how changes in drug labels and the availability of new drugs may have influenced the observed trends.

Thiazolidinedione drugs in the treatment of type 2 diabetes mellitus: past, present and future.

Thiazolidinedione (TZD) drugs used in the treatment of type 2 diabetes mellitus (T2DM) have proven effective in improving insulin sensitivity, hyperglycemia, and lipid metabolism. Though well tolerated by some patients, their mechanism of action as ligands of peroxisome proliferator-activated receptors (PPARs) results in the activation of several pathways in addition to those responsible for glycemic control and lipid homeostasis. These pathways, which include those related to inflammation, bone formation, and cell proliferation, may lead to adverse health outcomes. As treatment with TZDs has been associated with adverse hepatic, cardiovascular, osteological, and carcinogenic events in some studies, the role of TZDs in the treatment of T2DM continues to be debated. At the same time, new therapeutic roles for TZDs are being investigated, with new forms and isoforms currently in the pre-clinical phase for use in the prevention and treatment of some cancers, inflammatory diseases, and other conditions. The aims of this review are to provide an overview of the mechanism(s) of action of TZDs, a review of their safety for use in the treatment of T2DM, and a perspective on their current and future therapeutic roles.

Completeness of serious adverse drug event reports received by the US Food and Drug Administration in 2014.

PURPOSE: Adverse drug event reports to the US Food and Drug Administration (FDA) remain the primary tool for identifying serious drug adverse effects without adequate existing warnings. We assessed the completeness of reports the FDA received in 2014. METHODS: Serious adverse drug event reports were evaluated for whether they included age, gender, event date, and at least one medical term describing the event in computer excerpts. Report sources were direct reports to the FDA, manufacturer expedited reports about events without adequate warnings, and manufacturer periodic reports about events with existing warnings. RESULTS: In 2014, the FDA received 528,192 new case reports indicating a serious or fatal outcome, 25,038 (4.7%) directly from health professionals and consumers, and 503,154 (95.3%) from drug manufacturers. Overall, 21,595 (86.2%) of serious reports submitted directly to the FDA provided data for all four completeness variables, compared with 271,022 (40.4%) of manufacturer expedited reports and 24,988 (51.3%) of periodic reports. Among manufacturer serious reports, 37.9% lacked age and 46.9% had no event date. Performance by 25 manufacturers submitting 5000 or more reports varied from 24.4% complete on all variables to 67% complete. Patient death cases had the lowest completeness scores in all categories. CONCLUSIONS: By these measures, report completeness from drug manufacturers was poor compared with direct submissions to the agency. The FDA needs to update reporting requirements and compliance policies to help industry capture better adverse event information from new forms of manufacturer interactions with health professionals and consumers. Copyright © 2016 John Wiley & Sons, Ltd.

Demonstration of early efficacy results of the delayed-release combination of doxylamine-pyridoxine for the treatment of nausea and vomiting of pregnancy.

BACKGROUND: Nausea and vomiting of pregnancy (NVP) affects up to 80% of expecting mothers. In April 2013 the FDA approved the delayed-release combination of doxylamine succinate and pyridoxine hydrochloride (Diclegis®) for NVP, based in part, on the results of a phase III randomized trial demonstrating the efficacy of this drug combination [study drug marketed under the trade name Diclectin® in Canada and Diclegis® in the United States] compared to placebo in pregnant women. Study drug dosing occurred for 14 days, which is substantially longer than what has been performed in similar studies. The objective of this study was to evaluate, through secondary analysis, whether the primary measure of efficacy can be demonstrated after five days of treatment. METHODS: Women suffering from NVP were randomized to receive Diclegis® (n = 131) or placebo (n = 125) for 14 days at doses ranging from two to four tablets a day, based on a pre-specified titration protocol. The primary efficacy endpoint was the change in the validated Pregnancy-Unique Quantification of Emesis (PUQE) score at baseline versus Day 15 between Diclegis®-treated and placebo-treated women. For the present study, the change in PUQE score between baseline and Day 15 (end of the study) was compared to the changes observed for Days 3, 4, and 5. RESULTS: The use of delayed-release doxylamine succinate and pyridoxine hydrochloride tablets show improved NVP symptom control as compared to placebo on Days 3,4 and 5, with sustained efficacy until the end of the trial. CONCLUSION: A four day study drug dosing trial with Diclegis® is sufficient to document efficacy, as the results are similar to those achieved after 14 study drug dosing days. The benefit seen at the earlier time validates drug efficacy and minimizes the natural course of improvement. TRIAL REGISTRATION: CTR No. NCT006 14445 2007.

