Road traffic injury risk from alcohol and cannabis use among emergency department patients in Argentina

Objective

To report the risk from alcohol, cannabis, and their combined use for non-fatal road traffic injuries for drivers, passengers, and pedestrians.

Methods

Risk was estimated using the case-crossover method. Participants (N= 306) were injured patients from an emergency department in Mar del Plata, Argentina.

Results

Alcohol use (OR= 6.78, CI 95% 3.75-12.25) as well as combined alcohol and cannabis use (OR= 7.05, CI 95% 1.16-42.73) significantly increased the risk of a road traffic injuries. Alcohol use increased the risk in both, women (OR= 8.87, CI 95% 2.69-29.21) and men (OR= 6.16, CI 95% 3.10-12.23); in those >30 years old (OR= 6.01, CI 95% 2.09-17.24) and those <30 years old (OR= 7.15, CI 95% 3.49-14.65). This last group also had an increased risk after combined alcohol and cannabis use (OR= 7.05, CI 95% 1.16-42.75). Both drivers (OR= 6.40, CI 95% 3.23-12.69) and passengers (OR= 13.83, CI 95% 2.87-66.42) had an increased risk after alcohol consumption.

Conclusions

To our knowledge, these are the first estimates of the risk of having a road traffic injury after alcohol and cannabis consumption in one of the countries of the Southern Cone (Argentina, Chile, and Uruguay). These results highlight the urgent need to implement and enforce comprehensive alcohol control measures. Furthermore, given the global trend towards legalizing cannabis for recreational use, our results could also inform policymakers to enact or amend impaired driving laws.

Efficacy of Brief Intervention for Alcohol Consumption during Pregnancy in Argentinean Women: A Randomized Controlled Trial

INTRODUCTION

Although Brief Intervention (BI) has proven to reduce alcohol consumption during pregnancy in high income countries, there is no evidence from the Southern Cone of America. Thus, we conducted a study to assess BI efficacy among Argentinean pregnant women.

METHOD AND MATERIALS

We collected data on pregnant women receiving prenatal care at the public health system in Mar del Plata, Argentina. Women with less than 26 weeks of gestation (n = 486) were randomized to brief advice (BA) or BI. Three months later they were re-assessed; women with more than 26 weeks of gestation constituted a screening only control group (SC) (n = 154). Self-reported quantity and frequency of alcohol consumption, frequency of binge drinking, and related problems after three months were used as outcomes. We performed generalized estimating equations and clinical significance analyses. Also, we obtained newborn health indicators from the city's health system database to use as objective outcomes. Women who did not participate in any of the three former conditions were randomly selected to constitute a non-screening control group (NSC) (n = 150). We compared objective outcomes among BI, BA, and NSC groups using the Wilcoxon rank test.

RESULTS

In comparison with SC, BI and BA reduced alcohol consumption, without differences between the latter two. Newborns of women who received BI and BA had better health indicators compared with the NSC group.

CONCLUSIONS

performing either a BI or BA reduces alcohol consumption among Argentinean pregnant women and might lead to healthier newborns.

Alcohol industry, corporate social responsibility and country features in Latin America

INTRODUCTION AND AIMS

Research on corporate behaviour can contribute to the understanding of the possible adverse impacts of alcohol-industry corporate social responsibility (CSR) initiatives and their potential influence on policymaking. This study explores the association between alcohol-industry CSR activities and selected country features in Latin America and the Caribbean.

DESIGN AND METHODS

Nine health experts evaluated 148 CSR activities using a standardised protocol; activities were classified into the categories risk management CSR (rmCSR), that is, to avoid/rectify externalities (n = 67), and strategic CSR, that is, to fulfill philanthropic responsibilities (n = 81). We evaluated the associations, separately, between the number of rmCSR and of strategic CSR actions in each country with threats from public health measures (specifically, the level of research into alcohol consumption and harms, the existence of an alcohol surveillance system and the number of governmental alcohol policy actions) and per capita alcohol consumption; we adjusted by economic indices (country income level and the gross domestic product) and population size.

RESULTS

Multivariate analyses showed that the higher the level of alcohol research within a country and its per capita consumption, the more likely rmSCR activities were to occur, independently of the country's economic development or population.

DISCUSSION AND CONCLUSIONS

Results suggest rmSCR actions could be implemented as a way to preserve markets by counteracting scientific evidence about alcohol related harms. This evidence could serve as a starting point to future research, contributing to the understanding of alcohol industry behaviour and the advancement of effective public policies.

Profiles of alcohol use disorder criteria: Help-seeking vs self-achieved remission in Argentinean hospital patients

This study aimed to identify alcohol use disorder (AUD) criteria that better characterized those who seek treatment and those who recover on their own. We gathered data from help-seeking (HS) patients in an alcohol unit and compared them with self-achieved remission (SAR) patients. The best criteria to predict HS were psychological problems due to use, physical problems due to use, repeated attempts or desire to stop using, and not being able to stop drinking. The best criteria to predict SAR were tolerance, craving, hazardous use, much time spent, larger/longer use than intended, and role impairment. We discuss the impact of these results in current efforts to improve the accuracy of AUD diagnosis.

