Biomedical subjects

Lewis B Morgenstern

Publications and source records attributed to Lewis B Morgenstern.

30 records · Page 2Linked to original sources

PubMed2004

Designing multi-ethnic stroke studies: the Brain Attack Surveillance in Corpus Christi (BASIC) project.

The Brain Attack Surveillance in Corpus Christi (BASIC) project is a population-based stroke study comparing Mexican Americans and non-Hispanic whites. Extensive effort is made to detect all patients regardless of ethnicity and ensure equal participation in the interview among both groups. We describe here the study's design and process evaluation with a focus on reducing bias in case ascertainment and participation. During the first 28 months of the project, 11,829 subjects were screened. Availability of neuroimaging did not differ by ethnicity (P=0.22), nor did confidence in the validated diagnosis of stroke (P=0.10). Participation rate in the interview also did not differ by ethnicity (P=0.92). There was excellent agreement of ethnic classification between chart abstraction and self-report (kappa=0.94, P<0.001). We conclude that multi-ethnic stroke comparison studies are feasible. Utilizing epidemiologic principles to design, recruit and analyze data are critical. Process evaluation to examine for sources of bias is important to study conduct.

Aged↗

PubMed2003

Access to care, acculturation, and risk factors for stroke in Mexican Americans: the Brain Attack Surveillance in Corpus Christi (BASIC) project.

BACKGROUND AND PURPOSE: Mexican Americans are the largest subgroup of Hispanic Americans, now the most numerous US minority population. We compared access to care, acculturation, and biological risk factors among Mexican American and non-Hispanic white stroke patients and the general population. METHODS: The Brain Attack Surveillance in Corpus Christi project is a population-based stroke surveillance study conducted in southeast Texas. All stroke cases were ascertained through active and passive surveillance from January 2000 through April 2002 and compared with population estimates from a random-digit telephone survey. RESULTS: Compared with non-Hispanic white stroke patients (n=405), Mexican American stroke patients (n=403) were less likely to have graduated from high school (odds ratio [OR], 15.4; 95% confidence interval [CI], 10.6 to 22.4) and more likely to earn less than 20 000 dollars per year (OR, 6.5; 95% CI, 4.5 to 9.4). Mexican American stroke patients were more likely to have diabetes (OR, 2.7; 95% CI, 2.0 to 3.7) and less likely to have atrial fibrillation (OR, 0.5; 95% CI, 0.4 to 0.8). Compared with population estimates (n=719), stroke was associated with diabetes (Mexican Americans: OR, 3.6; 95% CI, 2.2 to 5.8; non-Hispanic whites: OR, 3.0; 95% CI, 1.7 to 5.5), hypertension (Mexican Americans: OR, 2.8; 95% CI, 1.8 to 4.3; non-Hispanic whites: OR, 3.3; 95% CI, 2.2 to 5.0), lower incomes (Mexican Americans: OR, 3.4; 95% CI, 2.1 to 5.4; non-Hispanic whites: OR, 3.0; 95% CI, 1.7 to 5.2), and lower educational attainment (Mexican Americans: OR, 5.1; 95% CI, 3.2 to 8.1; non-Hispanic whites: OR, 4.5; 95% CI, 2.2 to 9.3). CONCLUSIONS: Biological and social variables are associated with stroke to a similar extent in both Mexican Americans and non-Hispanic whites. Health behavior interventions for both populations may follow from this work. Stroke disparities between these populations may be explained only partially by differences in the prevalence of currently identified biological and social factors.

Acculturation↗

PubMed2003

Sustained benefit of a community and professional intervention to increase acute stroke therapy.

