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V Hasselblad

Publications and source records attributed to V Hasselblad.

At least 37 records · Page 2Linked to original sources
PubMed2000

Does primary intraocular lens implantation prevent "aphakic" glaucoma in children?

PURPOSE: Open-angle glaucoma may develop after surgery for congenital or developmental cataract with an incidence ranging from 3% to 41%. The pathogenesis of "aphakic" (open-angle) glaucoma remains unknown. Despite numerous reported clinical series (>1000 eyes), we are unaware of any reported case of open-angle glaucoma after primary intraocular lens (IOL) implantation for congenital or developmental cataract. We decided to test the hypothesis that primary posterior chamber IOL implantation might decrease the incidence of open-angle glaucoma in children. METHODS: Pseudophakic eyes were collected from surgeons who contributed data to a refractive study and who monitored intraocular pressure on a regular basis. IOL implantation was commonly performed in eyes with a corneal diameter >10 mm. Comparable primary data on aphakic eyes were included from 2 published studies on aphakic glaucoma, which included corneal diameters and the patient's age at surgery. Glaucoma-free survival estimates for each cohort were estimated. RESULTS: Only 1 case of glaucoma was found among 377 eyes with primary pseudophakia (mean age of patient, 5.1 +/- 4.7 years; mean follow-up, 3.9 +/- 2.7 years). There were 14 eyes (11.3%) with glaucoma among 124 aphakic eyes (mean age of patient, 2.7 +/- 2.6 years; mean follow-up time, 7.2 +/- 3.9 years). CONCLUSIONS: We report a decreased incidence of open-angle glaucoma among eyes rendered primarily pseudophakic compared with those that remained aphakic after cataract surgery. We propose 2 theories on the possible mechanism of reduction in the incidence of glaucoma in pseudophakic eyes.

Adolescent↗
PubMed2000

Reply

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Journal Article↗
PubMed1999

Clinical outcomes of bivalirudin for ischemic heart disease.

BACKGROUND: Current treatment strategies for percutaneous coronary revascularization and acute coronary syndromes incorporate thrombin inhibition with either unfractionated or fractionated heparin. The peptide bivalirudin (Hirulog) is a direct thrombin inhibitor whose pharmacological properties differ from those of heparin. We conducted a systematic overview (meta-analysis) to assess the effect of bivalirudin on 4 end points: death, myocardial infarction, major hemorrhage, and the composite of death or infarction. METHODS AND RESULTS: Six trials (5674 patients) represent the randomized, controlled bivalirudin experience, including 4603 patients undergoing elective percutaneous coronary revascularization and 1071 patients with acute coronary syndromes. ORs for the 4 clinical end points were calculated for each trial. Four trials (4973 patients) that compared bivalirudin with heparin were combined with the use of a random-effects model. In these trials, bivalirudin was associated with a significant reduction in the composite of death or infarction (OR 0.73, 95% CI 0.57 to 0.95; P=0.02) at 30 to 50 days, or 14 fewer events per 1000 patients so treated. There also was a significant reduction in major hemorrhage for the same trials (OR 0.41, 95% CI 0. 32 to 0.52; P<0.001, or 58 fewer events per 1000 patients so treated). A similar analysis combined 2 dose-ranging trials (701 patients) that compared therapeutic (activated partial thromboplastin time more than twice the control time) with subtherapeutic bivalirudin anticoagulation (activated partial thromboplastin time less than twice the control time). CONCLUSIONS: Bivalirudin is at least as effective as heparin, with clearly superior safety. Thus, it provides an unprecedented net clinical benefit over heparin in patients with ischemic heart disease.

Anticoagulants↗
PubMed1999

Reduction in heart failure events by the addition of a clinical pharmacist to the heart failure management team: results of the Pharmacist in Heart Failure Assessment Recommendation and Monitoring (PHARM) Study.