Maternal exposure to organophosphate flame retardants alters locomotor and anxiety-like behavior in male and female adult offspring

Endocrine disrupting chemicals (EDCs) are chemicals found in our environment that interrupt typical endocrine function. Some flame retardants (FRs) are EDCs as shown in their interaction with steroid and nuclear receptors. Humans are consistently exposed to flame retardants as they are used in everyday items such as plastics, clothing, toys, and electronics. Polybrominated diphenyl ethers were used as the major FR until 2004, when they were replaced by organophosphate flame retardants (OPFRs). Previous research in rodent models utilizing a commercial flame retardant mixture containing OPFRs reported alterations in anxiety-like behavior in the elevated plus maze (EPM) for rodents perinatally exposed to OPFRs. In the present study we utilize wild-type mice maternally exposed (gestational day 7 to postnatal day 14) to either an OPFR mixture of tris(1,3-dichloro-2-propyl), triphenyl phosphate, and tricresyl phosphate or a sesame seed oil vehicle. These mice were evaluated for anxiety-like behavior in adulthood on the open field test (OFT) and the light/dark box (LDB) as well as the EPM. Outcomes from the OFT and LDB indicate that males and females maternally exposed to OPFRs exhibit altered locomotor activity. Results of the EPM were sex-specific as we did not observe an effect in females; however, effects in males differed depending on exposure condition. Males maternally exposed to OPFRs exhibited an anxiolytic-like phenotype in contrast to their vehicle counterparts. This effect in perinatally OPFR-exposed males was not due to alterations in locomotor activity. Our research illustrates that there are sex- and exposure-dependent effects of perinatal OPFR exposure on adult locomotor and anxiety-like behaviors in a mouse model.

The Association Between Early Drinking and Dependence Varies by Drinking Context

Evidence regarding the association between early drinking (ED) and later dependence is controversial. It has been alternately hypothesized that ED either plays a causal role in the development of dependence or that it is an early marker of increased psychosocial vulnerabilities. Despite a clear rationale for delaying youth consumption, it is important to discern this relationship. However, most epidemiological evidence comes from individual studies and high-income countries. If there is a causal link between ED and dependence, an association at the aggregate level would be expected. Furthermore, if the link is due to biological mechanisms, the association should be rather invariable regardless of the drinking context, while if the association is due to psychosocial factors, a wider variability is to be expected. We explored whether the association between ED and dependence varied across countries clustered by their shared contextual drinking characteristics. We used data from 169 countries from the Global Information System on Alcohol and Health of the World Health Organization: ED, alcohol dependence, heavy episodic drinking (HED), actual drinkers, and alcohol policy. To cluster countries by their shared drinking characteristics (prevalences of HED and actual drinkers, and alcohol policy), we used, sequentially, two multivariate data reduction techniques: a multiple correspondence analysis (MCA) and a hierarchic classification. To estimate the association between ED and alcohol dependence, beta regressions were performed, and then adjusted by country income-level and repeated by gender. The results indicated four country clusters: primarily abstainers (class 1), low drinking countries (class 2), high drinking countries (class 3), and very high drinking countries (class 4). Positive relationships between ED and alcohol dependence were found for all the countries in the world and for those in classes 1 and 2. No significant relationships were found for class 3 or class 4. These results were similar for males, but not for females, where no significant relationships were found after adjusting for income level. The association between ED and dependence varies according to the drinking context. Our findings either suggest that the ED–dependence association may be due to individual or environmental vulnerabilities that promote consumption outside cultural norms or that, if there is a causal link between ED and dependence, it is strongly moderated by psychosocial characteristics.

C-23 Impact of Social Support on Cognitive Vascular Risk Factors in Latino Older Adults

Objective

Central Americans have a cardiovascular disease (CVD) health advantage, as they are half as likely to carry CVD as European Americans, despite having an equivalent degree of vascular risk factors (VRFs). We examined the impact of social support on this paradox and the relationship to cognitive decrements among Costa Rican older adults.

Methods

We identified predictors of the CVD health advantage (VRFs in the absence of CVD: Heart Attack, MI, Stroke). Hypertension (HTN) and CVD were coded as present or absent based on medical history. Of 315 participants, 146 (46%) had HTN but no CVD, 59 (19%) had CVD, and 110 had neither HTN nor CVD. To estimate ROC curves, we applied canonical discriminant analysis to item groups based on the discipline cluster. The discriminant analysis identified items that maximally differentiated the diagnostic groups in a step-wise fashion.

Results

Social support and social engagement were stronger predictors of the health advantage than subjective memory complaints. Social Support was a reliable indicator of CVD health advantage (accuracy = 93%, sensitivity = 93%, specificity = 89%). Social Engagement was a reliable discriminator of diagnostic groups (accuracy = 84%, sensitivity = 88%, specificity =75%) versus subjective memory complaints (accuracy = 79%, sensitivity of 82%, specificity of 74%).

