Global urban environmental change drives adaptation in white clover

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.

Temporal patterns of disruptive vocalization in elderly nursing home residents

This study used computer-assisted real-time data collection procedures to study temporal patterns of disruptive vocalization (DV) in demented nursing home residents. Residents (N = 68) were observed from 8 a.m. to 8 p.m. and total mean duration of DV within hourly blocks was calculated. Analysis of the temporal distribution of DV exhibited by the group of 68 residents indicated a significant cubic trend. Exploratory cluster analysis uncovered three distinct temporal patterns of DV; although two of the patterns are generally supportive of sundowning. Cluster 1 showed a relatively constant pattern of low rate DV. Clusters 2 and 3 showed cyclic trends. Peaks in DV were observed during noontime and in the evening for Cluster 2. Cluster 3 showed peaks in DV in the early morning hours and late afternoon. MANOVA was employed to examine any differences among clusters in age, cognitive status, and ADL status. Univariate analyses indicated that cognitive status was the only factor that differed significantly among clusters, with members of Cluster 1 (constant low rate DV) manifesting higher cognitive status scores than Clusters 2 and 3. A step-wise discriminant function analysis also showed cognitive status to be the only statistically significant predictor of cluster membership. The authors' note that the scientific literature on agitation is fraught with contradictory findings and assert that inconsistencies may be due to differences across studies in problem definition, method of measurement, and sample size. The results are discussed in relation to these methodological issues and clinical implications of the findings.

Agitation in nursing home residents: the role of gender and social context

We investigated the relationship among gender of resident, staff social interaction, and agitation in 46 (31 male and 15 female) nursing home residents with clinically significant agitation. Direct observations were conducted of resident behaviors and environmental contextual events using a computer-assisted, real-time observational system. The system recorded frequency, duration, and temporal sequencing of events. Results show that female residents displayed almost three times the amount of agitation as male residents (35% vs. 13% of total observation time, respectively), although men in the study were more likely to receive psychoactive drugs for their agitation. Staff spent similar amounts of time verbally interacting and touching male and female residents. Sequential analyses were conducted to examine the likelihood of staff verbal and touch interactions both preceding and following resident agitation using Bakeman and Quera's (1995) SDIS-GSEQ program. Results suggest that staff touch and verbal interaction elicit agitation in a significant proportion of residents. Once agitation occurs, staff were likely to respond by interacting verbally, but not physically, with the resident.

Natural history of Streptococcus sanguinis in the oral cavity of infants: evidence for a discrete window of infectivity

The heterogeneous group of oral bacteria within the sanguinis (sanguis) streptococci comprise members of the indigenous biota of the human oral cavity. While the association of Streptococcus sanguinis with bacterial endocarditis is well described in the literature, S. sanguinis is thought to play a benign, if not a beneficial, role in the oral cavity. Little is known, however, about the natural history of S. sanguinis and its specific relationship with other oral bacteria. As part of a longitudinal study concerning the transmission and acquisition of oral bacteria within mother-infant pairs, we examined the initial acquisition of S. sanguinis and described its colonization relative to tooth emergence and its proportions in plaque and saliva as a function of other biological events, including subsequent colonization with mutans streptococci. A second cohort of infants was recruited to define the taxonomic affiliation of S. sanguinis. We found that the colonization of the S. sanguinis occurs during a discrete "window of infectivity" at a median age of 9 months in the infants. Its colonization is tooth dependent and correlated to the time of tooth emergence; its proportions in saliva increase as new teeth emerge. In addition, early colonization of S. sanguinis and its elevated levels in the oral cavity were correlated to a significant delay in the colonization of mutans streptococci. Underpinning this apparent antagonism between S. sanguinis and mutans streptococci is the observation that after mutans streptococci colonize the infant, the levels of S. sanguinis decrease. Children who do not harbor detectable levels of mutans streptococci have significantly higher levels of S. sanguinis in their saliva than do children colonized with mutans streptococci. Collectively, these findings suggest that the colonization of S. sanguinis may influence the subsequent colonization of mutans streptococci, and this in turn may suggest several ecological approaches toward controlling dental caries.

Excess disability during morning care in nursing home residents with dementia

Excess disability was examined in 17 nursing home residents with dementia by comparing their performance of morning care tasks under two activities of daily living (ADL) caregiving approaches-a dependence-supportive one under usual care and an independence-supportive one under functional rehabilitation. The results suggest that excess disability in severely cognitively impaired and functionally disabled residents can be reduced by increasing opportunities for independent activity, and substituting nondirective and directive verbal assists for physical assists. Further, the findings indicate that increased independence in ADL can be achieved without increasing disruptive behaviors and can foster appropriate requests for task-related help during caregiving. Functional rehabilitation, however, requires more time than usual care.

Validity and coverage of estimates of relative accuracy

PURPOSE

Studies comparing test accuracy often restrict the confirmation procedure to subjects classified as positive by either test. Relative sensitivity (RSN) and relative false-positive rate (RFP) are two estimable comparative measures of accuracy. This article evaluates the influence of sample size, disease prevalence, and test accuracy on the validity of point estimates of RSN and RFP, and on the coverage of their confidence intervals (CI).

METHODS

For each combination of sample size, disease prevalence, test accuracy, and interdependence between tests 1,000 samples were generated using computer simulations. The percent bias in the RSN and RFP estimates was measured by comparing the means of the 1,000 values computed in each simulation (log-transformed) with their theoretical values. Coverage of the estimated CI was measured by computing the proportion that actually included the theoretical values. Application of these methods was illustrated with data from a study comparing mammography and physical examination in screening for breast cancer.

RESULTS

RSN estimates were valid if the true number of diseased cases exceeded 30, and RFP estimates were valid if the number of nondiseased subjects exceeded 200. When the numbers of diseased and nondiseased subjects exceeded 150 each, the 95% CI of RSN and RFP provided adequate coverage of the parameters (95 +/- 2%).

CONCLUSION

Sample size is the most important variable for the validity and coverage of RSN and RFP estimates. For small samples, validity and coverage of RSN and RFP also depend on the accuracy of each test and on the degree of interdependence between the tests.

Effectiveness of Agency for Health Care Policy and Research clinical practice guideline and patient education methods for pregnant smokers in medicaid maternity care

OBJECTIVE

The purposes of this study were (1) to determine the extent to which tobacco exposure assessment and new patient education methods, derived from a meta-analysis and the Agency for Health Care Policy and Research guideline recommendations, could be provided routinely by trained Medicaid maternity care staff members and (2) to document the behavioral impact of these interventions among pregnant smokers.

