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PURPOSE: The Risk of Pediatric and Adolescent Cancer Associated with Medical Imaging (RIC) Study is quantifying the association between cumulative radiation exposure from fetal and/or childhood medical imaging and subsequent cancer risk. This manuscript describes the study cohorts and research methods. METHODS: The RIC Study is a longitudinal study of children in two retrospective cohorts from 6 U.S. healthcare systems and from Ontario, Canada over the period 1995–2017. The fetal-exposure cohort includes children whose mothers were enrolled in the healthcare system during their entire pregnancy and followed to age 20. The childhood-exposure cohort includes children born into the system and followed while continuously enrolled. Imaging utilization was determined using administrative data. Computed tomography (CT) parameters were collected to estimate individualized patient organ dosimetry. Organ dose libraries for average exposures were constructed for radiography, fluoroscopy, and angiography, while diagnostic radiopharmaceutical biokinetic models were applied to estimate organ doses received in nuclear medicine procedures. Cancers were ascertained from local and state/provincial cancer registry linkages. RESULTS: The fetal-exposure cohort includes 3,474,000 children among whom 6,606 cancers (2,394 leukemias) were diagnosed over 37,659,582 person-years; 0.5% had in utero exposure to CT, 4.0% radiography, 0.5% fluoroscopy, 0.04% angiography, 0.2% nuclear medicine. The childhood-exposure cohort includes 3,724,632 children in whom 6,358 cancers (2,372 leukemias) were diagnosed over 36,190,027 person-years; 5.9% were exposed to CT, 61.1% radiography, 6.0% fluoroscopy, 0.4% angiography, 1.5% nuclear medicine. CONCLUSION: The RIC Study is poised to be the largest study addressing risk of childhood and adolescent cancer associated with ionizing radiation from medical imaging, estimated with individualized patient organ dosimetry.

Objective: To determine whether selected features of the built environment can predict weight gain in a large longitudinal cohort of adults. Methods: Weight trajectories over a 5-year period were obtained from electronic health records for 115,260 insured patients aged 18–64 years in the Kaiser Permanente Washington health care system. Home addresses were geocoded using ArcGIS. Built environment variables were population, residential unit, and road intersection densities captured using Euclidean-based SmartMaps at 800-meter buffers. Counts of area supermarkets and fast food restaurants were obtained using network-based SmartMaps at 1,600, and 5,000-meter buffers. Property values were a measure of socioeconomic status. Linear mixed effects models tested whether built environment variables at baseline were associated with long-term weight gain, adjusting for sex, age, race/ethnicity, Medicaid insurance, body weight, and residential property values. Results: Built environment variables at baseline were associated with differences in baseline obesity prevalence and body mass index but had limited impact on weight trajectories. Mean weight gain for the full cohort was 0.06 kilograms at 1 year (95% CI: 0.03, 0.10); 0.64 kilograms at 3 years (95% CI: 0.59, 0.68), and 0.95 kilograms at 5 years (95% CI: 0.90, 1.00). In adjusted regression models, the top tertile of density metrics and frequency counts were associated with lower weight gain at 5 years follow-up compared to the bottom tertiles, though the mean differences in weight change for each follow-up year (1, 3, and 5) did not exceed 0.5 kilograms. Conclusion: Built environment variables that were associated with higher obesity prevalence at baseline had limited independent obesogenic power with respect to weight gain over time. Residential unit density had the strongest negative association with weight gain. Future work on the influence of built environment variables on health should also examine social context, including residential segregation and residential mobility.

