Impact of stroke-associated pneumonia on mortality, length of hospitalization, and functional outcome

OBJECTIVES

Stroke-associated pneumonia (SAP) is common and associated with adverse outcomes. Data on its impact beyond 1 year are scarce.

MATERIALS AND METHODS

This observational study was conducted in a cohort of stroke patients admitted consecutively to a tertiary referral center in the east of England, UK (January 2003-April 2015). Logistic regression models examined inpatient mortality and length of stay (LOS). Cox regression models examined longer-term mortality at predefined time periods (0-90 days, 90 days-1 year, 1-3 years, and 3-10 years) for SAP. Effect of SAP on functional outcome at discharge was assessed using logistic regression.

RESULTS

A total of 9238 patients (mean age [±SD] 77.61 ± 11.88 years) were included. SAP was diagnosed in 1083 (11.7%) patients. The majority of these cases (n = 658; 60.8%) were aspiration pneumonia. After controlling for age, sex, stroke type, Oxfordshire Community Stroke Project (OCSP) classification, prestroke modified Rankin scale, comorbidities, and acute illness markers, mortality estimates remained significant at 3 time periods: inpatient (OR 5.87, 95%CI [4.97-6.93]), 0-90 days (2.17 [1.97-2.40]), and 91-365 days (HR 1.31 [1.03-1.67]). SAP was also associated with higher odds of long LOS (OR 1.93 [1.67-2.22]) and worse functional outcome (OR 7.17 [5.44-9.45]). In this cohort, SAP did not increase mortality risk beyond 1 year post-stroke, but it was associated with reduced mortality beyond 3 years.

CONCLUSIONS

Stroke-associated pneumonia is not associated with increased long-term mortality, but it is linked with increased mortality up to 1 year, prolonged LOS, and poor functional outcome on discharge. Targeted intervention strategies are required to improve outcomes of SAP patients who survive to hospital discharge.

Addition of sodium criterion to SOAR stroke score

OBJECTIVES

To examine the usefulness of including sodium (Na) levels as a criterion to the SOAR stroke score in predicting inpatient and 7-day mortality in stroke.

MATERIALS AND METHODS

Data from the Norfolk and Norwich University Hospital Stroke & TIA register (2003-2015) were analysed. Univariate and then multivariate models controlling for SOAR variables were used to assess the association between admission sodium levels and inpatient and 7-day mortality. The prognostic ability of the SOAR and SOAR Na scores for mortality outcomes at both time points were then compared using the Area Under the Curve (AUC) values from the Receiver Operating Characteristic curves.

RESULTS

A total of 8493 cases were included (male=47.4%, mean (SD) 77.7 (11.6) years). Compared with normonatremia (135-145 mmol/L), hypernatraemia (>145 mmol/L) was associated with inpatient mortality and moderate (125-129 mmol/L) and severe hypontraemia (<125 mmol/L) with 7-day mortality after adjustment for stroke type, Oxfordshire Community Stroke Project classification, age, prestroke modified Rankin score and sex. The SOAR and SOAR-Na scores both performed well in predicting inpatient mortality with AUC values of .794 (.78-.81) and .796 (.78-.81), respectively. 7-day mortality showed similar results. Both scores were less predictive in those with chronic kidney disease (CKD) and more so in those with hypoglycaemia.

CONCLUSION

The SOAR-Na did not perform considerably better than the SOAR stroke score. However, the performance of SOAR-Na in those with CKD and dysglycaemias requires further investigation.

Age but not ABCD(2) score predicts any level of carotid stenosis in either symptomatic or asymptomatic side in transient ischaemic attack

BACKGROUND

The ABCD(2) score is routinely used in assessment of transient ischaemic attack (TIA) to assess the risk of developing stroke. There remains uncertainty regarding whether the ABCD(2) score could be used to help predict extent of carotid artery stenosis (CAS).

OBJECTIVES

We aimed to (i) collate and analyse all available published literature on this topic and (ii) compare the data from our local population to the existing evidence base.

MATERIALS AND METHODS

We conducted a retrospective-observational study over a 6-month period using our East of England hospital-based TIA clinic data with a catchment population of ~750,000. We also searched the literature on studies reporting the association between ABCD(2) score and CAS.

RESULTS

We included 341 patients in our observational study. The mean age in our cohort was 72.86 years (SD 10.91) with 52% male participants. ABCD(2) score was not significantly associated with CAS (p = 0.78). Only age > 60 years was significantly associated with ipsilateral (> 50%) and contralateral CAS (> 50% and > 70%) (p < 0.01) after controlling for other confounders. The systematic review identified four studies for inclusion and no significant association between ABCD(2) score and CAS was reported, confirming our findings.

CONCLUSION

Our systematic review and observational study confirm that the ABCD(2) score does not predict CAS. However, our observational study has examined a larger number of possible predictors and demonstrates that age appears to be the single best predictor of CAS in patients presenting with a TIA. Selection of urgent carotid ultrasound scan thus should be based on individual patient's age and potential benefit of carotid intervention rather than ABCD(2) score.

The SOAR stroke score predicts hospital length of stay in acute stroke: an external validation study

AIMS

The objective of this study is to externally validate the SOAR stroke score (Stroke subtype, Oxfordshire Community Stroke Project Classification, Age and prestroke modified Rankin score) in predicting hospital length of stay (LOS) following an admission for acute stroke.

METHODS

We conducted a multi-centre observational study in eight National Health Service hospital trusts in the Anglia Stroke & Heart Clinical Network between September 2008 and April 2011. The usefulness of the SOAR stroke score in predicting hospital LOS in the acute settings was examined for all stroke and then stratified by discharge status (discharged alive or died during the admission).

RESULTS

A total of 3596 patients (mean age 77 years) with first-ever or recurrent stroke (92% ischaemic) were included. Increasing LOS was observed with increasing SOAR stroke score (p < 0.001 for both mean and median) and the SOAR stroke score of 0 had the shortest mean LOS (12 ± 20 days) while the SOAR stroke score of 6 had the longest mean LOS (26 ± 28 days). Among patients who were discharged alive, increasing SOAR stroke score had a significantly higher mean and median LOS (p < 0.001 for both mean and median) and the LOS peaked among patients with score value of 6 [mean (SD) 35 ± 31 days, median (IQR) 23 (14-48) days]. For patients who died as in-patient, there was no significant difference in mean or median LOS with increasing SOAR stroke score (p = 0.68 and p = 0.79, respectively).

CONCLUSION

This external validation study confirms the usefulness of the SOAR stroke score in predicting LOS in patients with acute stroke especially in those who are likely to survive to discharge. This provides a simple prognostic score useful for clinicians, patients and service providers.

TIA, stroke and orthostatic hypotension: a disease spectrum related to ageing vasculature?

AIMS

We sought to identify the determinants of orthostatic hypotension (OH) among patients referred to the transient ischaemic attack (TIA) clinic.

