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[This corrects the article DOI: 10.5770/cgj.27.712.].
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OBJECTIVES: Long-term care (LTC) homes provide personal and medical care 24/7 to individuals unable to live at home due to illness or disability and are often the final place of care and death for their residents. Therefore, LTC homes are tasked with providing quality end-of-life care, often requiring injectable symptom management medications to relieve distressing symptoms (eg, pain). In this study, we aimed to understand the enablers and barriers to prescribing and administering end-of-life symptom management medications in LTC homes. DESIGN: Qualitative study. SETTING AND PARTICIPANTS: From February 2021 to December 2022, we conducted virtual semi-structured interviews with health care providers (physicians and nurses) who worked in Ontario LTC homes and family caregivers of residents who died in LTC. METHODS: We analyzed interview transcripts using thematic analysis. RESULTS: We identified 4 themes related to factors that may impact the prescribing and administering of medications for end-of-life symptom management: (1) identifying the end-of-life period and symptoms, (2) communication among health care providers and between health care providers and family caregivers, (3) health care provider competency with end-of-life medications, and (4) resources for LTC staff to support medication prescribing and administrating. CONCLUSIONS AND IMPLICATIONS: In LTC, there are distinct challenges in the prescribing and administrating of end-of-life symptom management medications. Our findings can be used to inform interventions aimed at improving end-of-life care for LTC residents. However, these interventions require buy-in and investment from the provincial government and the LTC sector.
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Long-Term Care , Nursing Homes , Qualitative Research , Terminal Care , Humans , Ontario , Male , Female , Middle Aged , Interviews as Topic , Caregivers/psychology , Aged , AdultABSTRACT
Background: At the end of life, individuals may experience physical symptoms such as pain, and guidelines recommend medications to manage these symptoms. Yet, little is known about the symptom management long-term care (LTC) residents receive at the end of life. Our research team developed a metric-whether residents receive one or more prescriptions for an end-of-life symptom management medication in their last two weeks-to explore end-of-life care for LTC residents. This qualitative study aimed to inform the refinement of the end-of-life prescribing metric, including the acceptability and applicability to assess the quality of a resident's symptom management at end-of-life. Methods: We conducted 14 semi-structured interviews with Ontario health-care providers (physicians and nurses) who work in LTC homes and family caregivers of residents who died in LTC. Interviews were conducted virtually between February 2021 and December 2022, and were analyzed using thematic analysis. Results: We identified three major themes relating to perceptions of the metric: 1) appropriateness, 2) health-care provider applicability, and 3) caregiver applicability. Participants noted that the metric may be appropriate to assess end-of-life care, but noted important nuances. Regarding applicability, health-care providers found value in the metric and that it could inform their practice. Conversely, caregivers found limited value in the metric. Conclusion: The proposed metric captures a very specific aspect of end-of-life care-whether end-of-life medications were prescribed or not. Participants deemed that the metric may reflect whether LTC homes have processes to manage a resident's end-of-life symptoms with medication. However, participants thought the metric could not provide a complete picture of end-of-life care and its quality.
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OBJECTIVE: To examine changes in the prescribing of end-of-life symptom management medications in long-term care (LTC) homes during the COVID-19 pandemic. DESIGN: Retrospective cohort study using routinely collected health administrative data in Ontario, Canada. SETTING AND PARTICIPANTS: We included all individuals who died in LTC homes between January 1, 2017, and March 31, 2021. We separated the study into 2 periods: before COVID-19 (January 1, 2017, to March 17, 2020) and during COVID-19 (March 18, 2020, to March 31, 2021). METHODS: For each LTC home, we measured the percentage of residents who died before and during COVID-19 who had a subcutaneous symptom management medication prescription in their last 14 days of life. We grouped LTC homes into quintiles based on their mean prescribing rates before COVID-19, and examined changes in prescribing during COVID-19 and COVID-19 outcomes across quintiles. RESULTS: We captured 75,438 LTC residents who died in Ontario's 626 LTC homes during the entire study period, with 19,522 (25.9%) dying during COVID-19. The mean prescribing rate during COVID-19 ranged from 46.9% to 79.4% between the lowest and highest prescribing quintiles. During COVID-19, the mean prescribing rate in the lowest prescribing quintile increased by 9.6% compared to before COVID-19. Compared to LTC homes in the highest prescribing quintile, homes in the lowest prescribing quintile experienced the highest proportion of COVID-19 outbreaks (73.4% vs 50.0%), the largest mean outbreak intensity (0.27 vs 0.09 cases/bed), the highest mean total days with a COVID-19 outbreak (72.7 vs 24.2 days), and the greatest proportion of decedents who were transferred and died outside of LTC (22.1% vs 8.6%). CONCLUSIONS AND IMPLICATIONS: LTC homes in Ontario had wide variations in the prescribing rates of end-of-life symptom management medications before and during COVID-19. Homes in the lower prescribing quintiles had more COVID-19 cases per bed and days spent in an outbreak.
