Care for Adolescents With Polycystic Ovary Syndrome: Development and Prescribing Patterns of a Multidisciplinary Clinic

STUDY OBJECTIVE

Based on updated guidelines and expressed patient needs, we created a multidisciplinary clinic including endocrinology, gynecology/adolescent medicine, dermatology, psychology, and nutrition to provide comprehensive care to adolescent girls with polycystic ovary syndrome (PCOS). We describe the patient population presenting to this clinic, and prescribing patterns when a multidisciplinary approach is used.

DESIGN

Retrospective chart review.

SETTING

Tertiary care hospital.

PARTICIPANTS

Female patients, aged 11-24 years, presenting for initial assessment in a multidisciplinary PCOS clinic.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Medical history, physical examination findings, laboratory measurements and prescribed therapies.

RESULTS

A total of 92 patients seen from 2014 to 2018 are described (age 15.9 years, range 11-24 years, body mass index 35.6 kg/m2, range 19.9-53.5). Metabolic syndrome features were common: 26% had a prediabetes hemoglobin A1c (>5.6%), 83% had a high-density lipoprotein (HDL) <50 mg/dL, 40% had a systolic blood pressure >120 mm Hg, and 43% had an alanine aminotransferase level of >30 U/L. Dermatologic findings included acne 93%, hirsutism 38%, acanthosis nigricans 85%, hidradenitis suppurativa 16%, and androgenic alopecia 2%. Of the patients, 33% had a diagnosis of depression or anxiety, 16% of patients had a diagnosis of obstructive sleep apnea, and an additional 59% had symptoms warranting a sleep study The most commonly prescribed medications were topical acne preparations (62%), followed by estrogen-containing hormonal therapy (56%) and metformin (40%).

CONCLUSION

In adolescents with PCOS and obesity, metabolic, dermatologic, and psychologic co-morbidities are common. The use of a multidisciplinary clinic model including dermatology in addition to endocrinology, gynecology, psychology, and lifestyle experts provides care for most aspects of PCOS.

0924 Adolescent Perceptions of Insomnia Treatment

Introduction

Approximately 10% of adolescents meet diagnostic criteria for insomnia, which is associated with increased health problems, academic difficulties, and psychological morbidity. Empirical evidence supports cognitive-behavioral treatments for insomnia, yet research suggests adolescent insomnia is undertreated. Thus, the goal of this study was to evaluate adolescent perceptions about insomnia treatment seeking and strategies.

Methods

Adolescents ages 13-18 years with self-reported insomnia symptoms completed an online survey assessing treatment-seeking behaviors and management strategies. English-speaking participants were recruited using targeted Facebook advertising. Descriptive statistics were used to summarize results.

Results

Of the 3,014 survey respondents, participants were predominantly female (77%) and white non-Hispanic (71%), with a mean age of 16±1.3 years. Most (87%) met DSM-V diagnostic criteria for insomnia, but only 29% reported seeking professional help for insomnia. Of these, participants reported waiting an average of 1-2 years after symptom onset to seek treatment. Participants most often sought help from a mental health professional (18%) or primary care provider (13%), while &lt;2% saw a sleep specialist. Across adolescents, the most commonly endorsed strategies to manage insomnia symptoms were daytime caffeine consumption (48%), staying out of bed except when trying to sleep (38%), and daily exercise (28%). Nearly half of participants endorsed currently using medications to help with sleep, most commonly melatonin (18%) and antihistamine-based sleep aids (10%). Participants reported greatest preference to take medication (64%), meet individually with a sleep specialist (48%), or use a phone or tablet application (40%) to help with sleep. While 30% of participants felt that sleep researchers should prioritize increasing access to insomnia treatment, 20% encouraged developing new modes for treatment delivery (e.g., online).

Conclusion

Adolescents with insomnia reported using behavioral and pharmacological strategies to help with sleep, with very few receiving treatment from a sleep specialist. Further research is needed to increase accessibility and acceptability of interventions for adolescent insomnia.

Support

N/A

0921 Insomnia in Adolescents: Patient-Centered Outcomes and Perspectives

Introduction

An estimated 25-40% of adolescents endorse symptoms of insomnia. While research has demonstrated that insomnia is associated with impaired functioning, little is known regarding which insomnia symptoms or outcomes are most burdensome for adolescents. Patient-centered outcomes (PCO) are clinical and research questions and outcomes that are meaningful to patients. This study is the first to evaluate PCOs in adolescents with insomnia.

Methods

We conducted an online survey of adolescents in the USA, UK, Canada, Australia, and New Zealand who were 13 - 18 years old and reported experiencing one or more insomnia symptoms. Participants were recruited using targeted advertising on Facebook. Participants reported on insomnia symptom severity, frequency, and duration, help-seeking behavior, areas of insomnia-related impairment, and research priorities.

Results

Of the N=3034 respondents, 99.3% (n=3014) met inclusion criteria. Participants were predominantly female (77.0%) and white non-Hispanic (70.8%), with a mean age of 16.1 years (SD=1.3). Most (87.5%) met DSM-V diagnostic criteria for insomnia, yet only 29.3% reported seeking professional help. Over half (52.1%) reported a symptom duration of three or more years. Insomnia symptoms reported were sleep initiation difficulties (94.4%), sleep fragmentation (65.3%), premature awakening (54.5%), and difficulty sleeping independently (22.3%). The most burdensome areas of insomnia-related impairment were reported to be mood (72.2%), attentional focus (61.0%), pain (49.7%), worry (46.3%) and sleepiness (38.7%). Adolescents with insomnia most frequently endorsed the following research priorities: causes of insomnia (66.4%), early detection (66.1%), public education about sleep (49.1%) and non-pharmacological treatments (48.3%).

Conclusion

Adolescents with insomnia report significant insomnia-related distress and impairment, with symptoms often persisting for three or more years. However, adolescents with insomnia often do not seek professional help. Areas perceived as most problematic to adolescents living with insomnia (e.g., mood, focus, pain) should be considered as important outcomes for insomnia researchers.

Support

This publication was made possible with support from Grant Number UL1TR002529 (A Shekhar, PI) from the National Institutes of Health, National Center for Advancing Translational Sciences, Clinical and Translational Sciences Award and the Indiana University School of Medicine.

1029 Objectively-Measured Sleep Following a Time Restricted Eating Intervention in Adults With Obesity

Introduction

Time-restricted eating (TRE), limiting food intake to a consistent daily window, is emerging as a novel weight loss intervention but impact of TRE on sleep remains unclear. Prior studies reported mixed results but are limited by subjective sleep measurements and lack of a randomized control group. Thus, we examined changes in actigraphy-measured sleep following a 12-week TRE protocol.

Methods

Participants were 20 adults ages 18-65 years with BMI ≥24kg/m2. Participants were randomized to either TRE (8-hour eating window) or non-TRE (typical eating). At baseline and follow-up, all participants had anthropometric measurements, oral glucose tolerance test, logged eating occasions in a smartphone application, and wore an ActiGraph Link for two weeks. Independent samples t-tests compared groups on actigraphy-estimated sleep variables. Pearson correlations examined associations between sleep variables with health outcomes.

