Pesticides and childhood cancers.

To evaluate the possible association between pesticides and the risk of childhood cancers, epidemiologic studies published between 1970 and 1996 were critically reviewed. Thirty-one studies investigated whether occupational or residential exposure to pesticides by either parents or children was related to increased risk of childhood cancer. In general, the reported relative risk estimates were modest. Risk estimates appeared to be stronger when pesticide exposure was measured in more detail. Frequent occupational exposure to pesticides or home pesticide use was more strongly associated with both childhood leukemia and brain cancer than either professional exterminations or the use of garden pesticides. Occupational pesticide exposure was also associated with increased risk of Wilms' tumor, Ewing's sarcoma, and germ cell tumors. Residence on a farm, a proxy for pesticide exposure, was associated with increased risk of a number of childhood cancers. Although increased risk of some childhood cancers in association with pesticide exposure is suggested by multiple studies, methodological limitations common to many studies restrict conclusions; these include indirect exposure classification, small sample size, and potential biases in control selection. Opportunities for methodologic improvement in future studies of pesticides and childhood cancers are described

Joint modeling of survival time and longitudinal outcomes with flexible random effects

Joint models with shared Gaussian random effects have been conventionally used in analysis of longitudinal outcome and survival endpoint in biomedical or public health research. However, misspecifying the normality assumption of random effects can lead to serious bias in parameter estimation and future prediction. In this paper, we study joint models of general longitudinal outcomes and survival endpoint but allow the underlying distribution of shared random effect to be completely unknown. For inference, we propose to use a mixture of Gaussian distributions as an approximation to this unknown distribution and adopt an Expectation–Maximization (EM) algorithm for computation. Either AIC and BIC criteria are adopted for selecting the number of mixtures. We demonstrate the proposed method via a number of simulation studies. We illustrate our approach with the data from the Carolina Head and Neck Cancer Study (CHANCE)

Quantification of arsenic, lead, mercury and cadmium in newborn dried blood spots

AbstractExposures to heavy metals during fetal and perinatal development are of particular concern. Yet, the health impacts of exposures to toxic metals during these early stages of human development are not well understood due to the paucity of in vivo human data. Dried blood spots (DBS), collected by public health departments to screen for inherited metabolic errors and other disorders, are routinely archived and can be used for exposure assessment. Here we report an improved method for quantifying arsenic, lead, mercury and cadmium in newborn DBS to facilitate epidemiologic research on the health effects of early exposures to toxic metals

Insurance-Based Differences in Time to Diagnostic Follow-up after Positive Screening Mammography

Insurance may lengthen or inhibit time to follow-up after positive screening mammography. We assessed the association between insurance status and time to initial diagnostic follow-up after a positive screening mammogram

Use of antihistamine medications during early pregnancy and isolated major malformations

Antihistamines are commonly used during pregnancy. There is little evidence that they have teratogenic effects, but there are knowledge gaps with respect to newer products, as well as the relationship between specific antihistamines and specific birth defects

Adjuvant radiation therapy and health-related quality of life among older women with early-stage endometrial cancer: an analysis using the SEER-MHOS linkage

Purpose: Radiation therapy (RT) has been associated with decreased health-related quality of life (HRQOL) in clinical trials of early-stage endometrial cancer (EC), but few studies have examined the association in real-world settings. We assessed HRQOL associated with adjuvant RT for older women with early-stage EC within a large U.S. population-based registry resource. Methods: The Surveillance Epidemiology and End Results and the Medicare Health Outcomes Survey linkage (1998–2017) was used to identify women with early-stage EC aged ≥ 65 years at survey who received surgery and were diagnosed ≥ 1-year prior (n = 1,140). HRQOL was evaluated with the 36-item Short-Form Health Survey (SF-36) until 2006 and the Veterans RAND 12-Item Health Survey (VR-12) post 2006. Ordinary least squares regression was used to estimate mean difference (MD) in T scores and 95% confidence intervals (CIs) comparing treatment groups (surgery alone, adjuvant external beam radiation therapy [EBRT], or adjuvant vaginal brachytherapy [VBT]) after accounting for confounders using propensity score weighting. Results: Overall, RT was not associated with physical health (MD = 0.97; 95% CI = − 1.13, 3.07) or mental health (MD = − 0.78; 95% CI = − 2.60, 1.05) relative to surgery alone. In analyses by RT type, adjuvant VBT was associated with better general health on the SF-36/VR-12 subscale (MD = 3.59; 95% CI = 0.56, 6.62) relative to surgery alone. No statistically significant associations were observed for adjuvant VBT and physical or mental health, or for adjuvant EBRT and any HRQOL domain. Conclusion: Older women with early-stage EC treated with adjuvant RT did not report worse physical and mental HRQOL scores compared to those treated with surgery alone, though relevant symptoms should be evaluated further to fully understand the disease and treatment specific aspects of the HRQOL

