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Christof Kessler

Publications and source records attributed to Christof Kessler.

12 recordsLinked to original sources

Association between alcohol consumption and subclinical carotid atherosclerosis: the Study of Health in Pomerania.

BACKGROUND AND PURPOSE: Epidemiologic studies have shown a J-shaped association between alcohol consumption and vascular diseases. However, only few studies have reported on the association between alcohol intake and subclinical atherosclerosis. The aim of the study was to investigate the relation between alcohol intake and carotid intima-media thickness (IMT) in participants of the population-based Study of Health in Pomerania. METHODS: In 1230 men and 1190 women, the mean IMT of the right and left common carotid arteries was measured by B-mode ultrasonography. Alcohol consumption was assessed with a computer-assisted face-to-face interview. RESULTS: In men, carotid IMT as a function of alcohol intake was depicted as a J-shaped curve with a nadir for the alcohol intake category of 61 to 80 g/d. Linear regression models controlled for age, diabetes, systolic blood pressure, leisure time physical activity, food frequency patterns, smoking status, and education revealed a significant inverse association between IMT and alcohol intake < or =80 g/d in men (beta=-0.009, P<0.02), which became insignificant after further controlling for HDL cholesterol and fibrinogen (beta=-0.007, P=NS). In women, neither a J-shaped relation nor significant differences in IMT between the drinking and nondrinking groups were found. CONCLUSIONS: Alcohol consumption is inversely correlated with carotid IMT in men but not in women. However, the total daily level of alcohol intake that shows a maximum protective effect against atherosclerosis is above the threshold where severe alcohol related comorbidity and organ damage have been reported.

Adult↗

Relation of parity with common carotid intima-media thickness among women of the Study of Health in Pomerania.

BACKGROUND AND PURPOSE: Metabolic and hormonal changes associated with pregnancy and childbirth are assumed to contribute to the development of cardiovascular disease among women. We analyzed the association of parity with common carotid intima-media thickness (IMT), which has a predictive value of subsequent myocardial infarction and stroke. METHODS: The Study of Health in Pomerania (SHIP), an epidemiological study of the general population in the northeast of Germany, included 1195 women aged 45 to 79 years. Mean and maximum far-wall IMT of the common carotid arteries were assessed by high-resolution ultrasound. All women were comprehensively characterized as to their reproductive history as well as to socioeconomic, behavioral, and biological risk factors. RESULTS: There was a U-shaped association between the number of children (from 0 to > or =4) and mean and maximum IMT. Nulliparous women had the highest age-adjusted mean (0.81 mm [95% CI, 0.78 to 0.84]) and maximum IMT (1.04 mm [95% CI, 1.00 to 1.09]), and women with single parity the lowest (mean IMT, 0.73 [95% CI, 0.72 to 0.74]; maximum IMT, 0.91 mm [95% CI, 0.89 to 0.93]; P<0.001 versus nulliparity for both parameters). Stepwise multivariate adjustment for socioeconomic factors, lifestyle variables, and biological variables attenuated the magnitude of this association yet significance remained. CONCLUSIONS: Nulliparity and higher number of children are associated with increased carotid IMT. These findings add support to the hypothesis of a link between the reproductive history of women and cardiovascular disease.

Aged↗

Hepatic steatosis is associated with an increased risk of carotid atherosclerosis.

AIM: Although an association between hepatic steatosis and vascular risk factors has been described, direct relationships between fatty liver and atherosclerosis have not yet been investigated. The aim of the present study has been to investigate those relationships. METHODS: The Study of Health in Pomerania examined a random population sample aged between 20 and 79 years. A study population of 4 222 subjects without hepatitis B and C infections and without liver cirrhosis was available for the present analysis. Hepatic steatosis was defined sonographically and intima-media thickness (IMT) as well as plaque prevalence were estimated by carotid ultrasound. RESULTS: The prevalence rate of hepatic steatosis was 29.9%. Among subjects aged > or =45 years, an association between hepatic steatosis and IMT of the carotid arteries was found in bivariate analysis, but not after adjustment for atherosclerotic risk factors. Individuals with fatty liver had more often carotid plaques than persons without fatty liver (plaque prevalence rate 76.8% vs 66.6%; P<0.001). This association persisted after adjustment for confounding factors and was predominantly present in subjects with no to mild alcohol consumption. CONCLUSION: There is an independent association between hepatic steatosis and carotid atherosclerotic plaques. Metabolic changes due to nonalcoholic fatty liver disease may explain this relationship.