Results

The TRE (N=11) and non-TRE groups (N=9) were predominantly female and had a baseline eating window of approximately 15 hours. There were no differences in actigraphy-assessed sleep variables at baseline or follow-up between groups. Participants did not significantly change their sleep from baseline to follow-up. Median weekday sleep duration was 6.2 hours at follow-up for all participants, suggesting insufficient sleep compared to the recommended 7-9 hours of sleep. Participants who obtained greater than the median weekday sleep duration at follow-up had significantly lower BMI, better insulin sensitivity (HOMA and Matsuda Index), and greater percent improvement in insulin sensitivity.

Conclusion

Our data show that TRE does not significantly alter sleep behaviors in participants with obesity. However, longer sleep duration at follow-up was associated with lower BMI, better insulin sensitivity, and greater improvement in insulin sensitivity, indicating that sleep may be an important variable to consider in dietary interventions. Future research examining behavioral sleep strategies in combination with TRE is needed to evaluate whether improved sleep leads to better weight loss and glycemic outcomes for individuals with obesity.

Support

This work was support by the Healthy Foods Healthy Lives program (17SFR-2YR50LC to LC) and the National Institutes of Health (NIH National Center for Advancing Translational Sciences, UL1TR002494).

0886 Changes in Parent Knowledge and Self-Efficacy and Association With Adherence Following the Steps Towards Achieving Restful Sleep (STARS) Pediatric PAP Therapy Desensitization Program

Introduction

Obstructive sleep apnea (OSA) presents in 2-5 % of youth and has been consistently linked to sleepiness, cognitive deficits, behavior difficulties, and cardiovascular morbidity. PAP effectively treats OSA, however, nonadherence is the most common cause of PAP treatment failure in children. Few adherence interventions have been empirically studied for youth with OSA. The STARS (Steps Towards Achieving Restful Sleep) Clinic is a behavioral program to optimize child tolerance to PAP therapy through a parent class, and in vivo practice. The goal of the study was to examine parent knowledge and self-efficacy following participation in STARS, and associations with subsequent PAP adherence.

Methods

A retrospective chart review was conducted for patients in the STARS program. Items queried included patient demographics, diagnostic and treatment characteristics, pre- and post- STARS responses to a parent self-efficacy and knowledge questionnaire, and polysomnography and PAP adherence data. Paired-samples t-tests examined changes in parent self-efficacy and knowledge pre- to post STARS, and regression analyses examined associations between self-efficacy and knowledge with demographics, treatment-related characteristics, and PAP adherence.

Results

130 patients completed the STARS program from October 2016 to February 2019. Participants were 8.3 years old ±6.3, 63% male, 57% white, 33% Hispanic, with severe OSA (OAHI =22 ±33). Most participants (87%) had at least one medical comorbidity (e.g, Down Syndrome, 41%). Both parent knowledge and self-efficacy increased significantly from pre- to post- STARS. Approximately 60% of patients were adherent following STARS (defined as ≥4 h use and ≥70% of days used). Higher post- knowledge, but not efficacy score, was significantly associated with better PAP adherence.

Conclusion

Parent knowledge and self-efficacy for PAP improved following the STARS program, and greater knowledge was associated with better adherence. Future research evaluating the efficacy and effectiveness of the STARS program is needed but preliminary evidence suggests it may be a promising model for improving youth PAP adherence.

Support

None

0982 Content Analysis Of The Features And Claims Of Smartphone Applications For Children’s Sleep

Introduction

Empirically supported treatments for pediatric sleep problems exist but many families turn to other sources for help with their child’s sleep, such as smartphone applications (apps). Sleep apps are easy for families to access but little evidence exists regarding the validity of the services and information provided. The goal of this study was to examine the features and claims of sleep apps for children.

Methods

A search of the Apple iTunes store and Google Play Store was conducted using the terms “kids sleep” and “baby sleep”. 635 apps were initially identified. Apps were excluded if they were not specifically for children (n=163), not for sleep (n=152), or if they had &lt;100,000 downloads (n=246). Content analyses were used to assess the apps functions, claims, and evidence base.

Results

A total of 74 apps were examined of which only 4% offered sleep improvement strategies. The majority were sound and light apps (77%) and 19% were bedtime games/stories. The apps were highly rated (average 4.4 out of 5) and most were free (54%); the price of paid apps ranged from $0.99 to $119.99 (annual subscription). Only 2 apps were identified as containing empirical evidence, and all of the apps featuring games and stories to be used as part of the bedtime routine are in opposition to the recommendation to avoid the melatonin-suppressing effect of electronics/bright light before bedtime. Despite this, many apps boasted claims that they will help children “fall asleep instantly,” “cry less and sleep better,” or improve child development.

Conclusion

A large variety of sleep applications exist aimed for use with children. Many boast claims that cannot be supported by empirical evidence, and indeed may be in opposition to research support. Collaboration between sleep researchers and technology developers may be beneficial for the creation of evidence-supported apps to help with children’s sleep.

Support

N/A

Trends in Estimated Thyroid, Salivary Gland, Brain, and Eye Lens Doses From Intraoral Dental Radiography Over Seven Decades (1940 TO 2009)

The purpose of this study is to support retrospective dose estimation for epidemiological studies by providing estimates of historical absorbed organ doses to the brain, lens of the eye, salivary glands, and thyroid from intraoral dental radiographic examinations performed from 1940 to 2009. We simulated organ doses to an adult over 10 y time periods from 1940 to 2009, based on commonly used sets of x-ray machine settings collected from the literature. Simulations to estimate organ dose were performed using personal computer x-ray Monte Carlo software. Overall, organ doses were less than 1 mGy for a single intraoral radiograph for all decades. From 1940 to 2009, doses to the brain, eye lens, salivary glands, and thyroid decreased by 86, 96, 95, and 89%, respectively. Of these four organs, the salivary glands received the highest doses, with values decreasing from about 0.23 mGy in the 1940s to 0.025 mGy in the 2000s for a single intraoral radiograph. Based on simulations using collected historical data on x-ray technical parameters, improvements in technology and optimization of the technical settings used to perform intraoral dental radiography have resulted in a decrease in absorbed dose to the brain, eye lens, salivary glands, and thyroid over the period from 1940 to 2009.