Conclusion

Our exploratory analyses suggest that social support is an important predictor of living with VRFs but not developing CVD. Current studies are underway to examine the contribution of these risk factors to the development of dementia and cognitive impairment to maximize cost-effective interventions.

C-20 Cardiorespiratory Fitness Predicts Processing Speed Performance in Urban Latin Americans

Objective

There is evidence that cardiorespiratory fitness (CRF) protects against age-related declines in processing speed (PS), but studies investigating older adults living in low and middle-income countries are lacking. We used data from the Epidemiology and Development of Alzheimer’s Disease (EDAD) study to investigate the role of CRF on PS in older Costa Rican adults.

Method

306 community dwelling older adults (mean age = 69) were recruited for a study on cognition and physical fitness. We used a regression model to test the association between CRF and a composite measure of PS (Digit Symbol, Trails A, Block Design, and Stroop Color Naming). Confirmatory factor analysis (CFA) with full information maximum likelihood was conducted in a nested multi-step process on subtest scores. We also compared the strength of the relationship between two measures of CRF: Maximal oxygen uptake (V02 peak) and a latent variable comprised of distance achieved during the 6-minute Walk Test and change in heart rate before and after walking (Modified 6-Minute Walk).

Results

Higher CRF was significantly associated with PS, and the association remained significant after controlling for age and sex (B = 0.21; p < .001). The strength of the relationship between two measures of CRF was very high, suggesting equivalence of these indices.

Conclusions

CRF and PS are clinically meaningful therapeutic targets for future prevention trials in Latin America. The modified 6-Minute Walk is an efficient approximation of the gold standard CRF measurement. The cognitive benefits of CRF should be compared to other lifestyle interventions (e.g., diet) to determine the active components of cognitive improvement.

The Effectiveness of a Brief Intervention for Reducing Adolescent Alcohol Consumption

Introducción: A pesar de que el consumo de alcohol afecta a más de la mitad de los adolescentes, se desconoce la efectividad de intervenciones para evitarlo o reducirlo a nivel local. Este ensayo clínico aleatorizado se propuso determinar la efectividad y significancia clínica de un programa de intervención breve para reducir el consumo de bebidas alcohólicas y problemas relacionados en un contexto educativo de Argentina. Materiales y métodos: Los participantes, estudiantes de educación media seleccionados sistemáticamente (N=167) fueron asignados aleatoriamente a una de tres condiciones: dos grupos control (tamizaje, tamizaje y evaluación) y uno experimental (tamizaje, evaluación e intervención). Con el aval de un Comité de Ética, se implementó un protocolo basado en lineamientos internacionales. Las medidas de efectividad utilizadas fueron disminución de la cantidad habitual, del consumo de alto riesgo, y de los problemas relacionados con el alcohol. Se realizaron análisis descriptivos, regresiones lineales y logísticas, y estimaciones de reducción relativa y absoluta del riesgo y del número de pacientes a tratar para reducir un evento. En la etapa de seguimiento (N=150), la cantidad y el consumo de alcohol de alto riesgo fueron mayores en los grupos control. Resultados: la intervención redujo efectivamente el consumo de alcohol y sus problemas en aproximadamente uno de cada siete adolescentes, con una mínima inversión en entrenamiento y aplicación. Sin embargo, no se encontraron diferencias significativas en los problemas relacionados, que disminuyeron en todas las condiciones. Conclusión: Estudios a largo plazo podrían dilucidar si el cambio se sostiene mayormente en el grupo de intervención.

Consumo excesivo episódico de alcohol: cambio natural en estudiantes universitarios

<p>El consumo abusivo de alcohol puede ser abandonado sin ayuda formal, sin ambargo, la información sobre este hecho es escasa, especialmente en jóvenes que adoptan este tipo de consumo. El objetivo de este estudio es estimar la prevalencia de cambio natural del consumo excesivo episódico de alcohol y explorar su relación con consecuencias adversas del consumo y otras características individuales en jóvenes universitarios. En una muestra aleatoria de 828 estudiantes se evaluó el consumo excesivo episódico pasado/actual, problemas relacionados con el consumo de alcohol, uso de otras sustancias psicoactivas, género y estado civil. La prevalencia de cambio natural fue de 7%. El cambio en el consumo excesivo episódico implicó menor probabilidad de problemas psíquicos, episodios de amnesia anterógrada, lesiones, consumo de otras sustancias y una mayor probabilidad de estar en pareja. Se discute el rol de la severidad de las consecuencias en el cambio natural del consumo, posibles factores de protección y potenciales intervenciones.</p>

Environmental stressors, socioeconomic factors, and alcohol-related problems among Argentinian college students

Introduction. The relationship between alcohol consumption, individual characteristics, and alcohol-related problems may vary according to environmental characteristics in certain populations. Objective. To explore the existence of a hierarchical structure in the links between environmental stressors, individual socioeconomic factors, regular alcohol consumption, use of other substances, and alcohol-related problems in Argentinian university students. Method. With a correlational design and data from a random sample of students from a public university (N = 1578, 58% female), we used a multilevel modeling strategy as follows: alcohol-related problems; regular alcohol consumption (quantity/frequency) as fixed effect, use of other psychoactive substances, sociodemographic factors (individual socioeconomic status, age, and gender); and environmental stressors as random effects (index of overcrowding as an indicator of poverty and reported crime as an indicator of violence in the neighborhood). Results. The rate of overcrowding proved to be the best Level 2 predictor for the alcohol-related problems model. Socioeconomic status, quantity and frequency of consumption, use of other substances, and age directly predicted alcohol-related problems (Level 1). Gender was neither a direct predictor nor a moderator of the links. Discussion and conclusion. At least one environmental stressor (neighborhood poverty) partly explains the variability observed in alcohol-related problems. The quantity and frequency of alcohol consumption and the use of other psychoactive substances were the strongest predictors of alcohol-related problems.