OBJECTIVE: A retrospective cohort study investigated the association between having surgery and risk of mortality for up to five years and if this association was modified by incident End Stage Renal Disease (ESRD) during the follow-up period. SUMMARY BACKGROUND DATA: Mortality risk in individuals with pre-dialysis chronic kidney disease (CKD) is high and few effective treatment options are available. Whether bariatric surgery can improve survival in people with CKD is unclear. METHODS: Patients with class II and III obesity and pre-dialysis CKD stages 3 – 5 who underwent bariatric surgery between 1/1/2006 and 9/30/2015 (n = 802) were matched to patients who did not have surgery (n = 4,933). Mortality was obtained from state death records and ESRD was identified through state-based or healthcare system-based registries. Cox regression models were used to investigate the association between bariatric surgery and risk of mortality and if this was moderated by incident ESRD during the follow-up period. RESULTS: Patients were primarily women (79%), non-Hispanic White (72%), under 65 years old (64%), who had a BMI ≥ 40 kg/m(2) (59%), diabetes (67%) and hypertension (89%). After adjusting for incident ESRD, bariatric surgery was associated with a 79% lower 5-year risk of mortality compared to matched controls (HR = 0.21; 95% CI: 0.14-0.32; p < .001). Incident ESRD did not moderate the observed association between surgery and mortality (HR = 1.59; 95% CI 0.31-8.23; p = .58). CONCLUSIONS: Bariatric surgery is associated with a reduction in mortality in pre-dialysis patients regardless of developing ESRD. These findings are significant because patients with CKD are at relatively high risk for death with few efficacious interventions available to improve survival.

To explore the built environment (BE) and weight change relationship by age, sex, and racial/ethnic subgroups in adults.Weight trajectories were estimated using electronic health records for 115,260 insured Kaiser Permanente Washington members age 18-64 years. Member home addresses were geocoded using ArcGIS. Population, residential, and road intersection densities and counts of area supermarkets and fast food restaurants were measured with SmartMaps (800 and 5000-meter buffers) and categorized into tertiles. Linear mixed-effect models tested whether associations between BE features and weight gain at 1, 3, and 5 years differed by age, sex, and race/ethnicity, adjusting for demographics, baseline weight, and residential property values.Denser urban form and greater availability of supermarkets and fast food restaurants were associated with differential weight change across sex and race/ethnicity. At 5 years, the mean difference in weight change comparing the 3rd versus 1st tertile of residential density was significantly different between males (-0.49 kg, 95% CI: -0.68, -0.30) and females (-0.17 kg, 95% CI: -0.33, -0.01) (P-value for interaction = 0.011). Across race/ethnicity, the mean difference in weight change at 5 years for residential density was significantly different among non-Hispanic (NH) Whites (-0.47 kg, 95% CI: -0.61, -0.32), NH Blacks (-0.86 kg, 95% CI: -1.37, -0.36), Hispanics (0.10 kg, 95% CI: -0.46, 0.65), and NH Asians (0.44 kg, 95% CI: 0.10, 0.78) (P-value for interaction0.001). These findings were consistent for other BE measures.The relationship between the built environment and weight change differs across demographic groups. Careful consideration of demographic differences in associations of BE and weight trajectories is warranted for investigating etiological mechanisms and guiding intervention development.

Background Children with central nervous system (CNS) tumors undergo frequent imaging for diagnosis and follow-up, but few studies have characterized longitudinal imaging patterns. We described medical imaging in children before and after malignant CNS tumor diagnosis. Procedure We conducted a retrospective cohort study of children aged 0–20 years diagnosed with CNS tumors between 1996–2016 at six U.S. integrated healthcare systems and Ontario, Canada. We collected computed topography (CT), magnetic resonance imaging (MRI), radiography, ultrasound, nuclear medicine examinations from 12 months before through 10 years after CNS diagnosis censoring six months before death or a subsequent cancer diagnosis, disenrollment from the health system, age 21 years, or December 31, 2016. We calculated imaging rates per child per month stratified by modality, country, diagnosis age, calendar year, time since diagnosis, and tumor grade. Results We observed 1,879 children with median four years follow-up post-diagnosis in the U.S. and seven years in Ontario, Canada. During the diagnosis period (±15 days of diagnosis), children averaged 1.10 CTs (95% confidence interval [CI] 1.09–1.13) and 2.14 MRIs (95%CI 2.12–2.16) in the U.S., and 1.67 CTs (95%CI 1.65–1.68) and 1.86 MRIs (95%CI 1.85–1.88) in Ontario. Within one year after diagnosis, 19% of children had ≥5 CTs and 45% had ≥5 MRIs. By nine years after diagnosis, children averaged one MRI and one radiograph per year with little use of other imaging modalities. Conclusions MRI and CT are commonly used for CNS tumor diagnosis, whereas MRI is the primary modality used during surveillance of children with CNS tumors.