Comparison of a Trial of Labor with an Elective Second Cesarean Section

BACKGROUND: In an attempt to reduce the rate of cesarean section, obstetricians now offer a trial of labor to pregnant women who have had a previous cesarean section. Although a trial of labor is usually successful and is relatively safe, few studies have directly addressed the maternal and perinatal morbidity and mortality associated with this method of delivery. METHODS: We performed a population-based, longitudinal study of 6138 women in Nova Scotia who had previously undergone cesarean section and had delivered a singleton live infant in the period from 1986 through 1992. RESULTS: A total of 3249 women elected a trial of labor, and 2889 women chose to undergo a second cesarean section. There were no maternal deaths. The overall rate of maternal morbidity was 8.1 percent; 1.3 percent had major complications (a need for hysterectomy, uterine rupture, or operative injury) and 6.9 percent had minor complications (puerperal fever, a need for blood transfusion, or abdominal-wound infection). Although the overall rate of maternal complications did not differ significantly between women who chose a trial of labor and the women who elected cesarean section (odds ratio for the trial-of-labor group, 0.9; 95 percent confidence interval, 0.8 to 1.1), major complications were nearly twice as likely among women undergoing a trial of labor (odds ratio, 1.8; 95 percent confidence interval, 1.1 to 3.0). Apgar scores, admission to the neonatal intensive care unit, and perinatal mortality were similar among the infants whose mothers had a trial of labor and those whose mothers underwent elective cesarean section. CONCLUSION: Among pregnant women who have had a cesarean section, major maternal complications are almost twice as likely among those whose deliveries are managed with a trial of labor as among those who undergo an elective second cesarean section

Patient characteristics and health system factors associated with adjuvant radiation therapy receipt in older women with early-stage endometrial cancer

Introduction: Among women with early-stage endometrial cancer (EC), age, stage, grade, and histology are used to determine fitness for adjuvant radiation therapy (RT) administration. We examined non-cancer factors associated with adjuvant RT receipt in older women with early-stage EC. Materials & methods: Using data from the Surveillance Epidemiology and End Results cancer registry program linked with Medicare claims, we identified 25,654 women (aged ≥66 years) diagnosed with first primary stage I-II EC during 2004–2017 who underwent a hysterectomy. Diagnosis and procedure codes were used to identify adjuvant RT claims filed for the seven-month period post-hysterectomy. Multivariable log-binomial regression was used to estimate adjuvant RT prevalence associated with patient characteristics and health system factors after adjustment for age, frailty, and endometrial factors. Results: Adjuvant RT was less commonly administered to Asian American and Pacific Islander patients than non-Hispanic White patients (Prevalence ratio [PR], 0.84; 95% confidence interval [CI], 0.73 to 0.97). Compared to women treated in the Northeast region, women treated other regions of the US were less likely to undergo adjuvant RT (PR, 0.75; 95% CI, 0.71 to 0.79). Residing in rural or high neighborhood-poverty counties was associated with lower adjuvant RT administration. Higher comorbidity score was not associated with reduced prevalence of adjuvant RT receipt; however, women with high probability of predicted probability of frailty were less likely to undergo adjuvant RT (PR, 0.67; 95% CI, 0.55 to 0.81) compared to women with low probability of frailty. Women who received lymph node assessment were more likely to undergo adjuvant RT compared to women who did not (PR, 1.43; 95% CI, 1.34 to 1.51). Women treated by a gynecologic oncologist were more likely to undergo adjuvant RT compared to women treated by a non-gynecologic oncologist (PR 1.09; 95% CI, 1.04 to 1.14). Adjuvant RT was more commonly administered to women treated in larger academic hospitals. Discussion: Findings suggest that various non-cancer factors affect the delivery of adjuvant RT to older women with early-stage EC in real-world oncology practice. Advancing our understanding of factors associated with adjuvant RT administration may help expand equitable access to RT

Falls, walking or balance problems, and limitations in activities of daily living (ADLs) among older endometrial cancer survivors

Purpose: Functional status deficits are important quality of life concerns for older cancer survivors. We examined the prevalence of falls, walking/balance problems, and limitations in activities of daily living (ADLs) among older women with a history of endometrial cancer. Methods: Cancer registry records from the Surveillance, Epidemiology, and End Results (SEER) program linked with Medicare Health Outcomes Survey (MHOS) data were used to identify endometrial cancer survivors aged ≥ 65 years who completed a survey ≥ 1 year after their cancer diagnosis (N = 3766), as well as an age- and race-matched group of women without a cancer history (N = 3766). We estimated prevalence ratios (PRs) to compare the prevalence of falls, walking or balance problems, and limitations in ADLs (bathing, dressing, eating, getting in/out of chairs, walking, using the toilet) between groups. Results: Difficulty with walking or balance was more common among survivors than the noncancer group (43% vs 36%; PR = 1.19; 95% CI: 1.10–1.27). Fall prevalence was similar between groups (endometrial cancer: 25%; noncancer: 26%; PR = 0.98; 95% CI: 0.89–1.08). Nearly half of endometrial cancer survivors (47%) reported at least one ADL limitation, with several activities (getting in/out of a chair, walking, bathing, using the toilet) more often limited among survivors than among women without cancer. Conclusion: Functional impairments, especially problems with walking and/or balance, are common among older endometrial cancer survivors. Our results highlight the importance of addressing functional problems during the ongoing survivorship care of women with a history of endometrial cancer, with referral to rehabilitation or other relevant services when indicated