Psychometric Properties of Brief Screening Tests for Alcohol Use Disorders during Pregnancy in Argentina

Background Considering the physical, mental and behavioral problems related to fetal alcohol exposure, prenatal clinical guides suggest a brief evaluation of alcohol consumption during pregnancy to detect alcohol intake and to adjust interventions, if required. Even if any alcohol use should be considered risky during pregnancy, identifying women with alcohol use disorders is important because they could need a more specific intervention than simple advice to abstain. Most screening tests have been developed and validated in male populations and focused on the long-term consequences of heavy alcohol use, so they might be inappropriate to assess consumption in pregnant women. Objective To analyze the internal reliability and validity of the alcohol screening instruments Alcohol Use Disorders Identification Test (AUDIT), Alcohol Use Disorders Identification Test - Consumption (AUDIT-C), Tolerance, Worried, Eye-Opener, Amnesia and Cut-Down (TWEAK), Rapid Alcohol Problems Screen - Quantity Frequency (RAPS-QF) and Tolerance, Annoyed, Cut-Down and Eye-Opener (T-ACE) to identify alcohol use disorders in pregnant women. Methods A total of 641 puerperal women were personally interviewed during the 48 hours after delivery. The receiver operating characteristics (ROC) curves and the sensitivity and specificity of each instrument using different cut-off points were analyzed. Results All instruments showed areas under the ROC curves above 0.80. Larger areas were found for the TWEAK and the AUDIT. The TWEAK, the T-ACE and the AUDIT-C showed higher sensitivity, while the AUDIT and the RAPS-QF showed higher specificity. Reliability (internal consistency) was low for all instruments, improving when optimal cut-off points were used, especially for the AUDIT, the AUDIT-C and the RAPS-QF. Conclusions In other cultural contexts, studies have concluded that T-ACE and TWEAK are the best instruments to assess pregnant women. In contrast, our results evidenced the low reliability of those instruments and a better performance of the AUDIT in this population.

Gender and Alcohol Use Disorders Diagnostic Criteria in Emergency Department Patients of Argentina

BACKGROUND

Alcohol consumption and its related consequences are not equal for women and men, although related studies do not frequently include gender analysis.

OBJECTIVE

Our aim was to characterize differences in endorsement of ICD-10 and DSM 5 alcohol use disorder (AUD) criteria by gender in an Argentinean emergency department population.

METHODS

A probability sample of patients (N = 923) from the largest emergency department in the city of Mar del Plata, Argentina (44% were females, aged 16 to 86, M (SD) = 37.31(15.20) was collected. Using a structured questionnaire, diagnostic criteria for alcohol use disorders, alcohol consumption, and socio-demographic variables were obtained. Bivariate and multivariate analyses were used to assess differences in the endorsement of each diagnostic criterion by gender.

RESULTS

Women were less likely to endorse each of the criteria for each of the diagnostic schemes. Even after controlling alcohol consumption, socio-demographic variables, severity of alcohol use disorders and adjusting for multiple comparisons females had a lower probability than males of endorsing withdrawal and impaired control.

CONCLUSIONS

gender differences in the endorsement of diagnostic criteria for both the DSM 5 and ICD-10 were found. Some differences in endorsement but not all, might be partially explained by alcohol consumption patterns and socio-demographic factors, and same remained after controlling severity of the AUD. Results also suggest a differential functioning of DSM 5 and ICD-10 AUD criteria for women and men.

Registro de información en pacientes con trastornos por uso de alcohol en Mar del Plata, Argentina

Introducción: los datos que se registran sobre el consumo de alcohol son importantes para el diagnóstico y pronóstico de trastornos por uso de alcohol. Objetivo: este estudio descriptivo tuvo como objetivo caracterizar las referencias sobre consumo de alcohol y otras variables relacionadas en los registros hospitalarios de pacientes atendidos en una unidad especializada en alcoholismo de un hospital público de la ciudad de Mar del Plata, Argentina. Metodología: se examinaron los registros de 60 admisiones entre febrero y noviembre del 2011, y se categorizaron extrayendo datos referidos al consumo de alcohol, fuente de la derivación, diagnóstico, tratamiento, internaciones y otras enfermedades, así como aspectos del entorno familiar y socioeconómico. Posteriormente, se realizaron análisis descriptivos teniendo en cuenta el porcentaje de registros en los que se mencionaban estos aspectos. Resultados: si bien el registro de datos referentes al consumo de alcohol fue alto, por lo general fue incompleto. La información registrada denotó que las condiciones biopsicosociales en las que se encuentran estos pacientes son poco favorables para un tratamiento exitoso. Conclusiones: se discute la necesidad de sistematizar la información, por ejemplo, a través de historias clínicas unificadas, junto con formas de prevenir la progresión de trastornos por uso de alcohol.

