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PubMed1990

Differences in knowledge of and risk factors for AIDS between Hispanic and non-Hispanic women attending an urban family planning clinic.

Risk factors for AIDS, contraceptive use, seroprevalence of HIV, and level of knowledge before and after an AIDS education session were assessed for 657 clients attending a family planning clinic in Los Angeles, USA. History of a partner who was bisexual, an intravenous drug user, or a blood transfusion recipient were the most common risk factors. Spanish speakers reported fewer traditional risk factors than English speakers. They were also less likely to report a history of drug or alcohol use or sexually transmitted diseases, and to have had fewer sexual partners. Less than one-third of the women identified as being at risk of exposure were using condoms. None of 351 consecutive patients tested for HIV antibodies was positive. English speakers scored higher on both pre- and post-tests of knowledge about AIDS. Cultural factors may lower the personal risk of HIV exposure for Spanish-speaking women, but lack of knowledge about AIDS and partner behavior may increase risk.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Quantification of neuroreceptors in the living human brain: III. D2-like dopamine receptors: theory, validation, and changes during normal aging.

Dopamine receptor density is believed to decline in normal aging. To test this hypothesis, we measured the density of dopamine D2-like receptors in vivo in the neostriatum of normal living humans by using the graphical method. This method determines the D2-like dopamine receptor density in the human brain with an occupying ligand (unlabeled haloperidol) and a radioligand (labeled 3-N-methylspiperone). The method was examined critically, and the assumptions underlying the method were shown to be valid. The validation included comparison of the representation of tracer metabolism by high-pressure liquid chromatography and model assays, calculation of the lumped constant Dw from the value of its components, and comparable tracer partition coefficients in vitro and in vivo. In error analysis, the method consistently performed as well as the direct least-squares regression at statistical noise levels appropriate for the tomograph used in these studies. The method revealed that the density of the D2-like receptors that bind haloperidol in the caudate nucleus of normal humans declined 1% per year after the age of 18 years.

Aging↗
PubMed2000

High-normal serum homocysteine concentrations are associated with an increased risk of early atherosclerotic carotid artery wall lesions in healthy subjects.

OBJECTIVE: Moderate hyperhomocysteinaemia is common in the general population and has been linked with systemic atherosclerotic vascular disease. We studied the relation of sonographically determined carotid intima-media wall thickness to serum homocysteine concentrations in asymptomatic, healthy subjects. METHODS AND RESULTS: Seventy-five male and female untreated subjects (mean age 49 years, range 22-75) with normal serum folate concentrations were included. High-resolution duplex sonography was used to determine intima-media thickness of the common carotid artery. Serum homocysteine concentration was measured by high-performance liquid chromotography with fluorescence detection. Mean intima-media thickness (+/- SD) was 0.78 +/- 0.19 mm (range 0.5-1.35) and mean serum homocysteine concentration was 10.5 +/- 2.81 micromol/l (range 5.7-19.6). In stepwise regression models, statistically significant predictors of intima-media thickness included age, body mass index, LDL cholesterol and homocysteine (R2 = 0.51). Homocysteine concentration was independently associated with intima-media thickness after adjustment for the other variables (P < 0.001) and explained an additional 18% of the variation of intima-media thickness. CONCLUSIONS: In healthy subjects, high-normal serum homocysteine concentrations are associated with an increased prevalence of carotid artery wall thickening. The significance of the contribution of homocysteine to the variation of carotid intima-media thickness, even at concentrations previously believed to be normal, suggests a role for homocysteine as an independent risk factor for early carotid artery atherosclerosis in the asymptomatic subjects.

Adult↗
PubMed1996

The relationship of oxygen consumption measured by indirect calorimetry to oxygen delivery in critically ill patients.