The State Scientific Automated Medical Registry, Kazakhstan: an important resource for low-dose radiation health research

Direct quantitative assessment of health risks following exposure to ionizing radiation is based on findings from epidemiological studies. Populations affected by nuclear bomb testing are among those that allow such assessment. The population living around the former Soviet Union's Semipalatinsk nuclear test site is one of the largest human cohorts exposed to radiation from nuclear weapons tests. Following research that started in the 1960s, a registry that contains information on more than 300,000 individuals residing in the areas neighboring to the test site was established. Four nuclear weapons tests, conducted from 1949 to 1956, resulted in non-negligible radiation exposures to the public, corresponding up to approximately 300 mGy external dose. The registry contains relevant information about those who lived at the time of the testing as well as about their offspring, including biological material. An international group of scientists worked together within the research project SEMI-NUC funded by the European Union, and concluded that the registry provides a novel, mostly unexplored, and valuable resource for the assessment of the population risks associated with environmental radiation exposure. Suggestions for future studies and pathways on how to use the best dose assessment strategies have also been described in the project. Moreover, the registry could be used for research on other relevant public health topics.

Emergency Dose Estimation Using Optically Stimulated Luminescence from Human Tooth Enamel

Human teeth were studied for potential use as emergency Optically Stimulated Luminescence (OSL) dosimeters. By using multiple-teeth samples in combination with a custom-built sensitive OSL reader, (60)Co-equivalent doses below 0.64 Gy were measured immediately after exposure with the lowest value being 27 mGy for the most sensitive sample. The variability of OSL sensitivity, from individual to individual using multiple-teeth samples, was determined to be 53%. X-ray and beta exposure were found to produce OSL curves with the same shape that differed from those due to ultraviolet (UV) exposure; as a result, correlation was observed between OSL signals after X-ray and beta exposure and was absent if compared to OSL signals after UV exposure. Fading of the OSL signal was "typical" for most teeth with just a few of incisors showing atypical behavior. Typical fading dependences were described by a bi-exponential decay function with "fast" (decay time around of 12 min) and "slow" (decay time about 14 h) components. OSL detection limits, based on the techniques developed to-date, were found to be satisfactory from the point-of-view of medical triage requirements if conducted within 24 hours of the exposure.

UV effects in tooth enamel and their possible application in EPR dosimetry with front teeth

The effects of ultraviolet (UV) radiation on ionizing radiation biodosimetry were studied in human tooth enamel samples using the technique of electron paramagnetic resonance (EPR) in X-band. For samples in the form of grains, UV-specific EPR spectra were spectrally distinct from those produced by exposure to gamma radiation. From larger enamel samples, the UV penetration depth was determined to be in the 60-120 mum range. The difference in EPR spectra from UV exposure and from exposure to gamma radiation samples was found to be a useful marker of UV equivalent dose (defined as the apparent contribution to the gamma dose in mGy that results from UV radiation absorption) in tooth enamel. This concept was preliminarily tested on front teeth from inhabitants of the region of the Semipalatinsk Nuclear Test Site (Kazakhstan) who might have received some exposure to gamma radiation from the nuclear tests conducted there as well as from normal UV radiation in sunlight. The technique developed here to quantify and subtract the UV contribution to the measured tooth is currently limited to cumulative dose measurements with a component of UV equivalent dose equal to or greater than 300 mGy.

Optically stimulated luminescence (OSL) of tooth enamel and its potential use in post-radiation exposure triage

Optically stimulated luminescence (OSL) properties of dental enamel are discussed with a view to the development of an in vivo dose assessment technique for medical triage following a radiological/nuclear accident or terrorist event. In the OSL technique, past radiation exposure is assessed by stimulating the sample with light of one wavelength and monitoring the luminescence at another wavelength, under the assumption that the luminescence originates from the recombination of radiation-induced charges trapped at metastable defects in the enamel and that the intensity of the luminescence signal is in proportion to the absorbed radiation dose. Several primary findings emerged from this research: (a) sensitivities varied considerably between different teeth and also between fragments of the same tooth, (b) OSL signals were found to decay rapidly during the first 12 h after irradiation and more slowly afterward, (c) the fading rate of the luminescence signal varied between fragments, and (d) blue light stimulation yields greater sensitivity than infra-red stimulation, while the OSL signal obtained with a high-intensity pulsed green-light laser was found not to be correlated with the radiation dose. Significant challenges remain to developing a practical in vivo technique, including the development of calibration procedures and lowering minimum detectable doses.

Validation of 131I ecological transfer models and thyroid dose assessments using Chernobyl fallout data from the Plavsk district, Russia

Within the project "Environmental Modelling for Radiation Safety" (EMRAS) organized by the IAEA in 2003 experimental data of (131)I measurements following the Chernobyl accident in the Plavsk district of Tula region, Russia were used to validate the calculations of some radioecological transfer models. Nine models participated in the inter-comparison. Levels of (137)Cs soil contamination in all the settlements and (131)I/(137)Cs isotopic ratios in the depositions in some locations were used as the main input information. 370 measurements of (131)I content in thyroid of townspeople and villagers, and 90 measurements of (131)I concentration in milk were used for validation of the model predictions. A remarkable improvement in models performance comparing with previous inter-comparison exercise was demonstrated. Predictions of the various models were within a factor of three relative to the observations, discrepancies between the estimates of average doses to thyroid produced by most participant not exceeded a factor of ten.

Radiation dose to the brain and subsequent risk of developing brain tumors in pediatric patients undergoing interventional neuroradiology procedures

Radiation dose to the brain and subsequent lifetime risk of diagnosis of radiation-related brain tumors were estimated for pediatric patients undergoing intracranial embolization. Average dose to the whole brain was calculated using dosimetric data from the Radiation Doses in Interventional Radiology Study for 49 pediatric patients who underwent neuroradiological procedures, and lifetime risk of developing radiation-related brain tumors was estimated using published algorithms based on A-bomb survivor data. The distribution of absorbed dose within the brain can vary significantly depending on field size and movement during procedures. Depending on the exposure conditions and age of the patient, organ-averaged brain dose was estimated to vary from 6 to 1600 mGy. The lifetime risk of brain tumor diagnosis was estimated to be increased over the normal background rates (57 cases per 10,000) by 3 to 40% depending on the dose received, age at exposure, and gender. While significant uncertainties are associated with these estimates, we have quantified the range of possible dose and propagated the uncertainty to derive a credible range of estimated lifetime risk for each subject. Collimation and limiting fluoroscopy time and dose rate are the most effective means to minimize dose and risk of future induction of radiation-related tumors.

Childhood cancer in the offspring born in 1921-1984 to US radiologic technologists

We examined the risk of childhood cancer (<20 years) among 105 950 offspring born in 1921-1984 to US radiologic technologist (USRT) cohort members. Parental occupational in utero and preconception ionising radiation (IR) testis or ovary doses were estimated from work history data, badge dose data, and literature doses (the latter doses before 1960). Female and male RTs reported a total of 111 and 34 haematopoietic malignancies and 115 and 34 solid tumours, respectively, in their offspring. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression. Leukaemia (n=63) and solid tumours (n=115) in offspring were not associated with maternal in utero or preconception radiation exposure. Risks for lymphoma (n=44) in those with estimated doses of <0.2, 0.2-1.0, and >1.0 mGy vs no exposure were non-significantly elevated with HRs of 2.3, 1.8, and 2.7. Paternal preconception exposure to estimated cumulative doses above the 95th percentile (82 mGy, n=6 cases) was associated with a non-significant risk of childhood cancer of 1.8 (95% CI 0.7-4.6). In conclusion, we found no convincing evidence of an increased risk of childhood cancer in the offspring of RTs in association with parental occupational radiation exposure.

