Biomedical subjects

Yanli Zhao

Publications and source records attributed to Yanli Zhao.

8 recordsLinked to original sources

PubMed2006

Psychosocial outcomes and drug attributes affecting treatment choice in men receiving sildenafil citrate and tadalafil for the treatment of erectile dysfunction: results of a multicenter, randomized, open-label, crossover study.

INTRODUCTION: Although sildenafil citrate (sildenafil) and tadalafil are efficacious and well-tolerated treatments for erectile dysfunction (ED), preference studies have shown that patients may favor one medication over the other. AIM: To determine whether psychosocial outcomes differed when men with ED received tadalafil compared with sildenafil. MAIN OUTCOME MEASURES: Measures included a treatment preference question, Psychological and Interpersonal Relationship Scales (PAIRS), and Drug Attribute Questionnaire. METHODS: Randomized, open-label, crossover study. After a 4-week baseline, men with ED (N = 367; mean age = 54 years; naïve to type 5 phosphodiesterase inhibitor therapy) were randomized: tadalafil for 12 weeks then sildenafil for 12 weeks or vice versa (8-week dose optimization/4-week assessment phases). During dose optimization, patients started with 10 mg tadalafil, or 25 or 50 mg sildenafil and could titrate to their optimal dose (10 or 20 mg tadalafil; 25, 50, or 100 mg sildenafil). Medications were taken as needed. Patients completing both 12-week periods chose which medication to continue during an 8-week extension. RESULTS: Of 291 men completing both treatment periods, 71% (N = 206) chose tadalafil and 29% (N = 85) chose sildenafil (P < 0.001) for the 8-week extension. When taking tadalafil compared with sildenafil men had higher mean endpoint scores on PAIRS Sexual Self-Confidence (tadalafil = 2.91 vs. sildenafil = 2.75; P < 0.001) and Spontaneity (tadalafil = 3.32 vs. sildenafil = 3.17; P < 0.001) Domains and a lower mean endpoint score on Time Concerns Domain (tadalafil = 2.2 vs. sildenafil = 2.59; P < 0.001). The two most frequently chosen drug attributes to explain treatment preference were ability to get an erection long after taking the medication and firmness of erections. Tadalafil and sildenafil were well tolerated with 12 (3.3%) patients discontinuing for an adverse event. CONCLUSIONS: As measured with PAIRS, men with ED had higher sexual self-confidence and spontaneity and less time concerns related to sexual encounters when treated with tadalafil compared with sildenafil. These psychosocial outcomes may help explain why more men (71%) preferred tadalafil for the treatment of ED in this clinical trial.

Adult↗

PubMed2006

Efficacy of tadalafil in men with erectile dysfunction naïve to phosphodiesterase 5 inhibitor therapy compared with prior responders to sildenafil citrate.

INTRODUCTION: Tadalafil, an inhibitor of phosphodiesterase 5 (PDE5), is indicated for treatment of erectile dysfunction. Most tadalafil clinical trials excluded patients with unsuccessful prior treatment with sildenafil citrate (sildenafil). AIM: This retrospective analysis of pooled data from 14 tadalafil clinical trials examines the effect of this exclusion by comparing efficacy results in 1,349 patients without prior sildenafil use (naïve, presumably a mixture of potential responders and nonresponders) with efficacy results in 1,440 patients previously responsive to sildenafil (prior responders). MAIN OUTCOME MEASURES: Efficacy measures included the International Index of Erectile Function (IIEF) erectile function (EF) domain, overall satisfaction (OS), and intercourse satisfaction (IS) domain scores; Sexual Encounter Profile (SEP) diary questions 2 through 5 (SEP2 [successful penetration], SEP3 [successful intercourse], SEP4 (satisfaction with hardness of erection), and SEP5 [overall satisfaction with the sexual experience]); and a Global Assessment Question (GAQ1) (13/14 trials) about erection improvement. Efficacy was compared using analysis of covariance (IIEF and SEP) and logistic regression (GAQ1) models. METHODS: After a 4-week, treatment-free, run-in period, patients in 14 double-blind, placebo-controlled, parallel-group trials were treated with tadalafil 10 mg, tadalafil 20 mg, or placebo for 12 weeks (dosed as needed before sexual activity, no more than once daily). RESULTS: Tadalafil improved erectile function compared with placebo (P < 0.001) in naïve patients and sildenafil prior responders for all efficacy measures. For most efficacy outcomes, responses in the naïve group (probable mix of responders and nonresponders) were not statistically different from responses in the prior-responder group (P >or= 0.10). CONCLUSIONS: The similar responses of these two patient groups observed in this post hoc analysis suggest, but do not confirm, that exclusion of sildenafil nonresponders in previously reported tadalafil clinical trials may not have substantially affected efficacy outcomes. Tadalafil improved erectile function in patients naïve to PDE5 inhibitor therapy and in patients who previously responded to sildenafil therapy.

