Biomedical subjects

David J Dorer

Publications and source records attributed to David J Dorer.

23 records · Page 2Linked to original sources

PubMed2003

Late aortic and graft-related events after thoracoabdominal aneurysm repair.

PURPOSE: Unlike abdominal aortic aneurysm repair, little information exists regarding aortic-related morbidity (synchronous/metachronous aneurysm or graft-related complications) after thoracoabdominal aneurysm (TAA) repair. This study was performed to define such events and identify factors related to their development. METHODS: Over a 15-year interval, 333 patients underwent TAA repair (type I, n = 90; 27%; type II, n = 59; 18%; type III, n = 118; 35%; and type IV, n = 66; 20%). Late aortic events were defined as aortic disease causing death or necessitating further intervention or graft-related complications (infection, pseudoaneurysm, branch occlusion) after hospital discharge. Variables were assessed for their association with aortic events with Cox proportional hazards regression. RESULTS: In-hospital mortality occurred in 28 patients (8.4%), which left 305 available for follow-up (mean length of follow-up, 26 months; interquartile range, 2.7 to 38.4 months). After TAA repair, aneurysm remained in 60 patients (19.7%; ascending/arch, n = 41; 68.3%; discontinuous infrarenal, n = 12; 20%; contiguous descending, n = 7; 11.7%; contiguous abdominal, n = 4; 6.7%). Events occurred in 33 individuals (10.8%) at 30 +/- 27 months after surgery. Twenty-four patients (73% of events; 7.9% of cohort) had aortic-related events, including another elective aneurysm repair (n = 16), urgent/emergent aneurysm operation (n = 5), acute dissection (n = 2), and atherothrombotic embolization (n = 1). Nine patients (27% of events; 2.9% of cohort) had graft-related incidents, including renovisceral occlusion (n = 5), visceral patch pseudoaneurysm (n = 2), graft infection (n = 2), and graft-esophageal fistula (n = 1). Variables independently predictive of events were female gender (odds ratio [OR], 2.3; P =.03), initial aneurysm rupture (OR, 4.8; P =.04), partial disease resection (OR, 4.2; P =.0008), and expansion of remaining aortic segments on imaging surveillance (OR, 2.5; P =.03). The event-free survival rates were 96% (95% CI, 93% to 98%) and 71% (95% CI, 60% to 83%) at 1 and 5 years. CONCLUSION: Late aortic events occur in at least 10% of patients after TAA repair and are usually the result of native aortic disease in remote (or noncontiguous) aortic segments. Graft-related complications, in particular, degeneration of inclusion anastamoses, are rare. Female gender, original presentation with rupture, and unresected disease identify those at highest risk. These findings verify the anatomic durability of TAA repair and suggest indefinite aortic surveillance is indicated for those at risk of events.

Aged↗

PubMed2002

Longitudinal comparison of anorexia nervosa subtypes.

OBJECTIVE: To compare patients with restricting anorexia nervosa (ANR) and binge/purge anorexia nervosa (ANBP) on measures of impulsivity, course, and outcome. METHODS: One hundred thirty-six treatment-seeking women with AN followed prospectively for 8-12 years were reclassified at intake as 51 ANRs and 85 ANBPs according to the DSM-IV subtyping classification. Lifetime Axis I and Axis II disorders were assessed using structured interviews; follow-up interviews were conducted at 6-12-month intervals to collect weekly data on eating disorder symptomatology. RESULTS: Women with ANR and ANBP did not differ on history of substance abuse, kleptomania, suicidality, or borderline personality diagnosis at intake, or on rates of recovery, relapse, or mortality. By 8 years of follow-up, 62% of women with ANR crossed over to ANBP prospectively and only 12% of women with AN never reported regular binge/purge behaviors. CONCLUSIONS: The findings on impulsivity, course, and outcome do not support the current subtyping system. The high crossover rate in our sample from ANR to ANBP suggests that ANR represents a phase in the course of AN rather than a distinct subtype.

