D Bates

University of Newcastle, Newcastle, New South Wales, Australia

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Publications (65)242.12 Total impact

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    ABSTRACT: Background The management of unruptured intracranial aneurysms requires knowledge of the natural history of these lesions and the risks of repairing them. Methods A total of 2621 patients at 53 participating centers in the United States, Canada, and Europe were enrolled in the study, which had retrospective and prospective components. In the retrospective component, we assessed the natural history of unruptured intracranial aneurysms in 1449 patients with 1937 such aneurysms; 727 of the patients had no history of subarachnoid hemorrhage from a different aneurysm (group 1), and 722 had a history of subarachnoid hemorrhage from a different aneurysm that had been repaired successfully (group 2). In the prospective component, we assessed treatment-related morbidity and mortality in 1172 patients with newly diagnosed unruptured intracranial aneurysms. Results In group 1, the cumulative rate of rupture of aneurysms that were less than 10 mm in diameter at diagnosis was less than 0.05 percent per year, and in group 2, the rate was approximately 11 times as high (0.5 percent per year). The rupture rate of aneurysms that were 10 mm or more in diameter was less than 1 percent per year in both groups, but in group 1, the rate was 6 percent the first year for giant aneurysms (greater than or equal to 25 mm in diameter). The size and location of the aneurysm were independent predictors of rupture. The overall rate of surgery-related morbidity and mortality was 17.5 percent in group 1 and 13.6 percent in group 2 at 30 days and was 15.7 percent and 13.1 percent, respectively, at 1 year. Age independently predicted surgical outcome. Conclusions The likelihood of rupture of unruptured intracranial aneurysms that were less than 10 mm in diameter was exceedingly low among patients in group 1 and was substantially higher among those in group 2. The risk of morbidity and mortality related to surgery greatly exceeded the 7.5-year risk of rupture among patients in group 1 with unruptured intracranial aneurysms smaller than 10 mm in diameter. (N Engl J Med 1998;339:1725-33.) (C) 1998, Massachusetts Medical Society.
    New England Journal of Medicine 12/1998; 339(24):1725-1733. · 55.87 Impact Factor
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    ABSTRACT: The original Whickham Survey documented the prevalence of diabetes and lipid disorders in a sample of 2779 adults aged 18 years and over, which matched the British population structure. The aim of the 20-year follow-up study was to determine the incidence and natural history of diabetes. Outcomes in terms of morbidity and mortality at follow-up were determined in over 97% of the original population. Ninety-four subjects had been identified and treated for diabetes since the first survey, including 17 subjects identified as having a fasting plasma glucose > or = 7.8 mmol l-1 at follow-up. The incidence of diabetes for the total population was 2.2 1000-1 year-1 (95% confidence interval 1.8, 2.6). The risk factors identified at first survey were corrected for age, cut-off at the 95 centile and entered into a log linear model. Those which strongly predicted development of diabetes in the total population were fasting blood glucose (odds ratio (OR) (with 95% confidence intervals) = 2.3 (1.5, 3.5)) and body mass index (OR = 2.2 (1.5, 3.3)) in men, and fasting blood glucose (OR = 2.6 (1.7, 4.1)) and fasting serum triglyceride (OR = 2.8 (1.8, 4.4)) in women. A logit model has enabled the calculation of the probability of developing diabetes 20 years later. It was the characteristics of becoming older such as obesity, hypertriglyceridaemia, and raised fasting blood glucose, rather than age itself, which were associated with the development of diabetes.
