ABSTRACT
BACKGROUND AND PURPOSE: The reduction of delay between onset and hospital arrival and adequate pre-hospital care of persons with acute stroke are important for improving the chances of a favourable outcome. The objective is to recommend evidence-based practices for the management of patients with suspected stroke in the pre-hospital setting. METHODS: The GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology was used to define the key clinical questions. An expert panel then reviewed the literature, established the quality of the evidence, and made recommendations. RESULTS: Despite very low quality of evidence educational campaigns to increase the awareness of immediately calling emergency medical services are strongly recommended. Moderate quality evidence was found to support strong recommendations for the training of emergency medical personnel in recognizing the symptoms of a stroke and in implementation of a pre-hospital 'code stroke' including highest priority dispatch, pre-hospital notification and rapid transfer to the closest 'stroke-ready' centre. Insufficient evidence was found to recommend a pre-hospital stroke scale to predict large vessel occlusion. Despite the very low quality of evidence, restoring normoxia in patients with hypoxia is recommended, and blood pressure lowering drugs and treating hyperglycaemia with insulin should be avoided. There is insufficient evidence to recommend the routine use of mobile stroke units delivering intravenous thrombolysis at the scene. Because only feasibility studies have been reported, no recommendations can be provided for pre-hospital telemedicine during ambulance transport. CONCLUSIONS: These guidelines inform on the contemporary approach to patients with suspected stroke in the pre-hospital setting. Further studies, preferably randomized controlled trials, are required to examine the impact of particular interventions on quality parameters and outcome.
Subject(s)
Emergency Medical Services/standards , Stroke/therapy , Consensus , Emergency Medical Technicians , Humans , Neurology , Stroke/diagnosisABSTRACT
AIM: To determine whether focussed radiology training in reporting stroke computed tomography angiography (CTA) improved diagnostic performance of general radiology specialty trainees staffing regional on call rotas. MATERIALS AND METHODS: A validated case archive (VCA) consisting of 50 hyperacute stroke CTA cases was developed for a full day course on CTA interpretation. Training days were organised ensuring all local trainees had a chance to attend. The rate of major and minor amendments by neuroradiology consultants were reviewed in 252 on-call radiology trainee reports. RESULTS: Before training, radiology trainees had a total discrepancy (reporting error) rate of 37%: 12% major, 25% minor. Following CTA training, the total discrepancy rate was not significantly reduced (34%) but there was a substantial reduction in major discrepancies to 4% (p=0.037; odds ratio=3.30, 95% confidence interval [CI]: 1.08 to 10.12). CONCLUSION: An intensive training course based on a hyperacute stroke VCA significantly reduced major discrepancies in stroke CTA interpretation for radiology trainees. The ability of radiology trainees to recognise large vessel occlusions and other significant findings improved.
Subject(s)
Clinical Competence/statistics & numerical data , Computed Tomography Angiography/methods , Radiologists/statistics & numerical data , Radiology/education , Stroke/diagnostic imaging , Humans , Internship and Residency/methods , Internship and Residency/statistics & numerical dataABSTRACT
OBJECTIVE: Communicating treatment risks and benefits to patients and their carers is central to clinical practice in modern healthcare. We investigated the challenges of risk communication by clinicians offering thrombolytic therapy for hyperacute stroke where treatment must be administered rapidly to maximise benefit. METHOD: Semistructured interviews with 13 clinicians from three acute stroke units involved in decision making and/or information provision about thrombolysis. We report on clinicians' accounts of communicating risks and benefits to patients and carers. Framework analysis was employed. RESULTS: We identified the major challenges facing clinicians in communicating risk in this context that is, disease complexity, patients' capacity and time constraints, and communicating quality of life after stroke. We found significant variation in the data on risks and benefits that clinicians provide, and ways these were communicated to patients. Clinicians' communication strategies varied and included practices such as: a phased approach to communicating information, being responsive to the patient and family and documenting information they gave to patients. CONCLUSIONS: Risk communication about thrombolysis involves complex uncertainties. We elucidate the challenges of effective risk communication in a hyperacute setting and identify the issues regarding variation in risk communication and the use of less effective formats for the communication of numerical risks and benefits. The paper identifies good practice, such as the phased transfer of information over the care pathway, and ways in which clinicians might be supported to overcome challenges. This includes standardised risk and benefit information alongside appropriate personalisation of risk communication. Effective risk communication in emergency settings requires presentation of high-quality data which is amenable to tailoring to individual patients' circumstances. It necessitates clinical skills development supported by personalised risk communication tools.
