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Augustyniak H, Gannon J, Mohr D, O'steen L, Anderson CS, Finalley T, Greenwalt JC. Improving Patient Compliance with Vaginal Dilator Therapy by Implementation of Sexual Health Consult in Gynecologic Malignancies after Radiation Therapy. Int J Radiat Oncol Biol Phys 2023; 117:e218-e219. [PMID: 37784893 DOI: 10.1016/j.ijrobp.2023.06.1117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Typical vaginal dilator therapy (VDT) compliance falls short at approximately 30% of patients in reported studies, which could lead to vaginal stenosis (VS) in as high as 88% of patients who undergo radiation therapy (RT) for gynecologic malignancies. In an ongoing effort to improve adherence to VDT aimed to prevent vaginal stenosis post pelvic and vaginal RT, a prospective study was implemented to assess the feasibility and the impact on vaginal dilator therapy adherence when implementing a consult with the oncology women's sexual health clinic following the completion of radiation therapy. MATERIALS/METHODS This was a single institution, prospective analysis and feasibility study that included patients diagnosed with a gynecologic cancer who were treated with RT to the pelvic and or vaginal tissues. Using purposive sampling, the treating radiation oncologists identified eligible patients and referred them to the oncology women's sexual health clinic for consult four to six weeks status post completion of RT in a six-month period. A post treatment survey was conducted via a telephone interview 12 weeks after the sexual health clinic initial consult to assess vaginal dilator therapy compliance. Descriptive statistics were calculated. RESULTS Pre-intervention retrospective data analysis revealed poor compliance to VDT with only 3 of 40 (7.5%) patients judged as compliant. Post-intervention, 30 of 37 (81.1%) patients in the sample were judged compliant. The adherence rate in the post-intervention group was significantly higher (Fisher's Exact Test two-tailed p-value < 0.0001). With confidence of 95%, the proportion of the potential population that would adhere post intervention was between 68.5% and 93.7%. Sociodemographic and clinical characteristics did not have a statistically significant correlation with VDT compliance. CONCLUSION Implementing a referral to an oncology women's sexual health clinic at the completion of RT for the sample population is feasible. Our project demonstrates that instituting this new sexual health clinic may have a large, positive impact on patient compliance to vaginal dilator therapy. More importantly, this may lead to decrease incidences of vaginal stenosis and improvement in patient health outcomes and quality of life (QoL).
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Affiliation(s)
| | - J Gannon
- University of Florida, Gainesville, FL
| | - D Mohr
- University of North Florida, Jacksonville, FL
| | - L O'steen
- Baptist MD Anderson, Jacksonville, FL
| | - C S Anderson
- Baptist MD Anderson Cancer Center, Jacksonville, FL
| | - T Finalley
- Baptist MD Anderson Cancer Center, Jacksonville, FL
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Phan HT, Gall SL, Blizzard CL, Lannin NA, Thrift AG, Anderson CS, Kim J, Grimley RS, Castley HC, Kilkenny MF, Cadilhac DA. Sex differences in quality of life after stroke were explained by patient factors, not clinical care: evidence from the Australian Stroke Clinical Registry. Eur J Neurol 2020; 28:469-478. [PMID: 32920917 DOI: 10.1111/ene.14531] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 09/04/2020] [Accepted: 09/05/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND PURPOSE Women may receive stroke care less often than men. We examined the contribution of clinical care on sex differences and health-related quality of life (HRQoL) after stroke. METHODS We included first-ever strokes registered in the Australian Stroke Clinical Registry (2010-2014) with HRQoL assessed between 90 and 180 days after onset (EQ-5D-3L instrument) that were linked to hospital administrative data (up to 2013). Study factors included sociodemographics, comorbidities, walking ability on admission (stroke severity proxy) and clinical care (e.g. stroke unit care). Responses to the EQ-5D-3L were transformed into a total utility value (-0.516 'worse than death' to 1 'best' health). Quantile regression models, adjusted for confounding factors, were used to determine median differences (MD) in utility scores by sex. RESULTS Approximately 60% (6852/11 418) of stroke survivors had an EQ-5D-3L assessment (median 139 days; 44% female). Compared with men, women were older (median age 77.1 years vs. men 71.2 years) and fewer could walk on admission (37.9% vs. men 46.1%, P < 0.001). Women had lower utility values than men, and the difference was explained by age and stroke severity, but not clinical care [MDadjusted = -0.039, 95% confidence interval: -0.056, -0.021]. Poorer HRQoL was observed in younger men (aged <65 years), particularly those with more comorbidities, and in older women (aged ≥75 years). CONCLUSIONS Stroke severity and comorbidities contribute to the poorer HRQoL in young men and older women. Further studies are needed to understand age-sex interaction to better inform treatments for different subgroups and ensure evidence-based treatments to reduce the severity of stroke are prioritized.
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Affiliation(s)
- H T Phan
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.,Department of Public Health Management, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam.,Stroke and Ageing Research, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
| | - S L Gall
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia.,Stroke and Ageing Research, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
| | - C L Blizzard
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
| | - N A Lannin
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia.,Alfred Health, Melbourne, Victoria, Australia
| | - A G Thrift
- Stroke and Ageing Research, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
| | - C S Anderson
- Faculty of Medicine, The George Institute for Global Health, The University of New South Wales, Sydney, New South Wales, Australia
| | - J Kim
- Stroke and Ageing Research, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia
| | - R S Grimley
- Stroke and Ageing Research, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia.,School of Medicine, Griffith University, Birtinya, Queensland, Australia
| | - H C Castley
- Neurology Department, Royal Hobart Hospital, Hobart, Tasmania, Australia
| | - M F Kilkenny
- Stroke and Ageing Research, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia.,Stroke Theme, The Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
| | - D A Cadilhac
- Stroke and Ageing Research, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia.,Stroke Theme, The Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
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Lindley RI, Anderson CS, Billot L, Forster A, Hackett ML, Harvey LA, Jan S, Li Q, Liu H, Langhorne P, Maulik PK, Murthy GVS, Walker MF, Pandian JD, Alim M, Felix C, Syrigapu A, Tugnawat DK, Verma SJ, Shamanna BR, Hankey G, Thrift A, Bernhardt J, Mehndiratta MM, Jeyaseelan L, Donnelly P, Byrne D, Steley S, Santhosh V, Chilappagari S, Mysore J, Roy J, Padma MV, John L, Aaron S, Borah NC, Vijaya P, Kaul S, Khurana D, Sylaja PN, Halprashanth DS, Madhusudhan BK, Nambiar V, Sureshbabu S, Khanna MC, Narang GS, Chakraborty D, Chakraborty SS, Biswas B, Kaura S, Koundal H, Singh P, Andrias A, Thambu DS, Ramya I, George J, Prabhakar AT, Kirubakaran P, Anbalagan P, Ghose M, Bordoloi K, Gohain P, Reddy NM, Reddy KV, Rao TNM, Alladi S, Jalapu VRR, Manchireddy K, Rajan A, Mehta S, Katoch C, Das B, Jangir A, Kaur T, Sreedharan S, Sivasambath S, Dinesh S, Shibi BS, Thangaraj A, Karunanithi A, Sulaiman SMS, Dehingia K, Das K, Nandini C, Thomas NJ, Dhanya TS, Thomas N, Krishna R, Aneesh V, Krishna R, Khullar S, Thouman S, Sebastian I. Family-led rehabilitation after stroke in India (ATTEND): a randomised controlled trial. Lancet 2017; 390:588-599. [PMID: 28666682 DOI: 10.1016/s0140-6736(17)31447-2] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/17/2017] [Accepted: 04/04/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND Most people with stroke in India have no access to organised rehabilitation services. The effectiveness of training family members to provide stroke rehabilitation is uncertain. Our primary objective was to determine whether family-led stroke rehabilitation, initiated in hospital and continued at home, would be superior to usual care in a low-resource setting. METHODS The Family-led Rehabilitation after Stroke in India (ATTEND) trial was a prospectively randomised open trial with blinded endpoint done across 14 hospitals in India. Patients aged 18 years or older who had had a stroke within the past month, had residual disability and reasonable expectation of survival, and who had an informal family-nominated caregiver were randomly assigned to intervention or usual care by site coordinators using a secure web-based system with minimisation by site and stroke severity. The family members of participants in the intervention group received additional structured rehabilitation training-including information provision, joint goal setting, carer training, and task-specific training-that was started in hospital and continued at home for up to 2 months. The primary outcome was death or dependency at 6 months, defined by scores 3-6 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]) as assessed by masked observers. Analyses were by intention to treat. This trial is registered with Clinical Trials Registry-India (CTRI/2013/04/003557), Australian New Zealand Clinical Trials Registry (ACTRN12613000078752), and Universal Trial Number (U1111-1138-6707). FINDINGS Between Jan 13, 2014, and Feb 12, 2016, 1250 patients were randomly assigned to intervention (n=623) or control (n=627) groups. 33 patients were lost to follow-up (14 intervention, 19 control) and five patients withdrew (two intervention, three control). At 6 months, 285 (47%) of 607 patients in the intervention group and 287 (47%) of 605 controls were dead or dependent (odds ratio 0·98, 95% CI 0·78-1·23, p=0·87). 72 (12%) patients in the intervention group and 86 (14%) in the control group died (p=0·27), and we observed no difference in rehospitalisation (89 [14%]patients in the intervention group vs 82 [13%] in the control group; p=0·56). We also found no difference in total non-fatal events (112 events in 82 [13%] intervention patients vs 110 events in 79 [13%] control patients; p=0·80). INTERPRETATION Although task shifting is an attractive solution for health-care sustainability, our results do not support investment in new stroke rehabilitation services that shift tasks to family caregivers, unless new evidence emerges. A future avenue of research should be to investigate the effects of task shifting to health-care assistants or team-based community care. FUNDING The National Health and Medical Research Council of Australia.
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Benedetti LR, Holder JP, Perkins M, Brown CG, Anderson CS, Allen FV, Petre RB, Hargrove D, Glenn SM, Simanovskaia N, Bradley DK, Bell P. Advances in x-ray framing cameras at the National Ignition Facility to improve quantitative precision in x-ray imaging. Rev Sci Instrum 2016; 87:023511. [PMID: 26931853 DOI: 10.1063/1.4941754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 01/25/2016] [Indexed: 06/05/2023]
Abstract
We describe an experimental method to measure the gate profile of an x-ray framing camera and to determine several important functional parameters: relative gain (between strips), relative gain droop (within each strip), gate propagation velocity, gate width, and actual inter-strip timing. Several of these parameters cannot be measured accurately by any other technique. This method is then used to document cross talk-induced gain variations and artifacts created by radiation that arrives before the framing camera is actively amplifying x-rays. Electromagnetic cross talk can cause relative gains to vary significantly as inter-strip timing is varied. This imposes a stringent requirement for gain calibration. If radiation arrives before a framing camera is triggered, it can cause an artifact that manifests as a high-intensity, spatially varying background signal. We have developed a device that can be added to the framing camera head to prevent these artifacts.
