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Purpose To examine the feasibility of saccadic vector optokinetic perimetry (SVOP), an automated eye tracking perimeter, as a tool for visual field (VF) assessment in infants. Methods Thirteen healthy infants aged between 3.5 and 12.0 months were tested binocularly using an adapted SVOP protocol. SVOP uses eye tracking technology to measure gaze responses to stimuli presented on a computer screen. Modifications of SVOP for testing infants included adjusting the fixation target to display a short animation, increasing the stimulus size to equivalent to Goldmann V, and introducing a tiered test pattern strategy. Binocular, single-quadrant confrontation VF testing and Keeler preferential looking cards visual acuity testing was also performed. Results Using multiple test attempts when required, all but the youngest infant (12 of 13 [92.3%]) successfully completed a 4-point screening test. Seven infants (53.8%) successfully completed the 12-point test, four (30.8%) successfully completed the 20-point test, and three (23.1%) successfully completed the 40-point test. The effect of multiple test attempts and the complexity of the test pattern (number of test points) on performance was investigated, including test completion rate, percentage of correctly seen stimuli, and average time per tested stimulus. Conclusions The modified SVOP test strategy allowed successful assessment of binocular VFs in healthy infants. Future data collection from larger cohorts of infants is needed to derive normative limits of detection and assess accuracy in detecting and monitoring infant VF abnormalities. Translational relevance Eye tracking perimetry may provide a useful method of automated VF assessment in infants.

PRECIS Normal age-corrected threshold sensitivity values were determined for a new eye tracking perimeter and compared with standard automated perimetry (SAP). PURPOSE The purpose of this study was to determine threshold visual field sensitivities in normal subjects performing saccadic vector optokinetic perimetry (SVOP), a new eye tracking perimeter. PATIENTS AND METHODS A total of 113 healthy participants performed SVOP and SAP in both eyes with the order of testing randomized. The relationship between SAP and SVOP sensitivity was examined using Bland-Altman plots and 95% limits of agreement. The relationship between sensitivity and age was examined by pointwise linear regression and age-corrected normal threshold sensitivities were calculated. RESULTS After excluding unreliable tests, 97 participants with a mean age of 65.9±10.1 years were included. Average SAP mean deviation was -0.87±1.56 dB, SAP sensitivity was 29.20±1.68 dB and SVOP sensitivity was 32.18±1.96 dB. SVOP had a longer test duration (431±110 compared with 307±42 seconds for SAP, P

Background To examine the speed and accuracy of saccadic eye movements during a novel eye tracking threshold visual field assessment and determine whether eye movement parameters may improve ability to detect glaucoma. Methods A prospective study including both eyes of 31 patients with glaucoma and 23 controls. Standard automated perimetry (SAP) and eye tracking perimetry (saccadic vector optokinetic perimetry, SVOP) was performed. SVOP provided data on threshold sensitivity, saccade latency, and two measures of accuracy of saccades (direction bias and amplitude bias). The relationship between eye movement parameters and severity of glaucoma was examined and Receiver Operating Characteristic curves were used to assess ability to detect glaucoma. Results Patients with glaucoma had significantly slower saccades (602.9 ± 50.0 ms versus 578.3 ± 44.6 ms for controls, P = 0.009) and reduced saccade accuracy (direction bias = 7.4 ± 1.8 versus 6.5 ± 1.5 degrees, P = 0.006). There was a significant slowing of saccades and saccades became less accurate with worsening SAP sensitivity. Slower saccades were associated with increased odds of glaucoma; however, the AUC for saccade latency was only 0.635 compared to 0.914 for SVOP sensitivity. Conclusion Patients with glaucoma had significant differences in eye movements compared to healthy subjects, with a relationship between slower and less accurate eye movements and worse glaucoma severity. However, in a multivariable model, eye movement parameters were not of additional benefit in differentiating eyes with glaucoma from healthy controls.

To explore the feasibility of using Saccadic Vector Optokinetic Perimetry (SVOP) to differentiate glaucomatous and healthy eyes. A prospective case–control study was performed using a convenience sample recruited from a single university glaucoma clinic and a group of healthy controls. SVOP and standard automated perimetry (SAP) was performed with testing order randomised. The reference standard was a diagnosis of glaucoma based a comprehensive ophthalmic examination and abnormality on standard automated perimetry (SAP). The index test was SVOP. 31 patients with glaucoma and 24 healthy subjects were included. Mean SAP mean deviation (MD) in those with glaucoma was − 8.7 ± 7.4 dB, with mean SAP and SVOP sensitivities of 23.3 ± 0.9 dB and 22.1 ± 4.3 dB respectively. Participants with glaucoma were significantly older. On average, SAP sensitivity was 1.2 ± 1.4 dB higher than SVOP (95% limits of agreement = − 1.6 to 4.0 dB). SVOP sensitivity had good ability to differentiate healthy and glaucomatous eyes with a 95% CI for area under the curve (AUC) of 0.84 to 0.96, similar to the performance of SAP sensitivity (95% CI 0.86 to 0.97, P = 0.60). For 80% specificity, SVOP had a 95% CI sensitivity of 75.7% to 94.8% compared to 77.8% to 96.0% for SAP. SVOP took considerably longer to perform (514 ± 54 s compared to 267 ± 76 s for SAP). Eye tracking perimetry may be useful for detection of glaucoma but further studies are needed to evaluate SVOP within its intended sphere of use, using an appropriate design and independent reference standard.

