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Dive into the research topics where John D. O’Sullivan is active.

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Featured researches published by John D. O’Sullivan.


Stroke | 2004

Impact of Premorbid Undernutrition on Outcome in Stroke Patients

James P. Davis; Andrew Wong; Philip J. Schluter; Robert D. Henderson; John D. O’Sullivan; Stephen J. Read

Background and Purpose— To assess the prevalence of premorbid undernutrition and its impact on outcomes 1 month after stroke. Methods— The study recruited from consecutive stroke admissions during a 10-month period. Premorbid nutritional status (using the subjective global assessment [SGA]), premorbid functioning (modified Rankin scale [MRS]), and stroke severity (National Institutes of Health Stroke Scale [NIHSS] score) were assessed at admission. The associations between premorbid nutritional status, poor outcome (defined as MRS ≥3), and mortality were examined before and after adjustment for confounding variables, including age, gender, stroke risk factors, stroke severity, and admission serum albumin. Results— Thirty of 185 patients were assessed as having undernutrition at admission. Significant unadjusted associations were observed between undernutrition and poor outcome (odds ratio [OR], 3.4; 95% CI, 1.3 to 8.7; P =0.01), and mortality (OR, 3.1, 95% CI, 1.3 to 7.7; P =0.02) at 1 month. NIHSS, age, and premorbid MRS were also significantly associated with poor outcomes. After adjustment for these factors, the effect size of associations remained important but not significant (poor outcome: OR, 2.4; 95% CI, 0.7 to 9.0, P =0.18; mortality: OR, 3.2; 95% CI, 1.0 to 10.4, P =0.05). Conclusions— Premorbid undernutrition, as assessed using the SGA, appears to be an independent predictor of poor stroke outcome. Stroke prevention strategies should target undernutrition in the population at risk for stroke to improve outcomes.


European Journal of Neurology | 2011

Improved language performance subsequent to low-frequency rTMS in patients with chronic non-fluent aphasia post-stroke

Caroline H. S. Barwood; Bruce E. Murdoch; Brooke-Mai Whelan; David Lloyd; Stephan Riek; John D. O’Sullivan; Alan Coulthard; Andrew Wong

Background:  Low‐frequency repetitive transcranial magnetic stimulation (rTMS) has emerged as a potential tool for neurorehabilitation and remediation of language in chronic non‐fluent aphasia post‐stroke. Inhibitory (1 Hz) rTMS has been applied to homologous language sites to facilitate behavioural language changes. Improvements in picture‐naming performance and speech output over time have been reported.


Brain Stimulation | 2012

Improved receptive and expressive language abilities in nonfluent aphasic stroke patients after application of rTMS: An open protocol case series

Caroline H. S. Barwood; Bruce E. Murdoch; Brooke-Mai Whelan; David Lloyd; Stephan Riek; John D. O’Sullivan; Alan Coulthard; Andrew Wong

BACKGROUND Repetitive transcranial magnetic stimulation (rTMS) has been identified as a potentially valuable tool for the rehabilitation of language impairment after left hemisphere (LH) stroke, in populations of persons with chronic aphasia. Applied to a homologue to Brocas area, rTMS is posited to modulate bilateral language networks, promoting measurable behavioral language change, in accordance with theories of transcallosal disinhibition arising from the damaged LH. OBJECTIVE/HYPOTHESIS The current investigation is an open-label study, presenting detailed case and group presentations on a population of seven nonfluent aphasic participants. Behavioral language performance is presented on expressive and receptive language measures up to 8 months after a 10-day protocol of 1 Hz stimulation. This research aims to provide longitudinal behavioral language outcomes for persons with aphasia, subsequent to rTMS and supplement previous studies to inform the clinical efficacy of rTMS. RESULTS In accordance with previous investigations, significant improvements in picture naming, spontaneous elicited speech and auditory comprehension were found. Time of testing was identified as a significant main effect. Significant improvements in picture naming accuracy and decreases in picture naming latency were also identified. The results demonstrate sustained language improvements up to 8 months subsequent to TMS application. CONCLUSIONS The results of this investigation are consistent with the findings of previous research studies, reporting behavioral language changes after rTMS in nonfluent aphasia. Additional evidence is provided to demonstrate that rTMS may facilitate retrieval mechanisms involved in picture naming.


