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Animal experiment findings suggest that high doses of ionizing radiation exposure (>1.0 Gy) may cause genetic and epigenetic effects in offspring. However, epidemiological studies of offspring of radiation-exposed parents did not find increased risks of any health effects. Findings of cellular/experimental investigations and studies of human health effects are contradicting, and further investigations are needed to help resolve ambiguities using updated and/or improved data. This paper provides a detailed description of a database of families of workers of the first Russian nuclear facility, Mayak Production Association, located in the Southern Urals in the Chelyabinsk region close to Ozyorsk city, which started its operation in 1948 and today consists of reactors, radiochemical and plutonium production plants, and auxiliary facilities. The Mayak worker cohort includes 22,377 individuals (25% females) who were hired at one of the main Mayak PA facilities between 1948 and 1982 and were externally or internally exposed to ionizing radiation over prolonged periods. Advantages of the cohort include its large size, extensive follow-up period (70 y), individually measured doses from external and internal exposure and the wide range of these doses, heterogeneity by gender/age/ethnicity/initial health status, complete data on vital status and causes of death, available medical information on morbidity and reproduction, available data on non-radiation factors, and stored biological specimens donated by more than one-third of the cohort members. Based on medical and dosimetry database "Clinics" containing raw data on workers of the study cohort, the Mayak workers' family and offspring database was created. To date, it comprises 12,195 family couples (a husband and a wife) and 16,585 offspring. Biological specimens are available for more than 1,000 family triads (a husband, a wife, and their child). Stages of assembling the database and its descriptive characteristics are presented in this paper. Examples of potential applications of the database for investigations of non-targeted and transgenerational radiation effects in offspring of exposed parents are discussed.

OBJECTIVES To update the U.S. portion of an historical cohort mortality study of workers with potential exposure to chloroprene (CD) and vinyl chloride (VC) with focus on lung and liver cancer. METHODS Subjects were 6864 workers from two sites with vital status determined through 2017 for 99% of subjects and cause of death for 97.2% of deaths. Historical exposures to CD and VC were estimated quantitatively. We performed external and internal mortality comparisons. RESULTS External comparisons revealed mostly deficits in deaths; internal comparisons revealed no consistent evidence of exposure-response relationships with CD or VC. CONCLUSIONS Our update continues to support the conclusion that the risk of death from lung or liver cancer is unrelated to exposure to CD or VC at levels experienced by workers in the two U.S. sites.

The high cost of critical care has engendered research into identifying influential factors. However, existing studies have not considered patient vital status at ICU discharge. This study sought to determine the effect of mortality upon the total cost of an ICU stay.Retrospective cohort study.Twenty-six ICUs at 13 hospitals in the United States.58,344 admissions from January 1, 2012, to June 30, 2016, obtained from a commercial ICU database.None.The median observed cost of a unit stay was $9,619 (mean = $16,353). A multivariable regression model was developed on the log of total costs for a unit stay, using severity of illness, unit admitting diagnosis, mortality in the unit, daily unit occupancy (occupying a bed at midnight), and length of mechanical ventilation. This model had an r of 0.67 and a median difference between observed and expected costs of $437. The first few days of care and the first day receiving mechanical ventilation had the largest effect on total costs. Patients dying before unit discharge had 12.4% greater costs than survivors (p0.01; 99% CI = 9.3-15.5%) after multivariable adjustment. This effect was most pronounced for patients with an extended ICU stay who were receiving mechanical ventilation.While the largest drivers of ICU costs at the patient level are day 1 room occupancy and day 1 mechanical ventilation, mortality before unit discharge is associated with substantially higher costs. The increase was most evident for patients with an extended ICU stay who were receiving mechanical ventilation. Studies evaluating costs among ICUs need to take mortality into account.

OBJECTIVE To evaluate mortality rates among a cohort of jet engine manufacturing workers. METHODS Subjects were 222,123 workers employed from 1952 to 2001. Vital status was determined through 2004 for 99% of subjects and cause of death for 95% of 68,317 deaths. We computed standardized mortality ratios and modeled internal cohort rates. RESULTS Mortality excesses reported initially no longer met the criteria for further investigation. We found two chronic obstructive pulmonary disease-related mortality excesses that met the criteria in two of eight study plants. CONCLUSIONS At the total cohort level, chronic obstructive pulmonary disease-related categories were not related to any factors or occupational exposures considered. A full evaluation of these excesses was limited by lack of data on smoking history. Occupational exposures received outside of work or uncontrolled positive confounding by smoking cannot be ruled out as reasons for these excesses.