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Affiliation(s)
- L R Benedetti
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - J P Holder
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - M Perkins
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - C G Brown
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - C S Anderson
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - F V Allen
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - R B Petre
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - D Hargrove
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - S M Glenn
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - N Simanovskaia
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - D K Bradley
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - P Bell
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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Sato S, Heeley E, Arima H, Delcourt C, Hirakawa Y, Pamidimukkala V, Li Z, Tao Q, Xu Y, Hennerici MG, Robinson T, Tzourio C, Lindley RI, Chalmers J, Anderson CS, Anderson CS, Huang Y, Wang JG, Arima H, Neal B, Peng B, Heeley E, Skulina C, Parsons MW, Kim JS, Tao QL, Li YC, Jiang JD, Tai LW, Zhang LJ, Xu E, Cheng Y, Heritier S, Morgenstern LB, Chalmers J. Higher mortality in patients with right hemispheric intracerebral haemorrhage: INTERACT1 and 2. J Neurol Neurosurg Psychiatry 2015; 86:1319-23. [PMID: 25589782 DOI: 10.1136/jnnp-2014-309870] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 12/22/2014] [Indexed: 11/03/2022]
Abstract
BACKGROUND AND PURPOSE Controversy exists over the prognostic significance of the affected hemisphere in stroke. We aimed to determine the relationship between laterality of acute intracerebral haemorrhage (ICH) and poor clinical outcomes. METHODS A subsidiary analysis of the INTERACT Pilot and INTERACT2 studies--randomised controlled trials of patients with spontaneous acute ICH with elevated systolic blood pressure (BP), randomly assigned to intensive (target systolic BP <140 mm Hg) or guideline-based (<180 mm Hg) BP management. Outcomes were the combined and separate end points of death and major disability (modified Rankin scale (mRS) scores of 3-6, 6 and 3-5, respectively) at 90 days. RESULTS A total of 2708 patients had supratentorial/hemispheric ICH and information on mRS at 90 days. Patients with right hemispheric ICH (1327, 49%) had a higher risk of death at 90 days compared to those with left hemispheric ICH after adjustment for potential confounding variables (OR, 1.77 (95% CI 1.33 to 2.37)). There were no differences between patients with right and left hemispheric ICH regarding the combined end point of death or major disability or major disability in the multivariable-adjusted models (1.07 (0.89 to 1.29) and 0.85 (0.72 to 1.01), respectively). CONCLUSIONS Right hemispheric lesion was associated with increased risk of death in patients with acute ICH. The laterality of the ICH does not appear to affect the level of disability in survivors. TRIAL REGISTRATION NUMBER URL: http://www.clinicaltrials.gov. Unique identifier: NCT00226096 and NCT00716079.
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Affiliation(s)
- Shoichiro Sato
- The George Institute for Global Health, the University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Emma Heeley
- The George Institute for Global Health, the University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Hisatomi Arima
- The George Institute for Global Health, the University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Candice Delcourt
- The George Institute for Global Health, the University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Yoichiro Hirakawa
- The George Institute for Global Health, the University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | | | - Zhendong Li
- Department of Neurology, The Fifth Affiliated Hospital, Sun Yat-Sen University, Guangdong, China
| | - Qingling Tao
- Department of Neurology, Chang Ning District Central Hospital, Shanghai, China
| | - Yuehong Xu
- Department of Neurology, Shijiazhuang 260 Hospital, Hebei, China
| | - Michael G Hennerici
- Department of Neurology, University of Heidelberg UMM Mannheim, Mannheim, Germany
| | - Thompson Robinson
- Department of Cardiovascular Sciences, and NIHR Biomedical Research Unit for Cardiovascular Diseases, University of Leicester, Leicester, UK
| | | | - Richard I Lindley
- The George Institute for Global Health, the University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - John Chalmers
- The George Institute for Global Health, the University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Craig S Anderson
- The George Institute for Global Health, the University of Sydney and Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
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Rymer MM, Anderson CS, Harada M, Jarosz J, Ma N, Rowley HA, Summers D, Tastula K, Williams O, Bornstein NM. Stroke service: how can we improve and measure outcomes? Consensus summary from a global stroke forum. Acta Neurol Scand 2014; 130:73-80. [PMID: 24796345 DOI: 10.1111/ane.12256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2014] [Indexed: 11/27/2022]
Abstract
The success of acute stroke treatment is first and foremost time-dependent, and the need for improvement in acute stroke management is demonstrated by the fact that only a minority of patients gain access to treatment - in particular, intravenous recombinant tissue plasminogen activator (IV tPA) - within the necessary time window. Standards of acute stroke care vary widely both regionally and nationally; consequently, various healthcare organizations have undertaken initiatives to measure and improve quality of care. To date, most quality measures have been process-based, focusing primarily on metrics of patient care in the acute hospital-based setting (e.g., time to recombinant tPA administration). Therefore, there remains a need for metrics designed to assess how improvements in process translate into patient outcomes. A global forum was convened to share best practice and provide consensus recommendations on core metrics for measuring improvements in access to care and patient outcomes. Recommendations for core metrics of patient outcomes include hospital-based outcomes (e.g., neurological status at 24 h, ambulatory status at discharge) and post-discharge outcomes (e.g., modified Rankin Scale score at 30 and/or 90 days). Recommendations for best practice relating to aspects of people, process, and technology involved in the stroke treatment pathway that may help provide improvements in these core outcome measures are also outlined.
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Affiliation(s)
- M. M. Rymer
- The University of Kansas Hospital; Kansas City KS USA
| | - C. S. Anderson
- The George Institute for Global Health; Royal Prince Alfred Hospital; University of Sydney; Sydney NSW Australia
| | - M. Harada
- University of Tokushima; Tokushima Japan
| | | | - N. Ma
- Beijing Tiantan Hospital; Beijing China
| | - H. A. Rowley
- School of Medicine and Public Health; University of Wisconsin; Madison WI USA
| | - D. Summers
- St Luke's Neuroscience Institute; Kansas City MO USA
| | - K. Tastula
- Royal Prince Alfred Hospital; Sydney NSW Australia
| | | | - N. M. Bornstein
- Tel-Aviv Medical Center; Tel-Aviv University; Tel-Aviv Israel
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Stapf C, Heeley E, Delcourt C, Arima H, Chalmers J, Anderson CS. Abstract 180: The Relation of Timing and Degree of Blood Pressure Control with Hematoma Growth - Secondary Analysis of The Interact2 Trial. Stroke 2014. [DOI: 10.1161/str.45.suppl_1.180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background:
Acute blood pressure (BP) lowering therapy has shown clinical benefit in patients with acute intracerebral hemorrhage (ICH), but the effect of timing and degree of BP control on ICH growth has received less study.
Methods:
Among the INTERACT2 participants (N=2839) with acute ICH allocated either to intensive BP lowering therapy (IT, systolic target <140mmHg) or standard BP treatment (ST), CT brain imaging at baseline and 24 hours were centrally analysed in a subset of 491 (34%) in the IT and 473 (34%) in the ST groups.
Results:
Absolute mean ICH growth was lower in patients reaching BP target in <1h from randomization (1.7ml), as compared to those reaching target in 1-6h (4.2ml), and >6h (4.6ml, p=0.04). Hematoma growth was particularly high (14.4ml, 95%CI:10.0-18.8) in patients admitted with systolic BP>160mmHg who achieved <10mmHg systolic BP lowering over 24h, as compared to those achieving 10-20mmHg (3.7ml, 95%CI:0.3-7.1) or 20-30mmHg BP reduction (2.7ml, 95%CI:1.1-4.3); p<0.01). Patients maintaining target BP at 0-2 measurements over 24h had higher absolute volume increase (3.6ml; 95%CI:1.8-5.4) as compared to those who maintained target BP over 3-4 (1.6ml, 95%CI:-0.3-3.5), or 5-8 measurements (0.4ml, 95%CI:-1.7-2.4; p=0.01).
Conclusion:
These findings suggest that early and sustained BP control have favorable effects on hematoma growth. This reinforces the principle for patients with acute ICH to receive BP lowering therapy as early as possible and to achieve a lower level of systolic BP for the most favorable outcome.
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Affiliation(s)
- C. Stapf
- APHP - Hôpital Lariboisière, Paris, France
| | - E. Heeley
- The George Institute of Global Health, Sydney, Australia
| | - C. Delcourt
- The George Institute of Global Health, Sydney, Australia
| | - H. Arima
- The George Institute of Global Health, Sydney, Australia
| | - J. Chalmers
- The George Institute of Global Health, Sydney, Australia
| | - C. S Anderson
- The George Institute of Global Health, Sydney, Australia
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Delcourt C, Huang Y, Arima H, Chalmers J, Davis SM, Heeley EL, Wang J, Parsons MW, Liu G, Anderson CS. Hematoma growth and outcomes in intracerebral hemorrhage: The INTERACT1 study. Neurology 2012; 79:314-9. [DOI: 10.1212/wnl.0b013e318260cbba] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Arima H, Wang JG, Huang Y, Heeley E, Skulina C, Parsons MW, Peng B, Li Q, Su S, Tao QL, Li YC, Jiang JD, Tai LW, Zhang JL, Xu E, Cheng Y, Morgenstern LB, Chalmers J, Anderson CS. Significance of perihematomal edema in acute intracerebral hemorrhage: the INTERACT trial. Neurology 2009; 73:1963-8. [PMID: 19996072 DOI: 10.1212/wnl.0b013e3181c55ed3] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Uncertainty surrounds the effects of cerebral edema on outcomes in intracerebral hemorrhage (ICH). METHODS We used data from the INTERACT trial to determine the predictors and prognostic significance of "perihematomal" edema over 72 hours after ICH. INTERACT included 404 patients with CT-confirmed ICH and elevated systolic blood pressure (BP) (150-220 mm Hg) who had the capacity to commence BP lowering treatment within 6 hours of ICH. Baseline and repeat CT (24 and 72 hours) were performed using standardized techniques, with digital images analyzed centrally. Predictors of growth in edema were determined using generalized estimating equations, and its effects on clinical outcomes were estimated using a logistic regression model. RESULTS Overall, 270 patients had 3 sequential CT scans available for analyses. At baseline, there was a highly significant correlation between hematoma and perihematomal edema volumes (r(2) = 0.45). Lower systolic BP and baseline hematoma volume were independently associated with absolute increase in perihematomal edema volume. History of hypertension, baseline hematoma volume, and earlier time from onset to CT were independently associated with relative increase in edema volume. Both absolute and relative increases in perihematomal edema growth were significantly associated with death or dependency at 90 days after adjustment for age, gender, and randomized treatment, but not when additionally adjusted for baseline hematoma volume. CONCLUSIONS The degree of, and growth in, perihematomal edema are strongly related to the size of the underlying hematoma of acute intracerebral hemorrhage, and do not appear to have a major independent effect in determining the outcome from this condition.
