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Dive into the research topics where Stephen Crystal is active.

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Featured researches published by Stephen Crystal.


The American Journal of Medicine | 2000

Health-related quality of life in patients with human immunodeficiency virus infection in the United States: results from the HIV cost and services utilization study

Ron D. Hays; William E. Cunningham; Cathy D. Sherbourne; Ira B. Wilson; Albert W. Wu; Paul D. Cleary; Daniel F. McCaffrey; John A. Fleishman; Stephen Crystal; Rebecca L. Collins; Ferd Eggan; Martin F. Shapiro; Samuel A. Bozzette

PURPOSE To measure health-related quality of life among adult patients with human immunodeficiency virus (HIV) disease; to compare the health-related quality of life of adults with HIV with that of the general population and with patients with other chronic conditions; and to determine the associations of demographic variables and disease severity with health-related quality of life. SUBJECTS AND METHODS We studied 2,864 HIV-infected adults participating in the HIV Cost and Services Utilization Study, a probability sample of adults with HIV receiving health care in the contiguous United States (excluding military hospitals, prisons, or emergency rooms). A battery of 28 items covering eight domains of health (physical functioning, emotional well-being, role functioning, pain, general health perceptions, social functioning, energy, disability days) was administered. The eight domains were combined into physical and mental health summary scores. SF-36 physical functioning and emotional well-being scales were compared with the US general population and patients with other chronic diseases on a 0 to 100 scale. RESULTS Physical functioning was about the same for adults with asymptomatic HIV disease as for the US population [mean (+/- SD) of 92+/-16 versus 90+/-17) but was much worse for those with symptomatic HIV disease (76+/-28) or who met criteria for the acquired immunodeficiency syndrome (AIDS; 58+/-31). Patients with AIDS had worse physical functioning than those with other chronic diseases (epilepsy, gastroesophageal reflux disease, clinically localized prostate cancer, clinical depression, diabetes) for which comparable data were available. Emotional well-being was comparable among patients with various stages of HIV disease (asymptomatic, 62+/-9; symptomatic, 59+/-11; AIDS, 59+/-11), but was significantly worse than the general population and patients with other chronic diseases except depression. In multivariate analyses, HIV-related symptoms were strongly associated with physical and mental health, whereas race, sex, health insurance status, disease stage, and CD4 count were at most weakly associated with physical and mental health. CONCLUSIONS There is substantial morbidity associated with HIV disease in adults. The variability in health-related quality of life according to disease progression is relevant for health policy and allocation of resources, and merits the attention of clinicians who treat patients with HIV disease.


Health Services Research | 2002

Medical Expenditures during the Last Year of Life: Findings from the 1992–1996 Medicare Current Beneficiary Survey

Donald R. Hoover; Stephen Crystal; Rizie Kumar; Usha Sambamoorthi; Joel C. Cantor

OBJECTIVE To compare medical expenditures for the elderly (65 years old) over the last year of life with those for nonterminal years. DATA SOURCE From the 1992-1996 Medicare Current Beneficiary Survey (MCBS) data from about ten thousand elderly persons each year. STUDY DESIGN Medical expenditures for the last year of life and nonterminal years by source of payment and type of care were estimated using robust covariance linear model approaches applied to MCBS data. DATA COLLECTION The MCBS is a panel survey of a complex weighted multilevel random sample of Medicare beneficiaries. A structured questionnaire is administered at four-month intervals to collect all medical costs by payer and service. Medicare costs are validated by claims records. PRINCIPAL FINDINGS From 1992 to 1996, mean annual medical expenditures (1996 dollars) for persons aged 65 and older were


Health Affairs | 2009

Broadened Use Of Atypical Antipsychotics: Safety, Effectiveness, And Policy Challenges

Stephen Crystal; Mark Olfson; Cecilia Huang; Harold Alan Pincus; Tobias Gerhard

37,581 during the last year of life versus


Journal of the American Geriatrics Society | 2003

Diagnosis and Treatment of Depression in the Elderly Medicare Population: Predictors, Disparities, and Trends

Stephen Crystal; Usha Sambamoorthi; James Walkup; Ayse Akincigil

7,365 for nonterminal years. Mean total last-year-of-life expenditures did not differ greatly by age at death. However, non-Medicare last-year-of-life expenditures were higher and Medicare last-year-of-life expenditures were lower for those dying at older ages. Last-year-of-life expenses constituted 22 percent of all medical, 26 percent of Medicare, 18 percent of all non-Medicare expenditures, and 25 percent of Medicaid expenditures. CONCLUSIONS While health services delivered near the end of life will continue to consume large portions of medical dollars, the portion paid by non-Medicare sources will likely rise as the population ages. Policies promoting improved allocation of resources for end-of-life care may not affect non-Medicare expenditures, which disproportionately support chronic and custodial care.