    Diabetic Medicine 08/1996; 13(8):741-7. DOI:10.1002/(SICI)1096-9136(199608)13:8<741::AID-DIA173>3.0.CO;2-4 · 3.12 Impact Factor
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    ABSTRACT: The original Whickham Survey documented risk factors for cardiovascular disease and the prevalence of thyroid disorders in a sample of 2779 adults that closely matched the British population. A 20-year follow-up study has determined outcomes in terms of morbidity and mortality from ischemic heart disease in over 97% of the original survey population. Analysis of deaths from all causes and from ischemic heart disease showed no association with antithyroid antibody status identified at first survey. A multiple logistic regression using the development of ischemic heart disease in the total population at follow-up as the dependent variable found that the significant predictor variables for men were age, cholesterol, mean arterial blood pressure, smoking history, and skinfold thickness index. For women only age, cholesterol, and mean arterial blood pressure were significant. The presence of autoimmune thyroid disease, as defined by either hypothyroidism, positive antithyroid antibodies, or raised serum thyrotropin at first survey, was not significant. A retrospective cohort study of a subsample of women identified at first survey with positive antithyroid antibodies or raised serum thyrotropin and closely matched controls found no significant association with mortality or development of ischemic heart disease. There is no evidence from this study to suggest that evidence of autoimmune thyroid disease identified 20 years ago is associated with an increased risk of ischemic heart disease.
    Thyroid 07/1996; 6(3):155-60. · 4.49 Impact Factor
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    ABSTRACT: Background and Purpose: Little is known about different varieties of transient monocular blindness (TMB) in relation to the subsequent occurrence of vascular outcome events. Very few studies have addressed the prognostic value of the form of the attack in patients with TMB. To try and distinguish benign and hazardous symptoms of TMB, we studied the prognosis of different subtypes of TMB in terms of subsequent vascular complications. Methods: We analysed the characteristics of transient monocular loss of vision, vascular risk factors, and vascular events during follow-up in patients with TMB, who were recorded in the Royal Victoria Infirmary, Newcastle, United Kingdom (n = 137) or were entered into the Dutch TIA Trial (n = 185). The mean follow-up period was 5.0 years. The attacks were categorized in different 'patterns'. These patterns were related to the occurrence of (1) the combined event of vascular death, stroke or myocardial infarction and (2) cerebral infarction (fatal or non-fatal). Results: Patients with attacks of blurred vision had a more than twofold risk of vascular outcome events than patients with blackened vision, complete or in part [hazard ratio (HR) 2.3; 95% confidence limits (CL) 1.2–4.5]. Involvement of only a part of the visual field of one eye during the attack (instead of complete loss of vision) carried a lower risk (HR 0.4; 95% CL 0.2–0.9). Conclusion: Our findings suggest a relation between different types of TMB and outcome, but this needs to be validated in a subsequent cohort.
    Cerebrovascular Diseases 06/1996; 6(4):241-247. DOI:10.1159/000108028 · 3.75 Impact Factor
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    ABSTRACT: The original Whickham Survey documented the prevalence of thyroid disorders in a randomly selected sample of 2779 adults which matched the population of Great Britain in age, sex and social class. The aim of the twenty-year follow-up survey was to determine the incidence and natural history of thyroid disease in this cohort. Subjects were traced at follow-up via the Electoral Register, General Practice registers, Gateshead Family Health Services Authority register and Office of Population Censuses and Surveys. Eight hundred and twenty-five subjects (30% of the sample) had died and, in addition to death certificates, two-thirds had information from either hospital/General Practitioner notes or post-mortem reports to document morbidity prior to death. Of the 1877 known survivors, 96% participated in the follow-up study and 91% were tested for clinical, biochemical and immunological evidence of thyroid dysfunction. Outcomes in terms of morbidity and mortality were determined for over 97% of the original sample. The mean incidence (with 95% confidence intervals) of spontaneous hypothyroidism in women was 3.5/1000 survivors/year (2.8-4.5) rising to 4.1/1000 survivors/year (3.3-5.0) for all causes of hypothyroidism and in men was 0.6/1000 survivors/year (0.3-1.2). The mean incidence of hyperthyroidism in women was 0.8/1000 survivors/year (0.5-1.4) and was negligible in men. Similar incidence rates were calculated for the deceased subjects. An estimate of the probability of the development of hypothyroidism and hyperthyroidism at a particular time, i.e. the hazard rate, showed an increase with age in hypothyroidism but no age relation in hyperthyroidism. The frequency of goitre decreased with age with 10% of women and 2% of men having a goitre at follow-up, as compared to 23% and 5% in the same subjects respectively at the first survey. The presence of a goitre at either survey was not associated with any clinical or biochemical evidence of thyroid dysfunction. In women, an association was found between the development of a goitre and thyroid-antibody status at follow-up, but not initially. The risk of having developed hypothyroidism at follow-up was examined with respect to risk factors identified at first survey. The odds ratios (with 95% confidence intervals) of developing hypothyroidism with (a) raised serum TSH alone were 8 (3-20) for women and 44 (19-104) for men; (b) positive anti-thyroid antibodies alone were 8 (5-15) for women and 25 (10-63) for men; (c) both raised serum TSH and positive anti-thyroid antibodies were 38 (22-65) for women and 173 (81-370) for men. A logit model indicated that increasing values of serum TSH above 2mU/l at first survey increased the probability of developing hypothyroidism which was further increased in the presence of anti-thyroid antibodies. Neither a positive family history of any form of thyroid disease nor parity of women at first survey was associated with increased risk of developing hypothyroidism. Fasting cholesterol and triglyceride levels at first survey when corrected for age showed no association with the development of hypothyroidism in women. This historical cohort study has provided incidence data for thyroid disease over a twenty-year period for a representative cross-sectional sample of the population, and has allowed the determination of the importance of prognostic risk factors for thyroid disease identified twenty years earlier.
    Clinical Endocrinology 08/1995; 43(1):55-68. DOI:10.1111/j.1365-2265.1995.tb01894.x · 3.46 Impact Factor
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    ABSTRACT: Background. A number of studies have demonstrated the efficacy of oral anticoagulant therapy in reducing the risk of stroke and systemic embolism in patients with nonrheumatic atrial fibrillation, However, both the targeted and the actual levels of anticoagulation differed widely among the studies, and a number of studies failed to report standardized prothrombin-time ratios as international normalized ratios (INRs), We therefore performed an analysis to determine the intensity of oral anticoagulant therapy in nonrheumatic atrial fibrillation that provides the best balance between the prevention of thromboembolism and the occurrence of bleeding complications. Methods. We calculated INR-specific incidence rates for both ischemic and major hemorrhagic events occurring in 214 patients who received anticoagulant therapy in the European Atrial Fibrillation Trial, a secondary-prevention trial in patients with nonrheumatic atrial fibrillation and a recent episode of minor cerebral ischemia. Results. The optimal intensity of anticoagulation was found to lie between an INR of 2.0 and an INR of 3.9. No treatment effect was apparent with anticoagulation below an INR of 2.0, The rate of thromboembolic events was lowest at INRs from 2.0 to 3.9, and most major bleeding complications occurred with treatment at intensities with INRs of 5.0 or above. Conclusions. To achieve optimal levels of anticoagulation with the lowest risk in patients with atrial fibrillation and a recent episode of cerebral ischemia, the target value for the INR should be set at 3.0, and values below 2.0 and above 5.0 should be avoided.
    New England Journal of Medicine 07/1995; 333(1):5-10. · 55.87 Impact Factor
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    ABSTRACT: This report describes a patient who had clinical features of both motor neuron disease and Parkinson's disease. Neuropathological examination and immunocytochemical studies showed that he had motor neuron disease of the progressive muscular atrophy type, and Lewy body Parkinson's disease, with intracytoplasmic inclusion bodies characteristic of both conditions. This is the first detailed description of these two diseases occurring concurrently in the same patient. A review of all previously reported cases of combined motor neuron disease and parkinsonism has led to the following conclusions: (1) that these two neuropathologically defined diseases occur together very infrequently, but (2) that parkinsonism and substantia nigra degeneration are not uncommon as part of the multi-system disease process underlying motor neuron disease.