ObjectivesPreterm births (PTBs) represent significant health risks, and several studies have found associations between high outdoor temperatures and PTB. We estimated both the total and natural direct effects (independent of particulate matter, ozone and nitrogen dioxide air pollutants) of the prior 2-day mean apparent temperature (AT) on PTB. We evaluated effect modification by maternal age, race, education, smoking status and prenatal care.Design and settingWe obtained birth records and meteorological data for the Detroit, Michigan, USA area, for the warm months (May to September), 1991 to 2001. We used a time series Poisson regression with splines of AT, wind speed, solar radiation and citywide average precipitation to estimate total effects. To accommodate multiple mediators and exposure-mediator interactions, AT inverse odds weights, predicted by meteorological and air pollutant covariates, were added in a subsequent model to estimate direct effects.ResultsAt 24.9°C relative to 18.6°C, 10.6% (95% CI: 3.8% to 17.2%) of PTBs were attributable to the total effects of AT, and 10.4% (95% CI: 2.2% to 17.5%) to direct effects. Relative excess risks of interaction indicated that the risk of PTB with increasing temperature above 18.6°C was significantly lower among black mothers and higher among mothers less than 19, older than 30, with late or no prenatal care and who smoked.ConclusionThis additional evidence of a direct association between high temperature and PTB may motivate public health interventions to reduce extreme heat exposures among pregnant women, particularly among those who may have enhanced vulnerability.

Cold and hot weather are associated with mortality and morbidity. Although the burden of temperature-associated mortality may shift towards high temperatures in the future, cold temperatures may represent a greater current-day problem in temperate cities. Hot and cold temperature vulnerabilities may coincide across several personal and neighborhood characteristics, suggesting opportunities for increasing present and future resilience to extreme temperatures. We present a narrative literature review encompassing the epidemiology of cold- and heat-related mortality and morbidity, related physiologic and environmental mechanisms, and municipal responses for hot and cold weather, illustrated by Detroit, Michigan, USA, a financially-burdened city in an economically diverse metropolitan area. The Detroit area experiences sharp increases in mortality and hospitalizations with extreme heat, while cold temperatures are associated with more gradual increases in mortality, with no clear threshold. Interventions, such as heating and cooling centers, may reduce but not eliminate temperature-associated health problems. Furthermore, direct hemodynamic responses to cold, sudden exertion, indoor air quality and respiratory epidemics likely contribute to cold-related mortality. Short- and long-term interventions to enhance energy and housing security and housing quality may reduce temperature-related health problems. Extreme temperatures can increase morbidity and mortality in municipalities like Detroit that experience both extreme heat and prolonged cold seasons amidst large socioeconomic disparities. The similarities in physiological and built environment vulnerabilities to both hot and cold weather suggest prioritization of strategies that address both present-day cold and near-future heat concerns.

Background Extreme heat (EH) and extreme precipitation (EP) events are expected to increase with climate change in many parts of the world. Characterizing the potential future morbidity and mortality burden of EH and EP and associated costs, as well as uncertainties in the estimates, can identify areas for public health intervention and inform adaptation strategies. We demonstrate a burden of disease and uncertainty assessment using data from Michigan, USA, and provide approaches for deriving these estimates for locations lacking certain data inputs. Methods Case-crossover analysis adapted from previous Michigan-specific modeling was used to characterize the historical EH-mortality relationship by county poverty rate and age group. Historical EH-associated hospitalization and emergency room visit risks from the literature were adapted to Michigan. In the U.S. Environmental Protection Agency’s BenMAP software, we used a novel approach, with multiple spatially-varying exposures, to estimate all non-accidental mortality and morbidity occurring on EH days (EH days; days where maximum temperature 32.2–35 C or > 35 C) and EP days. We did so for two time periods: the “historical” period (1971–2000), and the “projected” period (2041–2070), by county. Results The rate of all non-accidental mortality associated with EH days increased from 0.46/100,000 persons historically to 2.9/100,000 in the projected period, for 240 EH-attributable deaths annually. EH-associated ED visits increased from 12/100,000 persons to 68/100,000 persons, for 7800 EH-attributable emergency department visits. EP-associated ED visits increased minimally from 1.7 to 1.9/100,000 persons. Mortality and morbidity were highest among those aged 65+ (91% of all deaths). Projected health costs are dominated by EH-associated mortality ($280 million) and EH-associated emergency department visits ($14 million). A variety of sources contribute to a moderate-to-high degree of uncertainty around the point estimates, including uncertainty in the magnitude of climate change, population composition, baseline health rates, and exposure-response estimates. Conclusions The approach applied here showed that health burden due to climate may significantly rise for all Michigan counties by midcentury. The costs to health care and uncertainties in the estimates, given the potential for substantial attributable burden, provide additional information to guide adaptation measures for EH and EP. Electronic supplementary material The online version of this article (10.1186/s12940-019-0483-5) contains supplementary material, which is available to authorized users.

With climate change, extreme heat (EH) events are increasing, so it is important to understand who is vulnerable to heat-associated morbidity. We determined the association between EH and hospitalizations for all natural causes; cardiovascular, respiratory, and renal diseases; diabetes mellitus; and acute myocardial infarction in Michigan, USA, at different intensities and durations. We assessed confounding by ozone and how individual characteristics and health insurance payer (a proxy for income) modified these associations. We obtained Michigan Inpatient Database, National Climatic Data Center, and US Environmental Protection Agency ozone data for May-September, 2000-2009 for three Michigan counties. We employed a case-crossover design and modeled EH as an indicator for temperature above the 95th, 97th, or 99th percentile thresholds for 1, 2, 3, or 4 days. We examined effect modification by patient age, race, sex, and health insurance payer and pooled the county results. Among non-whites, the pooled odds ratio for hospitalization on EH (97th percentile threshold) vs. non-EH days for renal diseases was 1.37 (95 % CI = 1.13-1.66), which increased with increasing EH intensity, but was null among whites (OR = 1.00, 95 % CI = 0.81, 1.25). We observed a null association between EH and cardiovascular hospitalization. EH (99th percentile threshold) was associated with myocardial infarction hospitalizations. Confounding by ozone was minimal. EH was associated with hospitalizations for renal disease among non-whites. This information on vulnerability to heat-associated morbidity helps characterize the public health burden of EH and target interventions including patient education.

