Honghu H. Liu

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

Background: Highly active antiretroviral therapy (HAART) became standard for HIV in 1996. Studies at that time showed that most people infected with HIV had initiated HAART, but that members of minority groups and poor people had lower HAART use. It is not known whether high levels of HAART use have been sustained or whether socioeconomic and racial disparities have diminished over time. Objectives: To determine the proportion of patients who had received and were receiving HAART by January 1998, and to evaluate predictors of HAART receipt. Design and Participants: Prospective cohort study of a national probability sample of 2267 adults receiving HIV care who completed baseline, first follow‐up, and second follow‐up interviews from January 1996 to January 1998. Main outcome variables: Proportion currently using HAART at second follow‐up (August 1997 to January 1998), contrasted with the cumulative proportions using HAART at any time before January 1998 and before December 1996. Analyses: Bivariate and multiple logistic regression analysis of population characteristics predicting current use of HAART at the time of the second follow‐up interview. Results: The proportion of patients ever having received HAART increased from 37% in December 1996 to 71% by January 1998, but only 53% of people were receiving HAART at the time of the second follow‐up interview. Differences between sociodemographic groups in ever using HAART narrowed after 1996. In bivariate analysis, several groups remained significantly less likely to be using HAART at the time of the second follow‐up interview: blacks, male and female drug users, female heterosexuals, people with less education, those uninsured and insured by Medicaid, those in the Northeast, and those with CD4 counts of ≥500 cells/&mgr;l (all p < .05). Using multiple logistic regression analysis, low CD4 count (for CD4 <50 cells/&mgr;l: odds ratio [OR], 3.20; p < .001) remained a significant predictor of current HAART use at the time of the second follow‐up interview, but lack of insurance (OR, 0.71; p < .05) predicted not receiving HAART. Conclusions: The proportion of persons under HIV care in the United States who had ever received HAART increased to over 70% of the affected population by January 1998 and the disparities in use between groups narrowed but did not disappear. However, nearly half of those eligible for HAART according to the U.S. Department of Health and Human Services guidelines were not actually receiving it nearly 2 years after these medications were first introduced. Strategies to promote the initiation and continuation of HAART are needed for those without contraindications and those who can tolerate it.

Approaches and recommendations for estimating minimally important differences for health-related quality of life measures.

We describe currently available approaches for estimating the minimally important difference (MID) and their associated strengths and weaknesses. Specifically, we show that anchor-based methods should be the primary method of estimating the MID because of the limitations of distribution-based methods. In addition, we provide recommendations for estimating the MID in future research.

Repeated Measures Longitudinal Analyses of HIV Virologic Response as a Function of Percent Adherence, Dose Timing, Genotypic Sensitivity, and Other Factors

Background: Adherence to antiretroviral medications is critical to achieving HIV viral suppression. Studies have been limited to cross-sectional analyses using measures that reflect only the percentage of prescribed doses taken (percent adherence), however. The contribution of dose timing and other factors to achieving virologic suppression has received less scrutiny. Methods: In a longitudinal study, we collected detailed adherence information using multiple tools along with demographic, clinical, social-behavioral, and virologic measures. Subjects were followed for 48 weeks. Percent adherence, dose-timing, genotypic sensitivity, and virologic outcomes were collected every 4 weeks. Repeated measures mixed effects models (RMMEMs) were used to model the relation between virologic outcomes and adherence as well as genotypic sensitivity and others. Results: Of the 141 subjects, mean percent adherence was 73% with a downward trend. Viral load (VL) dropped significantly (P = 0.01) over time. RMMEMs revealed that higher genotypic sensitivity, higher percent adherence, lower baseline VL, longer inclusion in the study, earlier HIV stage, and smaller dose-timing error were significantly associated with lower VL. In multivariate modeling, a 0.50 increase in the genotypic sensitivity score, a 10% increase in adherence, and a decrease of 3 hours of dose-timing error were associated with a decrease in log10 HIV RNA at 48 weeks of 0.69, 0.54, and 0.48, respectively (P < 0.05 for each). Conclusions: Long-term viral suppression requires consistent and high percent adherence accompanied by optimal interdose intervals. Efforts to improve viral outcomes should address not only missed doses but excessive variation in dose timing and prevention of adherence decline over time. Preventing the development and transmission of resistant variants is also critically important.

Half Standard Deviation Estimate of the Minimally Important Difference in HRQOL Scores

In addition to statistical significance, it is important to evaluate the magnitude of differences in health-related quality of life over time. Interest in establishing the minimal difference that is clinically important or the minimally important difference has burgeoned over the last few years. This review summarizes some of the leading approaches to estimating the minimally important difference, offers caveats on the minimally important difference estimation based on existing literature and provides recommendations for future work. The authors recommend using multiple anchors to estimate the minimally important difference, using only anchors that correspond to minimal change in health-related quality of life, reporting information about the variation around the estimates, and providing bounded estimates to reflect the uncertainty.

