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PubMed2006

Screening rates and characteristics of health plan members who respond to screening reminders.

INTRODUCTION: Preventive screening is widely recognized as a key component of cost-effective, high-quality health care. Even so, national screening for cancer, diabetes, and cholesterol falls far short of U.S. Preventive Services Task Force recommendations. Although evidence has shown that reminder programs improve preventive screening rates, this study is one of the first to examine the characteristics of health plan members who respond to screening reminders. METHODS: The study sample included active members of a large health plan in Hawaii who were identified by an algorithm as not having received one or more recommended screenings based on age and sex criteria (2000-2003) for breast cancer (n = 44,331), cervical cancer (n = 73,875), colon cancer (n = 131,860), diabetes (n = 86,216), and cholesterol (n = 54,843). Statistical analyses were conducted using Cox proportional hazard and logistic regression models. In the proportional hazard models, reminder letters were treated as time-varying exposures. Hazard ratios, or rate ratios, were used to examine the relationship between health plan member and physician characteristics and the likelihood of responding to the reminders. The effects of additional or multiple reminders among health plan members receiving more than one reminder were examined in multivariable regression models. RESULTS: The impact of health plan member characteristics and number of office visits on the response to reminders varied among the five health-screening types. Health plan members responded better to reminders for diabetes screening than for colon cancer screening. Members sent their second annual reminders were less likely to obtain screening than members sent their first reminder. Members receiving their third (or more) annual reminder were especially recalcitrant. CONCLUSION: Our findings suggest that the response to reminders differs according to patient characteristics. In particular, targeted interventions may be needed to encourage screening for younger and healthier members whose response rate to reminders was low. Further research is needed to determine how health plans can best reach members who do not respond to patient reminders.

Aged↗

PubMed1997

Serum uric acid as an index of impaired oxidative metabolism in chronic heart failure.

BACKGROUND: Elevated serum uric acid concentrations have been observed in clinical conditions associated with hypoxia. Since chronic heart failure is a state of impaired oxidative metabolism, we sought to determine whether serum uric acid concentrations correlate with measures of functional capacity and disease severity. METHODS: Fifty nine patients with a diagnosis of chronic heart failure due to coronary heart disease (n = 34) or idiopathic dilated cardiomyopathy (n = 25) and 20 healthy controls underwent assessment of functional capacity. Maximal oxygen uptake (MVO2) and regression slope relating to minute ventilation to carbon dioxide output (VE-VCO2) were measured during a maximal treadmill exercise test. Metabolic assessment consisted of measuring serum uric acid and fasting lipids, and insulin sensitivity, obtained by minimal modelling analysis of glucose and insulin responses during an intravenous glucose tolerance test. Clustering of indices of functional disease capacity and metabolic factors was explored using factor analysis and multivariate regression analysis. RESULTS: Compared to 20 healthy controls, patients with chronic heart failure had a 52% lower MVO2 (P < 0.001), 56.8% higher serum uric acid concentrations (P < 0.001) as well as a 60.5% lower insulin sensitivity (P < 0.001). Salient univariate correlations in the chronic heart failure group included serum uric acid concentrations with exercise time during the exercise test (r = -0.53), MVO2 (r = -0.50) (both P < 0.001), VE-VCO2 slope (r = 0.45), and NYHA functional class (r = 0.36) (both P < 0.01). In factor analysis of the chronic heart failure group, serum uric acid formed part of a principal cluster of metabolic variables which included MVO2 and VE-VCO2 slope. In multivariate regression analysis, serum uric acid concentrations emerged as a significant predictor of MVO2, exercise time (both P < 0.001,) VE-VCO2 slope and NYHA functional class (both P < 0.02), independent of diuretic dose, age, body mass index, serum creatinine, alcohol intake, plasma insulin levels, and insulin sensitivity index. CONCLUSIONS: There is an inverse relationship between serum uric acid concentrations and measures of functional capacity in patients with cardiac failure. The strong correlation between serum uric acid and MVO2 suggests that in chronic heart failure, serum uric acid concentrations reflect an impairment of oxidative metabolism.

Aged↗

PubMed2006

Low back pain and occupation among Irish health service workers.