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Affiliation(s)
- H Arima
- The George Institute for International Health, Royal Prince Alfred Hospital and the University of Sydney, Sydney, Australia
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Wermer MJH, van der Schaaf IC, Van Nunen P, Bossuyt PMM, Anderson CS, Rinkel GJE. Psychosocial Impact of Screening for Intracranial Aneurysms in Relatives With Familial Subarachnoid Hemorrhage. Stroke 2005; 36:836-40. [PMID: 15746461 DOI: 10.1161/01.str.0000158906.79898.3a] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
In families with ≥2 relatives with intracranial aneurysms (IAs), screening for IAs in asymptomatic first-degree relatives is often recommended. We assessed the long-term psychosocial impact of such screening.
Methods—
We identified all persons with IA (screen-positives) and matched them for age and sex with 2 controls without IA (screen-negatives) from hospital-based registers of familial IA. Persons underwent telephone interviews using questionnaires that covered the areas of psychosocial impact of screening, health-related quality of life (HRQoL), and mood. Data were compared between screen-positives and screen-negatives, and with reference populations.
Results—
Overall, 105 persons from 33 families with IA were included, of whom 35 were screen-positive and 70 were screen-negative. Of the screen-positives, 12 (44%) had reduced their work and 23 (66%) had experienced changes in ≥1 area of independence, self-esteem, future outlook, or personal relationships. In contrast, only 1 (2%) screen-negative person had stopped working and 12 (17%) others had experienced changes in their self-esteem, future outlook, or relationships. Screen-positives had lower HRQoL compared with screen-negatives and the reference population, whereas both screen groups had higher mean depression scores than the reference population. Despite these effects, only 3 persons regretted participating in screening.
Conclusion—
Although screening for IA is an important preventative strategy in high-risk individuals, it is associated with considerable psychosocial effects, both positive and negative. Greater awareness of such outcomes, and appropriate intervention where necessary, would appear to be a necessary component of IA screening programs.
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Affiliation(s)
- M J H Wermer
- Department of Neurology, University Medical Center Utrecht, The Netherlands.
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Abstract
BACKGROUND Antidepressants may be useful in the treatment of abnormal crying associated with stroke. OBJECTIVES To determine whether pharmaceutical treatment reduces the frequency of emotional displays in people who suffer from emotionalism after stroke. SEARCH STRATEGY We searched the Cochrane Stroke Group Trials Register (last searched June 2003). In addition we searched the following electronic databases: Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3 2002), MEDLINE (1966 to September 2002), EMBASE (1980 to September 2002), CINAHL (1982 to September 2002), PsychINFO (1967 to September 2002), Applied Science and Technology Plus (1986 to September 2002), Arts and Humanities Index (1991 to September 2002), Biological Abstracts (1969 to September 2002), General Science Plus (1994 to September 2002), Science Citation Index (1992 to September 2002), Social Sciences Citation Index (1991 to September 2002), and Sociofile (1974 to September 2002). We searched reference lists from relevant articles and textbooks, and contacted authors of known studies and pharmaceutical companies who manufacture psychotropic medications. SELECTION CRITERIA Randomised and quasi-randomised controlled trials, comparing psychotropic medication to placebo, in people with stroke and emotionalism (also known as emotional lability or pathological crying and laughing). DATA COLLECTION AND ANALYSIS Data were obtained on people who no longer met criteria for emotionalism, as defined in studies, and on reduction in frequency of crying at the end of treatment. Data were not pooled because of the multiplicity of definitions and outcome measures. MAIN RESULTS Five trials involving 103 participants were included. Four trials showed large effects of treatment: 50% reduction in emotionalism, improvements (reduction) in the frequency of compulsive laughter, and lower (better) scores on the Pathological Laughter and Crying scale. The confidence intervals were wide, however, indicating that treatment may have had only a small positive effect, or even a small negative effect (in one trial). Subgroup analysis was not performed due to the multiple methods of assessment of emotionalism within and between trials. Only one study systematically recorded and reported adverse events; no discernible difference was seen between groups. Participants allocated active treatment were more likely to leave early from trials. REVIEWERS' CONCLUSIONS Antidepressants can reduce the frequency and severity of crying or laughing episodes. The effect do not seem specific to one drug or class of drugs. However, our conclusions must be qualified by several methodological deficiencies in the studies. More reliable data are required before recommendations can be made about the treatment of post-stroke emotionalism.
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Abstract
BACKGROUND Depressive and anxiety disorders following stroke are often undiagnosed or inadequately treated. This may reflect difficulties with the diagnosis of abnormal mood among older people with stroke-related disability, but may also reflect uncertainty about the effectiveness of such therapies in this setting. OBJECTIVES To determine whether pharmacological, psychological, or electroconvulsive treatment (ECT) of depression in patients with stroke can improve outcome. SEARCH STRATEGY The Cochrane Stroke Group Trials Register (last searched June 2003). The Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2002), MEDLINE (1966 to September 2002), EMBASE (1980 to September 2002), CINAHL (1982 to September 2002), PsychINFO (1967 to September 2002), Applied Science and Technology Plus (1986 to September 2002), Arts and Humanities Index (1991 to September 2002), Biological Abstracts (1969 to September 2002), General Science Plus (1994 to September 2002), Science Citation Index (1992 to September 2002), Social Sciences Citation Index (1991 to September 2002), and Sociofile (1974 to September 2002). Reference lists from relevant articles and textbooks were searched, and authors of known studies and pharmaceutical companies who manufacture psychotropic medications were contacted. SELECTION CRITERIA Randomised and quasi-randomised controlled trials comparing different types of pharmaceutical agents with placebo, or various forms of psychotherapy with standard care (or attention control), in patients with recent, clinically diagnosed, acute stroke, where treatment was explicitly intended of treat depression. DATA COLLECTION AND ANALYSIS Primary analyses focussed on the prevalence of diagnosable depressive disorder at the end of treatment. Secondary outcomes included depression or mood scores on standard scales, disability or physical function, death, recurrent stroke, and adverse effects. We did not pool the data for summary scores. We performed meta-analysis for only some binary endpoints and data on adverse events. MAIN RESULTS Nine trials, with 780 participants, were included in the review. Data were available for seven trials of pharmaceutical agents, and two trials of psychotherapy. There were no trials of ECT. The analyses were complicated by the lack of standardised diagnostic and outcome criteria, and differing analytic methods. There was no strong evidence of benefit of either pharmacotherapy or psychotherapy in terms of a complete remission of depression following stroke. There was evidence of a reduction (improvement) in scores on depression rating scales, and an increase in the proportion of participants with anxiety at the end of follow up. REVIEWERS' CONCLUSIONS This review found no evidence to support the routine use of pharmacotherapeutic or psychotherapeutic treatment for depression after stroke. More research is required before recommendations can be made about the most appropriate management of depression following stroke.
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Affiliation(s)
- M L Hackett
- Clinical Trials Research Unit, University of Auckland, Private Bag 92019, Auckland, New Zealand
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13
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Abstract
BACKGROUND Abnormal mood is an important consequence of stroke and may affect recovery and outcome. However, depression and anxiety are often not detected or inadequately treated. This may in part be due to doubts about whether anti-depressant treatments commenced early after the onset of stroke will prevent depression and improve outcome. OBJECTIVES To determine if pharmaceutical or psychological interventions can prevent the onset of depression, including depressive illness and abnormal mood, and improve physical and psychological outcomes, in patients with stroke. SEARCH STRATEGY We searched the Cochrane Stroke Group trials register (June 2003). In addition we searched the following electronic databases: Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 3, 2002), MEDLINE (1966 to September 2002), EMBASE (1980 to September 2002), CINAHL (1982 to September 2002), PsychINFO (1967 to September 2002), Applied Science and Technology Plus (1986 to September 2002), Arts and Humanities Index (1991 to September 2002), Biological Abstracts (1969 to September 2002), General Science Plus (1994 to September 2002), Science Citation Index (1992 to September 2002), Social Sciences Citation Index (1991 to September 2002), and Sociofile (1974 to September 2002). Reference lists from relevant articles and textbooks were searched, and authors of known studies and pharmaceutical companies who manufacture psychotropic medications were contacted. SELECTION CRITERIA Randomised and quasi-randomised controlled trials comparing different types of pharmaceutical agents (eg selective serotonin reuptake inhibitors) with placebo, or various forms of psychotherapy against standard care (or attention control), in patients with a recent clinical diagnosis of stroke, where the treatment was undertaken with the explicit intention of preventing depression. DATA COLLECTION AND ANALYSIS The primary analyses focussed on the proportion of patients who met the standard diagnostic criteria for depression applied in the trials at the end of follow-up. Secondary outcomes included depression or mood scores on standard scales, disability or physical function, death, recurrent stroke, and adverse effects. MAIN RESULTS Twelve trials involving 1245 participants were included in the review. Data were available for nine trials (11 comparisons) involving different pharmaceutical agents, and three trials of psychotherapy. The time from stroke onset to entry ranged from a few hours to six months, but most patients were recruited within one month of acute stroke. The duration of treatments ranged from two weeks to one year. There was no clear effect of pharmacological therapy on the prevention of depression or on other measures. A significant improvement in mood was evident for psychotherapy, but this treatment effect was small and from a single trial. There was no effect on diagnosed depression. REVIEWERS' CONCLUSIONS This review identified a small but significant effect of psychotherapy on improving mood, but no effect of either pharmacotherapy or psychotherapy on the prevention of depressive illness, disability, or other outcomes. More evidence is therefore required before any recommendations can be made about the routine use of such treatments to improve recovery after stroke.