Anorexia Nervosa↗

PubMed2002

Predictors of treatment utilization among women with anorexia and bulimia nervosa.

OBJECTIVE: The authors sought predictors of treatment utilization among women with eating disorders. METHOD: Women diagnosed with either anorexia or bulimia nervosa (N=246) completed prospective evaluations of eating disorder status, comorbid disorders, global assessment of functioning, and treatment utilization. RESULTS: Women with anorexia nervosa received significantly more inpatient treatment than did women with bulimia nervosa. Predictors of treatment utilization included lower global assessment of functioning scores and presence of personality disorders. CONCLUSIONS: Women with more severe pathology have higher treatment utilization rates. This pattern may explain the seeming lack of treatment efficacy for eating disorders outside of randomized controlled studies.

Adolescent↗

PubMedDate not supplied

The problem of the placebo response in clinical trials for psychiatric disorders: culprits, possible remedies, and a novel study design approach.

The placebo response is a major issue in clinical trials for psychiatric disorders. Possible contributing factors to this problem include diagnostic misclassification, issues concerning inclusion/exclusion criteria, outcome measures' lack of sensitivity to change, measurement errors, poor quality of data entry and verification, waxing and waning of the natural course of illness, regression toward the mean phenomenon, patient and clinician expectations about the trial, study design issues, non-specific therapeutic effects, and high attrition. Over the past few decades, researchers have attempted to reduce the placebo effect in a variety of ways. Unfortunately, approaches with very little or no benefit have included restricting enrollment to selected populations, rater training, requirement of same rater, and placebo lead-in phases. Some benefits, although often marginal, have been derived from standardizing diagnostic procedures, managing clinicians' overestimation of change, simplification of study visits and assessments, minimizing non-specific, therapeutic effects, extending trial duration, reducing number of sites, increasing the sensitivity of outcome measures, and reducing the number of treatment arms. Thus far, there has been no attempt to develop new study designs aimed at reducing the placebo effect. We are proposing a novel study design, called 'Sequential Parallel Comparison Design', suitable for double-blind, placebo-controlled trials in psychiatric disorders. This design is aimed at reducing both the overall placebo response rate and the sample size required for such trials. Its usefulness in clinical research needs to be tested empirically. If this study design were to be found to meet its stated goals, this could markedly facilitate the process of clinical development of new compounds for the treatment of psychiatric disorders.

Clinical Trials as Topic↗

PubMedDate not supplied

The relationship between human semen characteristics and sperm apoptosis: a pilot study.

This work was undertaken to explore the association between human semen characteristics and apoptosis in ejaculated sperm. We collected semen samples from 23 consecutive male patients who presented to the Andrology Laboratory at Massachusetts General Hospital (MGH) for routine semen analysis. Sperm concentration and motility were measured using computer-assisted sperm analysis. Morphology was assessed using Tygerberg strict criteria. The DNA diffusion assay was used to assess the percentage of apoptosis in ejaculated sperm. In this assay, cells were mixed with agarose and placed into a microgel on a microscopic slide. The cells were stained with YOYO-1 dye, and apoptotic cells were viewed under a fluorescent microscope. Among 23 men, the mean (SD) sperm concentration, percent motility, percent progressive motility, and normal morphology were 125.5 (92.3) million/mL, 45.6% (22.2), 28.4% (15.2), and 8.0 (4.6), respectively. The mean (SD) percent of apoptosis in ejaculated sperm was 8.3% (6.2) with a range from 1.1% to 20.1%. There were inverse associations between percent apoptosis and sperm motility (P = .0025), progressive motility (P = .0051), and morphology with a normal or good pattern of fertilization by Kruger strict criteria (P = .0045), and a positive relationship between percent apoptosis and sperm tail defects (P = .0053). In ejaculated semen, the percent sperm apoptosis was associated with several measures of semen quality.

Adult↗