Subject(s)
Communication , Decision Making , Patient Education as Topic , Stroke/drug therapy , Thrombolytic Therapy , Attitude of Health Personnel , Hospital Units , Humans , Informed Consent , Interviews as Topic , Patient Participation , Physician-Patient Relations , Practice Patterns, Physicians' , Professional-Family Relations , Risk Assessment , United KingdomSubject(s)
CADASIL/epidemiology , CADASIL/genetics , Receptors, Notch/genetics , Adult , Cohort Studies , England/epidemiology , Exons/genetics , Female , Follow-Up Studies , Humans , Male , Middle Aged , Mutation/genetics , Pedigree , Prevalence , Receptor, Notch3ABSTRACT
OBJECTIVE: To examine whether prior statin use affects outcome and intracranial hemorrhage (ICH) rates in stroke patients receiving IV thrombolysis (IVT). METHODS: In a pooled observational study of 11 IVT databases, we compared outcomes between statin users and nonusers. Outcome measures were excellent 3-month outcome (modified Rankin scale 0-1) and ICH in 3 categories. We distinguished all ICHs (ICH(all)), symptomatic ICH based on the criteria of the ECASS-II trial (SICH(ECASS-II)), and symptomatic ICH based on the criteria of the National Institute of Neurological Disorders and Stroke (NINDS) trial (SICH(NINDS)). Unadjusted and adjusted odds ratios (OR) with 95% confidence intervals were calculated. RESULTS: Among 4,012 IVT-treated patients, 918 (22.9%) were statin users. They were older, more often male, and more frequently had hypertension, hypercholesterolemia, diabetes, coronary heart disease, and concomitant antithrombotic use compared with nonusers. Fewer statin users (35.5%) than nonusers (39.7%) reached an excellent 3-month outcome (OR(unadjusted) 0.84 [0.72-0.98], p = 0.02). After adjustment for age, gender, blood pressure, time to thrombolysis, and stroke severity, the association was no longer significant (0.89 [0.74-1.06], p = 0.20). ICH occurred by trend more often in statin users (ICH(all) 20.1% vs 17.4%; SICH(NINDS) 9.2% vs 7.5%; SICH(ECASS-II) 6.9% vs 5.1%). This difference was statistically significant only for SICH(ECASS-II) (OR = 1.38 [1.02-1.87]). After adjustment for age, gender, blood pressure, use of antithrombotics, and stroke severity, the OR(adjusted) for each category of ICH (ICH(all) 1.15 [0.93-1.41]; SICH(ECASS-II) 1.32 [0.94-1.85]; SICH(NINDS) 1.16 [0.87-1.56]) showed no difference between statin users and nonusers. CONCLUSION: In stroke patients receiving IVT, prior statin use was neither an independent predictor of functional outcome nor ICH. It may be considered as an indicator of baseline characteristics that are associated with a less favorable course.
Subject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hydroxymethylglutaryl-CoA Reductase Inhibitors/adverse effects , Stroke/drug therapy , Thrombolytic Therapy/methods , Aged , Aged, 80 and over , Female , Humans , Infusions, Intravenous , Intracranial Hemorrhages/chemically induced , Intracranial Hemorrhages/epidemiology , Male , Middle Aged , Prospective Studies , Stroke/epidemiology , Thrombolytic Therapy/adverse effects , Treatment OutcomeABSTRACT
Stroke is the major cause of disability in the community. Most strokes are due to blocked arteries in the brain. Evidence is accumulating that clot-busting drugs improve outcome after ischaemic stroke. Recombinant tissue plasminogen activator (rt-PA) is licensed for the treatment of selected patients within three hours of acute ischaemic stroke in many parts of the world, and stroke services are being developed so that eligible patients can receive this treatment as soon as possible after the onset of stroke symptoms. However, thrombolysis can cause bleeding into the brain, so the treatment should only be given when the benefits outweigh the risks. Controversy still exists about the risks and benefits in certain groups of patients, and there is variation in practice between stroke physicians, reflecting these uncertainties.
