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PubMed1997

Visual outcomes prognosticators in juvenile rheumatoid arthritis-associated uveitis.

PURPOSE: The purpose of the study is to delineate the visual prognosticators in juvenile rheumatoid arthritis-associated uveitis. METHODS: The records of 43 patients with juvenile rheumatoid arthritis-associated uveitis who were observed for at least 6 months were studied retrospectively. Bivariate and multivariate statistical models were applied to more than 40 parameters to determine the relative odds of visual rehabilitation among patients with each characteristic. RESULTS: Thirty-seven (86%) patients were females and 6 (14%) males. The mean known age of uveitis onset was 13 years, with females having, on average, 4 years earlier onset of disease compared to males (P = 0.04). Ninety-three percent had chronic, 5% had recurrent, and 2% had an acute monophasic disease course. Of the 76 affected eyes, 93% were nongranulomatous and 97% had iridocyclitis. The mean overall duration of uveitis was 146 months, with females suffering from a significantly longer duration of active disease than did males (P < 0.001). Nineteen (44%) patients underwent cataract extraction, and 16 (37%) underwent vitrectomy. Thirty (70%) of the patients experienced visual improvement with their therapy. When controlling for potential confounders, male sex (P = 0.006), shorter duration of uveitis (P = 0.007), older age at disease onset (P = 0.02), and a shorter delay in presentation to a subspecialist (P = 0.02) were associated significantly with visual acuity improvement. Visual acuity at presentation (P = 0.001), use of systemic nonsteroidal anti-inflammatory drugs (P = 0.01), older age at disease onset (P = 0.02), absence of glaucomatous neuropathy (P = 0.02), and male sex (P = 0.03) were correlated strongly with a final visual acuity outcome of 20/40 or better. CONCLUSION: Juvenile rheumatoid arthritis-associated uveitis is a serious disease with a guarded visual prognosis. It is hoped that increased awareness of its prognosticators will lead to treatment and referral patterns that have the best chance of minimizing the likelihood of visual impairment in patients with juvenile rheumatoid arthritis.

Acute Disease↗
PubMed2006

Acute limb ischemia associated with type B aortic dissection: clinical relevance and therapy.

BACKGROUND: The goal of the current study is to characterize the presentation, therapy, and outcomes of acute limb ischemia (ALI) associated with type B aortic dissection (AoD). METHODS: The prospective/retrospective International Registry for Acute Aortic Dissection (IRAD) database and a single institutional database were queried for all patients with type B AoD from 1996 to 2002. Univariate and multivariate statistics were used to delineate factors associated with morbidity and mortality outcomes. RESULTS: According to the IRAD data (n = 458), the mean age of patients was 64 years, and 70% were men. The overall mortality was 12%; of these, 6% had ALI. Pulse (3-fold) and neurologic deficits (5-fold) were more common in those with ALI (P < .001). Endovascular, but not surgical therapy, was more commonly performed in patients with ALI compared with those without ALI (31% vs 10%, P = .004). No difference in age, race, gender, or origin of dissection was observed. ALI was associated with acute renal failure (odds ratio [OR] = 2.7; 95% confidence interval [CI] 1.1-7.1; P = .048) and acute mesenteric ischemia/infarction (OR = 6.9; 95% CI 2.5-20; P < .001). Adjusting for patient characteristics, ALI was associated with death (3.5; 95% CI 1.1-10; P = .02). The single institution analysis revealed similar patient demographics and mortality in 93 AoD patients, of whom 28 had ALI. Aortic fenestration or aorto-iliac stenting was the primary therapy in 93%; surgical bypass was used in 7%. Limb salvage was 93% in those with ALI at a mean of 18 months follow-up. The number of organ systems with malperfusion was 2-fold higher at aortography than suspected preprocedure (P = .002). By stepwise regression modeling, mortality was greater in those not taking a beta-blocker (OR = 19; 95% CI 3.1-111; P = .001). CONCLUSIONS: ALI secondary to AoD is predictive of death and visceral ischemia. Endovascular therapy confers excellent limb salvage and allows diagnosis of unsuspected visceral ischemia.

Acute Disease↗
PubMed2001

A new concept for multidimensional selection of ligand conformations (MultiSelect) and multidimensional scoring (MultiScore) of protein-ligand binding affinities.