Subject(s)
COVID-19 , Long-Term Care , Nursing Homes , SARS-CoV-2 , Terminal Care , Humans , COVID-19/epidemiology , Ontario/epidemiology , Female , Male , Retrospective Studies , Aged , Aged, 80 and over , Pandemics , Practice Patterns, Physicians'/statistics & numerical dataABSTRACT
OBJECTIVES: The Serious Illness Conversation Guide (SICG) has emerged as a framework for conversations with patients with a serious illness diagnosis. This study reports on narratives generated from open-ended questions of a novel assessment tool, the Serious Illness Conversation-Evaluation Exercise (SIC-Ex), to assess resident-led conversations with patients in oncology outpatient clinics. DESIGN: Qualitative study using template analysis. SETTING: Three academic cancer centres in Canada. PARTICIPANTS: 7 resident physicians (trainees), 7 patients from outpatient cancer clinics, 10 preceptors (raters) consisting of medical oncologists, palliative care physicians and radiation oncologists. INTERVENTIONS: Each trainee conducted an SIC with a patient, which was videotaped. The raters watched the videos and evaluated each trainee using the novel SIC-Ex and the reference Calgary-Cambridge Guide (CCG) initially and again 3 months later. Two independent coders used template analysis to code the raters' narrative comments and identify themes/subthemes. OUTCOME MEASURES: How narrative comments aligned with elements of the CCG and SICG. RESULTS: Template analysis yielded four themes: adhering to SICG, engaging patients and family members, conversation management and being mindful of demeanour. Narrative comments identified numerous verbal and non-verbal elements essential to SICG. Some comments addressing general skills in engaging patients/families and managing the conversation (eg, setting agenda, introduction, planning, exploring, non-verbal communication) related to both the CCG and SICG, whereas other comments such as identifying substitute decision maker(s), affirming commitment and introducing Advance Care Planning were specific to the SICG. CONCLUSIONS: Narrative comments generated by SIC-Ex provided detailed and nuanced insights into trainees' competence in SIC, beyond the numerical ratings of SIC-Ex and the general communication skills outlined in the CCG, and may contribute to a more fulsome assessment of SIC skills.
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Advance Care Planning , Physicians , Humans , Feedback , Communication , NarrationABSTRACT
BACKGROUND: Medications are often needed to manage distressing end-of-life symptoms (eg, pain, agitation). OBJECTIVES: In this study, we describe the variation in prescribing rates of symptom relief medications at the end of life among long-term care (LTC) decedents. We evaluate the extent these medications are prescribed in LTC homes and whether prescribing rates of end-of-life symptom management can be used as an indicator of quality end-of-life care. DESIGN: Retrospective cohort study using administrative health data. SETTING AND PARTICIPANTS: LTC decedents in all 626 publicly funded LTC homes in Ontario, Canada, between January 1, 2017, and March 17, 2020. METHODS: For each LTC home, we measured the percent of decedents who received 1+ prescription(s) for a subcutaneous end-of-life symptom management medication ("end-of-life medication") in their last 14 days of life. We then ranked LTC homes into quintiles based on prescribing rates. RESULTS: We identified 55,916 LTC residents who died in LTC. On average, two-thirds of decedents (64.7%) in LTC homes were prescribed at least 1 subcutaneous end-of-life medication in the last 2 weeks of life. Opioids were the most common prescribed medication (overall average prescribing rate of 62.7%). LTC homes in the lowest prescribing quintile had a mean of 37.3% of decedents prescribed an end-of-life medication, and the highest quintile mean was 82.5%. In addition, across these quintiles, the lowest prescribing quintile had a high average (30.3%) of LTC residents transferred out of LTC in the 14 days compared with the highest prescribing quintile (12.7%). CONCLUSIONS AND IMPLICATIONS: Across Ontario's LTC homes, there are large differences in prescribing rates for subcutaneous end-of-life symptom relief medications. Although future work may elucidate why the variability exists, this study provides evidence that administrative data can provide valuable insight into the systemic delivery of end-of-life care.