BACKGROUND: The ultimate test of an educational intervention is the sustainability of the effect after the intervention ceases. METHODS: The TLL Temple Foundation Stroke Project was a quasi-experimental study aimed at increasing Food and Drug Administration-approved acute stroke therapy in a nonurban community in east Texas. During the intensive community and professional intervention (phase 2), significantly more patients with acute stroke received intravenous tissue plasminogen activator (tPA) compared with the preintervention period (phase 1). In the comparison community, no change was noted. We present the results of tPA treatment in the 6 months after the intervention ended (phase 3). RESULTS: Two hundred thirty-eight patients had a validated stroke during phase 3. Among patients who experienced an ischemic stroke, 11.2% in the intervention group received intravenous tPA compared with 2.2% in phase 1 (P =.007). In the comparison group, 1.4% received intravenous tPA in phase 3 compared with 0.7% in phase 1 (P>.99). Among eligible candidates for treatment, 69.2% were treated in phase 3 in the intervention community compared with 13.6% in phase 1 (P =.002). In the comparison group, 20.0% were treated in phase 3 compared with 6.7% in phase 1 (P =.45). There was 1 protocol violation among the 9 patients treated in the intervention community in phase 3. CONCLUSIONS: There was a sustained benefit of the intervention in increasing tPA treatments in the intervention community even after cessation of the educational effort. Treatments in the control community remained few through all 3 phases of the study. A carefully planned multilevel intervention can improve community stroke treatments even in a nonurban community.

Drug Utilization↗

PubMed2003

Major risk factors for aneurysmal subarachnoid hemorrhage in the young are modifiable.

BACKGROUND AND PURPOSE: To identify risk factors for subarachnoid hemorrhage (SAH) and intracerebral hemorrhage, we designed a case-control study of men and women 18 to 49 years of age (the Hemorrhagic Stroke Project [HSP]). This report focuses on SAH. METHODS: Patients were recruited from 44 hospitals in the United States. Cases with SAH must have had a ruptured aneurysm documented by angiography or surgery. Two controls, identified by random digit dialing and matched to each patient for age, sex, race, and telephone exchange, were sought for each case subject. RESULTS: Between 1994 and 1999, 425 patients with SAH were enrolled in HSP, and 312 cases met the criteria for aneurysmal SAH. The present analyses also included 618 matched controls. Of the 312 cases, 66% were current cigarette smokers compared with 30% of controls (adjusted odds ratio [OR], 3.73; 95% CI, 2.67 to 5.21). Cocaine use within the previous 3-day period was reported by 3% of cases and no controls (bivariate exact OR, 24.97; 95% exact CI, 3.95 to infinity; adjusted estimate not calculable). Other independent risk factors in the multivariable model included hypertension (adjusted OR, 2.21; 95% CI, 1.48 to 3.29), low body mass index (OR, 1.59; 95% CI, 1.08 to 2.35), primary family history of hemorrhagic stroke (OR, 3.83; 95% CI, 1.73 to 8.46), caffeine in pharmaceutical products (OR, 2.48; 95% CI, 1.19 to 5.20), lower educational achievement (OR, 2.36; 95% CI, 1.44 to 3.87), and nicotine in pharmaceutical products (adjusted estimate not calculable). CONCLUSIONS: Aneurysmal SAH may be largely a preventable disease among the young and middle-aged because several prevalent risk factors can be modified by medication (eg, hypertension) or behavioral change (eg, cigarette smoking, cocaine use). The association of caffeine and nicotine in pharmaceutical products and aneurysmal SAH warrants further study.

Adolescent↗

PubMed2003

Improving efficiency of stroke research: the Brain Attack Surveillance in Corpus Christi study.

We studied whether a computer algorithm or abstractor could diagnose stroke as well as a fellowship-trained stroke neurologist. As part of an ongoing prospective, community-based stroke surveillance project, a diagnostic algorithm was developed, and patients' neurologic signs and symptoms were collected in a computerized database. The abstractors were blinded to the results of this algorithm and were asked to verify whether the patient had a stroke. The separate results of the computer and abstractor were compared with the final diagnosis given by the blinded neurologist. From 1 January through 31 July 2000, 3418 cases were screened. The abstractors yielded sensitivity 91%, specificity 97%, positive predictive value (PPV) 85%, and negative predictive value (NPV) 99%. Three computer algorithms were evaluated. The sensitivities ranged from 83% to 96%, specificity ranged from 88% to 97%, PPV ranged from 54% to 81%, and NPV ranged from 97% to 99%. The use of computer verification or abstractors may obviate the need for physician stroke verification and may greatly improve study efficiency.