STUDY DESIGN

After 265 pregnant smokers were assigned at their first visit to an experimental group (n = 139) or a control group (n = 126), they received standardized risk information and were advised to quit smoking. The experimental group also received evidence-based patient education methods, including the videocassette Commit to Quit During and After Pregnancy, the publication A Pregnant Woman's Guide to Quit Smoking, and a brief counseling session. Self-report and saliva cotinine assessments of tobacco exposure were performed at baseline and at the end of pregnancy.

RESULTS

A significantly higher percentage of patients quit smoking in the experimental group (17.3%) than in the control group (8.8%).

CONCLUSIONS

The application of principles of organizational development and quality improvement at the management and clinical practice levels and the delivery of evidence-based health education methods by trained prenatal care providers significantly increased smoking cessation rates among pregnant Medicaid recipients.

Regression modeling strategies: an illustrative case study from medical rehabilitation outcomes research

The practice of outcomes research is growing in all segments of the health care industry, yet few practitioners and researchers are prepared to deal with the completion of statistical analyses that characterize the new focus on results. This article discusses basic model formulation and interpretation. It also encourages the use of statistical models that study the simultaneous effects of many variables on an outcome and gives examples of relationships among variables that are not simple and linear. The methods are illustrated with a dataset consisting of stroke rehabilitation inpatients discharged during a 3-year period with an admission date that is within 1 year after stroke.

Improving morning care routines of nursing home residents with dementia

OBJECTIVES

This study examined the effectiveness of a behavioral rehabilitation intervention for improving the performance of morning care activities of daily living (ADL) of nursing home residents with dementia.

DESIGN

Participants and their caregivers were observed for 5 days each under conditions of Usual Care (naturalistic) and Skill Elicitation (intervention), and for 15 days under Habit Training (intervention follow-up). Observations involved the ADL categories of DRESSING, OTHER ADL, and NO ADL. A 3 x 3 design (condition x ADL category) was used.

SETTING

Observations occurred in five proprietary nursing homes in Pittsburgh, Pennsylvania.

PARTICIPANTS

The participants were 58 women and 26 men, mean age 82 years (range = 64-97, SD = 6.3), with Probable Alzheimer 's disease (AD) (n = 19) and Possible AD (n = 65), with a mean MMSE score of 6.07.

INTERVENTION

Condition 1, Usual Care, was the naturalistic caregiving condition. Condition 2, Skill Elicitation, consisted of an individualized behavioral rehabilitation intervention designed to identify and elicit retained ADL skills. Under Condition 3, Habit Training, the behavioral rehabilitation intervention was continued to reinforce and solidify retained skills and to facilitate further functional gains.

MEASUREMENTS

A computer-assisted data collection system was used to document in real-time the assists used by caregivers, the participants' ADL performance, and the participants' responses to caregiving, including disruptive behavior.

RESULTS

Compared with Usual Care, during Skill Elicitation participants increased the proportion of time engaged in nonassisted and assisted dressing significantly and increased their overall participation in ADL, with a concomitant significant decrease in disruptive behavior. These functional gains were demonstrated within 5 days of initiating the behavioral rehabilitation intervention and were maintained for 3 weeks during Habit Training. Physical assists were provided for significantly smaller proportions of a morning care session during Skill Elicitation and Habit Training compared with Usual Care.

CONCLUSIONS

Even very severely cognitively impaired and functionally disabled nursing home residents can respond to a systematically implemented behavioral rehabilitation intervention. Their rapid response to this intervention suggests that it is alleviating excess disabilities brought on by care patterns rather than retraining ADL task performance. Residents with dementia benefit from behavioral rehabilitation by becoming more appropriately involved in their care and being less disruptive. However, behavioral rehabilitative care takes considerably more time than usual care.

Behavioral vs drug treatment for urge urinary incontinence in older women: a randomized controlled trial

CONTEXT

Urinary incontinence is a common condition caused by many factors with several treatment options.

OBJECTIVE

To compare the effectiveness of biofeedback-assisted behavioral treatment with drug treatment and a placebo control condition for the treatment of urge and mixed urinary incontinence in older community-dwelling women.

DESIGN

Randomized placebo-controlled trial conducted from 1989 to 1995.

SETTING

University-based outpatient geriatric medicine clinic.

PATIENTS

A volunteer sample of 197 women aged 55 to 92 years with urge urinary incontinence or mixed incontinence with urge as the predominant pattern. Subjects had to have urodynamic evidence of bladder dysfunction, be ambulatory, and not have dementia.

INTERVENTION

Subjects were randomized to 4 sessions (8 weeks) of biofeedback-assisted behavioral treatment, drug treatment (with oxybutynin chloride, possible range of doses, 2.5 mg daily to 5.0 mg 3 times daily), or a placebo control condition.

MAIN OUTCOME MEASURES

Reduction in the frequency of incontinent episodes as determined by bladder diaries, and patients' perceptions of improvement and their comfort and satisfaction with treatment.

RESULTS

For all 3 treatment groups, reduction of incontinence was most pronounced early in treatment and progressed more gradually thereafter. Behavioral treatment, which yielded a mean 80.7% reduction of incontinence episodes, was significantly more effective than drug treatment (mean 68.5% reduction; P=.04) and both were more effective than the placebo control condition (mean 39.4% reduction; P<.001 and P=.009, respectively). Patient-perceived improvement was greatest for behavioral treatment (74.1% "much better" vs 50.9% and 26.9% for drug treatment and placebo, respectively). Only 14.0% of patients receiving behavioral treatment wanted to change to another treatment vs 75.5% in each of the other groups.

CONCLUSION

Behavioral treatment is a safe and effective conservative intervention that should be made more readily available to patients as a first-line treatment for urge and mixed incontinence.

Association rules and data mining in hospital infection control and public health surveillance

OBJECTIVES

The authors consider the problem of identifying new, unexpected, and interesting patterns in hospital infection control and public health surveillance data and present a new data analysis process and system based on association rules to address this problem.

DESIGN

The authors first illustrate the need for automated pattern discovery and data mining in hospital infection control and public health surveillance. Next, they define association rules, explain how those rules can be used in surveillance, and present a novel process and system--the Data Mining Surveillance System (DMSS)--that utilize association rules to identify new and interesting patterns in surveillance data.