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Long-Term Care , Terminal Care , Humans , Retrospective Studies , Death , OntarioABSTRACT
Background: Palliative care (PC) is an added layer of support provided concurrently with cancer care and serves to improve wellbeing and sustain quality of life. Understanding what is meaningful and a priority to patients, their families, and caregivers with lived experience of cancer and PC is critical in supporting their needs and improving their care provision. However, the impacts of engaging cancer patients within the context of PC research remain unknown. Objective: To examine the impacts of engaging individuals with lived experience of cancer and PC as partners in PC research. Methods: An a priori systematic review protocol was registered with PROSPERO (CRD42021286744). Four databases (APA PsycINFO, CINAHL, EMBASE, and MEDLINE) were searched and only published, peer-reviewed primary English studies aligned with the following criteria were included: (1) patients, their families, and/or caregivers with lived experience of cancer and PC; (2) engaged as partners in PC research; and (3) reported the impacts of engaging cancer PC patient partners in PC research. We appraised the quality of eligible studies using the Critical Appraisal Skills Program (CASP) and GRIPP2 reporting checklists. Results: Three studies that included patient partners with lived experience of cancer and PC engaged at all or several of the research stages were identified. Our thematic meta-synthesis revealed impacts (benefits and opportunities) on patient partners (emotional, psychological, cognitive, and social), the research system (practical and ethical) and health care system (service improvements, bureaucratic attitudes, and inaction). Our findings highlight the paucity of evidence investigating the impacts of engaging patients, their families and caregivers with lived experience of cancer and PC, as partners in PC research. Conclusions: The results of this review and meta-synthesis can inform the more effective design of cancer patient partnerships in PC research and the development of feasible and effective strategies given the cancer and PC context patient partners are coming from.
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Despite the known benefits, healthcare systems struggle to provide early, integrated palliative care (PC) for advanced cancer patients. Understanding the barriers to providing PC from the perspective of oncology clinicians is an important first step in improving care. A 33-item online survey was emailed to all oncology clinicians working with all cancer types in Alberta, Canada, from November 2017 to January 2018. Questions were informed by Michie's Theoretical Domains Framework and Behaviour Change Wheel (BCW) and queried (a) PC provision in oncology clinics, (b) specialist PC consultation referrals, and (c) working with PC consultants and home care. Respondents (n = 263) were nurses (41%), physicians (25%), and allied healthcare professionals (18%). Barriers most frequently identified were "clinicians' limited time/competing priorities" (64%), "patients' negative perceptions of PC" (63%), and clinicians' capability to manage patients' social issues (63%). These factors mapped to all three BCW domains: motivation, opportunity, and capability. In contrast, the least frequently identified barriers were clinician motivation and perceived PC benefits. Oncology clinicians' perceptions of barriers to early PC were comparable across tumour types and specialties but varied by professional role. The main challenges to early integrated PC include all three BCW domains. Notably, motivation is not a barrier for oncology clinicians; however, opportunity and capability barriers were identified. Multifaceted interventions using these findings have been developed, such as tip sheets to enhance capability, reframing PC with patients, and earlier specialist PC nursing access, to enhance clinicians' use of and patients' benefits from an early PC approach.