Algorithms↗

PubMed2002

Comparison of active and passive surveillance for cerebrovascular disease: The Brain Attack Surveillance in Corpus Christi (BASIC) Project.

To provide a scientific rationale for choosing an optimal stroke surveillance method, the authors compared active surveillance with passive surveillance. The methods involved ascertaining cerebrovascular events that occurred in Nueces County, Texas, during calendar year 2000. Active methods utilized screening of hospital and emergency department logs and routine visiting of hospital wards and out-of-hospital sources. Passive means relied on International Classification of Diseases, Ninth Revision (ICD-9), discharge codes for case ascertainment. Cases were validated by fellowship-trained stroke neurologists on the basis of published criteria. The results showed that, of the 6,236 events identified through both active and passive surveillance, 802 were validated to be cerebrovascular events. When passive surveillance alone was used, 209 (26.1%) cases were missed, including 73 (9.1%) cases involving hospital admission and 136 (17.0%) out-of-hospital strokes. Through active surveillance alone, 57 (7.1%) cases were missed. The positive predictive value of active surveillance was 12.2%. Among the 2,099 patients admitted to a hospital, passive surveillance using ICD-9 codes missed 73 cases of cerebrovascular disease and mistakenly included 222 noncases. There were 57 admitted hospital cases missed by active surveillance, including 13 not recognized because of human error. This study provided a quantitative means of assessing the utility of active and passive surveillance for cerebrovascular disease. More uniform surveillance methods would allow comparisons across studies and communities.

Cerebrovascular Disorders↗

PubMed2002

Sex and acute stroke presentation.

STUDY OBJECTIVES: We determine whether a sex difference exists for acute stroke emergency department presentation. METHODS: The TLL Temple Foundation Stroke Project is a prospective observational study of acute stroke management that identified 1,189 validated strokes in nonurban community EDs from February 1998 to March 2000. Structured interview of the patient and the person with the patient at symptom onset identified the symptom or symptoms that prompted the patient to seek medical attention. Interview data were available for 1,124 (94%) patients. A physician blinded to sex classified the reported symptoms into 14 categories. RESULTS: Nontraditional stroke symptoms were reported by 28% of women and 19% of men (odds ratio 1.62; 95% confidence interval 1.2 to 2.2). Nontraditional stroke symptoms, pain (men 8%, women 12%) and change in level of consciousness (men 12%, women 17%), were more often reported by women. Traditional stroke symptoms, imbalance (men 20%, women 15%) and hemiparesis (men 24%, women 19%), were reported more frequently by men. Trends were also found for women to present with nonneurologic symptoms (men 17%, women 21%) and men to present with gait abnormalities (men 11%, women 8%). There was no sex difference in the mean number of symptoms reported by an individual patient. CONCLUSION: This study suggests that a sex difference exists in reporting of acute stroke symptoms. Women with validated strokes present more frequently with nontraditional stroke symptoms than men. Recognition of this difference might yield faster evaluation and management of female patients with acute stroke eligible for acute therapies.

Aged↗

PubMed2002

Safety of tissue plasminogen activator for acute stroke in menstruating women.