Ultrasound-detected thyroid nodule prevalence and radiation dose from fallout

Settlements near the Semipalatinsk Test Site (SNTS) in northeastern Kazakhstan were exposed to radioactive fallout during 1949-1962. Thyroid disease prevalence among 2994 residents of eight villages was ascertained by ultrasound screening. Malignancy was determined by cytopathology. Individual thyroid doses from external and internal radiation sources were reconstructed from fallout deposition patterns, residential histories and diet, including childhood milk consumption. Point estimates of individual external and internal dose averaged 0.04 Gy (range 0-0.65) and 0.31 Gy (0-9.6), respectively, with a Pearson correlation coefficient of 0.46. Ultrasound-detected thyroid nodule prevalence was 18% and 39% among males and females, respectively. It was significantly and independently associated with both external and internal dose, the main study finding. The estimated relative biological effectiveness of internal compared to external radiation dose was 0.33, with 95% confidence bounds of 0.09-3.11. Prevalence of papillary cancer was 0.9% and was not significantly associated with radiation dose. In terms of excess relative risk per unit dose, our dose-response findings for nodule prevalence are comparable to those from populations exposed to medical X rays and to acute radiation from the Hiroshima and Nagasaki atomic bombings.

Optically Stimulated Luminescence (OSL) of dental enamel for retrospective assessment of radiation exposure

This paper briefly reviews the optically stimulated luminescence (OSL) properties of dental enamel and discusses the potential and challenges of OSL for filling the technology gap in biodosimetry required for medical triage following a radiological/nuclear accident or terrorist event. The OSL technique uses light to stimulate a radiation-induced luminescence signal from materials previously exposed to ionizing radiation. This luminescence originates from radiation-induced defects in insulating crystals and is proportional to the absorbed dose of ionizing radiation. In our research conducted to date, we focused on fundamental investigations of the OSL properties of dental enamel using extracted teeth and tabletop OSL readers. The objective was to obtain information to support the development of the necessary instrumentation for retrospective dosimetry using dental enamel in laboratory, or for in situ and non-invasive accident dosimetry using dental enamel in emergency triage. An OSL signal from human dental enamel was detected using blue, green, or IR stimulation. Blue/green stimulation associated with UV emission detection seems to be the most appropriate combination in the sense that there is no signal from un-irradiated samples and the shape of the OSL decay is clear. Improvements in the minimum detection level were achieved by incorporating an ellipsoidal mirror in the OSL system to maximize light collection. Other possibilities to improve the sensitivity and research steps necessary to establish the feasibility of the technique for retrospective assessment of radiation exposure are also discussed.

Effects of entanglement concentration on Tg and local segmental motions

The process of spin-coating to fabricate thin polymer films with high molecular weight can produce samples with entanglement concentrations that are far below the equilibrium value. It is not clear whether or not such low entanglement concentrations are responsible for the depression of the glass temperature in thin polymer films. In this work, we measure the calorimetric glass temperature and viscoelastic response of polystyrenes with molecular weights ranging from 3x10(3) to 43.7x10(6) g/mol, for both bulk material and for samples freeze-dried from dilute solution. We conclude that the reduction of the glass temperature observed in thin polymer films cannot be due to the reduced entanglement concentration in the samples.

Enthalpy recovery of a glass-forming liquid constrained in a nanoporous matrix: negative pressure effects

The T(g) of organic liquids confined to nanoporous matrices and that of thin polymer films can decrease dramatically from the bulk value. One possible explanation for this phenomenon is the development of hydrostatic tension during vitrification under confinement that results in a concomitant increase in the free volume. Here we present experimental evidence and modeling results for ortho-terphenyl (o-TP) confined in pores as small as 11.6 nm that indicate that, although there is an important hydrostatic tension in the liquid in the pores, it does not develop until near the reduced T(g) of the constrained material --well below the bulk T(g). Enthalpy recovery for the o-TP in the nanopores exhibits accelerated physical aging relative to the bulk, as well as a leveling off of the fictive temperature at equilibrium values greater than the aging temperature. An adaptation of the structural recovery model that incorporates vitrification under isochoric conditions is able to provide a quantitative explanation for the apparently anomalous aging observed in nanopore confined liquids and in thin polymeric films. The results strongly support the existence of an intrinsic size effect as the cause of the reduced T(g).

Uptake of 40K and 137Cs in native plants of the Marshall Islands

Uptake of 137Cs and 40K was studied in seven native plant species of the Marshall Islands. Plant and soil samples were obtained across a broad range of soil 137Cs concentrations (0.08-3900 Bq/kg) and a narrower range of 40K soil concentrations (2.3-55 Bq/kg), but with no systematic variation of 40K relative to 137Cs. Potassium-40 concentrations in plants varied little within the range of 40K soil concentrations observed. Unlike the case for 40K, 137Cs concentrations increased in plants with increasing 137Cs soil concentrations though not precisely in a proportionate manner. The best-fit relationship between soil and plant concentrations was P = aSb where a and b are regression coefficients and P and S are plant and soil concentrations, respectively. The exponent b for 40K was zero, implying plant concentrations were a single value, while b for 137Cs varied between 0.51 and 0.82, depending on the species. For both 40K and 137Cs, we observed a decreasing concentration ratio (where concentration ratio=plant concentration/soil concentration) with increasing soil concentrations. For the CR values, the best-fit relationship was of the form CR = aSb/S = aSb(-1). For the 40K CR functions, the exponent b - 1 was close to - 1 for all species. For the 137Cs CR functions, the exponent b - 1 varied from -0.19 to -0.48. The findings presented here, aswell as those by other investigators, collectively argue against the usefulness of simplistic ratio models to accurately predict uptake of either 40K or 137Cs in plants over wide ranges of soil concentration.

Cognitive impairment in individuals currently using methamphetamine

Although there are increasing reports of methamphetamine use, studies examining the cognitive consequences of methamphetamine have not been performed on a population currently using the drug. To characterize this population, 65 people currently using MA regularly and 65 non-users were given a battery of cognitive tests. The battery included recall, recognition, Digit Symbol, Trail Making A & B, Stroop, Wisconsin Card Sort, backward digit span, and the FAS test of verbal fluency. The methamphetamine users were significantly more impaired on recall tasks, digit symbol, Stroop color words, and Trail Making B, but scores fell within the normal ranges on the other measures.