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Medical Oncology , Neoplasms , Alberta , Humans , Neoplasms/therapy , Palliative Care , Surveys and QuestionnairesABSTRACT
BACKGROUND: In 2014, Alberta, Canada broke new ground in having the first provincial healthcare policy and procedure for advance care planning (ACP), the process of communicating and documenting a person's future healthcare preferences. However, to date public participation and awareness of ACP remains limited. The aim of this initiative was to elicit community group perspectives on how to help people learn about and participate in ACP. METHODS: Targeted invitations were sent to over 300 community groups in Alberta (e.g. health/disease, seniors/retirement, social/service, legal, faith-based, funeral planning, financial, and others). Sixty-seven participants from 47 community groups attended a "World Café". Participants moved between tables at fixed time intervals, and in small groups discussed three separate ACP-related questions. Written comments were captured by participants and facilitators. Each comment was coded according to Michie et al.'s Theoretical Domains Framework, and mapped to the Capability, Opportunity and Motivation behavior change system (COM-B) in order to identify candidate intervention strategies. RESULTS: Of 800 written comments, 76% mapped to the Opportunity: Physical COM-B component of behavior, reflecting a need for access to ACP resources. The most common intervention functions identified pertained to Education, Environmental Restructuring, Training, and Enablement. We synthesized the intervention functions and qualitative comments into eight recommendations for engaging people in ACP. These pertain to access to informational resources, group education and facilitation, health system processes, use of stories, marketing, integration into life events, inclusion of business partners, and harmonization of terminology. CONCLUSIONS: There was broad support for the role of community groups in promoting ACP. Eight recommendations for engaging the public in ACP were generated and have been shared with stakeholders.
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Advance Care Planning , Community Participation , Alberta , Awareness , Female , Health Services Needs and Demand , Humans , MaleABSTRACT
CONTEXT: Standardized outcomes that define successful advance care planning (ACP) are lacking. OBJECTIVE: The objective of this study was to create an Organizing Framework of ACP outcome constructs and rate the importance of these outcomes. METHODS: This study convened a Delphi panel consisting of 52 multidisciplinary, international ACP experts including clinicians, researchers, and policy leaders from four countries. We conducted literature reviews and solicited attendee input from five international ACP conferences to identify initial ACP outcome constructs. In five Delphi rounds, we asked panelists to rate patient-centered outcomes on a seven-point "not-at-all" to "extremely important" scale. We calculated means and analyzed panelists' input to finalize an Organizing Framework and outcome rankings. RESULTS: Organizing Framework outcome domains included process (e.g., attitudes), actions (e.g., discussions), quality of care (e.g., satisfaction), and health care (e.g., utilization). The top five outcomes included 1) care consistent with goals, mean 6.71 (±SD 0.04); 2) surrogate designation, 6.55 (0.45); 3) surrogate documentation, 6.50 (0.11); 4) discussions with surrogates, 6.40 (0.19); and 5) documents and recorded wishes are accessible when needed 6.27 (0.11). Advance directive documentation was ranked 10th, 6.01 (0.21). Panelists raised caution about whether "care consistent with goals" can be reliably measured. CONCLUSION: A large, multidisciplinary Delphi panel developed an Organizing Framework and rated the importance of ACP outcome constructs. Top rated outcomes should be used to evaluate the success of ACP initiatives. More research is needed to create reliable and valid measurement tools for the highest rated outcomes, particularly "care consistent with goals."