BACKGROUND: The multidisciplinary approach to managing heart failure has been shown to improve outcomes. The role of a clinical pharmacist in treating heart failure has not been evaluated. METHODS: One hundred eighty-one patients with heart failure and left ventricular dysfunction (ejection fraction <45) undergoing evaluation in clinic were randomized to an intervention or a control group. Patients in the intervention group received clinical pharmacist evaluation, which included medication evaluation, therapeutic recommendations to the attending physician, patient education, and follow-up telemonitoring. The control group received usual care. The primary end point was combined all-cause mortality and heart failure clinical events. All clinical events were adjudicated by a blinded end point committee. RESULTS: Baseline characteristics were similar except for slightly higher age in the intervention group. Median follow-up was 6 months. All-cause mortality and heart failure events were significantly lower in the intervention group compared with the control group (4 vs 16; P= .005). In addition, patients in the intervention group received higher angiotensin-converting enzyme inhibitor doses as reflected by the median fraction of target reached (25th and 75th percentiles), 1.0 (0.5 and 1) and 0.5 (0.1875 and 1) in the intervention and control groups, respectively (P<.001). The use of other vasodilators in angiotensin-converting enzyme inhibitor-intolerant patients was higher in the intervention group (75% vs 26%; P= .02). CONCLUSIONS: Outcomes in heart failure can be improved with a clinical pharmacist as a member of the multidisciplinary heart failure team. This observation may be due to higher doses of angiotensin-converting enzyme inhibitors and/or closer follow-up.

Aged↗
PubMed1999

Hormone replacement therapy and the risk of colorectal cancer: a meta-analysis.

OBJECTIVE: To review systematically the association between hormone replacement therapy (HRT) and the risk of developing or dying from colorectal cancer. DATA SOURCES: We searched the English-language literature using MEDLINE, Current Contents, CancerLit, and bibliographies of selected studies. METHODS OF STUDY SELECTION: We included studies that specifically addressed the association of HRT with colorectal cancer, had adequate controls, and had retrievable risk estimates. We excluded letters, reviews, and multiple publications of the same data. TABULATION, INTEGRATION, AND RESULTS: Studies were evaluated independently by two of the authors. The exposures of interest were ever, recent, or former use of HRT, and the main outcome measures were colon and rectal cancer incidence and mortality. To reduce the risk of a "healthy estrogen user" bias, we defined recent HRT use as either at time of assessment or within the previous year. The most adjusted risk estimates were extracted. We used a random-effects model to calculate summary relative risks (RRs) and confidence intervals (CIs). Recent use of HRT was associated with a 33% reduction in the risk of colon cancer (RR = 0.67; 95% CI 0.59, 0.77). Protection was limited to recent users; the risk of colon cancer with ever use of HRT was 0.92 (95% CI 0.79, 1.08). Duration of use was not significant. Three studies addressed the risk of fatal colon cancer; the summary RR for death from colon cancer in HRT users was 0.72 (95% CI 0.64, 0.81) compared with nonusers. Rectal cancer incidence was not associated with HRT. CONCLUSION: The risk of colon cancer may be decreased among recent postmenopausal HRT users. Although data are limited, the risk of fatal colon cancer also may be lower in HRT users.

Colorectal Neoplasms↗
PubMed1999

Assessment of human exposure to ambient particulate matter.

Recent epidemiological studies have consistently shown that the acute mortality effects of high concentrations of ambient particulate matter (PM), documented in historic air pollution episodes, may also be occurring at the low to moderate concentrations of ambient PM found in modern urban areas. In London in December 1952, the unexpected deaths due to PM exposure could be identified and counted as integers by the coroners. In modern times, the PM-related deaths cannot be as readily identified, and they can only be inferred as fractional average daily increases in mortality rates using sophisticated statistical filtering and analyses of the air quality and mortality data. The causality of the relationship between exposure to ambient PM and acute mortality at these lower modern PM concentrations has been questioned because of a perception that there is little significant correlation in time between the ambient PM concentrations and measured personal exposure to PM from all sources (ambient PM plus indoor-generated PM). This article shows that the critical factor supporting the plausibility of a linear PM mortality relationship is the expected high correlation in time of people's exposure to PM of ambient origin with measured ambient PM concentrations, as used in the epidemiological time series studies. The presence of indoor and personal sources of PM masks this underlying relationship, leading to confusion in the scientific literature about the strong underlying temporal relationship between personal exposure to PM of ambient origin and ambient PM concentration. The authors show that the sources of PM of non-ambient origin operate independently of the ambient PM concentrations, so that the mortality effect of non-ambient PM, if any, must be independent of the effects of the ambient PM exposures.

