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F A Lederle

Publications and source records attributed to F A Lederle.

At least 19 recordsLinked to original sources
PubMed2000

The aneurysm detection and management study screening program: validation cohort and final results. Aneurysm Detection and Management Veterans Affairs Cooperative Study Investigators.

BACKGROUND: We previously reported the prevalence and associations of abdominal aortic aneurysm (AAA) in 73451 veterans aged 50 to 79 years who underwent ultrasound screening. OBJECTIVE: To understand the prevalence of and principal positive and negative risk factors for AAA, and to assess reproducibility of our previous findings. METHODS: In the new cohort of veterans undergoing screening, 52 745 subjects aged 50 to 79 without history of AAA underwent successful ultrasound screening for AAA, after completing a questionnaire on demographics and potential risk factors. RESULTS: We detected AAA of 4.0 cm or larger in 613 participants (1.2%; compared with 1.4% in the earlier cohort). The direction and magnitude of the important associations reported in the first cohort were confirmed. Respective odds ratios for the major associations with AAA for the second and for the combined cohorts were as follows: 1.81 and 1.71 for age (per 7 years), 0.12 and 0. 18 for female sex, 0.59 and 0.53 for black race, 1.94 and 1.94 for family history of AAA, 4.45 and 5.07 for smoking, 0.50 and 0.52 for diabetes, and 1.60 and 1.66 for atherosclerotic diseases. The excess prevalence associated with smoking accounted for 75% of all AAAs of 4.0 cm or larger in the total population of 126 196. Associations for AAA of 3.0 to 3.9 cm were similar but tended to be somewhat weaker. CONCLUSIONS: Our findings confirm our previous cohort findings. Age, smoking, family history of AAA, and atherosclerotic diseases remained the principal positive associations with AAA, and female sex, diabetes, and black race remained the principal negative associations.

Aged↗
PubMed2000

Yield of repeated screening for abdominal aortic aneurysm after a 4-year interval. Aneurysm Detection and Management Veterans Affairs Cooperative Study Investigators.

BACKGROUND: Little is known about the rate at which new abdominal aortic aneurysms (AAAs) develop or whether screening older men for AAA, if undertaken, should be limited to once in a lifetime or repeated at intervals. METHODS: A large population of veterans, aged 50 through 79 years, completed a questionnaire and underwent ultrasound screening for AAA. Of these, 5151 without AAA on the initial ultrasound (defined as infrarenal aortic diameter of 3.0 cm or larger) were selected randomly to be invited for a second ultrasound screening after an interval of 4 years. Local records and national databases were searched to identify deaths and AAA diagnoses made during the study interval in subjects who did not attend the rescreening. RESULTS: Of the 5151 subjects selected for a second screening, 598 (11.6%) had died (none due to AAA), and 20 (0.4%) had an interim diagnosis of AAA. A second screening was performed on 2622 (50.9%), of whom 58 (2.2%; 95% confidence interval, 1.6%-2.8%) had new AAA. Three new AAAs were 4.0 to 4.9 cm, 10 were 3.5 to 3.9 cm, and 45 were 3.0 to 3.4 cm. Independent predictors of new AAA at the second screening included current smoker (odds ratio, 3.09; 95% confidence, 1.74-5.50), coronary artery disease (odds ratio, 1.81; 95% confidence interval, 1.07-3.07), and, in a separate model using a composite variable, any atherosclerosis (odds ratio, 1.97; 95% confidence interval, 1.16-3.35). Adding the interim and rescreening diagnosis rates suggests a 4-year incidence rate of 2.6%. Rescreening only in subjects with infrarenal aortic diameter of 2.5 cm or greater on the initial ultrasound would have missed more than two thirds of the new AAAs. CONCLUSIONS: A second screening is of little practical value after 4 years, mainly because the AAAs detected are small. However, the incidence that we observed suggests that a second screening after longer intervals (ie, more than 8 years) may provide yields similar to those seen in initial screening and therefore warrants further study.