Epidemiology of alcohol consumption and related problems in Latin American countries: Contributions of psychology

Alcohol consumption is the leading risk factor for morbi-mortality in many Latin American Countries. However, epidemiologic studies are relatively scarce. Among factors such as limited research capacity, disciplinary traditions and an emphasis on psychopathology within the field of psychology, have been postulated to account for this. The aim of this article is to review epidemiologic research on alcohol in Spanish Speaking Latin American Countries, and to measure the contribution of psychology to the field. A systematic search was performed in English and Spanish using regional and international data bases. We identified 269 articles. Most focused on consumption patterns in youth, with samples from a single school and using a variety of measures. With the exception of multinational efforts like Emergency Room Collaborative Alcohol Analysis Project or those supported by World Health Organization/Pan American Health Organization, studies reviewed reflected little cross country collaboration. Mexico accounted for most of the productivity, while many countries had very few or no articles. Most research was performed by health science researchers with a small contribution from psychology, but which increased significantly over time. The results of this review provide a broad identification of patterns regarding epidemiologic research on alcohol, and demonstrate the need for national scientific policies to promote research on public health topics.

Escala de Motivos para Cesar/Reducir el Consumo de Alcohol: propiedades psicométricas

El objetivo de este estudio fue evaluar las propiedades psicométricas de una escala de motivos para cesar o reducir el consumo de alcohol en jóvenes universitarios, en cuanto a dimensionalidad, nivel del ítem, consistencia interna y validez concurrente. Participaron del estudio 377 estudiantes de psicología de la Universidad Nacional de Mar del Plata. Mediante un cuestionario anónimo y confidencial, se indagaron motivos para cesar o reducir el consumo de alcohol con una escala de 20 ítems, desarrollados a partir de respuestas cualitativas. Se incluyeron como criterios de validez la cantidad habitual de alcohol consumida y una regla de motivación al cambio. Se realizaron análisis factoriales exploratorios, confirmatorios, de confiabilidad y bivariados. Los análisis factoriales exploratorios y confirmatorios apuntaron a una estructura de tres dimensiones llamadas: rechazo del alcohol, salud y cambios vitales, y consecuencias severas del consumo de alcohol. Los coeficientes de confiabilidad fueron adecuados. Se encontraron relaciones entre las dos primeras dimensiones y la cantidad de alcohol consumida, y entre la motivación al cambio y la dimensión salud y cambios vitales. Se discute la diferencia entre motivos hipotéticos y reales para el cambio, y el rol de las consecuencias graves del consumo en grupos de mayor ingesta de alcohol.

[Data quality in surveys on alcohol consumption among university students]

Different survey modalities have been developed to assess alcohol consumption and related problems. Research that compares data quality between survey modalities is scarce in Latin America. The aim of this study was to assess data quality in three survey modalities on alcohol consumption: self-administered online, self-administered hard-copy, and face-to-face interviews. Data were obtained from three probabilistic samples of students (n = 60 each) from the National University of Mar del Plata, Argentina, using the same questionnaire. Data quality was measured for each modality by overall response rate, item response rate, and accuracy. Data accuracy was evaluated as the percentage of self-reported binge drinking, positive results on AUDIT, and internal consistency of AUDIT for each modality. The overall and item response rates were lower in the online modality and similar between the other two. No differences were found between modalities in the accuracy of responses.

[Neurological complications of chronic alcoholism: study of 42 observations in Guinea]

Neurologic disorders related to chronic alcoholism in traditional areas of Guinea are frequent, but reports about them are rare. We conducted the first study in Guinea on this subject and retrospectively collected 42 cases of neurologic manifestations related to alcoholism over a 7-year period. The standard findings of the literature were confirmed in our population: peak frequency after the age of 40 years (82.8%) and clear male overrepresentation (M/F sex ratio: 13/1). All the standard signs and symptoms are reported, with a clear predominance of alcoholic polyneuropathy and hepatic encephalopathy. The study of nutritional status by both body mass index (BMI) and the Detsky criteria showed that these patients were severely malnourished. The brain MRI was a crucial contribution for diagnosing the standard central nervous system complications of alcoholism: Gayet Wernicke encephalopathy, Marchiafava-Bignami disease, Korsakoff syndrome, central pontine myelinolysis, and cerebellar degeneration.