RESULTS

Experimental results were obtained using DMSS to analyze Pseudomonas aeruginosa infection control data collected over one year (1996) at University of Alabama at Birmingham Hospital. Experiments using one-, three-, and six-month time partitions yielded 34, 57, and 28 statistically significant events, respectively. Although not all statistically significant events are clinically significant, a subset of events generated in each analysis indicated potentially significant shifts in the occurrence of infection or antimicrobial resistance patterns of P. aeruginosa.

CONCLUSION

The new process and system are efficient and effective in identifying new, unexpected, and interesting patterns in surveillance data. The clinical relevance and utility of this process await the results of prospective studies currently in progress.

The use of an enteral expert system in the prescription of enteral formulas in a university hospital

A personal computer-based expert system has been developed for the prescription of enteral formulas based on patient-need characteristics. Two hundred twelve inpatients in a university hospital setting were prospectively evaluated to compare the identity and cost of the enteral formula prescribed by the expert system with the identity and cost of the enteral formula prescribed by the ward team. Two hundred seven patients had complete data to allow analysis. There was a mean cost savings (+/-SD) of $1.18 +/- 7.69/d for each patient using the expert system compared with the MD-prescribed formula (P = 0.023). We project that the use of this program would save $27,564/y in our hospital (an average of 23,360 patient/days of enteral feeding per year). We conclude that the use of an expert system can be cost-effective in the prescription of enteral formulas for hospitalized patients.

Environmental "white noise": an intervention for verbally agitated nursing home residents

This study presents preliminary data on the efficacy of two environmental "white noise" audiotapes for the treatment of verbal agitation in severely demented nursing home residents. The researchers employed a computer-assisted real-time observational system to assess both the frequency of verbal agitation and the actual use of the intervention on the nursing units (treatment fidelity). Intervention by nurse aides (NAs) on the unit was preceded by a researcher-controlled functional analysis phase that provided information regarding which of the two audiotapes would be most effective for individual residents. Results indicate a 23% reduction in verbal agitation with this individualized treatment strategy on the nursing units. These results were obtained even though treatment fidelity data showed that the audiotapes were used during only 51% of the observations. The authors discuss the need for formal staff management procedures for increasing staff compliance with treatment regimens.

Lack of independent relationships between left ventricular mass and cardiovascular reactivity to physical and psychological stress in the Coronary Artery Risk Development in Young Adults (CARDIA) Study

The objective of this study was to determine whether exaggerated blood pressure (BP) reactivity to stress and psychosocial characteristics are related to left ventricular mass (LVM) in a large cohort of young adults. Analyses were conducted with 3,742 participants of the CARDIA study (945 white men, 1,024 white women, 781 black men, and 992 black women), evaluated in 1990 to 1091 with echocardiographic measurement of LVM. Analyses were stratified by gender and race. The relationships of LVM/height2.7 and cardiovascular reactivity to physical and psychological stressors (treadmill exercise, cold pressor, video game, and star-tracing tasks), were examined in both univariate and multivariate analyses adjusting for baseline BP, weight, and other relevant biobehavioral variables. The relationships between LVM and several psychosocial characteristics (hostility, anger suppression, anxiety, depressive symptoms, and education) were also assessed. Systolic blood pressure (SBP) reactivity to exercise was significantly related to LVM in black and white men; LVM was 10% greater among white men with exaggerated (upper quintile) peak exercise SBP than among other white men. SBP reactivity to the cold pressor test was related to LVM in all race/gender groups, although the relationship remained significant only among white men and women in the multivariate analysis. Diastolic blood pressure (DBP) reactivity to the video game was related to LVM only among black men in adjusted analyses. After adjusting for resting BP, weight, and other covariates in linear multiple regression models, SBP reactivity to exercise explained only 3% of the variance in LVM among white men. Otherwise, reactivity to other stressors or psychosocial variables accounted for no more than 1% of the variance in LVM. It was concluded that among a cohort of young adults, blood pressure reactivity to physical and mental stressors did not add substantially to the prediction of LVM when resting BP, weight, and other covariates were taken into account.

Urinary incontinence during pregnancy in a racially mixed sample: characteristics and predisposing factors

The objectives of the study were to assess the prevalence of urinary incontinence symptoms during pregnancy in a racially mixed sample and to identify potential predisposing variables. Five hundred and twenty-three women were interviewed in the hospital on postpartum day 2 or 3 and by telephone at 6-week follow-up. A significantly larger proportion of white women reported accidental loss of urine than did black women (62.6% vs. 46.4%; P < 0.01). A breakdown by type of incontinence indicated that the race effect was largely attributable to the significantly higher prevalence of the symptom of stress incontinence among white women (P < 0.0001). In stepwise logistic regression modeling, previous incontinence, education level, parity and nocturia were selected as the strongest predictors of incontinence in white women. Attendance at childbirth classes was the only predictor of incontinence for black women. The results raise the possibility that higher rates of incontinence among white women might be due to differences in the pelvic floor.

Nocturnal enuresis in community-dwelling older adults

OBJECTIVE

To investigate the prevalence and characteristics of nocturnal enuresis in community-dwelling older adults and to identify potential predisposing variables.

DESIGN

Interview survey.

SETTING

Five rural counties in northwestern Pennsylvania.

PARTICIPANTS

Subjects were 3884 community-dwelling older adults aged 65 to 79 years who volunteered for a health promotion demonstration.

MEASUREMENTS

The dependent variable was self-reported accidental loss of urine during sleep. Independent variables included demographic variables, self-reported disease history and symptomatology, and standardized screening instruments for depression (CES-D), dementia (MMSE), and functional status (ADLs).

MAIN RESULTS

Prevalence of nocturnal enuresis was 2.1%, and was significantly higher among women (2.9%) compared with men (1.0%; P < .0001). Compared with subjects with daytime incontinence only, those with nocturnal enuresis reported greater severity and impact of incontinence on several parameters. Enuretics were more likely to have received treatment; treatment outcome, however, was significantly less successful. In univariate analyses, enuresis was significantly associated with symptoms of congestive heart failure (CHF), impairment in activities of daily living, depression, and use of sleep medications at least once per week. In stepwise logistic regression modeling, two symptoms of congestive heart failure and regular use of sleep medication entered the model.