JAMA Psychiatry | 2015

Premature Mortality Among Adults With Schizophrenia in the United States

Mark Olfson; Tobias Gerhard; Cecilia Huang; Stephen Crystal; T. Scott Stroup

Atypical antipsychotic medications are increasingly used for a wide range of clinical indications in diverse populations, including privately and publicly insured youth and elderly nursing home residents. These trends heighten policy challenges for payers, patients, and clinicians related to appropriate prescribing and management, patient safety, and clinical effectiveness. For clinicians and patients, balancing risks and benefits is challenging, given the paucity of effective alternative treatments. For health care systems, regulators, and policymakers, challenges include developing the evidence base on comparative risks and benefits; defining measures of treatment quality; and implementing policies that encourage evidence-based practices while avoiding unduly burdensome restrictions.


AIDS | 2009

HIV infection and the risk of diabetes mellitus.

Adeel A. Butt; Kathleen A. McGinnis; Maria C. Rodriguez-Barradas; Stephen Crystal; Michael S. Simberkoff; Matthew Bidwell Goetz; David A. Leaf; Amy C. Justice

Objectives: To develop nationally representative estimates of rates of diagnosis of depression; to determine rates and type of treatment received by those diagnosed with depression; and to ascertain socioeconomic differences and trends in treatment rates of depression, including the effect of supplemental insurance coverage, for elderly Medicare fee‐for‐service beneficiaries.


American Journal of Public Health | 2000

Violence victimization after HIV infection in a US probability sample of adult patients in primary care.

Sally Zierler; William E. Cunningham; R.M. Andersen; Martin F. Shapiro; Sam Bozzette; Terry T. Nakazono; Sally C. Morton; Stephen Crystal; Michael D. Stein; Barbara J. Turner; Patti St. Clair

IMPORTANCE Although adults with schizophrenia have a significantly increased risk of premature mortality, sample size limitations of previous research have hindered the identification of the underlying causes. OBJECTIVE To describe overall and cause-specific mortality rates and standardized mortality ratios (SMRs) for adults with schizophrenia compared with the US general population. DESIGN, SETTING, AND PARTICIPANTS We identified a national retrospective longitudinal cohort of patients with schizophrenia 20 to 64 years old in the Medicaid program (January 1, 2001, to December 31, 2007). The cohort included 1,138,853 individuals, 4,807,121 years of follow-up, and 74,003 deaths, of which 65,553 had a known cause. MAIN OUTCOMES AND MEASURES Mortality ratios for the schizophrenia cohort standardized to the general population with respect to age, sex, race/ethnicity, and geographic region were estimated for all-cause and cause-specific mortality. Mortality rates per 100,000 person-years and the mean years of potential life lost per death were also determined. Death record information was obtained from the National Death Index. RESULTS Adults with schizophrenia were more than 3.5 times (all-cause SMR, 3.7; 95% CI, 3.7-3.7) as likely to die in the follow-up period as were adults in the general population. Cardiovascular disease had the highest mortality rate (403.2 per 100,000 person-years) and an SMR of 3.6 (95% CI, 3.5-3.6). Among 6 selected cancers, lung cancer had the highest mortality rate (74.8 per 100,000 person-years) and an SMR of 2.4 (95% CI, 2.4-2.5). Particularly elevated SMRs were observed for chronic obstructive pulmonary disease (9.9; 95% CI, 9.6-10.2) and influenza and pneumonia (7.0; 95% CI, 6.7-7.4). Accidental deaths (119.7 per 100,000 person-years) accounted for more than twice as many deaths as suicide (52.0 per 100,000 person-years). Nonsuicidal substance-induced death, mostly from alcohol or other drugs, was also a leading cause of death (95.2 per 100,000 person-years). CONCLUSIONS AND RELEVANCE In a US national cohort of adults with schizophrenia, excess deaths from cardiovascular and respiratory diseases implicate modifiable cardiovascular risk factors, including especially tobacco use. Excess deaths directly attributable to alcohol or other drugs highlight threats posed by substance abuse. More aggressive identification and management of cardiovascular risk factors, as well as reducing tobacco use and substance abuse, should be leading priorities in the medical care of adults with schizophrenia.


Alcoholism: Clinical and Experimental Research | 2005

A temporal and dose-response association between alcohol consumption and medication adherence among veterans in care.

