Patterns of granulocyte colony-stimulating factor prophylaxis in patients with cancer receiving myelosuppressive chemotherapy.

PURPOSE: To evaluate patterns of primary prophylactic (PP) granulocyte colony-stimulating factor (G-CSF) use following chemotherapy by cancer type and febrile neutropenia (FN) risk. METHODS: Using a commercial administrative database, we identified adult patients diagnosed with breast, colorectal, lung, ovarian cancer, or non-Hodgkin lymphoma (NHL) who initiated chemotherapy with high risk (HR) or intermediate risk (IR) for FN between January 1, 2013, and August 31, 2017. We describe use of PP-G-CSF, proportion completing all their cycles with pegfilgrastim, timing of pegfilgrastim, and duration of short-acting G-CSF. RESULTS: Among 22,868 patients (breast 11,513; colorectal 3765; lung 4273; ovarian 1287; and NHL 2030), 36.8% received HR and 63.2% received IR (64.4% of whom had ≥ 1 risk factor [RF] for FN). Proportions of patients receiving PP-G-CSF in the first cycle were 76.1%, 28.2%, and 26.4% among patients receiving HR, IR, and IR plus ≥ 1 RF, respectively. Among breast cancer patients receiving HR regimens and initiating PP-pegfilgrastim, 60.4% (95% confidence interval [CI] 57.2-63.6%) initiating via on-body injector (OBI) and 51.9% (95% CI 48.0-55.8%) initiating via prefilled syringe (PFS) completed all their cycles with OBI and PFS, respectively. Among all cycles with PP-PFS, 8.5% received PFS on the same day as chemotherapy completion. Mean administrations/cycle were 3.2 (standard deviation [SD] 2.3) for filgrastim, 3.0 (SD 1.6) for filgrastim-sndz, and 4.3 (SD 2.5) for tbo-filgrastim. CONCLUSIONS: There is under- and mistimed use of PP-G-CSF among patients at HR for FN. Novel pegfilgrastim delivery devices could help breast cancer patients at HR for FN complete all their cycles with timely prophylaxis.

A Survey of Oncologists' Perceptions and Opinions Regarding the Use of Granulocyte Colony-Stimulating Factors.

The purpose of the study is to describe oncologists' perceptions and opinions about patient eligibility, guidelines, and barriers for use of granulocyte colony-stimulating factor (G-CSF), overall and stratified by their affiliation with the Oncology Care Model (OCM). In May 2018, we invited and recruited practicing US oncologists from a national database for an online survey. Level of agreement was identified using a seven-point scale, ranging from strongly disagree to strongly agree. Of 200 participating oncologists, 70 were OCM-affiliated. Overall, 65% of oncologists agreed or strongly agreed that all patients at high risk of febrile neutropenia (FN) should receive prophylactic G-CSF, and half agreed or strongly agreed that benefits of G-CSF outweigh the potential adverse effects. The most common barriers to G-CSF use for patients at high risk of FN included patient refusal (37.1% of OCM-affiliated oncologists vs. 21.5% of non-OCM-affiliated oncologists), not on protocol/not supported by guidelines (32.9% vs. 23.1%), lack of reimbursement to practice (30.0% vs. 15.4%), and concerns about insurance coverage (22.9% vs. 26.9%). More OCM-affiliated oncologists reported that their practices offer and strongly encourage adherence to a specific protocol for G-CSF use (49.2%) versus non-OCM oncologists (31.3%). Despite recommendations from national guidelines and strong evidence from randomized, controlled clinical trials, only two thirds of oncologists agree or strongly agree that all patients at high risk of FN should receive primary G-CSF prophylaxis. Decisions about G-CSF prophylaxis may be affected by factors other than risk of FN, such as patient choice, practice protocols/guidelines, lack of reimbursement, and insurance coverage.

Mesothelioma among Motor Vehicle Mechanics: An Updated Review and Meta-analysis.