In this work, eight different scoring functions have been combined with the aim of improving the prediction of protein-ligand binding conformations and affinities. The obtained scores were analyzed using multivariate statistical methods to generate expressions, with the ability (1) to select the best candidate between different docked conformations of an inhibitor (MultiSelect) and (2) to quantify the protein-ligand binding affinity (MultiScore). By use of the docking program GOLD, 40 different inhibitors were docked into the active site of three matrix metalloproteinases (MMP's), yielding a total of 120 enzyme-inhibitor complexes. For each complex, a single conformation of the inhibitor was selected using principal component analysis (PCA) for the scores obtained by the eight functions SCORE, LUDI, GRID, PMF_Score, D_Score, G_Score, ChemScore, and F_Score. Binding affinities were estimated based on partial least-squares projections onto latent structures (PLS) on the eight scores of each selected inhibitor conformation. By use of this procedure, R(2) = 0.78 and Q(2) = 0.78 were obtained when comparing experimental and calculated binding affinities. MultiSelect was evaluated by applying the same method for selecting docked conformations for 18 different protein-ligand complexes of known three-dimensional structure. In all cases, the selected ligand conformations were found to be very similar to the experimentally determined ligand conformations. A more general evaluation of MultiScore was performed using a set of 120 different protein-ligand complexes for which both the three-dimensional structures and the binding affinities were known. This approach allowed an evaluation of MultiScore independently of MultiSelect. The generality of the method was verified by obtaining R(2) = 0.68 and Q(2) = 0.67, when comparing calculated and experimental binding affinities for the 120 X-ray structures. In all cases, LUDI, SCORE, GRID, and F_Score were included as important functions, whereas the fifth function was PMF_Score and ChemScore for the MMP and X-ray models, respectively.

Crystallography, X-Ray↗
PubMed2000

Hepato-venous reconstruction in orthotopic liver transplantation with preservation of the recipients' inferior vena cava and veno-venous bypass.

BACKGROUND AND AIMS: The potential advantages of vena cava-preserving recipient hepatectomy in orthotopic liver transplantation are reduced hemorrhage, improved cardiovascular stability and preserved renal perfusion without the requirement of veno-venous bypass as compared with recipient hepatectomy including the vena cava. No detailed information is available on the use of veno-venous bypass during complicated vena cava preserving recipient hepatectomy and liver transplantation. In the present study, the peri- and postoperative courses of adult liver transplant recipients in whom the hepatovenous reconstruction was performed according to three different techniques with and without the use of veno-venous bypass were investigated. PATIENTS/METHODS: During primary orthotopic liver transplantation, an end-to-end (ETE) cavo-caval interposition of the donor vena cava to the recipient's vena cava was performed in 75 patients (group I). In 15 patients, a termino-terminal piggyback (PB) anastomosis was constructed to the remnant of the recipient's hepatic vein (group II), and in 72 transplantations a latero-lateral cavo-cavostomy (LLC) of donor-to-recipient's vena cava (group III) was performed. The use of bypass, operative time and cold ischemia time, perioperative blood product requirements, incidence of relaparotomy, the evolution of postoperative renal function, technical complications and the survival were analyzed and compared using multivariate statistics and actuarial techniques for statistical evaluation. RESULTS: No differences could be found in preoperative patient conditions, donor conditions, operating time, anastomosing time or cold ischemia time. In groups I-III, the veno-venous bypass was used in 50 (67%), 8 (53%) and 6 (8%) cases respectively (P=0.02 for group III). The mean preoperative packed cells requirements were 20.4 vs 29.6 vs 10.8 units (P=0.01 for group III), while postoperative blood product requirements (first 24 h) were 2.6 vs 5.0 vs 0.20 units of packed cells (P=0.02 for group III). Relaparotomy for diffuse retroperitoneal hemorrhage was performed 14 times (19%) in group I, 3 times (20%) in group II and 7 times (8.3%) in group III (P=0.002). The incidence of posteropative early renal dysfunction (increase of > or =1.3 mg% serum creatinine) in group I vs group II vs group III was 24% vs 60% vs 16.7% (P=0.001 for group II) for patients without the use of veno-venous bypass. No significant difference was observed concerning early renal dysfunction in patients where a veno-venous bypass was used. The survival at 12 months was 81% for group I, 86% for group II and 93.0% for group III. In group III there were four complications (P=0.03) at the hepatovenous anastomosis of which two were eventually fatal. CONCLUSION: Preservation of the recipient's vena cava and LLC can reduce, but not avoid, the requirement for veno-venous bypass. In orthotopic liver transplantation, postoperative hemorrhage, as measured by surgical revisions and requirement for blood products, is significantly reduced with LLC with and without bypass. Early renal dysfunction also occurs in the group of LLC as compared with the termino-terminal cavostomy independent of the bypass. A technical failure resulting in patient death can be associated with LLC.