BACKGROUND: The health services sector has been identified as a high-risk work sector for low back pain (LBP) and related absenteeism. AIMS: To establish levels and predictors of LBP prevalence and associated sick leave among health service workers. To identify if levels of LBP or related absenteeism differ between occupational groups. METHODS: A postal survey using a standardized questionnaire and disproportionate random sampling of occupational groups was conducted at a single Dublin hospital. Overall hospital LBP prevalence and sickness absence were calculated using weighted analysis methods. Univariate analysis included the use of Chi-square, Fisher's exact and Mann-Whitney tests. Multivariate logistic regression techniques were used to explore for independent predictors of lifetime LBP prevalence and LBP-related sickness absence. RESULTS: An overall response rate of 62% (n = 246) was achieved. Lifetime, annual and point prevalence rates for the hospital employees were calculated at 46, 30 and 15.5%, respectively. No significant difference in prevalence was found between occupational groups but sick leave did differ with the highest level among general support and nursing staff. Multivariate analysis confirmed that occupation was an independent predictor for LBP-related sick leave (P < 0.05). CONCLUSIONS: LBP prevalence rates did not differ significantly between occupational groups but occupation was found to be an independent predictor of LBP-related sick leave. Involvement in manual handling did not predict either LBP or related sick leave.

Absenteeism↗

PubMed1991

The influence of preoperative patient characteristics on early and late survival following cardiac transplantation.

In an attempt to identify the preoperative factors that influence survival following cardiac transplantation, we retrospectively analyzed multiple demographic, clinical, and hemodynamic data of 301 consecutive patients who underwent cardiac transplantation between December 1980 and July 1988 (cyclosporine era). Univariate and multivariate regression analyses revealed that the two most deleterious risk factors for premature death following transplantation were pulmonary hypertension not responsive to vasodilator challenge and preoperative requirement of hemodynamic support (intravenous inotropes or mechanical assistance). The combination of these two independent risk factors was an even stronger predictor of mortality (relative risk, 6:1; p less than 0.0001): the 3-month actuarial survival rate of the 20 patients with this combination was 30.3% versus 78.4% of the 47 patients with only pulmonary hypertension, 87.9% of the 42 patients with only the requirement of hemodynamic support, and 95.3% of the 172 patients with neither of these two risk factors. The difference in postoperative mortality between patients with versus those without these two risk factors is due to a higher rate of fatal infectious complications: six of 20 patients (30%) with both risk factors died from infection within 3 months after transplant compared with three deaths among 172 patients (1.7%) with neither of these risk factors. The majority of fatal infections were pulmonary. There were significantly more fatal and nonfatal infectious episodes in patients with one or both of these risk factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2003

A two centre study of the dose-response relation for transscleral diode laser cyclophotocoagulation in refractory glaucoma.

BACKGROUND/AIMS: Transscleral diode laser cyclophotocoagulation ("cyclodiode") is widely used to treat refractory glaucoma. The main aims of this study were to investigate the dose-response relation of cyclodiode and to evaluate possible predictive factors that would help establish optimum treatment parameters. METHODS: A retrospective analysis of the case notes of 263 eyes of 238 consecutive patients who underwent transscleral diode laser cyclophotocoagulation at two centres was undertaken. RESULTS: Mean intraocular pressure (IOP) decreased significantly from 40.7 mm Hg (SD 13.7) before cyclodiode therapy to 17.7 mm Hg (SD 10.9) post-treatment, a reduction of 52.6% (p = 0.0001). Following cyclodiode, 89% of patients achieved an IOP of less than 22 mm Hg or a greater than 30% drop in IOP. Hypotony occurred in 9.5% of patients, 76% of whom had neovascular glaucoma. A linear dose relation response was found for the 122 eyes with neovascular glaucoma (p = 0.001) but not for the group as a whole. Treatment failure was associated with male sex (multivariate regression analysis, p = 0.008) and low mean energy per treatment session (univariate analysis alone, p = 0.016). High pretreatment IOP (p = 0.031) and high mean energy per treatment episode (p = 0.001) appeared to be associated with the occurrence of hypotony, although multivariate analysis did not support this finding. CONCLUSION: Cyclodiode therapy is highly effective but there is a significant risk of hypotony, which may be reduced by applying lower energy in cases of very high pretreatment IOP and in neovascular glaucoma. The dose-response association remains unpredictable, although a linear relation was found for neovascular glaucoma.