METHODS

We conducted a retrospective analysis of prospectively collected data on patients who attended the TIA clinic in a UK hospital between January 2006 and September 2009. Each patient had their supine and standing or sitting blood pressure measured. Logistic regression was used to estimate the univariate and multivariate odds of OH for the subgroups of patients based on their diagnosis. A 10% significance level for the univariate analysis was used to identify variables in the multivariate model.

RESULTS

A total of 3222 patients were studied of whom 1131 had a TIA, 665 a stroke and 1426 had other diagnoses. The prevalence of either systolic or diastolic OH in the TIA, stroke and patients with other diagnoses was similar being 22% (n = 251), 24% (n = 162) and 20% (n = 292), respectively. Multivariate analyses showed age, prior history of TIA, and diabetes were independently significantly associated with systolic OH alone or diastolic OH alone or either systolic or diastolic OH [ORs 1.03 (1.02-1.05); 1.56 (1.05-2.31); 1.65 (1.10-2.47), respectively]. Among the patients with the diagnosis of stroke, peripheral vascular disease (PVD) was significantly associated with increased odds of OH (3.56, 1.53-8.31), whereas male gender had a significantly lower odds of OH (0.61, 0.42-0.88). In patients with other diagnoses, age (1.04, 1.02-1.05) and diabetes (1.47, 1.04-2.09) were associated with OH, whereas male gender was (0.76, 0.58-1.00) not associated with OH.

CONCLUSION

Orthostatic hypotension is prevalent among patients presenting to TIA clinic. Previous history of vascular disease (prior TIA/stroke/PVD) appears to be a significant associate of OH in this patient population.

A systematic review of the pharmacological management of orthostatic hypotension

OBJECTIVES

The 'short' and 'long-term' benefits of pharmacological interventions to treat orthostatic hypotension (OH) remain unclear. The aim was to systematically examine the published literature on the effectiveness of different drug regimens for the treatment of OH.

DESIGN

Systematic review.

SETTING

MEDLINE (1950-Week 7, 2011), EMBASE (1980-Week 7, 2011), CINAHL (1981-Week 7, 2011) databases and hand-searching of bibliographies were used to identify suitable papers.

PARTICIPANTS

Studies selected were those, which investigated drug treatment of OH in a single- or double-blind randomised controlled trial (RCT) in humans over 18 years of age.

MEASUREMENTS

Data were extracted from suitable full-text articles by three investigators independently.

RESULTS

The 13 trials met the criteria for systematic review amongst which was considerable variation in the size of postural blood pressure (BP) change with active treatment. However, there was evidence that commonly used drugs midodrine or fludrocortisone therapy did increase standing or head-up-tilt (HUT) systolic blood pressure in certain patient groups.

CONCLUSION

The evidence that pharmacological therapy is of benefit for the treatment of OH is limited by the lack of good quality clinical trial evidence. Further well-designed RCTs of pharmacological treatment of OH investigating the impact on postural symptoms as well as actual BP changes are needed.

Predictors of early mortality among hospitalized nursing home residents

BACKGROUND

Emergency admissions from nursing homes (NHs) are associated with high mortality. Understanding the predictors of early mortality in these patients may guide clinicians in choosing appropriate site and level of care.

METHODS

We identified all consecutive admissions from NHs (all ages) to an Acute Medical Assessment Unit between January 2005 and December 2007. Analysis was performed at the level of the admission. The predictors of in-patient mortality at 7 days were examined using a generalized estimating equations analysis.

RESULTS

A total of 314 patients [32% male, mean age: 84.2 years (SD: 8.3 years)] were admitted during the study period constituting 410 emergency episodes. Twenty-three percent of admissions resulted in hospital mortality with 73% of deaths occurring within 1 week (50% within the first 3 days). For 7-day mortality outcome, patients with a modified early warning score (MEWS) of 4-5 on admission had 12 times the odds of death [95% confidence interval (CI) 1.40-103.56], whereas those with a score of ≥6 had 21 times the odds of death (95% CI 2.71-170.57) compared with those with a score of ≤1. An estimated glomerular filtration rate (eGFR) of 30-60 and <30 ml/min/m(2) was associated with nearly a 3-fold increase in the odds of death at 1 week (95% CI 1.10-7.97) and a 5-fold increase in the odds of death within 1 week (95% CI 1.75-14.96), respectively, compared with eGFR > 60 ml/min/m(2). C-reactive protein (CRP) >100 mg/l on admission was also associated with a 2.5 times higher odds of death (95% CI 1.23-4.95). Taking eight or more different medication items per day was associated with only a third of the odds of death (95% CI 0.09-0.98) compared with patients taking only three or fewer per day.

CONCLUSION

In acutely ill NH residents, MEWS is an important predictor of early hospital mortality and can be used in both the community and the hospital settings to identify patients whose death maybe predictable or unavoidable, thus allowing a more holistic approach to management with discussion with patient and relatives for planning of immediate care. In addition, CRP and eGFR levels on admission have also been shown to predict early hospital mortality in these patients and can be used in conjunction with MEWS in the same way to allow decision making on the appropriate level of care at the point of hospital admission.

Age, co-morbidity and poor mobility: no evidence of predicting in-patient death and acute hospital length of stay in the oldest old

BACKGROUND

The oldest old (aged over 90 years) are the fastest growing section of the UK population. Limited data exist regarding the effect of age, location, co-morbidity and physical performance status on outcome of acute illness in this age group.

METHODS

We performed a prospective study in people aged ≥ 90 years using hospital audit data in three hospitals in England and Scotland. We examined the characteristics of those admitted over three consecutive calendar months and calculated risk ratios of death and prolonged length of acute hospital stay (>7 days).

RESULTS

A total of 419 patients were included in this study (68% female, median age 93 years). There were similarities in presentation and diagnoses, but patients in Scotland (n = 164) were more likely to be admitted from sheltered housing or nursing homes than those in England (n = 255). Patients in England were significantly less likely to be able to mobilize < 10 m (41 vs. 34%, P < 0.001) but had lower prevalence of hypertension (40 vs. 55%, P = 0.02), ischaemic heart disease (30% vs. 45%, P = 0.02) and fewer prescribed medications (median 2 vs. 3, P < 0.001). Mortality was similar for the England and Scotland centres (P = 0.98). Previously recognized risk factors for death following hospital admission and length of stay e.g. older age, higher number of co-morbidities and poor mobility were not predictive in this study.

CONCLUSION

The 'oldest old' should not be considered as a homogenous group and findings from single-centre studies involving this age group may not be generalizable. We found no conclusive evidence that patient-related factors predict outcome in this age group in acute medical admission settings.

Drenching adult ewes: Implications of anthelmintic treatments pre- and post-lambing on the development of anthelmintic resistance

AIMS

To test the hypothesis that peri-parturient anthelmintic treatment of adult ewes, either pre-lambing with a controlled- release capsule (CRC) or at tail-docking with a short-acting oral formulation, would increase the rate of development of anthelmintic resistance, as compared to not drenching ewes and giving an additional drench to lambs in the autumn. Also, to evaluate the potential of routinely leaving 15% of the heaviest lambs untreated when drenching, as a means of slowing the development of anthelmintic resistance.