Altered expression of estrogen receptor coregulators during human breast tumorigenesis

The hypothesis that altered expression of specific coactivators/repressors of the estrogen receptor occurs during human breast tumorigenesis in vivo is examined in this study. Using in situ hybridization and reverse transcription-PCR assays, the expression of two coactivators (SRA and AIB1) and one repressor (REA) of the estrogen receptor was compared between matched breast tumors and adjacent normal human breast tissue. The levels of SRA and AIB1 mRNA were increased in tumors compared with normal tissues (n = 19; Wilcoxon matched pairs test; P < 0.01). In contrast, the expression of REA mRNA was not different between tumors and normal tissues (n = 19; Wilcoxon; P = 0.110). The ratios of AIB1:REA and SRA:REA were higher (Wilcoxon; P < 0.05) in tumors compared with normal tissues. Furthermore, SRA:AIB1 was higher (Wilcoxon; P = 0.0058) in tumors compared with normal tissues. Although our study is small, these data are consistent with the above hypothesis and suggest that such alterations may have a role in the altered estrogen action occurring during breast tumorigenesis.

Expression of a repressor of estrogen receptor activity in human breast tumors: relationship to some known prognostic markers

The expression of a specific repressor of estrogen receptor activity (REA) was investigated by a semiquantitative reverse transcription-PCR assay in 40 human breast tumor biopsy samples with respect to steroid hormone receptor status and other known prognostic variables. The data showed that REA expression was positively correlated with estrogen receptor (ER) levels as defined by ligand-binding assays (Spearman r = 03231; P = 0.042) and that the median level of REA mRNA was significantly (Mann-Whitney two-tailed test, P = 0.0424) higher in ER+ tumors (median = 94.5; n = 30) compared with ER- tumors (median = 645; n = 10), with no significant differences (P = 0.4988) associated with progesterone receptor status alone. In addition, REA expression was inversely correlated with tumor grade (Spearman r = -0.4375; P = 0.0054). When the tumors were divided into two groups based on grade, REA expression was significantly (Mann-Whitney two-tailed test, P = 0.0024) higher in low-grade (median = 97; n = 16) compared with high-grade (median = 76; n = 23) tumors. These results provide preliminary data suggesting that the expression of REA varies among breast tumors and is correlated with known treatment response markers and inversely correlated with a marker of breast cancer progression. REA together with ER status may be an improved marker of endocrine therapy responsiveness in human breast cancer.

A comparison of injecting and noninjecting methamphetamine users

The injection of illicit drugs exposes the user to a variety of risks that are not associated with other routes of administration. Information regarding differences between injecting and noninjecting methamphetamine (MA) users is provided. The population studied included MA dependent men and women (n = 427) from the Matrix Institute on Addictions in San Bernardino County, California. The sample was divided into two groups according to their injecting status; 55 individuals (13%) reported injecting, and 372 (87%) reported no history of injecting MA. Differences were found in specific use patterns and in medical, criminal, and psychological histories between the two groups.

Thyroid nodules, thyroid function and dietary iodine in the Marshall islands

BACKGROUND

Thyroid nodules have been found to be common in the population of the Marshall Islands. This has been attributed to potential exposure of radioiodines from the nuclear weapons tests on Bikini and Eniwetok between 1946 and 1958.

METHODS

In order to get a full picture of thyroid pathology in the Marshallese population potentially exposed to radioactive fallout we performed a large thyroid screening programme using palpation, high resolution ultrasound and fine needle biopsies of palpable nodules. In addition, various parameters of thyroid function (free T3, free T4, thyroid stimulating hormone [TSH]) and anti-thyroid antibodies were examined in large proportions of the total population at risk. Since dietary iodine deficiency is an established risk factor for thyroid nodules, iodine concentration in urine samples of 362 adults and 119 children was measured as well as the iodine content of selected staple food products.

RESULTS

The expected high prevalence of thyroid nodules was confirmed. There was no indication of an increased rate of impaired thyroid function in the Marshallese population. A moderate degree of iodine deficiency was found which may be responsible for some of the increased prevalence of thyroid nodules in the Marshallese population.

CONCLUSIONS

Studies on the relationship between exposure to radioiodines and thyroid nodules need to take dietary iodine deficiency into account in the interpretation of findings.

A progress report of the Marshall Islands nationwide thyroid study: an international cooperative scientific study

The objective of this report is to present a summary of progress of the Marshall Islands Nationwide Thyroid Study. As well known, the US atomic weapons testing program in the Pacific was conducted primarily between 1946 and 1958 in the Marshall Islands. The nuclear tests resulted in radioactive contamination of a number of atolls and resulted in exposure of Marshallese to undefined levels before our study. Little information has been paid to health consequences among residents of the nearly twenty inhibited atolls except for some information about nodular thyroid disease which was reported on by an US group. In a cooperative agreement with the Government of the Marshall Islands, between 1993 and 1997 we studied the prevalence of both thyroid nodules and thyroid cancer among 4766 Marshallese potentially exposed to radioiodines from bomb test fallout. That group represents more than 65% of the population at risk. We diagnosed 45 thyroid cancers and 1398 benign thyroid nodules. In addition, 23 study participants had been operated on prior to our study for thyroid cancer. Presently, we are developing a database of information to estimate radiation doses and planning a statistical analysis to determine if a dose-response relationship exists. These data will be important for the health promotion of exposed people all over the world including Hiroshima, Nagasaki, Semipalatinsk, Chernobyl and other locations. A timely completion is important for purpose of assisting Marshallese as well as to add the global understanding of radiation induced thyroid cancer.

Special care units for Alzheimer's patients: their role in the nursing home market

The Special Care Unit (SCU) is a new, rapidly proliferating mode of caring for people with Alzheimer's disease (AD). Approximately 10% of nursing homes within the U.S. have SCUs with the number expected to grow substantially in coming years. SCUs are largely unregulated and not uncontroversial. This article discusses their emergence over time, their origins, growth, and the call for standardization. Subsequent sections review the range of potential benefits and costs associated with SCUs, optimally defined as well as research evidence available on this mode of care. Recent cost-setting and reform pressures in the nursing home industry are discussed in the final sections along with the likely future of AD SCUs in this environment.

Soil ingestion by humans: a review of history, data, and etiology with application to risk assessment of radioactively contaminated soil

Ingestion of soil by humans has been a documented phenomenon for centuries and still takes place today according to various literature. The literature reviewed here shows that there are two distinct soil ingestion phenomenon: inadvertent and purposeful (geophagia). Certain lifestyles, occupations, and living conditions will likely put different individuals or different groups at risk to these separate, but sometimes related, phenomenon. In particular, reports of geophagia are relatively common for the life stages of adolescence and periods of growth, and during pregnancy and lactation. Geophagia also appears to be relatively common among indigenous peoples on all continents, sometimes taking place to extreme degrees. Because of their high dependence on the land, indigenous peoples are also at highest risk for inadvertent ingestion. Inadvertent intake is more a function of either primitive living conditions or professions that may bring workers into close and continual contact with the soil. It is the purpose of this report to review and summarize literature related to ingestion of soil by humans with emphasis on the relevance of soil ingestion to radiological dose assessment, the etiology of geophagia and its relationship to risk assessment, qualitative observations and quantitative studies of direct soil ingestion by humans with interpretations useful for different lifestyle scenarios, the status of a number of current radiological assessment models in accounting for soil ingestion, and some unresolved issues in modeling the ingestion of soil.