Adult↗
PubMed1998

Operative outcome and hospital cost.

INTRODUCTION: Because of concern about increasing health care costs, we undertook a study to find patient risk factors associated with increased hospital costs and to evaluate the relationship between increased cost and in-hospital mortality and serious morbidity. METHODS: More than 100 patient variables were screened in 1221 patients undergoing cardiac procedures. Simultaneously, patient hospital costs were computed from the cost-to-charge ratio. Univariate and multivariate statistics were used to explore the relationship between hospital cost and patient outcomes, including operative death, in-hospital morbidity, and length of stay. RESULTS: The greatest costs were for 31 patients who did not survive operation ($74,466, 95% confidence interval $27,102 to $198,025), greater than the costs for 120 patients who had serious, nonfatal morbidity ($60,335, 95% confidence interval $28,381 to $130,897, p = 0.02) and those for 1070 patients who survived operation without complication ($31,459, 95% confidence interval $21,944 to $49,849, p = 0.001). Breakdown of the components of hospital costs in fatalities and in cases with nonfatal complications revealed that the greatest contributions were in anesthesia and operating room costs. Significant (by stepwise linear regression analysis) independent risks for increased hospital cost were as follows (in order of decreasing importance): (1) preoperative congestive heart failure, (2) serum creatinine level greater than 2.5 mg/dl, (3) New York state predicted mortality risk, (4), type of operation (coronary artery bypass grafting, valve, valve plus coronary artery bypass grafting, or other), (5) preoperative hematocrit, (6) need for reoperative procedure, (7) operative priority, and (8) sex. These risks were different than those for in-hospitality death or increased length of stay. Hospital cost correlated with length of stay (r = 0.63, p < 0.001), but there were many outliers at the high end of the hospital cost spectrum. CONCLUSIONS: We conclude that operative death is the most costly outcome; length of stay is an unreliable indicator of hospital cost, especially at the high end of the cost spectrum; risks of increased hospital cost are different than those for perioperative mortality or increased length of stay; and ventricular dysfunction in elderly patients undergoing urgent operations for other than coronary disease is associated with increased cost. Certain patient factors, such as preoperative anemia and congestive heart failure, are amenable to preoperative intervention to reduce costs, and a high-risk patient profile can serve as a target for cost-reduction strategies.

Cardiac Surgical Procedures↗
PubMed2004

The cost-effectiveness of independent housing for the chronically mentally ill: do housing and neighborhood features matter?

OBJECTIVE: To determine the effects of housing and neighborhood features on residential instability and the costs of mental health services for individuals with chronic mental illness (CMI). DATA SOURCES: Medicaid and service provider data on the mental health service utilization of 670 individuals with CMI between 1988 and 1993 were combined with primary data on housing attributes and costs, as well as census data on neighborhood characteristics. Study participants were living in independent housing units developed under the Robert Wood Johnson Foundation Program on Chronic Mental Illness in four of nine demonstration cities between 1988 and 1993. STUDY DESIGN: Participants were assigned on a first-come, first-served basis to housing units as they became available for occupancy after renovation by the housing providers. Multivariate statistical models are used to examine the relationship between features of the residential environment and three outcomes that were measured during the participant's occupancy in a study property: residential instability, community-based service costs, and hospital-based service costs. To assess cost-effectiveness, the mental health care cost savings associated with some residential features are compared with the cost of providing housing with these features. DATA COLLECTION/EXTRACTION METHODS: Health service utilization data were obtained from Medicaid and from state and local departments of mental health. Non-mental-health services, substance abuse services, and pharmaceuticals were screened out. PRINCIPAL FINDINGS: Study participants living in newer and properly maintained buildings had lower mental health care costs and residential instability. Buildings with a richer set of amenity features, neighborhoods with no outward signs of physical deterioration, and neighborhoods with newer housing stock were also associated with reduced mental health care costs. Study participants were more residentially stable in buildings with fewer units and where a greater proportion of tenants were other individuals with CMI. Mental health care costs and residential instability tend to be reduced in neighborhoods with many nonresidential land uses and a higher proportion of renters. Mixed-race neighborhoods are associated with reduced probability of mental health hospitalization, but they also are associated with much higher hospitalization costs if hospitalized. The degree of income mixing in the neighborhood has no effect. CONCLUSIONS: Several of the key findings are consistent with theoretical expectations that higher-quality housing and neighborhoods lead to better mental health outcomes among individuals with CMI. The mental health care cost savings associated with these favorable features far outweigh the costs of developing and operating properties with them. Support for the hypothesis that "diverse-disorganized" neighborhoods are more accepting of individuals with CMI and, hence, associated with better mental health outcomes, is mixed.

