Biomedical subjects

B W Gillespie

Publications and source records attributed to B W Gillespie.

At least 19 recordsLinked to original sources

PubMed2006

Longer treatment time and slower ultrafiltration in hemodialysis: associations with reduced mortality in the DOPPS.

Longer treatment time (TT) and slower ultrafiltration rate (UFR) are considered advantageous for hemodialysis (HD) patients. The study included 22,000 HD patients from seven countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS). Logistic regression was used to study predictors of TT > 240 min and UFR > 10 ml/h/kg bodyweight. Cox regression was used for survival analyses. Statistical adjustments were made for patient demographics, comorbidities, dose of dialysis (Kt/V), and body size. Europe and Japan had significantly longer (P < 0.0001) average TT than the US (232 and 244 min vs 211 in DOPPS I; 235 and 240 min vs 221 in DOPPS II). Kt/V increased concomitantly with TT in all three regions with the largest absolute difference observed in Japan. TT > 240 min was independently associated with significantly lower relative risk (RR) of mortality (RR = 0.81; P = 0.0005). Every 30 min longer on HD was associated with a 7% lower RR of mortality (RR = 0.93; P < 0.0001). The RR reduction with longer TT was greatest in Japan. A synergistic interaction occurred between Kt/V and TT (P = 0.007) toward mortality reduction. UFR > 10 ml/h/kg was associated with higher odds of intradialytic hypotension (odds ratio = 1.30; P = 0.045) and a higher risk of mortality (RR = 1.09; P = 0.02). Longer TT and higher Kt/V were independently as well as synergistically associated with lower mortality. Rapid UFR during HD was also associated with higher mortality risk. These results warrant a randomized clinical trial of longer dialysis sessions in thrice-weekly HD.

Adult↗

PubMed2006

Mortality risk for patients receiving hemodiafiltration versus hemodialysis: European results from the DOPPS.

Hemodiafiltration (HDF) is used sporadically for renal replacement therapy in Europe but not in the US. Characteristics and outcomes were compared for patients receiving HDF versus hemodialysis (HD) in five European countries in the Dialysis Outcomes and Practice Patterns Study. The study followed 2165 patients from 1998 to 2001, stratified into four groups: low- and high-flux HD, and low- and high-efficiency HDF. Patient characteristics including age, sex, 14 comorbid conditions, and time on dialysis were compared between each group using multivariate logistic regression. Cox proportional hazards regression assessed adjusted differences in mortality risk. Prevalence of HDF ranged from 1.8% in Spain to 20.1% in Italy. Compared to low-flux HD, patients receiving low-efficiency HDF had significantly longer average duration of end-stage renal disease (7.0 versus 4.7 years), more history of cancer (15.4 versus 8.7%), and lower phosphorus (5.3 versus 5.6 mg/dl); patients receiving high-efficiency HDF had significantly more lung disease (15.5 versus 10.2%) and received a higher single-pool Kt/V (1.44 versus 1.35). High-efficiency HDF patients had lower crude mortality rates than low-flux HD patients. After adjustment, high-efficiency HDF patients had a significant 35% lower mortality risk than those receiving low-flux HD (relative risk=0.65, P=0.01). These observational results suggest that HDF may improve patient survival independently of its higher dialysis dose. Owing to possible selection bias, the potential benefits of HDF must be tested by controlled clinical trials before recommendations can be made for clinical practice.

Europe↗

PubMed2005

Estimating the impact of renal replacement therapy choice on outcome in severe acute renal failure.