    Acta Neuropathologica 02/1995; 89(3):275-283. DOI:10.1007/BF00309344 · 10.76 Impact Factor
  • H. Rodgers · P. Aitken · J. Murdy · D. Bates · O.F.W. James ·

    Age and Ageing 01/1995; 24(suppl 1):P5-P5. DOI:10.1093/ageing/24.suppl_1.P5-c · 3.64 Impact Factor
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    ABSTRACT: A 12 month longitudinal study has been performed on 118 subjects following first-ever stroke to determine changes in central motor conduction time (CMCT) to upper limb muscles. The responses to electromagnetic stimulation of the motor cortex and cervical motor roots were recorded bilaterally in the surface electromyograms of pectoralis major, biceps and triceps brachii and thenar muscles. The CMCTs obtained from these recordings in stroke patients have been compared with those obtained in 53 normal healthy subjects of a similar age. The first measurements were made within the immediate post-stroke period (12-72 h of the onset of symptoms) and repeated at set time intervals over 12 months. The first assessment of CMCT identified three groups: those with normal responses, delayed responses and absent responses. During the first 12 months following stroke various changes in CMCT occurred. Central motor conduction time may remain unchanged, delayed CMCT may return to normal and previously absent responses may reappear and be delayed or normal. Using electromagnetic stimulation of the motor cortex the thresholds for motor evoked responses in the different muscles were initially high and fell over 12 months.
    Brain 01/1994; 116 ( Pt 6)(6):1355-70. DOI:10.1093/brain/116.6.1355 · 9.20 Impact Factor
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    ABSTRACT: A longitudinal study was performed on 118 first-ever stroke patients to evaluate neurophysiological measurements of central motor conduction time (CMCT) in the period immediately following stroke as predictors of functional outcome and mortality at 12 months. Measurements of CMCT were made as described in the accompanying article (Heald et al., 1993, Brain, 116, 1355-1370), in which the following three groups of patients were recognized within 12-72 h after the onset of symptoms: normal response group, delayed response group and no response group. Neurophysiological and clinical investigations were commenced 12-72 h (designated as day 1) after the onset of symptoms and repeated at set time intervals up to 12 months. The subjects were examined neurologically and assessed using the Motricity Index for muscle strength, the Nine-hole Peg Test to measure manual dexterity, the Barthel Score for activities of daily living and the modified Rankin Scale for functional outcome. The duration of stay in hospital and the occurrence of stroke-related death were noted. During the first week following stroke, absence of responses correlated closely with the patient's symptoms and neurological observations of abnormal muscle tone and tendon reflexes. Correlations were made in the three groups of patients of functional scores at day 1 and at 12 months. Patients with normal CMCT had consistently higher scores throughout the 12 month period and achieved significantly better functional recovery. Patients with no responses showed poor performance in neurological and functional tests throughout the 12 month period. Patients with delayed CMCT had neurological and functional scores intermediate between those of the other two groups, but outcome at 12 months was similar to those in the normal response group. Where the threshold to cortical stimulation was abnormally high, functional outcome was generally poor. Mortality was highest in the group with absent responses and the survivors spent the longest period in hospital. In conclusion, the observation of normal or delayed CMCT at day 1 identifies a group of patients with a high probability of survival and functional recovery. The absence of responses to cortical stimulation at day 1 identifies a group of patients who are at high risk of poor functional recovery at 12 months and greater probability of stroke-related death during this period.