Objective To investigate weight trajectories among patients with severe obesity undergoing sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and nonsurgical treatment. Background Although bariatric procedures are associated with substantial weight loss, few studies have compared surgical outcomes to nonsurgical treatment, particularly for SG. Methods In this retrospective, matched cohort study, adult patients with body mass index ≥35 kg/m who underwent RYGB or SG procedures from January 2005 through September 2015 were matched to 87,965 nonsurgical patients. Hierarchical linear models were used to investigate percent total weight loss (%TWL) and regain at 5 years among RYGB, SG, and nonsurgical patients, and at 10 years for RYGB and nonsurgical patients. Results Among 13,900 SG, 17,258 RYGB, and 87,965 nonsurgical patients, the 5-year follow-up rate was 70.9%, 72.0%, and 64.5%, respectively. At 1 year, RYGB patients had 28.4%TWL (95% confidence interval: 28.2, 28.5), SG 23.0%TWL (22.8, 23.2), and nonsurgical patients 0.2%TWL (0.1, 0.4). At 5 years, RYGB had 21.7%TWL (21.5, 22.0), SG 16.0%TWL (15.4, 16.6), and nonsurgical patients 2.2%TWL (2.0, 2.5). After 5 years, 3.7% of RYGB and 10.1% of SG patients had regained weight to within 5% of baseline. At 10 years, RYGB patients had 20.2%TWL (19.3, 21.0) and nonsurgical patients 4.8%TWL (4.0, 5.5). Conclusions In this study, patients with severe obesity who underwent SG and RYGB lost significantly more weight at 5 years than nonsurgical patients. Weight regain was common after surgery but regain to within 5% of baseline was rare.

Purpose Safe firearm storage practices are associated with a lower risk of self-inflicted injury and death. Whether such practices and relevant beliefs differ between households of adolescents with and without mental illness is unknown. Methods We used survey and administrative data to perform a two-stage cross-sectional study of parents/guardians of adolescents who were 11–17 years, enrolled in a managed care plan in 2004 and living in a household with a firearm. Multivariable Poisson models compared the prevalence of three firearm storage practices between households of adolescents with (depression or bipolar disorder) and without mental illness (no psychiatric or substance use disorder), including whether all firearms were locked, any firearms were loaded, and all firearms were locked and unloaded. We used chi-square tests to compare responses to Likert items assessing beliefs relevant to storage practices between households. Results Adolescents with mental illness were present in 141 (50.5%) of 279 study households. Their mean age was 14.5 years, and 54.8% were male. The mean age of parent/guardian respondents was 47.0 years, and 17.9% were male. Respondents from nearly 70% of households reported that all household firearms were stored locked and unloaded. In unadjusted and adjusted analyses, there were no significant differences in the prevalence of three firearm storage practices or in beliefs relevant to those practices between households of adolescents with and without mental illness. Conclusions These findings add to a growing body of evidence suggesting that firearm storage practices do not differ based on household mental health risk factors for self-harm.

OBJECTIVE To identify and quantify any legacy effect of bariatric surgery on risk of incident microvascular disease in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS We conducted a retrospective observational cohort study (n = 4,683; 40% racial/ethnic minority) of patients with type 2 diabetes who underwent bariatric surgery from 2001 through 2011. The primary outcome measure was incident microvascular disease defined as a composite indicator of the first occurrence of retinopathy, neuropathy, and/or nephropathy. The Cox proportional hazards framework was used to investigate the associations between type 2 diabetes remission/relapse status and time to microvascular disease. RESULTS Covariate-adjusted analyses showed that patients who experienced type 2 diabetes remission had 29% lower risk of incident microvascular disease compared with patients who never remitted (hazard ratio [HR] 0.71 [95% CI 0.60, 0.85]). Among patients who experienced a relapse after remission, the length of time spent in remission was inversely related to the risk of incident microvascular disease; for every additional year of time spent in remission prior to relapse, the risk of microvascular disease was reduced by 19% (HR 0.81 [95% CI 0.67, 0.99]) compared with patients who never remitted. CONCLUSIONS Our results indicate that remission of type 2 diabetes after bariatric surgery confers benefits for risk of incident microvascular disease even if patients eventually experience a relapse of their type 2 diabetes. This provides support for a legacy effect of bariatric surgery, where even a transient period of surgically induced type 2 diabetes remission is associated with lower long-term microvascular disease risk.

