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W Browner

Publications and source records attributed to W Browner.

15 recordsLinked to original sources
PubMed2000

Monitoring osteoporosis therapy with bone densitometry: misleading changes and regression to the mean. Fracture Intervention Trial Research Group.

CONTEXT: The principle of "regression to the mean" predicts that patients with unusual responses to treatment might represent outliers who are likely to have more typical responses if treatment is continued without change. OBJECTIVE: To test whether women who lose bone mineral density (BMD) during the first year of treatment for osteoporosis continue to lose BMD if the same treatment is continued beyond 1 year. DESIGN AND SETTING: Two randomized, double-blind, placebo-controlled trials in 11 US clinical research centers for the Fracture Intervention Trial and 180 centers in the United States and other countries for the Multiple Outcomes of Raloxifene Evaluation Trial. PARTICIPANTS AND INTERVENTIONS: Postmenopausal women with low BMD assigned to treatment with 5 mg/d of alendronate sodium in the Fracture intervention Trial who completed 2 years of BMD monitoring and adhered to study medication (n = 2634), and postmenopausal women with osteoporosis assigned to treatment with 60 or 120 mg/d of raloxifene hydrochloride in the Multiple Outcomes of Raloxifene Evaluation trial who similarly completed 2 years of monitoring while adhering to study medication (n = 3954). MAIN OUTCOME MEASURES: Baseline, 12-, and 24-month hip and spine BMD. RESULTS: Women with the greatest loss of BMD during the first year of treatment were the most likely to gain BMD during continued treatment. Specifically, among women taking alendronate whose hip BMD decreased by more than 4% during the first year, 83% (95% confidence interval [CI], 82%-84%)had increases in hip BMD during the second year, with an overall mean increase of 4.7%. In contrast, those who seemed to gain at least 8% during the first year lost an average of 1% (95% CI, 0.1%-1.9%) during the next year. Similar results were observed among women taking raloxifene for 2 years. CONCLUSIONS: Our data suggest that most women who lose BMD during the first year of treatment with alendronate or raloxifene will gain BMD if the same treatment is continued for a second year. These results illustrate the principle of regression to the mean and suggest that effective treatments for osteoporosis should not be changed because of loss of BMD during the first year of use.

Absorptiometry, Photon↗
PubMed1999

Elevated serum estradiol and testosterone concentrations are associated with a high risk for breast cancer. Study of Osteoporotic Fractures Research Group.

BACKGROUND: The relation between endogenous steroid hormones and risk for breast cancer is uncertain. Measurement of sex hormone levels may identify women at high risk for breast cancer who should consider preventive therapies. OBJECTIVE: To test the hypothesis that serum concentrations of estradiol and testosterone predict risk for breast cancer. DESIGN: Prospective case-cohort study. SETTING: Four clinical centers in the United States. PARTICIPANTS: 97 women with confirmed incident breast cancer and 244 randomly selected controls; all women were white, 65 years of age or older, and were not receiving estrogen. MEASUREMENTS: Sex-steroid hormone concentrations were assayed by using serum that was collected at baseline and stored at -190 degrees C. Risk factors for breast cancer were ascertained by questionnaire. Incident cases of breast cancer were confirmed by review of medical records during an average period of 3.2 years. RESULTS: The relative risk for breast cancer in women with the highest concentration of bioavailable estradiol (> or = 6.83 pmol/L or 1.9 pg/mL) was 3.6 (95% CI, 1.3 to 10.0) compared with women with the lowest concentration. The risk for breast cancer in women with the highest concentration of free testosterone compared with those with the lowest concentration was 3.3 (CI, 1.1 to 10.3). The estimated incidence of breast cancer per 1000 person-years was 0.4 (CI, 0.0 to 1.3) in women with the lowest levels of bioavailable estradiol and free testosterone compared with 6.5 (CI, 2.7 to 10.3) in women with the highest concentrations of these hormones. Traditional risk factors for breast cancer were similar in case-patients and controls. Adjustments for these risk factors had little effect on the results. CONCLUSIONS: Estradiol and testosterone levels may play important roles in the development of breast cancer in older women. A single measurement of bioavailable estradiol and free testosterone may be used to estimate a woman's risk for breast cancer. Women identified as being at high risk for breast cancer as determined by these hormone levels may benefit from antiestrogen treatment for primary prevention.