R. Scott Braithwaite; Kathleen A. McGinnis; Joseph Conigliaro; Stephen A. Maisto; Stephen Crystal; Nancy L. Day; Robert L. Cook; Adam J. Gordon; Michael W. Bridges; Jason F. S. Seiler; Amy C. Justice

Background:The influence of HIV infection on the risk of diabetes is unclear. We determined the association and predictors of prevalent diabetes mellitus in HIV infected and uninfected veterans. Methods:We determined baseline prevalence and risk factors for diabetes between HIV infected and uninfected veterans in the Veterans Aging Cohort Study. Logistic regression was used to determine the odds of diabetes in HIV infected and uninfected persons. Results:We studied 3227 HIV-infected and 3240 HIV-uninfected individuals. HIV-infected individuals were younger, more likely to be black males, have HCV coinfection and a lower BMI. HIV-infected individuals had a lower prevalence of diabetes at baseline (14.9 vs. 21.4%, P < 0.0001). After adjustment for known risk factors, HIV-infected individuals had a lower risk of diabetes (odds ratio = 0.84, 95% confidence interval = 0.72–0.97). Increasing age, male sex, minority race, and BMI were associated with an increased risk. The odds ratio for diabetes associated with increasing age, minority race and BMI were greater among HIV-infected veterans. HCV coinfection and nucleoside and nonnucleoside reverse transcriptase inhibitor therapy were associated with a higher risk of diabetes in HIV-infected veterans. Conclusion:Although HIV infection itself is not associated with increased risk of diabetes, increasing age; HCV coinfection and BMI have a more profound effect upon the risk of diabetes among HIV-infected persons. Further, long-term ARV treatment also increases risk. Future studies will need to determine whether incidence of diabetes mellitus differs by HIV status.


BMJ | 2012

Differential risk of death in older residents in nursing homes prescribed specific antipsychotic drugs: population based cohort study

Krista F. Huybrechts; Tobias Gerhard; Stephen Crystal; Mark Olfson; Jerry Avorn; Robert Marc Levin; Judith A. Lucas; Sebastian Schneeweiss

OBJECTIVES This study estimated the proportion of HIV-infected adults who have been assaulted by a partner or someone important to them since their HIV diagnosis and the extent to which they reported HIV-seropositive status as a cause of the violence. METHODS Study participants were from a nationally representative probability sample of 2864 HIV-infected adults who were receiving medical care and were enrolled in the HIV Costs and Service Utilization Study. All interviews (91% in person, 9% by telephone) were conducted with computer-assisted personal interviewing instruments. Interviews began in January 1996 and ended 15 months later. RESULTS Overall, 20.5% of the women, 11.5% of the men who reported having sex with men, and 7.5% of the heterosexual men reported physical harm since diagnosis, of whom nearly half reported HIV-seropositive status as a cause of violent episodes. CONCLUSIONS HIV-related care is an appropriate setting for routine assessment of violence. Programs to cross-train staff in antiviolence agencies and HIV care facilities need to be developed for men and women with HIV infection.


Journal of Acquired Immune Deficiency Syndromes | 2000

Prevalence and predictors of Highly active antiretroviral therapy use in patients with HIV infection in the United States

William E. Cunningham; Leona E. Markson; Ronald Andersen; Stephen Crystal; John A. Fleishman; Carol E. Golin; Allen L. Gifford; Honghu H. Liu; Terry T. Nakazono; Sally C. Morton; Samuel A. Bozzette; Martin F. Shapiro; Neil S. Wenger

BACKGROUND Previous studies have shown that alcohol consumption is associated with decreased medication adherence, but this association may be confounded by characteristics common among those who drink heavily and those who fail to adhere (e.g., illicit drug use). Our objective was to determine whether there are temporal and dose-response relationships between alcohol consumption and poor adherence. METHODS We administered telephone interview surveys to participants in the Veterans Aging Cohort Study, an eight-site observational study of HIV+ and matched HIV- veterans in care, to determine whether alcohol consumption on a particular day was associated with nonadherence to prescribed medications on that same day. We used the Time Line Follow Back to measure alcohol consumption and the Time Line Follow Back Modified for Adherence to measure adherence. Individuals were categorized as abstainers (no alcohol in past 30 days), nonbinge drinkers (alcohol in past 30 days but < or =four standard drinks on each day), or binge drinkers (> or =five standard drinks on at least one day). RESULTS Among 2702 respondents, 1582 (56.6%) were abstainers, 931 (34.5%) were nonbinge drinkers, and 239 (8.9%) were binge drinkers. Abstainers missed medication doses on 2.4% of surveyed days. Nonbinge drinkers missed doses on 3.5% of drinking days, 3.1% of postdrinking days, and 2.1% of nondrinking days (p < 0.001 for trend), and this trend was more pronounced among HIV+ individuals than HIV- individuals. Binge drinkers missed doses on 11.0% of drinking days, 7.0% of postdrinking days, and 4.1% of nondrinking days (p < 0.001 for trend), and this trend was comparably strong for HIV+ and HIV- individuals. CONCLUSIONS Among veterans in care, self-reported alcohol consumption demonstrates a temporal and dose-response relationship to poor adherence. HIV+ individuals may be particularly sensitive to alcohol consumption.

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