Activities of Daily Living↗
PubMed2001

Hepatitis B and C virus infection in Crohn's disease.

Patients with Crohn's disease (CD) are at higher risk of hepatitis C (HCV) and B virus (HBV) infection, because of surgical and/or endoscopic procedures. However, the prevalence of HCV and HBV infection in CD is unknown. This issue may be relevant because of the growing use of immunomodulatory drugs in CD. The purpose of this study was to assess, in a multicenter study, the prevalence and risk factors of HCV and HBV infection in CD. The effect of immunomodulatory drugs for CD on the clinical course of hepatitis virus infections and of interferon-alpha (IFN-alpha) on the course of CD was examined in a small number of patients. Sera from 332 patients with CD and 374 control subjects (C) were tested for the following: hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb), HBcAb, HBeAg, HBeAb, anti-HCV, and HCV-RNA. An additional 162 patients with ulcerative colitis (UC) were tested as a disease control group. Risk factors were assessed by multivariate statistical analysis. Infection by either HCV or HBV was detected in 24.7% of patients with CD. In the age groups younger than 50 years, HCV prevalence was higher in CD than in C (p = 0.01). HCV infection in CD was associated with surgery (OR 1.71; 95% CI 1.00-2.93; p = 0.04), blood transfusions (OR 3.39; 95% CI 1.04-11.04; p = 0.04), and age (OR 2.3; 95% CI 1.61-3.56; p < 0.001). The event CD-related surgery appeared to be the main risk factor for HCV infection in CD. HCV prevalence was higher in CD (7.4%) than in UC (0.6%) (p = 0.001). HBcAb positivity was higher in CD (10.9%) and UC (11.5%) than in C (5.1%) (CD vs. C: p = 0.016; UC vs. C: p = 0.02), associated with age (OR 2.08; 95% CI 1.37-3.17; p = 0.001) and female gender (OR 2.68; 95% CI 1.37-3.17; p = 0.001) in CD and to UC duration (OR 1.20; 95% CI 1.06-1.36; p = 0.002). Immunomodulatory drugs did not influence the course of HBV or HCV infection in seven patients with CD, and IFN-alpha for chronic hepatitis C did not affect CD activity in six patients with CD. It is concluded that HBV prevalence is higher in CD than in C at all ages, whereas HCV prevalence is increased in young patients with CD, because of a greater need for surgery. The higher HCV (but not HBV) prevalence in CD than in UC suggests that the host immune response may influence the risk of HCV infection. Although a relatively high proportion of patients with CD showed HBV and/or HCV infections, this should not influence treatment strategies for CD.

Adolescent↗
PubMed2000

Risk factors for morbidity and mortality after colectomy for colon cancer.

