The aim of this study has been twofold: 1 - to examine the impact of oral anticoagulant (OAC) use on a possible recent rise in the admission rate of intracerebral haemorrhages to Aberdeen Royal Infirmary (ARI), and 2 - to estimate the absolute risk of intracranial haemorrhage for outpatients followed up in the OAC Clinic at AR1. The number of patients admitted to ARI with intracerebral bleedings increased by 60% between 1993 and 1998. A corresponding increase in the proportion of patients with concurrent OAC use (4.7% vs 15.7%, p=0.055) cannot sufficiently explain the increase in the total number of intracerebral haemorrhages. The average annual incidence of intracranial haemorrhages for the OAC Clinic at ARI is found to be acceptably low at 0.33% per year. Further audit of the large number of patients receiving warfarin outwith the supervision of the clinic is urgently required.
HullR, DelmoreT, CarterCAdjusted subcutaneous heparin versus warfarin sodium in the longterm treatment of venous thrombosis. N Engl J Med1982; 306: 189–94.
4.
HullR, HirshJ, JayRDifferent intensities of oral anticoagulant therapy in the treatment of proximal-vein thrombosis. N Engl J Med1982; 307: 1676–81.
5.
TurpieAGG, GunstensenJ, HirshJ, NelsonH, GentM.Randomised comparison of Mo intensities of oral anticoagulant therapy after tissue heart valve replacement. Lancet1988; 1: 1242–45.
6.
SwurJN, SieckJO, MamoLAR, GallusAS. Trial of different intensities of anticoagulation in patents with prosthetic heart valves. N Engl J Med1990; 322: 428–32.
7.
TurpieAGG, GentM, LaupacisAA comparison of aspirin with placebo in patients treated with warfarin after heart-valve replacement. N Engl J Med1993; 329: 524–29.
8.
CannegieterSC, RosendaalFR, WintzenAR, van der MeerFJMVandenbrouckeJP, BriëtE.Optimal oral anticoagulant therapy in patients with mechanical heart valves. N Engl J Med1995; 333: 11–17.
9.
Sixty Plus Reinfarction Study Research Group. Risks of long-term oral anticoagulant therapy in elderly patients after myocardial infarction. Lancet1982; 1: 64–68.
10.
Enquěte de Prévention Secondaire de l'Infarctus du Myocarde (EPSIM) Research Group. A controlled comparison of aspirin and oral anticoagulants in prevention of death after myocardial infarction. N Engl J Med1982; 307: 701–8.
11.
SmithRAmesenH, HolmeI.The effect of warfarin on mortality and reinfarction after myocardial infarction. N Engl J Med1990; 323: 147–52
12.
Anticoagulants in the Secondary Prevention of Events in Coronary Thrombosis (ASPECT) Research Group. Effect of long-term oral anticoagulant treatment on mortality and cardiovascular morbidity after myocardial infaration. Lancet1994; 343: 499–503.
13.
PetersenP, BoysenG, GodtfredsenJ, AndersenED, AndersenB.Placebo-controlled, randomised trial of warfarin and aspirin for prevention of thromboembolic complications in chronic atrial fibrillation: the Copenhagen AFASAK Study. Lancet1989; 1: 175–79.
14.
Stroke Prevention in Atrial Fibrillation (SPAF) Study Group Investigators. Preliminary report of the Stroke Prevention in Atrial Fibrillation Study. N Engl J Med1990; 322: 863–68.
15.
The Boston Area Anticoagulation Trial for Atrial Fibrillation (BAATAF) Investigators. The effect of low dose warfarin on the risk of stroke in patients with nonrheumatic atrial fibrillation. N Engl J Med1900; 323: 1505–11.
EzekowitzMID, BridgersSIL, JamesKEWarfarin in the prevention of stroke associated with nonrheumatic atrial fibrillation. N Engl J Med1992; 327: 1406–12.
18.
European Atrial Fibrillation Trial (EAFT) Study Group. Secondary prevention in non-rheumatic atrial fibrillation after transient ischaemic attack or minor stroke. Lancet1993; 342: 1255–62.
19.
Stroke Prevention in Atrial Fibrillation (SPAF) Investigators. Warfarin versus aspirin for prevention of thromboembdism in atrial fibrillation: Stroke Prevention in Atrial Fibrillation II Study. Lancet1994; 343: 687–91.