Adolescent↗

PubMed1997

Pediatricians' experience with and attitudes toward firearms. Results of a national survey.

BACKGROUND: In 1992, the American Academy of Pediatrics issued statements calling for aggressive actions to reduce the dangers of firearms to children and adolescents, including removing handguns from homes with children and working toward a ban on the manufacture, sale, and private possession of handguns. OBJECTIVES: To determine the extent to which pediatricians support these positions against firearms and to describe the demographic and practice determinants of their views. INTERVENTIONS: In 1994, data were obtained from 982 pediatricians involved in direct patient care in a national, random-sample survey of American Academy of Pediatrics members (response rate, 68.9%). This article focuses on 4 areas: (1) recent experience treating gun injuries, (2) attitudes toward legislation to reduce the availability of guns, (3) attitudes toward gun safety counseling by pediatricians, and (4) current gun safety counseling practices. Wherever possible, chi 2 and t tests were used to compare responses to a similar 1988 survey of American Academy of Pediatrics members. Logistic regression was used to examine the multivariate relationships between the outcome variables and demographic and practice characteristics of the responding pediatricians. RESULTS: Almost 1 in 5 pediatricians treated a gun injury in the past 12 months. In 1988, 86.5% of pediatricians supported restricting the sale and possession of handguns; in 1994, support for such legislation increased to 92.5% (P < .01). Also in 1994, 76% supported banning the sale or possession of handguns. Most respondents (82%) believe anticipatory guidance on firearm safety can reduce injury and death; 95% support asking parents to unload and lock firearms, and 66% support encouraging parents to remove handguns from the home. Current counseling practices lag behind attitudinal support of anticipatory guidance on firearm safety (eg, half of respondents report never identifying families with firearms in the home). Demographic factors as well as professional experience were found to affect attitudes (eg, women, older pediatricians, and those who did not own guns were more likely to support gun-control legislation; and pediatricians who have recently treated gun injuries and those practicing in the inner city are more likely to counsel families about gun safety). CONCLUSIONS: The data indicate that practicing pediatrician overwhelmingly agree that handguns in the home are hazardous and that steps should be taken to reduce this hazard through legislation and patient counseling. They support the policies on firearms and handguns of the American Academy of Pediatrics; most support even the strongest recommendation, which is a ban on handguns. A substantial lag between attitudes that favor counseling about firearms and reported practices indicates the need for further training in and evaluation of firearm counseling in office settings.

Adolescent↗

PubMed2005

Pelvic Organ Support Study (POSST) and bowel symptoms: straining at stool is associated with perineal and anterior vaginal descent in a general gynecologic population.

OBJECTIVE: The purpose of this study was to evaluate the association of constipation symptoms and anal incontinence with vaginal wall and pelvic organ descent in a general gynecologic population. STUDY DESIGN: In this multicenter, cross-sectional study, 1004 women attending routine gynecologic healthcare underwent pelvic organ prolapse quantification (POPQ) measurements, and were surveyed regarding anal incontinence, digitation, < 2 bowel movements (BMs)/week, and > 25% frequency of: straining, hard/lumpy stools, and incomplete emptying. Constipation scores reflected the sum of positive responses. Associations between POPQ measurements (Ba, C, Bp, gh+pb), constipation scores, and anal incontinence were evaluated using multivariable regression. RESULTS: Of 119 women with Bp > or = -1.00, 47% reported no constipation symptoms. Hard/lumpy stools (26%), incomplete emptying (24%), and straining (24%) were more prevalent; fewer women reported < 2 BMs/week (15%) or digitation (7%). Constipation scores were weakly correlated with Bp, gh+pb (both r < .1, P < .02). Women reporting > or = 2 symptoms had greater gh+pb measurements than women reporting 0 or 1 symptom (P = .03). Women with anal incontinence had greater gh+pb and gh values than women without anal incontinence (P < .01). POPQ measurements were regressed separately onto (1) total constipation scores, (2) dichotomized scores, and (3) individual symptoms, with BMI, age, number of vaginal deliveries (NVD), weight of largest vaginal delivery (WLVD), race, hysterectomy, study site, and income included as covariates. Total constipation scores and dichotomized scores were nonsignificant in all models. With regard to individual symptoms, straining at stool was significant in the models for Ba and gh+pb, with greater Ba and gh+pb measurements among strainers relative to nonstrainers. CONCLUSION: Most associations between bowel symptoms and vaginal or pelvic organ descent were weak. After controlling for important covariates, straining at stool remained associated with anterior vaginal wall and perineal descent.