PURPOSE: Comorbid conditions affect the risk of adverse outcomes after surgery, but the magnitude of risk has not previously been quantified using multivariate statistical methods and prospectively collected data. Identifying factors that predict results of surgical procedures would be valuable in assessing the quality of surgical care. This study was performed to define risk factors that predict adverse events after colectomy for cancer in Department of Veterans Affairs Medical Centers. METHODS: The National Veterans Affairs Surgical Quality Improvement Program contains prospectively collected and extensively validated data on more than 415,000 surgical operations. All patients undergoing colectomy for colon cancer from 1991 to 1995 who were registered in the National Veterans Affairs Surgical Quality Improvement Program database were selected for study. Independent variables examined included 68 preoperative and 12 intraoperative clinical risk factors; dependent variables were 21 specific adverse outcomes. Stepwise logistic regression analysis was used to construct models predicting the 30-day mortality rate and 30-day morbidity rates for each of the ten most frequent complications. RESULTS: A total of 5,853 patients were identified; 4,711 (80 percent) underwent resection and primary anastomosis. One or more complications were observed in 1,639 of 5,853 (28 percent) patients. Prolonged ileus (439/5,853; 7.5 percent), pneumonia (364/5,853; 6.2 percent), failure to wean from the ventilator (334/5,853; 5.7 percent), and urinary tract infection (292/5,853; 5 percent) were the most frequent complications. The 30-day mortality rate was 5.7 percent (335/5,853). For most complications, 30-day in-hospital mortality rates were significantly higher for patients with a complication than for those without. Thirty-day mortality rates exceeded 50 percent if postoperative coma, cardiac arrest, a pre-existing vascular graft prosthesis that failed after colectomy, renal failure, pulmonary embolism, or progressive renal insufficiency occurred. Preoperative factors that predicted a high risk of 30-day mortality included ascites, serum sodium >145 mg/dl, "do not resuscitate" status before surgery, American Society of Anesthesiologists classes III and IV OR V, and low serum albumin. CONCLUSIONS: Mortality rates after colectomy in Veterans Affairs hospitals are comparable with those reported in other large studies. Ascites, hypernatremia, do not resuscitate status before surgery, and American Society of Anesthesiologists classes III and IV OR V were strongly predictive of perioperative death. Clinical trials to decrease the complication rate after colectomy for colon cancer should focus on these risk factors.

Adult↗
PubMed2001

Multivariate patterns of biochemical responses of Pinus ponderosa trees at field plots in the San Bernardino Mountains, southern California.

Most environmental stress conditions promote the production of potentially toxic active oxygen species in plant cells. Plants respond with changes in their antioxidant and photoprotective systems. Antioxidants and pigments have been widely used to measure these responses. Because trees are exposed to multiple man-made and natural stresses, their responses are not reflected by changes in single stress markers, but by complex biochemical changes. To evaluate such response patterns, explorative multivariate statistics have been used. In the present study, 12 biochemical variables (chloroplast pigments, state of the xanthophyll cycle, alpha-tocopherol, ascorbate and dehydroascorbate, glutathione and oxidized glutathione) were measured in previous-year needles of field-grown Pinus ponderosa Dougl. ex Laws. The trees were sampled in two consecutive years in the San Bernardino Mountains in southern California, where a pollution gradient is overlaid by gradients in natural stresses (drought, altitude). To explore irradiance effects, needle samples were taken directly in the field (sun exposed) and from detached, dark-adapted branches. A principal component analysis on this data set (n = 80) resulted in four components (Components 1-4) that explained 67% of the variance in the original data. Component 1 was positively loaded by concentrations of alpha-tocopherol, total ascorbate and xanthophyll cycle pools, as well as by the proportion of de-epoxides in the xanthophyll cycle. It was negatively loaded by the proportion of dehydroascorbate in the ascorbate pool. Component 2 was negatively loaded by chlorophyll concentrations, and positively loaded by the ratios of lutein and beta-carotene to chlorophyll and by the de-epoxidation state of the xanthophyll cycle. Component 3 was negatively loaded by GSH concentrations and positively loaded by the proportions of GSSG and tocopherol concentrations. Component 4 was positively loaded by neoxanthin and negatively loaded by beta-carotene. The four components could be assigned to the concerted action of the biochemical protection system: high scores on Component 1 represent highly activated antioxidative defense, changes in pigment composition are represented in Components 2 and 4, and the glutathione system, which is important for antioxidant regeneration, is represented in Component 2. Although Component 1 scores were generally higher (indicating activation of antioxidant defense) in light-adapted needles relative to dark-adapted needles, they were also site dependent with increased scores at sites with less pollution, but higher natural stress impacts. High scores of Components 2 and 3 at the highest elevation site, which was only moderately polluted, indicated an increase in photoprotection by pigments and activation of the glutathione system. Significant differences between light- and dark-adapted needles in Components 2 and 3 were only found at the site with the highest pollution. Use of accumulated variables (components) instead of single biochemical variables enabled recognition of response patterns at particular sites and a better comparison with results of other studies is expected. Typical response patterns could be assigned to particular environmental stress combinations, providing a means of assessing potential biological risks within individual forest stands.

Air Pollution↗
PubMed1991

Identification of first acute Q wave and non-Q wave myocardial infarction by multivariate analysis of body surface potential maps.