Acculturation of Attitudes Toward End-of-life Care: A Cross-cultural Survey of Japanese Americans and Japanese

OBJECTIVE: Cross-cultural ethical conflicts are common. However, little is known about how and to what extent acculturation changes attitudes toward end-of-life care and advance care planning. We compared attitudes toward end-of-life care among Japanese Americans and Japanese in Japan.DESIGN: Self-administered questionnaire in English and Japanese.SETTING AND PARTICIPANTS: Community-based samples of Japanese Americans in Los Angeles and Japanese in Nagoya, Japan: 539 English-speaking Japanese Americans (EJA), 340 Japanese-speaking Japanese Americans (JJA), and 304 Japanese living in Japan (JJ).MEASUREMENTS AND MAIN RESULTS: Few subjects (6% to 11%) had discussed end-of-life issues with physicians, while many (EJA, 40%; JJA, 55%; JJ, 54%) desired to do so. Most preferred group surrogate decision making (EJA, 75%; JJA, 57%; JJ, 69%). After adjustment for demographics and health status, desire for informing the patient of a terminal prognosis using words increased significantly with acculturation (EJA, odds ratio [OR] 8.85; 95% confidence interval, [95% CI] 5.4 to 14.3; JJA, OR 2.8; 95% CI 1.8 to 4.4; JJ, OR 1.0). EJA had more-positive attitudes toward forgoing care, advance care planning, and autonomous decision making.CONCLUSION: Preference for disclosure, willingness to forgo care, and views of advance care planning shift toward western values as Japanese Americans acculturate. However, the desire for group decision making is preserved. Recognition of the variability and acculturation gradient of end-of-life attitudes among Japanese Americans may facilitate decision making and minimize conflicts. Group decision making should be an option for Japanese Americans.

Complementary and Alternative Medicine Use and Substitution for Conventional Therapy by HIV-infected Patients

Background: HIV‐infected patients commonly use complementary and alternative medicine (CAM), but it is not known how often CAM is used as a complement or as a substitute for conventional HIV therapy. Objectives: To evaluate the prevalence and factors associated with CAM use with potential for adverse effects and CAM substitution for conventional HIV medication. Design and Participants: Cross‐sectional survey of U.S. national probability sample of HIV‐infected patients (2,466 adults) in care from December 1996 to July 1997. Main Outcome Variables: Any CAM use, CAM use with potential for adverse effects, and use of CAM as a substitute for conventional HIV therapy. Substitution was defined as replacement of some or all conventional HIV medications with CAM. Results: Fifty‐three percent of patients had recently used at least one type of CAM. One quarter of patients used CAM with the potential for adverse effects, and one‐third had not discussed such use with their health care provider. Patients with a greater desire for medical information and involvement in medical decision making and with a negative attitude toward antiretrovirals were more likely to use CAM. Three percent of patients substituted CAM for conventional HIV therapy. They were more likely to desire involvement in medical decision‐making (odds ratio, 1.8; 95% confidence interval, 1.0‐3.2) and to have a negative attitude toward antiretrovirals (odds ratio, 7.8; 95% confidence interval, 3.0‐19.0). Conclusions: Physicians should openly ask HIV‐infected patients about CAM use to prevent adverse effects and to identify CAM substitution for conventional HIV therapy.

Item Response Theory Analyses of Physical Functioning Items in the Medical Outcomes Study

