George W. Divine

Measurement of motor recovery after stroke. Outcome assessment and sample size requirements.

Background and Purpose The purpose of this study was to analyze recovery of motor function in a cohort of patients presenting with an acute occlusion in the carotid distribution. Analysis of recovery patterns is important for estimating patient care needs, establishing therapeutic plans, and estimating sample sizes for clinical intervention trials. Methods We prospectively measured the motor deficits of 104 stroke patients over a 6-month period to identify earliest measures that would predict subsequent motor recovery. Motor function was measured with the Fugl-Meyer Assessment. Fifty-four patients were randomly assigned to a training set for model development; 50 patients were assigned to a test set for model validation. In a second analysis, patients were stratified on basis of time and stroke severity. The sample size required to detect a 50% improvement in residual motor function was calculated for each level of impairment and at three points in time. Results At baseline the initial Fugl-Meyer motor scores accounted for only half the variance in 6-month motor function (r2=0.53, p<0.001). After 5 days, both the 5-day motor and sensory scores explained 74% of the variance (p<0.001). After 30 days, the 30-day motor score explained 86% of the variance (p<0.001). Application of these best models to the test set confirmed the results obtained with the training set. Sample-size calculations revealed that as severity and time since stroke increased, sample sizes required to detect a 50% improvement in residual motor deficits decreased. Conclusions Most of the variability in motor recovery can be explained by 30 days after stroke. These findings have important implications for clinical practice and research.

The unit of analysis error in studies about physicians' patient care behavior

Objective:To estimate the frequency with which patients are incorrectly used as the unit of analysis among statistical calculations in published studies of physicians’ patient care behavior.Design:Retrospective review of studies published during 1980–1990.Articles:54 articles retrieved by a computerized search using medical subject beadings for physicians and study characteristics. Article selection criteria included the requirement that the physician should have been the correct unit of analysis.Intervention:Presence of the error was determined by consensus using published criteria.Main results:The error was present in 38 articles (70%). The number of study physicians was reported in 35 articles (65%). The error was found in 57% of articles that reported the number of study physicians and in 95% of those that did not. The error rate was not lower among articles published more recently nor among those published in journals with higher rates of article citations in the medical literature.Conclusion:The unit of analysis error occurs frequently and can generate artificially low p values. Failure to report the number of study physicians can be a clue that this type of error has been made.

Impairment of physical and psychosocial function in recurrent syncope

Physical and psychosocial function have rarely been assessed in syncope. We used two valid and reliable measures of health status, the Sickness Impact Profile (SIP) and the Symptom Checklist 90 (SCL-90-R), to assess functional impairment in 62 patients with recurrent syncope seen in a syncope specialty clinic. Mean total SIP scores were markedly elevated at 17 (SD = 14), indicating a level of impairment similar to severe rheumatoid arthritis and chronic low back pain. SIP psychosocial scores were significantly greater than SIP physical scores (20 vs 11, p less than 0.0001). SCL-90-R scores were also high, comparable to those of psychiatric inpatients. Somatization, anxiety and depression dimensions of the SCL-90-R were particularly elevated. SCL-90-R subscale scores were highly correlated with SIP psychosocial scores (all r greater than 0.4, and p less than 0.001). Neither age nor number of comorbid diseases correlated with measures of psychosocial function, suggesting that syncope itself causes psychosocial impairment. Although this was a referral population, these data suggest that function can be seriously impaired by syncope, that the degree of impairment is similar to that reported in other chronic diseases, and that syncope leads to significantly greater psychosocial than physical impairment.

Incremental diagnostic yield of loop electrocardiographic recorders in unexplained syncope

The Holter monitor, the most frequently used diagnostic test in patients with syncope, is nondiagnostic in over 90% of cases. This study sought to determine the impact of a new noninvasive device, the cardiac loop electrocardiographic (ECG) recorder, after Holter monitoring in 57 patients with unexplained syncope. All patients underwent a standardized evaluation protocol and were the monitor for up to 1 month. In 14 patients, loop recording definitively determined whether an arrhythmia was the cause of symptoms (diagnostic yield 25%; 95% confidence intervals 14 to 38%). Diagnoses included unsuspected ventricular tachycardia (1 patient), high grade atrioventricular block (2 patients), supraventricular tachycardia (1 patient), asystole or junctional bradycardia from neurally mediated syncope (3 patients) and normal cardiac rhythms (the remaining 7 patients). Follow-up of all patients diagnosed as having nonarrhythmic syncope by loop recording showed that none of these patients died suddenly. Cardiac loop ECG recording is an important new diagnostic test in patients with syncope unexplained by Holter monitoring.

Recurrent syncope as a chronic disease: preliminary validation of a disease-specific measure of functional impairment.