METHODS

A replicated farmlet trial was run from 1999- 2004. Eleven farmlets, each consisting of five paddocks, were initially seeded with Ostertagia (=Teladorsagia) circumcincta and Trichostrongylus colubriformis parasites, these being a mixture of albendazole-susceptible and -resistant isolates to yield a 96% reduction in faecal nematode egg count (FEC) on drenching. Four prescriptive drenching regimes were applied; Treatments 1-3 were replicated three times and Treatment 4 twice. Treatments were as follows. Treatment 1: Ewes were given an albendazole CRC pre-lambing, and any ewes exceeding 65 kg liveweight were given two capsules simultaneously; lambs were given a five-drench preventive programme of treatments, orally, of albendazole on Days 0, 21, 42, 70 and 98 after weaning. Treatment 2: Ewes were given a single oral treatment of albendazole at docking (2-3 weeks after lambing), and lambs were given the same five-drench preventive programme as in Treatment 1. Treatment 3: Ewes remained untreated, while lambs were given a six-drench preventive programme of treatments, orally, of albendazole on Days 0, 21, 42, 70, 98 and 126 after weaning. Treatment 4: Ewes remained untreated, while lambs were given the same six-drench preventive programme as in Treatment 3, but the heaviest 15% of lambs were left untreated each time. Albendazole-resistance status was measured at least twice-yearly, using faecal egg count reduction tests (FECRTs) and larval development assays (LDA). In addition, controlled slaughter of drenched and undrenched tracer lambs was undertaken in the last 3 years.

RESULTS

Resistance to albendazole increased most rapidly in Treatment 1, as measured by FECRT and LDA results, and worm burdens in tracer lambs. In Treatment 2, resistance developed slower than in Treatment 1 but faster than in Treatments 3 and 4, as measured by LDA; resistance in Treatment 2 developed more quickly than in Treatment 4, as measured by FECRTs. There was no significant difference between Treatments 3 and 4, although this approached significance in Ostertagia spp, as measured by LDA.

CONCLUSIONS

Anthelmintic treatments to adult ewes around lambing time are likely to be more selective for resistance than additional treatments administered to lambs in the autumn. Farmers wishing to slow the emergence of anthelmintic resistance on their farms should look to minimise the administration of peri-parturient treatment of ewes. A trend to slower development of resistance where a proportion of lambs were left untreated at each drench suggests further work on this aspect of management of resistance is warranted.

High mortality of older patients admitted to hospital from care homes and insight into potential interventions to reduce hospital admissions from care homes: the Norfolk experience

There is a high mortality rate in patients admitted to hospitals acutely from care homes. In a retrospective case analysis study of 3772 older people admitted to the Department of Medicine for the Elderly between January and June 2005, 340 (9.0%) were from care homes, and 93 (27.3%) of the residents died during the index admission. Nearly 40% of these deaths occurred within 24h of admission indicating a high level of less appropriate admissions. Investigating eight nursing homes which admitted the highest number of patients from one primary care trust revealed that the most cited reasons for admission were the lack of advance care plans, access to General Practitioners (GPs) out of hours, as well as general access to palliative care and specialist nurses, and poor communication between patient, relatives, GPs, hospitals and care home staff. Our findings provide some useful insight into the factors that need to be addressed to avoid unnecessary or inappropriate admissions from care homes for better end of life care in aging societies.

Continuous estimates of dynamic cerebral autoregulation: influence of non-invasive arterial blood pressure measurements

Temporal variability of parameters which describe dynamic cerebral autoregulation (CA), usually quantified by the short-term relationship between arterial blood pressure (BP) and cerebral blood flow velocity (CBFV), could result from continuous adjustments in physiological regulatory mechanisms or could be the result of artefacts in methods of measurement, such as the use of non-invasive measurements of BP in the finger. In 27 subjects (61+/-11 years old) undergoing coronary artery angioplasty, BP was continuously recorded at rest with the Finapres device and in the ascending aorta (Millar catheter, BP(AO)), together with bilateral transcranial Doppler ultrasound in the middle cerebral artery, surface ECG and transcutaneous CO(2). Dynamic CA was expressed by the autoregulation index (ARI), ranging from 0 (absence of CA) to 9 (best CA). Time-varying, continuous estimates of ARI (ARI(t)) were obtained with an autoregressive moving-average (ARMA) model applied to a 60 s sliding data window. No significant differences were observed in the accuracy and precision of ARI(t) between estimates derived from the Finapres and BP(AO). Highly significant correlations were obtained between ARI(t) estimates from the right and left middle cerebral artery (MCA) (Finapres r=0.60+/-0.20; BP(AO) r=0.56+/-0.22) and also between the ARI(t) estimates from the Finapres and BP(AO) (right MCA r=0.70+/-0.22; left MCA r=0.74+/-0.22). Surrogate data showed that ARI(t) was highly sensitive to the presence of noise in the CBFV signal, with both the bias and dispersion of estimates increasing for lower values of ARI(t). This effect could explain the sudden drops of ARI(t) to zero as reported previously. Simulated sudden changes in ARI(t) can be detected by the Finapres, but the bias and variability of estimates also increase for lower values of ARI. In summary, the Finapres does not distort time-varying estimates of dynamic CA obtained with a sliding window combined with an ARMA model, but further research is needed to confirm these findings in healthy subjects and to assess the influence of different physiological manoeuvres.

Cerebral critical closing pressure estimation from Finapres and arterial blood pressure measurements in the aorta

Estimates of cerebral critical closing pressure (CrCP) and resistance-area product (RAP) are often derived using noninvasive measurements of arterial blood pressure (ABP) in the finger, but the errors introduced by this approach, in relation to intra-vascular measurements of ABP, are not known. Continuous recordings of ABP (Finapres and solid-state catheter-tip transducer in the ascending aorta), cerebral blood flow velocity (CBFV, bilateral Doppler), ECG and transcutaneous CO(2) were performed following coronary catheterization. CrCP and RAP were calculated for each of 12,784 cardiac cycles from 27 subjects using the classical linear regression (LR) of the instantaneous CBFV-ABP relationship and also the first harmonic (H(1)) of the Fourier transform. There was a better agreement between LR and H(1) for the aortic measurements than for the Finapres (p < 0.000,01). For LR there were no significant differences for either CrCP or RAP due to the source of ABP measurement, but for H(1) the differences were highly significant (p < 0.000,03). The coherence functions between either CrCP or RAP values calculated with aortic pressure (input) or the Finapres (output) were significantly higher for H(1) than for LR for most harmonics below 0.2 Hz. When using the Finapres to estimate CrCP and RAP values, the LR method produces similar results to intra-arterial measurements of ABP for time-averaged values, but H(1) should be preferred in applications analysing beat-to-beat changes in these parameters.

A study of statin use in the prevention of cognitive impairment of vascular origin in the UK

INTRODUCTION

There is increasing evidence suggesting that control of hypertension and antiplatelet therapy may prevent or reduce progression of vascular-related cognitive impairment (VCI), though a similar role of statins in this group of patients has yet to be established.

