Browsing by Subject "Population Groups"

Now showing 1 - 5 of 5
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    A dimensional approach to understanding severity estimates and risk correlates of marijuana abuse and dependence in adults.
    (International journal of methods in psychiatric research, 2012-06) Wu, Li-Tzy; Woody, George E; Yang, Chongming; Pan, Jeng-Jong; Reeve, Bryce B; Blazer, Dan G
    While item response theory (IRT) research shows a latent severity trait underlying response patterns of substance abuse and dependence symptoms, little is known about IRT-based severity estimates in relation to clinically relevant measures. In response to increased prevalences of marijuana-related treatment admissions, an elevated level of marijuana potency, and the debate on medical marijuana use, we applied dimensional approaches to understand IRT-based severity estimates for marijuana use disorders (MUDs) and their correlates while simultaneously considering gender- and race/ethnicity-related differential item functioning (DIF). Using adult data from the 2008 National Survey on Drug Use and Health (N = 37,897), Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for MUDs among past-year marijuana users were examined by IRT, logistic regression, and multiple indicators-multiple causes (MIMIC) approaches. Among 6917 marijuana users, 15% met criteria for a MUD; another 24% exhibited subthreshold dependence. Abuse criteria were highly correlated with dependence criteria (correlation = 0.90), indicating unidimensionality; item information curves revealed redundancy in multiple criteria. MIMIC analyses showed that MUD criteria were positively associated with weekly marijuana use, early marijuana use, other substance use disorders, substance abuse treatment, and serious psychological distress. African Americans and Hispanics showed higher levels of MUDs than Whites, even after adjusting for race/ethnicity-related DIF. The redundancy in multiple criteria suggests an opportunity to improve efficiency in measuring symptom-level manifestations by removing low-informative criteria. Elevated rates of MUDs among African Americans and Hispanics require research to elucidate risk factors and improve assessments of MUDs for different racial/ethnic groups.
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    Caring for Alaska Native prostate cancer survivors in primary care: a survey of Alaska Tribal Health System providers.
    (Int J Circumpolar Health, 2014) Tilburt, Jon C; Kelley, Stacy; DeCourtney, Christine A; Humeniuk, Katherine M; Latini, Jerilyn; Kim, Simon P
    BACKGROUND: Little is known about the constraints of optimizing health care for prostate cancer survivors in Alaska primary care. OBJECTIVE: To describe the experiences and attitudes of primary care providers within the Alaska Tribal Health System (ATHS) regarding the care of prostate cancer survivors. DESIGN: In late October 2011, we emailed a 22-item electronic survey to 268 ATHS primary care providers regarding the frequency of Prostate Specific Antigen (PSA) monitoring for a hypothetical prostate cancer survivor; who should be responsible for the patient's life-long prostate cancer surveillance; who should support the patient's emotional and medical needs as a survivor; and providers' level of comfort addressing recurrence monitoring, erectile dysfunction, urinary incontinence, androgen deprivation therapy, and emotional needs. We used simple logistic regression to examine the association between provider characteristics and their responses to the survivorship survey items. RESULTS: Of 221 individuals who were successfully contacted, a total of 114 responded (52% response rate). Most ATHS providers indicated they would order a PSA test every 12 months (69%) and believed that, ideally, the hypothetical patient's primary care provider should be responsible for his life-long prostate cancer surveillance (60%). Most providers reported feeling either "moderately" or "very" comfortable addressing topics such as prostate cancer recurrence (59%), erectile dysfunction (64%), urinary incontinence (63%), and emotional needs (61%) with prostate cancer survivors. These results varied somewhat by provider characteristics including female sex, years in practice, and the number of prostate cancer survivors seen in their practice. CONCLUSIONS: These data suggest that most primary care providers in Alaska are poised to assume the care of prostate cancer survivors locally. However, we also found that large minorities of providers do not feel confident in their ability to manage common issues in prostate cancer survivorship, implying that continued access to specialists with more expert knowledge would be beneficial.
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    Modeling deterministic effects in hematopoietic system caused by chronic exposure to ionizing radiation in large human cohorts.
