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Peter Jüni

Publications and source records attributed to Peter Jüni.

At least 19 recordsLinked to original sources
PubMed2006

Accuracy of B-type natriuretic peptide tests to exclude congestive heart failure: systematic review of test accuracy studies.

BACKGROUND: Congestive heart failure (CHF) is a major public health problem. The use of B-type natriuretic peptide (BNP) tests shows promising diagnostic accuracy. Herein, we summarize the evidence on the accuracy of BNP tests in the diagnosis of CHF and compare the performance of rapid enzyme-linked immunosorbent assay (ELISA) and standard radioimmunosorbent assay (RIA) tests. METHODS: We searched electronic databases and the reference lists of included studies, and we contacted experts. Data were extracted on the study population, the type of test used, and methods. Receiver operating characteristic (ROC) plots and summary ROC curves were produced and negative likelihood ratios pooled. Random-effect meta-analysis and metaregression were used to combine data and explore sources of between-study heterogeneity. RESULTS: Nineteen studies describing 22 patient populations (9 ELISA and 13 RIA) and 9093 patients were included. The diagnosis of CHF was verified by echocardiography, radionuclide scan, or echocardiography combined with clinical criteria. The pooled negative likelihood ratio overall from random-effect meta-analysis was 0.18 (95% confidence interval [CI], 0.13-0.23). It was lower for the ELISA test (0.12; 95% CI, 0.09-0.16) than for the RIA test (0.23; 95% CI, 0.16-0.32). For a pretest probability of 20%, which is typical for patients with suspected CHF in primary care, a negative result of the ELISA test would produce a posttest probability of 2.9%; a negative RIA test, a posttest probability of 5.4%. CONCLUSIONS: The use of BNP tests to rule out CHF in primary care settings could reduce demand for echocardiography. The advantages of rapid ELISA tests need to be balanced against their higher cost.

Biomarkers↗
PubMed2006

Glycemic control and macrovascular disease in types 1 and 2 diabetes mellitus: Meta-analysis of randomized trials.

BACKGROUND: Uncertainty persists concerning the effect of improved long-term glycemic control on macrovascular disease in diabetes mellitus (DM). METHODS: We performed a systematic review and meta-analysis of randomized controlled trials comparing interventions to improve glycemic control with conventional treatment in type 1 and type 2 diabetes. Outcomes included the incidence rate ratios for any macrovascular event, cardiac events, stroke, and peripheral arterial disease, and the number needed to treat intensively during 10 years to prevent one macrovascular event. RESULTS: The analysis was based on 8 randomized comparisons including 1800 patients with type 1 DM (134 macrovascular events, 40 cardiac events, 88 peripheral vascular events, 6 cerebrovascular events, 11293 person-years of follow-up) and 6 comparisons including 4472 patients with type 2 DM (1587 macrovascular events, 1197 cardiac events, 87 peripheral vascular events, 303 cerebrovascular events, 43607 person-years). Combined incidence rate ratios for any macrovascular event were 0.38 (95% CI 0.26-0.56) in type 1 and 0.81 (0.73-0.91) in type 2 DM. In type 1 DM, effect was mainly based on reduction of cardiac and peripheral vascular events and, in type 2 DM, due to reductions in stroke and peripheral vascular events. Effects appear to be particularly important in younger patients with shorter duration of diabetes. CONCLUSIONS: Our data suggest that attempts to improve glycemic control reduce the incidence of macrovascular events both in type 1 and type 2 DM. In absolute terms, benefits are comparable, although effects on specific manifestations of macrovascular disease differ.

Adult↗
PubMed2006

Osteoarthritis: rational approach to treating the individual.

