[Hemorrhagic complications of oral anticoagulant therapy: results of a prospective multicenter study ISCOAT (Italian Study on Complications of Oral Anticoagulant Therapy)]. / Complicanze emorragiche della terapia anticoagulante orale: risultati dello studio prospettico multicentrico ISCOAT (Italian Study on Complications of Oral Anticoagulant Therapy).

BACKGROUND: To assess the incidence of bleeding complications during oral anticoagulant therapy (OAT) in a population of patients representative of daily practice in Italian anticoagulation clinics. DESIGN: prospective, inception-cohort, multicentre. SETTING: Thirty-four anticoagulation clinics federated in the Italian Federation of Anticoagulation Clinics. PATIENTS: 2745 consecutive patients, included from beginning of their first OAT course. Most patients were aged between 60 and 79 y (57.8%), with 8% being > or = 80 y. Venous thromboembolism was the most frequent indication for OAT (one third of all the patients), followed by non ischemic heart disease which mainly included atrial fibrillation (16.8% of patients). Warfarin (in 63.8% of patients) and acenocoumarol were the only anticoagulant drugs used. The targeted anticoagulation intensity was low (INR < or = 2.8) in 71% of patients and high (INR > 2.8) in the remainder. OUTCOMES: Fatal, major and minor bleeding events. Thrombotic events were also recorded, though not analyzed in the present report. FINDINGS: During the 2011 patient-years (pt-y) of follow-up, 153 bleeding complications (7.6% pt-y) were recorded--5 fatal (all cerebral haemorrhages, 0.25% pt-y), 23 major (1.1% pt-y) and 125 minor (6.2% pt-y). The rate of events did not vary according to sex, coumarin type, size of enrolling centre or targeted therapeutic range; it was higher in older patients (10.5% pt-y in those aged > or = 70 y, relative risk--RR--1.75, p < 0.001), in cases where indication for anti-coagulant treatment was peripheral and/or cerebrovascular disease (12.5% pt-y; RR 1.80, p < 0.01) and during the first 90 days of treatment (11% pt-y, RR 1.75, p < 0.001). One fifth of bleeding events occurred at a very low anticoagulation intensity (INR < 2; the category rate being 7.7% pt-y); the rate was 4.8% pt-y in the 2.0-2.9 INR category, reaching 9.5% pt-y, 40.5% pt-y and 200% pt-y in the 3-4.4, 4.5-6.9 and > or = 7 INR categories respectively (RR for INR levels > 4.5 = 7.91, p < 0.0001). CONCLUSIONS: The overall rate of bleeding events recorded in the present study was much lower than that recorded in other (including recent) observational and experimental studies. The risk of bleeding increased in the following cases: age > 70 y; arterial vascular disease as indication for OAT; first 3 months of treatment; INR values > or = 4.5. OAT has become safer in recent years, particularly if monitored in special anticoagulation clinics. Caution should be exercised when prescribing OAT in elderly patients and the intensity anticoagulation levels should be closely monitored to minimize incidental periods of overanticoagulation.

Thrombotic events during oral anticoagulant treatment: results of the inception-cohort, prospective, collaborative ISCOAT study: ISCOAT study group (Italian Study on Complications of Oral Anticoagulant Therapy).

The paper reports on rate and type of thrombotic events occurring during the observational, prospective, inception-cohort, multicenter ISCOAT study. 2,745 unselected, daily practice patients, consecutively referring to 34 Italian anticoagulation clinics to monitor the oral anticoagulant treatment, were included in the study from beginning of their first anticoagulant course. During a total follow-up of 2,011 patient-years of treatment 70 thrombotic events (3.5 per 100 patient years) were recorded in 67 patients: 20 fatal (1%), 39 major (1.9%) and 11 minor (0.6%). 34/70 events occurred within the first 90 days of treatment (relative risk - at multivariate analysis - of < or =90 days vs. >90 = 20.6, C.I. 12.7-33.5; p <0.0001). The risk was higher in patients aged > or =70 y (1.62, C.I. 1.0-2.61; p <0.05), and when indication for anticoagulant treatment was peripheral/cerebral arterial disease (1.84, C.I. 1.01-3.36; p <0.05). The frequency of thrombotic events was 17.5% when international normalised ratio (INR) levels were < 1.5, decreasing to 2.3% for INRs within the 2-2.99 category (relative risk of INRs <2.0 vs. > or =2 = 1.88, C.I. 1.16-3.07; p <0.05). The recorded rate of thrombotic events was lower than that reported in the few available studies. A greater risk should be expected during the first 90 days of treatment, when anticoagulation levels are <2.0 INR, in patients > 70 years and in those with cerebrovascular/peripheral arterial disease.