Adult↗

PubMed2006

Gastrointestinal graft-versus-host disease in recipients of autologous hematopoietic stem cells: incidence, risk factors, and outcome.

Graft-versus-host disease (GVHD) is seen in skin, intestinal mucosa, and liver after autologous stem cell transplantation. We reviewed 681 consecutive patients to estimate the probability of gastrointestinal (GI) GVHD, response to treatment, risk factors for development, and effect on survival. GI GVHD was defined by persistent symptoms, mucosal abnormalities at endoscopy, and histology showing apoptotic crypt cells with or without lymphoid infiltrates. The proportion of patients with GI GVHD was 90/681 (13%). Nausea and vomiting occurred in 90% and diarrhea in 40%. The mean time to developing symptoms was day +15, that to histologically proven diagnosis was day +42, and that to starting prednisone treatment was day +45 after stem cell infusion. Treatment with a short course of prednisone effected durable responses in 79% of patients, and an additional 18% responded to a second course of prednisone. A multivariable logistic regression model demonstrated that the combined factor of a diagnosis of breast cancer or hematologic malignancy and female sex was statistically significantly associated with the probability of GI GVHD (P = .003). Survival in patients with GI GVHD was not statistically different than that in those without GVHD. We conclude that women with breast cancer or hematologic malignancy are more likely to develop GI GVHD after autologous transplantation, and that treatment with prednisone was effective.

Adult↗

PubMed2005

Increased ambulatory pulse pressure is a strong risk factor for coronary endothelial vasomotor dysfunction.

OBJECTIVES: This study was aimed to determine the relationship between pulse pressure (PP) and coronary vasomotor dysfunction, a predictor of coronary events. BACKGROUND: Pulse pressure is a strong risk factor for coronary artery disease (CAD). However, the mechanisms by which an increase in PP affects the pathogenesis of CAD are unclear. METHODS: Ambulatory blood pressure (BP) monitoring for 24 h was performed in 103 consecutive patients with normal coronary angiograms (51 hypertensive and 52 normotensive; age 42 to 70 years). The relationship between changes in coronary arterial diameter and blood flow during an intracoronary infusion of acetylcholine (ACh) (5, 10, 50 microg/min), and BP parameters, and other traditional risk factors was evaluated using univariate and multivariate linear regression analyses. RESULTS: With multivariate analyses, the 24-h PP showed an inverse correlation with the epicardial coronary dilator response to ACh independently of other covariates including age, smoking, and 24-h systolic BP in normotensive as well as hypertensive patients. Furthermore, multivariate analysis showed that the 24-h PP was inversely and independently correlated with the increase in coronary blood flow in response to ACh. The dilator response of epicardial coronary arteries to nitrate was not significantly correlated with 24-h PP. CONCLUSIONS: Increased 24-h PP is independently associated with endothelial vasomotor dysfunction in conduit and resistance coronary arteries irrespective of the presence of hypertension. Increased ambulatory PP may have an intimate relation to coronary endothelial vasomotor dysfunction.

Acetylcholine↗

PubMed2001

Chemometric modeling of neurotransmitter amino acid separation in normal and reversed migration micellar electrokinetic chromatography.