BACKGROUND: Mortality in severe acute renal failure (ARF) requiring renal replacement therapy (RRT) approximates 50% and varies with clinical severity. Continuous RRT (CRRT) has theoretical advantages over intermittent hemodialysis (IHD) for critical patients, but a survival advantage with CRRT is yet to be clearly demonstrated. To date, no prospective controlled trial has sufficiently answered this question, and the present prospective outcome study attempts to compare survival with CRRT versus that with IHD. METHODS: Multivariable Cox-proportional hazards regression was used to analyze the impact of RRT modality choice (CRRT vs. IHD) on in-hospital and 100-day mortality among ARF patients receiving RRT during 2000 and 2001 at University of Michigan, using an "intent-to-treat" analysis adjusted for multiple comorbidity and severity factors. RESULTS: Overall in-hospital mortality before adjustment was 52%. Triage to CRRT (vs IHD) was associated with higher severity and unadjusted relative rate (RR) of in-hospital death (RR = 1.62, p = 0.001, n = 383). Adjustment for comorbidity and severity of illness reduced the RR of death for patients triaged to CRRT and suggested a possible survival advantage (RR = 0.81, p = 0.32). Analysis restricted to patients in intensive care for more than five days who received at least 48 hours of total RRT, showed the RR of in-hospital mortality with CRRT to be nearly 45% lower than IHD (RR = 0.56, n = 222), a difference in RR that indicates a strong trend for in-hospital mortality with borderline statistical significance (p = 0.069). Analysis of 100-day mortality also suggested a potential survival advantage for CRRT in all cohorts, particularly among patients in intensive care for more than five days who received at least 48 h of RRT (RR = 0.60, p = 0.062, n = 222). CONCLUSION: Applying the present methodology to outcomes at a single tertiary medical center, CRRT may appear to afford a survival advantage for patients with severe ARF treated in the ICU. Unless and until a prospective controlled trial is realized, the present data suggest potential survival advantages of CRRT and support broader application of CRRT among such critically ill patients.

APACHE↗

PubMed2002

Improving the assessment of gestational age in a Zimbabwean population.

OBJECTIVES: To evaluate the performance and the utility of using birthweight-adjusted scores of Dubowitz and Ballard methods of estimating gestational age in a Zimbabwean population. METHOD: The Dubowitz and the Ballard methods of estimating gestational age were administered to 364 African newborn infants with a known last menstrual period (LMP) at Harare Maternity Hospital. RESULTS: Both methods were good predictors of gestational age useful in differentiating term from pre-term infants. Our regression line was Y((LMP gestational age))=23.814+0.301*score for the Dubowitz and Y((LMP gestational age))=24.493+0.420*score for the Ballard method. Addition of birthweight to the regression models improved prediction of gestational age; Y((LMP gestational age))=23.512+0.219*score+0.0015*grams for Dubowitz and Y((LMP gestational age))=24.002+0.292*score+0.0016*grams for Ballard method. CONCLUSIONS: We recommend the use of our birthweight-adjusted maturity scales; the Dubowitz for studies of prematurity, and the Ballard for routine clinical practice.

Adolescent↗

PubMed2001

Potential risk factors for undifferentiated connective tissue disease among women: implanted medical devices.

A case-control study was conducted among 205 women in Michigan and Ohio who were diagnosed with undifferentiated connective tissue disease (UCTD) to investigate the significance of self-reported past exposures to implanted silicone-containing or non-silicone-containing medical devices. The 205 UCTD cases were compared with 2,095 controls who were sampled by random digit dialing. When silicone-containing devices, including shunts and catheters, were analyzed collectively, a significant association was observed (odds ratio (OR) = 2.81, 95% confidence interval (CI): 1.34, 5.89). The odds ratio for exposure to breast implants was increased, but not significantly (OR = 2.22, 95% CI: 0.65, 7.57). Among the non-silicone-containing devices, artificial joints (OR = 5.01, 95% CI: 1.60, 15.71) and orthopedic metallic fixation devices (OR = 1.95, 95% CI: 1.05, 3.60) were associated with UCTD. The estimations of risk associated with implanted medical devices in UCTD cases were explored in a comparison with 660 scleroderma patients who were ascertained concurrently in Michigan and Ohio. In general, the associations that were observed with non-silicone-containing devices, and more specifically with the fixation devices, persisted in the comparison of UCTD cases with scleroderma patients. The studies conducted among populations in Michigan and Ohio are intended to stimulate new hypotheses, innovative approaches, and the fostering of understanding of the environmental determinants of autoimmune disease.

Adolescent↗

PubMed2001

A methodology for analysing a repeated measures and survival outcome simultaneously.

A considerable body of literature has arisen over the past 15 years for analysing univariate repeated measures data. It is rare in applied biomedical research, however, for interest to be restricted to a single outcome measure. In previous work, Rochon considered the case of bivariate repeated measures data in which each outcome is a discrete or continuous random variable. A GEE model was prescribed to relate each set of repeated measures to important explanatory variables. The 'seemingly unrelated regression' model was then applied to combine the pair of GEE models into an overall analysis framework. In this paper, we extend this approach to the case in which one endpoint is a repeated measures outcome but the second is a survival endpoint. Estimation and hypothesis testing issues are addressed and the methodology is illustrated with an example.