Subject(s)
Fibrinolytic Agents/therapeutic use , Stroke/drug therapy , Tissue Plasminogen Activator/therapeutic use , Acute Disease , Aged, 80 and over , Brain Ischemia , European Union , Fibrinolytic Agents/adverse effects , Humans , Randomized Controlled Trials as Topic , Risk Factors , Stroke/diagnosis , Time Factors , Tissue Plasminogen Activator/adverse effects , United KingdomABSTRACT
AIM: To describe the United Kingdom (UK) experience with thrombolytic therapy with intravenous alteplase (rt-PA) for stroke, as captured by the Implementation of Thrombolysis in Stroke (SITS) project. METHODS: The multinational Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) was an observational study to assess the safety and efficacy of thrombolytic therapy, when administered within the first 3 h after onset of ischaemic stroke. SITS-MOST was embedded within the Safe Implementation of Thrombolysis in Stroke-International Stroke Thrombolysis Register (SITS-ISTR), an internet-based, international monitoring registry for auditing the safety and efficacy of routine therapeutic use of thrombolysis in acute ischaemic stroke. We performed an analysis of data contributed to SITS-MOST and SITS-ISTR from UK centres. RESULTS: A total of 614 patients received thrombolysis for stroke between December 2002 and April 2006, 327 were registered to SITS-MOST and 287 to SITS-ISTR. Thirty-one centres treated patients in the UK, of which 23 registered patients in both SITS-MOST and SITS-ISTR and eight solely to SITS-ISTR. The median age from the UK SITS-MOST was identical to the non-UK SITS-MOST register: 68 years (IQR 59-75). The majority (96.1%) of patients from the UK were treated between 8.00 a.m. and 9.00 p.m., and only 18.4% were treated on weekend days, reflecting the difficulties of maintaining provision of a thrombolytic service out of hours. Median onset-to-treatment-time was 155 min (IQR 130-170 min) for the UK, compared to 140 min (IQR 114-165 min) for the non-UK SITS-MOST group (P < 0.001). UK SITS-MOST patients at baseline had more severe stroke in comparison with non-UK patients [median NIHSS 14.5 (IQR 9-19) vs. 12 (IQR 8-17) (P < 0.001)]. Forty-eight percent of UK patients achieved mRS of 0-2 (independence), compared to 55% of the non-UK SITS-MOST register. There was no significant difference in symptomatic intracerebral haemorrhage rate in the UK compared with the non-UK SITS-MOST patients [2.5% (95% CI 1.3-4.8) vs. 1.7% (95% CI 1.4-2.0) P = 0.28]. In the multivariate analysis, there was no statistically significant difference in any outcome between UK and non-UK SITS-MOST patients. CONCLUSION: Thrombolytic therapy for stroke has been implemented successfully at a small number of UK stroke centres, with patchy provision throughout the country. The low frequency of treatment out with office hours suggests deficient infrastructure to support delivery. UK patients tended to be more severely affected at baseline and to be treated later. Outcomes are comparable to those seen at the non-UK SITS centres.
Subject(s)
Fibrinolytic Agents/therapeutic use , Stroke/drug therapy , Thrombolytic Therapy , Tissue Plasminogen Activator/therapeutic use , Aged , Female , Humans , Injections, Intravenous , Male , Middle Aged , Time Factors , Treatment Outcome , United KingdomABSTRACT
BACKGROUND: Hypertension is associated with impaired cognitive function but the effect of antihypertensive treatment on cognitive function is unclear. METHODS: We investigated the effect of treatment of hypertension on cognition with the angiotensin-receptor-blocker, candesartan, in a placebo-controlled, double-blind, randomized controlled trial at one center participating in the Study on Cognition and Prognosis in the Elderly. A total of 257 older adults with hypertension (mean age 76 years, blood pressure 165 +/- 8/88 +/- 7 mm Hg) were recruited from general practice and treated with 8-16 mg candesartan or placebo once daily, for a mean follow-up period of 44 months. Additional antihypertensive therapy was permitted in both groups to achieve treatment targets. Cognitive function was measured using the Cognitive Drug Research computerized assessment battery, trail-making tests, and verbal fluency. Data from annual assessments were used to calculate individual coefficients of decline by regressing composite test scores over time for five cognitive domains. RESULTS: The blood pressure difference between groups at study close was 8/3 mm Hg. The candesartan group showed less decline in attention (0.004 vs -0.036, p = 0.04) and episodic memory (0.14 vs -0.22, p = 0.04) compared to placebo, a similar trend for speed of cognition (-2.3 vs -17.4, p = 0.15), but no differences in working memory (0.0014 vs 0.0010, p = 0.90) or executive function (-0.0031 vs -0.0023, p = 0.95). Effect sizes were in the small-to-moderate range. CONCLUSIONS: The potential for blood pressure-lowering with angiotensin-receptor-blockers to reduce the rate of decline of specific areas of cognitive function in older patients with hypertension warrants further investigation to determine clinical efficacy.