METHODS

We conducted a postal survey of a group of 296 medical practitioners (comprising of physicians and psychiatrists specialising in the elderly, and general practitioners) inquiring into their management of (a) patients at high risk of developing VCI and (b) patients with established VCI.

RESULTS

The overall response rate was 60% (177/296), with the highest response rate from psychiatrists. (a) For patients at high risk of developing VCI: 47% of clinicians believed that statins had an important role in preventing subsequent dementia: 4% would commence statins at a total cholesterol (TC) of 4-5 mmol/L; 38% with a TC of 5.1-6.5 mmol/L; and 32% with a TC of 6.6-8 mmol/L. Cardiovascular risk profile, age, cost and gender were other factors considered as important factors influencing statin prescription. (b) In those patients with established VCI: 32% of clinicians felt that statins had an important role in arresting progression, usually in people with a mild degree of cognitive impairment: 4% would commence statins at a TC of 4-5 mmol/L; 25% with a TC of 5.1-6.5 mmol/L; and 22% with a TC of 6.6-8 mmol/L. There were no major differences between clinicians in their prescribing habits.

CONCLUSIONS

A substantial proportion of clinicians favour the use of statins in primary and secondary prevention of cognitive impairment of vascular origin, despite a lack of definite evidence to support their use at the present time.

Variability of time-domain indices of dynamic cerebral autoregulation

The intra- and inter-subject variabilities of the cerebral dynamic autoregulatory index (ARI) were studied in a group of 14 healthy subjects aged 23-51 years. An alternative index, derived from autoregressive-moving average (ARMA) modelling of the arterial blood pressure (ABP)-cerebral blood flow velocity (CBFV) dynamic relationship, named ARMA-ARI, is also proposed. The susceptibility of both indices to physiological sources of variability was studied by performing measurements during spontaneous respiration (SR), and controlled breathing at 6, 10 and 15 breaths min(-1). ABP was measured non-invasively (Finapres), CBFV was recorded with Doppler ultrasound in both middle cerebral arteries and end-tidal CO2 (EtCO2) was estimated with an infrared capnograph. ARI and ARMA-ARI were calculated as a summary measure for the whole of each recording period, and also continuously, using a 60 s moving data window. Respiration did not have an effect on either of these indices, despite significant, but relatively small, reductions in EtCO2 at 10 and 15 bpm, compared to SR. Very significant differences were observed between ARI and ARMA-ARI in relation to their stability, variability and sensitivity to discriminate between subjects. For continuous estimates the coefficient of variation of ARI was 30 +/- 21% compared to 15 +/- 8% for ARMA-ARI (p < 0.000). The cumulative probability distributions were also significantly different for the two indices for each of the respiratory manoeuvres. The greater stability and reduced variability of ARMA-ARI, in relation to the classic ARI, suggest that the former should be used in future studies of dynamic autoregulation, mainly in situations where an improved temporal resolution might be required, such as the investigation of vaso-vagal syncope or the physiology of exercise.

Continuous cardiac baroreceptor measurement during tilt in healthy elderly subjects

INTRODUCTION

Abnormalities of cardiac baroreceptor sensitivity (BRS) may contribute towards the high prevalence of orthostatic hypotension and falls in the elderly. Most mathematical analyses used to determine BRS in the time or frequency domains assume a stationary physiological state and cannot be performed under dynamic change and therefore are not valid during tilt. We describe a new method of estimating BRS during tilt.

METHODS

Twenty-five healthy elderly volunteers with a mean age of 69 +/- 3 years underwent head-up tilt to 70 degrees, within 5 s, 3 times on 2 separate visits. Blood pressure (BP) and heart rate were recorded continuously using a Finapres beat-to-beat BP monitor and surface ECG. A continuous estimate of BRS was obtained by combining beat-to-beat linear regression with Legendre polynomial interpolation.

RESULTS

The values for supine BRS prior to tilt on the two visits, calculated using the new regression method (10.4 +/- 8.2 ms/mmHg and 12.5 +/- 9.7 ms/mmHg) were similar to those using fast Fourier analysis (10.7 +/- 6.7 ms/mmHg and 12.4 +/- 7.1 ms/mmHg). A rapid fall in BP and pulse interval along with cardiac BRS values occurred with tilt within the first 20 s of onset on both visits and remained reduced up to 90 s post tilt (p < 0.01).

CONCLUSIONS

The values for cardiac BRS obtained using continuous time domain analysis agree well with those calculated using spectral methods and can be used to assess the dynamic changes in BRS to rapid perturbations in BP such as that occur with tilt.

Dynamic cerebral autoregulation and beat to beat blood pressure control are impaired in acute ischaemic stroke

OBJECTIVES

Hypertension and chronic cerebrovascular disease are known to alter static cerebral autoregulation (CA) but the effects of acute stroke on dynamic CA (dCA) have not been studied in detail. Those studies to date measuring dCA have used sympathetically induced blood pressure (BP) changes, which may themselves directly affect dCA. This study assessed whether dCA is compromised after acute stroke using spontaneous blood pressure (BP) changes as the stimulus for the dCA response.

METHODS

56 patients with ischaemic stroke (aged 70 (SD 9) years), studied within 72 hours of ictus were compared with 56 age, sex, and BP matched normal controls. Cerebral blood flow velocity was measured using transcranial Doppler ultrasound (TCD) with non-invasive beat to beat arterial BP levels, surface ECG, and transcutaneous CO(2) levels and a dynamic autoregulatory index (dARI) calculated.

RESULTS

Beat to beat BP, but not pulse interval variability was significantly increased and cardiac baroreceptor sensitivity (BRS) decreased in the patients with stroke. Dynamic CA was significantly reduced in patients with stroke compared with controls (strokes: ARI 3.8 (SD 2.2) and 3.2 (SD 2.0) for pressor and depressor stimuli respectively v controls: ARI 4.7 (SD 2.2) and 4.5 (SD 2.0) respectively (p<0.05 in all cases)). There was no difference between stroke and non-stroke hemispheres in ARI, which was also independent of severity of stroke, BP, BP variability, BRS, sex, and age.

CONCLUSION

Dynamic cerebral autoregulation, as assessed using spontaneous transient pressor and depressor BP stimuli, is globally impaired after acute ischaemic stroke and may prove to be an important factor in predicting outcome.

Interventions in the management of serum lipids for preventing stroke recurrence

BACKGROUND

A close association between serum lipid levels and the incidence of coronary heart disease (CHD) has been well proven in middle aged and older persons, up to the age of 70-75 years. Individual studies have shown interventions to reduce total and low density lipoprotein (LDL) cholesterol levels, especially with 3-hydroxy-3-methylglutaryl coenzyme a (HMG-CoA) reductase inhibitors (statins), to be of benefit in reducing CHD and stroke events in those with a history of coronary heart disease. However, the relation of serum cholesterol and cholesterol sub-fractions with cerebrovascular disease is less clear. It is unclear whether lipid levels in the post-stroke period are a predictor of recurrence and whether treatment to alter levels can prevent recurrence of either stroke or cardiovascular events.