OBJECTIVE: The existence of oxygen supply dependency, defined as oxygen consumption (VO2) limited by oxygen delivery (DO2), is still questioned. This study examined the relationship between VO2 and DO2 in two groups of critically ill surgical patients 50 years and older in the first 24 hours of resuscitation after pulmonary artery catheter insertion. Group 1 patients had systemic inflammatory response syndrome (SIRS), sepsis, severe sepsis, septic shock, and adult respiratory distress syndrome (ARDS). Group 2 patients had hemorrhagic shock. METHODOLOGY: Study methodology included (1) augmenting DO2 with fluids, blood, and vasopressors, (2) measuring VO2 by indirect calorimetry to avoid the problem of mathematical coupling with DO2 calculation, and (3) analyzing data during steady states of temperature, sedation, paralyzing agents, and vasopressors. RESULTS: Six to 18 measurements collected on all study patients during a period within the first 24 hours were analyzed using a linear regression analysis. Statistical significance was set at p < or = 0.05. Seven of nine patients in group 1 demonstrated positive, statistically significant relationships between VO2 and DO2. Of six patients in group 2, one patient demonstrated a positive, significant relationship of VO2 and DO2, three demonstrated inverse relationships, and two patients did not show a DO2/VO2 relationship. Supply dependency did not exist in all patients but was present in seven out of nine patients with systemic inflammatory response syndrome, sepsis, severe sepsis, septic shock, and adult respiratory distress syndrome in the first 24 hours of treatment.

Aged↗
PubMed1998

A new casemix adjustment index for hospital mortality among patients with congestive heart failure.

OBJECTIVES: Comparative analysis of hospital outcomes requires reliable adjustment for casemix. Although congestive heart failure is one of the most common indications for hospitalization, congestive heart failure casemix adjustment has not been widely studied. The purposes of this study were (1) to describe and validate a new congestive heart failure-specific casemix adjustment index to predict in-hospital mortality and (2) to compare its performance to the Charlson comorbidity index. METHODS: Data from all 4,608 admissions to the Massachusetts General Hospital from January 1990 to July 1996 with a principal ICD-9-CM discharge diagnosis of congestive heart failure were evaluated. Massachusetts General Hospital patients were randomly divided in a derivation and a validation set. By logistic regression, odds ratios for in-hospital death were computed and weights were assigned to construct a new predictive index in the derivation set. The performance of the index was tested in an internal Massachusetts General Hospital validation set and in a non-Massachusetts General Hospital external validation set incorporating data from all 1995 New York state hospital discharges with a primary discharge diagnosis of congestive heart failure. RESULTS: Overall in-hospital mortality was 6.4%. Based on the new index, patients were assigned to six categories with incrementally increasing hospital mortality rates ranging from 0.5% to 31%. By logistic regression, "c" statistics of the congestive heart failure-specific index (0.83 and 0.78, derivation and validation set) were significantly superior to the Charlson index (0.66). Similar incrementally increasing hospital mortality rates were observed in the New York database with the congestive heart failure-specific index ("c" statistics 0.75). CONCLUSION: In an administrative database, this congestive heart failure-specific index may be a more adequate casemix adjustment tool to predict hospital mortality in patients hospitalized for congestive heart failure.

Aged↗
PubMed2001

Evaluating diagnosis-based case-mix measures: how well do they apply to the VA population?