3',5'-Cyclic-GMP Phosphodiesterases↗

PubMed2005

An open-label, multicentre, randomized, crossover study comparing sildenafil citrate and tadalafil for treating erectile dysfunction in men naïve to phosphodiesterase 5 inhibitor therapy.

OBJECTIVES: To compare treatment preference, efficacy, and tolerability of sildenafil citrate (sildenafil) and tadalafil for treating erectile dysfunction (ED) in men naïve to phosphodiesterase 5 (PDE5) inhibitor therapy. PATIENTS AND METHODS: This was an open-label, crossover study of sildenafil and tadalafil (taken as needed). After a 4-week baseline assessment, 367 men with ED (mean age 54 years) were randomized to receive sildenafil for 12 weeks followed by tadalafil for 12 weeks or vice versa (8-week dose optimization and 4-week assessment phases). During dose optimization, patients started taking 25- or 50-mg sildenafil or 10-mg tadalafil and could titrate to find their optimum dose (25-, 50- or 100-mg sildenafil; 10- or 20-mg tadalafil). After completing both 12-week periods, patients chose which treatment to continue during an 8-week extension. Efficacy was measured with the International Index of Erectile Function (IIEF) and Sexual Encounter Profile (SEP) diary. RESULTS: Of the 291 men who completed both treatments, 85 (29%) chose sildenafil and 206 (71%) chose tadalafil (P < 0.001) for the 8-week extension. The IIEF erectile function domain scores were 14.2 at baseline, 23.9 at endpoint on sildenafil, and 24.3 at endpoint on tadalafil (P = 0.08, sildenafil vs tadalafil). The mean per patient percentage success scores for SEP2 (penetration) were: baseline (46%), sildenafil (post-baseline 82%) and tadalafil (post-baseline 85%; P = 0.06, sildenafil vs tadalafil), and for SEP3 (successful intercourse) were: baseline (19%), sildenafil (post-baseline 72%), and tadalafil (post-baseline 77%; P = 0.003, sildenafil vs tadalafil). The only treatment-emergent adverse events that were reported by >5% of men were headache and flushing. CONCLUSIONS: In men with ED who were naïve to PDE5 inhibitor therapy, sildenafil and tadalafil were both effective and well tolerated. After treatment with sildenafil and tadalafil, 29% of men chose sildenafil and 71% chose tadalafil for ED therapy during an 8-week extension.

Adolescent↗

PubMed2005

Health-related quality of life, functional impairment, and healthcare utilization by veterans: veterans' quality of life study.

OBJECTIVES: To describe the health status of veterans receiving care in a veterans integrated service network (VISN). DESIGN: Cross-sectional survey with prospective follow-up. SETTING: Former Upper Midwest VISN 13 (now a part of VISN 23), a regional Veterans Affairs (VA) network comprising five inpatient facilities and associated outpatient clinics. PARTICIPANTS: All veterans in VISN 13 who had at least one inpatient or outpatient encounter between October 1, 1997, and March 31, 1998. MEASUREMENTS: Health-related quality of life (HRQOL) assessed using subscales and component summaries from the 36-item short form for veterans (SF36-V), functional status assessed according to limitations in activities of daily living (ADLs), healthcare utilization assessed according to outpatient visits and hospitalizations, and death. RESULTS: Of 70,334 eligible veterans, 40,508 responded and reported baseline HRQOL significantly lower than that of the general U.S. population for the physical (35.6, P<.001) and mental (46.4, P<.001) component summary scores (PCS and MCS, respectively) of the SF36-V. Many reported complete inability or some difficulty in completing ADLs such as getting in and out of a chair (35.1%) and walking (45.3%). More than 58% indicated some degree of difficulty with at least one of the ADLs. In multivariate analysis, PCS and MCS were significantly associated with subsequent use of inpatient and outpatient care and with mortality. CONCLUSION: The low quality of life and associated high rates of health services utilization in VA patients imply a need for innovative strategies to improve the HRQOL and functional status of this population.

Aged↗

PubMed2003

Modified nonparametric approaches to detecting differentially expressed genes in replicated microarray experiments.

MOTIVATION: An important goal in analyzing microarray data is to determine which genes are differentially expressed across two kinds of tissue samples or samples obtained under two experimental conditions. Various parametric tests, such as the two-sample t-test, have been used, but their possibly too strong parametric assumptions or large sample justifications may not hold in practice. As alternatives, a class of three nonparametric statistical methods, including the empirical Bayes method of Efron et al. (2001), the significance analysis of microarray (SAM) method of Tusher et al. (2001) and the mixture model method (MMM) of Pan et al. (2001), have been proposed. All the three methods depend on constructing a test statistic and a so-called null statistic such that the null statistic's distribution can be used to approximate the null distribution of the test statistic. However, relatively little effort has been directed toward assessment of the performance or the underlying assumptions of the methods in constructing such test and null statistics. RESULTS: We point out a problem of a current method to construct the test and null statistics, which may lead to largely inflated Type I errors (i.e. false positives). We also propose two modifications that overcome the problem. In the context of MMM, the improved performance of the modified methods is demonstrated using simulated data. In addition, our numerical results also provide evidence to support the utility and effectiveness of MMM.

