Biomedical subjects

Haiyi Xie

Publications and source records attributed to Haiyi Xie.

25 records · Page 2Linked to original sources

PubMed2004

Response to vocational rehabilitation during treatment with first- or second-generation antipsychotics.

OBJECTIVE: Second-generation antipsychotics may enhance the rehabilitation of individuals with schizophrenia. The authors hypothesized that clients receiving second-generation antipsychotics would use vocational rehabilitation services more effectively and would have better employment outcomes than those receiving first-generation antipsychotics. METHODS: Ninety unemployed clients with schizophrenia and related disorders who were beginning a vocational rehabilitation program were followed for nine months. Three groups were defined according to the medication in use at study entry: olanzapine (N=39), risperidone (N=27), or first-generation antipsychotics only (N=24). Participants were interviewed monthly. RESULTS: The olanzapine and risperidone groups did not differ on any employment outcomes. On most vocational indicators, clients receiving second-generation agents did not differ from those receiving first-generation agents. However, at nine months the second-generation group had a significantly higher rate of participation in vocational training; a trend was found toward a higher rate of paid employment. All groups showed substantial improvement in employment outcomes after entering a vocational program. CONCLUSIONS: The hypothesis that second-generation antipsychotics promote better employment outcomes than first-generation antipsychotics was not upheld. However, second-generation agents appear to be associated with increased participation in vocational rehabilitation.

Adult↗

PubMed2004

Benzodiazepine prescription practices and substance abuse in persons with severe mental illness.

BACKGROUND: Benzodiazepines have many benefits for persons with severe mental disorders, but they may also lead to or exacerbate substance abuse. An American Psychiatric Association taskforce established practice guidelines in 1990 to assist physicians in managing these and other potential side effects of benzodiazepine use. The objectives of this study were to determine the prevalence of benzodiazepine use among persons with psychiatric disorders and to evaluate compliance with published prescribing guidelines. METHOD: We studied benzodiazepine use among New Hampshire Medicaid beneficiaries aged 18 to 64 years with ICD-9 diagnoses that were grouped under the headings "schizophrenia," "bipolar disorder," "major depression," and "other psychiatric disorders" from Jan. 1995 through Dec. 1999. Rates and length of use, frequency of high-potency/fast-acting prescriptions, and diazepam-equivalent dosages were compared for those with and without retrospectively determined evidence of substance abuse, substance dependence, or a procedure code indicating treatment for a substance use disorder (SUD). RESULTS: Five-year prevalence of benzodiazepine use for persons with and without SUD was 63% versus 54% for schizophrenia, 75% versus 58% for bipolar disorder, 66% versus 49% for major depression, and 48% versus 40% for other psychiatric disorders. Differences were statistically significant over 5 years and in 1999 (p <.0001). Among persons with major depression or other psychiatric disorders, those with comorbid SUD were more likely to use fast-acting/high-potency benzodiazepines; there were no such differences for those with schizophrenia or bipolar disorder. Persons with bipolar disorder or other psychiatric disorders and SUD received significantly higher diazepam-equivalent dosages than did those without SUD. CONCLUSION: Contrary to published guidelines, rates of benzodiazepine use are higher among Medicaid beneficiaries with severe mental illness and co-occurring SUD than among persons with severe mental illness alone. Additional research and possibly a reassessment of prescribing guidelines are recommended.

Adolescent↗

PubMed2003

Using discrete-time survival analysis to examine patterns of remission from substance use disorder among persons with severe mental illness.

Investigators in mental health research are often interested in examining critical events such as onset, relapse, and recovery from illness, including substance use disorders. As data on these critical events are often collected at discrete-time intervals (e.g., weekly, monthly, or yearly), discrete-time survival models are more appropriate than well-known continuous-time methods. In this paper, we present discrete-time survival analysis methods at an introductory level. Using data collected every 6 months from a 3-year study of assertive community treatment in New Hampshire, we show that discrete-time survival models can be used to analyze patterns of remission from substance use disorder among clients with severe mental illness. The main questions investigated are (1) when are remissions more likely to occur? and (2) what variables predict remission? The results indicate that remission is more likely to occur in the first 6 months and in the 3rd year of the study. Gender, age, baseline use of substances, and diagnosis are strong predictors of remission.

Case Management↗

PubMed2003

Benzodiazepine use and abuse among patients with severe mental illness and co-occurring substance use disorders.