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Advance Care Planning , Outcome Assessment, Health Care/methods , Delphi Technique , HumansABSTRACT
BACKGROUND: Advance care planning (ACP) is a process of reflection on and communication of a person's future health-care preferences. Evidence suggests visible minorities engage less in ACP. The South Asian ethnic group is the largest visible minority group in Canada, and information is needed to understand how ACP is perceived and how best to approach ACP within this diverse community. OBJECTIVE: To explore perspectives of South Asian community members towards ACP. DESIGN: Peer-to-peer inquiry. South Asian community members who graduated from the Patient and Community Engagement Research programme (PaCER) at the University of Calgary utilized the PaCER method (SET, COLLECT and REFLECT) to conduct a focus group, family interviews and a community forum. SETTING AND PARTICIPANTS: Fifty-seven community-dwelling men and women (22-86 years) who self-identified with the South Asian community in Calgary, Alberta, Canada. RESULTS: The concept of ACP was mostly foreign to this community and was often associated with other end-of-life issues such as organ donation and estate planning. Cultural aspects (e.g. trust in shared family decision making and taboos related to discussing death), religious beliefs (e.g. fatalism) and immigration challenges (e.g. essential priorities) emerged as barriers to participation in ACP. However, participants were eager to learn about ACP and recommended several engagement strategies (e.g. disseminate information through religious institutions and community centres, include families in ACP discussions, encourage family physicians to initiate discussions and translate materials). CONCLUSIONS: Use of a patient engagement research model proved highly successful in understanding South Asian community members' participation in ACP.
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Advance Care Planning , Asian People/psychology , Perception , Adult , Aged , Aged, 80 and over , Asia, Western/ethnology , Canada/epidemiology , Communication , Cultural Characteristics , Female , Focus Groups , Humans , Male , Middle Aged , Qualitative Research , ReligionABSTRACT
Objectives Advance care planning is the process by which people reflect upon their wishes and values for healthcare, discuss their choices with family and friends and document their wishes. Readiness represents a key predictor of advance care planning participation; however, the evidence for addressing readiness is scarce within the renal failure context. Our objectives were to assess readiness for advance care planning and barriers and facilitators to advance care planning uptake in a renal context. Methods Twenty-five participants (nine patients, nine clinicians and seven family members) were recruited from the Southern Alberta Renal Program. Semi-structured interviews were recorded, transcribed and then analyzed using interpretive description. Results Readiness for advance care planning was driven by individual values perceived by a collaborative encounter between clinicians and patients/families. If advance care planning is not valued, then patients/families and clinicians are not ready to initiate the process. Patients and clinicians are delaying conversations until "illness burden necessitates," so there is little "advance" care planning, only care planning in-the-moment closer to the end of life. Discussion The value of advance care planning in collaboration with clinicians, patients and their surrogates needs reframing as an ongoing process early in the patient's illness trajectory, distinguished from end-of-life decision making.
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Advance Care Planning , Family/psychology , Health Personnel/psychology , Kidney Failure, Chronic/psychology , Patient Participation/psychology , Alberta , Decision Making , Female , Humans , Male , Qualitative Research , Terminal Care/psychologyABSTRACT
BACKGROUND: Advance care planning initiatives are being implemented across healthcare systems around the world, but how best to evaluate their implementation is unknown. AIM: To identify gaps and/or redundancies in current evaluative strategies to help healthcare systems develop future evaluative frameworks for ACP. DESIGN: Systematic review. METHODS: Peer-reviewed and gray literature searches were conducted till February 2015 to answer: "What methods have healthcare systems used to evaluate implementation of advance care planning initiatives?" A PICOS framework was developed to identify articles describing the implementation and evaluation of a health system-level advance care planning initiative. Outcome measures were mapped onto a conceptual quality indicator framework based on the Institute of Medicine and Donabedian models of healthcare quality. RESULTS: A total of 46 studies met inclusion criteria for analysis. Most articles reported on single parts of a healthcare system (e.g. continuing care). The most common outcome measures pertained to document completion, followed by healthcare resource use. Patient-, family-, or healthcare provider-reported outcomes were less commonly measured. Concordance measures (e.g. dying in place of choice) were reported by only 26% of studies. The conceptual quality indicator framework identified gaps and redundancies in measurement and is presented as a potential foundation from which to develop a comprehensive advance care planning evaluation framework. CONCLUSION: Document completion is frequently used to evaluate advance care planning program implementation; capturing the quality of care appears to be more difficult. This systematic review provides health system administrators with a comprehensive summary of measures used to evaluate advance care planning and may identify gaps in evaluation within their local context.