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Abstract
OBJECTIVES To highlight and discuss thyrotoxicosis after lithium withdrawal as a potential complication of lithium therapy for bipolar disorder. CASE REPORTS Both patients presented developed thyrotoxicosis, the first patient after stopping the lithium completely, and the second patient after a reduction in the lithium dose. CONCLUSIONS Clinicians should be alert to the possibility of thyrotoxicosis emerging when lithium is being completely or partially withdrawn. Such withdrawal could unmask a latent hyperthyroidism.
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Affiliation(s)
- C D Carmaciu
- Mental Health Department, Clacton and District Hospital, Clacton on Sea, Essex, UK.
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15
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Abstract
The aim of the present meta-analysis was to determine a temporal pattern of occurrence of subarachnoid haemorrhage (SAH). A MEDLINE 1966-2001 and EMBASE (1980-2001) literature search and hand search of relevant references were performed for population-based incidence studies that reported the time of SAH occurrence. Data from all identified relevant studies were combined into a pooled rate ratio (RR), with corresponding 95% confidence intervals (CI) using the Mantel-Haenszel method. Overall, eight population-based studies were included in the analysis. A total of 2533 first-ever cases of SAH were reported in the studies identified. Risk of SAH occurrence was the highest in the period between 6 am and 12 am (RR = 3.19; 95% CI 3.03-3.36; early morning as a reference variable) and between 12 p.m. and 6 p.m. (RR = 2.63; 95% CI 2.47-2.80), in winter and spring (RR = 1.10; 95% CI: 1.02-1.17; and RR = 1.07; 95% CI: 1.01-1.13, respectively; summer as a reference variable) and on Sunday (RR = 1.22; 95% CI 1.09-1.37; Monday as a reference variable). The evidence suggests that occurrence of SAH exhibits a seasonal (winter and spring) peak, diurnal (late morning peak) and daily (Sunday peak) pattern. It is suggested that the occurrence of some major acute vascular events (total ischaemic strokes, intracerebral haemorrhage and myocardial infarction) may be influenced by common triggering factors.
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Affiliation(s)
- V L Feigin
- Clinical Trials Research Unit, Department of Medicine, Faculty of Health and Medical Sciences, University of Auckland, New Zealand.
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Brittain JE, Mlinar KJ, Anderson CS, Orringer EP, Parise LV. Activation of sickle red blood cell adhesion via integrin-associated protein/CD47-induced signal transduction. J Clin Invest 2001; 107:1555-62. [PMID: 11413163 PMCID: PMC200189 DOI: 10.1172/jci10817] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Peripheral human red blood cells (RBCs) are not generally known to become activated and adhesive in response to cell signaling. We show, however, that soluble thrombospondin via integrin-associated protein (IAP; CD47) increases the adhesiveness of sickle RBCs (SS RBCs) by activating signal transduction in the SS RBC. This stimulated adhesion requires occupancy of IAP and shear stress and is mediated by the activation of large G proteins and tyrosine kinases. Reticulocyte-enriched RBCs derived from sickle-cell disease (SCD) patients are most responsive to IAP-induced activation. These studies therefore establish peripheral SS RBCs as signaling cells that respond to a novel synergy between IAP-induced signal transduction and shear stress, suggesting new therapeutic targets in SCD.
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Affiliation(s)
- J E Brittain
- Department of Pharmacology, School of Medicine, and. Department of Medicine, The University of North Carolina at Chapel Hill, 27599-7365, USA
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Brittain JE, Mlinar KJ, Anderson CS, Orringer EP, Parise LV. Integrin-associated protein is an adhesion receptor on sickle red blood cells for immobilized thrombospondin. Blood 2001; 97:2159-64. [PMID: 11264185 DOI: 10.1182/blood.v97.7.2159] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The adhesive protein thrombospondin (TSP) potentially mediates sickle (SS) red blood cell (RBC) adhesion to the blood vessel wall, thereby contributing to vaso-occlusive crises in sickle cell disease. We previously reported that SS RBCs bind to immobilized TSP under flow conditions, whereas normal (AA) red cells do not. However, the SS RBC receptors that mediate this interaction are largely unknown. Here it is reported that integrin-associated protein (IAP), or CD47, mediates the adhesion of these cells to immobilized TSP under both flow and static conditions. A peptide derived from the C-terminal IAP binding site of TSP also supports sickle cell adhesion; adhesion to this peptide or to TSP is inhibited specifically by the anti-IAP monoclonal antibody, 1F7. Furthermore, these data suggest that IAP on SS RBCs is structurally different from that expressed on AA RBCs but that IAP expression levels do not vary between AA and SS RBCs. This structural difference may contribute to the enhanced adhesion of SS RBCs to immobilized TSP. These results identify IAP as a TSP receptor on SS RBCs and suggest that this receptor and its binding site within TSP represent potential therapeutic targets to decrease vaso-occlusion. (Blood. 2001;97:2159-2164)
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Affiliation(s)
- J E Brittain
- Department of Pharmacology, School of Medicine, The University of North Carolina at Chapel Hill 27599, USA
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Feigin VL, Anderson CS, Anderson NE, Broad JB, Pledger MJ, Bonita R. Is there a temporal pattern in the occurrence of subarachnoid hemorrhage in the southern hemisphere? Pooled data from 3 large, population-based incidence studies in Australasia, 1981 to 1997. Stroke 2001; 32:613-9. [PMID: 11239176 DOI: 10.1161/01.str.32.3.613] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND PURPOSE Publications on the temporal pattern of the occurrence of subarachnoid hemorrhage (SAH) have produced conflicting results. Variations between studies may relate to the relatively small numbers of SAH cases analyzed, including those in meta-analyses. METHODS We identified all cases of SAH from 3 well-designed population-based studies in Australia (Adelaide, Hobart, and Perth) and New Zealand (Auckland) during 3 periods between 1981 and 1997. The diagnosis of SAH was confirmed with CT, cerebral angiography, cerebrospinal fluid analysis, or autopsy in all cases. Information on the time of occurrence of each event was obtained. Risk ratios (RRs) and 95% CIs were calculated using Poisson regression, with age, sex, smoking status, and history of hypertension entered in the model as covariates. RESULTS A total of 783 cases of SAH were registered. Age- and sex-adjusted RRs of SAH occurrence were highest in the period between 6 AM and 12 MIDNIGHT (RR 3.2, 95% CI 2.4-4.3) and in winter and spring (RR 1.3, 95% CI 1.1-1.5; RR 1.3, 95% CI 1.1-1.5; respectively). No particular pattern of SAH occurrence was observed according to the day of the week. Restriction of the analyses to proved aneurysmal SAH did not substantially change the point estimates. CONCLUSIONS Circadian and circaseptan (weekly) fluctuations of SAH occurrence in the southern hemisphere are similar to those in the northern hemisphere, but the occurrence of SAH in Australasia exhibits clear seasonal (winter and spring) peaks.
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Affiliation(s)
- V L Feigin
- Clinical Trials Research Unit, University of Auckland, Auckland, New Zealand.
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Rubenach S, Anderson CS, Laubscher S. The Short Form-12 by telephone as a measure of health-related quality of life after stroke. Age Ageing 2000; 29:553-4. [PMID: 11191253 DOI: 10.1093/ageing/29.6.553] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Hackett ML, Anderson CS. Health outcomes 1 year after subarachnoid hemorrhage: An international population-based study. The Australian Cooperative Research on Subarachnoid Hemorrhage Study Group. Neurology 2000; 55:658-62. [PMID: 10980729 DOI: 10.1212/wnl.55.5.658] [Citation(s) in RCA: 194] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND There is limited information about the long-term consequences of subarachnoid hemorrhage (SAH). METHODS Data were obtained from a population-based study of aneurysmal SAH conducted in Australia and New Zealand between 1995 and 1998. The authors report health outcomes for survivors 1 year after the onset of SAH. RESULTS From a total of 432 first-ever cases of SAH (76% due to confirmed cerebral aneurysm rupture) registered in four cities in Australia and New Zealand, 242 (56%) were alive approximately 1 year later (mean time 1.2 years), with 230 (95%) available for interview. Of those interviewed, 105 (46%) reported an incomplete recovery, with ongoing problems with memory (50%), mood (39%), speech (14%), and self-care (10%). Compared with age- and sex-adjusted Australian population norms, health-related quality of life, as determined by Short Form-36, was significantly lower for cases in the domains of role limitations that result from physical problems. However, there were no patient or disease characteristics that predicted complete recovery from SAH. CONCLUSIONS A high proportion of long-term survivors of SAH experience ongoing deficits in high level (neuropsychological) functioning. These deficits result in impairment in social roles.
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Affiliation(s)
- M L Hackett
- Clinical Trials Research Unit, The University of Auckland, New Zealand.
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Hankey GJ, Jamrozik K, Broadhurst RJ, Forbes S, Burvill PW, Anderson CS, Stewart-Wynne EG. Five-year survival after first-ever stroke and related prognostic factors in the Perth Community Stroke Study. Stroke 2000; 31:2080-6. [PMID: 10978033 DOI: 10.1161/01.str.31.9.2080] [Citation(s) in RCA: 258] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Few community-based studies have examined the long-term survival and prognostic factors for death within 5 years after an acute first-ever stroke. This study aimed to determine the absolute and relative survival and the independent baseline prognostic factors for death over the next 5 years among all individuals and among 30-day survivors after a first-ever stroke in a population of Perth, Western Australia. METHODS Between February 1989 and August 1990, all individuals with a suspected acute stroke or transient ischemic attack of the brain who were resident in a geographically defined region of Perth, Western Australia, with a population of 138 708 people, were registered prospectively and assessed according to standardized diagnostic criteria. Patients were followed up prospectively at 4 months, 12 months, and 5 years after the index event. RESULTS Three hundred seventy patients with first-ever stroke were registered, and 362 (98%) were followed up at 5 years, by which time 210 (58%) had died. In the first year after stroke the risk of death was 36.5% (95% CI, 31.5% to 41.4%), which was 10-fold (95% CI, 8.3% to 11.7%) higher than that expected among the general population of the same age and sex. The most common cause of death was the index stroke (64%). Between 1 and 5 years after stroke, the annual risk of death was approximately 10% per year, which was approximately 2-fold greater than expected, and the most common cause of death was cardiovascular disease (41%). The independent baseline factors among 30-day survivors that predicted death over 5 years were intermittent claudication (hazard ratio [HR], 1.9; 95% CI, 1.2 to 2.9), urinary incontinence (HR, 2.0; 95% CI, 1. 3 to 3.0), previous transient ischemic attack (HR, 2.4; 95% CI, 1.4 to 4.1), and prestroke Barthel Index <20/20 (HR, 2.0; 95% CI, 1.2 to 3.2). CONCLUSIONS One-year survivors of first-ever stroke continue to die over the next 4 years at a rate of approximately 10% per year, which is twice the rate expected among the general population of the same age and sex. The most common cause of death is cardiovascular disease. Long-term survival after stroke may be improved by early, active, and sustained implementation of effective strategies for preventing subsequent cardiovascular events.