Humans↗

PubMed2001

Quality of life in newly diagnosed glaucoma patients : The Collaborative Initial Glaucoma Treatment Study.

OBJECTIVE: The Collaborative Initial Glaucoma Treatment Study (CIGTS) was designed to determine whether patients with newly diagnosed open-angle glaucoma are better treated initially by medicine or immediate filtering surgery. This paper describes the quality-of-life (QOL) measurement approach, instruments included, and the CIGTS participants' QOL findings at the time of diagnosis. DESIGN: Baseline results from a randomized, controlled clinical trial. PARTICIPANTS: Six hundred seven patients from 14 clinical centers were enrolled. INTERVENTION: Patients randomized to initial medication received a stepped medical regimen (n = 307). Those randomized to initial surgery underwent a trabeculectomy (n = 300). The baseline interview was conducted before treatment initiation. All baseline and posttreatment QOL assessments were conducted by telephone from a centralized interviewing center. MAIN OUTCOME MEASURES: The primary outcome measure described in this paper was QOL. The QOL instrument is multidimensional and incorporates both disease-specific and generic measures, including the Visual Activities Questionnaire, Sickness Impact Profile, and a Symptom and Health Problem CHECKLIST: RESULTS: The correlations between QOL measures and clinical outcomes were in the expected direction, but relatively weak. At initial diagnosis, difficulty with bright lights and with light and dark adaptation were the most frequently reported symptoms related to visual function, whereas visual distortion was the most bothersome. Approximately half of the patients reported at least some worry or concern about the possibility of blindness. Within the Visual Activities Questionnaire, higher scores on the Peripheral Vision subscale were associated with more field loss (P < 0.01). In regression analyses controlling for sociodemographics and nonocular comorbidities, increased visual field loss was significantly associated with higher dysfunction among five disease-specific QOL measures (P < 0.05). CONCLUSIONS: Newly diagnosed glaucoma patients reported experiencing some visual function symptoms at the time of diagnosis that would not be intuitively expected based on clinical testing. Some discussion about the association between clinical presentation and worry about blindness may reduce unnecessary concern. These results provide the basis for long-term comparisons of the QOL effects of initial medical and surgical treatment for open-angle glaucoma.

Adult↗

PubMed2001

Interim clinical outcomes in the Collaborative Initial Glaucoma Treatment Study comparing initial treatment randomized to medications or surgery.

PURPOSE: To report interim outcome data, using all available follow-up through 5 years after treatment initiation, in the Collaborative Initial Glaucoma Treatment Study (CIGTS). DESIGN: Randomized clinical trial. PARTICIPANTS: Six hundred seven newly diagnosed glaucoma patients. METHODS: In a randomized clinical trial, 607 patients with newly diagnosed open-angle glaucoma were initially treated with either medication or trabeculectomy (with or without 5-fluorouracil). After treatment onset and early follow-up, patients were evaluated clinically at 6-month intervals. In addition, quality of life telephone interviews were conducted at similar frequency to the clinical visits. Patients in both arms of CIGTS were treated aggressively in an effort to reduce intraocular pressure (IOP) to a level at or below a predetermined target pressure specific for each individual eye. Visual field (VF) scores were analyzed by time-specific comparisons and by repeated measures models. MAIN OUTCOME MEASURES: VF loss was the primary outcome variable in CIGTS. Secondary outcomes of visual acuity (VA), IOP, and cataract were also studied. RESULTS: On the basis of completed follow-up through 4 years and partially completed through 5 years, VF loss did not differ significantly by initial treatment. Over the entire period of follow-up, surgical patients had a greater risk of substantial VA loss compared with medical patients. However, by 4 years after treatment, the average VA in the two groups was about equal. Over the course of follow-up, IOP in the medicine group has averaged 17 to 18 mmHg, whereas that in the surgery group averaged 14 to 15 mmHg. The rate of cataract requiring removal was greater in the surgically treated group. CONCLUSIONS: Both initial medical or initial surgical therapy result in about the same VF outcome after up to 5 years of follow-up. VA loss was greater in the surgery group, but the differences between groups seem to be converging as follow-up continues. When aggressive treatment aimed at substantial reduction in IOP from baseline is used, loss of VF can be seen to be minimal in general. Because 4 to 5 years of follow-up in a chronic disease is not adequate to draw treatment conclusions, these interim CIGTS outcomes do not support altering current treatment approaches to open-angle glaucoma.

