Cerebral hyperperfusion syndrome after carotid endarterectomy: predictive factors and hemodynamic changes

PURPOSE: It is believed that cerebral hyperperfusion syndrome (CHS) is caused by loss of cerebral autoregulation resulting from chronic cerebral ischemia and that factors including increased intraoperative cerebral blood flow, ipsilateral or contralateral carotid disease, and postoperative hypertension may cause CHS. We describe our experience with CHS, which diverges from published reports. MATERIALS AND METHODS: From March 2000 to February 2002 we performed 455 carotid endarterectomy (CEA) procedures in 404 patients at our institution. CHS developed 1 to 8 days (mean, 3.2 +/- 2.5 days) postoperatively in 9 patients (2%), 6 women and 3 men, whose age ranged from 52 to 84 years (mean, 69 +/- 8 years). Indications for surgery in 8 patients without neurologic symptoms were ipsilateral internal carotid artery (ICA) stenoses ranging from 70% to 99% (mean, 80% +/- 7%); the remaining patient had an ipsilateral stroke, with good clinical recovery, 7 weeks before CEA. Only 1 patient had significant contralateral ICA stenosis (70%). However, 5 patients had undergone contralateral CEA within the previous 3 months. CHS symptoms were severe headache in 5 patients, seizures in 3 patients (1 stroke), and visual disturbance and ataxia in 1 patient. All 404 patients (455 cases) underwent intraoperative and early (2 weeks) postoperative carotid artery duplex scanning. The 9 patients with CHS also underwent carotid artery duplex scanning at the time of the neurologic event. RESULTS: Mean intraoperative ICA volume flow (MICAVF) in the 9 CHS cases was not significantly different from that in the other 446 cases (170 +/- 47 mL/min and 182 +/- 81 mL/min, respectively). However, mean ICA volume flow (481 +/- 106 mL/min) and peak systolic velocity (PSV) (108 +/- 33 cm/s) for the 9 CHS cases measured at onset of symptoms were higher than those for the remaining 446 cases (267 +/- 87 mL/min and 80 +/- 26 cm/s, respectively) (P <.01). Of the 9 patients with CHS, only 3 had systolic blood pressures more than 160 mm Hg at onset of symptoms. Severity of ipsilateral and contralateral ICA stenoses was not significantly different between the 9 CHS cases and the remaining 446 cases. CONCLUSIONS: These data do not corroborate the common belief that CHS occurs preferentially in patients with severe ipsilateral or contralateral carotid disease, increased intraoperative cerebral perfusion, or severe hypertension. Recently performed contralateral CEA (<3 months) appears to be predictive of CHS.     

A comparison of the effects of parental risk markers on pre- and perinatal variables in multiple patient cohorts with fetal alcohol syndrome, autism, Tourette syndrome, and sudden infant death syndrome: an enviromic analysis

The prevalence and magnitude of effect of individual risk markers for specific developmental disorders vary widely across diagnostic category. The four study cohorts for this project were patients from four diagnostic registries in North Dakota for fetal alcohol syndrome (FAS), autism, sudden infant death syndrome (SIDS), and Tourette syndrome. These four cohorts were used to estimate prevalence and magnitude of effect of parental risk markers in patients with developmental disabilities. Cases with North Dakota birth certificates were matched with controls. Using birth certificate data, we then examined five parental risk markers for each cohort and estimated direct and indirect effects for each risk marker by cohort. The authors found two significant paternal risk markers (age in SIDS and education in FAS). Significant maternal markers were age in SIDS, education in FAS, autism, and SIDS. Marital status was a significant risk marker in FAS. Effect sizes were estimated using paired t tests, odds ratios, and population attributable risk (PAR) for both direct and indirect effects for each marker. We estimated both direct and indirect effects to allow for direct comparisons of the differential effect estimates of each of these markers. The direct effect of parental markers differs across diagnostic cohorts of patients. Use of cohorts from similar denominator populations obtained from prevalence studies is a useful methodological tool for estimating the prevalence and magnitude of effect of risk markers.     