CONCLUSIONS

Nocturnal enuresis appears to be uncommon among older adults, but it may be associated with poorer therapeutic outcomes compared with the more common forms of daytime incontinence. The findings are consistent with the hypothesis that daytime fluid accumulation followed at night by mobilization of excess fluid is a contributor to enuresis in older adults.

Correlates and predictors of weight loss in young adults: the CARDIA study

OBJECTIVE

To determine associations of sociodemographic characteristics, behaviors, attitudes and medical factors with weight loss in a population-based biracial cohort of young adults.

DESIGN

Two-year longitudinal observation study.

SUBJECTS

4278 black and white men and women aged 18-30 years in 1985-1986.

MEASUREMENTS

Weight, height, education, income, subscapular skinfold thickness, waist and hip circumferences, medical history, smoking, physical activity, dietary energy, fat and alcohol intake, physical fitness measured by treadmill testing, self-reported dieting, history of weight loss and regain, perception of body size and belief in health consequences of overweight.

RESULTS

Weight loss, defined as reduction of 5% or more of baseline weight, occurred in 8.9% of the cohort, ranging from 4.9% among white men who were not overweight at baseline to 21.5% among white women who were overweight. Weight loss was more common in women than men and in overweight white women than overweight black women. Although findings differed among the four race-sex groups, weight loss was generally associated with greater baseline fatness, lower baseline physical fitness level, self-perception of being overweight, dieting and previous weight loss and regain. Greater baseline fatness, a perception of being overweight and dieting were also associated with weight gain. Among the overweight, low baseline fitness and an increase in physical activity were the factors most consistently associated with weight loss.

CONCLUSION

Weight loss in young adults varies by race, sex and body weight and is associated with a variety of behaviors and attitudes, some of which are also associated with weight gain and, thus, may be associated with weight fluctuation.

Comparison of M-mode and two-dimensional echocardiographic algorithms used to estimate left ventricular mass: the Coronary Artery Risk Development in Young Adults Study

Left ventricular (LV) mass as measured from M-mode echocardiography has been shown to be an important predictor of subsequent cardiovascular morbidity and death. Investigators have debated the advantages of LV mass calculations derived from M-mode versus various two-dimensional (2D) echocardiographic algorithms. The purpose of this study was to compare measurements of LV mass made from M-mode and 2D echocardiographic formulas in 325 healthy young adults of the Coronary Artery Risk Development in Young Adults cohort. M-mode LV mass was calculated according to a necropsy-validated formula, whereas 2D LV mass was calculated according to two established algorithms (i.e., the biplane Simpson and truncated ellipsoid methods). LV mass derived from M-mode echocardiography was 162.7 +/- 52 gm (mean +/- SD). Mean (+/- SD) LV mass derived from 2D echocardiographic measurements were as follows: with the biplane Simpson method (four-chamber view), 164.2 +/- 42 gm; with the biplane Simpson method (two-chamber view), 159.8 +/- 44 gm; with the truncated ellipsoid method (four-chamber view), 139.8 +/- 37 gm; and with the truncated ellipsoid method (two-chamber view), 143.1 +/- 38 gm. Correlations between M-mode and 2D methods ranged from 0.75 to 0.81 (p < 0.0001 for each comparison), and correlations between 2D methods were all greater than 0.90. This study has demonstrated that measurements of LV mass calculated from M-mode and 2D formulas correlate well with each other. Nonetheless, LV mass calculated from the truncated ellipsoid formula averages approximately 20 gm less than that calculated from the 2D biplane Simpson or M-mode echocardiographic formulas. These systematic differences in calculated values for LV mass must be taken into account when choosing an LV mass algorithm for use in cross-sectional and serial studies.

Clinical risk factors for pulmonary barotrauma: a multivariate analysis

Previous investigations have suggested that elevated airway pressures increase the risk of ventilator-induced pneumothorax. However, risk factor analysis using multivariate techniques has not been done. We investigated the hypothesis that airway pressures would not independently correlate with pneumothorax when underlying disease was considered. All ventilated patients over a 1 yr period in the Hohenburg Critical Care Unit at the University of Alabama were followed until death or discharge from the ICU. Ventilator data were collected daily and the presence of pneumomediastinum and pneumothorax determined by review of chest radiographs. Maximal values of airway pressures, minute ventilation, tidal volume, and respiratory rate, as well as age, sex, and underlying disease, were entered into logistic regression analysis. A total of 168 patients was studied, and 20 experienced pneumothorax. Multivariate analysis of the entire ventilated population revealed that only the presence of ARDS independently correlated with pneumothorax. A similar analysis performed on the ARDS population revealed independent correlation only with male sex. Trends toward elevation in airway pressures were seen that did not reach statistical significance. We conclude that development of pneumothorax is most closely correlated with underlying disease, specifically ARDS, and that the associations previously noted between airway pressures and barotrauma largely relate to the occurrence of high airway pressures in ARDS.

Nurses' acceptance of behavioral treatments and pharmacotherapy for behavioral disturbances in older adults

Behavioral disturbances are common in elderly individuals, particularly in those suffering from dementia. Nurses are called on to manage these problem behaviors both in the nursing home and through home health care. There has been growing interest in nonpharmacological interventions for these problems, most notably behavioral therapies. However, until recently, no information was available regarding the acceptance by health care professionals on the use of these treatments with elderly individuals. The purpose of this study was to assess geriatric nurses' acceptance of two behavioral treatments (differential reinforcement of incompatible behavior and time-out from positive reinforcement) and the most commonly used treatment at this time, pharmacotherapy. Nurses were asked to read a clinical case vignette and three treatment descriptions, rating the treatments with Kazdin's Treatment Evaluation Inventory. Results show that both behavioral treatments, including a mildly aversive treatment (time-out) were rated more positively than pharmacotherapy. Nurses modified their ratings in response to described differences in the patient's cognitive functioning and place of residence. Most interesting, acceptability ratings were influenced by characteristics of nurse raters, including the nurses' educational background and the amount of contact with geriatric patients.