Brain structure and function and the outcomes of treatment for depression

BACKGROUND

Depressed patients have a variety of brain structural alterations, the most common being atrophy and deep white-matter lesions. Alterations in brain function also are common, particularly regional decreases in cerebral metabolism and perfusion.

METHOD

We review here the evidence that alterations in brain structure and function may explain some of the heterogeneity in outcomes of depression. We also report initial results suggesting that measurement of brain structure and function may help to predict outcomes of treatment for depression. Brain structure was examined using three-dimensional reconstruction and volumetric analysis of magnetic resonance imaging (MRI) scans. Brain function was examined using quantitative electroencephalography (QEEG), performed at baseline and serially during the course of treatment. QEEG measures included coherence (a measure of synchronized activity between brain regions) and cordance (a measure strongly associated with regional cerebral perfusion).

RESULTS

Depressed patients have been reported to have larger volumes of white-matter lesions than controls. We have found that some types of white-matter lesions are associated with lower coherence and that subjects with low coherence had significantly poorer outcomes of treatment for depression at 2-year follow-up. Depressed subjects had low cordance at baseline, which decreased further during the course of effective treatment. Subjects who did not improve had little or no change in cordance. Changes in cordance were detected prior to the onset of clinical response, with decreases seen as early as 48 hours after the initiation of treatment in subjects who showed eventual response.

CONCLUSION

These preliminary results suggest that functional imaging using QEEG may be useful for assessing, and possibly predicting, outcomes of treatment for depression.

Some reflections on the role of the Scientific Advisory Panel to the Marshall Islands nationwide radiological study

As a consequence of the U.S. Atomic Weapons Testing Program in the Trust Territory of the Pacific, now the Republic of the Marshall Islands, numerous scientists have advised the Marshallese on matters of radiation and radioactive contamination. Some of the previous advice has appeared to vary or conflict resulting in consequent uncertainty for the people. In a new initiative in 1989, the RMI Government engaged a five member multi-disciplinary Scientific Advisory Panel to oversee the assessment of, and to advise on, the radiological status of the entire nation. The formation of the Panel was accompanied by the establishment of a Resident Scientist position, and ultimately a small scientific team and laboratory on Majuro. The nationwide radiological study was conducted using ground survey methods over the period 1990-1994. Tasks undertaken by the Panel included formulating reasonable objectives for the study and attempting to establish effective communication and understanding of issues with political leaders and RMI Government agencies and people, as well as advising on and monitoring the scientific integrity of the study itself. The attempt was also made to initiate investigations to address matters of concern that emerged. The problem was faced of providing not only technical guidance on radioactivity and radiation measurements, but also explaining the significance of measured values and concepts, such as risk and probability of health effects to a diverse but nontechnical audience, generally across cultural and language barriers. The experience of the Panel in providing advice and guidance to the Republic of the Marshall Islands, while unique in many ways, parallels the difficulties experienced elsewhere in communicating information about risks from radiation exposure.

A brief history of people and events related to atomic weapons testing in the Marshall Islands

The events related to nuclear testing in the Marshall Islands began at the end of WWII when the U.S. began an initiative to determine the effect of nuclear weapons on naval vessels and on the performance of military personnel. The first tests took place in 1946 even though the area known as Micronesia was not entrusted to the U.S. by the United Nations until 1947. Beginning with the first relocation of the Bikini people to Rongerik Atoll in 1946, the saga of the Marshall Islands involvement in the atomic age began. Although the testing program was limited to the years 1946 through 1958, many of the consequences and events related to the testing program continued over the decades since. That story is still ongoing with programs currently underway to attempt to resettle previously displaced communities, remediate contaminated islands, and to settle claims of damages to individuals and communities. The history of the years subsequent to 1958 are a mixed chronicle of a few original scientific investigations aimed at understanding the coral atoll environment, continued surveillance of the acutely exposed Marshallese, some efforts at cleanup and remediation, numerous monitoring programs and many studies repeated either for credibility purposes, to satisfy international demands or because the changing state of knowledge of radiation protection has necessitated us to rethink earlier beliefs and conclusions about late health effects and social consequences. The objective of this paper is to briefly note many of the historical and political events, scientific studies, persons and publications from 1946 to the present that relate to atomic weapons testing in the Marshall Islands.

An investigation into the prevalence of thyroid disease on Kwajalein Atoll, Marshall Islands

The prevalence of thyroid nodules and thyroid cancer was studied in the indigenous population residing on Ebeye Island, Kwajalein Atoll, in the Republic of the Marshall Islands. This island, centrally located in the nation, is home to about 25% of the nation's population, many who have migrated there from other atolls. The objective of the study was to obtain thyroid disease rate statistics on as much of the population as possible that was alive during the years of nuclear testing and to test the hypothesis that described a linearly decreasing prevalence of palpable nodules with increasing distance from the Bikini test site. 1,322 Marshallese born before 1965 were given a thyroid examination using neck palpation, fine needle aspiration biopsy, and high resolution ultrasound imaging. Approximately 40% of the total population living on this island who are at risk from exposure to radioactive fallout during the years 1946-1958 were screened. Of that group, 815 were alive at the time of the BRAVO test on 1 March 1954. Two hundred sixty-six people with thyroid nodules were found (32.6%): 132 were palpable nodules (16.2%), and 134 were nodules that could be diagnosed with ultrasound only (15.7%). Prevalence of palpable nodules was particularly high in men and women older than 60 y, in men who were 6 to 15 y of age at the time of the BRAVO test, and in women 1 to 10 y of age at the time of the BRAVO test. In 22 people, the clinical diagnosis was most likely cancer though histopathological evidence was only available from 11 operated cases. Of the 11 operated cases, 10 were cancer. Cancer prevalence was particularly high in those women born between 1944 and 1953 (7/220 = 3.2%), i.e., who were children during the early years of nuclear testing. The Ebeye data showed a marginally significant correlation between palpable nodule prevalence among women and distance to Bikini (r = -0.44, p = 0.06). This report summarizes the clinical findings of the thyroid examinations, the age distributions for nodular disease and cancer, and examines the relationship between prevalence of nodules and present day levels of 137Cs in the environment of each atoll.