Construction work practices and conditions improved after 2-years' participation in the HomeSafe pilot program

This study reevaluated changes in job-site safety audit scores for a cohort of residential construction workers that had protracted exposure to the HomeSafe pilot program for 2(1/2) years. The investigation was a repeated measure of a cohort study underway in the six-county metro area of Denver, Colo. The larger study was a longitudinal, quasi-experimental design with a cohort of residential construction workers within the HomeSafe strategic partnership between Occupational Safety and Health Administration Region VIII and the Home Builders Association of Metropolitan Denver (HBA). Audits were conducted on residential construction sites. Study subjects were construction workers employed by partner or control companies within the study. Repeated measures of 41 companies showed significant improvement (p=.01) in audit scores, increasing from 71.8 to 76.8 after 2(1/2) years in the program. HomeSafe companies out-performed controls (p=.01) for both the retest group and previously unaudited HomeSafe companies. Prolonged exposure in the HomeSafe pilot program resulted in improved audit scores for companies within the program for at least 2 years.     

Comparison of contrast sensitivity,visual acuity,and Humphrey visual field testing in patients with glaucoma

BACKGROUND: Despite their normal or near-normal Snellen visual acuity, patients with glaucoma often complain of "poor" vision. OBJECTIVE: To investigate the relationship between large-letter contrast sensitivity, high-contrast visual acuity, and visual field defects in patients with glaucoma who have 20/40 or better visual acuity. DESIGN :Prospective, cross-sectional case series. PATIENTS AND METHODS: We evaluated 250 eyes of 144 subjects from the Glaucoma Service at the University of Illinois at Chicago College of Medicine. Subjects with a diagnosis of glaucoma, suspected glaucoma, or ocular hypertension who met the 20/40 or better vision requirement were recruited. Visual acuity was measured using the rear-illuminated Lighthouse Visual Acuity Chart at 4 m. Contrast sensitivity was measured using the Pelli-Robson Chart in a front-illuminated box with even luminance across the chart. Visual fields of the patients were measured using the 24-2 full-threshold program on the Humphrey Visual Field Analyzer. RESULTS: A significant correlation (r = 0.57, P < 0.001, n = 127) was found between the visual field mean deviations and the contrast sensitivity scores. The correlation (r = -0.322, P < 0.001, n = 127) was less between the visual field mean deviation and the log MAR visual acuity values, as was the correlation between the contrast sensitivity scores and log MAR visual acuity values (r = -0.370, P < 0.001, n = 127). In the subgroup of patients with chronic open-angle glaucoma, the correlation between the mean visual field deviation and the contrast sensitivity score was higher at 0.689 (P < or = 0.001, n = 62). CONCLUSIONS: Reduced contrast sensitivity is significantly correlated with visual field losses in patients with glaucoma and a visual acuity of 20/40 or better. The study data support the conclusion that, compared with visual acuity, the disease process preferentially affects contrast sensitivity. In our previous work, contrast sensitivity was shown to be more related than visual acuity to real-world function in patients with early glaucomatous changes.     

Drinking course in alcohol-dependent men from adolescence to midlife

OBJECTIVE: Most studies of alcoholism course are based on clinical populations (characterized by severe and chronic alcohol-related problems) or community samples generally covering a short period of time. The current study assessed variations in drinking behaviors from adolescence to midlife in a community sample, describing age of "drinking firsts" (e.g., first alcoholic drink) as well as frequency and duration of periods of abstinence, alcohol dependence (AD) and nonproblem drinking. METHOD: Participants were 354 males with lifetime diagnoses of AD (mean age 50.35) from the Vietnam Era Twin Registry who were assessed regarding alcohol use, abuse and dependence histories (DSM-IV). Using a modified version of Skinner's Lifetime Drinking History, drinking history was reported in terms of distinct drinking periods (phases). RESULTS: Participants reported, on average, 4.18 phases, each lasting 8.22 years, and 12.78 years of AD. More than 60% experienced increases in AD symptoms at least once in successive phases, but only a third of those increases were extreme. In contrast, extreme decreases in AD symptoms were reported by more than 50% of participants. Further, half indicated that they had transitioned from both fewer to greater and from greater to fewer AD symptoms during their drinking years; 8.2% reported no changes in AD symptoms. CONCLUSIONS: Results reflect a wide variation in drinking behaviors among AD men as well as frequent fluctuations in course within individuals' drinking histories. Findings do not support a universal developmental model of alcoholism; notably, they provide counterevidence to the disease model concept of alcoholism course as progressive and chronic.     

