Performance of elderly African American and White community residents on the CERAD Neuropsychological Battery.

The CERAD Neuropsychological Battery, includes 7 measures: Verbal Fluency; Modified Boston Naming; Mini-Mental State: Word List Learning, Recall and Recognition; Constructional Praxis. It was originally developed to evaluate patients with a clinical diagnosis of Alzheimer's disease, but is increasingly used in epidemiological studies of the incidence and prevalence of dementia in the elderly. The current study reports norms for African American and White representative community residents 71 years of age and older in North Carolina, and compares performance with that of African Americans in Indianapolis and with Whites in the Monongahela Valley, Pennsylvania. For all 3 studies, increased education and younger age was related to better performance on each of the 7 measures. Sex differences, when present, tended to favor women. Although on average African Americans performed more poorly than Whites, with demographic characteristics controlled, no significant racial differences were found in the North Carolina sample. Both African American and White participants in North Carolina performed more poorly than their racial counterparts in the other 2 studies, possibly because of selection-induced differences in health and educational status. Nevertheless, the use of an identical evaluation battery, such as the CERAD neuropsychologic instrument, facilitates comparisons not otherwise possible, and should be encouraged.

Abnormal signal-averaged electrocardiogram (SAECG) in obesity.

OBJECTIVE: The occurrence of small high-frequency electrocardiogram (ECG) potentials (1 to 20 microV) seen at the end of the QRS complex and into the ST segment have been correlated with increased risk for ventricular arrhythmias and sudden cardiac death. Computer-assisted analysis of these "late potentials" by signal-averaged electrocardiography (SAECG) has been studied and utilized to predict the likelihood of ventricular arrhythmias in various clinical states. Obesity is associated with significant cardiovascular morbidity and sudden death. Ventricular arrhythmias are postulated causes. We studied the occurrence of late potentials in a randomly selected group of obese patients and healthy volunteers. RESEARCH METHODS AND PROCEDURES: We performed SAECG on 105 subjects. Of these, 62 were obese ambulatory patients with body mass index (BMI) of >30 kg/m2, whereas 43 were healthy asymptomatic volunteers with a BMI of <30 kg/m2. Patients with a history of clinical heart disease and pulmonary disease, electrolyte abnormalities, recent hospitalizations, or abnormal screening ECG or taking medications known to alter the QRS interval were excluded. At least 250 beats were analyzed with a noise level of <0.50 microV. Criteria of a late potential include QRS duration >114 ms, high-frequency low amplitude >38 ms, and root-mean-square voltage <20 microV. Patients were divided into four subgroups based on BMI values. The prevalence of SAECG abnormalities in each BMI subgroup was studied. We utilized multiple logistic regression analysis to study the effect of obesity, hypertension, and diabetes mellitus on abnormal SAECG results. RESULTS: Compared to age- and sex-matched healthy volunteers with BMI of <30 kg/m2, obese patients with BMI of >30 kg/m2 had significantly more abnormalities on SAECG (4.6% vs. 55%). In the obese group, the prevalence and number of abnormalities increased with increase in BMI (35% in the BMI 31 to 40 kg/m2 subgroup, 86% in the BMI 41 to 50 kg/m2 subgroup, and 100% in patients with BMI of >50 kg/m2). Multiple logistic regression analysis shows that BMI is an independent predictor variable of abnormal SAECG results in obese patients (n = 62) with BMI of >30 kg/m2 as well as in all study subjects (n = 105). BMI also predicts abnormality of each abnormal SAECG criterion in both obese and all subjects. Hypertension was found to influence the QRS duration alone in obese and all subjects. DISCUSSION: Obesity is associated with increased occurrence of abnormal SAECG results. These abnormalities are found both in obese patients with and without hypertension and/or diabetes. Obesity is an independent predictor variable of abnormal SAECG results. A history of hypertension predicts abnormality of QRS duration only.

The prevalence and 3-year incidence of dementia in older Black and White community residents.