A comparison of independently conducted dose assessments to determine compliance and resettlement options for the people of Rongelap Atoll

Rongelap Island was the home of Marshallese people numbering less than 120 in 1954; 67 were on the island and severely exposed to radioactive fallout from an atomic weapons test in March of that year. Those resident on Rongelap were evacuated 50 h after the test, returned 3 y later, then voluntarily left their home island in 1985 due to their ongoing fear of radiation exposure from residual radioactive contamination. Following international negotiations in 1991, a Memorandum of Understanding (MOU) was signed in early 1992 between the Republic of the Marshall Islands Government, the Rongelap Atoll Local Government, the U.S. Department of Energy, and the U.S. Department of the Interior. In this MOU it was agreed that the Republic of the Marshall Islands, with the aid of the U.S. Department of Energy, would carry out independent dose assessments for the purpose of assisting and advising the Rongelap community on radiological issues related to a safe resettlement of Rongelap. The MOU enacted two action levels which were agreed to be used to establish whether mitigation should be considered as a condition for resettlement of Rongelap Island: (1) no individual should receive an annual dose in the future of 1 mSv or more, above that from natural background radiation, assuming that his/her diet consists of only locally produced foods, and (2) the total surface soil concentration of plutonium and other transuranic elements must be less than 629 Bq kg(-1) (averaged over the top 5 cm). Environmental radiological data and dietary information were collected over two years (1992-1993) for the purpose of predicting future potential doses to Rongelapese who might resettle. In 1994, four independent assessments were reported, including one from each of the following entities: Marshall Islands Nationwide Radiological Study; Lawrence Livermore National Laboratory; an independent advisor from the United Kingdom (MCT); and a committee of the National Research Council. All four assessments concluded that possibly more than 25% of the adult population could exceed the 1 mSv y(-1) dose level based on strict utilization of a local food diet. The purpose of this report is to summarize the methodology, assumptions, and findings from each of four assessments; to summarize the recommendations related to mitigation and resettlement options; to discuss unique programmatic aspects of the study; and to consider the implications of the findings to the future of the Rongelap people.

Findings of the first comprehensive radiological monitoring program of the Republic of the Marshall Islands

The Marshall Islands was the primary site of the United States atomic weapons testing program in the Pacific. From 1946 through 1958, 66 atomic weapons were detonated in the island country. For several decades, monitoring was conducted by the U.S. Department of Energy (or its predecessor agencies) on the test site atolls and neighboring atolls. However, 70% of the land area of the over 1,200 islands in the Marshall Islands was never systematically monitored prior to 1990. For the 5-y period from 1990 through 1994, the Government of the Republic of the Marshall Islands undertook an independent program to assess the radiological conditions throughout its 29 atolls. The scientific work was performed under the auspices of the Section 177 Agreement of the Compact of Free Association, U.S. public law 99-239, signed in 1986 by President Ronald Reagan. Although the total land area of the nations is a scant 180 km2, the islands are distributed over 6 x 10(5) km2 of ocean. Consequently, logistics and instrumentation were main considerations, in addition to cultural and language issues. The core of the monitoring program was in-situ gamma spectrometry measurements made on more than 400 islands. Native foods including coconuts and other tropical fruits were sampled as well as more than 200 soil profiles and more than 800 surface soil samples. The fruits, soil profiles and surface soil samples have been analyzed for all gamma emitters with an emphasis on determining concentrations of 137Cs; the surface soil samples were also analyzed for 239+240Pu. All measurements were conducted in a radiological laboratory built in the capital city of the Marshall Islands specifically for the purposes of this study. The program was extensively assisted in the field and in the laboratory by Marshallese workers. The interpretation of environmental radiation data in the Marshall Islands required thoughtful analysis because the atolls lie along a latitude and precipitation gradient that effected the deposition of local and global fallout. The objective of this paper is to report findings for all atolls of the Marshall Islands on the 137Cs areal inventory (Bq m(-2)) and the external effective dose-rate (mSv y(-1)), the projected internal effective dose-rate (mSv y(-1)) from an assumed diet model, and surface soil concentrations of 239,240Pu (Bq kg(-1)) for selected northern atolls. Interpretation is also provided on the degree of contamination above global fallout levels. This report provides the first comprehensive summary of the radiological conditions throughout the Marshall Islands.

A compilation of nuclear weapons test detonation data for U.S. Pacific ocean tests

Prior to December 1993, the explosive yields of 44 of 66 nuclear tests conducted by the United States in the Marshall Islands were still classified. Following a request from the Government of the Republic of the Marshall Islands to the U.S. Department of Energy to release this information, the Secretary of Energy declassified and released to the public the explosive yields of the Pacific nuclear tests. This paper presents a synopsis of information on nuclear test detonations in the Marshall Islands and other locations in the mid-Pacific including dates, explosive yields, locations, weapon placement, and summary statistics.

Dose assessment activities in the Republic of the Marshall Islands

Dose assessments, both retrospective and prospective, comprise one important function of a radiological study commissioned by the Republic of the Marshall Islands (RMI) government in late 1989. Estimating past or future exposure requires the synthesis of information from historical data, results from a recently completed field monitoring program, laboratory measurements, and some experimental studies. Most of the activities in the RMI to date have emphasized a pragmatic rather than theoretical approach. In particular, most of the recent effort has been expended on conducting an independent radiological monitoring program to determine the degree of deposition and the geographical extent of weapons test fallout over the nation. Contamination levels on 70% of the land mass of the Marshall Islands were unknown prior to 1994. The environmental radioactivity data play an integral role in both retrospective and prospective assessments. One recent use of dose assessment has been to interpret environmental measurements of radioactivity into annual doses that might be expected at every atoll. A second use for dose assessment has been to determine compliance with a dose action level for the rehabilitation of Rongelap Island. Careful examination of exposure pathways relevant to the island lifestyle has been necessary to accommodate these purposes. Examples of specific issues studied include defining traditional island diets as well as current day variations, sources of drinking water, uses of tropical plants including those consumed for food and for medicinal purposes, the nature and microvariability of plutonium particles in the soil and unusual pathways of exposure, e.g., that which might be associated with cooking and washing outdoors and inadvertent soil ingestion. A study on the prevalence of thyroid disease is also being conducted and the geographic pattern of disease may be useful as a bioindicator of the geographic pattern of exposure to radioiodine. Finally, an examination is underway of gummed film, fixed-instrument, and aerial survey data accumulated during the 1950's by the Health and Safety Laboratory of the U.S. AEC. This article gives an overview of these many different activities and a summary of recent dose assessments.

The Utah Leukemia Case-Control Study: dosimetry methodology and results

This paper discusses the dosimetry methodology used to estimate bone marrow dose and the results of dosimetry calculations for 6,507 subjects in an epidemiologic case-control study of leukemia among Utah residents. The estimated doses were used to determine if a higher incidence of leukemia among residents of Utah could have been attributed to exposure to radioactive fallout from above-ground nuclear weapons tests conducted at the Nevada Test Site. The objective of the dosimetry methodology was to estimate absorbed dose to active marrow specific to each case and each control subject. Data on the residence of each subject were available from records of the Church of Jesus Christ of Latter-day Saints. Deposition of fallout was determined from databases developed using historical measurements and exposure for each subject from each test was estimated using those data. Exposure was converted to dose by applying an age-dependent dose conversion factor and a factor for shielding. The median dose for all case and control subjects was 3.2 mGy. The maximum estimated mean dose for any case or control was 29 +/- 5.6 mGy (a resident of Washington County, UT). Uncertainties were estimated for each estimated dose. The results of the dosimetry calculations were applied in an epidemiological analysis.