Aged↗
PubMed1999

Association between bone mineral density and cognitive decline in older women.

OBJECTIVE: To test the hypothesis that bone mineral density (BMD), a marker of cumulative estrogen exposure, is associated with cognitive function in nondemented older women. DESIGN: A prospective cohort study. SETTING: Clinical centers in Baltimore, Maryland, Minneapolis, Minnesota, the Monongahela Valley near Pittsburgh, Pennsylvania, and Portland, Oregon. PARTICIPANTS: We evaluated 8333 older community-dwelling women enrolled in the Study of Osteoporotic Fractures who were not taking estrogen replacement. MEASUREMENTS: Calcaneal and hip BMD were measured at baseline and at follow-up (4-6 years later); vertebral fractures were ascertained radiologically at year 6. Women were administered a modified Mini-Mental State Exam, Trails B, and Digit Symbol at baseline and at follow-up. RESULTS: Compared with women with higher bone mineral density, women with low baseline BMD had up to 8% worse baseline cognitive scores (P = .001) and up to 6% worse repeat cognitive scores (P = .001), even after multivariate adjustments. For 1 SD decrease in baseline hip BMD or calcaneal BMD, women had a 32% (95% CI, 19-47%) or a 33% (95% CI, 20-48%) greater odds of cognitive deterioration (worst 10th percentile of change). Women with vertebral fractures had lower cognitive test scores and a greater odds of cognitive deterioration than those without fractures (OR = 1.29; 95% CI, 1.03-1.60). CONCLUSIONS: Women with osteoporosis, whether measured by baseline BMD, reductions in BMD, or vertebral fractures, have poorer cognitive function and greater risk of cognitive deterioration. Our findings suggest a link between two of the most common conditions affecting older women. Further understanding of this association may be important for new treatment and prevention directions.

Absorptiometry, Photon↗
PubMed1998

Prophylactic atenolol reduces postoperative myocardial ischemia. McSPI Research Group.

BACKGROUND: Perioperative myocardial ischemia occurs in 20-40% of patients at risk for cardiac complications and is associated with a ninefold increase in risk for perioperative cardiac death, myocardial infarction, or unstable angina, and a twofold long-term risk. Perioperative atenolol administration reduces the risk of death for as long as 2 yr after surgery. This randomized, placebo-controlled, double-blinded trial tested the hypothesis that perioperative atenolol administration reduces the incidence and severity of perioperative myocardial ischemia, potentially explaining the observed reduction in the risk for death. METHODS: Two-hundred patients with, or at risk for, coronary artery disease were randomized to two study groups (atenolol and placebo). Monitoring included a preoperative history and physical examination and daily assessment of any adverse events. Twelve-lead electrocardiography (ECG), three-lead Holter ECG, and creatinine phosphokinase with myocardial banding (CPK with MB) data were collected 24 h before until 7 days after surgery. Atenolol (0, 5, or 10 mg) or placebo was administered intravenously before induction of anesthesia and every 12 h after operation until the patient could take oral medications. Atenolol (0, 50, or 100 mg) was administered orally once a day as specified by blood pressure and heart rate. RESULTS: During the postoperative period, the incidence of myocardial ischemia was significantly reduced in the atenolol group: days 0-2 (atenolol 17 of 99 patients; placebo, 34 of 101 patients; P = 0.008) and days 0-7 (atenolol, 24 of 99 patients; placebo, 39 of 101 patients; P = 0.029). Patients with episodes of myocardial ischemia were more likely to die in the next 2 yr (P = 0.025). CONCLUSIONS: Perioperative administration of atenolol for 1 week to patients at high risk for coronary artery disease significantly reduces the incidence of postoperative myocardial ischemia. Reductions in perioperative myocardial ischemia are associated with reductions in the risk for death at 2 yr.