Aged↗
PubMed2000

The accuracy of physical examination to detect abdominal aortic aneurysm.

BACKGROUND: Abdominal palpation during physical examination is an important means of detecting abdominal aortic aneurysm (AAA), but limited information is available on its accuracy. METHODS: Two hundred subjects (aged 51-88 years), 99 with and 101 without AAA as determined by previous ultrasound, each underwent physical examination of the abdomen by 2 internists who were blinded to each other's findings and to the ultrasound diagnosis. RESULTS: The overall accuracy of abdominal palpation for detecting AAA was as follows: sensitivity, 68% (95% confidence interval [CI], 60%-76%); specificity, 75% (95% CI, 68%-82%); positive likelihood ratio, 2.7 (95% CI, 2.0-3.6); negative likelihood ratio 0.43 (95% CI, 0.33-0.56). Interobserver pair agreement for AAA vs no AAA between the first and second examinations was 77% (kappa = 0.53). Sensitivity increased with AAA diameter, from 61% for AAAs of 3.0 to 3.9 cm, to 69% for AAAs of 4.0 to 4.9 cm, 72% for AAAs of 4.0 cm or larger, and 82% for AAAs of 5.0 cm or larger. Sensitivity in subjects with an abdominal girth less than 100 cm (40-in waistline) was 91% vs 53% for girth of 100 cm or greater (P<.001). When girth was 100 cm or greater and the aorta was palpable, sensitivity was 82%. When girth was less than 100 cm and the AAA was 5.0 cm or larger, sensitivity was 100% (12 examinations). Factors independently associated with correct examination findings included AAA diameter (odds ratio [OR], 1.95 per centimeter increase; 95% CI, 1.06-3.58); abdominal girth (OR, 0.90 per centimeter increase; 95% CI, 0.87-0.94); and the examiner's assessment that the abdomen was not tight (OR, 2.68; 95% CI, 1.17-6.13). CONCLUSIONS: Abdominal palpation has only moderate overall sensitivity for detecting AAA, but appears to be highly sensitive for diagnosis of AAAs large enough to warrant elective intervention in patients who do not have a large girth. Abdominal palpation has good sensitivity even in patients with a large girth if the aorta is palpable.

Abdomen↗
PubMed2000

Aneurysm diameter.

Explore the source record for details and available documents.

Aortic Aneurysm, Abdominal↗
PubMed1999

The rational clinical examination. Does this patient have abdominal aortic aneurysm? .

In the physical examination of abdominal aortic aneurysm (AAA), the only maneuver of demonstrated value is abdominal palpation to detect abnormal widening of the aortic pulsation. Palpation of AAA appears to be safe and has not been reported to precipitate rupture. The best evidence on the accuracy of abdominal palpation comes from 15 studies of patients not previously known to have AAA who were screened with both abdominal palpation and ultrasound. When results from these studies are pooled, the sensitivity of abdominal palpation increases significantly with AAA diameter (P<.001), ranging from 29% for AAAs of 3.0 to 3.9 cm to 50% for AAAs of 4.0 to 4.9 cm and 76% for AAAs of 5.0 cm or greater. Positive and negative likelihood ratios with 95% confidence intervals (CIs) using a cutoff point for AAAs of 3.0 cm or greater are 12.0 (95% CI, 7.4-19.5) and 0.72 (95% CI, 0.65-0.81), respectively, and for AAAs of 4.0 cm or greater are 15.6 (95% CI, 8.6-28.5) and 0.51 (95% CI, 0.38-0.67). The positive predictive value of palpation for AAA of 3.0 cm or greater in these studies was 43%. Limited data suggest that abdominal obesity decreases the sensitivity of palpation. Abdominal palpation specifically directed at measuring aortic width has moderate sensitivity for detecting an AAA that would be large enough to be referred for surgery but cannot be relied on to exclude AAA, especially if rupture is a possibility.