Osteoarthritis (OA) is the most common form of joint disease and the leading cause of pain and physical disability in older people. Risk factors for incidence and progression of osteoarthritis vary considerably according to the type of joint. Disease assessment is difficult and the relationship between the radiographic severity of joint damage and the incidence and severity of pain is only modest. Psychosocial and socio-economic factors play an important role. This chapter will discuss four main guiding principles to the management of OA: (1) to avoid overtreating people with mild symptoms; (2) to attempt to avoid doing more harm than good ('primum non nocere'); (3) to base patient management on the severity of pain, disability and distress, and not on the severity of joint damage or radiographic change; and (4) to start with advice about simple measures that patients can take to help themselves, and only progress to interventions that require supervision or specialist knowledge if simple measures fail. Effect sizes derived from meta-analyses of large randomized trials in OA are only small to moderate for most therapeutic interventions, but they are still valuable for patients and clinically relevant for physicians. Joint replacement may be the only option with a large effect size, but is only appropriate for the relatively small number of people with OA who have advanced disease and severe symptoms. The key to successful management involves patient and health professionals working together to develop optimal treatment strategies for the individual.

Combined Modality Therapy↗
PubMed2006

Sleepless night, the moon is bright: longitudinal study of lunar phase and sleep.

Popular belief holds that the lunar cycle affects human physiology, behaviour and health. We examined the influence of moon phase on sleep duration in a secondary analysis of a feasibility study of mobile telephone base stations and sleep quality. We studied 31 volunteers (18 women and 13 men, mean age 50 years) from a suburban area of Switzerland longitudinally over 6 weeks, including two full moons. Subjective sleep duration was calculated from sleep diary data. Data were analysed using multiple linear regression models with random effects. Mean sleep duration was 6 h 49 min. Subjective sleep duration varied with the lunar cycle, from 6 h 41 min at full moon to 7 h 00 min at new moon (P < 0.001). Average sleep duration was shortened by 68 min during the week compared with weekends (P < 0.001). Men slept 17 min longer than women (P < 0.001) and sleep duration decreased with age (P < 0.001). There was also evidence that rating of fatigue in the morning was associated with moon phase, with more tiredness (P = 0.027) at full moon. The study was designed for other purposes and the association between lunar cycle and sleep duration will need to be confirmed in further studies.

Adolescent↗
PubMed2005

Sirolimus-eluting and paclitaxel-eluting stents for coronary revascularization.

BACKGROUND: Sirolimus-eluting stents and paclitaxel-eluting stents, as compared with bare-metal stents, reduce the risk of restenosis. It is unclear whether there are differences in safety and efficacy between the two types of drug-eluting stents. METHODS: We conducted a randomized, controlled, single-blind trial comparing sirolimus-eluting stents with paclitaxel-eluting stents in 1012 patients undergoing percutaneous coronary intervention. The primary end point was a composite of major adverse cardiac events (death from cardiac causes, myocardial infarction, and ischemia-driven revascularization of the target lesion) by nine months. Follow-up angiography was completed in 540 of 1012 patients (53.4 percent). RESULTS: The two groups had similar baseline clinical and angiographic characteristics. The rate of major adverse cardiac events at nine months was 6.2 percent in the sirolimus-stent group and 10.8 percent in the paclitaxel-stent group (hazard ratio, 0.56; 95 percent confidence interval, 0.36 to 0.86; P=0.009). The difference was driven by a lower rate of target-lesion revascularization in the sirolimus-stent group than in the paclitaxel-stent group (4.8 percent vs. 8.3 percent; hazard ratio, 0.56; 95 percent confidence interval, 0.34 to 0.93; P=0.03). Rates of death from cardiac causes were 0.6 percent in the sirolimus-stent group and 1.6 percent in the paclitaxel-stent group (P=0.15); the rates of myocardial infarction were 2.8 percent and 3.5 percent, respectively (P=0.49); and the rates of angiographic restenosis were 6.6 percent and 11.7 percent, respectively (P=0.02). CONCLUSIONS: As compared with paclitaxel-eluting stents, the use of sirolimus-eluting stents results in fewer major adverse cardiac events, primarily by decreasing the rates of clinical and angiographic restenosis.

Angioplasty, Balloon, Coronary↗
PubMed2005

Consequences of different diagnostic "gold standards" in test accuracy research: Carpal Tunnel Syndrome as an example.