OBJECTIVE: To determine the prevalence and 3-year incidence of dementia in Blacks and Whites age 65 and older in a five-county Piedmont area of North Carolina. DESIGN: Stratified random sample of members of the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE) (baseline n = 4,136; 55% Black; weighted n = 28,000). Prevalence study members were differentially selected on the basis of score on the Short Portable Mental Status Questionnaire at the second in-person Duke EPESE wave. Incidence study members included all persons with obvious cognitive decline over a 3-year period, and a 10% sample of the remainder. MEASUREMENTS: Self- and informant report on health history, functional status, and memory. Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Neuropsychology Battery administered to all subjects, and CERAD Clinical Battery to those with impaired memory. Clinical consensus to determine presence and type of dementia. RESULTS: Prevalence of dementia for persons > or =68 years old was 0.070 (95% confidence interval = 0.021-0.119) for Blacks and 0.072 (0.022-0.122) for Whites. Rates for Black men (0.078, 0.001-0.155) exceeded those for Black women (0.066, 0.003-0.129), but gender rates for Whites were reversed (men: 0.044, 0.000-0.103), (women: 0.087, 0.015-0.160). Neither race nor gender differences were significant. Prevalence of dementia increased through age 84 and tapered off thereafter. Three-year incidence of dementia was 0.058 (0.026-0.090) for Blacks and 0.062 (0.027-0.097) for Whites. Neither race nor gender differences were significant. Incidence increased through age 84, but moderated thereafter for all but Black men. The proportional representation of different types of dementia varied little by race. CONCLUSION: Prevalence, 3-year incidence, and types of dementia are comparable in Black and White elderly in the Piedmont area of North Carolina.

Detection of viable Giardia cysts by amplification of heat shock-induced mRNA.

Primers obtained from gene sequences coding for heat shock proteins (HSP) were used to specifically detect enteric protozoans of the genus Giardia. The HSP primers amplified Giardia DNA or the corresponding RNA sequences obtained from lysed cysts and gave a 163-bp product. Since the presence of the product did not indicate whether the cysts were viable, these amplifications are a presence/absence test only. In contrast, amplification of heat shock-induced mRNA utilizing the same HSP primers was indicative of viable Giardia cysts. The limit of sensitivity of the presence/absence test was 1 cyst, whereas for the viability test it was 10 cysts. Thus, viable Giardia cysts can be rapidly and specifically detected with great sensitivity through the use of PCR amplifications.

The consortium to establish a registry for Alzheimer's Disease (CERAD). Part XIII. Obtaining autopsy in Alzheimer's disease.

Although autopsy rates in the United States have been decreasing steadily, the necessity for brain autopsy to confirm Alzheimer's disease (AD) remains. Of 308 consecutively deceased AD patients at 24 CERAD (Consortium to Establish a Registry for Alzheimer's Disease) sites, 167 (54%) were autopsied; 141 (46%) were not. The autopsied and nonautopsied groups were comparable in gender (men, 57.5% versus 49.7%), marital status (married, 69.3% versus 67.1%), age at entry (73 versus 74 years), age at death (76 versus 77 years), and stage of disease at entry (mild, 46% versus 43%). However, the autopsied patients were significantly more likely to be white (94.5% versus 82.1%), to be better educated (13.1 versus 11.3 years), to have been in the study longer (mean, 3.3 versus 2.6 years), and to have had longer total duration of AD (8.1 versus 6.7 years). Of the 24 CERAD sites, 13 stressed the importance of autopsy by dedicating a staff member to seek autopsy and by providing free autopsy and transportation; 11 did not. Logistic regression analysis showed that white race (odds ratio [OR] = 2.74; 95% confidence interval [CI] = 1.10-6.83), increased education (OR = 1.12; 95% CI = 1.04-1.21), and emphasis on autopsy (OR = 4.69; 95% CI = 2.67-8.25) were the only significant factors. Although race and education were important, autopsy was more likely to be obtained when sites dedicated resources to this endeavor.

Intracoronary ST-T alternans during coronary balloon angioplasty.

To evaluate the presence and clinical significance of electrical alternans during PTCA, intracoronary electrocardiography (ic-ECG) was performed in 65 consecutive lesions. ST-T alternans, defined as a beat-to-beat difference in the ST elevation > or = 1 mm, was present in five lesions (7.7%), all in the proximal left anterior descending (LAD) coronary artery. The phenomenon was seen only after 130 sec (mean 174 +/- 57) of balloon inflation. Only two of the five showed ST-T alternans simultaneously on both surface and ic-ECG. One of five patients had premature ventricular contractions following ST-T alternans. Three of these five lesions required a second balloon inflation with duration of > or = 300 sec; there was no ST-T alternans on the second inflation in any of these lesions. We conclude: (1) the detection of ST-T alternans during PTCA is enhanced by use of ic-ECG, (2) electrical alternans during PTCA was seen only in proximal LAD lesions, implicating a large amount of ischemic myocardium as a requisite for the phenomenon, (3) electrical alternans is not immediate, requiring a certain duration of balloon occlusion and hence ischemia to occur, and (4) the absence of ST-T alternans during second balloon inflations suggests ischemic preconditioning may abolish this phenomenon.