In this updated follow-up, we investigated the breast cancer experience among women in Michigan exposed to brominated flame retardants, some 30 years following exposure. Michigan residents were enrolled in a study cohort after exposure to polybrominated biphenyls (PBBs) through the consumption of contaminated food products. PBB concentrations were measured in serum at the time of enrolment. Cancer experience was determined by linkage to the Michigan Cancer Registry. We conducted a nested case–control study that included 51 women diagnosed with breast cancer during 1974–2004 and 202 age-matched controls. While the data suggest an increase in breast cancer risk with higher PBB exposure, this did not reach statistical significance. The OR of having breast cancer among women with PBB concentrations ≥10 ng/mL compared to women with PBB concentrations at or below the limit of detection of 1 ng/mL was 2.60, 95% CI 0.93 to 7.27, (p=0.07), when adjusted for age and family history of cancer in a first-degree female relative. It remains important to examine exposure to brominated chemicals and possible health effects, and to continue following the cancer experience of participants in this study.

Introduction: Preterm births (PTBs) cause significant infant health risks, and several studies have found associations between high temperatures and PTB. To understand this association in Detroit, ...

Purpose We evaluated threshold saccadic vector optokinetic perimetry (SVOP) and compared results to standard automated perimetry (SAP). Methods A cross-sectional study was done including 162 subjects (103 with glaucoma and 59 healthy subjects) recruited at a university hospital. All subjects underwent SAP and threshold SVOP. SVOP uses an eye tracker to monitor eye movement responses to stimuli and determines if stimuli have been perceived based on the vector of the gaze response. The test pattern used was equivalent to SAP 24-2 and stimuli were presented at Goldmann III. Average and pointwise sensitivity values obtained from both tests were compared using Pearson's correlation coefficient. Two versions of SVOP were evaluated. Results A total of 124 tests were performed with SAP and SVOP version 2. There was excellent agreement between mean threshold values obtained using SVOP and SAP (r = 0.95, P < 0.001). Excluding the blind spot, correlation between SVOP and SAP individual test point sensitivity ranged from 0.61 to 0.90, with 48 of 54 (89%) test points > 0.70. Overall SVOP showed good repeatability with a Pearson correlation of 0.88. The repeatability on a point-by-point basis ranged from 0.66 to 0.98, with 45 of 54 points (83%) > 0.80. Repeatability of SAP was 0.87, ranging from 0.69 to 0.96, with 47 of 54 (87%) points > 0.80. Conclusion Eye-tracking perimetry is repeatable and compares well with the current gold standard of SAP. The technique has advantages over conventional perimetry and could be useful for evaluating glaucomatous visual field loss, particularly in patients who may struggle with conventional perimetry. Translational Relevance Suprathreshold SVOP already is in the field. To our knowledge, this is the first report of threshold SVOP and provides a benchmark for future iterations.

Neonatal withdrawal syndrome, which is associated most frequently with opioid use in pregnancy, is an emerging public health concern, with recent studies documenting an increase in the rate of U.S. infants diagnosed.This study examined neonatal withdrawal syndrome diagnosis among Michigan infants from 2000 to 2009 and hospital length of stay (LOS) between infants with and without the syndrome for a subset of years (2006-2009).Michigan live birth records from 2000 to 2009 were linked with hospital discharge data to identify infants with neonatal withdrawal syndrome. Linked data were restricted to infants born between 2006 and 2009 to examine the difference in hospital LOS between infants with and without the syndrome. Multivariable regression models were constructed to examine the adjusted impact of syndrome diagnosis on infant LOS and fit using negative binomial distribution. Data were analyzed from July 2011 to February 2012.From 2000 to 2009, the overall birth rate of infants with neonatal withdrawal syndrome increased from 41.2 to 289.0 per 100,000 live births (p0.0001). Among infants born from 2006 to 2009, the average hospital LOS for those with the syndrome was between 1.36 (95% CI=1.24, 1.49) and 5.75 (95% CI=5.41, 6.10) times longer than for infants without it.Diagnosis of neonatal withdrawal syndrome increased significantly in Michigan with infants who had the syndrome requiring a significantly longer LOS compared to those without it.

Thyroid hormones, which influence body metabolism and development, could be affected by persistent organic pollutants. We sought to examine the relationship between polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) and thyroid disease. We employed incidence density sampling to perform a nested case control analysis of the Michigan Long-Term PBB Cohort. Cohort members (n=3333) were exposed to PBBs through contaminated cattle feed in 1973-1974 and to PCBs through daily life. Those with detectable serum PBB and PCB concentrations at enrollment were categorized into tertiles of PBB and PCB exposure. Case-patients were cohort members answering "Yes" to "Has a healthcare provider ever told you that you had a thyroid problem?" during follow-up interviews; control-patients were cohort members answering "No". We used odds ratios (OR) with 95% confidence intervals (CI) to compare odds of thyroid disease by PBB and PCB exposure and by various risk factors. Total cumulative thyroid disease incidence after 33 years was 13.9% among women and 2.6% among men. After adjusting for body mass index, we found no statistically significant differences in odds of any type of thyroid disease among women or men with elevated PBB or PCB exposure. Compared to control-patients, women with thyroid disease had increased odds of being overweight/obese (OR=2.82, 95% CI: 1.94-4.11) and developing infertility (OR=1.71, 95% CI: 1.08-2.69), diabetes (OR=1.61, 95% CI: 1.04-2.51), or arthritis (OR=1.71, 95% CI: 1.18-2.50) during follow-up. Additional research should explore potential associations between PBBs/PCBs and thyroid disease among children exposed in utero.