BACKGROUND: Diagnosis-based case-mix measures are increasingly used for provider profiling, resource allocation, and capitation rate setting. Measures developed in one setting may not adequately capture the disease burden in other settings. OBJECTIVES: To examine the feasibility of adapting two such measures, Adjusted Clinical Groups (ACGs) and Diagnostic Cost Groups (DCGs), to the Department of Veterans Affairs (VA) population. RESEARCH DESIGN: A 60% random sample of veterans who used health care services during FY 1997 was obtained from VA inpatient and outpatient administrative databases. A split-sample technique was used to obtain a 40% sample (n = 1,046,803) for development and a 20% sample (n = 524,461) for validation. METHODS: Concurrent ACG and DCG risk adjustment models, using 1997 diagnoses and demographics to predict FY 1997 utilization (ambulatory provider encounters, and service days-the sum of a patient's inpatient and outpatient visit days), were fitted and cross-validated. RESULTS: Patients were classified into groupings that indicated a population with multiple psychiatric and medical diseases. Model R-squares explained between 6% and 32% of the variation in service utilization. Although reparameterized models did better in predicting utilization than models with external weights, none of the models was adequate in characterizing the entire population. For predicting service days, DCGs were superior to ACGs in most categories, whereas ACGs did better at discriminating among veterans who had the lowest utilization. CONCLUSIONS: Although "off-the-shelf" case-mix measures perform moderately well when applied to another setting, modifications may be required to accurately characterize a population's disease burden with respect to the resource needs of all patients.

Aged↗
PubMed1980

Type A behavior and blood pressure during coronary artery bypass surgery.

Systemic hypertension has been reported as common during coronary artery bypass surgery. The coronary-prone Type A behavior pattern has been associated with heightened reactivity of the sympathetic nervous system. Therefore, the possible relationships between the two was explored. Significant correlations were found between systolic blood pressure rise during surgery and interview ratings of overall Type A (p < 0.05), aggressive content (p < 0.01), and job commitment (p < 0.001). A statistically association was also found between diastolic pressure rise and the job commitment rating (p < 0.01). Significant correlations were still present after controlling for the role of physical predictors of blood pressure rise by statistical multiple regression analysis. The data suggest that patients with Type A behavior characteristics manifest an autonomic hyperactivity which is present under general anesthesia. This hyperactivity may contribute to the association of Type A behavior pattern and coronary heart disease.

Aggression↗
PubMedDate not supplied

Cost-benefit analysis of selective screening criteria for Chlamydia trachomatis infection in women attending Colorado family planning clinics.

Women attending family planning clinics in Colorado during 1988 were screened for Chlamydia trachomatis infection by enzyme immunoassay (EIA, Chlamydiazyme, Abbott Laboratories; Abbott Park, IL). Cervical specimens from 11,793 women attending 22 family planning clinics were analyzed. Patient history and physical exams were used to assess risk factors for infection. A total of 913 individuals (7.7%) had positive culture results for C. trachomatis. Multivariate analysis showed that infection was significantly related to endocervical bleeding, cervical mucopurulent discharge, a new sexual partner in the last 3 months or multiple previous sexual partners (greater than 3) in the last year, pregnancy, the use of oral contraceptives, and age. Increased odd ratios were observed for the combination of endocervical bleeding and mucopurulent discharge and sexual history that included partners over the previous year as well as the most recent 3 months. A combination of these criteria was used to selectively screen women attending Colorado family planning clinics on an ongoing basis. A cost-benefit analysis employing a model reported previously showed a significant financial benefit associated with universal screening over either selective screening or no screening for C. trachomatis in this population.

Adolescent↗
PubMed1999

Influence of oxcarbazepine and methsuximide on lamotrigine concentrations in epileptic patients with and without valproic acid comedication: results of a retrospective study.