Social and environmental enrichment enhances sensitivity to the effects of kappa opioids: studies on antinociception,diuresis and conditioned place preference

Previous studies have reported that social and environmental enrichment can have a marked impact on the functional maturation of the central nervous system and may influence an organism's sensitivity to psychotropic drugs. The purpose of the present study was to examine the effects of social and environmental enrichment on sensitivity to drugs possessing activity at the kappa opioid receptor. Rats were obtained at weaning and randomly assigned to one of two housing conditions: isolated rats were housed individually with no visual or tactile contact with other rats; enriched rats were housed in groups of four in large cages and given various novel objects on a regular basis. After 7 weeks under these conditions, the effects of spiradoline, U69,593 and nalorphine were examined in the warm water, tail-withdrawal procedure. The effects of spiradoline were also examined on urine output and in the conditioned place preference procedure. Enriched rats were more sensitive to the antinociceptive effects of all the opioids examined in the tail-withdrawal procedure, and were more sensitive to the effects of spiradoline on urine output and in the conditioned place preference procedure. Following the conclusion of these tests, housing conditions were reassigned, such that isolated rats were transferred to enrichment cages, and enriched rats were transferred to isolation cages. After 7 weeks under these new conditions, the two groups were equally sensitive to the antinociceptive effects of spiradoline, indicating that the effects of the initial housing conditions were, in part, reversible. Collectively, these data suggest that enriched rats are more sensitive than isolated rats to the effects of kappa opioids, and that the kappa opioid receptor system is sensitive to social and environmental manipulations after weaning.     

T-cell receptor V beta 8.1 peptide reduces coxsackievirus-induced cardiopathology during murine acquired immunodeficiency syndrome

Infection of people with human immunodeficiency virus (HIV) as well as LP-BM5 infection in mice results in progressive deterioration of the immune system in the majority of untreated hosts. Peptide immunotherapy has been shown to be effective in the stimulation or immunoregulation of T-helper 1 (T(H)1) and T-helper 2 (T(H) 2) response subsets. In murine acquired immunodeficiency syndrome (AIDS), T(H)1 deficiency enables the host to be susceptible to coxsackievirus infection, inducing cardiopathology in a short period. T-cell receptor (TCR) Vbeta8.1 peptide, a 16-mer peptide containing the entire CDR1 segment and part of the FR2 region of human Vbeta8, showed both an immunoregulating and immunostimulating effect in murine AIDS. TCR Vbeta8.1 peptide acts on T cells promoting interleukin-2 production and therefore enhancing a cell-mediated immune response. It retarded development of cardiopathology due to coxsackievirus infection. Retrovirus-infected mice treated with the peptide showed a longer life span than the nontreated, retrovirus-infected animals.     

B vitamins and plasma homocysteine concentrations in an urban and rural area of Costa Rica

OBJECTIVE: We studied the association between total plasma homocysteine (tHcy) concentrations and folate, B(12), and B(6) status in the urban and rural areas of Costa Rica. Subjects and Methods: We determined plasma tHcy concentrations and assessed dietary folate, B(12) and B(6) intake by a food frequency questionnaire in 462 subjects selected by stratified random sampling in the urban and rural areas of Puriscal, Costa Rica. Plasma folate and vitamin B(12) concentrations were measured in women. RESULTS: THcy concentrations were higher (p < 0.01) in the rural compared with the urban area: 12.0 micro mol/L vs. 8.9 micro mol/L in men, and women 7.3 micro mol/L vs. 5.5 micro mol/L in women, respectively. The prevalence of hyperhomocysteinemia (greater than 15.0 micro mol/L) was twice as high in rural compared with urban men (19.8% vs. 10.8%, p = 0.06) and women (6.6% vs. 3.4%, p = 0.26). Most study subjects (98%) had folate intakes that were less than the recommended 400 micro g/day. In women, 31% of those living in the urban area and 40% of those in the rural area had plasma folate concentrations of less than 6.8 nmol/L, an indicator of folate deficiency. In women, age-adjusted mean tHcy concentrations ( micro mol/L) were higher in the lowest compared with highest quintiles for dietary vitamin B(6) (9.9 vs. 5.4, p < 0.05), B(12) (9.2 vs. 4.9, p < 0.01), and folate (7.0 vs. 5.7, p = 0.87). Similar results were found for plasma B(12) (9.9 vs. 5.4, p < 0.01) and folate (10.5 vs. 5.0, p < 0.0001). CONCLUSIONS: Residents of the rural area in Puriscal, Costa Rica have higher plasma concentrations of tHcy and lower intake of B vitamins, particularly in women. Because these characteristics are associated with high risk of cardiovascular disease, the efficacy of food fortification program in rural areas should be carefully addressed.