Journal of Clinical Neuroscience | 2006

Circadian blood pressure variation after acute stroke

Jeyaraj D. Pandian; Andrew Wong; Douglas J. Lincoln; James P. Davis; Robert D. Henderson; John D. O’Sullivan; Stephen J. Read

We aimed to characterise the patterns of circadian blood pressure (BP) variation after acute stroke and determine whether any relationship exists between these patterns and stroke outcome. BP was recorded manually every 4 h for 48 h following acute stroke. Patients were classified according to the percentage fall in mean systolic BP (SBP) at night compared to during the day as: dippers (fall > or = 10-<20%); extreme dippers (> or = 20%); non-dippers (> or = 0-<10%); and reverse dippers (<0%, that is, a rise in mean nocturnal SBP compared to mean daytime SBP). One hundred and seventy-three stroke patients were included in the study (83 men, 90 women; mean age 74.3 years). Four patients (2.3%) were extreme dippers, 25 (14.5%) dippers, 80 (46.2%) non-dippers and 64 (36.9%) reverse dippers. There was a non-significant trend in the proportion of patients who were dead or dependent at 3 months in the extreme dipper (p=0.59) and reverse dipper (p=0.35) groups. Non-dipping and reverse-dipping were relatively common patterns of circadian BP variation seen in acute stroke patients. These patterns were not clearly associated with outcome.


Journal of Clinical Neuroscience | 2005

The effect of admission physiological variables on 30 day outcome after stroke

Andrew Wong; James P. Davis; Philip J. Schluter; Robert D. Henderson; John D. O’Sullivan; Stephen J. Read

INTRODUCTION Potentially modifiable physiological variables may influence stroke prognosis but their independence from modifiable factors remains unclear. METHODS Admission physiological measures (blood pressure, heart rate, temperature and blood glucose) and other unmodifiable factors were recorded from patients presenting within 48 hours of stroke. These variables were compared with the outcomes of death and death or dependency at 30 days in multivariate statistical models. RESULTS In the 186 patients included in the study, age, atrial fibrillation and the National Institutes of Health Stroke Score were identified as unmodifiable factors independently associated with death and death or dependency. After adjusting for these factors, none of the physiological variables were independently associated with death, while only diastolic blood pressure (DBP) > or = 90 mmHg was associated with death or dependency at 30 days (p = 0.02). CONCLUSIONS Except for elevated DBP, we found no independent associations between admission physiology and outcome at 30 days in an unselected stroke cohort. Future studies should look for associations in subgroups, or by analysing serial changes in physiology during the early post-stroke period.


Cerebrovascular Diseases | 2007

The Time Course and Determinants of Blood Pressure within the First 48 h after Ischemic Stroke

Andrew Wong; James P. Davis; Philip J. Schluter; Robert D. Henderson; John D. O’Sullivan; Stephen J. Read

Background and Purpose: Previous research suggests that blood pressure falls acutely after ischemic stroke. We aimed to further characterize this fall with a statistical technique that allows the application of regression techniques to serial blood pressure outcome data. Methods: In a prospectively recruited ischemic stroke cohort, systolic (SBP) and diastolic (DBP) blood pressure was recorded every 4 h until 48 h after stroke. Potential determinants of blood pressure, including stroke severity and acute infection, were also recorded. Mixed effects models were used to model serial blood pressure measurements over time, adjusted for significant determinants. Results: In 156 patients, SBP and DBP fell by 14.9 mm Hg (95% CI 6.2–22.6 mm Hg) and 6.2 mm Hg (95% CI 1.4–10.6 mm Hg), respectively, over the first 48 h after stroke. SBP was higher in patients with premorbid hypertension, a previous history of stroke or TIA, current alcohol use, increasing age, stroke of mild to moderate severity (NIHSS 3–13) and in patients treated with antihypertensives. SBP was lower in smokers. There was a progressive rise in SBP in patients with acute infection. No factors other than time were associated with DBP. Conclusions: The use of mixed effects models has identified a linear SBP and DBP fall over the first 48 h after stroke. The timing and magnitude of this fall should be accounted for in the design of future prognostic and intervention studies.