The aim of this retrospective study was to investigate the influence of oxcarbazepine (OCBZ) and methsuximide (MSM) on lamotrigine (LTG) serum concentrations. The effect of OCBZ compared to carbamazepine (CBZ) and the effect of MSM on LTG serum concentrations were examined in patients with and without valproic acid (VPA) comedication. Altogether, 376 samples from 222 patients were analyzed in routine drug monitoring. Two or more serum samples from the same patient were considered only if the comedication had been changed. For statistical evaluation, regression analytical methods and an analysis of variance were performed. For the analysis of variance, the LTG serum concentration in relation to LTG dose/ body weight--level-to-dose ratio (LDR), in (microg/mL)/(mg/kg)--was calculated and compared for different drug combinations. The nonlinear regression analysis including the LTG dose per body weight, age, gender, and the different kinds of comedication revealed that these variables have a significant influence on LTG serum concentration (r2 = 0.724). The relationship between LTG dose/body weight and serum concentration deviates only slightly from linearity, the LTG concentration was about 18% lower in women than in men, and age had a significant influence. The data indicate that children have significantly lower LTG concentrations than adults on a comparable LTG dose per body weight and that children may be more prone to enzyme induction by comedicated drugs. Methsuximide has a strong inducing effect on the LTG metabolism and decreases the LTG concentrations markedly (about 70% compared to LTG monotherapy). Carbamazepine also reduces the LTG concentrations considerably (by 54%). The inducing effect of OCBZ (29%) was less pronounced but also significant. The inducing effect of MSM, CBZ, and OCBZ was also seen in combination with VPA: VPA alone increases the LTG concentration approximately 211%, whereas in addition to MSM (8%), CBZ (21%), or OCBZ (111%), the increase of LTG was significantly smaller. The analysis of variance confirmed the results of the regression analysis. The effect of MSM on the LTG concentration should be considered if MSM is added or withdrawn in patients treated with LTG. Oxcarbazepine had a less pronounced inducing effect on LTG metabolism compared to CBZ. If CBZ is replaced by OCBZ as comedication, an increase in LTG serum concentrations should be expected.

Adolescent↗
PubMed2006

Differences in workers' compensation disability and impairment ratings under old and new California law.

BACKGROUND: California's workers' compensation law experienced an historic change on January 1, 2005. Previous methods used to rate permanent disability were replaced by new methods to rate permanent impairment. We sought to estimate the difference in ratings under the old and new law. METHODS: We obtained 218 reports on injured workers from attorneys who represented injured workers. A disability expert rated disability and 15 physicians rated impairment. RESULTS: Average percentage point ratings for impairment under the 2005 law were approximately one third the size of ratings for disability under the old law. This estimate showed little variation across demographic groups, physician-evaluators, or injured body part. CONCLUSION: Because cash benefits are keyed to impairment ratings, benefits for permanently disabled workers may decrease as much as 60% under the new law.

Age Distribution↗
PubMed2005

Surrogate end point for prostate cancer specific mortality in patients with nonmetastatic hormone refractory prostate cancer.

PURPOSE: We determined whether prostate specific antigen (PSA) velocity can serve as surrogate end point for prostate cancer specific mortality (PCSM) in patients with nonmetastatic, hormone refractory prostate cancer. MATERIALS AND METHODS: The study cohort comprised 919 men treated from 1988 to 2002 at 1 of 44 institutions with surgery (560) or radiation therapy (359) for clinical stages T1c-4NxMo prostate cancer, followed by salvage hormonal therapy for PSA failure. All patients experienced PSA defined recurrence while on hormonal therapy. Prentice criteria require that the surrogate should be a prognostic factor and the treatment used did not alter time to PCSM following achievement of the surrogate end point. These criteria were tested using Cox regression. All statistical tests were 2-sided. RESULTS: PSA velocity greater than 1.5 ng/ml yearly was statistically significantly associated with time to PCSM and all cause mortality following PSA defined recurrence while undergoing hormonal therapy (Cox p <0.0001). While initial treatment was statistically associated with time to PCSM and all cause mortality (Cox p = 0.001 and 0.01), this association became insignificant when PSA velocity and potential confounding variables were included in the Cox model (p = 0.22 and 0.93, respectively). The adjusted HR for PCSM in patients who experienced a greater than 1.5 ng/ml increase in PSA within 1 year while on hormonal therapy was 239 (95% CI 10 to 5,549). CONCLUSIONS: These data provide evidence to support PSA velocity greater than 1.5 ng/ml yearly as a surrogate end point for PCSM in patients with nonmetastatic, hormone refractory prostate cancer. Enrolling these men onto clinical trials evaluating the impact of chemotherapy on time to bone metastases and PCSM is warranted.