The Utah Thyroid Cohort Study: analysis of the dosimetry results

Above ground testing of nuclear weapons at the Nevada Test Site (NTS) during the 1950s created radioactive fallout that was dispersed into the atmosphere and deposited over a large geographical area of the U.S. One area believed to have received a considerable amount of exposure to radioiodines (131I and 133I) in the fallout was southwest Utah and southeast Nevada. This paper describes the estimates of doses to the thyroid for a cohort of 3,545 subjects who were children during the atmospheric testing period. This group of children was examined for thyroid disease during 1965-1970 and again in 1985-1986. The cohort was made up of children who lived in three counties in 1965: Washington County, Utah; Lincoln County, Nevada; and Graham County, Arizona (originally thought to be an unexposed group). Pathway analysis was used in the dosimetry, considering exposures through the ingestion of milk and vegetables, inhalation of iodine during the passage of the fallout cloud, and external exposure. Specific data were obtained on diet (including sources and levels of milk and vegetables consumed, residence history, and lifestyle) by interviewing the parents or nearest living relative of subjects. The final dosimetry file for each member of the cohort contained specific doses to the thyroid glands and uncertainties (reported as geometric standard deviations, GSD) related to each dose estimate. The mean absorbed dose to the thyroid for subjects living in Washington County, Utah, was 170 mGy; for Lincoln County, Nevada, 50 mGy; and for those living in Graham County, Arizona, 13 mGy. The maximum dose to any subject was 4,610 mGy. There were 10 subjects who had doses greater than 1 Gy. The majority of uncertainty values calculated in this study were GSD values between 2.0 and 4.0. The results of the dosimetry were combined with the results of clinical examinations of the cohort to determine if a causal relationship exists between dose to thyroid from NTS generated radioactive iodines and the incidence of thyroid disease.

A cohort study of thyroid disease in relation to fallout from nuclear weapons testing

OBJECTIVE

To estimate individual radiation doses and current thyroid disease status for a previously identified cohort of 4818 schoolchildren potentially exposed to fallout from detonations of nuclear devices at the Nevada Test Site between 1951 and 1958.

DESIGN

Cohort analytic study.

SETTING

Communities in southwestern Utah, southeastern Nevada, and southeastern Arizona.

PARTICIPANTS

Individuals who were still residing in the three-state area (n = 3122) were reexamined in 1985 and 1986, and information on the subjects' and their mothers' milk and vegetable consumption during the fallout period was obtained by telephone interview (n = 3545). After exclusions to eliminate missing data and confounding factors, 2473 subjects were available for analysis.

MAIN OUTCOME MEASURES

Individual radiation doses to the thyroid were estimated by combining consumption data with radionuclide deposition rates provided by the US Department of Energy and a survey of milk producers. Relative risk models adjusted for age, sex, and state were fitted using maximum likelihood to period prevalence data for thyroid carcinomas, neoplasms, and nodules.

RESULTS

Doses ranged from 0 mGy to 4600 mGy, and averaged 170 mGy in Utah. There was a statistically significant excess of thyroid neoplasms (benign and malignant; n = 19), with an increase in excess relative risk of 0.7% per milligray. A relative risk for thyroid neoplasms of 3.4 was observed among 169 subjects exposed to doses greater than 400 mGy. Positive but nonsignificant dose-response slopes were found for carcinomas and nodules.

CONCLUSIONS

Exposure to Nevada Test Site-generated radioiodines was associated with an excess of thyroid neoplasms. The conclusions are limited by the small number of exposed individuals and the low incidence of thyroid neoplasms.

Spatial cognition and neighborhood use: the relationship in older adults

Measures of spatial cognition, neighborhood knowledge, and neighborhood use from the research described by Walsh, Krauss, and Regnier (1981) were examined to determine if laboratory tests of spatial cognition were significant predictors of older adults' use of their neighborhoods. The overall results show that laboratory-based measures of spatial cognition and subjects' knowledge of their neighborhoods are both significant predictors of their use of neighborhood goods and services. The ability to learn and remember the location and orientation of objects, when contextual cues were not provided at test, was more predictive of the participants' neighborhood use than either the participants' number of years in the neighborhood or their mobility. Spatial memory as measured by the Educational Testing Service Building Memory task predicted neighborhood knowledge, which was predictive of neighborhood use.

Spatial cognition and neighborhood use: The relationship in older adults

Measures of spatial cognition, neighborhood knowledge, and neighborhood use from the research described by Walsh, Krauss, and Regnier (1981) were examined to determine if laboratory tests of spatial cognition were significant predictors of older adults' use of their neighborhoods. The overall results show that laboratory-based measures of spatial cognition and subjects' knowledge of their neighborhoods are both significant predictors of their use of neighborhood goods and services. The ability to learn and remember the location and orientation of objects, when contextual cues were not provided at test, was more predictive of the participants' neighborhood use than either the participants' number of years in the neighborhood or their mobility. Spatial memory as measured by the Educational Testing Service Building Memory task predicted neighborhood knowledge, which was predictive of neighborhood use.

Leukemia in Utah and radioactive fallout from the Nevada test site. A case-control study

Previous studies reported an association between leukemia rates and amounts of fallout in southwestern Utah from nuclear tests (1952 to 1958), but individual radiation exposures were unavailable. Therefore, a case-control study with 1177 individuals who died of leukemia and 5330 other deaths (controls) was conducted using estimates of dose to bone marrow computed from fallout deposition rates and subjects' residence locations. A weak association between bone marrow dose and all types of leukemia, all ages, and all time periods after exposure was found. This overall trend was not statistically significant, but significant trends in excess risk were found in subgroups defined by cell type, age, and time after exposure. The greatest excess risk was found in those individuals in the high-dose group with acute leukemia who were younger than 20 years at exposure and who died before 1964. These results are consistent with previous studies and with risk estimates for other populations exposed to radiation.

A cross-reactivity study of whole genomic DNA probes for Haemophilus actinomycetemcomitans, Bacteroides intermedius, and Bacteroides gingivalis

In this study, we evaluated the sensitivity and specificity of whole genomic DNA probes for the periodontal pathogens Haemophilus actinomycetemcomitans, Bacteroides intermedius, and Bacteroides gingivalis. By means of these probes, DNA hybridizations were performed against other organisms found in the oral cavity and organisms previously determined to be genetically similar. All three probes were sensitive to 10(3) cells for their respective organism. The H. actinomycetemcomitans probe cross-reacted with several haemophilus strains, Wolinella, and Campylobacter, indicating that H. actinomycetemcomitans-specific sequences would have to be identified and cloned for accurate detection of this organism in heterogeneous patient samples. Only very low levels of cross-reactivity were observed between the B. intermedius probe and representative black-pigmented Bacteroides. This low level of cross-reactivity did not interfere with the accurate identification of B. intermedius in sample evaluations. The B. gingivalis probe showed no cross-reactivity. Whole genomic probes will be used for the detection of B. intermedius and B. gingivalis in patient samples.