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Biomedical subjects

P Petersen

Publications and source records attributed to P Petersen.

At least 55 records · Page 3Linked to original sources
PubMed1997

Effect of fixed minidose warfarin, conventional dose warfarin and aspirin on INR and prothrombin fragment 1 + 2 in patients with atrial fibrillation.

The efficacy of conventional dose adjusted oral anticoagulation for stroke prevention in patients with non-valvular atrial fibrillation is well-documented but not considered ideal as primary antithrombotic treatment in elderly patients. The antithrombotic effect of fixed minidose warfarin 1.25 mg/day alone or in combination with aspirin 300 mg/day, of conventional dose adjusted warfarin (INR 2.0-3.0), and of aspirin 300 mg/day have been investigated in outpatients with chronic nonvalvular atrial fibrillation in the second Copenhagen Atrial Fibrillation, Aspirin and Anticoagulant Therapy Study (AFASAK 2). In order to investigate the effect on the coagulation system of the treatments, the International Normalized Ratio of the prothrombin time (INR) and prothrombin fragment 1 + 2 (F1 + 2) were monitored at baseline and after three months of treatment in 100 patients consecutively included in the trial. At baseline no differences in INR and F1 + 2 between the four treatment groups were present. After three months of therapy the level of INR increased significantly from baseline in patients receiving warfarin in any dose and the level of F1 + 2 decreased significantly by combined minidose warfarin-aspirin and by dose adjusted warfarin. When comparing the changes over time in F1 + 2 (three-month value minus baseline value) during therapy with fixed minidose warfarin, combined minidose warfarin-aspirin and aspirin alone no significant difference between the groups was found. In conclusion, INR was changed by all three warfarin regimens but only dose adjusted warfarin (INR 2.0-3.0) had a marked effect on F1 + 2.

Aged↗
PubMed1997

Prevention of thromboembolic events in atrial fibrillation.

Nonvalvular atrial fibrillation is associated with an overall risk of stroke of 4.5% per year. Advancing age, prior stroke or transcient cerebral ischemia, diabetes and hypertension are known risk factors. Ischemic stroke in patients with atrial fibrillation are generally more severe than ischemic stroke in patients with sinus rhythm. Warfarin is effective for primary and secondary prevention of ischemic stroke, reducing the risk by 68%. The effect of aspirin is still controversial, reducing the risk by 18-44%. Recent clinical trials have investigated the effect of warfarin given at a very low intensity either alone or combined with aspirin. The results from the SPAF III study demonstrated that a combination of mini-intensity warfarin plus aspirin was insufficient for stroke prevention in atrial fibrillation. Other trials now indicate, that oral anticoagulation at INR-values below 2.0 is not effective for stroke prevention in these patients. It is recommended that patients at high risk of stroke are treated with warfarin at an intensity of INR 2.0-3.0. Patients younger than 65 without other risk factors can be given aspirin 325 mg/day. The present clinical challenge is to ensure effective and safe oral anticoagulation to patients with atrial fibrillation at high risk of stroke.

Anticoagulants↗
PubMed1996

[Interaction between warfarin and nalidic acid].

A case of presumed interaction between warfarin and nalidixic acid is reported in an 84 year-old female in whom INR rose from 1.9 to 9.6 after start of treatment with nalidixic acid. The interaction may be caused by several factors: 1) Nalidixic acid may displace warfarin from plasma proteins and thereby increase the anticoagulant effect. 2) The fluoroquinolone drug enoxacin reduces the hepatic clearance of the R-stereomere of warfarin but without prolongation of the prothrombin time ratio. 3) Fluoroquinolones may affect the vitamin-K producing bacteria in the gut and thereby influence the vitamin-K: warfarin ratio in plasma. Only some patients develop hypoprothrombinaemia during concomitant therapy with warfarin and quinolone antimicrobials. It is hypothesized that the interaction may partly be related to age, sex or concomitant disease. Frequent control of INR in patients treated with both warfarin and quinolone antimicrobials is recommended.

Aged↗
PubMed1996

[Atrial fibrillation and apoplexy--risks and prevention].