A chemometric experimental design has been applied for the optimization of neurotransmitter amino acid separation in capillary electrophoresis. The optimizations were carried out for normal micellar electrokinetic chromatography (N-MEKC) and reversed migration micellar electrokinetic chromatography (RM-MEKC). In order to optimize three separation factors and study the interaction between factors, a response function was optimized via searching its optimum (minimum/maximum). For this purpose a central composite design with multivariate linear regression (MLR) analysis was utilized. Modeling with good regression coefficients from the MLR adequately described the interaction of factors such as background electrolyte and sodium dodecylsulfate concentrations which had a large impact on selectivity and migration behaviors. Similar optimal conditions regarding resolution and number of theoretical plates but different retention behaviors as a function of background electrolyte and micellar concentrations were observed for N-MEKC and RM-MEKC. Improved overall performance from the RM-MEKC separation of five neurotransmitter acids, superior to N-MEKC, is demonstrated in terms of repeatability, peak symmetry, sensitivity, and in particular, impurity determination in an overloaded separation system.

Amino Acids↗

PubMed2003

Determinants of late prenatal care initiation by African American women in Washington, DC.

OBJECTIVES: The objective of this study was to identify the determinants of late prenatal care (PNC) initiation among minority women in Washington, DC. METHODS: DC-resident, African American women (n = 303) were recruited at 14 PNC facilities, representing the various types of PNC facilities located in DC: 4 hospital-based clinics, 5 community-based clinics, and 5 private practices. The women were interviewed at their first prenatal care visits to determine their perceptions of 63 barriers, motivators and facilitators influencing PNC initiation; substance use; and sociodemographic background. PNC initiation was classified as early (prior to the 20th week of gestation) or late (after the 20th week of gestation). The responses of women who initiated PNC early versus late were compared using bivariate and multivariate statistical procedures. Classification and Regression Trees analysis was used to identify groups at risk of late initiation. RESULTS: Variables contributing to late PNC initiation included maternal age not between 20 and 29 years, unemployment, no history of previous abortions, consideration of abortion, lack of money to pay for PNC, and no motivation to learn how to protect ones health. Three risk groups for late PNC initiation included 1) women consideringabortion and not employed outside their homes; 2) women not considering abortion who had no previous abortion experience; and 3) teenagers not considering abortion and with no previous abortions. CONCLUSIONS: The results of this study indicate that psychosocial barriers are more important than structural barriers. Of the psychosocial barriers, the major determinants of late PNC initiation were consideration of abortion and previous abortion experience.

Abortion, Induced↗

PubMed2004

Vascular endothelial growth factor (VEGF) in leptomeningeal metastasis: diagnostic and prognostic value.

This study examined the diagnostic and prognostic value of vascular endothelial growth factor (VEGF) levels in the cerebrospinal fluid (CSF) of 39 patients with leptomeningeal metastasis (LM). Vascular endothelial growth factor levels at diagnosis were significantly higher in patients with LM (median 359 pg ml(-1)) than in patients with other neurological diseases (median <25 pg ml(-1)). The specificity of VEGF levels above 250 pg ml(-1) for LM was high (98.3%), while the sensitivity was low (51.4%; 73% for VEGF values above 100 pg ml(-1)). In 49% of the LM patients, particularly with lymphoma or medulloblastoma, VEGF levels were below 250 pg ml(-1) and thus in the range of VEGF levels in other neurological diseases. Vascular endothelial growth factor levels correlated significantly with CSF lactate and albumin. Vascular endothelial growth factor levels mirrored the clinical course with a marked reduction in response to therapy and an increase at relapse in some patients who had serial CSF samples available. Multivariate Cox regression analysis showed VEGF below 100 pg ml(-1) (relative risk (RR)=4.24, P=0.0002) and age below 60 years (RR=2.5, P=0.004) to be associated with longer survival in LM. In conclusion, CSF VEGF levels in LM vary considerably. High VEGF levels have a very high specificity for LM and may help to establish the diagnosis. The role of VEGF as a predictor of outcome should be substantiated in prospective studies.

Biomarkers, Tumor↗

PubMed2000

The role of competence factors in reducing the future risk of drug use among young Swedish men.