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Affiliation(s)
- G J Hankey
- Stroke Unit, Department of Neurology, Royal Perth Hospital (Western Australia).
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Abstract
BACKGROUND AND PURPOSE The goal of the present study was to identify risk factors for vascular disease in the elderly. METHODS We conducted a prospective study of control subjects from a population-based study of stroke in Perth, Western Australia, that was completed in 1989 to 1990 and used record linkage and a survey of survivors to identify deaths and nonfatal vascular events. Data validated through reference to medical records were analyzed with the use of Cox proportional hazards models. RESULTS Follow-up for the 931 subjects was 88% complete. By June 24, 1994, 198 (24%) of the subjects had died (96 from vascular disease), and there had been 45 nonfatal strokes or myocardial infarctions. The hazard ratio for diabetes exceeded 2.0 for all end points, whereas the consumption of meat >4 times weekly was associated with a reduction in risk of </=30%. In most models, female sex and consumption of alcohol were associated with reduced risks, whereas previous myocardial infarction was linked to an increase in risk. CONCLUSIONS There are only limited associations between lifestyle and major vascular illness in old age. Effective health promotion activities in early and middle life may be the key to a longer and healthier old age.
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Affiliation(s)
- K Jamrozik
- Department of Public Health, Royal Perth Hospital, University of Western Australia, Perth, Australia
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Hackett ML, Duncan JR, Anderson CS, Broad JB, Bonita R. Health-related quality of life among long-term survivors of stroke : results from the Auckland Stroke Study, 1991-1992. Stroke 2000; 31:440-7. [PMID: 10657420 DOI: 10.1161/01.str.31.2.440] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE The consequences of stroke are a major health concern. This study was conducted to compare the health-related quality of life among long-term survivors of stroke with that of the general population. METHODS Our data are taken from a population-based case-control study of all 6-year survivors of stroke with an age- and sex-matched control population. SF-36 mean scores for cases were compared with raw and standardized control and New Zealand norm mean scores. RESULTS Of the original 1761 registered cases, 639 were still alive at 6-year follow-up, and all of these participated in the study. Case patients were more likely than control subjects to be dependent in all basic activities of daily living. Crude mean scores were lower for women; as age increased; for those living in institutions; when the SF-36 was completed by proxy; and when help was required with the activities of daily living. Cases had statistically lower mean scores than both the control group and New Zealand norms for physical functioning and general health. After standardization for age and sex, no differences were found between cases and controls in mental health and bodily pain. CONCLUSIONS Health-related quality of life appears to be relatively good for the majority of patients 6 years after stroke. Despite significant ongoing physical disability, survivors of stroke appear to adjust well psychologically to their illness.
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Affiliation(s)
- M L Hackett
- Clinical Trials Research Unit, Department of Medicine, The University of Auckland, New Zealand.
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Jamrozik K, Broadhurst RJ, Lai N, Hankey GJ, Burvill PW, Anderson CS. Trends in the incidence, severity, and short-term outcome of stroke in perth, Western Australia. Stroke 1999; 30:2105-11. [PMID: 10512914 DOI: 10.1161/01.str.30.10.2105] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE This report describes trends in the key indices of cerebrovascular disease over 6 years from the end of the 1980s in a geographically defined segment of the city of Perth, Western Australia. METHODS Identical methods were used to find and assess all cases of suspected stroke in a population of approximately 134 000 residents in a triangular area of the northern suburbs of Perth. Case fatality was measured as vital status at 28 days after the onset of symptoms. Data for first-ever strokes and for all strokes for equivalent periods of 12 months in 1989-1990 and 1995-1996 were compared by age-standardized rates and proportions and Poisson regression. RESULTS There were 355 strokes in 328 patients and 251 first-ever strokes (71%) for 1989-1990 and 290 events in 281 patients and 213 first-ever strokes (73%) for 1995-1996. In Poisson models including age and period, overall trends in the incidence of both first-ever strokes (rate ratio=0.75; 95% confidence limits, 0.63, 0.90) and all strokes (rate ratio=0.73; 95% confidence limits, 0.62, 0.85) were obviously significant, but only the changes in men were independently significant. Case fatality did not change, and the balance between hemorrhagic and occlusive strokes in 1995-1996 was almost indistinguishable from that observed in 1989-1990. CONCLUSIONS Our results, which are the only longitudinal population-based data available for Australia for key indices of stroke, suggest that it is a change in the frequency of stroke, rather than its outcome, that is chiefly responsible nationally for the fall in mortality from cerebrovascular disease.
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Affiliation(s)
- K Jamrozik
- University of Western Australia, Nedlands, Western Australia
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Hankey GJ, Jamrozik K, Broadhurst RJ, Forbes S, Burvill PW, Anderson CS, Stewart-Wynne EG. Long-term risk of first recurrent stroke in the Perth Community Stroke Study. Stroke 1998; 29:2491-500. [PMID: 9836757 DOI: 10.1161/01.str.29.12.2491] [Citation(s) in RCA: 210] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
BACKGROUND AND PURPOSE Few community-based studies have examined the long-term risk of recurrent stroke after an acute first-ever stroke. This study aimed to determine the absolute and relative risks of a first recurrent stroke over the first 5 years after a first-ever stroke and the predictors of such recurrence in a population-based series of people with first-ever stroke in Perth, Western Australia. METHODS Between February 1989 and August 1990, all people with a suspected acute stroke or transient ischemic attack of the brain who were resident in a geographically defined region of Perth, Western Australia, with a population of 138 708 people, were registered prospectively and assessed according to standardized diagnostic criteria. Patients were followed up prospectively at 4 months, 12 months, and 5 years after the index event. RESULTS Three hundred seventy patients with a first-ever stroke were registered, of whom 351 survived >2 days. Data were available for 98% of the cohort at 5 years, by which time 199 patients (58%) had died and 52 (15%) had experienced a recurrent stroke, 12 (23%) of which were fatal within 28 days. The 5-year cumulative risk of first recurrent stroke was 22.5% (95% confidence limits [CL], 16.8%, 28.1%). The risk of recurrent stroke was greatest in the first 6 months after stroke, at 8.8% (95% CL, 5.4%, 12.1%). After adjustment for age and sex, the prognostic factors for recurrent stroke were advanced, but not extreme, age (75 to 84 years) (hazard ratio [HR], 2.6; 95% CL, 1.1, 6.2), hemorrhagic index stroke (HR, 2.1; 95% CL, 0.98, 4.4), and diabetes mellitus (HR, 2.1; 95% CL, 0.95, 4.4). CONCLUSIONS Approximately 1 in 6 survivors (15%) of a first-ever stroke experience a recurrent stroke over the next 5 years, of which 25% are fatal within 28 days. The pathological subtype of the recurrent stroke is the same as that of the index stroke in 88% of cases. The predictors of first recurrent stroke in this study were advanced age, hemorrhagic index stroke, and diabetes mellitus, but numbers of recurrent events were modest. Because the risk of recurrent stroke is highest (8.8%) in the first 6 months after stroke, strategies for secondary prevention should be initiated as soon as possible after the index event.
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Affiliation(s)
- G J Hankey
- Stroke Unit, Department of Neurology, Royal Perth Hospital, Perth, Western Australia.
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Anderson CS, Zari MC, Ward RN. Radiometers, autocorrelators, and matched-filter receivers by means of acousto-optic spectrum analysis. Appl Opt 1997; 36:1064-1072. [PMID: 18250774 DOI: 10.1364/ao.36.001064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Acousto-optic spectrum analyzers provide a convenient means of separating wide-bandwidth signals into their frequency components. By a change in the rf input signal into the spectrum analyzer and by the provision of additional digital postprocessing, it is possible to perform radiometry, signal autocorrelation, and matched-filter reception. Although the acousto-optic device has a space-integrating architecture, the matched-filter receiver can be implemented for signals having time durations much longer than the acousto-optic cell. The resulting signal-to-noise ratio improvements from the receiver are consistent with the time-bandwidth product of the waveform, rather than the time-bandwidth product of the acousto-optic device. A mathematical foundation of the processor is presented along with specific receiver implementations. Computer-simulation and experimental results demonstrate key findings. In one experimental example, a linear-frequency-modulated waveform is matched-filter processed to recover a signal that is -24 dB with respect to the input noise floor.
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Anderson CS. Contribution of prevention to vascular cerebral disease management. J Hypertens Suppl 1996; 14:S25-8. [PMID: 9023712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Epidemiological studies suggest that significant reductions in the incidence of stroke, as with coronary heart disease, can be expected by reducing the prevalence or shifting the distribution of risk factors across the entire population. Thus, identifying risk factors and intervening to control or modify them remains the most important means of further reducing the incidence and case fatality of stroke in developed countries, and controlling the emerging epidemic of cardiovascular disease in developing countries. All people should be encouraged to stop smoking, reduce weight, and increase physical activity and the consumption of fruit and vegetables. METHODS The high-risk strategy involves the identification and management of people at high risk of developing stroke. Therapies of proven benefit in the prevention of stroke among certain individuals are blood pressure lowering therapy, antiplatelet therapy, anticoagulation therapy and carotid endarterectomy. Evidence is mounting that aggressive treatment of hypercholestrolaemia and hyperglycaemia is also effective in reducing the risk of stroke, but the role of aspirin and carotid endarterectomy in the primary prevention of stroke remains uncertain. This article will review strategies for the prevention of stroke, except blood pressure lowering therapy, which is discussed elsewhere, and address some of the questions about which individuals have the most to gain from various interventions.