[Neurological disorders related to vitamin B12 deficiency in prisons in Guinea: a 22-case study]

Neurological disorders related to vitamin B12 deficiency are common in prisons of tropical Africa. We collected 22 cases (20 men and 2 women). They all showed vitamin B12 deficiency associated with neurological signs that were represented by sclerosis combined with bone marrow (n = 9), peripheral neuropathy (n = 6), cerebellar syndrome (n = 2), a pyramidal syndrome of the lower limbs (n = 4) and optic neuropathy (n = 1). Laboratory tests showed a mean hemoglobin concentration of 7.2 ± 1.5 g/dl, mean 104 ± 28 fl, macrocytic anemia in 10 patients. Biermer's disease was identified in 9 patients, 3 patients showed the syndrome of non dissociation of vitamin B12, a gastrectomy in 2 patients and no etiology was identified in 8 patients.

Delayed catabolism of apoB-48 lipoproteins due to decreased heparan sulfate proteoglycan production in diabetic mice

We used wild-type (WT) mice and mice engineered to express either apoB-100 only (B100 mice) or apoB-48 only (B48 mice) to examine the effects of streptozotocin-induced diabetes (DM) on apoB-100- and apoB-48-containing lipoproteins. Plasma lipids increased with DM in WT mice, and fat tolerance was markedly impaired. Lipoprotein profiles showed increased levels and cholesterol enrichment of VLDL in diabetic B48 mice but not in B100 mice. C apolipoproteins, in particular apoC-I in VLDL, were increased. To investigate the basis of the increase in apoB-48 lipoproteins in streptozotocin-treated animals, we characterized several parameters of lipoprotein metabolism. Triglyceride and apoB production rates were normal, as were plasma lipase activity, VLDL glycosaminoglycan binding, and VLDL lipolysis. However, beta-VLDL clearance decreased due to decreased trapping by the liver. Whereas LRP activity was normal, livers from treated mice incorporated significantly less sulfate into heparan sulfate proteoglycans (HSPG) than did controls. Hepatoma (HepG2) cells and endothelial cells cultured in high glucose also showed decreased sulfate and glucosamine incorporation into HSPG. Western blots of livers from diabetic mice showed a decrease in the HSPG core protein, perlecan. Delayed clearance of postprandial apoB-48-containing lipoproteins in DM appears to be due to decreased hepatic perlecan HSPG.

Atorvastatin and simvastatin have distinct effects on hydroxy methylglutaryl-CoA reductase activity and mRNA abundance in the guinea pig

The effects of atorvastatin and simvastatin on hydroxy methylglutaryl (HMG)-CoA reductase activity and mRNA abundance were studied in guinea pigs randomized to three groups: untreated animals and those treated with 20 mg/kg of atorvastatin or simvastatin. Guinea pigs were fasted for 0, 6, 12, or 18 h in an attempt to remove the drug from their systems. Reductase activity and mRNA levels were analyzed after each time point. Reductase inhibitor treatment resulted in 50-62% lower cholesterol concentrations compared to untreated guinea pigs (P < 0.0001), while plasma triacylglycerol (TAG) concentrations did not differ among groups. Plasma cholesterol and TAG were 50-70% lower after 18 h fasting in the three groups (P < 0.001). In the nonfasting state, simvastatin and atorvastatin treatment did not affect HMG-CoA reductase activity compared with untreated animals. However, after 6 h of fasting, simvastatin-treated guinea pigs had higher HMG-CoA reductase activity than untreated animals (P < 0.01), suggesting that the drug had been removed from the enzyme. In contrast, atorvastatin-treated guinea pigs maintained low enzyme activity even after 18 h of fasting. Further, HMG-CoA reductase mRNA abundance was increased by sevenfold after atorvastatin treatment and by twofold after simvastatin treatment (P < 0.01). These results suggest that simvastatin and atorvastatin have different half-lives, which may affect HMG-CoA reductase mRNA levels. The increase in reductase activity by simvastatin during fasting could be related to an effect of this statin in stabilizing the enzyme. In contrast, atorvastatin, possibly due to its longer half-life, prolonged inhibition of HMG-CoA reductase activity and resulted in a greater increase in mRNA synthesis.

Hypocholesterolemic effects of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors in the guinea pig: atorvastatin versus simvastatin

Male Hartley guinea pigs were fed a hypercholesterolemic diet rich in lauric and myristic acids with 0, 10, or 20 mg/kg of simvastatin or atorvastatin for 21 days. Atorvastatin and simvastatin resulted in a lowering of plasma low-density lipoprotein (LDL) cholesterol in a dose-dependent manner by an average of 48 and 61% with 10 and 20 mg/kg, respectively. Both statins were equally effective in lowering plasma LDL cholesterol and apolipoprotein B (apo-B) levels. Atorvastatin and simvastatin treatments yielded LDL particles that differed in composition from the control. Due to the relevance of LDL oxidation and cholesteryl ester transfer in plasma to the progression of atherosclerosis, these parameters were analyzed after statin treatment. Atorvastatin and simvastatin treatment decreased the susceptibility of LDL particles to oxidation by 95% as determined by the formation of thiobarbituric acid reactive substances. An 80% decrease in the transfer of cholesteryl ester between high-density lipoprotein (HDL) and the apo-B-containing lipoproteins was observed after simvastatin and atorvastatin treatment. In addition, statin effects on plasma LDL transport were studied. Simvastatin- and atorvastatin-treated guinea pigs exhibited 125 and 175% faster LDL fractional catabolic rates, respectively, compared with control animals. No change in LDL apo-B flux was induced by either treatment; however, LDL apo-B pool size was reduced after statin treatment. Hepatic microsomal free cholesterol was lower in the atorvastatin and simvastatin groups. However, only atorvastatin treatment resulted in an 80% decrease of acyl-CoA:cholesterol acyltransferase activity (P < 0.001). In summary, atorvastatin and simvastatin had similar LDL cholesterol lowering properties, but these drugs modified LDL transport and hepatic cholesterol metabolism differently.