Background:Constructing and evaluating item pools that measure a single domain of health-related quality of life (HRQOL) is one of the fundamental objectives of the Patient Reported Outcome Measurement and Information System (PROMIS) project. The initial focus of PROMIS is on 5 HRQOL domains: physical function, fatigue, pain, emotional distress, and social/role participation. Analysis of related, available data can inform construction of these new banks. Objective:We sought to inform the building of the PROMIS physical function item bank by evaluating physical functioning items administered to participants in the Medical Outcomes Study. Research Design:Secondary analyses of physical functioning items administered at baseline (Fall, 1986) to 3223 individuals in the Medical Outcomes Study. Subjects:The mean age of participants was 54 years old; 15% had less than a high school education, 30% had a high school education, 27% had some but <4 years of college, and 28% had 4 or more years of college. Sixty-one percent were female; 80% were non-Hispanic white, 14% non-Hispanic black, 3% Hispanic, 1% Asian, and 2% other race/ethnicity. Measures:Fifteen physical functioning items were selected for analyses including the 10 SF-36 physical functioning items, an item assessing limitations in everyday physical activities because of health problems, an item measuring satisfaction with physical ability, and 3 mobility items. Results:Cronbach’s alpha was 0.94 for the 15-item scale and item-total correlations ranged from 0.51 (limited in bathing or dressing) to 0.80 (limited walking several blocks). A one-factor confirmatory categorical model fit the data well according to practical fit indices (comparative fit index = 0.95), but the Root Mean Square Error of Approximation was 0.12. Estimated factor loadings were all large (0.72 to 0.96) and statistically significant. We fit the graded response model with freely estimated and fixed slope estimates to compare 2-PL and 1-PL models. The difference between these 2 goodness of fit statistics for the 2 models was statistically significant: &khgr;2 (df = 14) = 772.9, P < 0.001. Slope estimates for some of the items in the 2-PL model varied from the 1-PL common slope to a noteworthy extent (eg, items 2, 5, 7, 8, and 9). Category threshold estimates generally were similar for the 2 models. Threshold estimates for the 2-PL model ranged from –2.90 (item 14: between no, never, and yes, occasionally in bed or in a chair most or all of the day because of health) to 1.55 (item 12: between very satisfied and completely satisfied with physical ability to do what you want to do). Information peaked at –1.0 theta (information = 33.60) for the 2-PL model. Information was only 7.43 at 0.8 theta (2-PL) and decreased with increasing theta. Conclusions:The 15 physical functioning items provide reasonably good fit to a unidimensional item response theory model that provides satisfactory coverage of the lower levels of physical functioning but does not provide very much information at higher levels of functioning.

A Prospective Study of Patient-Physician Communication About Resuscitation

OBJECTIVE: To evaluate prospectively seriously ill patients characteristics, perceptions, and preferences associated with discussing resuscitation (CPR) with their physicians.

Variation in the Readability of Items Within Surveys

The objective of this studywas to estimate the variation in the readability of survey items within 2 widely used health-related quality-of-life surveys: the National Eye Institute Visual Functioning Questionnaire–25 (VFQ-25) and the Short FormHealth Survey, version 2 (SF-36v2). Flesch-Kincaid and Flesch Reading Ease formulas were used to estimate readability. Individual survey item scores and descriptive statistics for each survey were calculated. Variation of individual item scores from the mean survey score was graphically depicted for each survey. The mean reading grade level and reading ease estimates for the VFQ-25 and SF-36v2 were 7.8 (fairly easy) and 6.4 (easy), respectively. Both surveys had notable variation in item readability; individual itemreadability scores ranged from 3.7 to 12.0 (very easy to difficult) for the VFQ-25 and 2.2 to 12.0 (very easy to difficult) for the SF-36v2. Because survey respondents may not comprehend items with readability scores that exceed their reading ability, estimating the readability of each survey item is an important component of evaluating survey readability. Standards for measuring the readability of surveys are needed.

Association between use of specific drugs and antiretroviral adherence: findings from MACH 14.

To determine the association between individual substances of abuse and antiretroviral adherence, analyses require a large sample assessed using electronic data monitoring (EDM). In this analysis, EDM data from 1,636 participants in 12 US adherence-focused studies were analyzed to determine the associations between recent use of various substances and adherence during the preceding 4xa0weeks. In bivariate analyses comparing adherence among patients who had used a specific substance to those who had not, adherence was significantly lower among those who had recently used cocaine, other stimulants or heroin but not among those who had used cannabis or alcohol. In multivariate analyses controlling for sociodemographics, amount of alcohol use and recent use of any alcohol, cocaine, other stimulants and heroin each was significantly negatively associated with adherence. The significant associations of cocaine, other stimulants, heroin, and alcohol use with adherence suggest that these are important substances to target with adherence-focused interventions.ResumenPara determinar la asociación entre las distintas sustancias de abuso y de la adherencia antirretroviral, el análisis requiere una gran muestra evaluada mediante el control electrónico de datos (EDM). En este análisis, los datos de EDM de 1,636 participantes en 12 estudios de investigación de EE.UU. centrado en la adhesión fueron analizados para determinar la asociación entre el uso reciente de varias sustancias y la adhesión durante las cuatro semanas anteriores. En el análisis bivariado comparando la adherencia entre los pacientes que habían consumido una sustancia específica para los que no, la adhesión fue significativamente menor entre aquellos que habían consumido recientemente cocaína, otros estimulantes o heroína, pero no entre aquellos que habían consumido cannabis o alcohol. En el análisis multivariante controlando por las características sociodemográficas, la cantidad de consumo de alcohol y el uso reciente de cualquier tipo de alcohol, cocaína, otros estimulantes y heroína, cada uno fue significativa y negativamente asociados con la adherencia. Las asociaciones de cocaína, otros estimulantes, la heroína y el consumo de alcohol con la adhesión sugieren que estas sustancias son importantes para apuntar con la adhesión centrado las intervenciones.