Adrenergic beta-Antagonists↗
PubMed1997

Apolipoprotein E phenotype and cognitive decline in a prospective study of elderly community women.

OBJECTIVE: To determine whether apolipoprotein E (Apo E) phenotype is associated with cognitive decline in community-dwelling nondemented elderly women. DESIGN: Prospective cohort study. SETTING: A university-affiliated clinic near Pittsburgh, Pa. PATIENTS: A total of 1750 nondemented community-dwelling women, aged 65 years and older, who were enrolled in the Study of Osteoporotic Fractures. MAIN OUTCOME MEASURES: The women completed a baseline interview and performed 3 cognitive tests: the modified Mini-Mental State Examination, Trials B, and Digit Symbol. Serum samples were obtained for Apo E typing. Baseline cognitive scores and repeated scores approximately 6 years after study enrollment were compared in women with and without Apo E epsilon 4. Cognitive decline, defined as the worst 10th percentile change scores, was assessed for each test and by phenotype group. RESULTS: After adjustment for age, education, presence of severe tremor, and depression, baseline scores did not differ by Apo E epsilon 4 status except for lower scores on Trails B in the homozygous epsilon 4 group (mean score, 159.7 compared with 127.7 for the heterozygous epsilon 4 group and 125.4 for the no epsilon 4 group; P = .01). However, repeated test performance on follow-up examination was worse on all tests in those women with 1 or more epsilon 4. Reduction on the modified Mini-Mental State Examination was 0% for no epsilon 4 allele, 1.9% for 1 epsilon 4 allele, and 3.7% for 2 epsilon 4 alleles (P < .001); reduction on Digit Symbol was 6.2% for no epsilon 4 allele, 9.0% for 1 epsilon 4 allele, and 17.5% for 2 epsilon 4 alleles (P = .04); and reduction on Trials B was 5.9% for no epsilon 4 allele, 25.0% for 1 epsilon 4 allele, and 10.9% for 2 epsilon 4 alleles (P = .002). Women with at least 1 epsilon 4 had an odds ratio of 1.6 (95% confidence interval, 1.1-2.3) of having cognitive decline during the study period. CONCLUSION: Apolipoprotein E epsilon 4 is associated with cognitive decline in community-dwelling nondemented women.

Aged↗
PubMed1997

The clinical impact of echocardiography on antibiotic prophylaxis use in patients with suspected mitral valve prolapse.

PURPOSE: To determine the impact of echocardiography on the use of antibiotic prophylaxis in patients with suspected mitral valve prolapse (MVP). PATIENTS AND METHODS: We evaluated 147 consecutive patients who were referred for "rule out mitral valve prolapse" to a university hospital echocardiography laboratory. Chart review and phone contact were used to determine the demographic characteristics of the patients; past diagnosis of MVP, symptoms, and exam at referral; practice specialty of referring MD; echocardiographic findings; and change in prophylaxis usage as a result of the echocardiogram (ECHO). Prophylaxis was considered to be indicated if the echocardiogram demonstrated MVP with at least mild regurgitation or abnormal thickening of at least one mitral leaflet. RESULTS: Based on the ECHO a change in antibiotic prophylaxis was indicated in 20 of 147 (14%) patients including initiation of prophylaxis in 6, and discontinuation of prophylaxis in 14. However, only 4 of 20 patients (20%) actually changed their prophylaxis habits leading to an actual yield of 4 management changes per 131 ECHOs ordered (3%). This corresponded to 1 change in management per $36,250 in hospital and physician costs. Younger age, female gender, and presence of symptoms were associated with a benign ECHO. Indications for a change in management were not significantly different between physician specialities: 18% for generalists (internal medicine and family practice), 12% for cardiologists, and 7% for other specialists, P = 0.3. CONCLUSIONS: In patients referred for evaluation of MVP, echocardiography infrequently resulted in changes in antibiotic prophylaxis management and was associated with significant expense.