Background: A disease-specific measure of functional health in syncope would provide an important outcome measure for use either in clinical trials or in the clinical management of patients with recurrent syncope.Methods arid Measurements: In a previous study the authors used formal functional status measures to determine physical and psycho-social impairment in recurrent syncope. This study provides a preliminary assessment of a disease-specific measure of function. The measure was pilot tested on 84 subjects, and validated in a separate cohort of 49 patients. The measure consists of 1) an 11-question matrix of yes/no questions, assessing the ways that syncope interferes with a patient’s life (the result is expressed as a proportion of the total number of ways that syncope might interfere and is called the Impairment Score), and 2) three Likert-scale questions that assess the patient’s fear and worry about syncope. Correlations were obtained between scores on the disease-specific measure and other measures of functional health.Results: Among the 49 patients in the test cohort, final scores on the disease-specific measure correlated with both physical and psycho-social dimension scores on a measure of functional status, the Sickness Impact Profile (r=0.35–0.36, p=0.01), and with five of ten subscale scores on a measure of psychological distress, the Symptom Checklist 90-R (r=0.30–0.43, p=0.004–0.02).Conclusions: This new disease-specific quality-of-life measure in syncope measures both physical and psychosocial components of impairment and could be a valuable adjunct in measuring outcomes in syncope patients.

Expenditures in caring for patients with dementia who live at home.

OBJECTIVES Given the national interest in progressive dementia, we estimated expenditures incurred in caring for dementia patients who live at home. METHODS Primary caregivers of 264 patients from a university-based memory disorders clinic were interviewed at baseline and asked to keep service use diaries for 6 months; 141 caregivers who returned the diaries are the focus of this report. We examined both formal and informal services (distinguished by whether money was exchanged) and associated expenditures. RESULTS Neither caregivers returning diaries nor their patients differed at baseline from those not returning diaries and their patients. Expenditures incurred over 6 months were extensive for both formal (

The Influence of Hyperglycemia on Outcome of Cerebral Infarction

6986) and informal (

Racial variations in ischemic stroke-related physical and functional impairments.

786) services. Out-of-pocket expenditures were high (e.g., in-home companion or sitter, adult day care, visiting nurse). Multivariable analyses indicated that patients with more severe symptoms of dementia and families with higher incomes reported significantly higher expenditures. CONCLUSIONS The expense of caring for patients with progressive dementia living at home may be higher than previously estimated and frequently involves expenses paid directly by patients and their families.

The impact of psychologic factors on measurement of functional status. Assessment of the sickness impact profile.

OBJECTIVE To determine whether hyperglycemia in the acute stroke period is associated with worse survival and functional outcome after accounting for acute stress response and chronic hyperglycemia. DESIGN Prospective, county-wide, multicenter cohort study. SETTING A community hospital, a university hospital, and a Veterans Affairs hospital. PATIENTS A cohort of 146 patients hospitalized with new atherothrombotic stroke. MEASUREMENTS Admission blood glucose concentration, demographic characteristics of patients, 24-hour urinary catecholamine, serum cortisol, and glycosylated hemoglobin levels; outcomes included mortality and functional outcome (Barthel index and Fugl-Meyer score) at 5, 30, 90, and 180 days after stroke. RESULTS Of the 996 patients with possible acute stroke who were screened, 146 (15%) were eligible for and consented to participate in the study; in most cases, exclusion from study was based on the absence of acute, atherothrombotic stroke. Overall, no evidence was found of a significant univariate association between admission blood glucose level and survival (relative risk, 1.02; 95% Cl, 0.94 to 1.09) or functional outcome (univariate regression coefficient for adjusted Fugl-Meyer score at day 30, - 0.36; Cl, - 1.08 to 0.27). This absence of an association persisted after adjustment for significant predictors of outcome in a multivariate model. CONCLUSIONS These data do not support an association between level of glycemia and outcome from acute stroke.

Syncope in young adults: evidence for a combined medical and psychiatric approach.

Background and Purpose We sought to determine whether there are racial differences in physical and functional impairments resulting from an initial ischemic stroke. Methods We conducted a prospective, county-wide, multisite cohort study including a university hospital, a community hospital, and a Veterans Affairs hospital. The study population was an inception cohort of 145 patients hospitalized for ischemic stroke. Physical and functional impairments were measured using a modified form of the Fugl-Meyer test and the Barthel Index, respectively. Nurses trained to use these tests made assessments at admission and 5, 30, 90, and 180 days after admission. Patient and disease-specific data along with treatment data and vital status were collected. Results Forty-one patients (28%) were black. Compared with whites, black stroke patients were more likely to be widowed (51% versus 26%) and hypertensive (83% versus 63%) but less likely to be male (42% versus 69%) and alert on admission (66% versus 76%). There were no racial differences in mortality. Physical impairment was significantly more severe in black than in white patients at admission, and although physical impairment improved, it remained significantly worse in blacks. Functional impairment was also greater in black patients initially but was similar to that in white patients 90 days after the event. Multivariable analyses confirmed these findings. Conclusions These results indicate that blacks may have greater residual physical deficits from stroke than whites.