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Advance Care Planning/standards , Outcome and Process Assessment, Health Care/methods , Program Evaluation/methods , Humans , Quality Assurance, Health Care/methodsABSTRACT
PURPOSE: To determine whether different MR diffusion- and perfusion-weighted imaging (DWI and PWI) parameters are important in distinguishing lesion growth from the acute lesion and from oligemia. MATERIALS AND METHODS: MR DWI and PWI were acquired from thirteen patients. We defined three regions: (i) LESION - intersection of acute and final lesions, (ii) GROWTH - portion of final lesion not part of acute lesion, and (iii) OLIGEMIA - region of perfusion abnormality not part of either the acute or final lesions. We used logistic regression modeling to distinguish GROWTH from LESION and from OLIGEMIA on a voxel-wise basis using DWI- and PWI-based parameters. Final models were selected based on the Wald statistic and validated by cross-validation using the mean (+/- standard deviation) area under the curve (AUC) from receiver operating characteristic analysis. RESULTS: The final model for differentiating GROWTH from LESION included DWI, the apparent diffusion coefficient (ADC), cerebral blood flow (CBF) and tissue type (AUC = 0.939 +/- 0.028). The final model for differentiating GROWTH from OLIGEMIA included DWI, ADC, CBF, and time-to-peak (AUC = 0.793 +/- 0.106). CONCLUSION: Different MR parameters are important in differentiating lesion growth from acute lesion and from oligemia in acute ischemic stroke.
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Brain Ischemia/pathology , Diffusion Magnetic Resonance Imaging/methods , Stroke/pathology , Aged , Aged, 80 and over , Analysis of Variance , Area Under Curve , Cerebrovascular Circulation , Female , Humans , Logistic Models , Male , Middle AgedABSTRACT
BACKGROUND AND PURPOSE: Accuracy of intracranial magnetic resonance angiography (MRA) and reliability of interpretation are not well established compared to conventional selective catheter angiography. The purpose of this study was to determine the accuracy of MRA in evaluation of intracranial vessels in acute stroke and transient ischemic attack (TIA) patients METHODS: Twenty-nine patients (seven females, 22 males; median age 53) with acute stroke or TIA were enrolled into the study. All patients underwent both MRA using a 3 T clinical magnet and conventional angiography within 48 hours. Median time between MRA and angiography was 263 minutes. Conventional angiography preceded MRA in 15 cases. Fourteen patients received thrombolysis during MRA or angiography. National Institutes of Health Stroke Scale scores were obtained prior to the MR exam. One neuroradiologist rated all conventional angiograms, which were used as gold standard. Five observers, blinded to conventional angiography results and all clinical information except symptom side, rated the MR angiograms. Kappa statistics were used to assess reliability; contingency tables were used to assess accuracy of non-enhanced and enhanced MRA. RESULTS: Two hundred and fifty two intracranial vessels were assessed. Agreement between raters was good for both non-enhanced (kappa = 0.50) and gadolinium-enhanced (kappa = 0.46) images. There were a total of 26 vessels occluded by DSA. Overall, the non-enhanced MRA showed sensitivity of 84.2% (95% CI 60.4-96.6) and specificity of 84.6% (95% CI 78.6-89.4). The enhanced MRA showed sensitivity of 69.2 (95% CI 38.6-90.9) and specificity of 73.6 (95% CI 65.5-80.7). CONCLUSIONS: Magnetic resonance angiography is a good non-invasive screening tool for assessing intracranial vessel status in acute ischemic stroke. Angiography remains the gold standard for definitive assessment of the intracranial circulation.