Algorithms↗

PubMed2003

Evaluation of a worksheet to structure teaching and learning outpatient internal medicine.

The Worksheet for Ambulatory Medicine (WAM) is an educational tool designed to enhance teaching and learning outpatient internal medicine. It was developed to identify student learning needs, focus teaching, and structure educational and patient care activities in a clinic setting. The purpose of the study was to assess the feasibility and educational value of using the WAM with medical students and preceptors. Sixty-five third- and fourth-year medical students and 12 supervising faculty at two university-based general medicine outpatient clinics used the WAM during required internal medicine clerkships. Students and faculty completed written evaluations. Results are reported as percentages of respondents agreeing or disagreeing with a variety of statements, and mean rating scores for several questions designed to assess the feasibility and educational value of using the worksheet. Student response rate was 89%; 83% found the WAM easy to use; 65% found it too structured. Half said the worksheet helped diagnostic decision making and note writing, and two-thirds thought it promoted careful thinking about differential diagnosis and aided in identifying learning issues. Some 56% said using the WAM motivated outside reading. Most students found it helpful for identifying patient agendas and focusing case presentations (61% and 67, respectively). Only 36% said the WAM helped with time management. Most preceptors thought the WAM helped identify earning issues, focus case presentations and clarify student expectations. There was less agreement among preceptors that it allowed them to demonstrate clinical reasoning or provide students with more autonomy in decision making. Nearly half the preceptors did not find it helpful with time management. Both students and preceptors rated the overall value and usefulness of the WAM as good to very good, and a majority recommended that others use it. Using the Worksheet for Ambulatory Medicine was feasible and educationally valuable for many third- and fourth-year medical students and their preceptor in a required ambulatory internal medicine clerkship.

Ambulatory Care↗

PubMed2002

Prevalence and methodology of evaluation for latex allergy among allergists in the United States: results of a cross-sectional survey.

BACKGROUND: Natural rubber latex allergy is a potentially life-threatening, Type I, immediate allergic reaction. Despite great strides in identification of high-risk groups, methods for diagnosis remain limited in the United States. OBJECTIVE: The objective of this study was to estimate the prevalence of evaluation for latex allergy and methodologies used by allergists in the United States. METHODS: A cross-sectional survey of all US Fellows of the American Academy of Allergy, Asthma and Immunology was conducted. RESULTS: Of 1,239 questionnaires mailed, 519 (42%) were returned. Ninety-five percent of responding allergists reported evaluating patients for latex allergy. RAST and skin prick testing were the most commonly used tests. Sixty-two percent of respondents reported performing prick testing for latex allergy, with those in academic practices significantly more likely to do so. Whereas respondents practicing in the Northern United States were significantly more likely to evaluate for latex allergy than those in the Southern United States, no associations were found between practice location and prick testing for latex allergy. There was no association between practice type and evaluation for latex allergy. Only 6% of allergists reported ever witnessing a patient with anaphylaxis during latex allergy testing. CONCLUSIONS: Almost all responding allergists evaluated patients for latex allergy, with approximately two thirds utilizing prick testing.

Confidence Intervals↗

PubMed2002

Prevalence and methodology of patch testing by allergists in the United States: results of a cross-sectional survey.

BACKGROUND: Patch testing is considered the gold standard for the diagnosis of allergic contact dermatitis. Whereas previous surveys have evaluated the patch testing practices of dermatologists, little information is available on the use of patch testing by allergists. OBJECTIVE: The objective of this study was to examine the prevalence of patch testing and associated methodologies used by allergists in the United States. METHODS: A cross-sectional survey of all US Fellows of the American Academy of Allergy, Asthma and Immunology was conducted. RESULTS: Of 1,239 questionnaires mailed, 519 (42%) were returned. Fifty-three percent of allergists reported performing patch testing. The majority (89%) patch tested 5 or fewer patients per month. Allergists who evaluated for latex allergy were twice as likely to patch test than those who did not. The most common patch test reading schedule was at both 48 and 72 hours (48%). Thirty-three percent of respondents performed only a single patch test reading. The majority (72%) used TRUE Test. Only 4% patch tested for Type IV allergy to dust mites. CONCLUSION: Many more allergists patch test than initially hypothesized. The patch testing methodologies used by allergists are similar to those of dermatologists.

Allergens↗