Aneurysm, Ruptured↗
PubMed1998

Oral cobalamin for pernicious anemia: back from the verge of extinction.

BACKGROUND: High dose oral cobalamin therapy was shown to be effective for pernicious anemia and other cobalamin deficiency states 30 years ago, and physicians and patients state that they would find oral therapy useful, but a survey conducted in 1989 found that physicians were generally unaware of it. OBJECTIVE: To assess physician awareness and use of oral cobalamin since 1989. DESIGN, SETTING, AND PARTICIPANTS: Minneapolis area internists not listed as having subspecialties or academic business addresses were surveyed in 1989 and in 1996. MEASUREMENTS AND RESULTS: There were 245 responses to the 1989 survey and 223 responses to the 1996 survey for response rates of 68% and 69%, respectively. The percentage of internists who ever used oral cobalamin to treat pernicious anemia increased from 0 in 1989 to 19% in 1996 (P < .001). The percentage who were aware of an effective oral cobalamin preparation for treating cobalamin deficiency states also increased significantly from 4 to 29% (P < .001). The percentage of internists who agreed with the incorrect view that sufficient quantities of cobalamin cannot be absorbed when given orally declined from 91% in 1989 to 71% in 1996 (P < .001). CONCLUSION: Minneapolis internists' awareness and use of oral cobalamin treatment for pernicious anemia increased substantially between 1989 and 1996, but the majority of internists remained unaware of this treatment option.

Administration, Oral↗
PubMed1997

Prevalence and associations of abdominal aortic aneurysm detected through screening. Aneurysm Detection and Management (ADAM) Veterans Affairs Cooperative Study Group.

BACKGROUND: Independent risk factors for abdominal aortic aneurysm (AAA) have not been clearly defined in multivariable analyses of large patient populations. OBJECTIVE: To identify factors that are independently associated with AAA and to determine the prevalence of previously unrecognized AAA in defined demographic and risk groups. DESIGN: Cross-sectional screening study. SETTING: 15 Department of Veterans Affairs medical centers. PARTICIPANTS: 73451 veterans who were 50 to 79 years of age and had no history of AAA. MEASUREMENTS: The results of ultrasonographic screening for AAA and a prescreening questionnaire were analyzed using multiple logistic regression. RESULTS: An AAA of 4.0 cm or larger was detected in 1031 participants (1.4%). Smoking was the risk factor most strongly associated with AAA; the odds ratio (OR) for AAAs of 4.0 cm or larger compared with normal aortas (infrarenal aortic diameter < 3.0 cm) was 5.57 (95% CI, 4.24 to 7.31). The association between smoking and AAA increased significantly with the number of years of smoking and decreased significantly with the number of years after quitting smoking. The excess prevalence associated with smoking accounted for 78% of all AAAs that were 4.0 cm or larger in the study sample. Female sex (OR, 0.22 [CI, 0.07 to 0.68]), black race (OR, 0.49 [CI, 0.35 to 0.69]), and presence of diabetes (OR, 0.54 [CI, 0.44 to 0.65]) were negatively associated with AAA. A family history of AAA was positively associated with AAA (OR, 1.95 [CI, 1.56 to 2.43]) but was reported by only 5.1% of participants. Other independently associated factors included age, height, coronary artery disease, any atherosclerosis, high cholesterol levels, and hypertension. CONCLUSIONS: Abdominal aortic aneurysm is associated with multiple factors. Smoking was the risk factor most strongly associated with AAA and may be responsible for most clinically important cases of previously undiagnosed AAA.

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PubMed1997

Relationship of age, gender, race, and body size to infrarenal aortic diameter. The Aneurysm Detection and Management (ADAM) Veterans Affairs Cooperative Study Investigators.