Although all weight-loss approaches may improve insulin sensitivity in type 2 diabetes, bariatric surgery is believed to be the only reliable means of achieving diabetes remission. We conducted a retrospective cohort study to compare rates of diabetes remission, relapse and all-cause mortality among severely obese individuals with diabetes who underwent bariatric surgery versus nonsurgically treated individuals. Severely obese adults with uncontrolled or medication-controlled diabetes who underwent bariatric surgery or received usual medical care from 2005 to 2008 in three health care delivery systems in the United States were eligible. Diabetes status was identified using pharmacy, laboratory, and diagnosis information from electronic medical records. A propensity approach and exclusion criteria identified 1395 adults with diabetes who had bariatric surgery and 62322 who did not. Most procedures were Roux-en-Y gastric bypass (72.0% laparoscopic; 8.2% open); 4.4% were gastric banding, 2.4 % sleeve gastrectomy, and 13.2% were other procedures. At two years, bariatric subjects experienced significantly higher diabetes remission rates [73.7% (95% CI: 70.6, 76.5)] compared to nonsurgical subjects [6.9% (95%CI: 6.9, 7.1)]. Age, site, duration of diabetes, hemoglobin A1c level, and intensity of diabetes medication treatment were significantly associated with remission. Bariatric subjects also experienced lower relapse rates than nonsurgical subjects (adjusted HR: 0.19; 95% CI: 0.15 to 0.23) with no higher risk of death (adjusted HR: 0.54; 95% CI: 0.22 to 1.30). We conclude that bariatric surgery can effectively induce remission of diabetes among most severely obese adults, and this treatment approach appears to be superior to nonsurgical treatment in inducing diabetes remission.

Gastric bypass has profound effects on glycemic control in adults with type 2 diabetes mellitus. The goal of this study was to examine the long-term rates and clinical predictors of diabetes remission and relapse among patients undergoing gastric bypass.We conducted a retrospective cohort study of adults with uncontrolled or medication-controlled type 2 diabetes who underwent gastric bypass from 1995 to 2008 in three integrated health care delivery systems in the USA. Remission and relapse events were defined by diabetes medication use and clinical laboratory measures of glycemic control. We identified 4,434 adults with uncontrolled or medication-controlled type 2 diabetes who had gastric bypass.Overall, 68.2 % (95 % confidence interval [CI], 66 and 70 %) experienced an initial complete diabetes remission within 5 years after surgery. Among these, 35.1 % (95 % CI, 32 and 38 %) redeveloped diabetes within 5 years. The median duration of remission was 8.3 years. Significant predictors of complete remission and relapse were poor preoperative glycemic control, insulin use, and longer diabetes duration. Weight trajectories after surgery were significantly different for never remitters, relapsers, and durable remitters (p = 0.03).Gastric bypass surgery is associated with durable remission of type 2 diabetes in many but not all severely obese diabetic adults, and about one third experience a relapse within 5 years of initial remission. More research is needed to understand the mechanisms of diabetes relapse, the optimal timing of surgery in effecting a durable remission, and the relationship between remission duration and incident microvascular and macrovascular events.