20.
LevineM, HirshJ.Hemorrhagic complications of long-term anticoagulant therapy for ischemic cerebral vascular disease. Stroke1986; 17: 111–16.
21.
LandefeldCS, GoldmanL.Major bleeding in outpatients, treated with warfarin: incidence and prediction by factors known at the start of outpatient therapy. Am J Med1989; 87: 144–52.
22.
LaunbjergJ, EgebladH, HeafJ, NielsenNH, FugleholmAM, LadefogedK.Bleeding complications to oral anticoagulant therapy: multivariate analysis of 1010 treatment years in 551 outpatients. J Intern Med1991; 229: 351–5.
23.
FihnSID, McDonellM, MartinDRisk factors for complications of chronic anticoagulation. Ann Intern Med1993; 118: 511–20.
24.
van der MeerFJM, RosendaalFR, VandenbrouckeJP, BriëtE.Bleeding complications in oral anticoagulant therapy: an analysis of risk factors. Arch Intern Med1993, 153: 1557–62.
25.
PalaretiG, LealiN, CoccheriSBleeding complications of oral anticoagulant treatment: an inception-cohort prospective collaborative study (ISCOAT). Lancet1996; 348: 423–28.
26.
PettyGW, LennihanL, MohrJPComplications of long-term anticoagulation. Ann Neurol1988; 23: 570–74.
27.
ArmstrongPW, MantW.Bleeding risks, risk factors and management of bleeding complications after treatment with anticoagulants, specific antithrombins, thrombolytics, IIb-IIIa receptor blockers. Eur Heart J1995; 16 (Suppl L): 75–80.
28.
RådbergJA, OlssonJE, RådbergCT. Prognostic parameters in spontaneous intracerebral hematomas with special reference to anticoagulant treatment. Stroke1991; 22: 571–76.
29.
BroderickJP, PhillipsSJ, WhisnantJP, O'FallonWM, BergstrahlEJIncidence rates of strokes in the eighties: the end of the decline in stroke?Stroke1989; 20: 577–82.
30.
KotilaM.Declining incidence and mortality of stroke?Stroke1984; 15: 255–59.
31.
TeréntA.Increasing incidence of stroke among Swedish women. Stroke1988; 19: 598–603.
32.
MayoNE, GoldbergMS, LevyAR, DanysI, Korner-BitenskyN.Changing rates of stroke in the province of Quebec, Canada: 1981–1988. Stroke1991; 22: 590–95.
33.
ChyatteD, NolteKB, ChenTL, ViscoliCM, BrassLM. Changes in the incidence and mortality of intracerebral hemorrhage. Stroke1992; 23: 135.
34.
HartRG, BoopBS, AndersonDC. Oral anticoagulants and intracranial hemorrhage: facts and hypotheses. Stroke1995; 26: 1471–77.
35.
DiamondT, GrayWJ, CheeCP, FanninTF. Subdural haematoma associated with long term oral anticoagulation. Br J Neurosurg1988; 2: 351–56.
36.
MathiesenT, BenediktsdottirK, JohnssonH, LindqvistM, van HolstH.Intracranial traumatic and non-traumatic haemorrhagic complications of warfarin treatment. Acta Neurol Scand1995; 91: 208–14.
37.
RoweCC, DonnanGA, BladinPF. Intracerebral haemorrhage: incidence and use of computed tomography. Br Med J1988; 297: 1177–78.
WintzenAR, de JongeH, LoeligerEA, BotsGTAM. The risk of intracerebral hemorrhage during oral anticoagulant treatment: a population study. Ann Neurol1984; 16: 553–58.
LacroixP, PortefaixO, BouchierMConditions de survenue des accidents hémorragiques intracrěniens des antivitamines KArch Mal Coeur1994; 87: 1715–19.
50.
VolansAP. The risks of minor head injury in the warfarinised patient. J Accid Emerg Med1998; 15: 159–61.
51.
GustafssonC, AsplundK, BrittonM, NorrvingB, OlssonB, MarkeL-A. Cost effectiveness of primary stroke prevention in atrial fibrillation: Swedish national perspective. Br Med J1992, 305: 1457–60.