    Brain 01/1994; 116 ( Pt 6)(6):1371-85. DOI:10.1093/brain/116.6.1371 · 9.20 Impact Factor
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    ABSTRACT: Several studies have established the value of anticoagulation for primary prevention of thromboembolic events in patients with non-rheumatic atrial fibrillation (NRAF). However, in patients with a recent transient ischaemic attack (TIA) or minor ischaemic stroke the preventive benefit of anticoagulation or aspirin remains unclear. Physicians in 108 centres from 13 countries collaborated to study this question. 1007 NRAF patients with a recent TIA or minor ischaemic stroke were randomised to open anticoagulation or double-blind treatment with either 300 mg aspirin per day or placebo (group 1, 669). Patients with contraindications to anticoagulation were randomised to receive aspirin or placebo (group 2, 338). The measure of outcome was death from vascular disease, any stroke, myocardial infarction, or systemic embolism. During mean follow-up of 2.3 years, the annual rate of outcome events was 8% in patients assigned to anticoagulants vs 17% in placebo-treated patients in group 1 (hazard ratio [HR] 0.53; 95% confidence interval [CI] 0.36-0.79). The risk of stroke alone was reduced from 12% to 4% per year (HR 0.34; 95% CI 0.20-0.57). Among all patients assigned to aspirin (groups 1 and 2), the annual incidence of outcome events was 15%, against 19% in those on placebo (HR 0.83; 95% CI 0.65-1.05). Anticoagulation was significantly more effective than aspirin (HR 0.60; 95% CI 0.41-0.87). The incidence of major bleeding events was low, both on anticoagulation (2.8% per year) and on aspirin (0.9% per year). No intracranial bleeds were identified in patients assigned to anticoagulation. We conclude that anticoagulation is effective in reducing the risk of recurrent vascular events in NRAF patients with a recent TIA or minor ischaemic stroke. In absolute terms: 90 vascular events (mainly strokes) are prevented if 1000 patients are treated with anticoagulation for one year. Aspirin is a safe, though less effective, alternative when anticoagulation is contraindicated; it prevents 40 vascular events each year for every 1000 treated patients.
    The Lancet 11/1993; 342(8882):1255-1262. DOI:10.1016/0140-6736(93)92358-Z · 45.22 Impact Factor
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    ABSTRACT: Previous studies have reported a U-shaped relation between alcohol consumption and stroke. Those studies have been criticized for failing to distinguish between lifelong abstainers from alcohol and those who have given up drinking. We examined current and previous drinking habits of 364 cases of acute stroke and 364 community-based control subjects matched for age, sex, and family practitioner. Stroke patients were more likely to have been lifelong abstainers from alcohol than were the control subjects. The odds ratio (OR) or lifelong abstainers versus those who had ever drunk regularly was 2.36 (95% confidence interval [CI], 1.67 to 3.37). No relation was found between stroke and current nondrinkers. Current male heavy drinkers also had an increased risk of stroke (OR, 2.88; 95% CI, 1.08 to 2.31). Lifelong abstention from alcohol is associated with an increased risk of stroke. Moderate alcohol consumption may protect against cerebrovascular disease.
    Stroke 11/1993; 24(10):1473-7. DOI:10.1093/ageing/22.suppl_2.P3-c · 5.72 Impact Factor

  • Age and Ageing 01/1993; 22(suppl 2):P3-P4. DOI:10.1093/ageing/22.suppl_2.P3-d · 3.64 Impact Factor

  • Age and Ageing 01/1993; 22(suppl 2):P4-P4. DOI:10.1093/ageing/22.suppl_2.P4-c · 3.64 Impact Factor
  • P J Shaw · P G Ince · J Goodship · J Burn · J Slade · D Bates · D G Medwin ·
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    ABSTRACT: We describe a family in which infantile Werdnig-Hoffmann disease and adult-onset progressive muscular atrophy both occurred. The possibility of these two diseases developing within the same family by chance is unlikely, and several genetic hypotheses may be put forward to explain the association. We suggest that the molecular pathogenesis of these two subtypes of lower motor neuron degeneration may be linked. The genetic defect in the childhood spinal muscular atrophies has been mapped to chromosome 5q in close proximity to the microtubule-associated protein 1B locus. The association of diseases within this family suggests that chromosome 5q should also be studied in relation to adult-onset familial motor neuron disease.