Test accuracy studies assume the existence of a well-defined illness definition and clear-cut diagnostic gold standards or reference standards. However, in clinical reality illness definitions may be vague or a mere description of a set of manifestations, mostly clinical signs and symptoms. This can lead to disagreements among experts about the correct classification of an illness and the adequate reference standard. Using data from a diagnostic accuracy study in carpal tunnel syndrome, we explored the impact of different definitions on the estimated test accuracy and found that estimated test performance characteristics varied considerably depending on the chosen reference standard. In situations without a clear-cut illness definition, randomized controlled trials may be preferable to test accuracy studies for the evaluation of a novel test. These studies do not determine the diagnostic accuracy, but the clinical impact of a novel test on patient management and outcome.

Carpal Tunnel Syndrome↗
PubMed2005

Meta-analysis: accuracy of rapid tests for malaria in travelers returning from endemic areas.

BACKGROUND: Microscopic diagnosis of malaria is unreliable outside specialized centers. Rapid tests have become available in recent years, but their accuracy has not been assessed systematically. PURPOSE: To determine the accuracy of rapid diagnostic tests for ruling out malaria in nonimmune travelers returning from malaria-endemic areas. DATA SOURCES: The authors searched MEDLINE, EMBASE, CAB Health, and CINAHL (1988 to September 2004); hand-searched conference proceedings; checked reference lists; and contacted experts and manufacturers. STUDY SELECTION: Diagnostic accuracy studies in nonimmune individuals with suspected malaria were included if they compared rapid tests with expert microscopic examination or polymerase chain reaction tests. DATA EXTRACTION: Data on study and patient characteristics and results were extracted in duplicate. The main outcome was the likelihood ratio for a negative test result (negative likelihood ratio) for Plasmodium falciparum malaria. Likelihood ratios were combined by using random-effects meta-analysis, stratified by the antigen targeted (histidine-rich protein-2 [HRP-2] or parasite lactate dehydrogenase [LDH]) and by test generation. Nomograms of post-test probabilities were constructed. DATA SYNTHESIS: The authors included 21 studies and 5747 individuals. For P. falciparum, HRP-2-based tests were more accurate than parasite LDH-based tests: Negative likelihood ratios were 0.08 and 0.13, respectively (P = 0.019 for difference). Three-band HRP-2 tests had similar negative likelihood ratios but higher positive likelihood ratios compared with 2-band tests (34.7 vs. 98.5; P = 0.003). For P. vivax, negative likelihood ratios tended to be closer to 1.0 for HRP-2-based tests than for parasite LDH-based tests (0.24 vs. 0.13; P = 0.22), but analyses were based on a few heterogeneous studies. Negative likelihood ratios for the diagnosis of P. malariae or P. ovale were close to 1.0 for both types of tests. In febrile travelers returning from sub-Saharan Africa, the typical probability of P. falciparum malaria is estimated at 1.1% (95% CI, 0.6% to 1.9%) after a negative 3-band HRP-2 test result and 97% (CI, 92% to 99%) after a positive test result. LIMITATIONS: Few studies evaluated 3-band HRP-2 tests. The evidence is also limited for species other than P. falciparum because of the few available studies and their more heterogeneous results. Further studies are needed to determine whether the use of rapid diagnostic tests improves outcomes in returning travelers with suspected malaria. CONCLUSIONS: Rapid malaria tests may be a useful diagnostic adjunct to microscopy in centers without major expertise in tropical medicine. Initial decisions on treatment initiation and choice of antimalarial drugs can be based on travel history and post-test probabilities after rapid testing. Expert microscopy is still required for species identification and confirmation.

Aldehyde-Lyases↗
PubMed2005

Diagnostic value of sonography in patients with suspected carpal tunnel syndrome: a prospective study.