AIMS: To investigate the importance of individual competences and risk factors at the age of 18 for future risk of substance misuse. Both behavioural and home-background risk factors were studied. DESIGN AND PARTICIPANTS: The study group consisted of 7577 18-year-old Swedish conscripts followed for substance misuse up to the age of 36. Information on competence and risk factors was obtained from a survey at conscription. Records of drug use were obtained from official registers; 158 (2%) people were identified as serious adult substance misusers. FINDINGS: Good emotional control and cognitive and social capacity were significantly associated with reduced risk of adult drug use whereas early contact with the police or juvenile authorities and alcohol misuse were the most powerful predictors for increased risk of adult drug misuse in multivariate analyses. The proportion of registered adult drug misuse in conscripts with multiple behavioural risk factors was 13.3% in those with drug experiences in late adolescence, compared with 2.6% in those with no earlier drug-experiences. Subjects with multiple behavioural and home-background risk factors but more than one competence were less likely to develop future substance misuse than those with only one or no competence factor. When analysed in relation to behavioural risks, competence factors are most effective in reducing drug use among subjects belonging to the high-risk category, whereas when analysed in relation to home-background risks personal competences are effective in low, medium and high-risk groups. CONCLUSION: Competences can protect against the development of serious problematic drug use and thus must be considered in preventive efforts.

Adaptation, Psychological↗

PubMed2006

Diagnostic value of vestibulo-ocular reflex parameters in the detection and characterization of labyrinthine lesions.

OBJECTIVE: To evaluate the power of various parameters of the vestibulo-ocular reflex (VOR) in detecting unilateral peripheral vestibular dysfunction and in characterizing certain inner ear pathologies. STUDY DESIGN: Prospective study of consecutive ambulatory patients presenting with acute onset of peripheral vertigo and spontaneous nystagmus. SETTING: Tertiary referral center. PATIENTS: Seventy-four patients (40 females, 34 males) and 22 normal subjects (11 females, 11 males) were included in the study. Patients were classified in three main diagnoses: vestibular neuritis: 40; viral labyrinthitis: 22; Meniere's disease: 12. METHODS: The VOR function was evaluated by standard caloric and impulse rotary tests (velocity step). A mathematical model of vestibular function was used to characterize the VOR response to rotational stimulation. The diagnostic value of the different VOR parameters was assessed by uni- and multivariable logistic regression. RESULTS: In univariable analysis, caloric asymmetry emerged as the most powerful VOR parameter in identifying unilateral vestibular deficit, with a boundary limit set at 20%. In multivariable analysis, the combination of caloric asymmetry and rotational time constant asymmetry significantly improved the discriminatory power over caloric alone (p<0.0001) and produced a detection score with a correct classification of 92.4%. In discriminating labyrinthine diseases, different combinations of the VOR parameters were obtained for each diagnosis (p<0.003) supporting that the VOR characteristics differ between the three inner ear disorders. However, the clinical usefulness of these characteristics in separating the pathologies was limited. CONCLUSION: We propose a powerful logistic model combining the indices of caloric and time constant asymmetries to detect a peripheral vestibular loss, with an accuracy of 92.4%. Based on vestibular data only, the discrimination between the different inner ear diseases is statistically possible, which supports different pathophysiologic changes in labyrinthine pathologies.

Adolescent↗

PubMed2006

Tacrolimus/mycophenolate mofetil improved natural killer lymphocyte reconstitution one year after kidney transplant by reference to cyclosporine/azathioprine.

BACKGROUND: Recently introduced immunosuppressive drugs are more potent to control graft rejection, but current concerns are raised regarding their potential to increase long-term neoplastic and infectious complications. Considering the role of B, T, or natural killer (NK) lymphocyte in controlling alloreactive, anti-infectious, and antitumoral immune responses, we compared the impact of two immunosuppressive regimens on lymphocyte subsets one year following kidney transplant. METHODS: Multivariate regression analysis of variables affecting lymphocyte subset counts was retrospectively performed on 91 kidney-transplanted patients, analyzed before graft, at day 15 and 1-year postgraft. These patients were included in a randomized prospective open trial comparing tacrolimus/mycophenolate mofetil (FK/MMF) versus cyclosporine/azathioprine (CSA/Aza), both used in association with rabbit antithymocyte globulines (rATG) induction and prednisone. RESULTS: Fifteen days postgraft, severe T and NK lymphocyte depletion were observed in all patients, while B cell counts were selectively higher in the FK/MMF group as compared to before graft. One-year posttransplant, NK cell counts and NK cell cytotoxicity was significantly higher in patients receiving FK/MMF therapy, as compared to CSA/Aza. Cytomegalovirus (CMV) infection during the first year posttransplant was also associated to higher NK, CD8, and CD4CD8 T cell counts at month 12. CONCLUSIONS: In addition to its higher potential in preventing graft rejection, we show that after one year of transplant, FK/MMF better preserves NK innate immune effector cells and their cytotoxic potential. These data prompt to further evaluate the role of NK cells in relation to antiviral and tumoral surveillance of transplanted patients, which are common complications of long-term immunosuppression.