Improving Concordance in Environmental Epidemiology: A Three-Part Proposal.

In observational research, evidence is usually derived from multiple studies, and any single result is rarely considered sufficient for public health decision making. Despite more than five decades of research and thousands of studies published, the ability to draw robust conclusions regarding the presence or absence of causal links between specific environmental exposures and human health remains limited. To develop policies that are protective of public health and can withstand scrutiny, agencies need to rely on investigations of satisfactory quality that follow sufficiently concordant protocols in terms of exposure assessment, outcome ascertainment, data analysis, and reporting of results. Absent such concordance, the ability of environmental epidemiology studies to inform decision making is greatly diminished. Systems and tools are proposed here to improve concordance among environmental epidemiology studies. Specifically, working systems in place in other fields of research are critically examined and used as guidelines to develop analogous policies and procedures for environmental epidemiology. A three-part path forward toward more concordant, transparent, and readily accessible environmental epidemiology evidence that parallels ongoing efforts in medical research is proposed. The three parts address methods for improving quality and accessibility of systematic reviews, access to information on ongoing and completed studies, and principles for reporting. The goals are to increase the value of epidemiological research in public health decision making and to stimulate discussions around solutions proposed herein.

Maternal safety of the delayed-release doxylamine and pyridoxine combination for nausea and vomiting of pregnancy; a randomized placebo controlled trial.

BACKGROUND: Nausea and vomiting of pregnancy (NVP) is the most common medical condition in pregnancy, affecting up to 80% of expecting mothers. In April 2013 the FDA approved the delayed release combination of doxylamine succinate and -pyridoxine hydrochloride (Diclegis®) for NVP, following a phase 3 randomized trial in pregnant women. The fetal safety of this medication has been proven by numerous studies. However, because it is the only FDA-approved medication for NVP that is likely to be used by a large number of pregnant women, its maternal safety is an important public health question. The Objective is to evaluate the maternal safety of doxylamine succinate -pyridoxine hydrochloride delayed-release preparation (Diclegis® as compared to placebo. METHODS: We randomized women suffering from NVP to receive Diclegis® (n = 131) or placebo (n = 125) for 14 days at doses ranging from 2-4 tablets a day, based on a pre-specified titration protocol response to symptoms. Adverse events were collected through patient diaries, clinical examination and laboratory testing. RESULTS: Doxylamine succinate 10 mg and pyridoxine hydrochloride 10 mg use was not associated with an increased rate of any adverse event over placebo, including CNS depression, gastrointestinal or cardiovascular involvement. CONCLUSIONS: Doxylamine succinate-pyridoxine hydrochloride delayed release combination is safe and well tolerated by pregnant women when used in the recommended dose of up to 4 tablets daily in treating nausea and vomiting of pregnancy. TRIAL REGISTRATION: Clinical Trial Registration No: NCT00614445 .

Bisphenol A and indicators of obesity, glucose metabolism/type 2 diabetes and cardiovascular disease: a systematic review of epidemiologic research.

INTRODUCTION: Bisphenol A (BPA), a high-volume chemical with weak estrogenic properties, has been linked to obesity, cardiovascular diseases (CVD) and diabetes mellitus (DM). This review evaluates both the consistency and the quality of epidemiological evidence from studies testing the hypothesis that BPA exposure is a risk factor for these health outcomes. METHODS: We followed the current methodological guidelines for systematic reviews by using two independent researchers to identify, review and summarize the relevant epidemiological literature on the relation of BPA to obesity, CVD, DM, or related biomarkers. Each paper was summarized with respect to its methods and results with particular attention to study design and exposure assessment, which have been cited as the main areas of weakness in BPA epidemiologic research. As quantitative meta-analysis was not feasible, the study results were categorized qualitatively as positive, inverse, null, or mixed. RESULTS: Nearly all studies on BPA and obesity-, DM- or CVD-related health outcomes used a cross-sectional design and relied on a single measure of BPA exposure, which may result in serious exposure misclassification. For all outcomes, results across studies were inconsistent. Although several studies used the same data and the same or similar statistical methods, when the methods varied slightly, even studies that used the same data produced different results. CONCLUSION: Epidemiological study design issues severely limit our understanding of health effects associated with BPA exposure. Considering the methodological limitations of the existing body of epidemiology literature, assertions about a causal link between BPA and obesity, DM, or CVD are unsubstantiated.

