Do studies of the weekend effect really allow for differences in illness severity? An analysis of 14 years of stroke admissions.

Background: An increased mortality rate among patients admitted to hospital at weekends has been found in many studies, and this 'weekend effect' has been used to justify major health service reorganisation. Most studies have used routine administrative data to adjust for potential confounding factors, and are unable to measure differences in illness severity due to the tendency of patients with milder symptoms to stay home at weekends. We set out to estimate the importance of such unmeasured 'confounding by severity', using data from a hospital stroke register. Methods: All suspected acute stroke admissions in Gateshead were prospectively registered over a period of 14.3 years, including information on premorbid factors, measures of stroke severity and survival to hospital discharge. We examined whether each factor differed between weekday and weekend admissions, then used logistic regression to estimate the main contributors to variation in mortality rates. Results: Stroke severity, measured by the Scandinavian Stroke Scale (SSS), was significantly greater among weekend admissions and strongly associated with mortality, and after adjustment for SSS score in logistic regression, the weekend effect completely disappeared. By contrast, most indicators of pre-stroke function, comorbidity or stroke type did not differ between weekday and weekend admissions, although some of them had prognostic significance. Conclusions: The sorts of factors measurable in administrative databases only account for a small part of the prognostically important differences in case-mix between weekday and weekend stroke admissions. While increasing weekend staffing might improve adherence to care standards, evidence that it could save lives is unreliable.

Very early rehabilitation or intensive telemetry after stroke: a pilot randomised trial.

BACKGROUND: Stroke patients are more likely to make a good recovery if they receive care in a well-organised stroke unit. However, there are uncertainties about how best to provide such care. We studied 2 key aspects of early stroke unit care: early active mobilisation (EM) and automated monitoring (AM) for physiological complications such as hypoxia. METHODS: This was an observer-blinded, factorial (2 x 2) pilot randomised controlled trial recruiting stroke patients within 36 h of symptom onset. The patients were randomised to 1 of 4 nurse-led treatment protocols: (a) standard stroke unit care, (b) EM, (c) AM or (d) combined EM and AM. The primary outcome was the Rankin score at 3 months. We also report the data on feasibility and safety. RESULTS: We randomised 32 patients (mean age = 65 years; mean baseline modified NIH score = 6). On unadjusted comparisons, the EM patients were significantly (p < 0.05) more likely to mobilise very early (within 1 h of randomisation) and to achieve walking by day 5 and were less likely to develop complications of immobility. The AM group was significantly (p < 0.05) more likely to have pre-defined physiological complication events detected. All these associations remained, but were less statistically significant, after correcting for age, baseline NIH score and co-interventions. There were no significant safety concerns. DISCUSSION: We have demonstrated the feasibility of implementing EM and AM for physiological complications in a randomised controlled trial. Larger trials are warranted to determine whether these interventions have clinical benefits.

Mood after stroke: a case control study of biochemical, neuro-imaging and socio-economic risk factors for major depression in stroke survivors.

BACKGROUND: Though vascular factors may be important in the aetiology of late-life depression, it is not clear whether they have a major effect on the risk of depression after a stroke. We investigated the relationship between physiological, biochemical, neuro-imaging and socio-economic factors and late-phase post-stroke depression in a cross-sectional case-control study. METHODS: People living at home at least 9 months after a stroke were interviewed using a structured proforma. Depression was diagnosed according to DSM-IV criteria, together with a Montgomery Asberg (MADRS) score >17. Stroke survivors of similar age and functional status but without symptoms of, or recent treatment for, depression and with MADRS score <7, were recruited as controls. RESULTS: Stroke survivors with depression were more likely than controls to have been smokers, to have had hypertension or peripheral arterial disease, and to have had more than one stroke or multiple discrete brainscan lesions. In univariate analysis they had significantly higher blood pressure, lower Mini-Mental State (MMSE) scores, higher serum homocysteine and lower folate levels, as well as more extensive white matter and basal ganglia changes on brainscan. In logistic regression, previous hypertension (OR 3.4), peripheral vascular disease (OR 4.7), number of strokes (OR 2), MMSE score (OR 0.76) and basal ganglia changes (OR 2.2), were independently associated with depression. CONCLUSION: These results suggest that patients with hypertension, hyperhomocysteinaemia and other factors associated with cerebral small vessel disease, may be more susceptible to post-stroke depression. Future intervention trials should focus on such high risk groups.