OBJECTIVE: To determine the diagnostic value of sonography in patients with suspected carpal tunnel syndrome (CTS). METHODS: We conducted a prospective study of 110 wrists in 74 consecutive patients with suspected CTS who had been referred to a tertiary care center. We determined the largest cross-sectional area of the median nerve at the carpal tunnel. Because of the lack of a universally accepted reference standard, we first examined the association of sonography with nerve conduction. Then, we compared sonography with a reference standard based on the combination of nerve conduction studies and signs and symptoms. Sonography and reference standard tests were performed independently and interpreted under blinded conditions. Based on a fitted receiver operating characteristic curve, we estimated likelihood ratios (LRs) and posttest probabilities for different cutoffs. RESULTS: There was a high concordance between sonography and nerve conduction. Based on the combined reference standard, a cutoff of 10 mm(2) resulted in approximately equal sensitivity and specificity, but only moderate LRs. A cutoff of <8 mm(2) had satisfactory power to rule out CTS: the fitted-negative LR was 0.13. Conversely, a cutoff of > or =12 mm(2) had excellent power to rule in CTS, with a fitted-positive LR of 19.9. For nerves > or =12 mm(2) and a pretest probability of 70% expected in patients with suspected CTS in tertiary care, we found a posttest probability of CTS of 98%. CONCLUSION: Depending on setting and purpose, different cutoff values for the largest cross-sectional area may be used to accurately rule in or rule out CTS. Using sonography as a first-line test may cost-effectively reduce the number of nerve conduction studies in patients with suspected CTS. A large-scale, randomized controlled trial is required to determine the effects of sonography on clinical outcomes, the number of nerve conduction studies performed, and the total cost.

Adult↗
PubMed2005

Assessing bone loss on radiographs of the knee in osteoarthritis: a cross-sectional study.

OBJECTIVE: The only established system to grade subchondral bone attrition in knee osteoarthritis (OA) has low interobserver reliability. In this study, our aim was to convert this system into a reliable tool for the assessment of subchondral bone loss in knee OA. METHODS: Templates that were designed to outline the normal contours of the knee were overlaid onto conventional radiographs of a random sample of 100 knees of OA patients who were awaiting total knee replacement (TKR). Seventy-five films from individuals with chronic knee pain who were not awaiting TKR and 75 films from asymptomatic control subjects were also assessed. Bone loss was graded from 0 (no attrition) to 3 (severe attrition of >10 mm); other established radiologic features were also graded. Spearman's rho was used to determine the correlation of attrition scores with other features, and logistic regression was used to explore whether definite bone attrition was associated with night pain. RESULTS: The inter- and intraobserver reliability values were high for attrition scores and for the presence of definite attrition (score > or =2). Bone attrition was evident in 62% of films from patients awaiting TKR, in 9% of films from individuals with chronic knee pain who were not awaiting TKR, and in 1% of films from controls. In all groups, the correlation between attrition and other features was weak to moderate. There was a nonsignificant association between definite bone attrition and night pain. CONCLUSION: Bone attrition is an additional dimension of knee OA that can be measured reliably. Definite attrition may be associated with night pain.

Aged↗
PubMed2004

Effect of a flow chart on use of blood transfusions in primary total hip and knee replacement: prospective before and after study.

PROBLEM: A suspected high proportion of unnecessary blood transfusions occur in patients undergoing total joint replacement. DESIGN: Prospective before and after study evaluating the impact of a one page flow chart aimed at reducing the use of blood transfusions. SETTING: Orthopaedic tertiary care centre in Winterthur, Switzerland. 208 patients underwent primary total joint replacement of hips or knees during the control period (October 1998 to September 1999) and 217 during the intervention period (October 1999 to September 2000). KEY MEASURES FOR IMPROVEMENT: Proportion of patients receiving allogeneic blood transfusions. STRATEGIES FOR CHANGE: A simple one page flow chart, which summarised graphically the perioperative decision pathways for anaemic patients, was placed in all charts of patients undergoing total joint replacement and handed out to medical staff from 4 October 1999 onwards. The implementation of the flow chart focused on its endorsement by chief physicians and the development of a sense of "ownership" among physicians and nurses. EFFECTS OF CHANGE: The proportion of patients receiving allogeneic blood decreased from 35.0% to 19.8% (absolute difference -15.2%, 95% confidence interval -23.3 to -7.0%). The percentage of patients donating and receiving autologous blood also decreased. This led to overall savings of about 23,000 pounds sterling (42,470 dollars; 34,441 euros) (103.50 pounds sterlingper patient undergoing total joint replacement). Differences became more pronounced after adjustment for confounding factors. LESSONS LEARNT: Allogeneic blood transfusions in primary hip and knee replacement surgery may be reduced cost effectively by implementing a one page flow chart. Five key elements may have contributed: simplicity; wide distribution; no requirement for major changes; endorsement by local opinion leaders; and development of a sense of ownership. These elements may be used in other contexts to achieve sustained change of clinical practice.