Multiple balloon rupture during coronary angioplasty. A case report.

The authors report a case of coronary angioplasty of the left anterior descending artery complicated by multiple balloon rupture. Various balloon types including polyethylene terephthalate and PE 600 (ACS) ruptured at low atmospheric pressure. During balloon rupture, a septal side branch was dissected with severe intimal staining. The authors postulate that a particular lesion morphology was responsible for balloon rupture. Approaches to such lesions using alternative coronary angioplasty techniques and newer technologies are discussed.

Detection of enteroviruses in groundwater with the polymerase chain reaction.

Standard methods for the detection of enteroviruses in environmental samples involve the use of cell culture, which is expensive and time-consuming. The polymerase chain reaction (PCR) is an attractive method for the detection of enteroviruses in water because primary cell culture is not needed and the increased sensitivity of PCR allows detection of the low numbers of target DNAs and RNAs usually found in environmental samples. However, environmental samples often contain substances that inhibit PCR amplification of target DNA and RNA. Procedures that remove substances that interfere with the amplification process need to be developed if PCR is to be successfully applied to environmental samples. An RNA-PCR assay for the detection of enteroviruses in water was developed and used to test a variety of groundwater concentrates and humic acid solutions seeded with poliovirus type 1. The groundwater samples and humic acid solutions were treated with Sephadex G-50, Sephadex G-100, Sephadex G-200, Chelex-100 resin, and a mixed bed resin to remove PCR-inhibitory material from the samples. Sephadex G-100 in combination with Chelex-100 was found to be very effective in removing inhibitory factors for the detection of enteroviruses in groundwater concentrates by PCR. Viruses were detected in two of the groundwater concentrates by the RNA-PCR assay after treatment with Sephadex G-100 plus Chelex-100. This was confirmed by tissue culture, suggesting that the treatment protocol and, subsequently, the RNA-PCR assay are applicable for the detection of enteroviruses in environmental samples.

Angioplasty in ulcerative coronary artery disease: acute results and early follow-up.

The safety and efficacy of percutaneous transluminal coronary angioplasty (PTCA) for stenoses involving ulcerative lesions were retrospectively studied. Seventy-seven patients (62 men and 15 women, mean age 62 +/- 10 years) representing 3.4% of 2,250 patients treated with PTCA during the period January 1, 1988 and June 30, 1990, had pre-PTCA stenoses defined as ulcerated. Twenty-eight (36%) of the stenoses were localized in the left anterior descending coronary artery, 9 (12%) in the left circumflex and 40 (52%) in the right coronary artery. During angioplasty, percent diameter stenosis was reduced from 73 +/- 14% to 22 +/- 13% and transstenotic gradient decreased from 48 +/- 18 to 12 +/- 6 mm Hg. Clinical success (freedom from angina at discharge without coronary bypass surgery, infarction or death) was achieved in 70 patients (90.9%). There were seven unsuccessful cases: three underwent elective coronary bypass surgery, one was managed medically, and three developed a major flow interrupting dissection during the procedure requiring emergency coronary bypass surgery. There were no deaths. At mean follow-up of 7.6 months, 45 of 61 patients (73.7%) remained asymptomatic. One patient needed an elective coronary bypass surgery and five patients had a successful repeat PTCA. In conclusion, PTCA for an ulcerated stenosis can be performed safely with a high primary success rate and a favorable early clinical course.

Use of a morphologic classification to predict clinical outcome after dissection from coronary angioplasty.

To determine if morphology of procedure-associated dissections could help predict clinical outcome, angiograms of 691 coronary artery dissections resulting from percutaneous transluminal coronary angioplasty were categorized according to the National Heart, Lung, and Blood Institute classification system. Classes of dissection were then correlated with clinical outcome: 543 patients with type B dissections had no increase in morbidity and mortality when compared with patients without dissection, with a similar success rate of 93.7%. Complications in this group were low and compared favorably with complication rates in procedures not associated with dissection. One hundred forty-eight procedures associated with dissections of types C to F had a significant increase in in-hospital complications, including acute closure (31%), need for emergency coronary bypass surgery (37%), myocardial infarction (13%) and repeat angioplasty (24%). The overall clinical success rate for those with types C to F dissection was 38%. The differences in clinical success and acute complications between type B and types C to F dissections were statistically significant at p less than 0.0005 for all variables studied. The angiographic morphology of a dissection during coronary angioplasty can predict clinical outcome, aiding in selection of effective therapy.