BACKGROUND: Menses is a theoretical contraindication to intravenous tissue plasminogen activator (tPA) treatment. We sought to establish the safety of intravenous tPA in the treatment of acute ischemic stroke in women who are actively menstruating. SUMMARY OF REPORT: We provide a case report and review of the National Institute of Neurological Disorders and Stroke (NINDS) database for women coded as actively menstruating. Nine subjects were coded as actively menstruating in the NINDS trial (4 placebo and 5 in the treatment). One subject in the treatment group who had a 1-year history of dysfunctional uterine bleeding required emergent uterine artery ligation. We also report a case of a woman requiring transfusion after intravenous tPA administration for acute ischemic stroke. CONCLUSIONS: Intravenous tPA may be administered relatively safely in women who are menstruating and should be used with caution in women with a history of dysfunctional uterine bleeding. Potential patients should be advised that they might require transfusion for increased menstrual flow.

Acute Disease↗

PubMed2002

Shortening the NIH Stroke scale for use in the prehospital setting.

BACKGROUND AND PURPOSE: Prehospital stroke scales should identify stroke patients and measure stroke severity. The goal of this study was to identify a subset of the 15 items in the National Institutes of Health Stroke Scale (NIHSS-15) that measures stroke severity and predicts outcomes. METHODS: Using 2 distinct data sets from acute stroke clinical trials, we derived and validated shortened versions of the NIHSS (sNIHSS). Stepwise logistic regression and bootstrap techniques were used in selection of NIHSS-15 items. Areas under the receiver operator characteristic curve (C statistics) were used to compare predictive performance of logistic models incorporating differing versions of the NIHSS. RESULTS: The derivation analyses suggested the 8 NIHSS-15 items that were most predictive of "good outcome" 3 months after stroke, in order of decreasing importance: right leg item, left leg, gaze, visual fields, language, level of consciousness, facial palsy, and dysarthria. The sNIHSS-8 comprises all 8 and the sNIHSS-5, the first 5. In the validation models, C statistics were NIHSS-15=0.80, sNIHSS-8=0.77, and sNIHSS-5=0.76. Statistical comparisons suggested that the NIHSS-15 had better predictive performance than the sNIHSS-8 or the sNIHSS-5; the absolute difference in C statistics was small. There was no significant difference between the sNIHSS-8 and the sNIHSS-5. CONCLUSIONS: Much of the predictive performance of the full NIHSS-15 was retained with a shortened scale, the sNIHSS-5. Shortening the NIHSS-15 will facilitate its use during prehospital evaluations. The sNIHSS severity information may be useful to triage acute stroke patients in communities and to provide a baseline stroke severity for prehospital acute stroke trials.

Acute Disease↗

PubMed2002

Acetaminophen for altering body temperature in acute stroke: a randomized clinical trial.

BACKGROUND AND PURPOSE: Mild alterations in temperature have prominent effects on ischemic cell injury and stroke outcome. Elevated core body temperature (CBT), even if mild, may exacerbate neuronal injury and worsen outcome, whereas hypothermia is potentially neuroprotective. The antipyretic effects of acetaminophen were hypothesized to reduce CBT. METHODS: This was a randomized, controlled clinical trial at 2 university hospitals. Patients were included if they had stroke within 24 hours of onset of symptoms, National Institutes of Health Stroke Scale (NIHSS) score > or =5, initial CBT <3 8.5 degrees C, and white blood cell count < 12 600 cells/mm(3); they were excluded if they had signs of infection, severe medical illness, or contraindication to acetaminophen. CBT was measured every 30 minutes. Patients were randomized to receive acetaminophen 650 mg or placebo every 4 hours for 24 hours. The primary outcome measure was mean CBT during the 24-hour study period; the secondary outcome measure was the change in NIHSS. RESULTS: Thirty-nine patients were randomized. Baseline CBT was the same: 36.96 degrees C for acetaminophen versus 36.95 degrees C for placebo (P=0.96). During the study period, CBT tended to be lower in the acetaminophen group (37.13 degrees C versus 37.35 degrees C), a difference of 0.22 degrees C (95% CI, -0.08 degrees C to 0.51 degrees C; P=0.14). Patients given acetaminophen tended to be more often hypothermic <36.5 degrees C (OR, 3.4; 95% CI, 0.83 to 14.2; P=0.09) and less often hyperthermic >37.5 degrees C (OR, 0.52; 95% CI, 0.19 to 1.44; P=0.22). The change in NIHSS scores from baseline to 48 hours did not differ between the groups (P=0.93). CONCLUSIONS: Early administration of acetaminophen (3900 mg/d) to afebrile patients with acute stroke may result in a small reduction in CBT. Acetaminophen may also modestly promote hypothermia <36.5 degrees C or prevent hyperthermia >37.5 degrees C. These effects are unlikely to have robust clinical impact, and alternative or additional methods are needed to achieve effective thermoregulation in stroke patients.