Clinical risk factors for pulmonary barotrauma: a multivariate analysis

Previous investigations have suggested that elevated airway pressures increase the risk of ventilator-induced pneumothorax. However, risk factor analysis using multivariate techniques has not been done. We investigated the hypothesis that airway pressures would not independently correlate with pneumothorax when underlying disease was considered. All ventilated patients over a 1 yr period in the Hohenburg Critical Care Unit at the University of Alabama were followed until death or discharge from the ICU. Ventilator data were collected daily and the presence of pneumomediastinum and pneumothorax determined by review of chest radiographs. Maximal values of airway pressures, minute ventilation, tidal volume, and respiratory rate, as well as age, sex, and underlying disease, were entered into logistic regression analysis. A total of 168 patients was studied, and 20 experienced pneumothorax. Multivariate analysis of the entire ventilated population revealed that only the presence of ARDS independently correlated with pneumothorax. A similar analysis performed on the ARDS population revealed independent correlation only with male sex. Trends toward elevation in airway pressures were seen that did not reach statistical significance. We conclude that development of pneumothorax is most closely correlated with underlying disease, specifically ARDS, and that the associations previously noted between airway pressures and barotrauma largely relate to the occurrence of high airway pressures in ARDS.

Elders' acceptability ratings of behavioral treatments and pharmacotherapy for the management of geriatric behavioral disturbances

The management of geriatric behavioral disturbances presents a challenge for both caregivers and care receivers. Previously, we have investigated caregivers' and health care professionals' perceptions of the acceptability of behavioral treatments and pharmacotherapy. However, the perceptions of the potential or actual recipients of these interventions are equally important. In this study, vignette methodology assessed elderly individuals' acceptance of two behavioral treatments and one pharmacologic intervention using Kazdin's Treatment Evaluation Inventory. Respondents assigned the highest treatment acceptability ratings to behavioral treatments and the lowest to drug therapy. The place of patient residence described in the vignettes (community or nursing home) mediated treatment acceptability ratings.

Energy expenditure in children of lean and obese parents

We evaluated whether children of obese parents have defects in energy expenditure in a study of 73 children (5 +/- 0.9 yr of age) of lean and obese parents. Total energy expenditure (TEE) was measured over 14 days by use of doubly labeled water and physical activity energy expenditure (AEE) derived by subtracting resting energy expenditure (REE) under postprandial conditions. Fat and fat-free mass (FFM) were measured in children and parents with use of bioelectrical resistance. There were no significant correlations between TEE, REE, or AEE in children (after adjustment for FFM) and body fat in children or body fat in mothers or fathers. In three-way analysis of covariance (ANCOVA, with FFM as a covariate), there were no significant effects of gender in children, obesity in mothers, or obesity in fathers on TEE or AEE in children. There was a significant effect of gender and a significant interaction between obesity in mothers and obesity in fathers on REE; relative to children with two nonobese or two obese parents, REE was approximately 6% lower in children when mothers only or fathers only were obese. In conclusion, our data do not support the hypothesis that children of obese parents have major defects in energy expenditure.

Early intervention for low birthweight, premature infants: participation and intellectual development

The Infant Health and Development Program was an eight-site randomized controlled trial of comprehensive early intervention for low birthweight, premature infants during the first 3 years of life in which intellectual development was an outcome of major importance. At 24 and 36 months, but not at 12 months, higher Mental Development Index and IQ were associated with higher levels of participation in the intervention. In a longitudinal analysis of these data, we found that the intellectual development of children in the intervention group was associated with each of the three intervention modalities (the number of home visits received, days attended at child centers, and the number of parent meetings attended) but not with children's background characteristics (i.e., maternal education, birthweight). We suggest that these findings represent a dose-response relation between intervention and outcome.

The utility of fetal biometry as an adjunct to the multiple-marker screening test for Down syndrome

OBJECTIVE

Our purpose was to investigate fetal biometry as an adjunct to the multiple-marker screen (maternal age, serum alpha-fetoprotein, estriol, and human chorionic gonadotropin) for Down syndrome.

STUDY DESIGN

Fifty-two cases of Down syndrome were compared with 7514 normal fetuses. The measured/predicted femur length ratio had the best discriminant value (1.0 +/- 0.11 vs 0.93 +/- 0.13, p < 0.0001). Multivariate gaussian algorithms were developed and each computed a likelihood ratio for Down syndrome. The trivariate algorithm incorporated the three maternal analytes, whereas the quadrivariate version also included the femur length ratio. The study population included 38 cases of Down syndrome and 1098 euploid controls. The midtrimester risk was the product of the age-related risk and the likelihood ratio.

RESULTS

The relative difference in the femur length ratio between normal and affected fetuses was small in comparison to that of the maternal serum analytes. At a risk cutoff of > or = 1:190 the detection rates were similar and actually favored the trivariate algorithm but differed only by one case of Down syndrome.

CONCLUSION

The addition of the measured/predicted femur length ratio had a negligible effect on the performance of the multiple-marker screening test.

Studying disruptive vocalization and contextual factors in the nursing home using computer-assisted real-time observation

Disruptive vocalization (DV) is both a prevalent and disturbing problem in nursing homes. We developed a computer-assisted data collection system for real-time observation and recording of DV and various environmental contextual factors. Both frequency and duration of DV were recorded for 11 residents along with their location in the nursing home, their activity, environmental sound, the social environment, and whether or not the resident was physically restrained. The actual time of all events was also recorded. Measures of cognitive and ADL status were administered. The average occurrence of DV was 22 per hour and the average duration per occurrence was 26 seconds. The results show a significant upward linear trend in the occurrence of DV across the day. This is consistent with the "sundowning" hypothesis. A Cox Proportional Hazards Regression model indicates that another person present in the setting (p = .004) and resident presence at the nursing home hairdresser (p = .07) were associated with shorter duration episodes of DV. Correlational analyses indicate that both higher frequency and longer duration DV are related to greater cognitive impairment, and higher frequency DV is related to greater ADL impairment. We conclude that this computer-assisted real-time observational system is a useful and promising tool for studying disruptive behavior in its environmental context.

Dietary habits of first-year medical students assessed during clinical nutrition course

To enhance the Introduction to Clinical Nutrition course at the University of Alabama at Birmingham, medical students taking the course from 1989 to 1992 (n = 616) were required to analyze by computer the nutrient composition of their own diets for a 24-h period. In 1991 and 1992, they were required to repeat the analysis at the completion of the course. Overall, fat comprised 30% of energy intake, and along with saturated fat and the cholesterol-saturated fat index, it declined virtually each year compared with the previous year. Significant changes were noted by the end of the course in 1991 and 1992 compared with the beginning, when fat comprised 26% of energy, and more students adhered to recommendations for dietary fat, saturated fat, and fiber. Vitamin C intakes exceeded the recommended dietary allowance by more than twofold and increased further by the end of the course in 1991 and 1992, probably indicating an increase in fruit and vegetable intake. Each year, most students rated the dietary assessment as moderately or very useful. These data suggest that dietary self-assessment is a useful tool for teaching clinical nutrition in medical schools and that, even before instruction in clinical nutrition, medical students are favorably altering their dietary patterns to a greater extent than the general population.