Subject(s)
Antihypertensive Agents/administration & dosage , Benzimidazoles/administration & dosage , Cognition Disorders/drug therapy , Cognition Disorders/etiology , Hypertension/complications , Hypertension/drug therapy , Tetrazoles/administration & dosage , Aged , Aged, 80 and over , Angiotensin II Type 1 Receptor Blockers/administration & dosage , Angiotensin II Type 1 Receptor Blockers/adverse effects , Angiotensins/metabolism , Antihypertensive Agents/adverse effects , Benzimidazoles/adverse effects , Biphenyl Compounds , Blood Pressure/drug effects , Blood Pressure/physiology , Cerebral Arteries/drug effects , Cerebral Arteries/metabolism , Cerebral Arteries/physiopathology , Cognition/drug effects , Cognition/physiology , Cognition Disorders/physiopathology , Double-Blind Method , Drug Administration Schedule , Female , Humans , Hypertension/physiopathology , Male , Neuropsychological Tests , Placebos , Tetrazoles/adverse effects , Treatment OutcomeABSTRACT
The demonstration of the ischaemic penumbra in animal models and the effectiveness of reperfusion therapy in humans led to considerable optimism for neuroprotection in acute stroke. Initial experience with failure of phase II and III trials led to the STAIR recommendations for pre-clinical and clinical studies. Review of pre-clinical studies suggests that selection of agents for clinical development may not have been optimal. The neuroprotective agent NXY-059 fulfilled pre-clinical and many clinical STAIR criteria but a second large phase III study failed to demonstrate any benefit. Many of the STAIR criteria have not been fulfilled in the development of recent neuroprotective agents. Other issues not addressed include the use of animal models more reflective of older stroke patients with physiological derangement, demonstration of drug distribution to the proposed site of action in humans, selection of patients with salvageable tissue, achieving very early treatment, refinement of measurement of neurological impairment and disability, and physiological optimization in proof of concept human studies. Increasing the number and quality of clinical centres undertaking acute stroke research, use of surrogate imaging markers and adaptive dose designs in phase II trials could improve the likelihood of identifying an effective neuroprotective. Neuroprotection in acute stroke remains a significant challenge but has not been clearly shown to be ineffective. Given the profound burden of stroke and limited applicability of reperfusion to currently at best 10% patients, further proof of concept studies of neuroprotection remain indicated with careful review of pre-clinical data and more rigorous phase II trial design.
Subject(s)
Stroke/drug therapy , Acute Disease , Animals , Biomarkers , Brain Ischemia/complications , Clinical Trials as Topic , Drug Evaluation, Preclinical , Humans , Reperfusion Injury/drug therapy , Stroke/etiologyABSTRACT
BACKGROUND AND PURPOSE: Intra-arterial fibrinolytic therapy is a promising treatment for acute ischemic stroke. Few data are available on its use in elderly patients. The purpose of this study was to compare the baseline characteristics, complications, and outcomes between intra-arterially treated ischemic stroke patients aged > or = 80 years and their younger counterparts. METHODS: Patients aged > or = 80 years (n = 33) were compared retrospectively with contemporaneous patients aged < 80 years (n = 81) from a registry of consecutive patients treated with intra-arterial thrombolysis over a 9-year period. RESULTS: The very elderly and younger cohorts were very similar in baseline characteristics, including pretreatment stroke severity (National Institutes of Health Stroke Scale [NIHSS] 17 versus 16), differing only in history of stroke/transient ischemic attack (42% versus 22%, P = .01) and weight (66.8 versus 75.8 kg; P = .02). Significant differences in recanalization (TIMI 2-3) rates could not be detected between the very elderly and younger patients (79% versus 68%, P = .10). Rates of major symptomatic hemorrhage (7% versus 8%) and any intracerebral hemorrhage (39% versus 37%) did not differ. Outcomes at 90 days showed lower rates of excellent functional outcome (mRS < or = 1, 26% versus 40%, P = .02) and survival (57% versus 80%, P = .01) among the very elderly. CONCLUSIONS: Intra-arterial fibrinolysis in the elderly can be accomplished with recanalization rates and hemorrhage rates equal to that in younger patients. Although mortality rates are higher and good functional outcomes are lower than in younger persons, nondisabling outcomes may be achieved in a quarter of patients. These findings suggest that the investigation and use of intra-arterial thrombolytic treatment in very elderly patients should not be avoided but pursued judiciously.