Background The upward trend in industrial nations in the incidence of male genitourinary (GU) conditions may be attributed to increased exposure to endocrine disruptors. Polybrominated biphenyl (PBB), a brominated flame retardant, is one such suspected endocrine disruptor. Objective We investigated the relationship between maternal serum levels of PBBs and GU conditions among male offspring exposed in utero. Methods In this cohort study of sons born to women accidentally exposed to PBBs during 1973–1974, we examined self-reported data on GU conditions among male offspring in relation to maternal serum PBB levels. We used generalized estimating equations to calculate odds ratios (ORs), controlling for gestational age at birth. Results Of 464 sons, 33 reported any GU condition (13 hernias, 10 hydroceles, 9 cryptorchidism, 5 hypospadias, and 1 varicocele). Four reported both hernia and hydrocele, and one both hernia and cryptorchidism. After adjustment for gestational age at birth, sons of highly exposed women (> 5 ppb) were twice as likely to report any GU condition compared with sons of the least exposed women [≤1 ppb; OR = 2.0; 95% confidence interval (CI), 0.8–5.1]. This risk was increased when we excluded sons born after the exposure but before the mother’s serum PBB measurement (OR = 3.1; 95% CI, 1.0–9.1). We found evidence of a 3-fold increase in reported hernia or hydrocele among sons with higher PBB exposure (test of trend p-value = 0.04). Neither hypospadias nor cryptorchidism was individually associated with PBB exposure. Conclusions Although cryptorchidism and hypospadias were not associated with in utero PBB exposure, this study suggests that other GU conditions may be associated with exposure to endocrine-disrupting chemicals during development.

To the Editor: We would like to comment on the article entitled “The influence of age at exposure to PBBs on birth outcomes” (Sweeney and Symanski, 2007, doi:10.1016/j.envres.2007.03.006). We have analyzed a mostly overlapping dataset described in our recently published article, “Maternal exposure to polybrominated and polychlorinated biphenyls: Infant birth weight and gestational age” (Givens et al., 2007). In brief, our sample included 899 infant birth records from 1975–1997 from women in the Michigan Long–Term Polybrominated Biphenyl (PBB) Study who also participated in the 1997–1998 Michigan Female Health Study telephone interview. The study population in Sweeney and Symanski (2007) included a total of 1,111 infant birth records from 1975–1994 from the Michigan Long–Term PBB Study cohort and a smaller cohort, the PCB Silo Cohort. Birth weight and gestational age were analyzed as separate outcomes in mixed–effects models in both articles; however, we found results that differed from Sweeney and Symanski (2007). Our birth weight model (Givens et al., Table 2, 2007) included similar covariates to Sweeney and Symanski’s (2007) model presented in Table 4 (gestational age, maternal age at infant’s birth, PBB, PCB, parity, and infant gender) and a few additional covariates (maternal smoking status and decade of infant’s birth). In comparison to Sweeney and Symanski’s (2007) model, we did not include maternal age at enrollment, interval between blood test (taken at enrollment) and date of infant’s birth, maternal BMI at enrollment, prenatal care and paternal education. Table 2 Collinearity Diagnostics - Principal Components Analysis^ Because our published results were contrary to Sweeney and Symanski’s (2007) results, we have attempted to replicate Sweeney and Symanski’s (2007) findings by including the additional variables of interval and maternal age at enrollment. Although our sample and methodological approaches are somewhat different, we were successfully able to reproduce similar parameter estimates as those presented in Sweeney and Symanski’s (2007) Table 4 (Table 1). Specifically, we were able to reproduce the association of maternal age at enrollment ≤ 10 years with approximately a 200 g heavier birth weight. However, we would like to raise several concerns with the interpretation of this result. The overall conclusion of a “maternal age at exposure” effect does not appear to be substantiated from the data for the following reasons: 1) “maternal age at enrollment” was used as a proxy for “maternal age at exposure,” without considering the potential error introduced by this proxy, 2) a substantial proportion of the population did not have detectable serum PBB in the blood, but Sweeney and Symanski’s (2007) models did not account for this, and 3) there are methodological issues that appear to be the source of the “maternal age at exposure” effect. Table 1 Mixed Models for Infant Birth Weight

The Michigan Long-Term PBB Study was established following exposure to polybrominated biphenyls (PBBs) in the early 1970s. Serum samples from cohort members were analyzed for PBB during 1976–1993. More than 20 years following this industrial incident, some participants still had measurable serum PBB concentration levels. Thus, there is continuing interest in understanding the elimination of PBB from the body. In the present study, we estimated serum PBB decay and investigated the effects of covariates on serum PBB decay rates among 406 female cohort members. We developed a decay model using a general linear mixed model, which attributes unique intercept and slope estimates for each individual while borrowing information across individuals for predicting these quantities. Age at exposure and body mass index (BMI) at the initial measurement were time-independent covariates. Time since exposure, smoking history, pregnancy status, and breast-feeding status were time-dependent covariates. Higher BMI was associated with a slower decay rate; smokers had a faster decay rate than nonsmokers; and increasing age at exposure was marginally associated with a slower decay rate. Our results suggest a faster serum PBB decay rate for women who breast-fed during the interval between serum PBB measurements. To evaluate the predictive performance of our modeling approach, we compared the results from this model with those from a previously developed ordinary least squares (OLS) two-stage decay model. The mixed-effects decay model predicted the observed serum PBB concentration levels significantly better than the OLS two-stage decay model (mixed-effects model, r=0.93; OLS two-stage model, r=0.86; P

Understanding the influence of maternal exposures on gestational age and birth weight is essential given that pre-term and/or low birth weight infants are at risk for increased mortality and morbidity. We performed a retrospective analysis of a cohort exposed to polybrominated biphenyls (PBB) through accidental contamination of cattle feed and polychlorinated biphenyls (PCB) through residual contamination in the geographic region. Our study population consisted of 444 mothers and their 899 infants born between 1975 and 1997. Using restricted maximum likelihood estimation, no significant association was found between estimated maternal serum PBB at conception or enrollment PCB levels and gestational age or infant birth weight in unadjusted models or in models that adjusted for maternal age, smoking, parity, infant gender, and decade of birth. For enrollment maternal serum PBB, no association was observed for gestational age. However, a negative association with high levels of enrollment maternal serum PBB and birth weight was suggested. We also examined the birth weight and gestational age among offspring of women with the highest (10%) PBB or PCB exposure, and observed no significant association. Because brominated compounds are currently used in consumer products and therefore, are increasingly prevalent in the environment, additional research is needed to better understand the potential relationship between in utero exposure to brominated compounds and adverse health outcomes.