Clinical Gerontologist | 2017

Cognitive behavior therapy for anxiety in Parkinson’s disease: outcomes for patients and caregivers

N. Dissanayaka; Deidre Pye; Leander Mitchell; Gerard J. Byrne; John D. O’Sullivan; R. Marsh; Nancy A. Pachana

ABSTRACT Objective: Anxiety negatively impacts the quality of life of Parkinson’s disease (PD) patients and caregivers. Despite high prevalence, there is a paucity of trials investigating effective treatments for anxiety in PD. This uncontrolled study investigated the use of a manualized and tailored Cognitive Behavior Therapy (CBT) for anxiety in PD. Methods: Participants completed 6 weekly CBT sessions. Pre-, post- and follow-up (3 and 6 months) assessments were made. Change in outcomes were analysed using t-tests and Reliability Change Index. Of 17 PD patients who agreed to CBT, 12 completed the intervention. Results: This study showed a significant reduction in Hamilton Anxiety Rating Scale scores in PD immediately post CBT (t(11) = 3.59, p < .01), maintained at 3-month (t(8) = 2.83, p = .02) and 6-month (t(7) = 2.07, p = .04) follow-up. A reduction in caregiver burden (t(11) = 2.68, p = .03) was observed post intervention. Improvements in motor disability (t(11) = 2.41, p = .04) and cognitive scores (t(11) = −2.92, p = .01) were also observed post intervention and at follow-up. Conclusions: Tailored CBT can be used to treat anxiety in PD. Clinical Implications: This study provides preliminary evidence suggesting that tailored CBT reduces anxiety in PD with persisting benefits, and lowers caregiver burden.


Journal of Clinical Neuroscience | 2006

Charles Dickens: The man, medicine, and movement disorders

Kerrie L. Schoffer; John D. O’Sullivan

Nineteenth-century Victorian novelists played an important role in developing our understanding of medicine and illness. With the eye of an expert clinician, Charles Dickens provided several detailed accounts of movement disorders in his literary works, many of which predated medical descriptions. His gift for eloquence, imagery, and precision attest not only to the importance of careful clinical observation, but also provide an insightful and entertaining perspective on movement disorders for modern students of neuroscience.


Journal of Clinical Neuroscience | 2007

Unusual triggers for stroke

Jeyaraj D. Pandian; Robert Perel; Robert D. Henderson; John D. O’Sullivan; Stephen J. Read

We describe three young patients who had strokes in an unusual setting; two patients during coitus and 1 patient after a bout of laughter. Two patients had a patent foramen ovale and one patient developed vertebral artery dissection during coitus. The underlying stroke mechanisms in the three patients are discussed. These cases highlight the importance of questioning the events preceding stroke onset.


Journal of Clinical Neuroscience | 2014

Vertebrobasilar dissections: case series comparing patients with and without dissecting aneurysms

Monica S. Badve; Robert D. Henderson; John D. O’Sullivan; Andrew Wong; Ken Mitchell; Alan Coulthard; Stephen J. Read

Vertebrobasilar dissections are being increasingly diagnosed due to better awareness and increased availability of modern imaging techniques of the intracranial and extracranial arteries. The clinical presentation and outcome in patients with vertebrobasilar dissections may be complicated by dissecting aneurysms. The aim of this retrospective study was to compare the clinical profile of patients with vertebrobasilar dissections with and without dissecting aneurysms, and to determine predisposing factors to the development of aneurysms. Thirty patients (19 [63%] male; median age 44.5 years) were identified. The patients were divided into two groups, an aneurysmal dissection group with seven patients and a non-aneurysmal dissection group with 23 patients. Eight (27%) patients presented with dissection after trivial trauma, three (10%) following high-speed vehicular trauma, two (7%) were associated with infection, but most (57%) were apparently spontaneous. Migraine with aura (p=0.008) and female sex (p=0.03) were observed more frequently in the aneurysmal dissection group. Though vascular risk factors other than hypertension and atrial fibrillation were seen in a greater percentage of patients in the non-aneurysmal dissection group, this was not statistically significant. Patients were treated with antiplatelet agents (n=8) or warfarin (n=13) or underwent an endovascular intervention (n=6). Post-discharge data were available in 19 patients, of whom 14 (74%) were independent at a median follow-up of 4 months. Female sex and migraine with aura may predispose to the formation of acute dissecting aneurysms and this requires further research. Larger, prospective studies are required to ascertain epidemiologic and etiologic factors predisposing patients to the development of both intracranial and extracranial dissecting aneurysms in the vertebrobasilar circulation.

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N. Dissanayaka

University of Queensland

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R. Marsh

University of Queensland

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Robert D. Henderson

Royal Brisbane and Women's Hospital

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Stephen J. Read

Royal Brisbane and Women's Hospital

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Andrew Wong

Royal Brisbane and Women's Hospital

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