Do phthalates act as obesogens in humans? A systematic review of the epidemiological literature.

INTRODUCTION: Phthalates, a class of commonly used compounds with widespread human exposure, have been described as obesogens, or chemicals that disrupt lipid metabolism and produce metabolic changes leading to increased risk of type 2 diabetes mellitus (DM) and cardiovascular disease (CVD). This communication provides a systematic review of the available epidemiologic evidence on associations between phthalate ester metabolites in urine or blood and various health endpoints related to overweight/obesity, DM or CVD. METHODS: We followed the current methodological guidelines for systematic reviews to identify, retrieve and summarize the relevant epidemiological literature on the relation between phthalates and overweight/obesity, DM, CVD or related biomarkers. Each eligible paper was summarized with respect to methods and results with particular attention to study design and exposure assessment. As quantitative meta-analysis was not feasible, the study results were assessed qualitatively for inter- and intra-study consistency. RESULTS: We identified 26 publications of epidemiologic studies that assessed associations between either urinary or serum phthalate metabolites and outcomes of interest. These studies represented 18 independent data sources. We found no inter- or intra-study consistency for any phthalate metabolite for any of the indicators of overweight/obesity, DM or CVD in children or adults. Most reported associations were not statistically significantly different from the null, some were positive, and others were inverse. All studies except two used cross-sectional analyses and for this reason could not be used to test causal hypotheses. CONCLUSION: The current epidemiological data do not support or refute the hypothesis that phthalates act as obesogens in humans.

Pharmaco- and toxicokinetics of selected exogenous and endogenous estrogens: a review of the data and identification of knowledge gaps.

Chemicals with estrogenic activity are derived from many different natural and synthetic processes and products, including endogenous production (e.g., estradiol, conjugated estrogens), drugs (e.g., ethinyl estradiol, conjugated estrogens), plants used as foods (phytoestrogens such as genistein, daidzein, S-equol), and man-made chemicals (xenoestrogens such as bisphenol A). Human exposure to low doses of endogenous estrogens, estrogenic drugs, phytoestrogens, and xenoestrogens has the potential to improve health or disrupt normal endocrine activity, as well as impact the diverse systems with which estrogens interact, including the cardiovascular system, and lipid and carbohydrate metabolism. Mechanisms of action and diversity of adverse and non-adverse effects following human exposure to low doses of estrogen active chemicals (EACs, defined as chemicals which interact with an estrogen receptor [ER]) are poorly understood. This review summarizes our current understanding of the pharmacological action with a focus on pharmacokinetics (PK) and toxicokinetics (TK) of several representative EACs in both physiological and pathological processes. The goal of this review is to assess the current state-of-the-science on: (i) the potential for EACs to interfere with endocrine activity, (ii) factors which contribute to endocrine-related clinical outcomes, and (iii) existing knowledge gaps. While classical PK approaches (compartmental or non-compartmental) can be used to characterize absorption, distribution, metabolism, and elimination of EACs, many of the detailed pharmacological characteristics necessary to understand benefit-risk balance have not yet been clarified. Pharmacological complexities mirror the complexity of determining whether and under what conditions exposure to estrogens in drugs, foods or to xenoestrogenic chemicals are beneficial or harmful to human health.

Pubertal delay in male nonhuman primates (Macaca mulatta) treated with methylphenidate.

Juvenile male rhesus monkeys treated with methylphenidate hydrochloride (MPH) to evaluate genetic and behavioral toxicity were observed after 14 mo of treatment to have delayed pubertal progression with impaired testicular descent and reduced testicular volume. Further evaluation of animals dosed orally twice a day with (i) 0.5 mL/kg of vehicle (n = 10), (ii) 0.15 mg/kg of MPH increased to 2.5 mg/kg (low dose, n = 10), or (iii) 1.5 mg/kg of MPH increased to 12.5 mg/kg (high dose, n = 10) for a total of 40 mo revealed that testicular volume was significantly reduced (P < 0.05) at months 15 to 19 and month 27. Testicular descent was significantly delayed (P < 0.05) in the high-dose group. Significantly lower serum testosterone levels were detected in both the low- (P = 0.0017) and high-dose (P = 0.0011) animals through month 33 of treatment. Although serum inhibin B levels were increased overall in low-dose animals (P = 0.0328), differences between groups disappeared by the end of the study. Our findings indicate that MPH administration, beginning before puberty, and which produced clinically relevant blood levels of the drug, impaired pubertal testicular development until ∼5 y of age. It was not possible to resolve whether MPH delayed the initiation of the onset of puberty or reduced the early tempo of the developmental process. Regardless, deficits in testicular volume and hormone secretion disappeared over the 40-mo observation period, suggesting that the impact of MPH on puberty is not permanent.