OBJECTIVES

To investigate the effect of altering serum lipids in the prevention of cardiovascular disease and stroke recurrence in subjects with a history of stroke.

SEARCH STRATEGY

The Cochrane Group Trials Register was searched up to 8 May 2001 along with MEDLINE (from 1966), EMBASE (from 1980) and the Cochrane Controlled Trials Register. All pharmaceutical firms known to produce a lipid lowering agent were also contacted and asked to provide information on publications or unpublished work relevant to this review.

SELECTION CRITERIA

This review included unconfounded randomised trials of subjects aged 18 years and over with a history of stroke or Transient Ischaemic Attack (TIA).

DATA COLLECTION AND ANALYSIS

The data were extracted independently by the three reviewers. MetaView 4.1 was used for all statistical analyses.

MAIN RESULTS

Five studies involving 1700 patients were included in the review. The active intervention in two of the studies was Clofibrate, Pravastatin in another two and Conjugated Oestrogen in the fifth. Fixed effects analysis showed no evidence of a difference in stroke recurrence between the treatment and placebo groups for those with a previous history of stroke or TIA (odds ratio 0.96, 95% confidence interval 0.71 to 1.30). In addition there was also no evidence, based on two studies, that intervention reduced the odds of all cause mortality (odds ratio 0.87, 95% confidence interval 0.55 to 1.39) nor, from one study, that there was any effect on subsequent vascular events (odds ratio 1.27, 95% confidence interval 0.84 to 1.89).

REVIEWER'S CONCLUSIONS

These trials do not provide evidence for a benefit, or harm, from interventions to alter serum lipid levels in patients with a history solely of cerebrovascular disease. Their use, therefore, cannot yet be recommended routinely in this patient group, but ischaemic stroke patients with a history of myocardial infarction should receive statin therapy along the lines of the previous recommendations for those patients with a history of myocardial ischaemia. There are currently three ongoing trials which will recruit approximately 30,000 patients, including those with a history of stroke, and the results of these trials may have a significant effect on these conclusions.

Twenty-four hour systolic blood pressure predicts long-term mortality following acute stroke

OBJECTIVE

To assess the effects of acute blood pressure (BP) on long-term mortality following stroke.

DESIGN

Prospective observational study.

SETTING

Leicester Teaching Hospitals.

PATIENTS

Two hundred and nineteen consecutive patients were recruited within 24 h of acute stroke.

INTERVENTIONS

Clinic and 24 h BP levels were measured. Other risk factors previously associated with stroke mortality were recorded within 24 h of admission. No specific pharmacological interventions;were made.

MAIN OUTCOME MEASURES

The primary outcome measure was death over a median follow-up period of over 2.5 years. The hazards ratios associated with predefined variables were assessed using Cox's proportional hazards modelling, and Kaplan-Meier survival plots were also calculated.

RESULTS

On multiple variable analysis, 24 h systolic BP (> or = 160 mmHg) was associated with an increased hazards ratio of 2.41 (95% confidence intervals: 1.24-4.67) for death, compared to the reference group (140-159 mmHg). The addition of 24 h heart rate was significant, with increasing heart rate (> 83 bpm) associated with an increased mortality (P = 0.006), although this effect was not constant over time. Increasing age (> 80 years) at presentation was also associated with an increased hazards ratio of 2.53 (1.14-5.62) compared to age < or = 66 years.

CONCLUSIONS

This study provides evidence that elevated 24 h systolic BP in the acute stroke period is associated with increased long-term mortality. This may have implications in the therapeutic management of BP following stroke, though further research is required to determine the timing, nature and effect of such an intervention.

Carbon dioxide, critical closing pressure and cerebral haemodynamics prior to vasovagal syncope in humans

The cerebrovascular changes that occur prior to vasovagal syncope (VVS) are unclear, with both increases and decreases in cerebrovascular resistance being reported during pre-syncope. This study assessed the cerebrovascular responses, and their potential underlying mechanisms, that occurred before VVS induced by head-up tilt (HUT). Groups of 65 normal subjects with no previous history of syncope and of 16 patients with recurrent VVS were subjected to 70 degrees HUT for up to 30 min. Bilateral middle cerebral artery (MCA) cerebral blood flow velocities (CBFVs) were measured using transcranial Doppler ultrasound, along with simultaneous measures of MCA blood pressure, heart rate, and end-tidal and transcutaneous carbon dioxide concentrations. All 16 patients and 14 of the control subjects developed VVS during HUT. During pre-syncope, mean CBFV declined, due predominantly to a decrease in diastolic rather than systolic CBFV (decreases of 44.5+/-19.8% and 6.3+/-12.9% respectively; P<0.0001). CO(2) levels and indices of cerebrovascular resistance decreased during pre-syncope, while critical closing pressure (CrCP) increased to levels approaching MCA diastolic blood pressure before decreasing precipitously on syncope. Pre-syncopal changes were similar in syncopal patients and syncopal controls. CrCP, therefore, rises during pre-syncope, possibly related to progressive hypocapnia, and may account for the relatively greater fall in diastolic CBFV. Falls in cerebrovascular resistance, therefore, may be offset by rises in CrCP due to hypocapnia, leading to diminished cerebral blood flow during pre-syncope.

Cerebral autoregulatory responses to head-up tilt in normal subjects and patients with recurrent vasovagal syncope

BACKGROUND

The effect of orthostatic stress on dynamic cerebral autoregulation (CA) in normal subjects and patients with recurrent vasovagal syncope (VVS) is unclear. This study assessed the dynamic CA responses of both groups to head-up tilt.

METHODS AND RESULTS

Seventeen patients with recurrent VVS and 17 pair-matched control subjects underwent 70 degrees head-up tilt for up to 30 minutes. Bilateral middle cerebral artery blood flow velocities (CBFV) were measured with transcranial Doppler ultrasound along with noninvasive beat-to-beat blood pressure (BP), heart rate, and transcutaneous and end-tidal CO(2) concentrations. Indices of dynamic CA were derived for periods before, during, and after tilt. Eight normal subjects who developed VVS in an identical protocol but who had no previous clinical history of syncope were also studied. CBFV and transcutaneous and end-tidal CO(2) levels declined significantly during head-up tilt in all groups (P<0.0001). Dynamic CA indices were unchanged throughout tilt in nonsyncopal control subjects and were initially unchanged in patients but deteriorated significantly in patients and syncopal control subjects in the minutes before (P=0.027 and P=0.012, respectively) and after (P=0.002 and P=0.007, respectively) syncope.

CONCLUSIONS

Dynamic CA is preserved in patients and control subjects initially after head-up tilt. Autoregulatory function remains intact in nonsyncopal control subjects during prolonged orthostasis but deteriorates in patients and syncopal control subjects immediately before and after VVS.