Air Pollutants, Occupational↗
PubMed1999

Patient Outcomes Research Teams: contribution to outcomes and effectiveness research.

This paper describes the key methodological and substantive findings of Patient Outcomes Research Teams, the first outcomes and effectiveness research centers funded by the Agency for Health Care Policy and Research. Patient Outcomes Research Teams contributed to our increased understanding of how to perform meta analysis on nontrial data, use administrative data to characterize patterns of care, develop general and disease-specific outcome measures, and disseminate important outcome information to patients and physicians to reduce practice variation. Patient Outcomes Research Teams also influenced the development of outcomes measurement in the private sector.

Health Services Research↗
PubMed1999

Relative effectiveness and cost-effectiveness of methods of androgen suppression in the treatment of advanced prostate cancer.

OBJECTIVES: With 184,500 new cases and 39,200 deaths anticipated in 1998, prostate cancer is second only to lung cancer in cancer mortality for men. This report is a systematic review of the evidence from randomized controlled trials on the relative effectiveness of alternative strategies for androgen suppression as treatment of advanced prostate cancer. Three key issues are addressed: (1) the relative effectiveness of the available methods for monotherapy (orchiectomy, luteinizing hormone-releasing hormone [LHRH] agonists, and antiandrogens), (2) the effectiveness of combined androgen blockade compared to monotherapy, and (3) the effectiveness of immediate androgen suppression compared to androgen suppression deferred until clinical progression. Outcomes of interest are overall, cancer-specific, and progression-free survival; time to treatment failure; adverse effects; and quality of life. Two supplementary analyses were conducted for each key question: (1) meta-analysis of overall survival at 2 years (questions 1 and 2) and 5 years (questions 2 and 3), and (2) cost-effectiveness analysis. SEARCH STRATEGY: The MEDLINE, CANCERLIT, and EMBASE databases were searched from 1966 to March 1998, and Current Contents to August 24, 1998, for the terms: leuprolide (Lupron); goserelin (Zoladex); buserelin (Suprefact); flutamide (Eulexin); nilutamide (Anandron, Nilandron); bicalutamide (Casodex); cyproterone acetate (Androcur); diethylstilbestrol (DES); and orchiectomy (castration, orchidectomy). The search was then limited to human studies indexed under the MeSH term "prostatic neoplasms" and by the UK Cochrane Center search strategy for randomized controlled trials. Total yield was 1,477 references. SELECTION CRITERIA: We Reports of efficacy outcomes were limited to randomized controlled trials. Phase II studies that reported on withdrawals from therapy and all studies reporting on quality of life were also included. DATA COLLECTION AND ANALYSIS: The systematic review used a prospectively designed protocol conducted by two independent reviewers, with disagreements resolved by consensus. The meta-analysis combined data on overall survival using a random effects model. The cost-effectiveness analysis used a decision analysis model of advanced prostate cancer with health states and transitions derived from the literature and estimates of effectiveness derived from the meta-analysis. The cost-effectiveness analysis is conducted from a societal perspective, consistent with the guidelines of the U.S. Public Health Service Panel on Cost-Effectiveness in Health and Medicine. MAIN RESULTS: Survival after treatment with an LHRH agonist is equivalent to survival after orchiectomy. The available LHRH agonists are equally effective, and no LHRH agonist is superior to the other when adverse effects are considered. Survival may be somewhat lower with use of a nonsteroidal antiandrogen. There is no statistically significant difference in survival at 2 years between patients treated with combined androgen blockade or monotherapy. Meta-analysis of the limited data available shows a statistically significant difference in survival at 5 years that favors combined androgen blockade. However, the magnitude of this difference is of questionable clinical significance. For the subgroup of patients with good prognosis, there is no statistically significant difference in survival. Adverse effects leading to withdrawal from therapy occurred more often with combined androgen blockade. No evidence is yet available from randomized controlled trials of androgen suppression initiated at prostate-specific antigen (PSA) rise after definitive therapy for clinically localized disease. For patients who are newly diagnosed with locally advanced or asymptomatic metastatic disease, the evidence is insufficient to determine whether primary androgen suppression initiated at diagnosis improves outcomes. (ABSTRACT TRUNCATED)