Hamsters and guinea pigs differ in their plasma lipoprotein cholesterol distribution when fed diets varying in animal protein, soluble fiber, or cholesterol content

There were two objectives to these studies: 1) to compare the lipoprotein cholesterol distribution in two animal models in response to different dietary treatments and 2) to assess whether the hypercholesterolemia induced by high cholesterol intake could be reversed by consumption of vegetable-protein and/or dietary fiber. Guinea pigs, which carry the majority of plasma cholesterol in LDL, and hamsters, with a higher distribution of cholesterol in HDL, were evaluated in three different studies. In Study 1, animals were fed semi-purified diets for 4 wk with proportions of 60:40, 20:80 or 0:100 (w/w) of casein/ soybean protein. Hamsters and guinea pigs that consumed 100% soybean protein had lower plasma total cholesterol (TC) than those fed diets containing casein (P < 0.01). In Study 2, three doses of dietary pectin (2.7, 5.4, or 10.7 g/100g) added in place of cellulose were tested. Intake of 10.7 g/100 g pectin resulted in the lowest plasma TC concentrations for both species (P < 0.01). Although the TC lowering was similar in studies 1 and 2, the lipoprotein cholesterol distribution differed. Whereas the differences in plasma cholesterol were in LDL in guinea pigs, hamsters exhibited differences in both non-HDL and HDL cholesterol. In study 3, animals were fed 100% soybean protein, 10.7 g/100 g pectin, and three doses of dietary cholesterol: 0.04, 0.08, or 0.16 g/100 g, which is equivalent to 300, 600, or 1,200 mg/d in humans. Guinea pigs and hamsters had the highest plasma LDL and hepatic cholesterol concentrations when they consumed 0.16 g/100 g of cholesterol (P < 0.01). However, intake of 0.08 g/100 g of cholesterol resulted in lower plasma LDL cholesterol concentrations than did consuming high animal protein (60:40 casein/ soy) or low soluble fiber (2.7 g/100 g). Relatively high levels of dietary cholesterol combined with vegetable protein and soluble fiber resulted in desirable lipoprotein profiles in animal models that significantly differ in their lipoprotein cholesterol distribution.

Hypolipidemic mechanisms of pectin and psyllium in guinea pigs fed high fat-sucrose diets: alterations on hepatic cholesterol metabolism

Studies were conducted to determine whether pectin (PE) or psyllium (PSY) could reverse the high plasma cholesterol and triacylglycerol (TAG) concentrations induced by high fat (HF) or high sucrose (HS) diets and which are the mechanisms involved. Male guinea pigs were fed either a low fat (LF) or a HF diet with 80% of the carbohydrate energy derived from sucrose. Cellulose was used as control. Plasma LDL cholesterol, TAG, apolipoprotein B, and hepatic cholesteryl ester were lower in guinea pigs fed PE and PSY compared to the control group (P < 0.03). In addition, a 45% higher number of hepatic apoB/E receptors was observed by PE and PSY intake. Hepatic ACAT, HMG-CoA reductase, and cholesterol 7alpha-hydroxylase (C7H) activities were higher in the HF compared to the LF groups (P < 0.01). PSY intake with HF resulted in up-regulation of C7H and HMG-CoA reductase activities (P < 0.05). Additional studies measuring the effects of PE and PSY on low density lipoprotein (LDL) transport and very low density lipoprotein (VLDL) secretion were conducted in the HF groups. ApoB secretion was reduced by pectin and psyllium (P < 0.01) intake while LDL fractional catabolic rates were 100% faster in guinea pigs fed PE or PSY. In these studies the extent of the hypolipidemic response was specific to each fiber type and associated with the amount of sucrose. In addition, PSY altered the activity of hepatic enzymes of cholesterol homeostasis in the HF group. These additional effects of PSY might explain the more dramatic changes in plasma lipid levels associated with PSY consumption.