Background The long‐term outcomes of patients undergoing interventions for congenital heart disease ( CHD ) remain largely unknown. We linked the Pediatric Cardiac Care Consortium ( PCCC ) with the National Death Index ( NDI ) and the United Network for Organ Sharing Dataset ( UNOS ) registries to study mortality and transplant occurring up to 32 years postintervention. The objective of the current analysis was to determine the sensitivity of this linkage in identifying patients who are known to have died or undergone heart transplant. Methods and Results We used direct identifiers from 59 324 subjects registered in the PCCC between 1982 and 2003 to test for completeness of case ascertainment of subjects with known vital and heart transplant status by linkage with the NDI and UNOS registries. Of the 4612 in‐hospital deaths, 3873 were identified by the NDI as “true” matches for a sensitivity of 84.0% (95% CI, 82.9–85.0). There was no difference in sensitivity across 25 congenital cardiovascular conditions after adjustment for age, sex, race, presence of first name, death year, and residence at death. Of 455 known heart transplants in the PCCC , there were 408 matches in the UNOS registry, for a sensitivity of 89.7% (95% CI , 86.9–92.3). An additional 4851 deaths and 363 transplants that occurred outside the PCCC were identified through 2014. Conclusions The linkage of the PCCC with the NDI and UNOS national registries is feasible with a satisfactory sensitivity. This linkage provides a conservative estimate of the long‐term death and heart transplant events in this cohort.

The objective of this study was to identify the vital status and reasons for children becoming loss to follow-up (LTFU) from a large program in western Kenya.This was a prospective evaluation of a random sample of 30% of HIV-exposed and HIV-positive children LTFU from either an urban or rural HIV Academic Model Providing Access to Healthcare clinic. LTFU is defined as absence from clinic for6 months if on combination antiretroviral therapy and12 months if not. Experienced community health workers were engaged to locate them.There were 97 children sampled (78 urban, 19 rural). Of these, 82% were located (78% urban, 100% rural). Among the HIV positive, 16% of the children were deceased, and 16% had not returned to clinic because of disclosure issues/discrimination in the family or community. Among the HIV exposed, 30% never returned to care because their guardians either had not disclosed their own HIV status or were afraid of family/community stigma related to their HIV status or that of the child. Among children whose HIV status was unknown, 29% of those found had actually died, and disclosure/discrimination accounted for 14% of the reasons for becoming LTFU. Other reasons included believing the child was healed by faith or through the use of traditional medicine (7%), transport costs (6%), and transferring care to other programs or clinics (8%).After locating80% of the children in our sample, we identified that mortality and disclosure issues including fear of family or community discrimination were the most important reasons why these children became LTFU.

Background: Poor access to or inadequate health insurance contributes to disparities in cancer incidence and mortality. Cancer registry “payer source” data is collected by many cancer registries in the United States and has been used to compare cancer outcomes across insurance types. Objectives: We evaluated the validity of cancer registry data on patient Medicaid status against enrollment data from Medi-Cal, California's Medicaid program. Methods: Data from the statewide California Cancer Registry for persons under age 65 years diagnosed with 1) any cancer in 1998 and 1999 or 2) with invasive cervical cancer between 1996 and 1999 were obtained and linked probabilistically to Medi-Cal enrollment files. We compared registry Medicaid status, determined from payer source information, against linkage results and used crosstabulations to calculate sensitivity, specificity, and positive predictive value. These measures were compared across different hospital and patient characteristics and cancer types. Results: Cancer registry Medicaid status data had poor sensitivity (48%), good specificity (98%), and moderate positive predictive value (77%). Measures of validity did not vary substantially by cancer type, stage, patient age, sex, vital status, race/ethnicity, socioeconomic status, or diagnosing hospital size. Registry data undercounted the number of Medicaid patients by 52% and incorrectly assigned Medicaid as a payer to approximately 2% of patients. Conclusions: As a result of the poor validity of cancer registry Medicaid status data, caution should be used when interpreting cancer outcomes by insurance type calculated from registry payer source data. Linkage of registry data to Medicaid enrollment files represents a more accurate means of identifying Medicaid insurance status.