Aged↗
PubMed2003

Minority youth in foster care: managed care and access to mental health treatment.

BACKGROUND: Public sector mental health treatment has been transformed in recent years by the advent of managed care, but investigators of managed care policy have not yet focused on ethnic minority children, especially those involved with the child welfare system. Because of an overrepresentation of high-need minority children, foster care in particular is important to consider. OBJECTIVES: The present study examined children placed in foster care and documented differences between minority children and youth (black persons, Hispanic persons, and white persons) in use of mental health services. The primary concern of the study was to consider whether there were differences in access to services or service use among the groups in the transition to capitated managed care. MATERIALS AND METHODS: Medicaid claims and encounter data for two experimental managed care sites and one comparison fee-for-service site are used in a "difference-in-difference" analysis to estimate a changes in inpatient, outpatient, and residential treatment center (RTC) utilization, controlling for patient characteristics. RESULTS: The study finds persistent declines in inpatient and outpatient use for all ethnic groups, persistent under-representation of Hispanic persons and black persons in treatment regardless of managed care, and greater use of RTCs by black persons and Hispanic persons that is attributable in part to managed care. CONCLUSIONS: Black and Hispanic children received more rather than less mental health care under capitated managed care. The significance of this shift, largely increased in use of RTCs, however, cannot be determined at present, as the effectiveness of treatment delivered in RTCs is not known.

Adolescent↗
PubMed2005

Do patients consistently report comorbid conditions over time?: results from the prostate cancer outcomes study.

BACKGROUND: Comorbidity is an important dimension of patient health status. However, limited attention has been given to assessing the reliability of patient-reported data on comorbid conditions. OBJECTIVES: We sought to evaluate the consistency of self-report of 12 comorbid conditions at 3 distinct time points and examine the sociodemographic, clinical, health status, and survey factors associated with reliability. STUDY DESIGN: We undertook a longitudinal cohort analysis of survey and medical record abstract data obtained from a population-based sample of 3095 prostate cancer survivors. METHODS: Consistent and inconsistent response patterns were assessed using descriptive statistics and regression modeling. RESULTS: More than half of the cohort demonstrated consistent responses to all comorbid condition questionnaire items. Arthritis had the highest (13%) and liver disease the lowest (1%) proportion of inconsistent responses. Older age, lower income, and poorer general and mental health status were significant predictors of inconsistent responses. Subset analyses of the 4 most prevalent comorbid conditions (ie, arthritis, diabetes, hypertension, and depression) showed that respondents who reported that they were limited by, or taking prescription medicine for, the condition were more likely to provide consistent responses than those neither limited nor taking medicine. Response consistencies of 92% or better were obtained for 11 of the 12 conditions. CONCLUSIONS: Men with a relatively recent prostate cancer diagnosis are generally able to provide reliable reports of their concomitant health conditions. To increase the likelihood of obtaining reliable data, investigators should consider ascertaining condition severity and current medical management when querying subjects about comorbid conditions in surveys.

Adult↗
PubMed2005

Standardized assessment of breast cancer surgical scars integrating the Vancouver Scar Scale, Short-Form McGill Pain Questionnaire, and patients' perspectives.