Motivational interviewing for low mood and adjustment early after stroke: a feasibility randomised trial.

BACKGROUND: Management of psychological adjustment and low mood after stroke can result in positive health outcomes. We have adapted a talk-based therapy, motivational interviewing (MI), and shown it to be potentially effective for managing low mood and supporting psychological adjustment post-stroke in a single-centre trial. In the current study, we aimed to explore the feasibility of delivering MI using clinical stroke team members, and using an attention control (AC), to inform the protocol for a future definitive trial. METHODS: This parallel two-arm feasibility trial took place in north-west England. Recruitment occurred between December 2012 and November 2013. Participants were stroke patients aged 18 years or over, who were medically stable, had no severe communication problems, and were residents of the hospital catchment. Randomisation was to MI or AC, and was conducted by a researcher not involved in recruitment using opaque sealed envelopes. The main outcome measures were descriptions of study feasibility (recruitment/retention rates, MI delivery by clinical staff, use of AC) and acceptability (through qualitative interviews and completion of study measures), and fidelity to MI and AC (through review of session audio-recordings). Information was also collected on participants' mood, quality of life, adjustment, and resource-use. RESULTS: Over 12 months, 461 patients were screened, 124 were screened eligible, and 49 were randomised: 23 to MI, 26 to AC. At 3 months, 13 MI and 18 AC participants completed the follow-up assessment (63% retention). This was less than expected based on our original trial. An AC was successfully implemented. Alternative approaches would be required to ensure the feasibility of clinical staff delivering MI. The study measures, MI, and AC interventions were considered acceptable, and there was good fidelity to the interventions. There were no adverse events related to study participation. CONCLUSIONS: It was possible to recruit and retain participants, train clinical staff to deliver MI, and implement an appropriate AC. Changes would be necessary to conduct a future multi-centre trial, including: assuming a recruitment rate lower than that in the current study; implementing more strategies to increase participant retention; and considering alternative clinical staff groups to undertake the delivery of MI and AC. TRIAL REGISTRATION: ISRCTN study ID: ISRCTN55624892. TRIAL FUNDING: Northern Stroke Research Fund.

Thrombolytic Treatment for Ischaemic Stroke: Could the Crisis of Confidence Have Been Avoided by Better Analysis of Trial Data?

In many countries, thrombolysis with intravenous alteplase has become a central part of acute stroke care in recent years, requiring radical restructuring of services. However, a significant minority of emergency and stroke physicians have always had serious doubts about the safety and efficacy of thrombolytic treatment, and in 2015 these prompted a major review of the licensing status of alteplase by the UK regulatory authorities. Subsequent dramatic headlines and media stories have called into question the integrity of researchers and clinicians and undermined public faith in medical research. How did this situation arise and what should be done to prevent a repetition as we enter the era of intra-arterial treatment for stroke?Early intravenous alteplase increases the chances both of good recovery and of severe haemorrhage, so the risk/benefit balance must be assessed for individual patients according to stroke severity. For older patients and those with bigger strokes, the 'good recovery' criterion is an inefficient way of assessing treatment effects since few achieve full independence and differences between levels of functional impairment are ignored. This waste of information can be reduced by applying different criteria for 'good' and 'poor' outcomes in different prognostic groups (as clinicians do intuitively), hence increasing the number of patients contributing useful data. Such 'three-way prognosis-based outcome' analysis of existing and future trials could greatly increase the amount of relevant evidence to guide clinical decisions for individual patients across the range of stroke severity.

Early surgery versus initial conservative treatment in patients with spontaneous supratentorial intracerebral haematomas in the International Surgical Trial in Intracerebral Haemorrhage (STICH): a randomised trial.