Adrenergic beta-Antagonists↗

PubMed2001

The Collaborative Initial Glaucoma Treatment Study: interim quality of life findings after initial medical or surgical treatment of glaucoma.

OBJECTIVE: To present interim quality of life (QOL) findings in the Collaborative Initial Glaucoma Treatment Study (CIGTS) using all available follow-up through 5 years from treatment initiation. DESIGN: Randomized controlled clinical trial. PARTICIPANTS: Six hundred seven newly diagnosed patients with open-angle glaucoma from 14 clinical centers. INTERVENTION: Patients were randomly assigned to either initial medical therapy or initial trabeculectomy. After treatment initiation and early follow-up, patients received clinical and QOL evaluations at 6-month intervals. QOL assessments were administered by telephone at a centralized interviewing center. MAIN OUTCOME MEASURES: The CIGTS collected comprehensive QOL information that included both generic and vision-specific QOL measures. This article focuses on initial treatment group differences related to symptom reporting, as measured by a Symptom and Health Problem Checklist, and changes in daily visual functioning, as measured by the Visual Activities Questionnaire (VAQ). RESULTS: Across both treatment groups, there was an overall decline in the percent of participants reporting symptoms over time. Of 43 possible symptoms, 12 symptoms were reported with greater frequency by the surgically treated group and 7 symptoms more frequently by the medically-treated group. The surgical patients reported more total Symptom Impact Glaucoma (P = 0.005) and, in particular, more bother related to local eye symptoms. Very few treatment group differences were noted in visual functioning, although surgical patients reported more problems with activities related to their visual acuity (P = 0.024). The percentage of patients across treatment groups reporting worry about blindness was 50% at baseline but declined to approximately 25% over time. CONCLUSIONS: Overall, the QOL impact reported by the two treatment groups as measured by instruments used in this study is remarkably similar, with relatively few significant study group differences observed after up to 5 years of follow-up in the CIGTS. When significant differences in visual function have been detected using the VAQ, they are consistent with the clinical outcomes. To date, the most persistent QOL finding is the increased impact of local eye symptoms reported by the surgical group compared with the medical group. Although no changes are recommended in the treatment of newly diagnosed glaucoma patients at the time of this interim report, further follow-up will allow for more definitive answers to the QOL impact of these two treatment approaches.

Adrenergic beta-Antagonists↗

PubMed2001

Optimization of a fluorescent-based phosphor imaging dot blot DNA hybridization assay to assess E. coli virulence gene profiles.

To increase the efficiency and consistency in screening Escherichia coli for virulence genes, a Phosphor Imager was adopted for signal detection in Dot Blot DNA hybridization replacing X-ray film read by eye. We assessed not only the reliability of the instrument-based procedure, but the impact of going from an outcome measured by visualization on a semi-quantitative scale to a digitized readout on an interval scale. We analyzed technical and biological variability of the assay and the factors contributing to the variability. In spite of high variability both within and between membranes in the Phosphor Imager readings, we were able to define classification rules for gene presence that were remarkably consistent. Using the X-ray film signal detection procedure with Southern confirmation as a gold standard, we obtained a sensitivity and specificity of 87-99% for a rule requiring no retesting for all but one gene probe.

Autoradiography↗

PubMed2001

Obesity and gestational diabetes among African-American women and Latinas in Detroit: implications for disparities in women's health.