Diagnosis of manganism and manganese neurotoxicity: A workshop report.

With declining exposures to manganese (Mn) in occupational settings, there is a need for more sensitive exposure assessments and clinical diagnostic criteria for manganism and Mn neurotoxicity. To address this issue, a workshop was held on November 12-13, 2020, with international experts on Mn toxicity. The workshop discussions focused on the history of the diagnostic criteria for manganism, including those developed by the Institut de Recherche Robert-Sauvé en Santé et en Sécurité du Travail (IRSST) in Quebec in 2005 and criteria developed by the Chinese government in 2002 and updated in 2006; the utility of biomarkers of exposure; recent developments in magnetic resonance imaging (MRI) for assessing Mn accumulation in the brain and diagnosing manganism; and potential future applications of metabolomics. The suggestions of the participants for updating manganism diagnostic criteria included the consideration of: i) A history of previous occupational and environmental exposure to Mn; ii) relevant clinical symptoms such as dystonia; iii) MRI imaging to document Mn accumulation in the neural tissues, including the basal ganglia; and iv) criteria for the differential diagnosis of manganism and other neurological conditions. Important research gaps include the characterization of Mn exposure and other co-exposures, exploration of the roles of different brain regions with MRI, understanding the complexity of metal ion transporters involved in Mn homeostasis, and a need for information on other neurotransmitter systems and brain regions underlying the pathophysiology of manganism.

Non-Ergot Dopamine Agonists and the Risk of Heart Failure and Other Adverse Cardiovascular Reactions in Parkinson's Disease.

Reports suggest possible risks of adverse cardiovascular reactions, including heart failure, associated with non-ergot dopamine agonist (DA) use in Parkinson's disease (PD). The objectives of our review were to evaluate the risk of heart failure and other adverse cardiovascular reactions in PD patients who received a non-ergot DA compared with other anti-PD pharmacological interventions, placebo, or no intervention. Studies were identified via searches of six bibliographic databases. Randomized controlled trials (RCTs) and non-randomized studies (NRS) were eligible for study inclusion. Random-effect meta-analyses were performed to estimate adverse cardiovascular reaction risks. Quality of evidence was assessed using GRADE. In total, forty-four studies (thirty-six RCTs and eight NRS) satisfied our inclusion criteria. A single RCT found no significant difference in the risk of heart failure with ropinirole compared with bromocriptine (odds ratio (OR) 0.39, 95% confidence interval (CI) 0.07 to 2.04; low certainty). Conversely, three case-control studies reported a risk of heart failure with non-ergot DA treatment. The quality of evidence for the risk of heart failure was judged as low or very low. Findings suggest that non-ergot DA use may be associated with adverse cardiovascular outcomes, including heart failure. Studies are needed to better understand cardiovascular risks associated with PD treatment.

Hepatobiliary disposition of 17-OHPC and taurocholate in fetal human hepatocytes: a comparison with adult human hepatocytes.

Little information is available in the literature regarding the expression and activity of transporters in fetal human liver or cultured cells. A synthetic progesterone structural analog, 17α-hydroxyprogesterone caproate (17-OHPC), is used in the prevention of spontaneous abortion in women with a history of recurrent miscarriage (habitual abortion). 17-OHPC has been reported to traverse the placental barrier and gain access to fetal circulation. In this study, the role of transporters in the disposition of 17-OHPC in fetal and adult human hepatocytes was examined. Progesterone metabolites have been reported to induce trans-inhibition of bile acid transporter, ABCB11. Thus, we investigated the effect of 17-OHPC or its metabolites on [(3)H]taurocholic acid transport in sandwich-cultured human fetal and adult hepatocytes. 17-OHPC was taken up rapidly into the cells and transported out partially by an active efflux process that was significantly inhibited by cold temperature, cyclosporine, verapamil, and rifampin. The active efflux mechanism was observed in both adult and fetal hepatocyte cultures. 17-OHPC produced a concentration-dependent inhibition of taurocholate efflux into canaliculi in sandwich-cultured adult and fetal human hepatocytes. However, given the high concentrations required to cause inhibition of these transport processes, no adverse effects would be anticipated from therapeutic levels of 17-OHPC. We also evaluated the expression of various hepatic transporters (ABCB1, ABCB4, SLCO1B1, SLCO1B3, SLCO2B1, ABCB11, SLC10A1, ABCC2, ABCC3, ABCC4, and ABCG2) in fetal and adult hepatocytes. With the exception of ABCB4, all transporters examined were expressed, albeit at lower mRNA levels in fetal hepatocytes compared with adults.