Background Livestock farmers are more likely to be exposed to a variety of different farming hazards than crop farmers. An analysis of occupation and industry-coded U.S. death certificate data from 26 states for the years 1984–1993 was conducted to evaluate mortality patterns among crop and livestock farmers. Methods Cause-specific proportionate mortality ratios (PMRs) were calculated using a National Institute for Occupational Safety and Health (NIOSH) computer program designed to calculate sex and race specific PMRs for occupations and industries in population-based data. Results Among white male (WM) livestock farmers, there was a significantly higher mortality from cancer of the pancreas, prostate and brain, non-Hodgkin's lymphoma (NHL), multiple myeloma, acute and chronic lymphoid leukemia, and Parkinson's disease. WM crop farmers showed significantly higher mortality risk for cancer of the lip, skin, multiple myeloma, and chronic lymphoid leukemia. Conclusions These disease trends suggested that livestock farmers might be exposed to more carcinogens or agricultural chemicals than crop farmers. Am. J. Ind. Med. 42:410–420, 2002. Published 2002 Wiley-Liss, Inc.

Background National estimates of tendinitis and related disorders of the distal upper extremity among U.S. workers have not been available with the exception of carpal tunnel syndrome. Methods The Occupational Health Supplement Data of the 1988 National Health Interview Survey were analyzed for tendinitis and related disorders of the hand/wrist and elbow (distal upper extremity) using the Survey Data Analysis (SUDAAN) software. Results Among the 30,074 respondents (statistically weighted population of 127 million) who had worked anytime during the previous 12 months, 0.46% (95% CI: 0.36, 0.56) reported that they experienced a “prolonged” hand discomfort which was called tendinitis, synovitis, tenosynovitis, deQuervain's disease, epicondylitis, ganglion cyst, or trigger finger, by a medical person. This corresponds to 588,000 persons (95% CI: 457,000; 712,000) reporting one of these disorders, 28% (or 164,000) of which were thought to be work-related by the medical person. Among various risk factors examined by multiple logistic regression analysis, bending/twisting of the hands/wrists at work and female gender were significantly associated with reporting of these disorders. Conclusions By combining these cases with the previously reported cases of work-related carpal tunnel syndrome, we estimate that there were approximately 520,000 cases of work-related musculoskeletal disorders of the distal upper extremity among US workers in 1988. Am. J. Ind. Med. 39:328–335, 2001. Published 2001 Wiley-Liss, Inc.

The accurate assessment of visual field function can provide valuable information on a range of visual disorders. Saccadic Vector Optokinetic Perimetry (SVOP) is a novel instrument for measuring supra-threshold visual fields in young children who are otherwise unable to perform Automated Static Perimetry (ASP). However, limitations in Liquid Crystal Display (LCD) technology restrict the ability of SVOP to determine threshold values at various points in the visual field, often required in detailed perimetry examinations. This paper introduces a purpose-specific LCD luminance non-uniformity compensation approach to address this limitation. Thorough quantitative evaluation identifies the effectiveness of the proposed approach in (i) compensating for luminance non-uniformities across an LCD, and (ii) enabling SVOP to perform accurate and precise threshold visual field tests. The findings demonstrate that SVOP provides a promising alternative to the current threshold ASP standard (Humphrey Field Analyser).

Perimetry is essential for identifying visual field defects due to disorders of the eye and brain. However, young children are often unable to reliably perform the preferred method of visual field assessment known as automated static perimetry (ASP). This paper introduces a novel method of ASP specifically developed for children called Saccadic Vector Optokinetic Perimetry (SVOP). SVOP uses eye tracking to detect the natural saccadic eye response of gaze orientation towards visual field stimuli if they are seen. In this paper, the direction and magnitude of a sample of subject gaze responses to visual field stimuli is used to construct a software decision algorithm for use in SVOP. SVOP was clinically evaluated in a group of 24 subjects, comprising children and adults, with and without visual field defects, by comparison with an equivalent test on the Humphrey Field Analyser (HFA). SVOP provides promising visual field test results when compared with the reference HFA test, and has proven extremely useful in detecting visual field defects in children unable to perform traditional ASP.

Back pain accounts for about one fourth of workers' compensation claims in the United States. The Occupational Health Supplement to the 1988 National Health Interview Survey provided an opportunity to assess the scope of this problem. The 30,074 respondents who worked in the 12 months before the interview were defined as "workers", and those with back pain every day for a week or more during that period were defined as "cases." A weighting factor was applied to the answers to derive national estimates. In 1988, about 22.4 million back pain cases (prevalence 17.6%) were responsible for 149.1 million lost workdays; 65% of cases were attributable to occupational activities. For back pain attributed to activities at work, the risk was highest for construction laborers among males (prevalence 22.6%) and nursing aides among females (18.8%). Our analyses show that back pain is a major cause of morbidity and lost production for U.S. workers and identifies previously unrecognized high risk occupations, such as carpenters, automobile mechanics, maids, janitors, and hairdressers, for future research and prevention.