PURPOSE: To assess the effects of age, gender, race, and body size on infrarenal aortic diameter (IAD) and to determine expected values for IAD on the basis of these factors. METHODS: Veterans aged 50 to 79 years at 15 Department of Veterans Affairs medical centers were invited to undergo ultrasound measurement of IAD and complete a pre-screening questionnaire. We report here on 69,905 subjects who had no previous history of abdominal aortic aneurysm (AAA) and no ultrasound evidence of AAA (defined as IAD > or = 3.0 cm). RESULTS: Although age, gender, black race, height, weight, body mass index, and body surface area were associated with IAD by multivariate linear regression (all p < 0.001), the effects were small. Female sex was associated with a 0.14 cm reduction in IAD and black race with a 0.01 cm increase in IAD. A 0.1 cm change in IAD was associated with large changes in the independent variables: 29 years in age, 19 cm or 40 cm in height, 35 kg in weight, 11 kg/m2 in body mass index, and 0.35 m2 in body surface area. Nearly all height-weight groups were within 0.1 cm of the gender means, and the unadjusted gender means differed by only 0.23 cm. The variation among medical centers had more influence on IAD than did the combination of age, gender, race, and body size. CONCLUSIONS: Age, gender, race, and body size have statistically significant but small effects on IAD. Use of these parameters to define AAA may not offer sufficient advantage over simpler definitions (such as an IAD > or = 3.0 cm) to be warranted.

Aged↗
PubMed1996

Risk of rupture of large abdominal aortic aneurysms. Disagreement among vascular surgeons.

BACKGROUND: Many patients with an abdominal aortic aneurysm (AAA) who are cared for by internists are not good candidates for surgery. Elective repair is usually deferred in these patients until the AAA reaches a diameter at which the estimated risk of rupture is believed to outweigh the operative risk. The risk of rupture is usually estimated by a consulting vascular surgeon, but whether these estimates are well-supported or consistent has not previously been assessed. OBJECTIVE: To determine the agreement among vascular surgeons about the risk of rupture of large AAAs. METHODS: All individual members of the Society for Vascular Surgery (Manchester, Mass) residing in the United States were mailed a survey asking for their estimates of the likelihood of rupture of large AAAs. RESULTS: The response rate was 66% and the 257 respondents who reported that they were practicing vascular surgeons constitute the study group. The median estimates of the 1-year risk of rupture were 20% for 6.5-cm AAAs and 30% for 7.5-cm AAAs, with one third of respondents estimating 50% or greater risk of rupture for 7.5-cm AAAs and nearly one third estimating 50% or greater risk of rupture for 6.5-cm AAAs. The responses spanned a wide range and were generally much higher than would be expected based on published data and estimates. CONCLUSIONS: This survey demonstrates profound disagreement among vascular surgeons about the risk of rupture of large AAAs, reflecting a lack of pertinent published data. Better data are necessary and are being collected.

Aortic Aneurysm, Abdominal↗
PubMed1995

Variability in measurement of abdominal aortic aneurysms. Abdominal Aortic Aneurysm Detection and Management Veterans Administration Cooperative Study Group.

PURPOSE: The purpose of this study was to report interobserver and intraobserver variability of computed tomography (CT) measurements of abdominal aortic aneurysm (AAA) diameter and agreement between CT and ultrasonography observed in the course of a large, multicenter, randomized trial on the management of small AAAs. METHODS: CT measurements of AAA diameter from participating centers were compared with measurements made from the same scan by a central laboratory. Blinded central remeasurement of a randomly selected subset of these CT scans was used to assess intraobserver variability. Agreement between AAA measurements by CT and ultrasonography done within 30 days of each other was also assessed. RESULTS: For interobserver pairs of local and central CT measurements of AAA diameter (n = 806), the difference was 0.2 cm or less in 65% of pairs, but 17% differed by at least 0.5 cm. For intraobserver pairs of central CT remeasurements (n = 70), 90% differed by 0.2 cm or less, 70% were within 0.1 cm, and only one differed by 0.5 cm. Of 258 ultrasound-measured and central CT pairs, the difference was 0.2 cm or less in 44% and at least 0.5 cm in 33%. Ultrasound measurements were smaller than central CT measurements by an average of 0.27 cm (p < 0.0001). Local CT and ultrasound measurements showed a marked preference for recording by half centimeter. CONCLUSIONS: A high degree of precision is possible in CT measurement of AAA diameter, but this precision may not be obtained in practice because of differences in measurement techniques. Differences between imaging modalities increase variability further. Variations in AAA measurement of 0.5 cm or more are not uncommon, and this should be taken into account in management decisions. Efforts to reduce variation in measurement are warranted and might include (1) seeking agreement between surgeons and radiologists on a precise definition of AAA diameter, (2) limiting the number of radiologists who measure AAAs, and (3) use of calipers and magnifying glass for CT measurements.