The annual incidence of ischemic stroke among patients with chronic non-valvular atrial fibrillation is about 4.5 percent. In five controlled trials, oral anticoagulant therapy with warfarin reduced the annual incidence of stroke by 68 percent to 1.4 percent. The effect of aspirin has not been unequivocally determined. Aspirin reduced the annual risk of stroke by 18 percent (n.s.) in one trial, and by 44 percent in another, though the two trials differed both in mean age of the patients and in aspirin doses. Direct comparison of warfarin and aspirin revealed no difference in efficacy. Advanced age, previous stroke or transient ischemic attack (TIA), hypertension and diabetes were all found to be risk factors for stroke in patients with atrial fibrillation. In patients under 65 years of age without risk factors, the annual risk of stroke was 1 percent. After TIA or minor stroke, warfarin reduced the annual risk of a second stroke from 12 percent to 4 percent. Aspirin had no such effect. The annual incidence of major bleeding episodes was 0.2-2.0 percent in the warfarin-treated subgroup, 0.2-1.5 percent in the aspirin subgroup and 0-1.6 percent in the placebo subgroup. Based on findings in the above mentioned trials, warfarin (INR 2.0-3.0) is recommended for stroke prevention in patients over 60 years of age with non-valvular atrial fibrillation. Trials are under way to ascertain whether conventional warfarin treatment can be replaced by less complicated and safer treatments in patients with chronic atrial fibrillation.

Aged↗
PubMed1995

[Suicide and other causes of death in patients admitted for attempted suicide. 10-year follow-up].

The purpose of this study has been to describe the course over ten years and prognosis for a cohort of patients who had been admitted to a psychiatric department following a suicide attempt. The cohort consisted of 207 patients who had been admitted in the period 1.10.1980-20.4.1981 to a department of psychiatry following a suicide attempt. At the index attempt 99 patients were randomly selected and interviewed. Information on the remainder was obtained from psychiatric case histories, casualty records and discharge reports. Ten years after the index attempt information concerning death, date and cause was collected. Of the 207 patients involved, 52 (25.1%) were dead. Twenty-five (12.1%) had committed suicide, the remainder had died of natural, accidental or unknown causes. Relative to the general population the death rate from suicide and other causes was extremely high. Predictors of suicidal outcome were substance abuse and dangerous index attempt. At least one of these two predictors was present for 72% of those who committed suicide and for 43% of those who did not commit suicide. Aging and previous suicide attempts were the only significant predictors of other causes of death.

Adult↗
PubMed1995

[Cerebral comlications of surgery using cardiopulmonary bypass].

The number of open heart surgery procedures using cardiopulmonary bypass increases each year. The objective of this review is to describe the frequency of cerebral complications to such open heart surgery in 18 retrospective and prospective studies published after 1980. In prospective studies the overall frequency of central nervous system complications was 5-61% and the frequency of stroke and transitory ischaemic attack (TIA) was 2-24%. A total of 1-12% suffered from prolonged encephalopathy. In retrospective studies the frequency of central nervous complications was 1-2%. At neuropsychological tests 30-79% showed significant deterioration at the seventh to ninth postoperative day. After six months 80% achieved the same test results as prior to surgery. It is difficult to compare the studies because of major differences in study design. Stroke and TIA seemed to occur more frequent in older studies, in prospective studies and in studies based on valve surgery. Most studies were uncontrolled. We conclude that the risk of central nervous system complications to open heart surgery needs to be re-evaluated in prospective studies of well-defined patients, including matched control groups and a long follow-up period.

Cardiopulmonary Bypass↗
PubMed1995

Second Copenhagen Atrial Fibrillation, Aspirin, and Anticoagulant Therapy Study (AFASAK 2): Methods and Design.