OBJECTIVES. The purpose of the study was to provide the health care and public health communities with national prevalence estimates of selected conditions in the US working population. METHODS. National prevalence estimates of self-reported conditions among working people were calculated from data collected for the 1988 Occupational Health Supplement to the National Health Interview Survey. RESULTS. The highest prevalence estimates were found among occupational groups. For example, the prevalence of back pain due to an injury at work among truck drivers was 6.7%; back pain due to repeated activities at work among mechanics and repairers of heavy equipment and machinery was 10.5%; hand discomfort among operators of machines that process metal, plastic, stone, and glass was 23.5%; and dermatitis due to contact with substances at work among physicians, dentists, nurses, pharmacists, and dietitians was 5.6%. CONCLUSIONS. A substantial proportion of these conditions among occupational groups with the highest prevalence estimates are occupational in origin. These prevalence estimates identify occupations in which efforts are needed to prevent these conditions.

This study examined a possible association of dietary exposure to polybrominated biphenyls (PBBs), a brominated flame retardant, and self-reported abnormal Pap test results and cervical dysplasia as a precursor to cervical cancer.Women in Michigan who ingested contaminated poultry, beef, and dairy products in the early 1970s were enrolled in a population-based cohort study in Michigan. Serum PBB and serum polychlorinated biphenyl (PCB) concentrations were measured. Reproductive history and health information, including Pap test results, were self-reported by participants.Of the women, 23% (223 of 956) reported an abnormal Pap test. In unadjusted analyses, self-reporting an abnormal Pap test was associated with younger age, current smoking (hazard ratio [HR] 1.61, 95% confidence interval [CI] 1.19-2.17), and longer duration of lifetime use of oral contraceptives (≥10 years; HR 1.92, 95% CI 1.21-3.06). When adjusting for PCB exposure, age at the interview, and smoking history, there was a slightly elevated risk of self-reporting an abnormal Pap test among the highly exposed women compared to women with nondetectable PBB concentrations (PBB≥13 μg/L, HR 1.23, 95% CI 0.74-2.06); however, the CI was imprecise. When breastfeeding duration after the initial PBB measurement was taken into account, there was a reduced risk of self-reporting an abnormal Pap test among the highly exposed women who breastfed for ≥12 months (HR 0.41, 95% CI 0.06-3.03; referent group: women with nondetectable PBB concentrations who did not breastfeed).It remains important to evaluate the potential reproductive health consequences of this class of chemicals as well as other potential predictors of abnormal Pap tests.

Background Polybrominated biphenyl (PBB), a brominated flame retardant, was accidently mixed into animal feed in Michigan (1973–1974) resulting in human exposure through consumption of contaminated meat, milk and eggs. Beginning in 1976 individuals who consumed contaminated products were enrolled in the Michigan Long-Term PBB Study. This cohort presents a unique opportunity to study the association between parental exposures to PBB and offspring sex ratio. Methods We identified offspring of female PBB cohort participants (born 1975–1988) and obtained electronic birth records for those born in the state of Michigan. We linked this information to parental serum PBB and PCB concentrations collected at enrollment into the cohort. We modeled the odds of a male birth with generalized estimating equations accounting for the non-independence of siblings born to the same parents. We explored potential confounders: parental age and education at offspring's birth, parental body mass index at cohort enrollment, birth order, gestational age and year of offspring's birth. Results The overall proportion of male offspring among 865 live births to cohort mothers was 0.542. This was higher than the national male proportion of 0.514 (binomial test: p = 0.10). When both parents were in the cohort (n = 300), we found increased odds of a male birth with combined parents' enrollment PBB exposure ≥ the median concentrations (3 μg/L for mothers; 6 μg/L for fathers) compared to combined parents' PBB exposure < the median concentrations (AOR = 1.43, 95% CI: 0.89–2.29), although this did not reach statistical significance. In addition, there was a suggestion of increased odds of a male birth for combined parents' enrollment PCB exposure ≥ the median concentrations (6 μg/L for mothers; 8 μg/L for fathers) compared to combined parents' enrollment PCB exposure < the median concentrations (AOR = 1.53, 95% CI: 0.93–2.52). Conclusion This study adds to the body of literature on secondary sex ratio and exposure to environmental contaminants. In this population, combined parental exposure to PBBs or PCBs increased the odds of a male birth. Further research is needed to corroborate these findings and shed light on the biological mechanisms by which these types of chemicals may influence the secondary sex ratio.

Studies have shown that the lipophilic nature of polybrominated biphenyl (PBB) causes it to preferentially accumulate in breast milk posing a potential hazard for suckling infants. The purpose of this study was to examine the inter-generational transfer of PBB from mother to child and whether this association was modified by maternal breast-feeding patterns. One hundred and forty-five mother-child pairs that were participants of the Michigan Long-Term PBB Study were included in this analysis. Mothers were exposed to PBB via contaminated food between 1973 and 1974 and children were exposed in utero and for some, through breast-feeding. Seventy-three percent of children had a non-detectable serum PBB concentration (limit of detection (LOD) = 1 microg L(-1)). Mothers' serum PBB concentration at enrollment ranged fromLOD to 933 microg L(-1). The following variables were associated with the child having a detectable serum PBB concentration: maternal serum PBBor =8 microg L(-1), breast-feedingor =5.5 months, maternal age at child's birthor =28 years, and being born during the PBB exposure period. Among mothers with a detectable serum PBB concentration, those who breast-fedor =5.5 months were 6 times more likely to have a child with a detectable serum PBB concentration, compared to a non-breast-fed child (95% C.I., 2.0-19.6).