Aged↗
PubMed1995

Epidemiology of constipation in elderly patients. Drug utilisation and cost-containment strategies.

Constipation is a common complaint among elderly people, resulting in large amounts of money being spent on laxatives. Strategies for improving patient care while reducing this expenditure include: (a) counselling patients that daily bowel movements and purging are not essential to good health, (b) greater use of nonpharmacological measures such as hydration, exercise and dietary fibre, and (c) considering safety, effectiveness and cost in the selection of a laxative. Generic preparations of psyllium and sorbitol can be recommended in this regard. The widespread use of stool softeners, magnesium hydroxide ('milk of magnesia') and stimulant laxatives is difficult to justify from the available data.

Aged↗
PubMed1994

Lung cancer surgery. A critical review of the evidence.

Surgery is generally considered to be the treatment of choice for anatomically localized non-small-cell lung cancer, but its effectiveness remains unproven. Observational studies have been of limited value because the criteria by which patients are selected for surgery create substantial differences between patients who undergo surgery and those who do not. One small randomized trial of surgery vs radiotherapy was inconclusive, but several large trials of lung cancer screening have provided indirect evidence against a benefit from surgery. Two ongoing randomized trials, one on extensive vs limited resection and the other on the effect of surgery in more extensive disease, may provide further insight into the effectiveness of surgery in the treatment of localized non-small-cell lung cancer. Development of a large randomized trial to directly assess the effectiveness of surgery in the treatment of localized non-small-cell lung cancer has been precluded by ethical concerns, but may need to be reconsidered if indicated by the findings of the two ongoing studies.

Carcinoma, Non-Small-Cell Lung↗
PubMed1994

Reduction of unnecessary intravenous catheter use. Internal medicine house staff participate in a successful quality improvement project.

BACKGROUND: We had previously observed that a large proportion of peripheral intravenous (i.v.) catheters placed in patients on a regular medical ward at our hospital were unnecessary. We conducted the current study to assess the effect of a quality improvement project led by medicine house staff on the prevalence of unnecessary peripheral i.v. catheters (those without any therapeutic use, referred to as idle). METHODS: All patients on four regular-care medical wards of a large university-affiliated veterans hospital were included in the study. The proportion of i.v. catheter episodes in which catheters were idle 2 or more consecutive days (idle episodes) and the proportion of patients exposed to an idle catheter episode were determined by direct observation, chart review, and patient interview before and after a multidisciplinary quality improvement task force defined guidelines for appropriate i.v. catheter use and made recommendations for hospital policy changes related to i.v. catheter use. RESULTS: The proportion of all i.v. catheter episodes that were idle catheter episodes decreased significantly after the intervention (42% before vs 29% after, P < .01), as did the proportion of patients with an i.v. catheter who had at least one idle i.v. catheter episode (43% vs 27%, P < .001). CONCLUSIONS: This quality improvement effort successfully reduced unnecessary i.v. catheter use. We suspect that house-staff involvement in the intervention was critical. We encourage other academic medical centers to involve house staff in quality improvement activities to improve patient care and to enhance the education of house staff regarding quality improvement processes.

Catheterization, Peripheral↗