BACKGROUND: We published a meta-analysis of the association between work as a motor vehicle mechanic and mesothelioma in 2004. Since then, several relevant studies on this topic have been published. Thus, to update the state-of-the-science on this issue, we conducted a new systematic review and meta-analysis. METHODS: A comprehensive PubMed literature search through May 2014 was conducted to identify studies that reported relative risk estimates for mesothelioma among motor vehicle mechanics (in general), and those who were engaged in brake repair (specifically). Studies were scored and classified based on study characteristics. Random-effects meta-analyses generated summary relative risk estimates (SRREs) and corresponding 95% confidence intervals (CI). Heterogeneity of results was examined by calculating Q-test P-values (P-H) and I (2) estimates. Sub-group and sensitivity analyses were conducted for relevant study characteristics and quality measures. RESULTS: Ten case-control studies, one cohort study, and five proportionate mortality ratio (PMR)/standardized mortality odds ratio (SMOR) studies were identified and included in the quantitative assessment. Most meta-analysis models produced SRREs below 1.0, and no statistically significant increases in mesothelioma were observed. The SRRE for all studies was 0.80 (95% CI: 0.61-1.05) with significant heterogeneity (P-H <0.001, I (2) = 62.90). A similar SRRE was observed among the five Tier 1 studies with the highest quality ratings (SRRE = 0.76, 95% CI: 0.46-1.25), with no heterogeneity among studies (P-H = 0.912, I (2) = 0.00). Meta-analysis of the Tier 2 (n = 5) and Tier 3 (n = 6) studies resulted in SRREs of 1.09 (95% CI: 0.76-1.58) and 0.73 (95% CI: 0.49-1.08), respectively. Restricting the analysis to Tiers 1 and 2 combined resulted in an SRRE of 0.92 (95% CI: 0.72-1.29). The SRRE specific to brake work (n = 4) was 0.64 (95% CI: 0.38-1.09). CONCLUSIONS: This meta-analysis of the epidemiologic studies provides evidence that motor vehicle mechanics, including workers who were engaged in brake repair, are not at an increased risk of mesothelioma.

Acute lymphoblastic leukemia: an assessment of international incidence, survival, and disease burden.

PURPOSE: Acute lymphoblastic leukemia (ALL) is a rare hematological malignancy. With the recent introduction of a classification system for hematopoietic and lymphoid neoplasms, more comprehensive assessment of ALL epidemiology is now possible. In this study, we describe recent international incidence of ALL and project the annual number of diagnoses to 2025. We also estimate relative survival and average potential years of life lost (AYLL) to assess the societal burden of ALL. METHODS: Age-specific incidence data for ALL from select cancer registries in different geographies were obtained from the International Agency for Research on Cancer's Cancer Incidence in Five Continents Database. Country-specific age-standardized rates were calculated to allow for direct comparisons between countries. ALL-specific mortality and relative survival data were only available from the United States (US) National Cancer Institute's Surveillance, Epidemiology, and End Results program; mortality rates were estimated for other countries. RESULTS: The age-standardized incidence rate of ALL during 2003-2007 ranged from 1.08 to 2.12 per 100,000 person-years in selected countries. Incidence was generally higher in the Americas and Oceania and lower in Asia and Eastern Europe. In most countries, the incidence rate of ALL in children was approximately four times that in adults. Survival was particularly poor among adults. In selected countries, the estimated AYLL ranged from 30 to 48 years for all ages and from 23 to 39 years for adults. CONCLUSIONS: Although a rare disease, ALL presents a significant public health burden given poor survival outcomes among adults, AYLL, and its importance as the most common pediatric cancer.

Prevalence and incidence of comorbidities in elderly women with ovarian cancer.

OBJECTIVE: Studies suggest comorbidity plays an important role in ovarian cancer. We characterized the epidemiology of comorbid conditions in elderly U.S. women with ovarian cancer. METHODS: Women with ovarian cancer age ≥66 years, and matched cancer-free women, were identified using the National Cancer Institute's Surveillance, Epidemiology, and End Results registry linked to Medicare claims. Prevalence before diagnosis/index date and 3- and 12-month incidence rates (per 1000 person-years) after diagnosis/index date were estimated for 34 chronic and acute conditions across a broad range of diagnostic categories. RESULTS: There were 5087 each of women with ovarian cancer and cancer-free women. The prevalence of most conditions was similar between cancer and cancer-free patients, but exceptions included hypertension (51.8% and 43.5%, respectively), osteoarthritis (13.4% and 17.3%, respectively), and cerebrovascular disease (8.0% and 9.8%, respectively). In contrast, 3- and 12-month incidence rates (per 1000 person years) of most conditions were significantly higher in cancer than in cancer-free patients: hypertension (177.3 and 47.4, respectively); thromboembolic event (145.3 and 5.5, respectively); congestive heart failure (113.3 and 28.6, respectively); infection (664.4 and 55.2, respectively); and anemia (408.3 and 33.1, respectively) at 12 months. CONCLUSIONS: Comorbidities were common among elderly women. After cancer diagnosis, women with ovarian cancer had a much higher incidence of comorbidities than cancer-free women. The high incidence of some of these comorbidities may be related to the cancer or its treatment, but others may have been prevalent but undiagnosed until the cancer diagnosis. The presence of comorbidities may affect treatment decisions.