Objective: The objective of this study was to identify the determinants of 30-day postoperative mortality and long-term survival after major surgery as exemplified by 8 common operations. Background Data: The National Surgical Quality Improvement Program (NSQIP) database contains pre-, intra-, and 30-day postoperative data, prospectively collected in a standardized fashion by a dedicated nurse reviewer, on major surgery in the Veterans Administration (VA). The Beneficiary Identification and Records Locator Subsystem (BIRLS) is a VA file that depicts the vital status of U.S. veterans with 87% to 95% accuracy. Methods: NSQIP data were merged with BIRLS to determine the vital status of 105,951 patients who underwent 8 types of operations performed between 1991 and 1999, providing an average follow up of 8 years. Logistic and Cox regression analyses were performed to identify the predictors of 30-day mortality and long-term survival, respectively. Results: The most important determinant of decreased postoperative survival was the occurrence, within 30 days postoperatively, of any one of 22 types of complications collected in the NSQIP. Independent of preoperative patient risk, the occurrence of a 30-day complication in the total patient group reduced median patient survival by 69%. The adverse effect of a complication on patient survival was also influenced by the operation type and was sustained even when patients who did not survive for 30 days were excluded from the analyses. Conclusions: The occurrence of a 30-day postoperative complication is more important than preoperative patient risk and intraoperative factors in determining the survival after major surgery in the VA. Quality and process improvement in surgery should be directed toward the prevention of postoperative complications.

In HIV cohorts in sub-Saharan Africa, documenting vital status of patients lost to follow-up is a major challenge. The effect of specific vital status investigation procedures (VSIPs) on the number of known deaths has never been shown. We assessed the effects of VSIP on survival estimates in a 4-year prospective cohort study in Abidjan, Côte d'Ivoire. As of June 2000, 545 HIV-infected adults had been followed for 1186 person-years, of whom 233 were documented as deceased. Forty-eight percent of deaths were known through scheduled VSIPs, including reading of the newspaper obituaries (2%), telephone calls to relatives (10%), and home visits (36%). Survival probability at 1, 2, and 3 years was estimated to be 0.79, 0.65, and 0.56, respectively. Without VSIP, survival at 1, 2, and 3 years would have been estimated to be 11, 23, and 30% higher, respectively. In this large African capital city, survival estimates closely depended on VSIPs, mainly home visits. We suggest that the percentage of deaths known through VSIPs would be a useful indicator to be added when reporting survival data from urban HIV cohort studies in sub-Saharan Africa.

To the Editor: We read with interest the article by Baldereschi et al. on the effect of dementia in predicting death among Italian elderly.1 We have pertinent data on 24 and 60 months’ mortality rate obtained in a multidimensional study conducted in Italy in 1992 on a community-dwelling population 70 years of age and older.2 All institutionalized subjects were excluded. At baseline (1992), valid questionnaires assessing demographics, mental status, chronic conditions, and functional and social status were available for 549 persons (89.6% of the eligible population). Vital status and time of death 2 (1994) and 5 years (1997) after the baseline evaluation was ascertained by telephoning patients and caregivers. The mean age of the 549 persons (179 men and 370 women) was 76.9 ± 5.4 years. They had 4.6 ± 2.0 years of education; they were affected by 3.5 …

A study of the completeness of death ascertainment through the Social Security Administration (SSA) was undertaken. Groups of subjects of known vital status were submitted by the Los Alamos National Laboratory to the SSA for a mortality record search. Correctly ascertained deaths ranged from 77% to 90% among males and from 53% to 76% among females. A duplicate record search one year later raised correct ascertainment to 88% to 94% of male deaths and to 73% to 87% of female deaths. Death ascertainment appeared to be independent of ethnicity (Anglo and Hispanic), cause of death, location of death, and year of death. Age at time of death was strongly related to death ascertainment. Individuals 65 years of age and over were identified much more accurately than persons less than 65 years of age. Lack of incentive to report deaths of persons under retirement age is believed to be responsible. The age of an industrial facility and of the work force may have a major influence on the adequacy of mortality ascertainment through social security.

The relationship between baseline symptom reports and subsequent mortality over a 24-year period was examined in a group of 1,224 white male nonsupervisory paper workers. Symptom reports were measured via the Cornell Medical Index, and the vital status of each participant was ascertained by reviewing company personnel records and death certificates. Analyses based on proportional hazards models suggest that symptom reports are predictive of mortality (RR = 1.24; P = .0002), independent of the participant's age and biologic risk status at intake. Analyses based upon age-specific and age-standardized mortality ratios confirm that the paper workers were subject to a "healthy worker effect" (standardized mortality ratio [SMR] = 0.66), and that the healthy worker effect is attenuated (SMR = 0.77) among those participants reporting ten or more symptoms at the beginning of the follow-up period.

When 10,766 members of a refinery retrospective cohort study were assessed for vital status using conventional company and Social Security Administration records, the status of 370 remained unknown. Computerized corporate files of shareholder information yielded current addresses for 243 of those lost to follow-up, and through Directory Assistance, telephone numbers were obtained for 152. Vital status was ascertained by telephone for 146 of the 370 members of the cohort whose status had been unknown.