BACKGROUND: Patients with acute non-Q wave myocardial infarction (NQMI) appear to have more jeopardized residual myocardium at high risk for subsequent angina, reinfarction, or malignant arrhythmias than patients with acute Q wave myocardial infarction (QMI). Unfortunately, conventional electrocardiographic (ECG) criteria have limited utility in recognizing NQMI. METHODS AND RESULTS: The present study combines the increased information content of body surface potential maps (BSPM) over the 12-lead ECG with the power of multivariate statistical procedures to identify a practical subset of leads that would allow improved diagnosis of NQMI. Discriminant analysis was performed on 120-lead data recorded simultaneously in 159 normal subjects and 308 patients with various types of myocardial infarction (MI) by using instantaneous voltages on time-normalized P, PR, QRS, and ST-T waveforms as well as the duration of these waveforms as features. Leads and features for optimal separation of 159 normals from 183 patients with recent or old QMI (group A) were selected. A total of six features from six torso sites accounted for a specificity of 96% and a sensitivity of 94%. All lead positions were outside the conventional electrode sites and selected features were voltages at mid-P, early and mid-QRS, and before and after the peak of the T wave. The discriminant function was then tested on 57 patients with acute NQMI (group B) and 68 patients with acute QMI (group C): Rates of correct classification were 91% and 93%, respectively. Because of the possible deterioration of the results caused by ST-T abnormalities also present in other clinical entities, a second classification model including an independent group of 116 patients with left ventricular hypertrophy (LVH) but without MI was developed. Two additional measurements were required, namely, P wave duration and a mid-QRS voltage on a lead located 10 cm below V1. Testing the model on both acute MI groups produced correct classification rates of 88% for acute NQMI and 93% for acute QMI. Group mean BSPM were plotted for the three MI groups at successive instants throughout the PQRST waveform. Typical patterns for each MI group were identified during PQRST by removing the corresponding normal variability at each electrode site from sequential MI maps. These standardized maps or discriminant maps provided information on the capability of each measurement at each electrode site and at each instant to separate each class of MI from the normal group (N). Striking similarities were observed between the three MI groups, particularly at mid-QRS and throughout ST-T. The closest resemblance was between acute NQMI and old QMI. Discriminant analysis was also performed on the 12-lead ECG: The first classification model (N versus MI) produced correct classification rates of 85% for acute QMI and 70% for NQMI. With the second model (MI versus N or LVH), correct rates were 81% and 65%, respectively. CONCLUSIONS: Diagnosis of acute NQMI and QMI (also in the presence of LVH) can be improved substantially by appropriate selection of ECG leads and features. Comparison of discriminant maps from groups A, B, and C does not support the concept of acute NQMI as a distinct ECG entity but rather as a group with infarcts of smaller size. However, pathophysiological and clinical differences between acute NQMI and acute QMI influence long-term risks and may define different therapeutic approaches.

Adult↗
PubMed1999

A community-based study of chronic fatigue syndrome.

BACKGROUND: Most previous estimates of the prevalence of chronic fatigue syndrome (CFS) have derived largely from treated populations, and have been biased by differential access to health care treatment linked with sex, ethnic identification, and socioeconomic status. OBJECTIVE: To assess the point prevalence of CFS in an ethnically diverse random community sample. DESIGN AND PARTICIPANTS: A sample of 28,673 adults in Chicago, Ill, was screened by telephone, and those with CFS-like symptoms were medically evaluated. MAIN OUTCOME MEASURES AND ANALYSES: Self-report questionnaires, psychiatric evaluations, and complete medical examinations with laboratory testing were used to diagnose patients with CFS. Univariate and multivariate statistical techniques were used to delineate the overall rate of CFS in this population, and its relative prevalence was subcategorized by sex, ethnic identification, age, and socioeconomic status. RESULTS: There was a 65.1% completion rate for the telephone interviews during the first phase of the study. Findings indicated that CFS occurs in about 0.42% (95% confidence interval, 0.29%-0.56%) of this random community-based sample. The highest levels of CFS were consistently found among women, minority groups, and persons with lower levels of education and occupational status. CONCLUSIONS: Chronic fatigue syndrome is a common chronic health condition, especially for women, occurring across ethnic groups. Earlier findings suggesting that CFS is a syndrome primarily affecting white, middle-class patients were not supported by our findings.

Adult↗
PubMed1989

Regional distribution of cerebral arteriovenous malformations. Interactions with sex and handedness.