Acetaminophen↗

PubMed2002

Improving delivery of acute stroke therapy: The TLL Temple Foundation Stroke Project.

BACKGROUND AND PURPOSE: Only a small minority of acute stroke patients receive approved acute stroke therapy. We performed a community and professional behavioral intervention project to increase the proportion of stroke patients treated with approved acute stroke therapy. METHODS: This study used a quasi-experimental design. Intervention and comparison communities were compared at baseline and during educational intervention. The communities were based in 5 nonurban East Texas counties. The multilevel intervention worked with hospitals and community physicians while changing the stroke identification skills, outcome expectations, and social norms of community residents. The primary goal was to increase the proportion of patients treated with intravenous recombinant tissue plasminogen activator (rTPA) from 1% to 6% of all cerebrovascular events in the intervention community. RESULTS: We prospectively evaluated 1733 patients and validated 1189 cerebrovascular events. Intravenous rTPA treatment increased from 1.38% to 5.75% among all cerebrovascular event patients in the intervention community (P=0.01) compared with a change from 0.49% to 0.55% in the comparison community (P=1.00). Among the ischemic stroke patients, an increase from 2.21% to 8.65% was noted in the intervention community (P=0.02). The comparison group did not appreciably change (0.71% to 0.86%, P=1.00). Of eligible intravenous rTPA candidates, treatment increased in the intervention community from 14% to 52% (P=0.003) and was unchanged in the comparison community (7% to 6%, P=1.00). CONCLUSIONS: An aggressive, multilevel stroke educational intervention program can increase delivery of acute stroke therapy. This may have important public health implications for reducing disability on a national level.

Acute Disease↗

PubMedDate not supplied

Use of death certificates to study ethnic-specific mortality.

OBJECTIVES: The Hispanic population in the United States represents more than 40 million individuals, with Mexican Americans (MA) as the largest subgroup. To assess the utility of death certificates and medical records as the source of race/ethnicity data for epidemiologic studies, we compared self-reported race/ ethnicity to race/ethnicity recorded on death certificates and medical records in a bi-ethnic, non-immigrant U.S. community with a significant MA population. METHODS: This study utilized data collected from a subset of 1,856 participants of the Brain Attack Surveillance in Corpus Christi (BASIC) project. In-person interviews were conducted to determine self-reported race/ethnicity. Of those interviewed, 480 subsequently expired. Using self-reported race/ethnicity as the gold standard, we determined percent agreement, sensitivity, and specificity of the death certificate and medical record. RESULTS: Of the 480 subjects, 259 self-reported their race/ethnicity as non-Hispanic white (NHW), 195 self-reported as MA, and 26 self-reported as non-Hispanic black. Median age was 78.5 years and 55.8% were female. Percent agreement between self-reported race/ethnicity and race/ethnicity recorded on the death certificate and medical record was 97.1% and 96.3% respectively. Five percent of MAs were misclassified as NHW on their death certificates and 3% on their medical records. CONCLUSIONS: Results indicated that Hispanic designation recorded on death certificates and medical records in this community was largely consistent with that of self-report. This study suggests that vital statistics data in non-immigrant U.S. Hispanic communities can be used with confidence to investigate ethnic-specific aspects of disease and mortality. Similar studies in other multi-racial communities should be conducted to confirm and generalize these results.

Aged↗