The statistical analysis of cancer inhibition/promotion experiments

The purpose of this paper is to address the very important problem of accurate statistical analysis of certain types of cancer inhibition/promotion (IP) experiments. These experiments are routinely used by the National Cancer Institute to test the effects of potential chemopreventative agents. The statistical analysis is difficult since there is Type I censoring. In the IP experiments under investigation, laboratory animals (rats) are injected with a single dose of either a direct or indirect acting carcinogen. In the mammary tumor system, animals in the control group generally develop 5-7 tumors and typical experiments are usually terminated after 4-6 months. Animals are sacrificed at the end of the experiment and all observed tumors are confirmed. The two most common response variables are the number of observed tumors per animal and the rate of tumor development. The difficulty in analyzing these experiments occurs because experiments are terminated before all induced tumors have been observed. Fewer observed tumors in one group compared to another could be the result of a decreased number of induced tumors, a decrease in growth rate, or a combination of both. It is essential for the experimenter to distinguish between these two different biological actions. Present statistical techniques do not account for this confounding and since they rely primarily on nonparametric procedures, do not present an accurate description of potential IP agents. In this paper we introduce a parametric procedure that explicitly acknowledges the confounding present in experiments of this nature. The analysis is based on the comparison of the mean number of tumors per group (lambda) and the mean time to tumor appearance (mu). A longer mean time to development is believed to indicate a slower tumor growth rate. Hypothesis tests are developed to determine if there is an overall experiment effect, to isolate which groups are contributing to an observed experiment effect, and to isolate factors (tumor number and/or growth rate) contributing to an observed group difference. Confidence regions for (lambda, mu) are also generated. This analysis leads to a better understanding of how potential IP agents function.

Most peripheral, node-negative, non-small-cell lung cancers have low proliferative rates and no intratumoral and peritumoral blood and lymphatic vessel invasion. Rationale for treatment with wedge resection alone

We investigated the tumor aggressiveness (intratumoral and peritumoral lymphatic and blood vessel invasion by tumor emboli) and proliferative activity (mitotic count) of 45 patients with peripheral, superficially seated, node-negative (T1-2 N0 M0), non-small-cell lung cancer treated with wedge resection alone between January 1982 and June 1988. Most patients were male (n = 39) with T1 (n = 25), small (mean diameter, 2.6 +/- 0.8 cm), squamous (n = 24), right-sided (n = 29) tumors located in either upper lobe (n = 35). The surgical specimens were studied by immunohistochemical staining with a monoclonal antibody targeting the factor VIII-related antigen. None of the tumors had lymphatic peritumoral or intratumoral invasion. Seven neoplasms (15%) harbored blood vessel invasion by tumor cells; all but one of these invasions were within the substance of the tumor. The median mitotic count was 8 mitoses per 10 high-power fields (range, 1 to 42 mitoses), significantly (p = 0.003) higher in patients with blood vessel invasion than in those without. With a 24-month minimum follow-up, projected 3- and 5-year survivals are 79% and 68%, respectively. Eleven patients had relapses and died of their tumors because of either local (n = 5) or extrathoracic (n = 6) recurrence; three patients died without tumors of comorbidity. Among the six tumors recurring in extrathoracic sites, five (83%) harbored intratumoral (n = 4) or peritumoral (n = 1) blood vessel invasion. Both recurrence of disease and death from non-small-cell lung cancer were significantly (p = 0.0009) higher for tumors with blood vessel invasion. By univariate analysis, significant predictors of survival were tumor stage (T1 vs T2, p = 0.008), size (< or = 2.6 cm vs > 2.6 cm, p = 0.039), mitotic count (< or = 8 vs > 8 mitoses, p = 0.0007), and blood vessel invasion (absence vs presence, p = 0.0001). By multivariate analysis, however, only blood vessel invasion retained its level of prognostic significance (p = 0.006). Data demonstrate that peripheral, node-negative non-small-cell lung cancers have a low metastatic potential. Whenever anatomically feasible, wedge resection seems to be an appropriate method of primary treatment.

Acute infection of mice with highly virulent group B streptococci as a host resistance model for immunotoxicity assessment

This report describes a unique model for immunotoxicity evaluation in mice. The model is adapted from previously described mouse models for group B streptococcus (GBS) infections in human neonates. In this disease as well as a number of human diseases caused by highly virulent pathogens, the mechanisms of innate immunity are unable to protect the host, and survival is strictly dependent on acquired immunity. Unlike other host resistance models widely used in immunotoxicity studies, the GBS model utilizes bacteria that are highly virulent for mice (LD50 = 5-17 colony forming units). GBS is not virulent for adult humans and can be safely handled with typical precautions. Acquired immunity in the GBS model is induced during a 2 week period by two injections of heat-killed GBS. The immunizing doses are the minimum which will allow survival of 80-100% of mice in response to challenge with an otherwise lethal dose of live GBS (100 bacteria). Administration of the immunotoxic agents cyclophosphamide, carrageenan, or cobra venom factor during the immunization period and/or shortly before challenge significantly suppressed host resistance. For example, the composite mortality rate for unimmunized mice was 98% and the rate for immunized mice was 8.5%. For all groups treated with cyclophosphamide (one 75 mg/kg dose 48 h before each immunization) the mean mortality was 41 +/- 18%. The consistency of the model was evaluated by repetition of several treatments in independent experiments, and the model's consistency is comparable to that of other host resistance models.(ABSTRACT TRUNCATED AT 250 WORDS)

Septicemia due to Yersinia enterocolitica in a hemodialyzed, iron-depleted patient receiving omeprazole and oral iron supplementation

Septicemia occurred in a long-term hemodialysis patient on oral iron supplementation who had been treated for esophageal ulcer by omeprazole, an ulcer-healing drug. Yersinia enterocolitica serotype 0:3 was recovered from blood cultures. A raised intraintestinal pH and an increased intraluminal iron load may have been contributing factors for the enhanced proliferation and generalized infection of Y enterocolitica.