Subject(s)
Cerebral Infarction/drug therapy , Fibrinolytic Agents/therapeutic use , Intracranial Embolism/drug therapy , Thrombolytic Therapy , Tissue Plasminogen Activator/therapeutic use , Urokinase-Type Plasminogen Activator/therapeutic use , Adult , Age Factors , Aged , Aged, 80 and over , Cerebral Angiography , Cerebral Hemorrhage/chemically induced , Cerebral Hemorrhage/diagnosis , Cerebral Infarction/diagnosis , Cohort Studies , Female , Fibrinolytic Agents/adverse effects , Humans , Intracranial Embolism/diagnosis , Magnetic Resonance Imaging , Male , Middle Aged , Outcome Assessment, Health Care , Retrospective Studies , Thrombolytic Therapy/adverse effects , Tissue Plasminogen Activator/adverse effects , Tomography, X-Ray Computed , Urokinase-Type Plasminogen Activator/adverse effectsABSTRACT
BACKGROUND: Epidemiological evidence on the effects of magnesium on blood pressure is inconsistent. Metabolic and experimental studies suggest that magnesium may have a role in the regulation of blood pressure. OBJECTIVES: To evaluate the effects of magnesium supplementation as treatment for primary hypertension in adults. SEARCH STRATEGY: We searched the Cochrane Library, MEDLINE, EMBASE, Science Citation Index, ISI Proceedings, ClinicalTrials.gov, Current Controlled Trials, CAB abstracts, and reference lists of systematic reviews, meta-analyses and randomised controlled trials (RCTs) included in the review. SELECTION CRITERIA: Inclusion criteria were: 1) RCTs of a parallel or crossover design comparing oral magnesium supplementation with placebo, no treatment, or usual care; 2) treatment and follow-up >/=8 weeks; 3) participants over 18 years old, with raised systolic blood pressure (SBP) >/=140 mmHg or diastolic blood pressure (DBP) >/=85 mmHg; 4) SBP and DBP reported at end of follow-up. We excluded trials where: participants were pregnant; received antihypertensive medication which changed during the study; or magnesium supplementation was combined with other interventions. DATA COLLECTION AND ANALYSIS: Two reviewers independently abstracted data and assessed trial quality. Disagreements were resolved by discussion or a third reviewer. Random effects meta-analyses and sensitivity analyses were conducted. MAIN RESULTS: Twelve RCTs (n=545) with eight to 26 weeks follow-up met our inclusion criteria. The results of the individual trials were heterogeneous. Combining all trials, participants receiving magnesium supplements as compared to control did not significantly reduce SBP (mean difference: -1.3 mmHg, 95% CI: -4.0 to 1.5, I(2)=67%), but did statistically significantly reduce DBP (mean difference: -2.2 mmHg, 95% CI: -3.4 to -0.9, I(2)=47%). Sensitivity analyses excluding poor quality trials yielded similar results. Sub-group analyses and meta-regression indicated that heterogeneity between trials could not be explained by dose of magnesium, baseline blood pressure or the proportion of males among the participants. AUTHORS' CONCLUSIONS: In view of the poor quality of included trials and the heterogeneity between trials, the evidence in favour of a causal association between magnesium supplementation and blood pressure reduction is weak and is probably due to bias. This is because poor quality studies generally tend to over-estimate the effects of treatment. Larger, longer duration and better quality double-blind placebo controlled trials are needed to assess the effect of magnesium supplementation on blood pressure and cardiovascular outcomes.