Background: Seven randomized trials have demonstrated that anticoagulant therapy is effective for primary and secondary prevention of stroke and other thromboembolic events in patients with chronic nonvalvular atrial fibrillation. The effect of aspirin is still not clarified. Conventional anticoagulant therapy is inconvenient as a primary preventive therapy as it requires frequent blood tests and implies a risk of bleeding complications. Purpose and methods: The Second Copenhagen Atrial Fibrillation, Aspirin and Anticoagulant Therapy Study (The AFASAK 2 study) is a randomized, one center, primary prevention trial. Its purpose is to investigate the effect of four antithrombotic regimens in patients with atrial fibrillation (1) fixed dose warfarin 1.25 mg per day, (2) a combination of warfarin 1.25 mg per day and aspirin 300 mg per day, (3) aspirin 300 mg per day, and (4) conventional warfarin therapy (INR 2.0-3.0). The primary endpoint is a stroke or a thromboembolic event in viscera or extremities. Secondary endpoints are transient ischemic attack, myocardial infarction, or death. The study will evaluate outcome events on intention-to-treat principles. The rate of bleeding complications is evaluated. The aim is to obtain an antithrombotic therapy for patients with nonvalvular atrial fibrillation that is effective, safe, easy to administer, and inexpensive. The methods and design of the study are presented in this paper.

Journal Article↗
PubMed1995

[Bleeding complications in oral anticoagulant treatment].

Vitamin K-antagonists are recommended for the prevention of stroke in patients with chronic atrial fibrillation, recent myocardial infarction or prostatic heart valves. Anticoagulant therapy is seldom prescribed, however, presumably for fear of haemorrhagic sequelae. The risk of bleeding during anticoagulant therapy has been evaluated in 10 recent studies of warfarin treatment for the prevention of arterial thromboembolism. The mean annual incidences of fatal and major bleeding was 0.5 percent and 1.6 percent, respectively, as compared with the placebo figures of 0.1 percent and 0.6 percent, respectively. In 3 studies where the effect of aspirin has been evaluated the mean annual incidence of fatal and major bleeding was 0.2 percent and 0.8 percent, respectively. The figures for warfarin therapy where lower than those reported from older studies. The reasons for the reduction in incidence may be less intensive anticoagulant treatment than formerly, improved laboratory control by the introduction of the International Normalized Ratio, and careful pretreatment evaluation of patients selected for clinical trials.

Anticoagulants↗
PubMed1994

Laparoscopic deroofing of post-transplant lymphoceles.

Lymphocele is a most common surgical complication following renal transplantation. The indication for treatment is given when the lymphocele becomes symptomatic. We succeeded in laparoscopically deroofing large lymphoceles in nine patients that were causing ureter compression in eight and ipsilateral leg edema in six cases. The postoperative course was uneventful, and the surgery-related hospitalization did not exceed 7 days. Severe adhesions and a thick lymphocele wall, which made preparation difficult, resulted in the transection of the transplant ureter in one case. Techniques and prerequisites that would help to avoid this type of complication are discussed. According to CT scan or sonography, there was no recurrence in any of the patients after a mean follow-up of 11 months. This technique seems to be superior to other methods of treatment because not only is a cure obtained with a single intervention, but there is also a low risk of infection and a short hospitalization.

Adult↗
PubMed1994

Bleeding Complications to Long-Term Oral Anticoagulant Therapy.

Objective: To evaluate the incidence of bleeding complications in recent randomized trials on oral anticoagetlant treatment for prevention of arterial thromboembolism. Data sources: International publications on studies of prevention. of arterial thromboembolism by oral anticoagulant therapy. Study selection and data extraction: Randomized trials an oral anticoagulant therapy in patients with atrial fibrillation, recent myocardial infarction, and prosthetic heart valves were selected. For comparison older nonrandomized studies were studied. Background: Oral anticoagulant drugs are recommended for primary prevention of thromboembolic events in patients with chronic atrial fibrillation, recent myocardial infarction, and prosthetic heart valves. Still many physicians hesitate to prescribe anticoagulant drugs, presumably for fear of bleeding complications. Results: In six recent trials of warfarin in patients with atrial fibrillation, the highest annual incidence of fatal and major bleeding was 0.8% and 2.0%, respectively. In patients treated with warfarin after a recent myocardial infarction, the incidence of fatal and major bleeding was 0.2% and 0.5% per year, respectively. The annual incidence of fatal and major bleeding in patients with prosthetic heart valves on warfarin treatment was found to be 1.4% and 5.2%, respectively. The mean incidence of fatal and major bleeding in patients on warfarin in these eight trials was 0.5% and 1.7% per year, respectively. The mean incidence of fatal and major bleeds in patients on placebo was 0.1% and 0.7% per year, respectively. In three randomized trials evaluating aspirin versus warfarin, the respective mean incidences of fatal and major bleeding during aspirin treatment were 0.2% and 0.8% per year. A remarkable decrease in the incidence of major bleeding complications to oral anticoagulant therapy is revealed by these trials as compared to previous studies. Reasons for this decline may be less intensive anticoagulant regimes, better control of anticoagulant therapy due to the introduction of the international normalized ratio, and careful pretreatment evaluation of risk factors for bleeding. In alI prospective trials of oral anticoagulation, the risk of bleeding was more than over-weighed by the beneficial effect on the incidence of stroke and peripheral thromboemboli.