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Affiliation(s)
- C S Anderson
- Department of Medicine, Flinders Medical Centre, Bedford Park, Australia
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Anderson CS. Fringe visibility, irradiance, and accuracy in common path interferometers for visualization of phase disturbances. Appl Opt 1995; 34:7474-85. [PMID: 21060622 DOI: 10.1364/ao.34.007474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Common-path interferometers have been used to perform phase visualization for over 40 years. A number of techniques have been proposed, including dark central ground, phase contrast (π/2 and π), and field-absorption interferometers. The merits of the interferometers have been judged ad hoc by either tests with a small number of phase objects or by computer simulation. Three standardized criteria, which consolidate the work of others, are proposed to evaluate common-path interferometers: fringe visibility, fringe irradiance, and fringe accuracy. The interferometers can be described as one generic class of Fourier-plane filters and can be analyzed for all input conditions. Closed-form expressions are obtained for visibility and irradiance under the forced condition that little inaccuracy is tolerated. This analysis finds that the π-phase-contrast interferometer is a good choice if the optical phase disturbance is at least 2π; for smaller disturbances, the Π/2 filter selected by Zernike is near optimum. It is shown mathematically that the resulting fringe visibility is highly object dependent, and good results are not ensured. By allowing the optical beam to be 50% larger than the phase object, the interferometer performs well under all conditions. With this approach and a combination π-phase/field-absorption filter, interference fringe visibility is greater than 0.8 for all phase objects.
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Abstract
BACKGROUND AND PURPOSE Little attention has been focused on the demands on caregivers in stroke outcome research. A major aim of this study was to identify factors in patients associated with emotional distress in caregivers 1 year after stroke. METHODS One-year stroke survivors with residual handicap (defined by the Oxford Handicap Scale) and their chief caregivers were interviewed as part of the follow-up activities for patients (n = 492) registered with the Perth Community Stroke Study. We assessed emotional distress in caregivers using the Hospital Anxiety and Depression Scale and the 28-item General Health Questionnaire. Appropriate sections of the Social Behaviour Assessment Schedule were used to assess the patient's behavior and the impact on the caregiver's life. Other aspects of the patient's functional state were assessed with the Barthel Index, the Mini-Mental State Examination, the Frenchay Activities Index, and the Psychiatric Assessment Schedule (at 4 months after stroke). RESULTS Of 241 patients who survived to 1 year after stroke and were living outside of an institution, 103 patients (43%; 95% confidence interval, 37% to 49%) were handicapped. Eighty-four patient/caregiver units were assessed from this latter group. Almost all caregivers reported adverse effects on their emotional health, social activities, and leisure time, and more than half reported adverse effects on family relationships. Forty-six caregivers (55%) showed evidence of emotional distress on either of the two screening instruments, particularly if they were caregiving for patients with dementia and/or abnormal behavior. There was no significant relationship between emotional illness among caregivers and the degree of patients' physical disability. CONCLUSIONS In this population, the high level of emotional distress among caregivers of stroke patients suggests that many caregivers have unmet needs. Community services need to focus attention on the neuropsychological aspects of stroke patients and the social functioning of caregivers who support them.
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Affiliation(s)
- C S Anderson
- Department of Medicine (Rehabilitation and Ageing Studies Unit), Flinders University of South Australia, Repatriation General Hospital, Daw Park
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Johnson G, Burvill PW, Anderson CS, Jamrozik K, Stewart-Wynne EG, Chakera TM. Screening instruments for depression and anxiety following stroke: experience in the Perth community stroke study. Acta Psychiatr Scand 1995; 91:252-7. [PMID: 7625207 DOI: 10.1111/j.1600-0447.1995.tb09778.x] [Citation(s) in RCA: 108] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Evaluation of the relative efficacy of three screening instruments for depression and anxiety in a group of stroke patients was undertaken as part of the Perth community stroke study. Data are presented on the sensitivity and specificity of the Hospital Anxiety and Depression Scale (HAPS), the Geriatric Depression Scale and the General Health Questionnaire (GHQ) (28-item version) in screening patients 4 months after stroke for depressive and anxiety disorders diagnosed according to DSM-III criteria. The GHQ-28 and GDS but not the HADS depression, were shown to be satisfactory screening instruments for depression, with the GHQ-28 having an overall superiority. The performance of all 3 scales for screening post-stroke anxiety disorders was less satisfactory. The HADS anxiety had the best level of sensitivity, but the specificity and positive predictive values were low and the misclassification rate high.
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Affiliation(s)
- G Johnson
- Department of Psychiatry & Behavioural Science, University of Western Australia, Nedlands
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Abstract
BACKGROUND The Perth Community Stroke Study (PCSS) was a population-based study of the incidence, cause, and outcome of acute stroke. METHOD Subjects from the study were assessed initially, by examination and interview, and at four- and 12-month follow-ups to determine differences in prevalence of depression between the sexes and between patients with first-ever and recurrent strokes. RESULTS The prevalence of depressive illness four months after stroke in 294 patients from the PCSS was 23% (18-28%), 15% (11-19%) major depression and 8% (5-11%) minor depression. There were no significant differences between the sexes or between patients with first-ever and recurrent strokes. With a non-hierarchic approach to diagnosis of those with depression, 26% of men and 39% of women had an associated anxiety disorder, mainly agoraphobia. Nine per cent of male and 13% of female patients interviewed had evidence of depression at the time of the stroke. Twelve months after stroke 56% of the men were still depressed (40% major and 16% minor), as were 30% of the women (12% major and 18% minor). CONCLUSION The prevalence of depression after stroke was comparable with that reported from other studies, and considerably less than that reported from in-patient and rehabilitation units.
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Affiliation(s)
- P W Burvill
- Department of Psychiatry and Behavioural Science, University of Western Australia, Perth
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Burvill PW, Johnson GA, Jamrozik KD, Anderson CS, Stewart-Wynne EG, Chakera TM. Anxiety disorders after stroke: results from the Perth Community Stroke Study. Br J Psychiatry 1995; 166:328-32. [PMID: 7788124 DOI: 10.1192/bjp.166.3.328] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND The prevalence of anxiety disorders in 294 patients who survived to four months in the Perth Community Stroke Study (Perth, Australia), and a follow-up of these patients at 12 months, are presented. METHOD Diagnoses are described both in the usual DSM hierarchic format and by a non-hierarchic approach. Adoption of the hierarchic approach alone greatly underestimates the prevalence of anxiety disorders. RESULTS Most cases were of agoraphobia, and the remainder were generalised anxiety disorder. The prevalence of anxiety disorders alone was 5% in men and 19% in women; in community controls, it was 5% in men and 8% in women. Adopting a non-hierarchic approach to diagnosis gave a prevalence of 12% in men and 28% in women. When those who showed evidence of anxiety disorder before stroke were subtracted, the latter prevalence was 9% in men and 20% in women. CONCLUSION One-third of the men and half of the women with post-stroke anxiety disorders showed evidence of either depression or an anxiety disorder at the time of the stroke. At 12 month follow-up of 49 patients with agoraphobia by a non-hierarchic approach, 51% had recovered, and equal proportions of the remainder had died or still had agoraphobia. The only major difference in outcome between those with anxiety disorder alone and those with comorbid depression was the greater mortality in the latter.
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Affiliation(s)
- P W Burvill
- Department of Psychiatry and Behavioural Science, University of Western Australia, Perth
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Anderson CS, Jamrozik KD, Broadhurst RJ, Stewart-Wynne EG. Predicting survival for 1 year among different subtypes of stroke. Results from the Perth Community Stroke Study. Stroke 1994; 25:1935-44. [PMID: 8091436 DOI: 10.1161/01.str.25.10.1935] [Citation(s) in RCA: 130] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND AND PURPOSE Few studies have evaluated the factors influencing or predicting long-term survival after stroke in an unselected series of patients in whom the underlying cerebrovascular pathology is clearly defined. Moreover, the relative importance of risk factors for stroke, including sociodemographic and premorbid variables, has not been described in detail. METHODS The study cohort consisted of 492 patients with stroke who were registered with a population-based study of acute cerebrovascular disease undertaken in Perth, Western Australia, during an 18-month period in 1989 and 1990. Objective evidence of the pathological basis of the stroke was obtained in 86% of cases, and all deaths among patients during a follow-up of 1 year were reviewed. RESULTS One hundred twenty patients (24%) died within 28 days of the onset of stroke. Among the different subtypes of stroke, the 1-year case fatality (mean, 38%) varied from 6% and 16% for boundary zone infarction and lacunar infarction, respectively, to 42% and 46% for subarachnoid hemorrhage and primary intracerebral hemorrhage, respectively. Using Cox proportional-hazards analysis, a predictive model was developed on 321 patients with acute stroke (test sample). The best model contained five baseline variables that were independent predictors of death within 1 year: coma (relative risk [RR], 3.0; 95% confidence interval [CI], 1.1 to 8.4), urinary incontinence (RR, 3.9; 95% CI, 1.4 to 10.6), cardiac failure (RR, 6.5; 95% CI, 2.8 to 15.1), severe paresis (RR, 4.9; 95% CI, 1.6 to 15.5), and atrial fibrillation (RR, 2.0; 95% CI, 1.1 to 3.5). The sensitivity, specificity, and negative predictive value of this model for predicting death were 90%, 83%, and 95%, respectively. When applied to a second randomly selected validation sample of 171 events, sensitivity was 94%, specificity 62%, and negative predictive value 92%, indicating stability of the model. CONCLUSIONS Although the case fatality, timing, and cause of death vary considerably among the different pathological subtypes of stroke, simple clinical measures that reflect the severity of the neurological deficit and associated cardiac disease at onset independently predict death by 1 year and may help to direct management.
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Affiliation(s)
- C S Anderson
- Department of Medicine, Flinders University of South Australia, Bedford Park
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Anderson CS, Taylor BV, Hankey GJ, Stewart-Wynne EG, Jamrozik KD. Validation of a clinical classification for subtypes of acute cerebral infarction. J Neurol Neurosurg Psychiatry 1994; 57:1173-9. [PMID: 7931376 PMCID: PMC485481 DOI: 10.1136/jnnp.57.10.1173] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The validity of a clinical classification system was assessed for subtypes of cerebral infarction for use in clinical trials of putative stroke therapies and clinical decision making in a population based stroke register (n = 536) compiled in Perth, Western Australia in 1989-90. The Perth Community Stroke Project (PCSS) used definitions and methodology similar to the Oxfordshire Community Stroke Project (OCSP) where the classification system was developed. In the PCSS, 421 cases of cerebral infarction and primary intracerebral haemorrhage (PICH), confirmed by brain imaging or necropsy, were classified into the subtypes total anterior circulation syndrome (TACS), partial anterior circulation syndrome (PACS), lacunar syndrome (LACS), and posterior circulation syndrome (POCS). In this relatively unselected population, relying exclusively on LACS for a diagnosis of PICH had a very low sensitivity (6%) and positive predictive value (3%). Comparison of the frequencies and outcomes (at one year after the onset of symptoms) for each subgroup of first ever cerebral infarction in the PCSS (n = 248) with the OCSP (n = 543) registers showed uniformity only for LACI. For example, there were 27% of cases of TACI in the PCSS compared with 17% in the OCSP (difference = 10%; 95% confidence interval (95% CI) 4% to 16%) and 15% of cases in the PCSS compared with 24% in the OCSP were POCI (difference = 9%; 95% CI 3% to 15%). Case fatalities and long-term handicap across the subgroups were not significantly different between studies, but the frequencies of recurrent stroke were significantly greater for POCI in the OCSP compared with the PCSS. Although this classification system defines subtypes of stroke with different outcomes, simple clinical measures-level of consciousness, paresis, disability, and incontinence at onset-are more powerful predictors of death or dependency at one year. It is concluded that simple clinical measures that reflect the severity of the neurological deficit should complement this classification system in clinical trials and practice.