Cerebral blood flow velocity response to induced and spontaneous sudden changes in arterial blood pressure

The influence of different types of maneuvers that can induce sudden changes of arterial blood pressure (ABP) on the cerebral blood flow velocity (CBFV) response was studied in 56 normal subjects (mean age 62 yr, range 23-80). ABP was recorded in the finger with a Finapres device, and bilateral recordings of CBFV were performed with Doppler ultrasound of the middle cerebral arteries. Recordings were performed at rest (baseline) and during the thigh cuff test, lower body negative pressure, cold pressor test, hand grip, and Valsalva maneuver. From baseline recordings, positive and negative spontaneous transients were also selected. Stability of PCO2 was monitored with transcutaneous measurements. Dynamic autoregulatory index (ARI), impulse, and step responses were obtained for 1-min segments of data for the eight conditions by fitting a mathematical model to the ABP-CBFV baseline and transient data (Aaslid's model) and by the Wiener-Laguerre moving-average method. Impulse responses were similar for the right- and left-side recordings, and their temporal pattern was not influenced by type of maneuver. Step responses showed a sudden rise at time 0 and then started to fall back to their original level, indicating an active autoregulation. ARI was also independent of the type of maneuver, giving an overall mean of 4.7 +/- 2.9 (n = 602 recordings). Amplitudes of the impulse and step responses, however, were significantly influenced by type of maneuver and were highly correlated with the resistance-area product before the sudden change in ABP (r = -0.93, P < 0.0004). These results suggest that amplitude of the CBFV step response is sensitive to the point of operation of the instantaneous ABP-CBFV relationship, which can be shifted by different maneuvers. Various degrees of sympathetic nervous system activation resulting from different ABP-stimulating maneuvers were not reflected by CBFV dynamic autoregulatory responses within the physiological range of ABP.

The effect of systemic blood pressure on cardio-vascular reflexes in elderly subjects

The evidence for impairment of cardiovascular reflexes by hypertension in elderly subjects is mixed. This study tested the hypothesis that baroreceptor- and non-baroreceptor-mediated responses in elderly subjects differed with hypertension. 54 elderly subjects were studied: 16 with combined hypertension (CT) (blood pressure 184 +/- 4/102 +/- 2 mmHg), 16 with isolated systolic hypertension (180 +/- 3/85 +/- 1 mmHg) and 22 normotensives (NT) (138 +/- 2/76 +/- 1 mmHg). All subjects performed isometric exercise with a handgrip dynamometer. Heart rate (HR), blood pressure and forearm vascular resistance (FVR) responses were then studied to 60 degrees head-up tilt and the cold face stimulus. Baseline FVR, and the response to isometric handgrip, were similar in all groups. Subjects with isolated systolic hypertension manifested greater increases in FVR with tilt (P<0.001), whilst the HR increment was greater in the NT group (P<0.001). Blood pressure changes with tilt were similar in the three groups. With the cold face stimulus (CFS) a rise in FVR of approximately 30% was seen in all groups and blood pressure rose modestly, with the largest increases being seen in the combined hypertensives. This study in elderly subjects indicates significant differences with hypertension in the response to tilt, with an impaired baroreceptor-cardiac reflex being compensated by an augmented baroreceptor-vascular response.

Barriers to vision care for nursing home residents

OBJECTIVE

To describe the prevalence of periodic eye examinations by eye professionals and to examine nursing facility resident characteristics associated with lack of periodic screening.

DESIGN

Retrospective chart review.

SETTING

Two Midwestern nursing facilities.

PARTICIPANTS

Between 1995 and 1997, 134 subjects aged 60 and older were recruited from two metropolitan nursing facilities.

MEASUREMENTS

Nursing home charts were reviewed for: demographics, length of stay, date of eye examination, eye diagnosis,visual acuity. Nursing assessments were used to obtain information about cognition, function, behavior, and the presence of Do Not Resuscitate or Do Not Hospitalize orders. The chart was reviewed for visual acuity, intraocular pressures, and the presence of eye pathology. Individuals who had not had eye examinations in the previous 2 years were screened by an ophthalmologist. This examination included external examination of the eye, fundoscopic examination, tonometry,visual acuity with correction.

RESULTS

Only 62 (46%) of the subjects had been seen by an eye care professional in the previous 2 years. Visual acuity information was available for 37/64 previously examined subjects. Of those with no eye examination in the previous 2 years (n = 72), visual acuity was obtained in 32 (44%) of subjects. New eye diagnoses were made in 64% (41/64). Logistic regression models with "eye examination within the past 2 years" as the dependent variable show that residents who do not desire hospital transfer are 80% less likely to have had an eye examination than those without this designation. Sex, age, length of stay, functional status, presence of severe dementia, behavior problems, or DNR orders do not change the likelihood that a resident would have been examined. Logistic regression models with "visual acuity measured" as the dependent variable show that residents with severe dementia are 12.6 times less likely to have acuity measured than those without dementia. Those with a length of stay in the facility less than 6 months are 10% less likely to have visual acuity measured.

CONCLUSIONS

This study does not confirm that barriers still exist in the provision of eye care to all nursing home residents, but the prevalence of such assessments remains low. Additional screening results in a substantial increase in the identification of treatable eye diseases. Contrary to the original hypotheses that patient characteristics that make testing difficult would provide a barrier or disincentive to vision testing, this study did not show statistical differences in the rates of vision screening for those with dementia, behavior problems, or severe functional impairment. Severe dementia does seem to affect the ability of the eye care specialist to gather subjective data such as visual acuity. It also demonstrates that vision screening does take place on nursing home residents with a broad range of cognitive and functional abilities, and this screening results in the diagnosis of many treatable eye conditions. Future efforts should be made to increase vision screening and treatment in the nursing home.

Dynamic cerebral autoregulation is unaffected by aging

BACKGROUND AND PURPOSE

Normal aging is associated with marked changes in the cardiovascular and cerebrovascular systems. Although cerebral autoregulation (CA) is impaired in certain disease states, the effect of age per se on dynamic CA in humans is unknown and the focus of this study.

METHODS

Twenty-seven young subjects (</=40 years) and 27 older subjects (>/=55 years), matched for sex and systolic blood pressure (BP), underwent measurement of cerebral blood flow velocity by transcranial Doppler ultrasound and noninvasive beat-to-beat arterial BP measurement during induced and spontaneous dynamic BP stimuli. A standard dynamic autoregulatory index (ARI) was derived for each spontaneous and induced dynamic BP stimulus to include the step response, as well as cardiac baroreceptor sensitivity (BRS), for the 2 groups.

RESULTS

The mean age of the young group was 29+/-5 years, and that of the older group was 68+/-5 years. Cardiac BRS was reduced in the older group (8. 6+/-4.5 versus 16.9+/-8.8 ms/mm Hg; P:<0.0001). However, no age-related differences were demonstrated in step response plots or in ARI values for any pressor or depressor dynamic BP stimulus (P:=0. 62), with mean ARI values for all stimuli combined being 4.9+/-1.8 for the young group and 5.0+/-2.3 for the older group.

