Biomedical subjects

Yungtai Lo

Publications and source records attributed to Yungtai Lo.

7 recordsLinked to original sources

PubMed2003

Gender and hospitalization patterns among HIV-infected drug users before and after the availability of highly active antiretroviral therapy.

We examined highly active antiretroviral therapy (HAART) era and pre-HAART era hospitalization rates among 604 HIV-infected drug users in a prospective study in Bronx, New York. Medical history and risk behaviors were elicited by semiannual interviews. Standardized medical record review abstracted discharge diagnoses for all hospitalizations. Hospitalization rates from January 1997 to December 2000 were compared with rates from January 1992 to December 1996. The rate of hospitalizations per 100 patient-years in the HAART era was 49.3 compared with 44.1 in the pre-HAART era (P = 0.13). Among women, the rate was significantly higher in the HAART era than in the pre-HAART era (68.1 vs. 49.4 hospitalizations per 100 patient-years, respectively; P = 0.01). In the second era, HAART users had lower rates than those who did not use HAART (37.2 vs. 83.4 hospitalizations per 100 patient-years, respectively; P < 0.001) for both HIV-associated and non-HIV-associated illnesses. Multivariate analysis revealed that in the HAART era, female gender (relative risk ratio = 1.72, P = 0.03) and not using HAART (relative risk ratio = 1.82, P = 0.02) independently predicted increased hospitalization risk. In the pre-HAART era, women were at independently higher risk of hospitalization (relative risk ratio = 1.36, P = 0.05). Among HIV-infected drug users, those who use HAART have a decreased risk of hospitalization; those who do not use HAART remain at high risk of continuing morbidity from both HIV-related and non-HIV-related illness and have high hospitalization rates.

AIDS-Related Opportunistic Infections↗

PubMed2003

The association of hepatitis C prevalence, activity, and genotype with HIV infection in a cohort of New York City drug users.

Factors associated with serum HCV antibody, HCV RNA level, and HCV genotype were assessed in 557 current and former drug users. Additional assays included HIV antibody, CD4+ lymphocyte counts, HIV viral loads, and hepatitis B markers. Seventy-five percent of subjects were anti-HCV positive, of whom 75% had detectable HCV RNA (median, 5.04 x 10(5) IU/mL; range, 1020-15.7 x 10(6)). On multivariate analysis HCV seropositivity was associated with history of drug injection, HIV seropositivity, and increased age and inversely with drug snorting. Among anti-HCV-positive persons, detectable HCV RNA was independently associated with HIV seropositivity, male gender, and history of injection and inversely associated with hepatitis B surface antigen positivity. Among persons with detectable HCV RNA, higher levels were independently associated with higher HIV viral load, increased age, and genotypes 2a and 2b. These findings demonstrate an association of HCV RNA level with HIV viral load, independent of the level of immunosuppression. However, a substantial degree of the person-to-person variability in the prevalence and level of detectable HCV RNA remains unexplained.

Adult↗

PubMed2003

Burden of asthma in inner-city elementary schoolchildren: do school-based health centers make a difference?

BACKGROUND: About 1400 school-based health centers (SBHCs) provide care to 1.1 million children. However, it is unknown if access to on-site services is associated with a better outcome. OBJECTIVE: To compare outcomes including hospitalizations, emergency department visits, and school absenteeism in elementary schoolchildren with asthma who were grouped according to their enrollment at schools that have or do not have SBHCs. SETTING: Six elementary schools in The Bronx, NY (4 schools with and 2 without SBHCs). PARTICIPANTS: Nine hundred forty-nine inner-city schoolchildren with asthma. DESIGN: To collect baseline data for a longitudinal study, we surveyed parents to identify children with asthma, and to obtain information about symptoms and the use of health services in the last 12 months. Participating schools provided absenteeism information. RESULTS: Of 6433 parents surveyed, 74% completed the questionnaires. The prevalence of asthma was 19.9% and the morbidity was high-during the previous year, 46.2% had been treated for asthma in an emergency department; 12.6% had been hospitalized. Emergency department use was not associated with SBHCs. However, in univariate and multivariate analyses, the rate of hospitalization was higher among children enrolled at schools without an SBHC (rate ratio, 1.5; 95% confidence interval, 1.1-1.9). In addition, schoolchildren with asthma enrolled in the schools without an SBHC missed more days of school than those enrolled in schools with an SBHC (mean [SD], 21.3 [15.4] vs 18.2 [13.0], respectively; P =.02). CONCLUSION: Access to SBHCs was associated with a reduction in the rate of hospitalization and a gain of 3 days of school for schoolchildren who have asthma.