Prior studies have reported an increased risk of diabetes related to polychlorinated biphenyl (PCB) exposure. No study has yet investigated whether polybrominated biphenyls (PBBs), which are similar in chemical structure, increase the incidence of diabetes.The Michigan PBB cohort was established in 1976 and surveyed again in 1991-1993 and in 2001. PBB and PCB serum levels were measured from blood collected at enrollment. To determine the incidence of adult-onset diabetes, we analyzed cohort members without diabetes at enrollment, ages 20 years and older, with known PBB and PCB levels, who participated in at least 1 follow-up survey (n = 1384). Using Poisson regression, we determined the incidence density ratio (IDR) of diabetes for different serum levels of PBB and PCB, controlling for age, body mass index, smoking, and alcohol consumption at enrollment.Analyzing 25 years of follow-up data, we did not find that higher PBB serum levels were a risk factor for the incidence of diabetes mellitus. However, in women, but not in men, higher PCB serum levels were associated with increased incidence of diabetes (IDR = 2.33; 95% confidence interval = 1.25-4.34 in the highest PCB group compared with the lowest). In both men and women, overweight and obesity increased the diabetes incidence.We found no association between PBB serum levels and diabetes incidence. In women, there was a positive linear association of diabetes incidence with PCB serum levels at enrollment. This finding is in agreement with 2 prior studies indicating a higher relative risk of diabetes in PCB-exposed women.

Contamination of fish in the Great Lakes generated three surveys assessing polychlorinated biphenyls (PCB) serum concentration in Michigan anglers: 1973 to 1974, 1979 to 1982, and 1989 to 1991. This cohort provided 1177 individuals with PCB determinations. In 2000, we conducted telephone interviews with parents on their children's birth characteristics. We estimated the sex odds ratio for parental PCB and dichlorodiphenyl dichloroethene concentrations using generalized estimation equations. We identified 208 offspring, within 101 families, born after 1963, with paternal measurements of both PCB and dichlorodiphenyl dichloroethene. When controlling for maternal exposure and parental dichlorodiphenyl dichloroethene, the sex odds ratio was increased if paternal PCB concentrations exceeded 8.1 micrograms/L (sex ratio, 2.29; 95% confidence interval, 1.11 to 4.74). Thus, paternal exposure was linked to a higher proportion of male offspring. These findings are opposite those reported for the Seveso study and are in accordance with those for dioxin exposure in the American veterans study.

BACKGROUND: US migrant and seasonal farmworkers may be exposed to potentially carcinogenic pesticides and other agents. Little epidemiologic research has been conducted on this population. METHODS: We examined the proportionate mortality of 26,148 subjects (14,631 white men (WM), 7,299 nonwhite men (NM), 1,081 white women (WW), and 3,137 nonwhite women (NW)) who were identified as farmworkers on death certificates from 24 US states during 1984-1993. RESULTS: Farmworkers had significantly elevated proportionate mortality from injuries, tuberculosis, mental disorders, cerebrovascular disease, respiratory diseases, ulcers, hypertension (NW), and cirrhosis (NW). There was significantly reduced mortality from infectious diseases (other than tuberculosis), endocrine disorders, nervous system diseases, pneumoconioses, arteriosclerotic heart disease (WM), and all cancers combined. Proportionate cancer mortality analyses found excess cancers of the buccal cavity, larynx, esophagus, stomach, skin (NW), and cervix, and deficits for cancers of the colon, breast, kidney, pancreas (NW), and lymphohematopoietic system. CONCLUSIONS: The excess deaths from injuries, respiratory disease, and stomach cancer, and the deficits of colon cancer and arteriosclerotic heart disease among farmworkers, are consistent with typical mortality patterns previously observed among farm owner/operators. The excess buccal, laryngeal, esophageal, and cervical cancers, and the deficits of breast cancer and lymphohematopoietic cancers have not generally been observed in studies of farm owner/operators.

Accidental contamination of the Michigan food chain with polybrominated biphenyls (PBBs) led to the exposure of more than 4,000 individuals in 1973. Because PBB exposure is suspected to disrupt endocrine function, we assessed pubertal development in females 5-24 years of age (N = 327) who were exposed to PBB in utero and, in many cases, through breastfeeding. We estimated in utero PBB exposure using maternal serum PBB measurements taken after exposure (1976-1979) and extrapolated to time of pregnancy using a model of PBB decay. We found that breastfed girls exposed to high levels of PBB in utero (or =7 parts per billion) had an earlier age at menarche (mean age = 11.6 years) than breastfed girls exposed to lower levels of PBB in utero (mean age = 12.2-12.6 years) or girls who were not breastfed (mean age = 12.7 years). This association persisted after adjustment for potential confounders (menarche ratio = 3.4, 95% confidence interval = 1.3-9.0). Perinatal PBB exposure was associated with earlier pubic hair stage in breastfed girls, but little association was found with breast development. The associations observed here lend support to the hypothesis that pubertal events may be affected by pre- and postnatal exposure to organohalogens.

A case-control study (8,740 cases; 83,338 controls) was done to evaluate the association between potential occupational exposure to silica and risk of tuberculosis (TB) mortality, using the National Occupational Mortality Surveillance database for 1983-1992. Potential silica exposure was based on the decedent's usual industry and occupation. Assignment of potential exposure to silica was based on the entire range of industries and occupations. Odds ratios (ORs) for mortality from respiratory TB associated with potential high and intermediate exposures to silica were 1.30 (95% CI 1.14-1.48) and 1.07 (95% CI 0.77-1.47), respectively, adjusting for silicosis, other pneumoconioses, age, gender, race, socioeconomic status, and potential exposure to active TB. The elevated OR was seen in all subgroups: male, female, white, and black. The average age at death among respiratory TB cases with potential silica exposure was significantly younger by four years than that among cases without potential silica exposure. The findings suggest that potential occupational exposure to silica alone, in the absence of silicosis, is associated with respiratory TB mortality, with a dose-response relationship.

To estimate the prevalence of carpal tunnel syndrome among US adults, data from the Occupational Health Supplement of the 1988 National Health Interview Survey were analyzed. Based on a sample of 44,233 households (response rate, 91.5%), an estimated 1.55% (2.65 million) of 170 million adults self-reported carpal tunnel syndrome in 1988. Females and Whites had a higher prevalence of self-reporting carpal tunnel syndrome than males and non-Whites, respectively. Among 127 million adults who worked during the 12 months before the survey, 0.53% (0.68 million) reported that their "prolonged" hand discomfort was called carpal tunnel syndrome by a health care provider.