CONCLUSIONS

Although increasing age is associated with a decrease in cardiac BRS, dynamic CA, as assessed by step response analysis as well as cerebral blood flow responses to transient and induced BP stimuli, is unaffected by aging.

A case of arrhythmia-induced transient cerebral hyperaemia

Transient cerebral hyperaemia following an arrhythmia has not been previously demonstrated in humans. We report the effects of head-up tilt on a 78-year-old man with neurocardiogenic syncope. During tilt, an asymptomatic arrhythmia caused arterial blood pressure and transcranial Doppler-recorded cerebral blood flow velocity to fall markedly. Upon spontaneous resumption of sinus rhythm, cerebral blood flow velocity increased to values greater than those prior to the arrhythmia. This occurred prior to a full recovery of arterial blood pressure, indicating spontaneous transisent hyperaemia. Pressure-flow velocity graphs support current methods of measuring critical closing pressure and demonstrate a rise in critical closing and a fall in resistance-area product after the arrhythmia.

Prevalence and impact of urinary symptoms among community-dwelling stroke survivors

BACKGROUND AND PURPOSE

To establish prevalence of urinary symptoms among community-dwelling stroke survivors and how these symptoms affected lives of these survivors compared with a nonstroke population.

METHODS

The present study was a community-based postal survey in Leicestershire community, UK (that excluded institutional settings), that was designed to track stroke, urinary, and bowel symptoms and the effect of such symptoms on relationships, social life, daily activities, and overall quality of life. Subjects included 14 600 people who were living in the community and </=40 years of age, randomly selected from the Leicestershire Health Authority Register.

RESULTS

A 70% response rate was achieved with the return of 10 226 questionnaires. Prevalence of reported stroke was 4% (n=423). Prevalence of urinary symptoms was 34% (n=3197). Overall, stroke survivors had a higher prevalence of symptoms than the nonstroke population (64% to 32%, respectively). These symptoms were reported to have more of an effect on the lives of the stroke survivors compared with the nonstroke population even when adjusted for age and sex differences. This reported impact was not related to the stroke per se but to the severity of the urinary symptoms.

CONCLUSIONS

These data show a high prevalence of urinary symptoms among community-dwelling stroke survivors. These symptoms were reported to have considerable impact on the lives of stroke survivors, which needs to be taken into account in future research and clinical practice.

The prevalence, composition, and function of ethics committees in nursing facilities: results of a random, national survey of American Health Care Association members

OBJECTIVES

To determine the prevalence, composition, and function of ethics committees in extended care facilities in the United States.

DESIGN

Descriptive survey by mail.

SETTING

A 5% random sample (n = 851) of nursing facility members of the American Health Care Association (n = 17,020). Most of these facilities (75%) are intermediate care facilities; the remainder include a varying number of skilled beds.

METHODS

An eight-item questionnaire was sent to the randomly selected 851 extended care facilities. The questionnaire inquired about the existence of an ethics committee, plans for formation when applicable, composition of the ethics committee, and its function. Survey data was coded and merged with information on facility characteristics that are part of the American Health Care Association's database.

RESULTS

Of the responding facilities (n = 394), 34% reported the presence of a functioning ethics committee, with an additional 19% indicating definite plans for ethic committee formation. Forty-three percent expressed no interest in establishing an ethics committee, and 4% reported having had an ethics committee sometime in the past. The greatest proportion of committee time was spent in case review (39%) with lesser amounts of time expended in areas of policy formation (27%) and education (27%). Forty percent of the ethics committees performed two or fewer case reviews per year. Nearly all committees included the following disciplines in the membership: nurses (96%), physicians (95%), and social workers (89%). Facility administrators (77%) and clergy (70%) were frequently represented. Very few facilities reported representation by residents (8%) and Certified Nursing Assistants (2%). The Medical Director served as a committee member on 75% of the ethics committees, and in more than one-half of those instances, he/she was the sole physician on the committee.

CONCLUSION

Ethics committees are currently active in or there are plans for their development in more than 50% of extended care facilities in the U.S. this represents a very significant increase in prevalence during the last decade. This tendency to form ethics committee's may slow considerably in the future. Ethics committees exhibit considerable variability in structure and function.

Dynamic but not static cerebral autoregulation is impaired in acute ischaemic stroke

It remains unclear as to whether dynamic and static cerebral autoregulation (CA) are impaired in acute ischaemic stroke, and whether these changes are related to stroke subtype. This could have important implications with regard to post-stroke prognosis and the management of blood pressure (BP) in the acute post-ictal period. Using transcranial Doppler ultrasonography and non-invasive manipulation of BP, we compared both mechanisms in 61 patients with ischaemic stroke within 96 h of ictus, and 54 age- and sex-matched controls. There was no difference in static and dynamic CA indices between the various stroke subtypes. Combining all stroke subtypes dynamic autoregulation, as measured using thigh cuff release, was significantly impaired in both the affected and non-affected stroke hemispheres compared to controls (mean autoregulation index 4.1 +/- 3.3, 4.8 +/- 3.1 and 6.2 +/- 2.3, respectively, p < 0.05). By comparison static autoregulation, assessed using isometric hand grip and thigh cuff inflation, was not significantly different. In conclusion, dynamic but not static CA appears to be globally impaired in acute ischaemic stroke. This deserves further study and may identify possibilities for therapeutic intervention.

Changes in baroreceptor sensitivity for heart rate during normotensive pregnancy and the puerperium

Normal pregnancy is associated with marked changes in cardiovascular haemodynamics, which in part may be due to changes in autonomic control mechanisms. Baroreflex sensitivity for heart rate (BRS) was calculated in the supine and standing positions using power spectral analysis of pulse interval (PI) and systolic blood pressure (SBP) in 16 normotensive pregnant women and 10 normotensive non-pregnant controls. The pregnant women were studied on three occasions during their pregnancy (early, mid- and late gestation) and once during the puerperium. Supine total SBP variability increased between early and late pregnancy by 79% [95% confidence intervals (CI) 30%, 145%; P<0. 001], and supine high-frequency PI variability decreased by 75% (CI 51%, 88%; P<0.001). Supine BRS fell by 50% (P<0.001), with values returning to early-pregnancy levels in the puerperium, which were similar to those recorded in the control group. Standing SBP variability and BRS values were unchanged during pregnancy and post partum. The low/high frequency ratio of PI variability, taken as a surrogate measure of sympathovagal balance, increased by 137% (CI 42%, 296%; P<0.01) in the supine but not the standing position from early to late pregnancy. This was due to a decrease in high-frequency variability rather than to an increase in low-frequency variability, suggesting that these changes may have been due to vagal withdrawal rather than increased sympathetic activity. Normotensive pregnancy is associated with a marked decrease in supine BRS, although the exact mechanisms for these changes remain unclear. Further studies are required to define whether changes in BRS and sympathovagal tone in early pregnancy can be used to predict the onset of pregnancy-induced hypertension.

Which parameters of beat-to-beat blood pressure and variability best predict early outcome after acute ischemic stroke?