Serum uric acid in relation to endogenous reproductive hormones during the menstrual cycle: findings from the BioCycle study.

STUDY QUESTION: Do uric acid levels across the menstrual cycle show associations with endogenous estradiol (E2) and reproductive hormone concentrations in regularly menstruating women? SUMMARY ANSWER: Mean uric acid concentrations were highest during the follicular phase, and were inversely associated with E2 and progesterone, and positively associated with FSH. WHAT IS KNOWN ALREADY: E2 may decrease serum levels of uric acid in post-menopausal women; however, the interplay between endogenous reproductive hormones and uric acid levels among regularly menstruating women has not been elucidated. STUDY DESIGN, SIZE, DURATION: The BioCycle study was a prospective cohort study conducted at the University at Buffalo research centre from 2005 to 2007, which followed healthy women for one (n = 9) or 2 (n = 250) menstrual cycle(s). PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were healthy women aged 18-44 years. Hormones and uric acid were measured in serum eight times each cycle for up to two cycles. Marginal structural models with inverse probability of exposure weights were used to evaluate the associations between endogenous hormones and uric acid concentrations. MAIN RESULTS AND THE ROLE OF CHANCE: Uric acid levels were observed to vary across the menstrual cycle, with the lowest levels observed during the luteal phase. Every log-unit increase in E2 was associated with a decrease in uric acid of 1.1% (ß = -0.011; 95% confidence interval (CI): -0.019, -0.004; persistent-effects model), and for every log-unit increase in progesterone, uric acid decreased by ≈ 0.8% (ß = -0.008; 95% CI: -0.012, -0.004; persistent-effects model). FSH was positively associated with uric acid concentrations, such that each log-unit increase was associated with a 1.6% increase in uric acid (ß = 0.016; 95% CI: 0.005, 0.026; persistent-effects model). Progesterone and FSH were also associated with uric acid levels in acute-effects models. Of 509 cycles, 42 were anovulatory (8.3%). Higher uric acid levels were associated with increased odds of anovulation (odds ratio 2.39, 95% CI: 1.25, 4.56). LIMITATIONS, REASONS FOR CAUTION: The change in uric acid levels among this cohort of healthy women was modest, and analysis was limited to two menstrual cycles. The women in this study were healthy and regularly menstruating, and as such there were few women with high uric acid levels and anovulatory cycles. WIDER IMPLICATIONS OF THE FINDINGS: These findings demonstrate the importance of taking menstrual cycle phase into account when measuring uric acid in premenopausal women, and confirm the hypothesized beneficial lowering effects of endogenous E2 on uric acid levels. These findings suggest that there could be an underlying association affecting both sporadic anovulation and high uric acid levels among young, regularly menstruating women. Further studies are needed to confirm these findings and elucidate the connection between uric acid and reproductive and later cardiovascular health.

Menstrual bleeding patterns among regularly menstruating women.

Menstrual bleeding patterns are considered relevant indicators of reproductive health, though few studies have evaluated patterns among regularly menstruating premenopausal women. The authors evaluated self-reported bleeding patterns, incidence of spotting, and associations with reproductive hormones among 201 women in the BioCycle Study (2005-2007) with 2 consecutive cycles. Bleeding patterns were assessed by using daily questionnaires and pictograms. Marginal structural models were used to evaluate associations between endogenous hormone concentrations and subsequent total reported blood loss and bleeding length by weighted linear mixed-effects models and weighted parametric survival analysis models. Women bled for a median of 5 days (standard deviation: 1.5) during menstruation, with heavier bleeding during the first 3 days. Only 4.8% of women experienced midcycle bleeding. Increased levels of follicle-stimulating hormone (ß = 0.20, 95% confidence interval: 0.13, 0.27) and progesterone (ß = 0.06, 95% confidence interval: 0.03, 0.09) throughout the cycle were associated with heavier menstrual bleeding, and higher follicle-stimulating hormone levels were associated with longer menses. Bleeding duration and volume were reduced after anovulatory compared with ovulatory cycles (geometric mean blood loss: 29.6 vs. 47.2 mL; P = 0.07). Study findings suggest that detailed characterizations of bleeding patterns may provide more insight than previously thought as noninvasive markers for endocrine status in a given cycle.