OBJECTIVE: to estimate the prevalence of gestational diabetes mellitus (GDM), obesity, and excessive weight gain during pregnancy among Latinas and African-American women in a large Detroit health system and explore risk factors associated with GDM and its implications. METHODS: Descriptive statistics, chi2 tests, analysis of variance, and logistic regression analyses were used to describe the prevalence of obesity, excessive pregnancy weight gain, and GDM and to assess factors associated with GDM risk in a cohort of 552 African-American women and 653 Latinas in a large Detroit health system. RESULTS: Women ranged in age from 14 to 47 years. Almost 47% of African-American women and 37% of Latinas were overweight or obese, and 53% of African-American women and 38% of Latinas gained excessive weight during pregnancy. The prevalence of GDM was 5.4% among Latinas and 3.9% among African-American women. After adjusting for other risk factors, Latinas were 2.5 times more likely than African Americans to develop GDM. Other independent risk factors were family history of diabetes, age, body mass index, and gestational weight gain before 28 weeks. CONCLUSION: Because most women have repeated contact with the health care system during and immediately after pregnancy, care providers have unique opportunities to identify and assist those who are at risk of obesity and diabetes.

Adolescent↗

PubMed2000

Sociopathy, gender, and treatment outcome among outpatient substance abusers.

Antisocial personality disorder (ASPD) may predict poor prognosis but gender/sociopathy relationships to prognosis remain unclear. This study investigated the effects of ASPD upon psychiatric and substance-related outcomes among 235 addiction treatment center outpatients. Prevalence rates for ASPD were similar for males (16%) and females (22%). At baseline, women and ASPD patients displayed greater substance-related and psychiatric severity. At 6-month follow-up, ASPD patients had greater severity on both measures than did patients without ASPD, but women now had equivalent psychiatric severity to men. After controlling for initial severity, ASPD was related to worse substance-related outcomes, but not to worse psychiatric outcomes.

Adolescent↗

PubMed2000

Psychosocial and sexual functioning in women with vulvodynia and chronic pelvic pain. A comparative evaluation.

OBJECTIVE: To determine whether women with vulvodynia differ from women with chronic pelvic pain and normal controls in their psychological functioning, somatic preoccupation, pain experience and sexual functioning. STUDY DESIGN: Cross-sectional, self-report study of women presenting to University of Michigan specialty and general clinics for the treatment of vulvodynia or chronic pelvic pain or seeking a routine gynecologic examination. All subjects completed questionnaires assessing demographic characteristics, pain, depressive symptoms, general affective state, marital adjustment, functional activity, somatic complaints, exposures, and medical and sexual history. Univariate analyses, chi 2 tests, analyses of variance and logistic regression were used to assess associations between these variables and the diagnostic category. RESULTS: Women with vulvodynia (n = 31) were similar to asymptomatic control women (n = 23) in demographic characteristics, sexual relationship variables, sexual behaviors, current and past depression, somatic sensitivity, and history of sexual or physical abuse. Women with chronic pelvic pain (n = 18) were younger and less educated than the other two groups and were more likely to have a history of physical and sexual abuse, to report recent depression and to screen positive for current depression, to have more work absences and to have more somatic complaints. CONCLUSION: Women with vulvodynia are psychologically similar to control women but differ significantly from women with chronic pelvic pain. A primary psychological cause of vulvodynia is not supported.

Adolescent↗

PubMed1999

Petroleum distillate solvents as risk factors for undifferentiated connective tissue disease (UCTD).

Occupational solvent exposure may increase the risk of connective tissue disease (CTD). The objective of this case-control study was to investigate the relation between undifferentiated connective tissue disease (UCTD) and solvent exposure in Michigan and Ohio. Women were considered to have UCTD if they did not meet the American College of Rheumatology classification criteria for any CTD but had at least two documented signs, symptoms, or laboratory abnormalities suggestive of a CTD. Detailed information on solvent exposure was ascertained from 205 cases, diagnosed between 1980 and 1992, and 2,095 population-based controls. Age-adjusted odds ratios (OR) and 95 percent confidence intervals (CI) were calculated for all exposures. Among 16 self-reported occupational activities with potential solvent exposure, furniture refinishing (OR = 9.73, 95 percent CI 1.48-63.90), perfume, cosmetic, or drug manufacturing (OR = 7.71, 95 percent CI 2.24-26.56), rubber product manufacturing (OR = 4.70, 95 percent CI 1.75-12.61), work in a medical diagnostic or pathology laboratory (OR = 4.52, 95 percent CI 2.27-8.97), and painting or paint manufacturing (OR = 2.87, 95 percent CI 1.06-7.76) were significantly associated with UCTD. After expert review of self-reported exposure to ten specific solvents, paint thinners or removers (OR = 2.73, 95 percent CI 1.80-4.16) and mineral spirits (OR = 1.81, 95 percent CI 1.09-3.02) were associated with UCTD. These results suggest that exposure to petroleum distillates increases the risk of developing UCTD.