Regulation of apolipoprotein B-containing lipoproteins by dietary soluble fiber in guinea pigs

Dietary soluble-fiber sources such as pectin, guar gum, or psyllium decrease plasma concentrations of low-density-lipoprotein (LDL) cholesterol in guinea pigs by distinct mechanisms, including increases in LDL apolipoprotein (apo) B turnover and/or decreases in LDL apo B flux (J Lipid Res 1995; 36:2394-404). The present studies were undertaken to test whether changes in the rates of very-low-density lipoprotein (VLDL) apo B secretion, VLDL conversion to LDL, and hepatic uptake of VLDL were related to the cholesterol-lowering actions of these soluble fibers. Guinea pigs were fed (by wt) 12.5% pectin, 12.5% guar gum, 7.5% psyllium, or a control diet containing cellulose as the fiber source. Plasma cholesterol concentrations were significantly lower in guinea pigs fed pectin, guar gum, and psyllium by 42%, 46%, and 35%, respectively (P < 0.001), compared with those animals fed the control diet, whereas plasma triacylglycerol concentrations were lower only with guar gum intake. The secretion rate of triacylglycerol, determined after Triton was injected to block VLDL catabolism, was not different among dietary treatment groups whereas the secretion rate of apo B was lower with pectin, guar gum, and psyllium intakes (P < 0.01). In addition, pectin, guar gum, and psyllium significantly altered the composition of newly secreted VLDLs by increasing the number of triacylglycerol and phospholipid molecules in the secreted lipoprotein, indicating the presence of larger nascent VLDLs. In contrast, the average particle diameter of mature VLDLs as determined by electron microscopy was smaller in the dietary soluble-fiber groups in the following order: pectin < psyllium < guar gum. Plasma lecithin-cholesteryl acyltransferase and cholesteryl ester transfer protein activities were lower with intake of pectin, guar gum, and psyllium (P < 0.01). Injection of radiolabeled lipoproteins indicated that pectin, guar gum, and psyllium intakes resulted in more rapid VLDL and LDL apo B turnover and lower LDL apo B flux in guinea pigs fed guar gum and psyllium. These results suggest that the secretion rate of apo B, compositional changes in lipoproteins occurring in the intravascular compartment, and up-regulation of LDL receptors-associated with faster LDL apo B turnover rates-are secondary metabolic responses induced by dietary fiber that contribute to the lowering of plasma cholesterol concentrations.

Hypocholesterolemic actions of atorvastatin are associated with alterations on hepatic cholesterol metabolism and lipoprotein composition in the guinea pig

Guinea pigs were fed 15% (w/W) fat, high in lauric and myristic acids, a diet known to produce hypercholesterolemia in these animals. The diet was given alone or in combination with four doses of atorvastatin equivalent to 1, 3, 10, and 20 mg/kg per day. Atorvastatin reduced plasma LDL cholesterol concentrations by 46, 50, 53, and 70%, respectively (P < 0.001). Plasma apoB concentrations were reduced by atorvastatin (P < 0.001) and compositional changes occurred in VLDL and LDL with reductions of the relative proportion of cholesteryl ester and increases in triacylglycerol. A reduction in hepatic cholesteryl ester (66%) was observed only with the highest atorvastatin dose (20 mg/kg per day) while microsomal cholesterol was reduced by 30% with 3-20 mg/kg per day. Hepatic ACAT activity was down-regulated and apoB/E receptor number was increased by atorvastatin. In contrast, HMG-CoA reductase activity and cholesterol 7 alpha-hydroxylase were not affected by the drug. VLDL apoB secretion rates were decreased by atorvastatin treatment 59 and 76% with 3 and 20 mg/kg per day, respectively. Nascent VLDL particles were larger after drug treatment, showing an increased number in triacylglycerol molecules. These results support the hypothesis that the plasma LDL lowering induced by atorvastatin is due to a decreased secretion of apoB in combination with an increase of hepatic apoB/E receptors.

Dietary carbohydrate type and fat amount alter VLDL and LDL metabolism in guinea pigs

The effects of low/high fat diets and simple/complex carbohydrate intake on specific aspects of plasma VLDL and LDL metabolism were evaluated. Guinea pigs were fed for 4 wk two different fat/carbohydrate concentrations: 2.5/58 (g/100 g) or 25/29 (g/100 g) with either sucrose or cornstarch as the sole carbohydrate source. Intake of high fat diets resulted in higher plasma cholesterol (P < 0.001), whereas sucrose intake resulted in higher plasma triacyglycerol (TAG) concentrations (P < 0.03). Intake of starch increased apolipoprotein (apo) B secretion rates (P < 0.001), and nascent VLDL were smaller and contained less TAG/apo B than particles from the sucrose-fed group (P < 0.01). Guinea pigs fed the starch diets had higher plasma VLDL apo B flux and faster VLDL apo B clearance than those fed sucrose diets (P < 0.01). In addition, more rapid VLDL removal from plasma in guinea pigs fed complex carbohydrate/high fat diets was associated with less conversion of VLDL to LDL and lower plasma cholesterol concentrations compared with the high fat/sucrose group (P < 0.01). Low fat compared with high fat intake resulted in 60% more rapid plasma LDL apo B fractional catabolic rates (FCR). The LDL apo B fractional catabolic rate of all dietary groups was inversely correlated with plasma cholesterol concentrations (r = -0.83, P < 0.001). These results demonstrate that in guinea pigs, low fat diets decrease plasma LDL cholesterol concentrations by increasing LDL turnover rates, and complex carbohydrates reduce plasma TAG by affecting the composition of nascent VLDL particles and by increasing VLDL apo B catabolism.