Systematic literature review of the epidemiology of glyphosate and neurological outcomes.

Purpose: Human health risk assessments of glyphosate have focused on animal toxicology data for determining neurotoxic potential. Human epidemiological studies have not yet been systematically reviewed for glyphosate neurotoxicity hazard identification. The objective of this systematic literature review was to summarize the available epidemiology of glyphosate exposure and neurological outcomes in humans.

Tenosynovial Giant Cell Tumor: Incidence, Prevalence, Patient Characteristics, and Recurrence. A Registry-based Cohort Study in Denmark.

Objective: Tenosynovial giant cell tumor (TGCT) is a rare benign proliferative and inflammatory disease arising from synovia of joints, bursae, or tendon sheaths. We aimed to estimate incidence rate and prevalence of TGCT in Denmark, to describe patient characteristics and treatment modalities among patients with TGCT, and to estimate risk of TGCT recurrence.

Methods: Using registry data on pathology examinations and inpatient and outpatient hospital diagnoses, we identified adult patients with diagnoses of diffuse TGCT (D-TGCT) or localized TGCT (L-TGCT) between 1997 and 2012, followed through 2012.

Estimated number of prevalent cases of metastatic bone disease in the US adult population.

Background: The prevalence of metastatic bone disease in the US population is not well understood. We sought to estimate the current number of US adults with metastatic bone disease using two large administrative data sets.

Methods: Prevalence was estimated from a commercially insured cohort (ages 18-64 years, MarketScan database) and from a fee-for-service Medicare cohort (ages ≥65 years, Medicare 5% database) with coverage on December 31, 2008, representing approximately two-thirds of the US population in each age group.

Impact of Centers for Medicare & Medicaid Services national coverage determination on erythropoiesis-stimulating agent and transfusion use in chemotherapy-treated cancer patients.

Purpose: In July 2007, the Centers for Medicare & Medicaid Services released a national coverage determination (NCD) for erythropoiesis-stimulating agent (ESA) use in cancer patients, mandating payment restrictions likely to reduce ESA use and possibly increase red blood cell transfusions. We aimed to quantify ESA and transfusion use pre-NCD and post-NCD.

Methods: Medicare 5% sample data, 2005-2007, were used.

Relationship between epoetin alfa dose and mortality: findings from a marginal structural model.

Background And Objectives: Observational studies relating epoetin alfa (EPO) dose and mortality frequently use analytic methods that do not control time-dependent confounding by indication (CBI). The relationship between EPO dose and 1-year mortality, adjusting for the effects of time-dependent CBI, was examined using a marginal structural model.

Design, Setting, Participants, & Measurements: This retrospective cohort study included 27,791 hemodialysis patients between July 2000 and June 2002.

Evolving statistical methods to facilitate evaluation of the causal association between erythropoiesis-stimulating agent dose and mortality in nonexperimental research: strengths and limitations.

Findings from randomized controlled trials examining the efficacy of therapy with erythropoiesis-stimulating agents (ESAs) to normalize hemoglobin levels in patients with chronic kidney disease or kidney failure have raised questions regarding the safety of this class of drugs. However, no trial to date has specifically assessed the safety of ESA-dosing algorithms used to achieve the lower hemoglobin targets typically using in clinical practice. Although a wealth of nonexperimental data is available for dialysis patients, analyses based on these data are more susceptible to confounding bias than randomized controlled trials.

Exploring relative mortality and epoetin alfa dose among hemodialysis patients.

Background: Confounding-by-indication is a bias in nonexperimental studies that occurs when outcomes are compared for treated and untreated patients and the treatment or medication dose is related to predictors of the outcome. Two recent publications reported that greater epoetin alfa (EPO) doses were associated with increased mortality rates. We assessed whether confounding-by-indication might account for these results.

Biomonitoring of 2,4-dichlorophenoxyacetic acid exposure and dose in farm families.

Objective: We estimated 2,4-dichlorophenoxyacetic acid (2,4-D) exposure and systemic dose in farm family members following an application of 2,4-D on their farm.