Adolescent↗

PubMed1997

A case-control study of self-reported exposures to pesticides and pancreas cancer in southeastern Michigan.

A case-control study of pancreas cancer in residents, aged 30-79 years, of 18 counties in southeastern Michigan was conducted to investigate the risks of exposure to DDT and related materials in the general population. Sixty-six people with cytologically diagnosed pancreas cancer were identified using 7 participating hospitals in metropolitan Detroit and Ann Arbor. One hundred and thirty-one controls were frequency-matched to the cases on age, sex, ethicity and county of residence by random-digit dialing. All study participants were administered a questionnaire to assess life-time exposure to pesticides from both environmental and occupational sources, family history of cancer, past medical history, smoking history and demographic information. A statistically significant increased risk was found for self-reported exposure to ethylan (1,1-dichloro-2,2-bis(4-methoxyphenyl) ethane). Increased odds ratios were observed for self-reported exposures to chloropropylate and DDT, as well as for the summary group of organochlorine pesticides which included all of these materials, though these associations were not significant.

Adult↗

PubMed1997

Racial differences in scleroderma among women in Michigan.

OBJECTIVE: To examine racial differences in disease onset, extent, manifestations, and survival among women with scleroderma. METHODS: A retrospective cohort study of women with scleroderma, diagnosed in Michigan between 1980 and 1991, was conducted. Clinical, laboratory, and demographic data were abstracted from the patients' medical records. RESULTS: A total of 514 women with scleroderma were identified: 117 (23%) were black and 397 (77%) were white. Among black women, the mean age at diagnosis was lower (44.5 years versus 51.5 years; P < 0.001) and diffuse disease was more common (49.6% versus 24.9%; P < 0.001) than among white women. The overall incidence of scleroderma was 14.1 per million per year: 22.5 per million per year in black women versus 12.8 per million per year in white women (P < 0.001). Pericarditis (P = 0.009), pulmonary hypertension (P < 0.001), pleural effusions (P = 0.01), myositis (P = 0.02), and an erythrocyte sedimentation rate >40 mm/hour (P < 0.001) were more frequent among black women, while white women were more likely to have digital infarctions (P < 0.001). Survival at 7 years from diagnosis was 72.5% among black women and 77.6% among white women. Age-adjusted survival was significantly reduced among black women (P = 0.033), most likely because of increased diffuse involvement. Survival among those with renal or pulmonary involvement was also significantly reduced. CONCLUSION: Black women with scleroderma were significantly more likely than white women to develop diffuse disease, be diagnosed at a younger age, have a higher incidence of inflammatory features, and have a worse age-adjusted survival rate.

Adolescent↗

PubMed1997

Transmission of uropathogens between sex partners.

Epidemiologic evidence and several case reports suggest that Escherichia coli causing urinary tract infection (UTI) may be transmitted between sex partners. In order to test this hypothesis, urinary, vaginal, and fecal E. coli isolates from 19 women with UTI were compared with E. coli found in random initial voids from their most recent male sex partner. E. coli was isolated from 4 of 19 male sex partners. In each case, the E. coli isolated from the man was identical by pulsed-field gel electrophoresis and bacterial virulence profile to the urinary E. coli from his sex partner.

Adult↗

PubMed1996

Cross-over trials with censored data.

Cross-over trials assign two or more treatments sequentially to the same subject; groups of subjects receive different treatment sequences. Both parametric and non-parametric methods of inference are available for cross-over trials with complete data. In this paper we develop methods for estimation and testing in cross-over trials with censored data, based partly on methods used for complete data. Our estimator is consistent for the true effects. Simulation results show that both of our proposed tests have approximately nominal size. We compare our procedures to a method for cross-over designs based on Cox regression proposed by France, Lewis and Kay. We demonstrate that our method of estimation is superior to the Cox-based method, which has considerable bias. Both of the tests presented here have more power than the Cox-based tests in all of the situations we investigated. The estimation and test procedures apply to other designs, such as parallel trials and repeated measures designs.

Bias↗