On the basis of clinical observation and a developmental theory of cerebral laterality, Geschwind and Galaburda suggested that cerebral arteriovenous malformations (AVMs) are more common in the left hemispheres of male patients. We tested this hypothesis by examining interactions among sex, handedness, and location of lateralized, supratentorial AVMs. Data from 112 cases were analyzed by log-linear procedures. We found that (1) females had a greater proportion of left-hemisphere AVMs, whereas males showed an opposite trend; (2) there were no interactions between sex and handedness; and (3) nondextrals showed a higher proportion of AVMs located in frontal regions, regardless of the hemispheric side of the lesion. Although these findings appear to be inconsistent with the Geschwind-Galaburda hypothesis, the inconsistency may be attributable to the embryonic stage at which this developmental abnormality occurs. In addition, the unexpected findings may also reflect our use of multivariate statistical procedures, which control for interaction effects.

Adolescent↗
PubMed1995

Changes in survival patterns of very low-birth-weight infants from 1980 to 1993.

OBJECTIVE: To determine changes in survival patterns among very low-birth-weight ( < 1500 g) infants between 1980 and 1993. METHODS: The records of 12,960 infants treated in nine perinatal intensive care centers in Florida were analyzed on the basis of survival (discharged alive from hospital) according to four independent variables: birth weight, race, sex, and transport status. Survival curves were generated using log linear regression techniques for each race by sex by transport status group. RESULTS: Race, sex, and transport status correlated significantly with survival: survival percentages were higher among black infants, female infants, and infants transported to the perinatal intensive care centers than among white infants, male infants, and those admitted initially to the tertiary care centers. After 1985, 95% of neonates with birth weights between 1200 and 1500 g survived. In addition, survival of 500- to 500-g transported black male infants increased from zero to near 80% during the 13-year period; that of 500- to 550-g inborn white female infants rose from 35% to 70%. CONCLUSIONS: These results illustrate the value of taking into account race, sex, and transport status in efforts to understand the contribution that neonatal intensive care of extremely low-birth-weight infants makes to the lowering of infant mortality, and of using multivariable statistical procedures to generate predicted survival probabilities for different subpopulations. These probabilities can be applied to (1) predicting survival for specific subgroups of extremely low-birth-weight infants, and (2) helping physicians develop clinical guidelines for extending care to infants at the threshold of viability.

Birth Weight↗
PubMed1997

Hospital infant formula discharge packages. Do they affect the duration of breast-feeding?

OBJECTIVE: To determine whether the duration of breast-feeding is affected by the contents of the hospital discharge package. DESIGN: A randomized clinical trial with 2 experimental interventions (a discharge package containing a manual breast pump only and a discharge package containing a commercially prepared infant formula and a manual breast pump) and a control group who received a commercially prepared infant formula discharge package only. Sociodemographic characteristics and information concerning prior births (including feeding methods) were obtained from each mother within 48 hours of her infant's birth. Sources of influence on the mother's feeding decision, maternal attitudes concerning breast-feeding, and maternal feeding preferences were also assessed. PARTICIPANTS: The sample consisted of 763 women who had given birth who were admitted to the maternal-fetal unit of a midwestern community hospital. MAIN OUTCOME MEASURES: Information concerning current method of infant feeding was obtained from telephone interviews conducted at 2-week intervals until the infant was 16 weeks old. The data were analyzed using descriptive statistics, multivariate analysis of variance, logistic regression analysis, and survival analysis. RESULTS: The content of the hospital discharge package did not affect whether the mother engaged in exclusive or partial breast-feeding during the 16-week follow-up interval. However, there was some evidence that providing formula samples at discharge from the hospital increased the duration of exclusive breast-feeding compared with providing a manual breast pump. CONCLUSION: This study does not support the assumption that inclusion of infant formula in hospital discharge packages decreases the duration of breast-feeding.

Adult↗
PubMed1981

The alcoholic family at home. Patterns of interaction in dry, wet, and transitional stages of alcoholism.

Thirty-one alcoholic families were observed in their homes on nine separate occasions over a six-month period. During each occasion, behavioral observers made systematic recordings of interactional behavior using the Home Observation Assessment Method, a method that concentrates on the family's style of regulating its home environment. Three distinct patterns of home behavior could be identified using univariate and multivariate statistical analyses. Each pattern was associated dry, or transitional phase. This suggests that these families manifest characteristic family-level patterns of behavior in their homes at different stages in the course of chronic alcoholism. The critical issue was the relative rigidity vs flexibility of behavior. Families in either stable wet and transitional phases proved to have rigid patterns of behavior; those in the stable dry phase had flexible patterns. The findings provide an initial insight into how families manage a chronic disease process in their home environment.