Analysis of mobile phone design features affecting radiofrequency power absorbed in a human head phantom.

The US FCC mandates the testing of all mobile phones to demonstrate compliance with the rule requiring that the peak spatial SAR does not exceed the limit of 1.6 W/kg averaged over any 1 g of tissue. These test data, measured in phantoms with mobile phones operating at maximum antenna input power, permitted us to evaluate the variation in SARs across mobile phone design factors such as shape and antenna design, communication technology, and test date (over a 7-year period). Descriptive statistical summaries calculated for 850 MHz and 1900 MHz phones and ANOVA were used to evaluate the influence of the foregoing factors on SARs. Service technology accounted for the greatest variability in compliance test SARs that ranged from AMPS (highest) to CDMA, iDEN, TDMA, and GSM (lowest). However, the dominant factor for SARs during use is the time-averaged antenna input power, which may be much less than the maximum power used in testing. This factor is largely defined by the communication system; e.g., the GSM phone average output can be higher than CDMA by a factor of 100. Phone shape, antenna type, and orientation of a phone were found to be significant but only on the order of up to a factor of 2 (3 dB). The SAR in the tilt position was significantly smaller than for touch. The side of the head did not affect SAR levels significantly. Among the remaining factors, external antennae produced greater SARs than internal ones, and brick and clamshell phones produced greater SARs than slide phones. Assuming phone design and usage patterns do not change significantly over time, we have developed a normalization procedure and formula that permits reliable prediction of the relative SAR between various communication systems. This approach can be applied to improve exposure assessment in epidemiological research.

An evaluation of self-reported mobile phone use compared to billing records among a group of engineers and scientists.

Most epidemiologic studies of potential health impacts of mobile phones rely on self-reported information, which can lead to exposure misclassification. We compared self-reported questionnaire data among 60 participants, and phone billing records over a 3-year period (2002-2004). Phone usage information was compared by the calculation of the mean and median number of calls and duration of use, as well as correlation coefficients and associated P-values. Average call duration from self-reports was slightly lower than billing records (2.1 min vs. 2.8 min, P = 0.01). Participants reported a higher number of average daily calls than billing records (7.9 vs. 4.1, P = 0.002). Correlation coefficients for average minutes per day of mobile phone use and average number of calls per day were relatively high (R = 0.71 and 0.69, respectively, P < 0.001). Information reported at the monthly level tended to be more accurate than estimates of weekly or daily use. Our findings of modest correlations between self-reported mobile phone usage and billing records and substantial variability in recall are consistent with previous studies. However, the direction of over- and under-reporting was not consistent with previous research. We did not observe increased variability over longer periods of recall or a pattern of lower accuracy among older age groups compared with younger groups. Study limitations included a relatively small sample size, low participation rates, and potential limited generalizability. The variability within studies and non-uniformity across studies indicates that estimation of the frequency and duration of phone use by questionnaires should be supplemented with subscriber records whenever practical.

Occupational trichloroethylene exposure and kidney cancer: a meta-analysis.

BACKGROUND: We conducted a meta-analysis of occupational studies of trichloroethylene-exposed workers to evaluate patterns of associations by study design, exposure assessment methods, and occupational groups. METHODS: Estimates of summary relative risk (RR) were calculated using inverse-variance weighting methods. Cohort studies were classified as group I or group II, depending on quality of the study design and exposure assessment procedures. We conducted sensitivity analyses to examine sources of heterogeneity. RESULTS: Across all studies meeting our inclusion criteria (n = 23), the summary RR was 1.42 (95% confidence interval = 1.17-1.77), with heterogeneity present (test for heterogeneity: P = 0.001). After removal of 3 outlier studies, the summary RR for the remaining studies was 1.24 (1.06-1.45 (test for heterogeneity: P = 0.616)). The summary RR for studies of workers who were identified as more likely exposed to trichloroethylene (group I studies) was 1.34 (1.06-1.68). With outlier studies removed, the group II summary RR estimates for the cohort studies was 0.88 (0.58-1.33) and for the case-control studies was 1.33 (1.02-1.73). The summary RR for studies that used biomarkers to classify exposure (n = 3) was 1.02 (0.59-1.77) and for studies of aerospace/aircraft workers (n = 7) was 1.14 (0.84-1.57). CONCLUSIONS: Positive associations were observed across various study groups. However, considerations of unmeasured potential confounding, lack of quantitative exposure assessment and lack of exposure-response patterns limit epidemiologic insight into the role of trichloroethylene exposure and its potential causal association with kidney cancer.