Farmers in the United States suffer disproportionately from certain chronic diseases and impairments. This analysis estimated the prevalence of selected diseases among farmers and compared these rates with those for other US workers. Five years (1986-1990) of National Health Interview Survey data on white male workers were combined to provide a basis for estimating the prevalence of selected conditions and impairments among this subgroup. Crude prevalence rates were significantly elevated for farmers compared with other workers for cardiovascular diseases, arthritis, skin cancer, hearing loss, and amputations. These elevations persisted when farmers were compared with blue-collar workers. The crude prevalence of orthopedic impairments and chronic respiratory diseases was not elevated among farmers, but the age-adjusted prevalence ratios for cardiovascular diseases, arthritis, and amputations were significantly elevated for farmers as compared with other workers. The prevalence of hearing loss was significantly higher only for farmers older than 65 years. This method of pooling data holds promise for studying disease rates in other small segments of the US population. Language: en

Objective. —To determine trends in cigarette smoking prevalence among physicians, registered nurses, and licensed practical nurses since 1974. Design. —Analyses of data on smoking prevalence among persons 20 years of age and older using combined National Health Interview Survey data sets from 1974,1976, and 1977; 1978,1979, and 1980; 1983 and 1985; 1987 and 1988; and 1990 and 1991. Main Outcome Measures. —Prevalence of cigarette smoking and average annual change in smoking prevalence. Results. —Based on the data for 1990 and 1991, there were an estimated 18 000 physicians, 322 000 registered nurses, and 128 000 licensed practical nurses who smoked cigarettes in the United States. Compared with 1974, 1976, and 1977, by 1990 and 1991 cigarette smoking prevalence had declined from 18.8% to 3.3% among physicians (average annual decline of 1.15 percentage points); from 31.7% to 18.3% among registered nurses (average annual decline of 0.88 percentage point); and from 37.1% to 27.2% among licensed practical nurses (average annual decline of 0.62 percentage point). Conclusion. —Since 1974, cigarette smoking has declined most rapidly among physicians, at an intermediate rate among registered nurses, and at a lower rate among licensed practical nurses. Because of their important roles as exemplars and health educators, persons in these occupations should not smoke. ( JAMA . 1994;271:1273-1275)

Background Exposure to arsenic concentrations in drinking water in excess of 300 μg/L is associated with diseases of the circulatory and respiratory system, several types of cancer, and diabetes; however, little is known about the health consequences of exposure to low-to-moderate levels of arsenic (10–100 μg/L). Methods A standardized mortality ratio (SMR) analysis was conducted in a contiguous six county study area of southeastern Michigan to investigate the relationship between moderate arsenic levels and twenty-three selected disease outcomes. Disease outcomes included several types of cancer, diseases of the circulatory and respiratory system, diabetes mellitus, and kidney and liver diseases. Arsenic data were compiled from 9251 well water samples tested by the Michigan Department of Environmental Quality from 1983 through 2002. Michigan Resident Death Files data were amassed for 1979 through 1997 and sex-specific SMR analyses were conducted with indirect adjustment for age and race; 99% confidence intervals (CI) were reported. Results The six county study area had a population-weighted mean arsenic concentration of 11.00 μg/L and a population-weighted median of 7.58 μg/L. SMR analyses were conducted for the entire six county study area, for only Genesee County (the most populous and urban county), and for the five counties besides Genesee. Concordance of results across analyses is used to interpret the findings. Elevated mortality rates were observed for both males (M) and females (F) for all diseases of the circulatory system (M SMR, 1.11; CI, 1.09–1.13; F SMR, 1.15; CI, 1.13,-1.17), cerebrovascular diseases (M SMR, 1.19; CI, 1.14–1.25; F SMR, 1.19; CI, 1.15–1.23), diabetes mellitus (M SMR, 1.28; CI, 1.18–1.37; F SMR, 1.27; CI, 1.19–1.35), and kidney diseases (M SMR, 1.28; CI, 1.15–1.42; F SMR, 1.38; CI, 1.25–1.52). Conclusion This is some of the first evidence to suggest that exposure to low-to-moderate levels of arsenic in drinking water may be associated with several of the leading causes of mortality, although further epidemiologic studies are required to confirm the results suggested by this ecologic SMR analysis.

Background Alteration in menstrual cycle function is suggested among rhesus monkeys and humans exposed to polybrominated biphenyls (PBBs) and structurally similar polychlorinated biphenyls (PCBs). The feedback system for menstrual cycle function potentially allows multiple pathways for disruption directly through the hypothalamic-pituitary-ovarian axis and indirectly through alternative neuroendocrine axes. Methods The Michigan Female Health Study was conducted during 1997–1998 among women in a cohort exposed to PBBs in 1973. This study included 337 women with self-reported menstrual cycles of 20–35 days (age range: 24–56 years). Current PBB levels were estimated by exponential decay modeling of serum PBB levels collected from 1976–1987 during enrollment in the Michigan PBB cohort. Linear regression models for menstrual cycle length and the logarithm of bleed length used estimated current PBB exposure or enrollment PBB exposure categorized in tertiles, and for the upper decile. All models were adjusted for serum PCB levels, age, body mass index, history of at least 10% weight loss in the past year, physical activity, smoking, education, and household income. Results Higher levels of physical activity were associated with shorter bleed length, and increasing age was associated with shorter cycle length. Although no overall association was found between PBB exposure and menstrual cycle characteristics, a significant interaction between PBB exposures with past year weight loss was found. Longer bleed length and shorter cycle length were associated with higher PBB exposure among women with past year weight loss. Conclusion This study suggests that PBB exposure may impact ovarian function as indicated by menstrual cycle length and bleed length. However, these associations were found among the small number of women with recent weight loss suggesting either a chance finding or that mobilization of PBBs from lipid stores may be important. These results should be replicated with larger numbers of women exposed to similar lipophilic compounds.