OBJECTIVES: Because use of benzodiazepines may exacerbate existing substance use disorders or become abused substances, prescription of benzodiazepines for patients with severe mental illness (schizophrenia or bipolar disorder) and co-occurring substance use disorders (abuse or dependence) is controversial. The authors examined benzodiazepine use and associated psychiatric, substance abuse, and institutional outcomes in a six-year longitudinal study of patients with co-occurring disorders. METHODS: At baseline and yearly follow-up for six years, 203 patients with co-occurring severe mental illness and substance use disorder were prospectively assessed for medication use, substance use, psychiatric symptoms, use of hospitalization, and quality of life. RESULTS: Almost one-half of the patients (43 percent) reported taking prescribed benzodiazepines at the time of at least one assessment. Patients taking prescribed benzodiazepines were more likely to have high scores on measures of overall symptoms and affective symptoms (anxiety and depression) and low ratings for general quality of life throughout the study. Benzodiazepine use was unrelated to remission of substance use disorder or hospitalization, but a greater proportion of patients who were prescribed benzodiazepines developed benzodiazepine abuse, compared with those who were not prescribed benzodiazepines (15 percent compared with 6 percent). CONCLUSIONS: Prescription benzodiazepine use was common among patients with co-occurring severe mental illness and a substance use disorder and was not associated with any of the measured outcomes other than increasing the likelihood of benzodiazepine abuse. Physicians should consider other treatments for anxiety in this population.

Adult↗

PubMed2003

Electron paramagnetic resonance assessment of brain tissue oxygen tension in anesthetized rats.

UNLABELLED: The adequacy of cerebral tissue oxygenation (PtO(2)) is a central therapeutic end point in critically ill and anesthetized patients. Clinically, PtO(2) is currently measured indirectly, based on measurements of cerebrovascular oxygenation using near infrared spectroscopy and experimentally, using positron emission tomographic scanning. Recent developments in electron paramagnetic resonance (EPR) oximetry facilitate accurate, sensitive, and repeated measurements of PtO(2). EPR is similar to nuclear magnetic resonance but detects paramagnetic species. Because these species are not abundant in brain (or other tissues) in vivo, oxygen-responsive paramagnetic lithium phthalocyanine crystals implanted into the cerebral cortex are used for the measurement of oxygen. The line widths of the EPR spectra of these materials are linear functions of PtO(2). We used EPR oximetry in anesthetized rats to study the patterns of PtO(2) during exposure to various inhaled and injected general anesthetics and to varying levels of inspired oxygen. Rats anesthetized with 2.0 minimum alveolar anesthetic concentration isoflurane maintained the largest PtO(2) (38.0 +/- 4.5 mm Hg) and rats anesthetized with ketamine/xylazine had the smallest PtO(2) (3.5 +/- 0.3 mm Hg) at a fraction of inspired oxygen (FIO(2)) of 0.21, P < 0.05. The maximal PtO(2) achieved under ketamine/xylazine anesthesia with FIO(2) of 1.0 was 8.8 +/- 0.3 mm Hg, whereas PtO(2) measured during isoflurane anesthesia with FIO(2) of 1.0 was 56.3 +/- 1.7 mm Hg (P < 0.05). These data highlight the experimental utility of EPR in measuring PtO(2) during anesthesia and serve as a foundation for further study of PtO(2) in response to physiologic perturbations and therapeutic interventions directed at preventing cerebral ischemia. IMPLICATIONS: Using in vivo electron paramagnetic resonance oximetry, we studied the patterns of cerebral tissue oxygenation (PtO(2)) during exposure to various inhaled and injected general anesthetics, and to varying levels of inspired oxygen. These data show that inhaled anesthetics result in larger levels of PtO(2) in the brain than do several injectable anesthetics. The results highlight the experimental utility of electron paramagnetic resonance in measuring PtO(2) during anesthesia and serve as a foundation for further study of PtO(2) in response to physiologic perturbations and therapeutic interventions directed at preventing cerebral ischemia.

Anesthesia↗

PubMed2001

Substitution between Formal and Informal Care for Persons with Severe Mental Illness and Substance Use Disorders.