Adult↗
PubMed1993

Effects of thiazide diuretic therapy on bone mass, fractures, and falls. The Study of Osteoporotic Fractures Research Group.

OBJECTIVE: To determine the relation between the use of thiazide diuretics and bone mass, fractures, and falls in older women. DESIGN: Cross-sectional study of thiazide diuretics, bone mass, and prevalent vertebral deformities; cohort analysis of thiazide diuretics and nonspinal fractures and falls. SETTING: Four clinical centers located in Baltimore, Maryland; Minneapolis, Minnesota; Portland, Oregon; and the Monongahela Valley, Pennsylvania. PARTICIPANTS: A total of 9704 ambulatory, nonblack women who were 65 years or older. MEASUREMENTS: Information on thiazide use, demographic data, medical history, and anthropometric measurements were obtained by questionnaire, interview, and examination. Appendicular bone mass was measured by single-photon absorptiometry. Incident falls and fractures were ascertained every 4 months. RESULTS: Women using thiazide diuretics for more than 10 years had significantly higher bone mass than women who had never used thiazide diuretics (for example, 0.381 g/cm2 compared with 0.355 g/cm2 for the distal radius [P < 0.001]). Current users of thiazide diuretics had an incidence of falls (relative risk, 1.06; 95% CI, 0.90 to 1.25) that was similar to that of those who had never used these drugs. After adjusting for age, body weight, functional status, total calcium intake, duration of estrogen replacement therapy, and self-reported health status, we found that current users of thiazide diuretics who had taken these drugs for more than 10 years had a risk for nonspinal (relative risk, 0.99; CI, 0.81 to 1.20) and osteoporotic (relative risk, 0.98; CI, 0.79 to 1.22) fractures that was similar to that of women who had never used thiazides; however, thiazide users did have a lower risk for fractures of the hip (relative risk, 0.63; CI, 0.34 to 1.16) and wrist (relative risk, 0.66; CI, 0.40 to 1.08), neither of which was significant. CONCLUSIONS: Thiazide diuretics have no effect on a women's risk for falling or for experiencing nonspinal fractures. The trend toward a lower risk for hip and wrist fractures is consistent with findings in previous cohort studies but may reflect selection factors for the use of thiazide diuretics. A randomized trial is needed to determine the effect ot thiazide diuretics on the incidence of fractures.

Accidental Falls↗
PubMed1993

Bone density at various sites for prediction of hip fractures. The Study of Osteoporotic Fractures Research Group.

Women with low bone density in the radius or calcaneus are at increased risk of hip fracture. To see whether bone density of the hip measured by dual X-ray absorptiometry is a better predictor of hip fracture than measurements of other bones, we assessed bone density at several sites in 8134 women aged 65 years or more. 65 women had hip fractures during a mean follow-up of 1.8 years. Each SD decrease in femoral neck bone density increased the age-adjusted risk of hip fracture 2.6 times (95% CL 1.9, 3.6). Women with bone density in the lowest quartile had an 8.5-fold greater risk of hip fracture than those in the highest quartile. Bone density of the femoral neck was a better predictor than measurements of the spine (p < 0.0001), radius (p < 0.002), and moderately better than the calcaneus (p = 0.10). Low hip bone density is a stronger predictor of hip fracture than bone density at other sites. Efforts to prevent hip fractures should focus on women with low hip bone density.

Absorptiometry, Photon↗
PubMed1992

Axial and appendicular bone density predict fractures in older women.