BACKGROUND AND PURPOSE

In hypertensive populations, increasing blood pressure (BP) levels and BP variability (BPV) are associated with a greater incidence of target organ damage. After stroke, elevated 24-hour BP levels predict a poor outcome, although it is uncertain whether shorter-length BP recordings assessing mean BP levels and BPV have a similar predictive role. The objectives of this study were to compare the different measures of beat-to-beat BP and BPV on outcome after acute ischemic stroke and assess whether these parameters were affected by stroke subtype.

METHODS

Ninety-two consecutive admissions with a CT-confirmed diagnosis of acute ischemic stroke were recruited, of whom 54 had cortical infarction, 29 subcortical, and 9 posterior circulation infarction. Casual and two 5-minute recordings of beat-to-beat BP (Finapres, Ohmeda) were made under standardized conditions within 72 hours of ictus, with mean BP levels taken as the average of this 10-minute recording and BPV as the standard deviation. Outcome was assessed at 30 days as dead/dependent or independent (Rankin </=2). The effects of BP, BPV, and stroke subtype on outcome were studied with the use of logistic regression. Stroke subjects were subsequently divided by BP quartiles and within each quartile into low- and high-variability groups; the influence of high BPV on outcome was also assessed.

RESULTS

The odds ratio for death/dependency was significantly higher in cortical strokes compared with subcortical and posterior circulation strokes even after controlling for differences in BP and BPV (OR 4.19, P=0.002). Beat-to-beat systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP +/- SD) levels were higher in the dead/dependent group compared with the independent group (MAP 106+/-20.4 mm Hg vs 97+/-19.1 mm Hg, P<0.02), as was MAP variability: 6.1 (interquartile range 4.5 to 7.4 mm Hg) versus 4.9 (3.8 to 6.4 mm Hg, P=0.02). The odds ratio for a poor outcome was 1. 38 (P=0.014) for every 10-mm Hg increase in MAP and 1.32 (P=0.02) for every 1-mm Hg increase in MAP variability. Casual BP measurements had no prognostic significance. For the group as a whole when separated into BP quartiles, those with a high MAP and DBP but not SBP variability within each quartile had a worse prognosis compared with those with a low BPV.

CONCLUSIONS

A poor outcome at 30 days after ischemic stroke was dependent on stroke subtype, beat-to-beat DBP, and MAP levels and variability. Important prognostic information can be readily obtained from a short period of noninvasive BP monitoring in the acute stroke patient. These findings have important implications, particularly regarding the use of hypotensive agents in the acute stroke period.

The effect of visual and hearing impairments on functional status

OBJECTIVES

To describe the prevalence of visual and auditory impairment in frail older persons and to evaluate the association between sensory impairment and overall functional status.

DESIGN

Prospective patient evaluation and retrospective analysis of data.

SETTING

The outpatient geriatric assessment clinic of a university medical center.

PARTICIPANTS

Consecutive patients seen in the University of Nebraska Medical Center Outpatient Geriatric Assessment Clinic from 1986 to 1992 for whom both vision and hearing information were available (n = 576).

MEASUREMENTS

Visual acuity was measured by the Lighthouse Near Visual Acuity Test, and auditory acuity was evaluated with the whisper test. Functional status was determined by Lawton-Brody activities of daily living (ADL) and instrumental activities of daily living (IADL) scales. Comorbid illness was classified by the Cumulative Illness Rating Scale, and mental status was assessed by the Folstein Mini-Mental State Exam.

RESULTS

Eighteen percent of patients had visual impairment of 20/70 or worse. Hearing impairment was found in 64%. The mean ADL and IADL scores were 20/24 and 12/23, respectively, for patients with visual acuity better than 20/70, compared with 18/24 and 8/23 for visually impaired patients (P < .001 for both comparisons). ADL and IADL scores were also higher in hearing intact patients compared with those with hearing impairment: respectively, 21/24 vs 19/24 (P < .001) and 13/23 vs 11/23 (P < .001). The effects of visual acuity and hearing acuity on IADL score are independent of mental status and comorbid illness (P < .001). The effect of visual acuity on ADL score is independent of mental status and comorbid illness (P < .001), whereas the effect of hearing on ADL score is not. Subjects with both hearing and vision impairment had mean IADL (P < = .05) and ADL (P < = .05) scores significantly lower than those with no impairment

CONCLUSIONS

Impairments of vision and hearing are common in this frail older outpatient population. Functional status, as measured by IADL and ADL scores, is diminished for sensory impaired subjects. Combined vision and hearing impairments have a greater effect on function than single sensory impairments and influence functional status independent of mental status and comorbid illness. Overall, these results suggest that interventions to improve sensory function may improve functional independence.

Orthostatic blood pressure changes and arterial baroreflex sensitivity in elderly subjects

BACKGROUND

orthostatic hypotension in elderly people is often attributed to diminished afferent baroreflex sensitivity, but this has not been demonstrated. We examined the hypothesis that postural change in blood pressure is related to baroreflex sensitivity, independent of the confounding effect of baseline blood pressure.

METHODS

we studied 25 active, untreated elderly subjects free of postural symptoms (mean age 70 +/- 1 years): 16 with hypertension (clinic blood pressure 194 +/- 6/98 + 3 mmHg) and nine normotensive controls (clinic blood pressure 134 + 3/77 + 3 mmHg). We assessed baroreflex sensitivity from the heart rate and blood pressure responses to the Valsalva manoeuvre and a pressor and depressor stimulus (bolus phenylephrine injection or sodium nitroprusside infusion respectively). Subjects were then passively tilted to 60 degrees and maximum changes in systolic blood pressure, heart rate, forearm blood flow and forearm vascular resistance recorded.

RESULTS

maximum change in systolic blood pressure with head-up tilt was correlated with supine systolic blood pressure (r = 0.60, P = 0.001). Maximum change in systolic blood pressure with orthostasis was greater in the hypertensive subjects (45 +/- 4 mmHg versus 29 +/- 6, P = 0.04) and the heart rate increment was less (16 +/- 2 bpm versus 24 +/- 4, P = 0.02). The increase in forearm vascular resistance with tilt was similar in the two groups (47 +/- 11 versus 38 +/- 7 units, P = 0.52). All three methods of assessing baroreflex sensitivity showed a reduction in the hypertensive subjects (all P < or = 0.02). Lower values of baroreflex sensitivity were related to greater falls in systolic blood pressure with tilt, after adjustment for the baseline level of systolic blood pressure.

CONCLUSIONS

we found a relationship between baroreflex sensitivity and the systolic blood pressure fall with orthostasis, even after adjustment for prevailing systolic blood pressure. Despite equivalent changes in forearm vascular resistance with tilt, greater falls in systolic blood pressure were seen in hypertensive subjects than in normotensive controls, due in part to an inadequate baroreflex-mediated heart rate response. The postural fall in blood pressure often observed in elderly hypertensive subjects may be related to the reduced baroreflex sensitivity seen in this condition.