Subject(s)
Blood Pressure/drug effects , Dietary Supplements , Hypertension/therapy , Magnesium/therapeutic use , Adult , Dietary Supplements/adverse effects , Humans , Magnesium/adverse effects , Randomized Controlled Trials as TopicABSTRACT
BACKGROUND: Previous research suggests that increasing dietary intakes of calcium, potassium or magnesium separately may reduce BP to a small degree over the short term. It is unclear whether increasing intakes of a combination of these minerals produces a larger reduction in BP. OBJECTIVES: To evaluate the effects of combined mineral supplementation as a treatment for primary hypertension in adults. SEARCH STRATEGY: We searched the Cochrane Library, MEDLINE, EMBASE, Science Citation Index, ISI Proceedings, ClinicalTrials.gov, Current Controlled Trials, CAB abstracts, and reference lists of systematic reviews, meta-analyses and randomised controlled trials (RCTs) included in the review. The search was unrestricted by language or publication status. SELECTION CRITERIA: Inclusion criteria were: 1) RCTs of a parallel or crossover design comparing oral supplements comprising a combination of potassium, and/or calcium, and/or magnesium with placebo, no treatment, or usual care; 2) treatment and follow-up >=8 weeks; 3) participants over 18 years old, with raised systolic blood pressure (SBP) >=140 mmHg or diastolic blood pressure (DBP) >=85 mmHg with no known primary cause; 4) SBP and DBP reported at end of follow-up. We excluded trials where participants were pregnant, or received antihypertensive medication which changed during the study. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed trial quality. Disagreements were resolved by discussion or a third reviewer. Random effects meta-analyses and sensitivity analyses were conducted. MAIN RESULTS: We included three RCTs (n=277) with between 24 and 28 weeks follow-up. Three combinations of minerals were investigated: potassium & magnesium, calcium & magnesium, and calcium & potassium. One trial investigated combinations of calcium & magnesium and of calcium & potassium, and for each found a statistically non-significant increase in both SBP and DBP. All three trials investigated the combination of potassium & magnesium. None of the trials provided data on mortality or morbidity. The combination of potassium & magnesium compared to control resulted in statistically non-significant reductions in both SBP (mean difference = -4.6 mmHg, 95% CI: -9.9 to 0.7) and DBP (mean difference = -3.8 mmHg, 95% CI: -9.5 to 1.8), although the results were heterogeneous (I(2)=68% and 85% for SBP and DBP respectively).A sensitivity analysis using alternative reported values which accounted for missing data had very little effect on DBP but resulted in a larger, statistically significant reduction in SBP (mean difference = -5.8 mmHg, 95% CI: -10.5 to -1.0). The quality of the trials was not well reported. AUTHORS' CONCLUSIONS: We found no robust evidence that supplements of any combination of potassium, magnesium or calcium reduce mortality, morbidity or BP in adults. More trials are needed to investigate whether the combination of potassium & magnesium is effective.
Subject(s)
Calcium, Dietary/administration & dosage , Dietary Supplements , Hypertension/therapy , Magnesium/administration & dosage , Potassium, Dietary/administration & dosage , Adult , Blood Pressure/drug effects , Drug Therapy, Combination , HumansABSTRACT
The assessment of circadian blood pressure change by ambulatory blood pressure monitoring has potential as a predictor for cardiovascular events, but its evaluation is problematic due to the difficulty in defining day and night periods for individual subjects. The cumulative sums (cusums) method has the advantage of simplicity over mathematical modelling techniques and is reported to give more reproducible results than methods that use time-dependent sleep and wake periods. However, cusum parameters (cusum-derived circadian alteration magnitude (CDCAM) and cusum plot height (CPH)) are affected by the implementation of the method and by the quality of ambulatory blood pressure recordings. This study quantifies the effects of using interval blood pressure values, changing the time used for calculating the cusum plot slope (CPS) and using incomplete data recordings. Significant effects are reported in all cases. Using interval rather than recorded blood pressures causes a mean reduction in CPH and CDCAM of approximately 6%. Altering the CPS time by 1 h (from 6 h) results in a mean change in CDCAM of approximately 7%. In recordings with hourly readings, the coefficient of variation in CPH and CDCAM ranges from 4% (one missing reading) to 13% (five missing readings).
Subject(s)
Blood Pressure Determination/methods , Blood Pressure , Circadian Rhythm , Diagnosis, Computer-Assisted/methods , Hypertension/diagnosis , Hypertension/physiopathology , Monitoring, Ambulatory/methods , Aged , Aged, 80 and over , Artifacts , Female , Humans , Male , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
BACKGROUND: Metabolic studies suggest calcium may have a role in the regulation of blood pressure. Some epidemiological studies have reported that people with a higher intake of calcium tend to have lower blood pressure. Previous systematic reviews and meta-analyses have reached conflicting conclusions about whether oral calcium supplementation can reduce blood pressure. OBJECTIVES: To evaluate the effects of oral calcium supplementation as a treatment for primary hypertension in adults. SEARCH STRATEGY: We searched the Cochrane Library, MEDLINE, EMBASE, Science Citation Index, ISI Proceedings, ClinicalTrials.gov, Current Controlled Trials, CAB abstracts, and reference lists of systematic reviews, meta-analyses and randomised controlled trials (RCTs) included in the review. SELECTION CRITERIA: Inclusion criteria were: 1) RCTs comparing oral calcium supplementation with placebo, no treatment, or usual care; 2) treatment and follow-up >/=8 weeks; 3) participants over 18 years old, with raised systolic blood pressure (SBP) >/=140 mmHg or diastolic blood pressure (DBP) >/=85 mmHg; 4) SBP and DBP reported at end of follow-up. We excluded trials where: participants were pregnant; received antihypertensive medication which changed during the study; or calcium supplementation was combined with other interventions. DATA COLLECTION AND ANALYSIS: Two reviewers independently abstracted data and assessed trial quality. Disagreements were resolved by discussion or a third reviewer. Random effects meta-analyses and sensitivity analyses were conducted. MAIN RESULTS: We included 13 RCTs (n=485), with between eight and 15 weeks follow-up. The results of the individual trials were heterogeneous. Combining all trials, participants receiving calcium supplementation as compared to control had a statistically significant reduction in SBP (mean difference: -2.5 mmHg, 95% CI: -4.5 to -0.6, I(2 )= 42%), but not DBP (mean difference: -0.8 mmHg, 95% CI: -2.1 to 0.4, I(2) = 48%). Sub-group analyses indicated that heterogeneity between trials could not be explained by dose of calcium or baseline blood pressure. Heterogeneity was reduced when poor quality trials were excluded. The one trial reporting adequate concealment of allocation and the one trial reporting adequate blinding yielded results consistent with the primary meta-analysis. AUTHORS' CONCLUSIONS: In view of the poor quality of included trials and the heterogeneity between trials, the evidence in favour of causal association between calcium supplementation and blood pressure reduction is weak and is probably due to bias. This is because poor quality studies generally tend to over-estimate the effects of treatment. Larger, longer duration and better quality double-blind placebo controlled trials are needed to assess the effect of calcium supplementation on blood pressure and cardiovascular outcomes.