Androgen Antagonists↗
PubMed1998

Hormone replacement therapy and the risk of colorectal cancer: a meta-analysis.

Objective: To review systematically the association between hormone replacement therapy and colorectal cancer incidence and mortality.Methods: We conducted a literature search of English-language studies using MEDLINE, Current Contents, CancerLit, and bibliographies of selected studies. The exposures of interest were ever, recent, or former use of hormone replacement therapy (HRT) and the main outcome measures were colon and rectal cancer incidence and mortality. To reduce the risk of a "healthy estrogen user" bias, we defined recent HRT usage as use either at time of assessment or within the previous year. Studies were evaluated independently by two of the authors. We included studies with adequate controls and retrievable risk estimates. We excluded letters, abstracts, and multiple publications of the same data. The most adjusted risk estimates were extracted. We used the empirical Bayes method, a random-effects model, to calculate summary relative risks (RR) and confidence intervals (CI).Results: Recent use of HRT was associated with a significantly decreased risk of colon cancer (RR = 0.69, 95% CI 0.58-0.81). Protection was limited to recent users; the risk of colon cancer with any use of HRT was 0.94 (95% CI 0.79-1.12). Duration of use was not significant. Three studies addressed colon cancer mortality; the summary RR for death from colon cancer in HRT users was 0.72 (95% CI 0.64-0.81). Rectal cancer incidence and mortality were not associated with HRT use.Conclusion: The risk of colon cancer may be decreased among recent postmenopausal HRT users. Although data are limited, the risk of death from colon cancer may also be lower in HRT users.

Journal Article↗
PubMed1998

Distribution of transferrin saturations in the African-American population.

To determine if transferrin saturations in African Americans may reflect the presence of a gene that influences iron metabolism, we analyzed the distribution of these values in 808 African Americans from the second National Health and Nutrition Survey. We tested for a mixture of three normal distributions consistent with population genetics for a major locus effect in which the proportion of normal homozygotes is p2; of heterozygotes, 2pq; of affected homozygotes, q2; and in which p+q = 1. Three subpopulations based on transferrin saturation were present (P < .0001) and the fit to a mixture of three normal distributions was good (P = .2). A proportion of .009 was included in a subpopulation with a mean +/- standard deviation transferrin saturation of 63.4% +/- 5.7% (postulated homozygotes for a gene that influences iron metabolism), while a proportion of .136 had an intermediate saturation of 38.0% +/- 5.7% (postulated heterozygotes) and .856 a saturation of 24.6% +/- 5.7% (postulated normal homozygotes). These proportions were consistent with population genetics because the sum of the square roots of the proportions with the lowest mean transferrin saturation (P = .925) and the highest (q = 0.093) was approximately 1 (1.018). The results are consistent with the presence in African Americans of a common locus that influences iron metabolism.

Adult↗
PubMed1998

Is optimal angiotensin-converting enzyme inhibitor dosing neglected in elderly patients with heart failure?