Medication adherence patterns in chronic obstructive pulmonary disease

While medical treatment of COPD has advanced, the failure to adhere to regimens for medication poses a significant barrier to effective management. Furthermore, no data are available regarding adherence for patients within the United States. Data from this investigation indicate that 78 outpatients from a medical center in the southeastern region of the United States were prescribed an average of 6.26 medications with both various dosing schedules and different modes of administration. Adherence was poor, with 42 patients (54 percent) underutilizing medications, 39 patients (50 percent) overutilizing medications during periods of respiratory distress, and 24 patients (31 percent) employing ineffective inhaler dosing techniques. Prescription patterns and adherence were not associated with demographic variables; however, adherence was related to classes of medication and situational variables.

Methotrexate therapy in rheumatoid arthritis patients diminishes lectin-induced mononuclear cell proliferation

Methotrexate (MTX) is an anti-folate drug used in cancer chemotherapy because of its anti-proliferative effects. However, it is unclear whether the anti-proliferative effects of MTX contribute to the efficacy of low-dose MTX in the treatment of rheumatoid arthritis (RA). To date, either no change or a paradoxical increase in lectin-induced proliferation has been observed in cultures of peripheral blood mononuclear cells (PBMC) from MTX-treated RA patients (RA + MTX). In these earlier studies, high folate-containing media and tritiated thymidine (3H-TdR) were used. Our studies were designed to test the hypothesis that the use of a culture medium with a low folate content along with tritiated deoxyuridine (3H-UdR) permits detection of diminished phytohemagglutinin (PHA)-induced proliferative responses of PBMC from RA + MTX. The data demonstrate decreased PHA-induced cellular proliferation of cultured PBMC from RA + MTX compared with controls. When comparing the PBMC proliferative responses in high vs low folate medium, a significantly greater increase (P less than 0.05) in proliferation occurs in the cells from RA + MTX cultured in the high folate medium. This suggests that an in vivo folate-deficient state of the cells from RA + MTX may be corrected in vitro when a high folate medium is used in culture. We conclude that the use of 3H-UdR and a medium containing folate within the normal range of plasma folate levels eliminates artifacts associated with the use of high folate medium and 3H-TdR, which obscures the anti-proliferative effect of MTX in RA patients.

Effect of retinyl acetate and 4-hydroxyphenylretinamide on initiation of chemically-induced mammary tumors

The anti-promotional effect of retinoids on chemically-induced mammary carcinogenesis in the rat is well established. The present studies were performed to determine the effect of long-term feeding of retinyl acetate and 4-hydroxyphenylretinamide (4-HPR) on initiation of mammary tumors induced by MNU or DMBA. Retinyl acetate (328 mg/kg of diet) or 4-HPR (782 mg/kg of diet) was added to the diet of female Sprague-Dawley rats for two months prior to the administration of the carcinogens. In the MNU model, a 50% increase in the number of mammary adenocarcinomas was observed in rats pretreated with retinyl acetate, while pretreatment with 4-HPR resulted in a 93% increase in the number of cancers. Continued treatment with 4-HPR throughout the study, however, caused a reduction in cancer number. In the DMBA mode, pretreatment with these retinoids significantly increased the number of benign mammary tumors, but not mammary cancers. These data suggest that newly synthesized retinoids should be evaluated for chemopreventive activity against mammary cancer initiation as well as for their anti promotional activity.

Initial evaluation of a human immunoglobulin M monoclonal antibody (HA-1A) in humans

A human monoclonal antibody (HA-1A) directed against bacterial endotoxin was administered to 15 patients with incurable malignant disease. No adverse effects were noted following single intravenous infusions of 0.05 to 100 mg. Pharmacokinetics were evaluated in nine patients receiving 10 mg (n = 3), 25 mg (n = 3), and 100 mg (n = 3). Seven of these patients had initial peak serum concentrations greater than 80% of predicted values with plasma disappearance curves fitting a one-compartment system and a plasma half-life of 31.5 h (range of 20.3-44.6 h). The peak serum concentrations and area under the curve values were proportional to the dose of HA-1A administered. One patient had a hypercatabolic state with low levels of serum albumin and IgM. He achieved 65% of the predicted value for peak serum concentration of HA-1A with a plasma half-life of 12.3 h. A second patient had detectable serum HA-1A for only 15 min following infusion without an adequate technical or biologic explanation. We were unable to demonstrate antibody to HA-1A in sera from these nine patients either prior to therapy or during 28 days postinfusion using a "double-antigen" radiometric assay. This study suggests that HA-1A human monoclonal antibody administration is well tolerated by patients. Phase I trials will need to be carried out to characterize further the pharmacokinetics and toxicity of HA-1A in patients with gram-negative sepsis.

Effect of miso (Japanese soybean paste) and NaCl on DMBA-induced rat mammary tumors

An AIN-76A diet supplemented with miso (Japanese soybean paste) reduced the incidence (p = 0.05, Fishers exact test) and delayed the appearance (p = 0.04, log rank test) of dimethylbenz[a]anthracene (DMBA)-induced mammary adenocarcinomas in female Sprague-Dawley rats. A NaCl-supplemented AIN-76A diet (containing the same amount of NaCl as in the miso-supplemented diet) also delayed the appearance of tumors (p = 0.02, log rank test) compared with the AIN-76A control diet. The miso- and NaCl-supplemented diet treatment groups showed a trend toward a lower number of cancers per animal, a trend toward a higher number of benign tumors per animal, and a trend toward a lower growth rate of cancers compared with controls. However, no statistical differences in the total number of tumors per animal or growth rate of the cancers were observed in the miso, NaCl, and control groups. Both miso and NaCl supplementation resulted in increased water intake and urine output but no change in the growth of the animals. These data suggest that miso consumption may be a factor producing a lower breast cancer incidence in Japanese women.

Decreased egg production in commercial laying hens fed zearalenone- and deoxynivalenol-contaminated grain sorghum

In an experiment to determine the effect of corn vs. grain sorghum on performance of laying hens, egg production decreased significantly in the grain sorghum-fed hens in each of two trials starting 24 weeks after the trials began. Necropsy of chickens fed both diets revealed buccal ulceration at the ventral aspect of the oral cavity and squamous metaplasia of the esophageal glands and submaxillary salivary glands. Lesions were much more severe in the sorghum-fed birds than in the corn-fed birds. Analysis of the grain sorghum and corn revealed the presence of mycotoxins. Zearalenone and deoxynivalenol were present in the grain sorghum, and a lower amount of deoxynivalenol and a trace of aflatoxin B1 were found in the corn. Although mycotoxin levels were low, interaction between these mycotoxins and others may have decreased egg production.