Prevalence of RAS and BRAF mutations in metastatic colorectal cancer patients by tumor sidedness: A systematic review and meta-analysis.

Studies have shown that the prevalence of RAS and BRAF mutations may differ by tumor sidedness among metastatic colorectal cancer (mCRC) patients. Both mutation status and tumor sidedness may impact survival and disease progression and RAS mutation status has been shown to predict response to anti-epidermal growth factor receptor (EGFR) therapy. A systematic literature review and meta-analysis were conducted to estimate the pooled prevalence of RAS and BRAF mutations by tumor sidedness in studies of mCRC patients. Forty-four studies comprising 15 981 mCRC patients tested for RAS and/or BRAF mutations were included in the meta-analyses. The prevalence of RAS mutations differed significantly by tumor side (32.4% among left-sided tumors, 41.3% among right-sided tumors; P = .017), as did the prevalence of KRAS mutations (35.8% among left-sided tumors, 46.3% among right-sided tumors; P < .0001) and BRAF mutations (4.3% among left-sided tumors, 16.3% among right-sided tumors; P < .0001). Among right-sided tumors, the prevalence of RAS and KRAS mutations varied significantly by study design, with higher prevalence among observational studies than clinical trials, and there was significant variation by study location for the prevalence of KRAS mutations in left-sided tumors and the prevalence of BRAF mutations in right-sided tumors. These results help to better characterize the mCRC population to better inform clinicians and researchers. Few of the included studies reported overall or progression-free survival (PFS) by both tumor sidedness and mutation status. As both of these factors may have prognostic impact, future studies should consider evaluating survival by these variables.

Duration of short-acting granulocyte colony-stimulating factor for primary prophylaxis and risk of neutropenia-related hospitalization in older patients with cancer.

PURPOSE: Evaluate the relationship between duration of primary prophylactic short-acting granulocyte colony-stimulating factor (PP-sG-CSF) and risk of neutropenia-related hospitalization (NRH) in older patients receiving myelosuppressive chemotherapy. METHODS: Using the Medicare claims database, we conducted a nested case-control study in a cohort of patients aged ≥66 years with breast, colorectal, lung, ovarian, or prostate cancer, or non-Hodgkin lymphoma who initiated a first cycle of any myelosuppressive chemotherapy January 1, 2008-September 30, 2016, and received PP-sG-CSF. We matched up to four controls to each NRH case by age, cancer type, regimen febrile neutropenia (FN) risk category, and year using incidence density sampling. We used conditional logistic regression adjusted for race, sex, and modified Charlson comorbidity index (CCI) to estimate relative risk of NRH related to duration of PP-sG-CSF categorized as <5 and ≥ 5 days. RESULTS: Of 2148 patients receiving PP-sG-CSF, 108 (5%) experienced NRH in the first cycle. We matched 333 controls to 96 cases. Cases were similar to controls in mean age, tumor type, and intermediate/high-risk regimen, but were more likely to have CCI ≥5 and less likely to use PP-sG-CSF ≥5 days (31% vs. 39%). Adjusted ORs (95% CI) for NRH were 0.69 (0.40-1.19) for ≥5 vs. <5 days of PP-sG-CSF among patients receiving any myelosuppressive chemotherapy, 0.43 (0.21-0.89) for intermediate/high-risk regimen, and 0.42 (0.19-0.89) for any myelosuppressive chemotherapy with all agents given on cycle day one only. CONCLUSIONS: Among older patients with cancer who are receiving PP-sG-CSF, ≥5 days of use was associated with substantial reduction in NRH risk.

Variations in hospitalization and emergency department/observation stays using the oncology care model methodology in Medicare data.