BACKGROUND: The benefit of angiotensin-converting enzyme (ACE) inhibitors on mortality in heart failure has been proved in randomized controlled trials. METHODS: We prospectively evaluated the prescribing of ACE inhibitors and the prescribing of target ACE inhibitor doses in 43 ambulatory patients with heart failure to identify differences in ACE inhibitor utilization among elderly and nonelderly patients. The prescribed ACE inhibitor dose and other variables were assessed by direct patient interview and information contained in the medical record. Telephone calls were conducted at 3 months to identify the occurrence of clinical events. RESULTS: Fewer elderly patients were prescribed target ACE inhibitor doses compared with nonelderly patients (21.4% vs 68.8%; p = 0.0136). Elderly patients were more likely to experience an event than nonelderly patients (11 vs 4; p = 0.0074). Elderly patients not receiving target ACE inhibitor doses demonstrated a trend toward more events than elderly patients who were at target doses. CONCLUSION: The data suggest that this group of elderly patients with heart failure who received lower ACE inhibitor doses appeared to be at higher risk for clinical events.

Aged↗
PubMed1998

Failure of the mandatory domestic violence reporting law to increase medical facility referral to police.

STUDY OBJECTIVE: To assess the effect of California's 1994 mandatory domestic violence reporting law on Los Angeles Sheriff's Department dispatches to medical facilities for domestic violence incidents. METHODS: This ecological time-trend study analyzed data from the Los Angeles Sheriff's Department for the period January 1, 1993, to December 31, 1995. All 26,051 dispatches for domestic violence offenses during the study period were analyzed. The outcome measures were changes in biweekly department dispatches for domestic violence offenses resulting from the implementation of the mandatory domestic violence reporting law adjusted for seasonal variation and the Simpson/Goldman murders. RESULTS: The percentage of biweekly dispatches to medical facilities for domestic violence offenses did not increase in response to the law (beta = -.0072, P = .095). Total domestic violence dispatches increased significantly after the Simpson/Goldman murders but not after passage of the law (beta = 82.7, P < .0001 versus beta = -10.1, P = .2205). CONCLUSION: The mandatory domestic violence reporting law in California did not increase medical personnel reporting of domestic violence situations to the Sheriff's Department during the 2 years after its implementation.

Adult↗
PubMed1998

The Agency for Health Care Policy and Research Smoking Cessation Clinical Practice Guideline. Findings and implications for psychologists.

Smoking is the leading cause of preventable morbidity and mortality in the United States, and the health benefits of quitting smoking are substantial. Nevertheless, over 25% of American adults (48 million individuals) continue to smoke, and the vast majority of quit attempts are unsuccessful. The Agency for Health Care Policy and Research recently addressed the smoking problem by conducting a 2-year research project that was published as the Smoking Cessation Clinical Practice Guideline (Fiore et al., 1996). This article reviews methods, analyses, and results from the Guideline project, and highlights major Guideline recommendations. Guideline findings and recommendations are discussed with respect to their implications for psychology.

Adult↗
PubMed1997

Cost-effectiveness of the clinical practice recommendations in the AHCPR guideline for smoking cessation. Agency for Health Care Policy and Research.