Absenteeism↗

PubMed2002

A prospective study of adherence and viral load in a large multi-center cohort of HIV-infected women.

OBJECTIVES: To examine the relationship between antiretroviral adherence and viral load, and to determine the predictors of adherence over time in HIV-infected women. DESIGN: Prospective observational study. METHODS: One-hundred sixty-one HIV-infected women who were taking antiretroviral therapy for a median of 3.0 years were recruited from the HIV Epidemiology Research Study, a multicenter cohort study of HIV infection in women. Antiretroviral adherence (percent of doses taken as prescribed) was measured over a 6-month period using MEMS caps. At baseline and follow-up, CD4 lymphocyte count and viral load were measured, and a standardized interview was administered to elicit medication history and drug use behaviors. To examine changes in adherence over time, the mean adherence to all antiretroviral agents was calculated for each monitored month. RESULTS: Adherence varied significantly over time (P < 0.001), ranging from a mean of 64% in month 1 to 45% in month 6. Nearly one-fourth of the participants had a 10% or greater decrease in adherence between consecutive months. Virologic failure occurred in 17% of women with adherence of > or = 88%, 28% of those with 45-87% adherence, 43% of those with 13-44% adherence, and 71% of those with < or = 12% adherence. In multivariate analysis, factors predicting lower adherence included active drug use, alcohol use, more frequent antiretroviral dosing, shorter duration of antiretroviral use, younger age, and lower initial CD4 lymphocyte count. CONCLUSIONS: Antiretroviral adherence is not stable over time. Interventions aimed at monitoring and improving long-term adherence in women are urgently needed.

Adult↗

PubMed2002

Permutation tests for detecting and estimating mixtures in task performance within groups.

We propose a two-sample permutation test incorporating mixture models as a general tool for detecting and quantifying effects on task performance. We illustrate the proposed method with examples where the dependent measures under investigation are recorded for normal controls and relatives of patients with schizophrenia on a delayed response, spatial and object working memory task. Our mixture modelling in relatives allows the component distributions to arise from different continuous parametric families. We also investigate the effects of the within-family correlation and the prior distribution of the mixing proportion on the test results. The power of the test depends on sample sizes, the mixing proportion, the difference in component means and the ratio of component variances.

Humans↗

PubMed2002

Spatial and object working memory impairments in schizophrenia patients: a Bayesian item-response theory analysis.

This study reports evidence that schizophrenia patients are significantly impaired in both spatial and object (shape) working memory. A 3-s delay between exposure and recall of targets was used and Bayesian item-response theory was applied to compensate for the tasks' differential difficulty while simultaneously taking account of missing data from participant attrition. Weaker evidence was found that in schizophrenia both domains are equally impaired on average, that spatial and object working memory appear to be more highly correlated with each other in the schizophrenia population than in the normal population, and that schizophrenia patients show greater variability in spatial than object working memory performance.

Adult↗

PubMed2002

Predictors of hospitalization for HIV-positive women and men drug users, 1996-2000.

OBJECTIVE: This study sought to determine whether health outcomes differed by gender in a cohort of African American, Hispanic American, and white drug users. METHODS: The authors studied hospitalization rates and discharge diagnoses in the HERO Study, an ongoing prospective study of drug users that included HIV-positive and HIV-negative opiate users. The data are from 1996-2000, when highly active antiretroviral therapy (HAART) was available. RESULTS: Women had higher rates of hospitalization than men independent of HIV status, and there was no association between ethnicity and hospitalization. Being a woman was an independent risk factor for HIV and non-HIV-related hospitalization. CONCLUSION: Health disparities between men and women extend to HIV.

Adult↗