Journal Article↗
PubMed1994

Positive donor and negative recipient cytomegalovirus status is a detrimental factor for long-term renal allograft survival.

In 524 allogeneic cadaveric kidney transplants, the impact of cytomegalovirus (CMV) donor/recipient status on the incidence of CMV infection, CMV disease, early and long-term graft, and patient survival have been analyzed with respect to rejection episodes. Most CMV infections (59%) and diseases (17%) were found in CMV-negative recipients of CMV-positive kidneys. The 1-year function rate of CMV-positive kidneys (75%) dropped about 10% below that of CMV-negative organs (85%), and in the case of CMV-negative recipients an additional graft loss of more than 10% happened within the 4th and 5th years (5-year graft survival pos./neg.: 56%). This detrimental effect was exaggerated if it coincided with antibody-treated rejection episodes.

Adult↗
PubMed1994

Early infiltration of renal allografts with 27E10-positive macrophages and graft outcome.

Recently, we have demonstrated that acute cellular rejection is correlated with a massive infiltration of 27E10-positive macrophages. To examine the distribution of macrophage differentiation markers in the infiltrate in the very early post-transplantation period, two biopsies were taken intraoperatively, approximately 1 h following reperfusion, in each of 16 renal transplant recipients. One biopsy was taken for conventional histology and the other biopsy was snap-frozen. The sections were stained using an ABC indirect immunoperoxidase technique. A panel of monoclonal antibodies against three macrophage differentiation markers (27E10, 25F9 and RM3/1) was used to stain the sections. Using the early inflammation macrophage marker 27E10, there was an unexpected strong staining in 3 out of 16 biopsies. This severe infiltration of 27E10-positive macrophages with 10-20 macrophages per high power field (compared to 0-2 in others) was correlated in all cases with a poor outcome of the graft. All seven kidneys with no 27E10-positive infiltration showed a good function 6 weeks post-transplantation. The other macrophage markers, 25F9 and RM3/1, showed a less marked correlation with graft outcome. In conclusion, a massive infiltration of renal allografts with 27E10-positive macrophages 1 h post-transplantation may be a very early predictor of poor graft outcome.

Antigens, Surface↗
PubMed1993

McGill Pain Questionnaire translated into Danish: experimental and clinical findings.

OBJECTIVE: To develop a methodology for translating the McGill Pain Questionnaire (MPQ) into a Danish version, and to make comparisons to studies of patients speaking other languages. DESIGN: Finding suitable Danish adjectives using the same methodology as that in the original MPQ. Comparison of Danish descriptors to the words in the English version of MPQ. Survey in healthy subjects and patients with rheumatoid arthritis (RA) and fibromyalgia (F). SETTING: The general public and hospital outpatients. PATIENTS: A random sample of 186 healthy volunteers, 20 patients with rheumatoid arthritis and 41 patients with fibromyalgia. MAIN OUTCOME MEASURES: Danish words translated as closely as possible to the descriptors in the original McGill Pain Questionnaire. A pain-assessment instrument making international pain description possible. RESULTS: A Danish version of the McGill Pain Questionnaire was developed with scale values of Danish descriptors not differing more than 5 x SEM from the 'patient' words in the English version. The subdivision into classes and subclasses was respected. In the reliability experiment, the same rank values were found in 85% of subclasses. In a study using two experimental pain stimulus intensities, seven of 10 subjects obtained higher MPQ scores following the high-intensity stimulus. In the clinical study, the pain profiles of patients with RA and F in English, Italian, and Danish patients were almost the same. CONCLUSION: The present methodology of translating the McGill Pain Questionnaire permits comparison of studies from English-speaking and non-English-speaking populations, thus facilitating international research exchange.

Adult↗