Bleeding complications of oral anticoagulant treatment: an inception-cohort, prospective collaborative study (ISCOAT). Italian Study on Complications of Oral Anticoagulant Therapy.

BACKGROUND: Bleeding is the most serious complication of the use of oral anticoagulation in the prevention and treatment of thromoboembolic complications. We studied the frequency of bleeding complications in outpatients treated routinely in anticoagulation clinics. METHODS: In a prospective cohort from thirty-four Italian anticoagulation clinics, 2745 consecutive patients were studied from the start of their oral anticoagulation (warfarin in 64%, acenocourmarol in the rest). The target anticoagulation-intensity was low (international normalised ratio [INR] < or = 2.8) in 71% of the patients and high (> 2.8) in the remainder. We recorded demographic details and the main indication for treatment and, every 3-4 months, INR and outcome events. Such events included all complications (bleeding, thrombosis, other), although only bleeding events are reported here, and deaths. We divided bleeding into major and minor categories. FINDINGS: 43% of the patients were women. Nearly three-fifths of the patients were aged 60-79; 8% were over 80. The main indication for treatment was venous thrombolism (33%), followed by non-ischaemic heart disease (17%). Mean follow-up was 267 days. Over 2011 patient-years of follow-up, 153 bleeding complications occurred (7.6 per 100 patient-years). 5 were fatal (all cerebral haemorrhages, 0.25 per 100 patient-years), 23 were major (1.1), and 125 were minor (6.2). The rate of events was similar between sexes, coumarin type, size of enrolling centre, and target INR. The rate was higher in older patients: 10.5 per 100 patient-years in those aged 70 or over, 6.0 in those aged under 70 (relative risk 1.75, 95% Cl 1.29-2.39, p < 0.001). The rate was also higher when the indication was peripheral and/or cerebrovascular disease than venous thromboembolism plus other indications (12.5 vs 6.0 per 100 patient-years) (1.80, 1.2-2.7, p < 0.01), and during the first 90 days of treatment compared with later (11.0 vs 6.3, 1.75, 1.27-2.44, p < 0.001). A fifth of the bleeding events occurred at low anticoagulation intensity (INR < 2, rate 7.7 per 100 patient-years of follow-up). The rates were 4.8, 9.5, 40.5, and 200 at INRs 2.0-2.9, 3-4.4, 4.5-6.9, and over 7, respectively (relative risks for INR > 4.5, 7.91, 5.44-11.5, p < 0.0001). INTERPRETATION: We saw fewer bleeding events than those recorded in other observational and experimental studies. Oral anticoagulation has become safer in recent years, especially if monitored in anticoagulation clinics. Caution is required in elderly patients and anticoagulation intensity should be closely monitored to reduce periods of overdosing.

Prophylaxis of venous thrombosis after gynaecological surgery: a controlled pilot study of defibrotide.

BACKGROUND: Defibrotide (Def), a new antithrombotic drug, has been proposed as a prophylactic agent in postoperative DVT. Most of the studies to date, however, have either not been controlled or have used unverifiable systems for asymptomatic DVT diagnosis. This randomized pilot study compared Def versus standard low-dose calcium heparin (CH) prophylaxis after gynaecological surgery, using objective criteria for DVT diagnosis. METHODS: Forty-one pts received 400 mg Def intramuscularly twice a day starting the day before surgery; 40 pts received 5000 IU CH s.c. twice daily beginning 2h before surgery. The two groups were well matched for all relevant risk factors. DVT was diagnosed by means of the 125I fibrinogen uptake test (FUT) and venography. Blood coagulation and fibrinolysis tests were also carried out perioperatively. RESULTS: Isotopic DVT (FUT-positive for two consecutive days) was recorded in 6 (14.6%) of the Def and 5 (12.5%) of the CH groups. In cases where FUT was positive for at least three consecutive days (4 in Def and 1 in CH), venography confirmed DVT in 3 cases (all in the Def group). No side-effects were recorded in either group and the amounts of transfused blood were not different. No significant differences in blood coagulation or fibrinolysis tests were recorded, except for higher fibrinogen levels on the 8th post-operative day in the Def group. CONCLUSIONS: These results do not indicate any trend suggesting that Def, as a prophylactic agent in gynaecological surgery, offers any clinical or practical advantages over standard low-dose heparin prophylaxis.