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Angiography, Digital Subtraction , Brain/blood supply , Cerebral Angiography , Magnetic Resonance Angiography , Stroke/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Brain/diagnostic imaging , Female , Humans , Male , Middle Aged , Observer Variation , Sensitivity and SpecificityABSTRACT
BACKGROUND AND PURPOSE: Cerebral microhemorrhages (MHs) are common among patients presenting with acute ischemic stroke and may predict both subsequent ischemic and hemorrhagic strokes. METHODS: We prospectively studied patients with and without MHs presenting within 12 hours of their ischemic stroke or transient ischemic attack (TIA). A magnetic resonance (MR) scan was performed within 24 hours of symptom(s) onset. The primary outcome was disabling or fatal stroke at 18 months. RESULTS: An MR scan was done in 236 patients with acute ischemic stroke or TIA. Forty-five (19.1%) patients had an MH on a baseline MR scan. Patients with MHs were 2.8x (10.8% versus 4.0%; P=0.036) more likely to have a subsequent disabling or fatal stroke than patients without an MH. The risk of symptomatic intracerebral hemorrhage was not statistically significant among MH and non-MH patients (3.3% versus 0.8%; P=0.31). CONCLUSIONS: The presence of cerebral MH(s) in patients with acute ischemic stroke or TIA predicts recurrent disabling and fatal strokes. This risk is mainly assumed by recurrent ischemic strokes.
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Brain Ischemia/pathology , Cerebral Hemorrhage/pathology , Ischemic Attack, Transient/pathology , Microcirculation , Stroke/mortality , Age Factors , Aged , Cerebral Hemorrhage/metabolism , Diffusion Magnetic Resonance Imaging , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Models, Statistical , Proportional Hazards Models , Prospective Studies , Recurrence , Risk , Risk Factors , Time Factors , Treatment OutcomeABSTRACT
PURPOSE: To prospectively determine which diffusion-weighted magnetic resonance (MR) imaging technique (ie, conventional diffusion-weighted MR imaging [b = 1000 or 1500 sec/mm2] or fluid-inversion prepared diffusion [FLIPD] MR imaging [b = 1500 sec/mm2]) is most accurate in depicting acute ischemic stroke at 3 T. MATERIALS AND METHODS: The Health Research Ethics Board approved this study; written informed consent was provided by all participants or their surrogate. Diffusion-weighted MR imaging was performed in 75 consecutive patients (43 men, 32 women; mean age, 64.0 years) with acute ischemic stroke. Two experienced neuroradiologists determined the presence of hyperacute stroke lesions at diffusion-weighted MR imaging by locating areas of hyperintensity that corresponded to regions with a decreased diffusion coefficient. These findings were used as the reference standard. Four raters who were blinded to patient history assessed all images and apparent diffusion coefficient maps for the presence of changes that were consistent with acute ischemic stroke. Accuracy, sensitivity, specificity, negative predictive value, positive predictive value, and inter- and intrarater reliability scores were calculated for each technique. RESULTS: Specificity, positive predictive value, and accuracy were not significantly different among the techniques. FLIPD MR images obtained with a b value of 1500 sec/mm2 had decreased sensitivity for acute ischemic stroke (mean, 61.8%; 95% confidence interval [CI]: 55.4%, 67.9%) compared with conventional diffusion-weighted MR images obtained with a b value of either 1000 sec/mm2 (mean, 82.5%; 95% CI: 77.1%, 87.0%) or 1500 sec/mm2 (mean, 84.5%; 95% CI: 79.3%, 88.9%). FLIPD MR images also had decreased negative predictive value (mean, 96.5%; 95% CI: 95.7%, 97.2%) compared with conventional diffusion-weighted MR images obtained with a b value of either 1000 sec/mm2 (mean, 98.4%; 95% CI: 97.8%, 98.8%) or 1500 sec/mm2 (mean, 98.6%; 95% CI: 98.1%, 99.0%). Intra- and interrater reliability scores were generally excellent for all three techniques. CONCLUSION: FLIPD MR images obtained with a b value of 1500 sec/mm2 are less suitable for the detection of acute ischemic stroke owing to a decreased sensitivity and negative predictive value. The performance of the two conventional diffusion-weighted MR imaging techniques (b = 1000 and 1500 sec/mm2) was equivalent.