Adult↗

PubMed1996

Urinary incontinence in rural older women: prevalence, incidence and remission.

OBJECTIVES: To determine the prevalence, incidence, and remission rates of urinary incontinence in a large group of older women over a 6-year time span and to assess factors associated with incontinence incidence and remission. DESIGN: Longitudinal cohort study. SETTING: Two rural counties in Iowa. PARTICIPANTS: 2025 women aged 65 years or older residing in rural Iowa, enrolled in the Iowa 65+ Rural Health Study of EPESE (Establishment of Populations for Epidemiologic Studies of the Elderly) were interviewed in person annually for 6 years; specific responses to queries about urinary incontinence were given at baseline, 3-, and 6-year intervals. MEASUREMENTS: Conditional multivariate logistic regression analysis was done to assess the relationship between incontinence symptoms and various factors previously found to be related to incontinence. RESULTS: The baseline prevalence of urge incontinence was 36.3%, and of stress incontinence it was 40.3%. For urge incontinence, the 3-year incidence and remission rates between the third and sixth years were 28.5% and 22.1%, respectively. For stress incontinence, the 3-year incidence and remission rates between years 3 and 6 were 28.6% and 25.1%, respectively. Seventy-six percent and 84% of women who reported no urge or stress incontinence, respectively, at the baseline interview were continent at both follow-up interviews. The only significant factors related to changes in incontinence status were age, which was associated with an increased incidence of urge incontinence (OR 1.11, P = .017, 95% CI 1.019-1.203), and improvement in activities of daily living, which was associated with a increased remission of urge incontinence (OR 0.50, P = .015, 95% CI 0.28-0.9) CONCLUSION: In some older women, urinary incontinence is a dynamic state, with women moving back and forth along a continuum between continence and incontinence. These results are tempered by limitations of the study, which include its questionnaire design and lack of ability to detect potential treatment effect.

Aged↗

PubMed2001

Prognostic variables in canine multicentric lymphosarcoma.

This paper presents the results of a prospective study to investigate the prognostic value of clinical staging, histological grading, immunophenotype, mitotic count and average numbers of argyrophilic nucleolar organiser region counts in dogs with multicentric lymphosarcoma treated with a standard chemotherapy protocol comprising vincristine, cyclophosphamide and prednisolone. Forty-nine dogs were treated according to the study protocol. Univariate and multivariate analysis with regression modelling was used to evaluate the prognostic importance of patient and tumour variables upon tumour response and relapse-free survival. Thirty-seven dogs (76 per cent) achieved a complete remission, seven (14 per cent) a partial remission and five (10 per cent) failed to respond to treatment. None of the variables examined had a statistically significant effect upon tumour response. Tumour immunophenotype was the only parameter found to have a significant influence on patient survival, the hazard ratio for T-cell versus B-cell immunophenotype was 3.99 with 95 per cent confidence interval from 1.399 to 11.372, P = 0.035.

Animals↗

PubMed1997

Selecting optimal experiments for multiple output multilayer perceptrons.

Where should a researcher conduct experiments to provide training data for a multilayer perceptron? This question is investigated, and a statistical method for selecting optimal experimental design points for multiple output multilayer perceptrons is introduced. Multiple class discrimination problems are examined using a framework in which the multilayer perceptron is viewed as a multivariate nonlinear regression model. Following a Bayesian formulation for the case where the variance-covariance matrix of the responses is unknown, a selection criterion is developed. This criterion is based on the volume of the joint confidence ellipsoid for the weights in a multilayer perceptron. An example is used to demonstrate the superiority of optimally selected design points over randomly chosen points, as well as points chosen in a grid pattern. Simplification of the basic criterion is offered through the use of Hadamard matrices to produce uncorrelated outputs.

Algorithms↗