    Neurology 09/1992; 42(8):1477-80. DOI:10.1212/WNL.42.8.1477 · 8.29 Impact Factor
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    D A Spriggs · D J Burn · J French · N E Cartlidge · D Bates ·
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    ABSTRACT: A randomized study of 110 patients undergoing their first diagnostic lumbar puncture was performed to compare the effect of immediate mobilization with 4 hours bed rest on the incidence of post lumbar puncture headache. There was no difference between the mobile (n = 54) and bed rest (n = 56) groups in the incidence of post lumbar puncture headache (32% versus 31%, respectively). We conclude that bed rest following lumbar puncture may be an unnecessary imposition on the patient, as well as on nursing staff.
    Postgraduate Medical Journal 08/1992; 68(801):581-3. DOI:10.1136/pgmj.68.801.581 · 1.45 Impact Factor
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    ABSTRACT: In a case-controlled study we recruited 400 patients admitted to hospital with stroke and 400 community controls matched for age, gender and family practitioner. Snoring history was obtained from 326 patients and 345 controls. Odds ratio for admission to hospital with stroke was 3.2 (95 per cent confidence intervals 2.3-4.4) for regular snorers against those who did not snore regularly. This risk was independent for age, gender and other risk factors for stroke. Snoring did not increase the chances of stroke during sleep. Level of consciousness was reduced more frequently in snorers (p = 0.0003). As the frequency of snoring increased so did the mortality to 6 months (p = 0.0006). Snoring is an important risk factor for stroke and adversely affects the prognosis in patients admitted to hospital with stroke.
    The Quarterly journal of medicine 08/1992; 83(303):555-62.
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    A M Glenn · P J Shaw · J W Howe · D Bates ·
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    ABSTRACT: Retinal migraine is not uncommon, but permanent sequelae in the anterior visual pathway are rare. We describe the case of a young woman in whom blindness developed over a six-year period due to recurrent episodes of migraine-related occlusions of a branch retinal artery.
    British Journal of Ophthalmology 04/1992; 76(3):189-90. DOI:10.1136/bjo.76.3.189 · 2.98 Impact Factor
  • D A Spriggs · J M French · J M Murdy · O F James · D Bates ·
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    ABSTRACT: In a case-controlled study into the risk factors for admission to hospital with stroke, 400 subjects and 400 age and sex-matched controls were recruited. All bar two subjects were followed until death or 6 months. Previous stroke and regular snoring (p = 0.0013 and p less than 0.0001 respectively) were the only two risk factors adversely to effect mortality. Transient ischaemic attack, ischaemic heart disease, hypertension, atrial fibrillation, diabetes mellitus did not significantly effect prognosis. An apparent beneficial effect of drinking alcohol and smoking became insignificant when the confounding influence of age was taken into account.
    Neurological Research 02/1992; 14(2 Suppl):94-6. · 1.44 Impact Factor
  • D A Spriggs · J M Murdy · J M French · D Bates · O.F W James ·

    Age and Ageing 01/1992; 21(suppl 1). DOI:10.1093/ageing/21.suppl_1.P18-a · 3.64 Impact Factor

Publication Stats

4k Citations
242.12 Total Impact Points


  • 1996
    • University of Newcastle
      Newcastle, New South Wales, Australia
  • 1985-1996
    • Newcastle University
      • Institute for Ageing and Health
      Newcastle-on-Tyne, England, United Kingdom
  • 1989
    • Queen's University Belfast
      Béal Feirste, N Ireland, United Kingdom
  • 1982
    • The Newcastle upon Tyne Hospitals NHS Foundation Trust
      Newcastle-on-Tyne, England, United Kingdom
  • 1977
    • Gracie Square Hospital, New York, NY
      New York, New York, United States