Methods: Farm families were recruited from licensed applicators in Minnesota and South Carolina. Eligible family members collected all urine during five 24-hr intervals, 1 day before through 3 days after an application of 2,4-D.

Agreement of pesticide biomarkers between morning void and 24-h urine samples from farmers and their children.

In pesticide biomonitoring studies, researchers typically collect either single voids or daily (24-h) urine samples. Collection of 24-h urine samples is considered the "gold-standard", but this method places a high burden on study volunteers, requires greater resources, and may result in misclassification of exposure or underestimation of dose due to noncompliance with urine collection protocols. To evaluate the potential measurement error introduced by single void samples, we present an analysis of exposure and dose for two commonly used pesticides based on single morning void (MV) and 24-h urine collections in farmers and farm children.

Chlorpyrifos exposure in farm families: results from the farm family exposure study.

We used urinary biological monitoring to characterize chlorpyrifos (O,O-diethyl-O-(3,5,6-trichloro-2-pyridinyl) phosphororthioate) exposure to farm family members from Minnesota and South Carolina who participated in the Farm Family Exposure Study. Five consecutive 24-h urine samples were obtained from 34 families of licensed pesticide applicators 1 day before through 3 days after a chlorpyrifos application. Daily 3,5,6-trichloro-2-pyridinol (TCP) urinary concentrations characterized exposure profiles of the applicator, the spouse, and children aged 4-17 years.

Exposure misclassification in studies of agricultural pesticides: insights from biomonitoring.

Background: Epidemiologists often assess lifetime pesticide exposure by questioning participants about use of specific pesticides and associated work practices. Recently, Dosemeci and colleagues proposed an algorithm to estimate lifetime average exposure intensity from questionnaire information. We evaluated this algorithm against measured urinary pesticide concentrations for farmers who applied glyphosate (n = 48), 2,4-D (n = 34), or chlorpyrifos (n = 34).

Implications for epidemiologic research on variation by pesticide in studies of farmers and their families.

Epidemiologic studies rely on participants' recall to classify their exposure to specific pesticides. As exposure classification evolves, an important issue is whether the recall of pesticide application details can be used to derive measures of exposure intensity or cumulative exposure. A preliminary analysis of biomonitoring data for farmers before, during, and after a pesticide application suggests variation for different pesticides in the proportion with detectable urinary concentrations, urinary levels, and patterns of uptake and elimination.

Biomonitoring for farm families in the farm family exposure study.

Objectives: The Farm Family Exposure Study was conducted to evaluate real-world pesticide exposure for farmers, spouses, and children.

Methods: Eligible farm families from Minnesota and South Carolina were randomly selected from a roster of licensed private pesticide applicators. Eligibility required that the family include a farmer, spouse, and at least one child between the ages of 4 and 17 years, that the family live on the farm, that the farmer planned to apply one of the target pesticides [glyphosate, chlorpyrifos, 2,4-dichlorophenoxy acetic acid (2,4-D)] to at least 10 acres (4.

Glyphosate biomonitoring for farmers and their families: results from the Farm Family Exposure Study.

Glyphosate is the active ingredient in Roundup agricultural herbicides and other herbicide formulations that are widely used for agricultural, forestry, and residential weed control. As part of the Farm Family Exposure Study, we evaluated urinary glyphosate concentrations for 48 farmers, their spouses, and their 79 children (4-18 years of age). We evaluated 24-hr composite urine samples for each family member the day before, the day of, and for 3 days after a glyphosate application.

An analysis of glyphosate data from the California Environmental Protection Agency Pesticide Illness Surveillance Program.

Glyphosate is among the pesticides most frequently reported to the California EPA Pesticide Illness Surveillance Program. We analyzed glyphosate-related calls to the Pesticide Illness Surveillance Program in order to assess the number of reports involving systemic symptoms and to better understand the nature and severity of reported cases. Data on glyphosate and other pesticides are available for the years 1982-1997 including: type of exposure (agricultural/other); target organ(s) affected (skin/eye/respiratory/systemic); exposure(s); an assessment of causal relationship (possible, probable, or definite); and limited medical text.