The effect of biological isolation and a molt-inducing regimen on the recovery of Mycoplasma gallisepticum from commercial Leghorn hens

Two trials were conducted to determine the effect of induced molt on the reisolation of Mycoplasma gallisepticum (MG) from commercial leghorn hens that had been eyedrop-inoculated with MG at 10 weeks of age. Chickens were maintained in a conventional floored chicken house on dry litter through 100 weeks of age. At age 64 weeks, 4 days (Trial 1), and at 100 weeks (Trial 2), hens were swabbed and cultured for MG and then molted in biological isolation units. Swabs were again taken at the end of each molt. No difference was observed in the number of MG isolations between molted hens and controls that did not undergo molting. However, a significant decrease in MG isolations was observed in both trials from swabs obtained when hens were housed on dry litter floors as compared with swabs taken from the same hens after 18 days (Trial 1) or 21 days (Trial 2) of confinement in isolation units.

F strain Mycoplasma gallisepticum vaccination of post-production-peak commercial Leghorns and its effect on egg and eggshell quality

Forty-five-week-old commercial leghorns negative for antibodies to Mycoplasma gallisepticum (MG) and M. synoviae were vaccinated with high-passage F strain MG (FMG). Hens were confined in modified Horsfall-Bauer isolation units through 60 weeks of age. Egg production (% hen day) and parameters of egg and eggshell quality were monitored, including egg weight, eggshell strength, Haugh unit score, pimpling, and blood/meat spot incidence. Egg production was significantly lower (P less than 0.05) for FMG vaccinates than controls (down 5.76% and 5.80% in Trials 1 and 2, respectively). However, vaccinates and controls did not differ significantly in eggshell strength, shell thickness, pimpling, or blood/meat spot incidence. Haugh unit scores were significantly (P less than 0.05) greater for FMG vaccinates. At necropsy, all reproductive tracts appeared grossly normal. These studies suggest that high-passage FMG vaccination of post-production-peak hens does not adversely affect oviduct function.

Lung-clearance classification of radionuclides in coal fly ash

Lung-clearance classifications for 238U, 232Th, 230Th, 228Th, 226Ra, 210Pb and 210Po in respirable coal fly ash were estimated for use with the lung clearance model proposed by the ICRP Task Group on Lung Dynamics. Estimates were based on measurements of the dissolution rates for these radionuclides from sized fly-ash samples into simulated lung fluid at 37 degrees C. The estimates were expressed in the classification terms of the model, i.e. D, W and Y, indicating lung clearance half-times of 0-10 days, 11-100 days, and more than 100 days, respectively. Ash from eastern bituminous coal, western bituminous coal and mid-western bituminous coal was examined. Both Class-D and Class-Y components of 238U were found in all samples, whereas all the other radionuclides dissolved very slowly and were classified 100% Class Y. The fraction of 238U in Class D increased with decreasing particle size and increased linearly from 0.02 to 0.17 as the concentration of U in the volatile-metal portion of the samples increased. This relationship suggests that a major fraction of the U in coal fly ash may be shielded from exposure to simulated lung fluid by more-abundant metals deposited on the outer surface of fly ash during coal combustion.

[Primary hyperparathyroidism. Lack of effect of cimetidine on plasma levels of parathyroid hormone and calcium]

Because of the contradictory results formerly published as regards the effect of cimetidine in primary hyperparathyroidism, we have studied the effect of cimetidine at the daily dose of 1200 mg in 14 cases of primary hyperparathyroidism. The diagnosis was ascertained in all cases by the coexistence of an otherwise unexplained hypercalcemia and of a concomitantly elevated plasma concentration of immunoreactive parathyroid hormone (PiPTH) measured by 2 different antibodies and confirmed in 10 cases by surgical neck exploration. In 5 cases with severe hypercalcemia (greater than 12.0 mg/l) cimetidine was discontinued after 5 days because of its lack of effect on both plasma concentrations of calcium and PiPTH, and the patients were successfully operated. In 8 cases with milder hypercalcemia, cimetidine was given for 1.5-6 months. There was no significant change in both plasma concentrations of calcium (PCa) and PiPTH but a regression analysis showed that PCa was negatively correlated to time with a correlation coefficient which would have become significant if the follow-up had been 9 months. In the last patient severe hypercalcemia was controlled by simultaneous administration of phosphate, indomethacin and cimetidine without concomitant decrease of PiPTH; and 6 weeks after cimetidine discontinuation no significant increase of PCa and PiPTH occurred. These data show that cimetidine has no clinically therapeutic value in primary hyperparathyroidism.

[Control of hypertension and blood lactate during exercise. Comparison of central antihypertensive agents with the cardio-selective beta blockers metoprolol and atenolol]

To assess whether betablockers (BB) would better control blood pressure than central antihypertensive drugs (CAD) clonidine or alpha methyldopa in hypertensive patients during exercise, comparable triangular ergometric bicycle exercises were performed by the same patients while their hypertension had been controlled at rest either with CAD or BB. Blood pressure, heart rate and blood lactate before and during exercise were compared in II patients treated with metoprolol and CAD, and in 12 other patients treated with atenolol and CAD. Systolic and diastolic blood pressure on exercise were significantly lower with BB than with CAD. Heart rate and rate-pressure product were always lower with BB than with CAD. Blood lactate increase was greater with BB than with CAD. The work capacity was greater with atenolol than with CAD, but comparable between metoprolol and CAD.

Value of combined intravenous renal arteriography and pyelography in the diagnosis of renovascular hypertension

1. The technique of combined intravenous renal arteriography and pyelography is described and results in 848 hypertensive patients are reported. 2. The procedure was tolerated better than Seldinger arteriography and the diagnostic accuracy for renal artery stenosis was 95%. 3. The prevalence of renovascular disease was 7%. 4. Cost-effectiveness calculations favour combined intravenous arteriography and pyelography rather than the usual approach based on assessment of the indications for Seldinger arteriography from clinical and urographic signs.