BACKGROUND Bias due to missing data is a major concern in electronic health record (EHR)-based research. As part of an ongoing EHR-based study of weight change among patients treated for depression, we conducted a survey to investigate determinants of missingness in the available weight information and to evaluate the missing-at-random assumption. METHODS We identified 8,345 individuals enrolled in a large EHR-based health care system who had monotherapy treatment for depression from April 2008 to March 2010. A stratified sample of 1,153 individuals completed a detailed survey. Logistic regression was used to investigate determinants of whether a patient (1) had an opportunity to be weighed at treatment initiation (baseline), and (2) had a weight measurement recorded. Parallel analyses were conducted to investigate missingness during follow-up. Throughout, inverse-probability weighting was used to adjust for the design and survey nonresponse. Analyses were also conducted to investigate potential recall bias. RESULTS Missingness at baseline and during follow-up was associated with numerous factors not routinely collected in the EHR including whether or not the patient had ever chosen not to be weighed, external weight control activities, and self-reported baseline weight. Patient attitudes about their weight and perceptions regarding the potential impact of their depression treatment on weight were not related to missingness. CONCLUSION Adopting a comprehensive strategy to investigate missingness early in the research process gives researchers information necessary to evaluate key assumptions. While the survey presented focuses on outcome data, the overarching strategy can be applied to any and all data elements subject to missingness.

Summary Objective We conducted this study to investigate the rate of clinically important, extreme weight gain (EWG; ≥7% body weight gain) among all second generation antipsychotic (SGA) users in two large health care systems in the United States. Study design Retrospective observational cohort study. Methods We used electronic medical record databases of two health systems to identify adults aged 18–79 years who from 1 January 2004 to 31 December 2011 had initiated a SGA medication. All patients had to have a minimum of two weight measures in the medical record: (1) one or more weights in the 180-day pre-treatment (baseline) period; and (2) one or more weights in the first year after initiating SGA treatment. Results We found that EWG occurred in 7.7–17.0% of SGA users. At one year, the average weight gain was nearly 10kg among SGA users who experienced EWG. Olanzapine was the SGA most commonly associated with EWG with a rate of 17.0 per 100 users [95% confidence interval (CI): 14.2–20.5], while ziprasidone was least commonly associated with EWG (7.7 per 100 users; 95% CI: 4.6–13.0). Conclusions We found that clinically-important weight gain was common after the initiation of SGA treatment, and the EWG phenotype was easily identifiable within electronic medical records. There was significant heterogeneity in the rate of EWG across SGA medications. Weight gains of this magnitude are likely to have adverse health consequences and there is a significant unmet opportunity for physicians to identify these events and mitigate the harms of SGA use.

This population-based case-control study examined the risk of multiple myeloma in relation to socioeconomic status. Subjects included 689 cases with newly diagnosed multiple myeloma during 1977-1981 from four U.S. populations and 1,680 controls selected from residents of these same populations. We collected lifetime occupational histories and coded them according to the 1970 Duncan Socioeconomic Index and Nam-Powers Socioeconomic Status scores. We classified scores for the occupations held the longest, highest ever held, and held most recently into quartiles based on the distribution among controls. After adjusting for age group, race, and study site, risk of multiple myeloma was inversely associated with socioeconomic status scores in both men and women. Risk among persons in the lowest quartile of scores was 63% higher (95% confidence interval 21%-119%) than that among those in the highest quartile when the highest Nam-Powers score was used. Similar trends were evident for all three methods of classifying occupational history and for both Duncan and Nam-Power scores. These results changed little after removing from analyses occupations previously associated with increased risk. The occupation-based scores were stronger predictors of risk than years of education. As a proxy measure of occupational, environmental, or life-style factors, socioeconomic status may be a clue to etiologic factors for multiple myeloma.

Research on inflammatory bowel disease risk among oral contraceptive users has reached conflicting conclusions. This population-based case-control study evaluated the effects of oral contraceptive use on ulcerative colitis and Crohn's disease risk. Cases were women enrollees, aged 15-68 years, of Group Health Cooperative of Puget Sound (a prepaid health plan based in western Washington State) who had ulcerative colitis (n = 211) or Crohn's disease (n = 91). Age-matched controls were randomly selected from the health plan enrollment file. An in-person interview obtained information about lifetime contraceptive use. Conditional logistic regression analysis was used to estimate relative risks and 95% confidence intervals for disease. Women who reported oral contraceptive use within 6 months before disease onset were at increased risk for both diseases compared with never users (relative risk (RR) of ulcerative colitis = 2.0, 95% confidence interval (CI) 1.2-3.3; RR of Crohn's disease = 2.6, 95% CI 1.2-5.5). Women who had used oral contraceptives for more than 6 years had the highest risk of Crohn's disease (RR = 5.1, 95% CI 1.8-14.3). In contrast, increasing duration of use was not associated with increased risk of ulcerative colitis. Adjustment for race, smoking, income, or pregnancy history did not substantially alter these results. Higher ulcerative colitis risk tended to occur among users of high estrogen dose oral contraceptives, while Crohn's disease risk was similar regardless of estrogen potency.