Adult↗
PubMed1982

Tardive dyskinesia in psychiatric outpatients: a study of prevalence and association with demographic, clinical, and drug history variables.

We examined 153 psychiatric outpatients, on a maintenance regimen of neuroleptics, for tardive dyskinesia (TD) and parkinsonism. Demographic, clinical, and drug history data were collected to assess whether any of these factors were significantly associated with TD. After initial univariate screening, significant variables were analyzed by multivariate statistical methods. Tardive dyskinesia was significantly associated with the use of high-potency or high-dosage neuroleptics and depot fluphenazine, whereas low-potency neuroleptics were negatively correlated with moderate TD. Age, but not sex, correlated significantly with TD, as did histories of incoherence, grandiose delusions, and teeth or denture problems. Parkinsonism and TD were strongly associated. Although the prevalence of TD was quite high, there were no severe involvements of any of the Abnormal Involuntary Movement Scale body areas.

Age Factors↗
PubMed1984

Biological 'markers' for endogenous depression. Effect of age, severity of illness, weight loss, and polarity.

The dexamethasone suppression test (DST) can differentiate between endogenous and nonendogenous depression. Similarly, EEG sleep patterns can differentiate primary from secondary depression, and this technique has also been used to make the endogenous-nonendogenous discrimination. However, a number of physiological variables associated with this diagnostic distinction may also affect the DST results and sleep architecture. With the use of multivariate statistical procedures, we found that although age and weight loss affect the results of both tests, both the DST and sleep EEG differentiate endogenous from nonendogenous depression when these variables are taken into account. Severity of illness affected both proposed diagnostic markers, but did not account for the differences between diagnostic groups, alone or when added to the physiological variables. The DST was more sensitive in unipolar than in bipolar endogenous depression, but there were no significant differences in the sleep of unipolar and bipolar patients.

Adult↗
PubMed1998

Liver transplantation for fulminant hepatic failure in the pediatric patient.

OBJECTIVE: To review the clinical characteristics, outcomes, and risk factors for survival among 57 pediatric patients undergoing orthotopic liver transplantation for fulminant hepatic failure at the University of California, Los Angeles, Center for the Health Sciences. DESIGN: The medical records of 57 consecutive pediatric patients undergoing orthotopic liver transplantation for fulminant hepatic failure from July 1, 1984, to June 25, 1997, were reviewed and survival data were analyzed via univariate and multivariate statistical methods. The type and incidence of posttransplant complications were determined as was the quality of long-term graft function. Median follow-up period was 3.38 years (range, 0-10.02 years). RESULTS: The 1-, 3-, and 5-year actuarial patient survival rates were 77%, 77%, and 77%, respectively, while graft survivals were 73%, 65%, and 65%. Stepwise Cox regression analysis revealed that recipient age and ventilator dependency at the time of transplantation were independently and significantly correlated with patient survival, whereas no association was found between survival and grade of encephalopathy, prior abdominal surgery, recipient weight, pretransplantation values for total bilirubin or prothrombin time, ABO match, allograft type, peak posttransplantation aspartate aminotransferase levels, or the presence of posttransplantation hepatic artery thrombosis. Non-ventilator-dependent patients demonstrated a 96% 1-, 3-, and 5-year survival as compared with only 56% at these same time points for those children requiring ventilator support at the time of transplantation (P < .001). At the time of most recent follow-up, median values for total bilirubin and aspartate aminotransferase concentrations were 10.3 micromol/L (0.6 mg/dL) and 56 U/L, respectively, in the 40 surviving patients. CONCLUSIONS: In children undergoing liver transplantation for fulminant hepatic failure: (1) overall results are comparable to those achieved for less emergent non-neoplastic indications in this same age group; (2) ventilator dependency prior to transplantation is the strongest predictor of ultimate survival, followed by recipient age; (3) 5-year survival exceeds 90% in recipients who are ventilator independent immediately prior to liver transplantation but is significantly compromised once the need for mechanical ventilation supervenes, particularly in those younger than 4 years; and (4) prompt referral and timely liver replacement are the cornerstones of optimal outcome.

Actuarial Analysis↗