BACKGROUND: Persons with severe mental illness (SMI) often get extensive informal care from family members and friends as well as substantial amounts of formal treatment from paid professionals. Both sources of care are well documented, but very little is known about how one affects the other. AIMS OF THE STUDY: This analysis estimates the extent of substitution between direct care provided by family and friends and formal treatment for people with severe mental illness and substance use disorders. Separate estimates are generated for short-term and long-term effects. METHODS: Data are from a randomized clinical trial conducted at seven mental health centers in New Hampshire between 1989 and 1995. The study includes detailed data for 193 persons with dual disorders measured at study entry and every six months for three years. Hours of informal care were compared with total treatment costs within each six-month period to measure short-term effects. Average amount of informal care over three years represented long-term caregiving practices. Measures of informal care are from interviews with informal caregivers. Treatment costs are based on combined data from management information systems, Medicaid claims, hospital records, and self reports. We used mixed effects repeated measures regression to estimate longitudinal effects and a multiple imputation technique to test the sensitivity of results to missing data. RESULTS: In the short-term, persons with bipolar disorder used significantly more formal care as informal care increased (complementarity). The relationship between short-term informal and formal care was significantly weaker for persons with schizophrenia. For both diagnostic groups there was a long-term substitution effect; a 4-6% increase in informal care hours was associated with an approximate 1% decrease in formal care costs. DISCUSSION: Although they must be confirmed by further research, these findings suggest that there is a significant and strong relationship between care given by family and friends and that supplied by formal treatment providers. The analysis indicates that the short-term relationship between informal care and formal treatment tends to be complementary, but differs according to diagnosis. Long-term effects, which are possibly related to changing role perceptions, show substitution between the two forms of care. Missing data for family care hours in some time periods was a concern in this study. However, the consistency in results between the analyses that used imputed data and the model using only original data increase our confidence in the findings. Although there may be some endogeneity between formal and informal care in other treatment settings we believe the unique characteristics of the service-rich environment in which this study was conducted limit that concern here. IMPLICATIONS FOR HEALTH CARE PROVISION AND USE: The amount of care provided by informal caregivers has a significant impact on formal treatment costs. Models of care that explicitly acknowledge the interplay between the two types of care are needed to ensure efficient combinations of formal and informal care. IMPLICATIONS FOR HEALTH POLICY FORMULATION: How to best to encourage informal support, without overburdening caregivers, is a key challenge facing policy makers and providers of mental health services. The merits of various approaches to reducing caregiver burden is a subject that needs more attention from researchers. In the interim, the demands on informal caregivers may mount as efforts to reduce health care spending continue. IMPLICATIONS FOR FURTHER RESEARCH: Informal care is not often included in economic evaluations of mental health treatment. Although additional research is needed to understand better the mechanisms by which informal care and formal treatment are related, we believe our results offer a strong argument for including measures of informal care in future economic evaluations.

Journal Article↗

PubMed1998

The economic benefits of supported employment for persons with mental illness.

BACKGROUND: Policies and programs that emphasize employment for persons with mental illness are often promoted with the goals of improving economic self-sufficiency and reducing dependence on public welfare programs. At present, there is little empirical evidence about the actual effect of vocational interventions on economic self-sufficiency or on use of public benefits by persons with mental illness. STUDY AIMS: This study provides a preliminary look at how participating in supported employment, a form of vocational rehabilitation emphasizing ongoing support in competitive jobs, affects the amount that participants earn from work and the total amount of income they receive from all sources. Further, we examine the extent to which receiving public benefits affects the amount earned from private employment, taking into consideration other factors that might be associated with benefit status. METHODS: Data are from a randomized trial of supported employment interventions. This analysis followed 137 of those study participants with severe mental illness for 18 months after they enrolled in either of two supported employment programs. Income from various sources was estimated based on interviews with study participants upon study entry and at six-month intervals thereafter. Changes in income from work, government and other sources were analyzed using paired Wilcoxon matched-pairs signed-ranks tests and t-tests. Using ordinary least-squares regression, we analyzed the effect of benefit status on changes in earnings, taking into account diagnosis, work history, education, program type, site of program, psychiatric symptoms, global functioning and previous earnings. RESULTS: Estimated total income increased by an average of $134 (US) per month after enrolling in supported employment. More than three-quarters of this increase was from government sources, such as Social Security and educational grants. The increase in government income was largely due to participants applying for and getting cash benefits for the first time. Social Security payments for those receiving benefits before enrollment did not change significantly. A small group of persons (n = 22) who did not receive Social Security benefits before or after enrolment earned significantly more from competitive employment after enrolling than did those who received benefits. This finding persisted after taking into acount differences in work history, clinical and functional variables and education. LIMITATIONS: Because of the relatively small sample size and the lack of continuous measures of income these results should be considered preliminary. CONCLUSIONS: Supported employment, one of the more effective forms of vocational rehabilitation for persons with mental illness, did not reduce dependence on government support. Receiving government benefits was associated with lower earnings from work. IMPLICATIONS FOR HEALTH CARE PROVISION AND USE: These findings suggest that most persons in treatment for severe mental illness need continued public financial support even after enrolling in vocational rehabilitation programs. IMPLICATIONS FOR HEALTH POLICY FORMULATION: Undoubtedly increased labor force participation can benefit persons with mental illness in a number of ways. However, policy makers should be careful about justifying increased access to vocational programs on the basis of reduced spending for income support. Further, targeting such programs only to persons receiving income support may overlook the clients who can benefit most: those who are not currently receiving benefits. IMPLICATIONS FOR FURTHER RESEARCH: Policy makers need a better understanding of how vocational interventions and income support programs affect the income and well-being of persons with mental illness. Studies similar to this one should be repeated with larger, more diverse samples that will allow use of instrumental variables statistical techniques.

Journal Article↗