BACKGROUND: Currently, there is no standardized, comprehensive method to assess surgical scars after breast cancer surgery. This article evaluates the application of the Vancouver Scar Scale, in conjunction with patients' scar self-rating and scar-related pain, in a cohort of breast cancer patients. METHODS: Data were prospectively collected in 59 women with breast cancer. Scar assessment comprised: 1. objective rating by pairs of independent observers using the Vancouver Scar Scale; 2. patient's ratings of the scar's physical parameters and overall satisfaction; and 3. pain assessment using the Short-Form McGill Pain Questionnaire. A total of 212 scar scores (59 pairs of breast/chest wall and 47 pairs of axillary scar scores) were generated by 13 observers: three physicians, five radiation therapists, and five nurses. Internal consistency was tested using Cronbach's alpha statistics. Interobserver reliability was evaluated with Spearman's rho and intraclass correlation coefficient computations. Convergent validity of the observer and patient ratings was examined with Spearman's correlation statistics. Linear regression analysis was performed to identify significant factors associated with Vancouver Scar Scale scores and patient satisfaction. RESULTS: The Vancouver Scar Scale, patient self-rating scale, and Short-Form McGill Pain Questionnaire had acceptable internal consistency (Cronbach's alpha 0.79, 0.64, and 0.72 respectively). Interobserver reliability using the Vancouver Scar Scale was significant with Spearman's correlation coefficients of 0.53 for pliability, 0.47 for scar height, 0.49 for vascularity, 0.54 for pigmentation, and 0.66 for overall score (all p values < 0.001). Significant agreement between observer and patient ratings of scar pliability (p = 0.01) and color (p = 0.001) was demonstrated. Mild to moderate pain was reported by more than 40 percent of patients. Patient satisfaction was significantly associated with self-rating of scar pliability and pain, but not Vancouver Scar Scale scores. CONCLUSIONS: The Vancouver Scar Scale is a reliable and valid tool to objectively evaluate scars after breast cancer surgery. Evaluation of scar-related pain and patients' scar rating and satisfaction provide additional information relevant to scar assessment. This integrated approach is feasible in a busy clinical setting to advance care and research in scar management for breast cancer patients.

Adult↗
PubMedDate not supplied

Hypertension in older adults and the role of positive emotions.

OBJECTIVE: Negative emotions have been linked to increases in blood pressure, but relations between positive emotion and blood pressure have not been investigated. Our aim was to test the hypothesis that high positive emotion would be associated with lower blood pressure in older adults. METHODS: A cross-sectional study included 2564 Mexican Americans aged 65 or older living in one of five southwestern states. Primary measures included blood pressure and positive emotion score. Data analyses included descriptive and categorical statistics and regression and cumulative logit analysis. RESULTS: The average age was 72.5 years, 52.8% were women, and 32.8% were on antihypertensive medication. For individuals not on antihypertensive medication, increasing positive emotion score was significantly associated with lower systolic (b = -0.35, standard error (SE) = 0.10) and diastolic (b = -0.56, SE = 0.07) blood pressure after adjusting for relevant risk factors; for those on antihypertensive medication, increasing positive emotion score was significantly associated with lower diastolic (b = -0.46, SE = 0.11) blood pressure, but not systolic blood pressure. Positive emotion was significantly associated with a four-level joint blood pressure variable. Each one-point increase in positive emotion score was associated with a 3% and 9% decreased odds of being in a higher blood pressure category for those on (odds ratio (OR) = 0.97; 95% confidence interval (CI) = 0.93-1.00) and not on (OR = 0.91; 95% CI = 0.89-0.93) antihypertensive medication, respectively. CONCLUSIONS: Findings indicate an association between high positive emotion and lower blood pressure among older Mexican Americans. Targeting the emotional health of older adults might be considered part of nonpharmacologic hypertension treatment programs or as part of adjunctive therapy for those on antihypertensive medication.

Aged↗
PubMedDate not supplied

Correlation of Risser sign and bone age determination in adolescent idiopathic scoliosis.

At the present, there appears to be a lack of unanimity in the choice of whether the Risser sign (iliac apophysis maturation) or determination of skeletal maturation by bone age roentgenograms is the more accurate indicator of maturity in adolescent idiopathic scoliosis. In an effort to clarify this issue, the authors correlated data from 111 patients to determine the relationship between accuracy of Risser sign and bone age determinations performed during similar chronologic intervals. Data from bone age determinations were then correlated with Risser sign data, and a regression line statistical determination was made. The iliac crest apophysis maturation was statistically significantly (p less than 0.01) correlated with data retrieved by skeletal age assessment.

Adolescent↗