Linking drugs to obscure illnesses: lessons from pure red cell aplasia, nephrogenic systemic fibrosis, and Reye's syndrome. a report from the Southern Network on Adverse Reactions (SONAR).

Identification of serious adverse drug reactions (sADRS) associated with commonly used drugs can elude detection for years. Reye's syndrome (RS), nephrogenic systemic fibrosis (NSF), and pure red cell aplasia (PRCA) among chronic kidney disease (CKD) patients were recognized in 1951, 2000, and 1998, respectively. Reports associating these syndromes with aspirin, gadodiamide, and epoetin, were published 29, 6, and 4 years later, respectively. We obtained primary information from clinicians who identified causes of these sADRs and reviewed factors contributing to delayed identification of these toxicities. Overall, 3,500 aspirin-associated RS cases in the United States, 1,605 gadolinium-associated NSF cases, and 181 epoetin-associated PRCA cases were reported. Delays in FDA regulation of over-the- counter medications and administration of aspirin to children contributed to development of RS. For NSF, in 1996, the Danish Medicine Agency approved high-dose gadodiamide administration to chronic kidney disease (CKD) patients undergoing MR scans. Overall, 88 % of Danish NSF cases were from two hospitals and 97 % of United States' NSF cases were from 60 hospitals. These hospitals frequently administered high-doses of gadodiamide to CKD patients. Another factor was the decision to administer linear chelated contrast agents versus lower risk macrocyclic chelated agents. For PRCA, increased use of subcutaneous epoetin formulations to CKD patients, in part due to convenience and cost-savings considerations, and a European regulatory requirement requiring removal of albumin as a stabilizer, led to toxicity. Overall, 81, 13, and 17 years elapsed between drug introduction into practice and identification of a causal relationship for aspirin, erythropoietin, and gadodiamide, respectively. A substantial decline in new cases of these sADRs occurred within two years of identification of the offending drug. Clinicians should be vigilant for sADRs, even for frequently-prescribed pharmaceuticals, particularly in settings where formulation or regulatory changes have occurred, or when over-the-counter, off-label, or pediatric use is common.

The status of pharmacometrics in pregnancy: highlights from the 3(rd) American conference on pharmacometrics.

Physiological changes during pregnancy may alter drug pharmacokinetics. Therefore, mechanistic understanding of these changes and, ultimately, clinical studies in pregnant women are necessary to determine if and how dosing regimens should be adjusted. Because of the typically limited number of patients who can be recruited in this patient group, efficient design and analysis of these studies is of special relevance. This paper is a summary of a conference session organized at the American Conference of Pharmacometrics in April 2011, around the topic of applying pharmacometric methodology to this important problem. The discussion included both design and analysis of clinical studies during pregnancy and in silico predictions. An overview of different pharmacometric methods relevant to this subject was given. The impact of pharmacometrics was illustrated using a range of case examples of studies around pregnancy.

The genetic toxicity of methylphenidate: a review of the current literature.

Attention deficit/hyperactivity disorder (ADHD), a common children's behavioral disorder, is characterized by inattention, hyperactivity and impulsivity. The disorder is thought to stem from abnormalities in the catecholamine pathway and the symptoms of the disorder have been successfully treated with methylphenidate (MPH) since the FDA approved the drug in the 1950s. MPH underwent the appropriate safety testing as part of the FDA approval process; however, a publication in 2005 that reported significant increases in cytogenetic damage in the lymphocytes of MPH-treated pediatric patients caused concern for patients and their families, the pharmaceutical industry and regulatory agencies. This communication will review the many studies that were subsequently initiated worldwide to address the genetic safety of MPH in both animal models and human subjects. Animal experiments broadened the study protocols used in the 2005 investigation to include a wider dose-range, a longer treatment period and automated scoring of biological endpoints, where possible, to reduce observer bias. The human subject studies replicated the experimental design used in the 2005 study, but increased the treatment periods and the sizes of the study populations. Neither the laboratory animal nor human subject studies found an increase in any of the measures of genetic damage that were evaluated. Taken together, these new studies are consistent with the original safety evaluation of the FDA and do not support the hypothesis that MPH treatment increases the risk of genetic damage in ADHD patients. Published 2012. This article is a US Government work and is in the public domain in the USA.