Our objectives were to describe the prevalence of periodontal care (a marker of periodontitis) among persons with and without diabetes and to examine the association between periodontal care and diabetes.We conducted a cross-sectional analysis, using 5 years of electronic data from a population-based cohort (N = 46,132), aged 40 to 70 years, with dental and medical insurance, and ≥ 1 dental and ≥ 1 medical visit. Periodontal care (yes/no) was defined by dental claims codes for procedures used to manage periodontitis. The association between periodontal care and diabetes was determined using logistic regression adjusted for and stratified by age, sex, insurance type, smoking status, body mass index (BMI) (in kilograms per square meter), and resource utilization band (RUB) (a measure of expected health care utilization attributable to comorbidity).Overall, 11.2% (5,153 of 46,132) met diabetes criteria. The age-adjusted prevalence of periodontal care among those with and without diabetes was 39.1% and 32.5%, respectively (P0.0001). The association between diabetes and periodontal care decreased with increasing age (interaction, P0.0001), adjusting for BMI and RUB. The aged-stratified, adjusted odds ratio (OR) for periodontal care associated with diabetes was highest among those aged 40 to 44 years [OR, 1.6; confidence interval (CI), 1.30 to 1.97] and lowest among those aged 60 to 64 years (OR, 0.97; CI, 0.81 to 1.15) and was significant only among those aged 40 to 54 years.We found that the prevalence of periodontal care was significantly higher among those with diabetes compared to those without diabetes and that the magnitude of this association decreased with increasing age.

To link the administrative data of a large dental carrier and an integrated health plan in Washington State to conduct an observational study of diabetes and periodontal disease.Evaluation of variable suitability, testing of linkage variables, and performing an n - 1 deterministic linkage strategy.We examined a variety of administrative data variables for their consistency over time and their information richness to use as matching variables. After choosing social security number, date of birth, first name, and last name, we tested their reliability as linking variables among a population with dual dental and medical insurance. Lastly, we performed four n - 1 deterministic linkage steps to obtain our study population.With a success match rate of more than 96% with the 4 test variables, we extracted the entire population who met the study criteria with the understanding that only a subset would successfully link. We linked 78,230 individuals (55.2% of the Group Health Cooperative population). Of these matches more than 50% occurred within a last name-first name-birth date deterministic match.Employer groups who provide dental-medical benefits for their employees send identical administrative data to dental and healthcare plans. The n - 1 deterministic linkage was accomplished by using a relatively straightforward approach because these data were fairly homogeneous and of high quality. Until medical care and dental care are integrated, it is possible to link these data to assess the impact of oral disease on overall health.

• Objective. —Acute mountain sickness has been described in adults but little is known concerning its occurrence in children. Our objective was to determine the incidence of acute mountain sickness in children. Methods. —A survey questionnaire was completed by 558 children (aged 9 to 14 years) after they ascended from 1600 to 2835 m and from 405 similarly aged children after travel at sea level. Results. —Three or more of the following symptoms in the high-altitude setting were considered as the case definition of acute mountain sickness: headache, loss of appetite, vomiting, fatigue, insomnia, shortness of breath, and dizziness. One hundred fifty-six (28%) of the children at 2835 m developed acute mountain sickness. Three or more symptoms developed in a smaller, but nonetheless considerable, number (86 [21%]) of children at sea level. Headache, shortness of breath, and dizziness were reported more frequently at high altitude than at low altitude, whereas the other symptoms occurred with equal frequency at the two locations. Conclusions. —More than one fourth of the children visiting high altitude developed acute mountain sickness. A high proportion (21%) of children at sea level developed similar symptoms, suggesting that an appreciable portion of the symptoms present were due to factors other than altitude, such as travel, anxiety, or disruption of daily routine. ( AJDC . 1993;147:143-145)