OBJECTIVE: To assess variations in hospitalizations, emergency department/observational (ED/OB) stays not resulting in hospitalization, reasons for hospitalization, and hospitalization discharge destinations after chemotherapy, information not provided as part of Oncology Care Model (OCM) baseline data. METHODS: OCM methodology was applied to the Medicare 20% sample data to identify 6-month patient episodes triggered by chemotherapy in 2012-2015. Proportions of episodes with hospitalization or ED/OB stays, reasons for hospitalization, and discharge destinations were summarized. RESULTS: Of 485,186 6-month episodes for 255,229 patients in 13,823 practices, 25% of episodes led to ≥1 hospitalization (from 14% in breast cancer to 56% in acute leukemia), and 23% to ED/OB stays (from 18% in breast cancer to 36% in liver cancer). In 2995 practices with ≥20 total episodes, practice-level proportions of episodes with hospitalization ranged from 14% to 31% (20th-80th percentile) and with ED/OB stays from 17% to 29%. For all cancers combined, the most frequent reasons for hospitalization were infection (13%), anemia (7%), dehydration (5%), and congestive heart failure (3%); the most common discharge destinations were home (71%) followed by a skilled nursing facility (13%), death (6%), and hospice (5%). Reasons for hospitalization and discharge destinations varied by cancer type; acute leukemia episodes led to the highest rates of infection and anemia, and central nervous system tumor episodes to the highest proportions of death or hospice discharge. CONCLUSION: The variations in frequency of and reasons for hospitalization, ED/OB stays, and hospitalization discharge destinations across cancer types should be considered when evaluating OCM practice performance.

Cancer mortality and oil production in the Amazon Region of Ecuador, 1990-2005.

OBJECTIVES: To compare cancer mortality rates in Amazon cantons (counties) with and without long-term oil exploration and extraction activities. METHODS: Mortality (1990 through 2005) and population census (1990 and 2001) data for cantons in the provinces of the northern Amazon Region (Napo, Orellana, Sucumbios, and Pastaza), as well as the province with the capital city of Quito (Pichincha province) were obtained from the National Statistical Office of Ecuador, Instituto Nacional del Estadistica y Censos (INEC). Age- and sex-adjusted mortality rate ratios (RR) and 95% confidence intervals (CI) were estimated to evaluate total and cause-specific mortality in the study regions. RESULTS: Among Amazon cantons with long-term oil extraction, activities there was no evidence of increased rates of death from all causes (RR = 0.98; 95% CI = 0.95-1.01) or from overall cancer (RR = 0.82; 95% CI = 0.73-0.92), and relative risk estimates were also lower for most individual site-specific cancer deaths. Mortality rates in the Amazon provinces overall were significantly lower than those observed in Pichincha for all causes (RR = 0.82; 95% CI = 0.81-0.83), overall cancer (RR = 0.46; 95% CI = 0.43-0.49), and for all site-specific cancers. CONCLUSIONS: In regions with incomplete cancer registration, mortality data are one of the few sources of information for epidemiologic assessments. However, epidemiologic assessments in this region of Ecuador are limited by underreporting, exposure and disease misclassification, and study design limitations. Recognizing these limitations, our analyses of national mortality data of the Amazon Region in Ecuador does not provide evidence for an excess cancer risk in regions of the Amazon with long-term oil production. These findings were not consistent or supportive of earlier studies in this region that suggested increased cancer risks.

Factors that distinguish serious versus less severe strain and sprain injuries: an analysis of electric utility workers.

BACKGROUND: Occupational sprain and strain injuries are one of the most common types of nonfatal occupational injuries and a significant source of lost workdays. This study examines factors associated with severe work-related sprain/strain injuries to the back, shoulder, and knees. METHODS: A synthetic case-control study was performed (controls were selected from the same pool of utility workers as cases). Cases included all electric utility workers who had experienced a severe work-related sprain/strain injury to the back, knee, or shoulder. Primary controls were selected from all workers who had sustained a minor injury. Secondary controls were selected from employees with a minor sprain/strain injury to the back, knee, or shoulder. Multivariate logistic regression models were used to estimate odds ratios and 95% confidence intervals. RESULTS: Workers 41 years and older were more likely to have experienced severe shoulder sprain/strain injuries [Age 41-50: OR = 3.62, 95% CI: 1.71-7.65; age 51 and older: OR = 4.49, 95% CI: 1.89-10.67] and severe back sprain/strain injuries [Age 41-50: OR = 1.70, 95% CI: 1.06-2.33; age 51 and older: OR = 1.5, 95% CI: 0.90-2.52]. Line workers and maintenance workers had an increased risk of serious sprain/strain injuries. Gender and day of week were not significantly associated with sprain/strain injuries. DISCUSSION: Though this study is limited by available data, future studies may benefit from this preliminary examination of occupational and demographic characteristics associated with serious sprain/strain injuries among electric utility workers.