To determine whether measurement of hip and spine bone mass by dual-energy x-ray absorptiometry (DEXA) predicts fractures in women and to compare the predictive value of DEXA with that of single-photon absorptiometry (SPA) of appendicular sites, we prospectively studied 8134 nonblack women age 65 years and older who had both DEXA and SPA measurements of bone mass. A total of 208 nonspine fractures, including 37 wrist fractures, occurred during the follow-up period, which averaged 0.7 years. The risk of fracture was inversely related to bone density at all measurement sites. After adjusting for age, the relative risks per decrease of 1 standard deviation in bone density for the occurrence of any fracture was 1.40 for measurement at the proximal femur (95% confidence interval 1.20-1.63) and 1.35 (1.15-1.58) for measurement at the spine. Results were similar for all regions of the proximal femur as well as SPA measurements at the calcaneus, distal radius, and proximal radius. None of these measurements was a significantly better predictor of fractures than the others. Furthermore, measurement of the distal radius was not a better predictor of wrist fracture (relative risk 1.64: 95% CI 1.13-2.37) than other sites, such as the lumbar spine (RR 1.56; CI 1.07-2.26), the femoral neck (RR 1.65; CI 1.12-2.41), or the calcaneus (RR 1.83; CI 1.26-2.64). We conclude that the inverse relationship between bone mass and risk of fracture in older women is similar for absorptiometric measurements made at the hip, spine, and appendicular sites.

Absorptiometry, Photon↗
PubMed1989

The epidemiology of pulmonary function and COPD mortality in the multiple risk factor intervention trial.

The potential determinants of the changes in chronic obstructive pulmonary disease (COPD) mortality were evaluated using both the Multiple Risk Factor Intervention Trial (MRFIT) screenees, the longitudinal analysis of the participants, and the differences in special intervention (SI) and usual care (UC) groups. COPD was the underlying cause for only one third of all death certificates listing COPD. Small changes in classification will have a major impact on reported COPD death rates. Cigarette smoking is clearly the primary determinant of COPD mortality. Decreased pulmonary function is an independent risk factor for coronary heart disease (CHD) mortality. Smoking cessation results in a slower rate of decline in pulmonary function over time, especially among heavy smokers. Careful evaluation of smoking cessation, including repeat chemical measures, suggest that the percentage of long-term quitters, especially among heavy smokers has been overestimated. The low percentage of quitters substantially reduced the power to detect an intervention effect. The increased cigarette smoking among recent older cohorts, and failure to substantially reduce smoking, especially among heavy smokers, may be an important factor accounting for the failure to note a decline in COPD mortality among older persons.

Adult↗
PubMed1988

Evaluating outcomes of pregnancy in diabetic women. Epidemiologic considerations and recommended indicators.

Many programs have been applied in various settings to reduce adverse outcomes of pregnancy in women with diabetes. Efforts to standardize criteria and methods for evaluating these programs are relatively recent. Without such standardization, evaluation of the impact of many programs and comparisons among programs have not been possible. We review the suitability of available data sources for monitoring adverse outcomes of pregnancy in women with diabetes in light of epidemiological considerations relevant to selection of indicators of program impact. This article is intended to be a resource to help evaluate in a standardized fashion the impact of programs at a regional, state, or local level. We conclude that primary data (information collected by programs themselves) collected in a standardized manner are necessary for evaluation of programs for diabetes in pregnancy. Secondary data sources alone are of limited value for monitoring outcomes because of underreporting of maternal diabetes, especially in the absence of identified complications. Ultimately, the ability to rigorously assess the impact of efforts to improve outcomes of diabetes in pregnancy may depend on the creation of comprehensive statewide systems to identify women of childbearing age who have diabetes.

Congenital Abnormalities↗
PubMed1988

Perioperative myocardial ischemia: importance of the preoperative ischemic pattern.