Subject(s)
Calcium, Dietary/therapeutic use , Dietary Supplements , Hypertension/therapy , Adult , Humans , Randomized Controlled Trials as TopicABSTRACT
OBJECTIVE: To present the preliminary experience of implementing intravenous thrombolytic therapy for acute ischaemic stroke in three UK stroke centres. BACKGROUND: Recombinant tissue plasminogen activator for ischaemic stroke received approval from UK regulatory authorities in April 2003. Since 1997, a small number of UK centres had used thrombolytic therapy in highly selected stroke patients. We present the early experience of that treatment in Glasgow and Newcastle. DESIGN: Patients were selected and treated in accordance with the American Heart Association guidelines. Additionally, radiologic criteria employed in the European-Australasian Acute Stroke Studies were applied. National Institutes of Health Stroke Scale (NIHSS) scores were measured on admission, and Modified Rankin Scale (MRS) scores were assessed at 3 months for all patients with stroke treated prior to initiation of the Safe Implementation of Thrombolysis in Stroke monitoring program for implementation of thrombolysis in stroke in April 2001. Intracranial and systemic haemorrhagic complications were recorded. RESULTS: 120 patients received thrombolytic treatment (approximately 1% of all admissions with presumed stroke). Mean age was 69 years (range 22-93) and initial median NIHSS score was 17 (range 3-31). In the two centres for which temporal data were available, the mean delay between symptom onset and treatment was 139 min (range 20-185). Sixteen episodes of cerebral haemorrhage or haemorrhagic transformation of any degree occurred, of which 5 (4%) were symptomatic. One patient deteriorated and died before repeat CT imaging could be performed. One non-fatal episode of systemic bleeding occurred. One patient was lost to follow-up. At 3 months, 31% of recipients had achieved good (MRS 0-1) outcome, 22% moderate (MRS 2-3) outcome and 21% (MRS 4-5) poor outcome. Twenty-one per cent died within 3 months of stroke. Observed frequency of bleeding complications and protocol violations (6%) was similar to those reported elsewhere. CONCLUSION: A small proportion of stroke patients received thrombolytic treatment. Patients treated were more severely affected than in other published European and North American series. Outcomes and complications were consistent with experience elsewhere.