Subject(s)
Brain Ischemia/pathology , Diffusion Magnetic Resonance Imaging/methods , Stroke/pathology , Acute Disease , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Sensitivity and SpecificityABSTRACT
BACKGROUND AND PURPOSE: Transient ischemic attack (TIA) patients may deteriorate rapidly. MRI is being increasingly used to assess such patients. One possible mechanism of neurological worsening is the presence of perfusion abnormalities. We sought to identify what proportion of TIA patients had evidence of perfusion abnormalities on MRI. METHODS: TIA patients were prospectively enrolled and had a MRI completed as soon as possible. The images were assessed for the presence of perfusion abnormalities. RESULTS: Sixty-nine TIA patients were enrolled, and 62 had perfusion imaging. In 56 patients (81%), the symptoms had resolved before imaging. In 21 patients (33.9%), there was evidence of a perfusion abnormality defined by relative mean transit time delay. In 12 patients (19.4%), the perfusion abnormality was present despite having complete resolution of neurological symptoms. We found no relationship between the presence of a perfusion abnormality and the clinical outcome. CONCLUSIONS: A proportion of TIA patients have perfusion abnormalities evident on MRI.
Subject(s)
Ischemia/pathology , Ischemic Attack, Transient/diagnosis , Ischemic Attack, Transient/pathology , Magnetic Resonance Angiography/methods , Aged , Brain/pathology , Female , Humans , Male , Middle Aged , Multivariate Analysis , Perfusion , Regression Analysis , Time FactorsABSTRACT
We examined whether the presence of diffusion-weighted imaging (DWI) lesions and vessel occlusion on acute brain magnetic resonance images of minor stroke and transient ischemic attack patients predicted the occurrence of subsequent stroke and functional outcome. 120 transient ischemic attack or minor stroke (National Institutes of Health Stroke Scale < or = 3) patients were prospectively enrolled. All were examined within 12 hours and had a magnetic resonance scan within 24 hours. Overall, the 90-day risk for recurrent stroke was 11.7%. Patients with a DWI lesion were at greater risk for having a subsequent stroke than patients without and risk was greatest in the presence of vessel occlusion and a DWI lesion. The 90-day risk rates, adjusted for baseline characteristics, were 4.3% (no DWI lesion), 10.8% (DWI lesion but no vessel occlusion), and 32.6% (DWI lesion and vessel occlusion) (p = 0.02). The percentages of patients who were functionally dependent at 90 days in the three groups were 1.9%, 6.2%, and 21.0%, respectively (p = 0.04). The presence of a DWI lesion and a vessel occlusion on a magnetic resonance image among patients presenting acutely with a transient ischemic attack or minor stroke is predictive of an increased risk for future stroke and functional dependence.
Subject(s)
Diffusion Magnetic Resonance Imaging , Ischemic Attack, Transient/pathology , Severity of Illness Index , Stroke/pathology , Triage/methods , Acute Disease , Aged , Disability Evaluation , Female , Humans , Ischemic Attack, Transient/epidemiology , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Risk Factors , Stroke/epidemiologyABSTRACT
It is thought that gray and white matter (GM and WM) have different perfusion and diffusion thresholds for cerebral infarction in humans. We sought to determine these thresholds with voxel-by-voxel, tissue-specific analysis of co-registered acute and follow-up magnetic resonance (MR) perfusion- and diffusion-weighted imaging. Quantitative cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and apparent diffusion coefficient (ADC) maps were analyzed from nine acute stroke patients (imaging acquired within 6 h of onset). The average values of each measure were calculated for GM and WM in normally perfused tissue, the region of recovered tissue and in the final infarct. Perfusion and diffusion thresholds for infarction were determined on a patient-by-patient basis in GM and WM separately by selecting thresholds with equal sensitivities and specificities. Gray matter has higher thresholds for infarction than WM (P<0.009) for CBF (20.0 mL/100 g min in GM and 12.3 mL/100 g min in WM), CBV (2.4 mL/100 g in GM and 1.7 mL/100 g in WM), and ADC (786 x 10(-6) mm(2)/s in GM and 708 x 10(-6) mm(2)/s in WM). The MTT threshold for infarction in GM is lower (P=0.014) than for WM (6.8 secs in GM and 7.1 secs in WM). A single common threshold applied to both tissues overestimates tissue at risk in WM and underestimates tissue at risk in GM. This study suggests that tissue-specific analysis of perfusion and diffusion imaging is required to accurately predict tissue at risk of infarction in acute ischemic stroke.