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Affiliation(s)
- C S Anderson
- Department of Medicine, Flinders University of South Australia, Bedford Park
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Anderson CS, Chakera TM, Stewart-Wynne EG, Jamrozik KD. Spectrum of primary intracerebral haemorrhage in Perth, Western Australia, 1989-90: incidence and outcome. J Neurol Neurosurg Psychiatry 1994; 57:936-40. [PMID: 8057117 PMCID: PMC1073077 DOI: 10.1136/jnnp.57.8.936] [Citation(s) in RCA: 136] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In a population based register of stroke (n = 536) compiled in Perth, Western Australia during an 18 month period in 1989-90, 60 cases (11%) of primary intracerebral haemorrhage were identified among 56 persons (52% men). The mean age of these patients was 68 (range 23-93) and 46 (77%) events were first ever strokes. The crude annual incidence was 35 per 100,000, with a peak in the eighth decade, and a male predominance. Deep and lobar haemorrhages each accounted for almost one third of all cases. The clinical presentations included sudden coma (12%), headache (8%), seizures (8%), and pure sensory-motor stroke (3%). Primary intracerebral haemorrhage was the first presentation of leukaemia in two cases (both fatal) and it followed an alcoholic binge in four cases. 55% had a history of hypertension. 16 (27%) patients, half of whom had a history of hypertension, were taking antiplatelet agents, and one patient was taking warfarin. There were only two confirmed cases of amyloid angiopathy. The overall 28 day case fatality was 35%, but this varied from 100% for haemorrhages in the brainstem to 22% for those in the basal ganglionic or thalamic region. Other predictors of early death were intraventricular extension of blood, volume of haematoma, mass effect, and coma and severe paresis at onset. Although based on small numbers, these data confirm the heterogeneous nature of primary intracerebral haemorrhage, but they also suggest a different clinical spectrum of this type of stroke in the community compared with the experience of specialist neurological units.
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Affiliation(s)
- C S Anderson
- Department of Medicine, Flinders Medical Centre, Bedford Park, South Australia
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Bonita R, Anderson CS, Broad JB, Jamrozik KD, Stewart-Wynne EG, Anderson NE. Stroke incidence and case fatality in Australasia. A comparison of the Auckland and Perth population-based stroke registers. Stroke 1994; 25:552-7. [PMID: 8128506 DOI: 10.1161/01.str.25.3.552] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND AND PURPOSE Population-based studies are crucial for identifying explanations for the decline in mortality from stroke and for generating strategies for public health policy. However, the present particular methodological difficulties, and comparability between them is generally poor. In this article we compare the incidence and case fatality of stroke as assessed by two independent well-designed incidence studies. METHODS Two registers of acute cerebrovascular events were compiled in the geographically defined metropolitan areas of Auckland, New Zealand (population 945,369), during 1991-1992 for 12 months and Perth, Australia (population 138,708), during 1989-1990 for 18 months. The protocols for each register included prospective ascertainment of cases using multiple overlapping sources and the application of standardized definitions and criteria for stroke and case fatality. RESULTS In Auckland, 1803 events occurred in 1761 residents, 73% of which were first-ever strokes. The corresponding figures for Perth were 536 events in 492 residents, 69% of which were first-ever strokes. Both studies identified a substantial proportion of nonfatal strokes managed solely outside the hospital system: 28% in Auckland and 22% in Perth of all patients registered. The age-standardized annual incidence of stroke (all events) was 27% higher among men in Perth compared with Auckland (odds ratio, 1.27; P = .016); women tended to have higher rates in Auckland, although these differences were not statistically significant. In both centers approximately a quarter of all patients died within the first month after a stroke. There were significant differences in the prevalence of hypertension among first-ever strokes. CONCLUSIONS These two studies emphasize the importance of identifying all patients with stroke, both hospitalized and nonhospitalized, in order to measure the incidence of stroke accurately. The incidence and case fatality of stroke were remarkably similar in Auckland and Perth in the early 1990s. However, there are differences in the sex-specific rates that correspond to differences in the pattern of risk factors.
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Affiliation(s)
- R Bonita
- Section of Geriatric Medicine, University of Auckland, New Zealand
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Jamrozik K, Broadhurst RJ, Anderson CS, Stewart-Wynne EG. The role of lifestyle factors in the etiology of stroke. A population-based case-control study in Perth, Western Australia. Stroke 1994; 25:51-9. [PMID: 8266383 DOI: 10.1161/01.str.25.1.51] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND AND PURPOSE We sought to examine risk factors for all strokes and for ischemic stroke and primary intracerebral hemorrhage separately. METHODS This was a population-based case-control study. Each case subject meeting World Health Organization criteria for stroke (n = 536) from a population-based register of acute cerebrovascular events compiled in Perth, Western Australia, in 1989 to 1990 was matched for age and sex with up to five control subjects drawn from the same geographical area. Objective confirmation of the type of stroke was available from computed tomography, magnetic resonance imaging, or necropsy for 86% of the case subjects. Data on medical history and lifestyle factors were collected from case and control subjects by interview of the subject or a proxy informant. RESULTS Current smoking, consumption of meat more than four times weekly, and a history of hypertension or intermittent claudication were each associated with increased risk in multivariate models for all strokes and for all first-ever strokes. Consumption of 1 to 20 g/d alcohol in the preceding week was associated with a significant reduction in the risk of all strokes, all ischemic strokes, and of primary intracerebral hemorrhage, while eating fish more than two times per month appeared to protect against first-ever stroke and against primary intracerebral hemorrhage. Diabetes mellitus was associated with a significantly increased risk of ischemic stroke but a decreased risk of hemorrhagic stroke. CONCLUSIONS Risk factors for ischemic and hemorrhagic stroke are not exactly the same. Changes in lifestyle relating to tobacco and diet might make important contributions to further reductions in the incidence of stroke.
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Affiliation(s)
- K Jamrozik
- Department of Public Health, University of Western Australia, Perth
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Anderson CS. Acousto-optic channel equalization for microwave digital radios. Appl Opt 1993; 32:4388-4397. [PMID: 20830097 DOI: 10.1364/ao.32.004388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Digital radio transmission systems use complex modulation schemes that require powerful signalprocessing techniques to correct channel distortions and to minimize bit error rates. Acousto-optic processors are used, in conjunction with adaptive digital equalizers, to reduce the bit error rate of the digital radio receiver. The acousto-optic processor implements an inverse channel filter that is rapidly adaptable to time-varying distortions. A specific architecture is identified and a laboratory system is tested to verify the ability of the processor to track and correct time-varying channels. Computer simulations are used to show that the hybrid acousto-optic and digital equalizer permits a fourfold increase in the modulation capacity of radio, relative to all digital equalization, while improving the bit error rate performance.
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Vanderlugt A, Anderson CS, Melsa PJ. Time-delay detection of short pulses by Fresnel and Fourier transformations. Appl Opt 1993; 32:3761-3771. [PMID: 20830005 DOI: 10.1364/ao.32.003761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The Fresnel transform of a signal, when used as a preprocessing step to a subsequent spectrum analysis, helps to detect the time delay between short-pulse signals. Light from the short pulses disperses spatially as it propagates through free space to create an interference pattern. As the pulses move through an acousto-optic cell, a point photodetector produces a signal whose temporal frequency is directly proportional to the time delay between the pulses. When this signal is fed to a spectrum analyzer, the frequency domain represents a time-delay domain.
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Anderson CS, Jamrozik KD, Burvill PW, Chakera TM, Johnson GA, Stewart-Wynne EG. Determining the incidence of different subtypes of stroke: results from the Perth Community Stroke Study, 1989-1990. Med J Aust 1993; 158:85-9. [PMID: 8419781 DOI: 10.5694/j.1326-5377.1993.tb137529.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To determine the incidence and case fatality of seven distinct subtypes of stroke in Perth, Western Australia. DESIGN AND SETTING A population-based descriptive epidemiological study. SUBJECTS All residents of a geographically defined segment of the Perth metropolitan area (estimated population 138,708 persons) who had a stroke or transient ischaemic attack between 20 February 1989 and 19 August 1990, inclusive. MAIN OUTCOME MEASURES The following subtypes of stroke were classified according to standard clinical, radiological and pathological criteria: types of cerebral infarction, namely, large artery (thrombotic) occlusive infarction (LAOI), cerebral embolic infarction (EMBI), lacunar infarction (LACI) and boundary zone infarction (BZI); primary intracerebral haemorrhage (PICH); subarachnoid haemorrhage (SAH); and stroke of undetermined cause. RESULTS Over the 18-month study period 536 stroke events were registered, of which 86% (95% confidence interval, 83%-89%) had a defined "pathological" diagnosis on the basis of computed tomographic scanning, magnetic resonance imaging or necropsy. Cerebral infarction accounted for 71% of cases (95% CI, 68%-75%), PICH 11% (95% CI, 9%-14%) and SAH 4% (95% CI, 2%-5%). The 382 cases of cerebral infarction included LAOI (in approximately 71%), EMBI (15%), LACI (10%) and BZI (5%). While the incidence of all subtypes of stroke increased with age, there were age and sex differences in their proportional frequency, management and prognosis: patients with PICH, SAH and EMBI were more likely to be admitted to hospital, and these conditions carried the highest early case fatality. Over all, the 28-day case fatality was 24% (95% CI, 20%-28%), but varied from 0 for LACI and BZI, to 37% (95% CI, 15%-59%) for SAH and 35% (CI, 23%-47%) for PICH. CONCLUSIONS In this study, we found considerable differences in incidence rates, the effect of age and sex on incidence rates, and prognosis for the different subtypes of stroke. Hospital-based studies are likely to be selectively biased by emphasising strokes that are severe and require admission to hospital. These data have important implications in the design and evaluation of clinical trials of therapy for stroke.