Aged↗
PubMed2004

Low membrane protein sulfhydrils but not G6PD deficiency predict ribavirin-induced hemolysis in hepatitis C.

Hemolysis is a frequent adverse effect of ribavirin (RBV). It has been suggested that oxidative stress plays a role, but mechanisms and predictive risk factors for severe forms remain unknown. Markers of redox status were determined in erythrocytes of 34 patients with hepatitis C-four of them with glucose-6-phosphate-dehydrogenase (G6PD) deficiency-before and during treatment with RBV and interferon (IFN) and were compared with 10 healthy control subjects. In addition, erythrocytes were incubated with RBV, and the effects of dipyridamole (DPD), diethylmaleate (DEM), and glutathione ester (GSHE) were studied in vitro. Of the 30 patients without G6PD deficiency who were treated with RBV and IFN-alpha, five developed major hemolysis (Delta hemoglobin > 6 g/dL) and 25 developed minor hemolysis (Delta hemoglobin < 2.5 g/dL). Patients with major hemolysis had lower median pretreatment values of membrane protein sulfhydrils than patients with minor hemolysis (28.4 vs. 36.7 nmol/mg, P <.001). Erythrocytes of G6PD-deficient patients were not more susceptible to RBV-induced hemolysis. In in vitro incubations of erythrocytes, DEM enhanced the RBV-induced decrease of glutathione, protein sulfhydrils, and osmotic resistance. Supplementation of GSHE and DPD prevented the RBV-induced decrease in osmotic resistance, adenosyl triphosphate (ATP), and 2,3-diphosphoglycerate (DPG), the loss of glutathione and protein sulfhydrils, and the formation of thiobarbituric acid reactive substances (TBARs). In conclusion, the data indicate that low membrane protein sulfhydrils prior to therapy but not G6PD deficiency are predictive of RBV-induced major hemolysis. In vitro, GSHE and DPD reduce the RBV-associated oxidative stress in erythrocytes and prevent the increase in osmotic fragility, suggesting that these compounds might decrease the risk of hemolysis in patients.

Adult↗
PubMed2003

Systematic review of the epidemiologic and trial evidence of an association between antidepressant medication and breast cancer.

Biologic studies have suggested that antidepressant use may increase breast cancer risk. We conducted a systematic review of trials and controlled epidemiologic studies to assess this association. Pooled data from 31 primary efficacy drug company trials of fluoxetine suggested no increased risk but the short duration of these trials may have been insufficient to detect an association. In one prospective cohort study antidepressant use was associated with breast cancer, but this study was conducted among women attending for breast screening, and only limited data on antidepressant use were available. In a second large prospective drugs screening study no association was found between either amitriptyline or imipramine and breast cancer. In a large well-conducted retrospective cohort study there was no association between antidepressant use and breast cancer. A second retrospective cohort study was flawed, with exposure in those who developed breast cancer being measured over a shorter time period than in those who remained disease free. Two of four case-control studies found no association between antidepressant use and breast cancer after control for a number of potential confounding factors. We conclude that epidemiologic evidence does not support an association between antidepressant use and breast cancer.

Antidepressive Agents↗