CONTEXT: The Agency for Health Care Policy and Research (AHCPR) published the Smoking Cessation: Clinical Practice Guideline in 1996. Based on the results of meta-analyses and expert opinion, the guideline identifies efficacious interventions for primary care clinicians and smoking cessation specialty providers. OBJECTIVE: To determine the cost-effectiveness of clinical recommendations in AHCPR's guideline. DESIGN: The guideline's 15 recommended smoking cessation interventions were analyzed to determine their relative cost-effectiveness. Then, using decision probabilities, the interventions were combined into a global model of the guideline's overall cost-effectiveness. PATIENTS: The analysis assumes that primary care clinicians screen all presenting adults for smoking status and advise and motivate all smokers to quit during the course of a routine office visit or hospitalization. Smoking cessation interventions are provided to 75% of US smokers 18 years and older who are assumed to be willing to make a quit attempt during a year's time. INTERVENTION: Three counseling interventions for primary care clinicians and 2 counseling interventions for smoking cessation specialists were modeled with and without transdermal nicotine and nicotine gum. MAIN OUTCOME MEASURE: Cost (1995 dollars) per life-year or quality-adjusted life-year (QALY) saved, at a discount of 3%. RESULTS: The guideline would cost $6.3 billion to implement in its first year. As a result, society could expect to gain 1.7 million new quitters at an average cost of $3779 per quitter, $2587 per life-year saved, and $1915 for every QALY saved. Costs per QALY saved ranged from $1108 to $4542, with more intensive interventions being more cost-effective. Group intensive cessation counseling exhibited the lowest cost per QALY saved, but only 5% of smokers appear willing to undertake this type of intervention. CONCLUSIONS: Compared with other preventive interventions, smoking cessation is extremely cost-effective. The more intensive the intervention, the lower the cost per QALY saved, which suggests that greater spending on interventions yields more net benefit. While all these clinically delivered interventions seem a reasonable societal investment, those involving more intensive counseling and the nicotine patch as adjuvant therapy are particularly meritorious.

Adult↗
PubMed1997

The Stroke Prevention Policy Model: linking evidence and clinical decisions.

Simulation models that support decision and cost-effectiveness analysis can further the goals of evidence-based medicine by facilitating the synthesis of information from several sources into a single comprehensive structure. The Stroke Prevention Policy Model (SPPM) performs this function for the clinical and policy questions that surround stroke prevention. This paper first describes the basic structure and functions of the SPPM, concentrating on the role of large databases (broadly defined as any database that contains many patients, regardless of study design) in providing the SPPM inputs. Next, recognizing that the use of modeling continues to be a source of some controversy in the medical community, it discusses the philosophical underpinnings of the SPPM. Finally, it discusses conclusions in the context of both stroke prevention and other complex medical decisions. We conclude that despite the difficulties in developing comprehensive models (for example, the length and complexity of model development and validation processes, the proprietary nature of data sources, and the necessity for developing new software), the benefits of such models exceed the costs of continuing to rely on more conventional methods. Although they should not replace the clinician in decision making, comprehensive models based on the best available evidence from large databases can support decision making in medicine.

Cerebrovascular Disorders↗
PubMed1997

Pediatric Vesicoureteral Reflux Guidelines Panel summary report on the management of primary vesicoureteral reflux in children.

PURPOSE: The American Urological Association convened the Pediatric Vesicoureteral Reflux Guidelines Panel to analyze the literature regarding available methods for treating vesicoureteral reflux diagnosed following a urinary tract infection in children and to make practice policy recommendations based on the treatment outcomes data insofar as the data permit. MATERIALS AND METHODS: The panel searched the MEDLINE data base for all articles from 1965 to 1994 on vesicoureteral reflux and systematically analyzed outcomes data for 7 treatment alternatives: 1) intermittent antibiotic therapy, 2) bladder training, 3) continuous antibiotic prophylaxis, 4) antibiotic prophylaxis and bladder training, 5) antibiotic prophylaxis, anticholinergics and bladder training, 6) open surgical repair and 7) endoscopic repair. Key outcomes identified were probability of reflux resolution, likelihood of developing pyelonephritis and scarring, and possibility of complications of medical and surgical treatment. RESULTS: Available outcomes data on the various treatment alternatives were summarized in tabular form and graphically, and the relative probabilities of possible outcomes were compared for each alternative. Treatment recommendations were based on scientific evidence and expert opinion. The panel concluded that only a few recommendations can be derived purely from scientific evidence of a beneficial effect on health outcomes. CONCLUSIONS: For most children the panel recommended continuous antibiotic prophylaxis as initial treatment. Surgery was recommended for children with persistent reflux and other indications, as specified in the document.

Child↗