    (Health Phys, 2010-09) Akushevich, Igor V; Veremeyeva, Galina A; Dimov, Georgy P; Ukraintseva, Svetlana V; Arbeev, Konstantin G; Akleyev, Alexander V; Yashin, Anatoly I
    A new model of the hematopoietic system for humans chronically exposed to ionizing radiation allows for quantitative description of the initial hematopoiesis inhibition and subsequent increase in the risks of late stochastic effects such as leukemia. This model describes the dynamics of the hematopoietic stem cell compartment as well as the dynamics of each of the three blood cell types (leukocytes, erythrocytes, and platelets). The model parameters are estimated from the results of other experiments. They include the steady-state numbers of hematopoietic stem cells and peripheral blood cell lines for an unexposed organism, amplification parameters for each blood cell line, parameters describing the proliferation and apoptosis, parameters of feedback functions regulating the steady-state numbers, and characteristics of radiosensitivity in respect to cell death and non-lethal cell damages. The dynamic model of hematopoiesis is applied to the data on a subcohort of the Techa River residents with hematological measurements (e.g., blood counts) performed in 1950-1956 (which totals to about 3,500 exposed individuals). Among well-described effects observed in these data are the slope values of the dose-effect curves describing the hematopoietic inhibition and the dose rate patterns of the fractions of cytopenic states (e.g., leukopenia, thrombocytopenia). The model has been further generalized by inclusion of the component describing the risk of late stochastic effects. The risks of the development of late effects (such as leukemia) in population groups with specific patterns of early reactions in hematopoiesis (such as leukopenia induced by ionizing radiation) are investigated using simulation studies and compared to data.
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    Racial/ethnic variations in substance-related disorders among adolescents in the United States.
    (Archives of general psychiatry, 2011-11) Wu, Li-Tzy; Woody, George E; Yang, Chongming; Pan, Jeng-Jong; Blazer, Dan G
    While young racial/ethnic groups are the fastest growing population in the United States, data about substance-related disorders among adolescents of various racial/ethnic backgrounds are lacking.To examine the magnitude of past-year DSM-IV substance-related disorders (alcohol, marijuana, cocaine, inhalants, hallucinogens, heroin, analgesic opioids, stimulants, sedatives, and tranquilizers) among adolescents of white, Hispanic, African American, Native American, Asian or Pacific Islander, and multiple race/ethnicity.The 2005 to 2008 National Survey on Drug Use and Health.Academic research.Noninstitutionalized household adolescents aged 12 to 17 years.Substance-related disorders were assessed by standardized survey questions administered using the audio computer-assisted self-interviewing method.Of 72 561 adolescents aged 12 to 17 years, 37.0% used alcohol or drugs in the past year; 7.9% met criteria for a substance-related disorder, with Native Americans having the highest prevalence of use (47.5%) and disorder (15.0%). Analgesic opioids were the second most commonly used illegal drugs, following marijuana, in all racial/ethnic groups; analgesic opioid use was comparatively prevalent among adolescents of Native American (9.7%) and multiple race/ethnicity (8.8%). Among 27 705 past-year alcohol or drug users, Native Americans (31.5%), adolescents of multiple race/ethnicity (25.2%), adolescents of white race/ethnicity (22.9%), and Hispanics (21.0%) had the highest rates of substance-related disorders. Adolescents used marijuana more frequently than alcohol or other drugs, and 25.9% of marijuana users met criteria for marijuana abuse or dependence. After controlling for adolescents' age, socioeconomic variables, population density of residence, self-rated health, and survey year, adjusted analyses of adolescent substance users indicated elevated odds of substance-related disorders among Native Americans, adolescents of multiple race/ethnicity, adolescents of white race/ethnicity, and Hispanics compared with African Americans; African Americans did not differ from Asians or Pacific Islanders.Substance use is widespread among adolescents of Native American, white, Hispanic, and multiple race/ethnicity. These groups also are disproportionately affected by substance-related disorders.
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    Survival differences among native-born and foreign-born older adults in the United States.
    (PLoS One, 2012) Dupre, Matthew E; Gu, Danan; Vaupel, James W
    BACKGROUND: Studies show that the U.S. foreign-born population has lower mortality than the native-born population before age 65. Until recently, the lack of data prohibited reliable comparisons of U.S. mortality by nativity at older ages. This study provides reliable estimates of U.S. foreign-born and native-born mortality at ages 65 and older at the end of the 20(th) century. Life expectancies of the U.S. foreign born are compared to other developed nations and the foreign-born contribution to total life expectancy (TLE) in the United States is assessed. METHODS: Newly available data from Medicare Part B records linked with Social Security Administration files are used to estimate period life tables for nearly all U.S. adults aged 65 and older in 1995. Age-specific survival differences and life expectancies are examined in 1995 by sex, race, and place of birth. RESULTS: Foreign-born men and women had lower mortality at almost every age from 65 to 100 compared to native-born men and women. Survival differences by nativity were substantially greater for blacks than whites. Foreign-born blacks had the longest life expectancy of all population groups (18.73 [95% confidence interval {CI}, 18.15-19.30] years at age 65 for men and 22.76 [95% CI, 22.28-23.23] years at age 65 for women). The foreign-born population increased TLE in the United States at older ages, and by international comparison, the U.S. foreign born were among the longest-lived persons in the world. CONCLUSION: Survival estimates based on reliable Medicare data confirm that foreign-born adults have longer life expectancy at older ages than native-born adults in the United States.