Low-level arsenic exposure in drinking water and bladder cancer: a review and meta-analysis.

Although exposure to high levels of arsenic in drinking water is associated with excess cancer risk (e.g., skin, bladder, and lung), lower exposures (e.g., <100-200 microg/L) generally are not. Lack of significant associations at lower exposures may be attributed to methodologic issues (e.g., inadequate statistical power, exposure misclassification), or to differences in the dose-response relationship at high versus low exposures. The objectives of this review and meta-analysis were to evaluate associations, examine heterogeneity across studies, address study design and sample size issues, and improve the precision of estimates. Eight studies of bladder cancer and low-level arsenic exposure met our inclusion criteria. Meta-analyses of never smokers produced summary relative risk estimates (SRREs) below 1.0 (highest versus lowest exposure). The SRRE for never and ever smokers combined was elevated slightly, but not significantly (1.11; 95% CI: 0.95-1.30). The SRRE was somewhat elevated among ever smokers (1.24; 95% CI: 0.99-1.56), and statistical significance was observed in some subgroup analyses; however, heterogeneity across studies was commonly present. Although uncertainties remain, low-level arsenic exposure alone did not appear to be a significant independent risk factor for bladder cancer. More studies with detailed smoking history will help resolve whether smoking is an effect modifier.

Estimating uncertainty in observational studies of associations between continuous variables: example of methylmercury and neuropsychological testing in children.

BACKGROUND: We suggest that the need to account for systematic error may explain the apparent lack of agreement among studies of maternal dietary methylmercury exposure and neuropsychological testing outcomes in children, a topic of ongoing debate. METHODS: These sensitivity analyses address the possible role of systematic error on reported associations between low-level prenatal exposure to methylmercury and neuropsychological test results in two well known, but apparently conflicting cohort studies: the Faroe Islands Study (FIS) and the Seychelles Child Development Study (SCDS). We estimated the potential impact of confounding, selection bias, and information bias on reported results in these studies using the Boston Naming Test (BNT) score as the outcome variable. RESULTS: Our findings indicate that, assuming various degrees of bias (in either direction) the corrected regression coefficients largely overlap. Thus, the reported effects in the two studies are not necessarily different from each other. CONCLUSION: Based on our sensitivity analysis results, it is not possible to draw definitive conclusions about the presence or absence of neurodevelopmental effects due to in utero methylmercury exposure at levels reported in the FIS and SCDS.

A nested case-control study of brain tumors among employees at a petroleum exploration and extraction research facility.

Work-related exposures potentially associated with a cluster of brain tumors at a petroleum exploration and extraction research facility were evaluated in a nested case-control study. Fifteen cases were identified in the original cohort and 150 matched controls were selected. Odds ratios (ORs) for occupational exposure to petroleum, radiation, solvents, magnetic fields, and work activities were near or below 1.0. ORs near 1.5 were observed for: working with computers (OR = 1.47; 95% confidence interval [CI] = 0.30-9.35); work-related travel (OR = 1.48; 95% CI = 0.25-5.95), and travel immunizations (OR = 1.62; 95% CI = 0.23-9.45). Higher ORs were observed for work in administrative and marketing buildings and for achieving a master's or higher degree (OR = 2.0, 95% CI = 0.4-10.7). While some ORs above 1.5 were noted, no work-related chemical and physical exposures were significantly associated with the occurrence of brain tumors among employees at this facility.

Thyroid function and perchlorate in drinking water: an evaluation among California newborns, 1998.