Previous studies investigating the incidence of myocardial ischemia in patients undergoing coronary-artery bypass grafting (CABG) surgery have not considered the potential significance of the preoperative ischemic pattern in the development of intra- and postoperative myocardial ischemia and infarction. Accordingly, the authors compared the frequency and severity of pre-, intra-, and postoperative ischemic episodes (ST-segment depression greater than or equal to 0.1 mV or elevation greater than or equal to 0.2 mV) in 50 men with severe coronary artery disease scheduled for elective CABG. All subjects were monitored by continuous electrocardiography (ECG) (Holter monitor) for 2 preoperative days, intraoperatively, and 2 postoperative days (total monitoring time = 4,363 h). Routine anti-anginal medications were continued until the morning of surgery, and the anesthetic management of the patient was not controlled. During the preoperative period, 42% of the patients had ECG ischemic episodes, 87% of which were clinically silent. Only 18% developed intraoperative ischemia. Postoperatively, the incidence increased to 40%. The number of ischemic episodes/hour (epis/h) of monitoring among the three monitoring periods was similar (0.09 +/- 0.12 epis/h preoperatively, 0.11 +/- 0.20 epis/h intraoperatively, and 0.05 +/- 0.08 epis/h postoperatively; P = NS). The median duration of ischemic episodes was similar pre- and intraoperatively (16 vs. 18.5 min, P = NS), but greater postoperatively (41 min, P less than 0.05). Seventy-six per cent of the perioperative ECG ischemia occurred without acute change (+/- 20% of control) in blood pressure or heart rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Intraoperative myocardial ischemia: localization by continuous 12-lead electrocardiography.

Based primarily on results obtained during exercise treadmill testing, electrocardiographic (ECG) leads II and V5 are the suggested optimal leads for detecting intraoperative myocardial ischemia. However, these recommendations have not been validated in this setting using all 12 ECG leads. Accordingly, the authors studied 105 patients with known or suspected coronary artery disease (CAD) undergoing noncardiac surgery with general anesthesia by continuously recording the 12-lead ECG intraoperatively in all patients. The average duration of monitoring was 8.2 +/- 2.7 h (mean +/- SD). Ischemic episodes (i.e., greater than or equal to 1-mm horizontal or downsloping ST depression, greater than or equal to 1.5-mm slowly upsloping ST depression or greater than or equal to 1.5-mm ST elevation in a non-Q wave lead) occurred in 25 patients (24%). Out of 51 ischemic episodes, 45 involved ST depression alone, and the remaining six involved both ST depression and elevation. ST segment changes occurred in a single lead only in 14 episodes, while multiple leads were involved in 37 episodes. Lead sensitivity was estimated assuming that all ST segment changes were true positive responses. Sensitivity using a single lead was greatest in V5 (75%) and V4 (61%), and intermediate in II, V3, and V6 (33%, 24%, and 37%, respectively). The remaining seven leads demonstrated very low sensitivity (2-14%) or exhibited no ischemic changes (I and a VL). Combining leads V4 and V5 increased sensitivity to 90%, while the standard clinical combination, II and V5, was only 80% sensitive. Sensitivity increased to 96% by combining II, V4, and V5. The further addition of V2 and V3 (five leads) increased sensitivity to 100%. This study confirms previous recommendations for the routine use of a V5 lead (either uni- or bipolar) in all patients at risk for ischemia. V4 is more sensitive than lead II, and should be considered as a second choice. However, lead II, superior for detection of atrial dysrhythmias, is more easily obtained with conventional monitors. The use of all three would appear to be the optimal arrangement for most clinical needs, and is recommended if the clinician has the capability.

Aged↗
PubMed1986

The economic costs of the health effects of smoking, 1984.

The impact of cigarette smoking on morbidity and mortality in the United States is well known. Economic consequences of these health effects--expenditures for medical care and the value of productive output lost--have been estimated in many ways. This original prevalence-based analysis of attributable risks indicates a staggering $54 billion cost to the nation. Concern over such misallocation of resources to harmful uses is demonstrably justified.

Adolescent↗