Subject(s)
Brain Ischemia/therapy , Plasminogen Activators/therapeutic use , Stroke/therapy , Thrombolytic Therapy , Tissue Plasminogen Activator/therapeutic use , Acute Disease , Aged , Brain Ischemia/complications , Brain Ischemia/mortality , Female , Humans , Injections, Intravenous , Male , Middle Aged , Plasminogen Activators/administration & dosage , Prospective Studies , Recombinant Proteins/administration & dosage , Recombinant Proteins/therapeutic use , Stroke/etiology , Stroke/mortality , Tissue Plasminogen Activator/administration & dosage , Tomography, X-Ray Computed , Treatment Outcome , United KingdomABSTRACT
OBJECTIVE: To determine the potential role of whole brain atrophy, hippocampal atrophy, or both, and small vessel disease/white matter lesions as mechanisms underlying the cognitive impairment associated with hypertension. METHODS: Using MRI scanning the authors determined hippocampal volumes, whole brain volumes, and location and severity of white matter lesions, using Scheltens scale, in 103 hypertensive (166 +/- 8/88 +/- 7 mm Hg, 54 female) and 51 normotensive (132 +/- 12/74 +/- 7 mm Hg, 21 female) subjects age > or = 70 years. RESULTS: Compared to normotensive subjects, older hypertensive subjects had significantly smaller whole brain volumes (887 +/- 109 vs 930 +/- 97 cm3, p = 0.02) and nonsignificantly reduced hippocampal volumes (5.39 +/- 1.60 vs 5.67 +/- 1.80 cm3, p = 0.33). Hypertensive subjects had an increased burden of periventricular lesions: bands (p = 0.03), frontal caps (p = 0.08), occipital caps (p = 0.07), and total periventricular hyperintensities (p = 0.02). They also had higher scores in subcortical areas: frontal (p = 0.04), temporal (p = 0.03), and deep white matter areas (p = 0.05). A correlation was found between whole brain volumes and systolic blood pressure (r = -0.19, p = 0.02). No correlation was seen between whole brain volumes and white matter lesion burden. CONCLUSIONS: Moderate hypertension in non-impaired older subjects is associated with smaller whole brain volume and an increased burden of subcortical and periventricular white matter lesions.
Subject(s)
Brain/pathology , Cognition Disorders/etiology , Hippocampus/pathology , Hypertension/psychology , Myelin Sheath/pathology , Aged , Aged, 80 and over , Antihypertensive Agents/pharmacology , Antihypertensive Agents/therapeutic use , Atrophy , Blood Pressure , Cognition Disorders/pathology , Female , Humans , Hypertension/drug therapy , Hypertension/pathology , Magnetic Resonance Imaging , Male , Organ Size/drug effectsABSTRACT
BACKGROUND AND PURPOSE: Patients with suspected stroke first assessed by ambulance paramedics require early recognition to facilitate appropriate triage and early treatment. We determined paramedic's accuracy in detecting acute stroke signs by comparing agreement between neurological signs recorded in the Face Arm Speech Test (FAST), a stroke recognition instrument, by paramedics on the scene and by stroke physicians after admission. METHODS: Suspected stroke patients admitted by ambulance paramedics directly to an acute stroke unit through a rapid ambulance protocol were examined by a trainee stroke neurologist or admitting stroke physician over a 1-year period. Recorded neurological signs (facial weakness, arm weakness, speech disturbance) in confirmed acute stroke/transient ischemic attack (TIA) cases were compared between paramedics and the stroke neurologist/physician. RESULTS: Ambulance crews referred 278 suspected stroke patients of whom 217 (78%) had confirmed stroke (n=189) or TIA (n=28); 95% were examined by the stroke neurologist (median 18 hours after paramedic assessment). Recorded signs and agreement between paramedics and stroke physicians in confirmed stroke group were: facial weakness, 68% versus 70% (kappa=0.49; 95% CI: 0.36 to 0.62); arm weakness, 96% versus 95% (kappa=0.77; 95% CI: 0.55 to 0.99); and speech disturbance, 79% versus 77% (kappa=0.69; 95% CI: 0.56 to 0.82). Interrater agreement was complete for arm weakness in 98% cases. CONCLUSIONS: Recognition of neurological deficits by ambulance paramedics using FAST shows good agreement with physician assessment, even allowing for temporal evolution of deficits. The high prevalence and good agreement for arm weakness suggest that this sign may have the greatest usefulness for prehospital ambulance triage and paramedic-based neuroprotective trials.
Subject(s)
Emergency Medical Services/methods , Stroke/diagnosis , Acute Disease , Aged , Arm , Emergency Medical Technicians , Face , Female , Humans , Male , Muscle Weakness/diagnosis , Neurologic Examination , Observer Variation , Physicians , Speech Disorders/diagnosisABSTRACT
Stroke and dementia represent a major health burden for elderly subjects as they are associated with significant morbidity and mortality. The rates of stroke and dementia are progressively increasing due to the ageing population in most westernized countries. Therefore, both these conditions represent a major therapeutic target. However, the therapeutic options available for the management of stroke and dementia remain largely unsatisfactory, the main reason being the difficulty in transferring the results obtained in animal and in vitro studies to the clinical setting. This review focuses on the recent advances in pathophysiology and treatment of these conditions and future directions for research. Moreover, the technique of functional magnetic resonance imaging is discussed in detail as a tool to assess the effects of therapeutic agents on the central nervous system and monitor the progression of diseases. Finally, an overview of the issue of drug delivery into the central nervous system is presented.