BACKGROUND: Spontaneous supratentorial intracerebral haemorrhage accounts for 20% of all stroke-related sudden neurological deficits, has the highest morbidity and mortality of all stroke, and the role of surgery remains controversial. We undertook a prospective randomised trial to compare early surgery with initial conservative treatment for patients with intracerebral haemorrhage. METHODS: A parallel-group trial design was used. Early surgery combined haematoma evacuation (within 24 h of randomisation) with medical treatment. Initial conservative treatment used medical treatment, although later evacuation was allowed if necessary. We used the eight-point Glasgow outcome scale obtained by postal questionnaires sent directly to patients at 6 months follow-up as the primary outcome measure. We divided the patients into good and poor prognosis groups on the basis of their clinical status at randomisation. For the good prognosis group, a favourable outcome was defined as good recovery or moderate disability on the Glasgow outcome scale. For the poor prognosis group, a favourable outcome also included the upper level of severe disability. Analysis was by intention to treat. FINDINGS: 1033 patients from 83 centres in 27 countries were randomised to early surgery (503) or initial conservative treatment (530). At 6 months, 51 patients were lost to follow-up, and 17 were alive with unknown status. Of 468 patients randomised to early surgery, 122 (26%) had a favourable outcome compared with 118 (24%) of 496 randomised to initial conservative treatment (odds ratio 0.89 [95% CI 0.66-1.19], p=0.414); absolute benefit 2.3% (-3.2 to 7.7), relative benefit 10% (-13 to 33). INTERPRETATION: Patients with spontaneous supratentorial intracerebral haemorrhage in neurosurgical units show no overall benefit from early surgery when compared with initial conservative treatment.

Design and analysis of phase III trials with ordered outcome scales: the concept of the sliding dichotomy.

The conventional approach to the analysis of a Phase III trial in head injury or stroke takes an ordered scale measuring functional outcome and collapses the scale to a binary outcome of favorable versus unfavorable. This discards potentially relevant information which limits statistical power and moreover is not in accord with clinical practice. We propose an alternative approach where a favorable outcome is defined as better than would be expected, taking account of each individual patient's baseline prognosis. This is illustrated through a worked example based on data from a Phase III trial in head injury. The approach is also compared with the proportional odds model, which is another statistical approach that can exploit an ordered outcome scale. The approach raises issues of clinical, statistical, and regulatory importance, and we initiate what we believe needs to become a widespread debate amongst the community involved in clinical research in head injury and stroke.

Hypoxia of sleep apnoea: cardiopulmonary and cerebral changes after intermittent hypoxia in rats.

Sleep apnoea (SA) is common, especially in elderly people. In severe cases, arterial P(O2) may be lowered for a third or more in a night of sleep. To simulate the degree and duration of severe SA we exposed rats in a normobaric environmental chamber to 10% O(2) for 4h daily for 56 days (intermittent hypoxia: IH group) and compared them with rats continuously exposed for 8 weeks (continuous hypoxia: CH group) and control rats breathing room air (normoxic: N group). We found significant cardiopulmonary and cerebral changes. Right ventricular hypertrophy developed in IH and to a greater extent in CH. Small peripheral lung vessels developed thicker walls (assessed by a new method), which reduced their lumen, more in CH than IH. Coronal brain sections were immunostained for the glucose-transporter 1 (GLUT1) and the vascular endothelial growth factor (VEGF). The percentages of immunoreactivity in the frontal and temporal cortex, hippocampus, accumbens and putamen were determined by image-capture analysis. We noted GLUT1 immunoreactivity of the capillaries was similarly increased in all regions after CH but less so after IH. However, there was a significant linear trend in GLUT1 reactivity from N to IH to CH (R(2) = 0.73, P = 0.007) that was also confirmed by analysis of variance. The extent of VEGF-stained neurones and glial cells was significantly increased in all regions after IH but not after CH. This suggests that the signals for angiogenesis were complete or arrested after CH. Our findings have implications for the elderly subjected to hypoxic episodes during sleep apnoea.

Effects of diagnostic uncertainty and misclassification on hospital performance indicators for acute stroke care.

The Stroke Improvement National Audit Programme (SINAP), now replaced by the Sentinel Stroke National Audit Programme, was established to provide comparative data on hospital performance indicators for stroke, but comparisons are only valid if case ascertainment is complete. In Gateshead we compared initial results from SINAP with those from a pre-existing hospital stroke register, which ran independently for 11 months after SINAP's introduction in 2010, as well as with Hospital Episode Statistics (HES) data. Of 315 confirmed acute stroke cases identified from the three combined data sources, 96 (30%) were omitted from SINAP and 51 (16%) were missed by HES. Of 478 suspected strokes in the combined datasets, 214 were either misclassified by HES or remained with uncertain diagnosis. These patients had much lower mortality and shorter hospital stays than those with confirmed stroke. This diagnostic uncertainty could be an important source of uncontrolled variation in, or even a potential target for manipulation of, hospital performance indicators for stroke.