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Affiliation(s)
- C S Anderson
- Department of Neurology, Royal Perth Hospital, WA
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Anderson CS, Jamrozik KD, Burvill PW, Chakera TM, Johnson GA, Stewart-Wynne EG. Ascertaining the true incidence of stroke: experience from the Perth Community Stroke Study, 1989-1990. Med J Aust 1993; 158:80-4. [PMID: 8419780 DOI: 10.5694/j.1326-5377.1993.tb137528.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To determine the age and sex specific incidence, and case fatality of stroke in Perth, Western Australia. DESIGN AND SETTING A population-based descriptive epidemiological study. SUBJECTS All residents of a geographically defined segment of the Perth metropolitan area (population 138,708) who had a stroke or transient ischaemic attack between 20 February 1989 and 19 August 1990, inclusive. MAIN OUTCOME MEASURES Definite acute "first-ever-in-a-lifetime" (first-ever) and recurrent stroke classified according to standard definitions and criteria. RESULTS During the 18-month study period, 536 stroke events occurred among 492 patients, 69% of which were first-ever strokes. The crude annual event rate for all strokes was 258 (95% confidence interval 231-285) per 100,000, and the overall case fatality at 28 days was 24% (95% CI, 20%-28%). The crude annual incidence for first-ever strokes was 178 (95% CI, 156-200) per 100,000; 189 (95% CI, 157-221) per 100,000 in males and 166 (95% CI, 136-196) per 100,000 in females. The corresponding rates, age-adjusted to the "world" population, were 132 (95% CI, 109-155) for males and 77 (95% CI, 60-94) for females. CONCLUSIONS In contrast to mortality rates for ischaemic heart disease, the incidence of stroke in Australia appears little different from that for several other Western countries. For both males and females the incidence of stroke rises exponentially with increasing age. Although the sex-dependent difference in the risk of stroke is greatest in middle age, males are at greater risk of stroke even among the most elderly. To determine the incidence of stroke accurately, population-based studies of stroke need exhaustive and overlapping sources of case ascertainment. If only cases admitted to hospital had been used, we would have underestimated the rate of stroke among the most elderly by almost 40%. We estimate that approximately 37,000 people, about 50% of whom are over the age of 75, suffer a stroke each year in Australia.
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Affiliation(s)
- C S Anderson
- Department of Neurology, Royal Perth Hospital, WA
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Anderson CS, Jamrozik KD, Stewart-Wynne EG. Predicting survival after stroke: experience from the Perth Community Stroke Study. Clin Exp Neurol 1992; 29:117-28. [PMID: 1343856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
Survival is the most fundamental measure of the outcome from stroke, the magnitude of the burden being strongly reflected in case-fatality and survival rates. Although the literature is rich with follow-up studies examining survival after stroke, most are based on selected series of patients and factors which correlated with time to death have usually been determined in univariate analyses. We examined the factors associated with a high risk of death during the acute phase of stroke. Analyses were based on data from a population based study of acute cerebrovascular disease undertaken in Perth, Western Australia, during an 18 month period 1989-1990. Using logistic regression modelling techniques only 2 factors, severe loss of consciousness, odds ratio 14.7 [95% confidence limits (CL), 4.0-53.6], and severe paresis, odds ratio 7.2 [95% CL, 1.6-32.0], independently predicted death by 28 days after the onset of stroke. The implication is that 2 simple measures, level of consciousness and motor power, may help direct management. Furthermore, age is not an independent risk factor for death early after stroke. Therefore the elderly should not be denied therapy purely on the basis of their age.
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Affiliation(s)
- C S Anderson
- Department of Medicine (Neurology), Flinders Medical Centre, Bedford Park, South Australia
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Anderson KC, Goodnough LT, Sayers M, Pisciotto PT, Kurtz SR, Lane TA, Anderson CS, Silberstein LE. Variation in blood component irradiation practice: implications for prevention of transfusion-associated graft-versus-host disease. Blood 1991; 77:2096-102. [PMID: 2029574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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Anderson CS, Vanderlugt A. Hybrid acousto-optic and digital equalization for microwave digital radio channels. Opt Lett 1990; 15:1182-1184. [PMID: 19771034 DOI: 10.1364/ol.15.001182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Digital radio transmission systems use complex modulation schemes that require powerful signal-processing techniques to correct channel distortions and to minimize bit error rates. We propose combining the computation power of acousto-optic processing and the accuracy of digital processing to produce a hybrid channel equalizer that exceeds the performance of digital equalization alone. Analysis shows that a hybrid equalizer for 256-level quadrature amplitude modulation (QAM) performs better than a digital equalizer for 64-level QAM.
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Donnelly KC, Thomas JC, Anderson CS, Brown KW. The influence of application rate on the bacterial mutagenicity of soil amended with municipal sewage sludge. Environ Pollut 1990; 68:147-159. [PMID: 15092199 DOI: 10.1016/0269-7491(90)90018-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/1989] [Accepted: 07/10/1990] [Indexed: 05/24/2023]
Abstract
The mutagenic potential of two soils amended with a municipal sewage sludge at two application rates was monitored over a 2-year period using Salmonella/microsome mutagenicity assay. Samples were collected from undisturbed monolith lysimeters of Weswood sandy clay (Fluventic Ustochrept) and Padina sandy loam (Grossarenic Paleustalf) amended with dried sewage sludge at 50 and 100 Mg/ha. Soil samples were collected and sequentially extracted with methylene chloride and methanol. The residues from these extracts were tested for mutagenicity at five doses with and without metabolic activation in Salmonella strain TA98. In general, the mutagenic potential of the amended soils of both application rates for the first 8 weeks following sludge application increased and then slowly decreased. The maximum mutagenic response observed in the soil extracts was 222 revertants at a dose of 10 mg of residue. This response was induced by the methanol extract from the Weswood soil collected 56 days after the application of 50 Mg/ha sewage sludge as compared to the 100 Mg/ha application which induced 202 revertants/mg. The mutagenicity of all fractions extracted from the sludge-amended soil at both application rates collected 717 days after application were not appreciably different from extracts from the unamended soils. The data indicate that chemicals that were mutagenic in bacteria persist in the soil and that at the higher application rates, as much as 2 years may be required for the mutagenic potential of the soil to return to background levels.
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Affiliation(s)
- K C Donnelly
- Texas A & M University, Soil and Crop Sciences Department, College Station, TX 77843, USA
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Bartholomeusz RC, LaBrooy JT, Ey PL, Di Matteo AC, Daniels DA, Anderson CS, Rowley D. Assays for total and antigen-specific polymeric IgA in serum based on binding to secretory component. J Immunol Methods 1989; 117:247-55. [PMID: 2921529 DOI: 10.1016/0022-1759(89)90147-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Binding assays with secretory component (SC) were used to detect polymeric IgA antibody to E. coli lipopolysaccharide and to estimate total polymeric IgA in sera from 14 patients with alcoholic liver disease and eight normal controls. Radioiodinated human SC was shown to bind to polymeric IgA and IgM but not to monomeric IgA, secretory IgA or IgG. Serum aliquots (0.5 ml) were totally depleted of IgM using 2 ml anti-IgM affinity columns and the effluent sera were titrated in microtitre plates coated with lipopolysaccharide, the binding of polymeric IgA being detected by adding 10 ng radiolabelled SC. Total polymeric IgA was measured via its capacity to inhibit the binding of 5 ng labelled SC to IgM coated wells, quantitation being achieved by comparison with the inhibition produced by purified polymeric IgA. Total lipopolysaccharide-specific IgA antibody was detected by ELISA in sera from both patients and controls, 1185 +/- 793 and 56 +/- 19 U/100 microliters (mean +/- SD), respectively; but polymeric IgA antibody was detected only in patients' sera (131 +/- 214 U/100 microliters). The concentration of total polymeric IgA was higher in patients' sera than in control sera (488 +/- 333 and less than 120 micrograms/ml respectively).
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Abstract
Hypercalcemia is a common cause of morbidity in cancer patients. The mechanism of malignancy-associated hypercalcemia includes increased bone resorption and decreased renal calcium clearance which also occur in primary hyperparathyroidism. Norethisterone can inhibit bone resorption and has recently been shown to be effective treatment for mild hyperparathyroidism in post menopausal women. We report the successful use for the first time of norethisterone (5 mg daily) in a case of malignancy-associated hypercalcemia after other standard agents failed.
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Anderson CS, MacKinnon R, Smith C, Miller C. Charybdotoxin block of single Ca2+-activated K+ channels. Effects of channel gating, voltage, and ionic strength. J Gen Physiol 1988; 91:317-33. [PMID: 2454282 PMCID: PMC2216140 DOI: 10.1085/jgp.91.3.317] [Citation(s) in RCA: 212] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Charybdotoxin (CTX), a small, basic protein from scorpion venom, strongly inhibits the conduction of K ions through high-conductance, Ca2+-activated K+ channels. The interaction of CTX with Ca2+-activated K+ channels from rat skeletal muscle plasma membranes was studied by inserting single channels into uncharged planar phospholipid bilayers. CTX blocks K+ conduction by binding to the external side of the channel, with an apparent dissociation constant of approximately 10 nM at physiological ionic strength. The dwell-time distributions of both blocked and unblocked states are single-exponential. The toxin association rate varies linearly with the CTX concentration, and the dissociation rate is independent of it. CTX is competent to block both open and closed channels; the association rate is sevenfold faster for the open channel, while the dissociation rate is the same for both channel conformations. Membrane depolarization enhances the CTX dissociation rate e-fold/28 mV; if the channel's open probability is maintained constant as voltage varies, then the toxin association rate is voltage independent. Increasing the external solution ionic strength from 20 to 300 mM (with K+, Na+, or arginine+) reduces the association rate by two orders of magnitude, with little effect on the dissociation rate. We conclude that CTX binding to the Ca2+-activated K+ channel is a bimolecular process, and that the CTX interaction senses both voltage and the channel's conformational state. We further propose that a region of fixed negative charge exists near the channel's CTX-binding site.
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Affiliation(s)
- C S Anderson
- Graduate Department of Biochemistry, Brandeis University, Waltham, Massachusetts 02254
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