Perchlorate (ClO4-) has been detected in groundwater sources in numerous communities in California and other parts of the United States, raising concerns about potential impacts on health. For California communities where ClO4- was tested in 1997 and 1998, we evaluated the prevalence of primary congenital hypothyroidism (PCH) and high thyroid-stimulating hormone (TSH) levels among the 342,257 California newborns screened in 1998. We compared thyroid function results among newborns from 24 communities with average ClO4- concentrations in drinking water>5 microg/L (n=50,326) to newborns from 287 communities with average concentrations5 microg/L were observed, with 20.4 expected [adjusted prevalence odds ratio (POR)=0.71; 95% confidence interval (CI), 0.40-1.19]. Although only 36% of all California newborns were screened before 24 hr of age in 1998, nearly 80% of newborns with high TSH were screened before 24 hr of age. Because of the physiologic postnatal surge of TSH, the results for newborns screened before 24 hr were uninformative for assessing an environmental impact. For newborns screened>or=24 hr, the adjusted POR for high TSH was 0.73 (95% CI, 0.40-1.23). All adjusted odds ratios (ORs) were controlled for sex, ethnicity, birth weight, and multiple birth status. Using an assessment of ClO4- in drinking water based on available data, we did not observe an association between estimated average ClO4- concentrations>5 microg/L in drinking water supplies and the prevalence of clinically diagnosed PCH or high TSH concentrations.

Assessment of the beryllium lymphocyte proliferation test using statistical process control.

Despite more than 20 years of surveillance and epidemiologic studies using the beryllium blood lymphocyte proliferation test (BeBLPT) as a measure of beryllium sensitization (BeS) and as an aid for diagnosing subclinical chronic beryllium disease (CBD), improvements in specific understanding of the inhalation toxicology of CBD have been limited. Although epidemiologic data suggest that BeS and CBD risks vary by process/work activity, it has proven difficult to reach specific conclusions regarding the dose-response relationship between workplace beryllium exposure and BeS or subclinical CBD. One possible reason for this uncertainty could be misclassification of BeS resulting from variation in BeBLPT testing performance. The reliability of the BeBLPT, a biological assay that measures beryllium sensitization, is unknown. To assess the performance of four laboratories that conducted this test, we used data from a medical surveillance program that offered testing for beryllium sensitization with the BeBLPT. The study population was workers exposed to beryllium at various facilities over a 10-year period (1992-2001). Workers with abnormal results were offered diagnostic workups for CBD. Our analyses used a standard statistical technique, statistical process control (SPC), to evaluate test reliability. The study design involved a repeated measures analysis of BeBLPT results generated from the company-wide, longitudinal testing. Analytical methods included use of (1) statistical process control charts that examined temporal patterns of variation for the stimulation index, a measure of cell reactivity to beryllium; (2) correlation analysis that compared prior perceptions of BeBLPT instability to the statistical measures of test variation; and (3) assessment of the variation in the proportion of missing test results and how time periods with more missing data influenced SPC findings. During the period of this study, all laboratories displayed variation in test results that were beyond what would be expected due to chance alone. Patterns of test results suggested that variations were systematic. We conclude that laboratories performing the BeBLPT or other similar biological assays of immunological response could benefit from a statistical approach such as SPC to improve quality management.

Racial and Ethnic Variability in the Prevalence and Incidence of Comorbidities Associated with Gastric Cancer in the United States.

PURPOSE: Comorbidities are known to impact quality of life, treatment choices, and survival. Our objectives were to characterize comorbid conditions in a cohort of elderly gastric cancer patients and to determine if there is variability in the prevalence or incidence of the comorbid conditions across racial/ethnic groups. METHODS: A total of 12,612 individuals, ≥66 years of age, diagnosed with gastric cancer between 2000 and 2007, and an equal number of gender- and region-matched cancer-free individuals, were identified using the National Cancer Institute's Surveillance, Epidemiology, and End Results registry linked to Medicare claims in the United States. The prevalence (%) in the year before diagnosis and the 12-month incidence rates after diagnosis were estimated for 32 chronic and ten acute comorbid conditions for the entire cohort and by race/ethnicity (Asian, Black, Hispanic, White, and other) and Asian subgroups (e.g., Chinese, Filipino, Japanese, Pacific Islander). RESULTS: White and Black cases exhibited the highest prevalence of most comorbid conditions. Asian and Pacific Islander cases exhibited the lowest. There was substantial variability in the 12-month incidence of the comorbidities across the racial/ethnic groups. Electrolyte disorder was the most common incident condition among Whites and Blacks. With the exception of Whites, anemia was the most common incident condition in all racial and ethnic groups 180 days following chemotherapy. CONCLUSIONS: There is variability in the prevalence and incidence in comorbidities across racial/ethnic groups.