Adult↗

Proteomic identification of the involvement of the mitochondrial rieske protein in epilepsy.

PURPOSE: Kindled seizures are widely used to model epileptogenesis, but the molecular mechanisms underlying the attainment of kindling status are largely unknown. Recently we showed that achievement of kindling status in the Sprague-Dawley rat is associated with a critical developmental interval of 25 +/- 1 days; the identification of this long, well-defined developmental interval for inducing kindling status makes possible a dissection of the cellular and genetic events underlying this phenomenon and its relation to normal and pathologic brain function. METHODS: By using proteomics on cerebral tissue from our new rat kindling model, we undertook a global analysis of protein expression in kindled animals. Some of the identified proteins were further investigated by using immunohistochemistry. RESULTS: We report the identification of a modified variant of the Rieske iron-sulfur protein, a component of the mitochondrial cytochrome bc1 complex, whose isoelectric point is shifted toward more alkaline values in the hippocampus of kindled rats. By immunohistochemistry, the Rieske protein is well expressed in the hippocampus, except in the CA1 subfield, an area of selective vulnerability to seizures in humans and animal models. We also noted an asymmetric, selective expression of the Rieske protein in the subgranular neurons of the dorsal dentate gyrus, a region implicated in neurogenesis. CONCLUSIONS: These results indicate that the Rieske protein may play a role in the response of neurons to seizure activity and could give important new insights into the molecular pathogenesis of epilepsy.

Animals↗

Asymptomatic carotid atherosclerosis is associated with circulating chlamydia pneumoniae DNA in younger normotensive subjects in a general population survey.

OBJECTIVE: Chlamydia pneumoniae infection has been associated with atherosclerosis, but serodiagnosis is unreliable in predicting vascular infection. Direct detection of circulating chlamydial DNA in peripheral blood mononuclear cells (PBMCs) was thus evaluated as a marker for cardiovascular risk in a general population survey using the common carotid intima-media thickness (IMT) as surrogate marker of asymptomatic atherosclerosis. METHODS AND RESULTS: C pneumoniae DNA in PBMCs was determined by nested polymerase chain reaction and associated with IMT for 1032 healthy participants of a general population survey who were within the highest or lowest IMT distribution quartile. C pneumoniae DNA was more prevalent in those with increased IMT (13.4% versus 10.7%), but this was not significant in univariate and of borderline significance in multivariate analysis. Testing for potential effect modifications by known strong determinants of an increased IMT in group interaction analysis revealed an independent association between C pneumoniae DNA and IMT in normotensive subjects (odds ratio [OR], 2.06; 95% CI, 1.05 to 4.03; P=0.04) and in those <70 years old (OR, 1.84; 95% CI, 1.06 to 3.19; P=0.03). CONCLUSIONS: Asymptomatic atherosclerosis is associated with circulating C pneumoniae DNA independently of classical cardiovascular risk factors in normotensive subjects and those <70 years old. C pneumoniae has been implicated in atherogenesis. We determined the association of chlamydial DNA in peripheral blood mononuclear cells with the carotid intima-media thickness from 1032 healthy subjects from a general population survey. A stratified group interaction analysis revealed an independent association in normotensive subjects and those <70 years old.

Adult↗

Gender differences in the relationship between periodontal disease, tooth loss, and atherosclerosis.

BACKGROUND AND PURPOSE: Males carry a disproportionate burden of cardiovascular disease. Because males also bear a higher burden of periodontal disease, we investigated the existence of gender differences in the postulated relationship between periodontal infections, tooth loss, and subclinical atherosclerosis. METHODS: A total of 1710 randomly enrolled participants between the ages of 45 and 75 with no history of myocardial infarction or stroke received a clinical periodontal examination, carotid scan using high-resolution B-mode ultrasound, and extensive measurements for conventional cardiovascular risk factors (age, education, smoking, alcohol, body mass index, diabetes, systolic blood pressure, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and triglycerides) as well as markers of healthy lifestyle and social network. RESULTS: In both genders, measures of current and long-term periodontitis worsened as tooth loss increased. In males but not females, an approximately 10% difference in carotid artery plaque prevalence was observed between the lowest and highest tertiles of tooth loss (P<0.05) and long-term periodontitis (P=0.05) after multivariate adjustment. Similar patterns were observed for intima-media thickness. The influence of gender on carotid artery plaque prevalence was most evident among the younger age group (<59 years). Between genders, carotid plaque prevalence differed by 10%, 15%, and 25% across increasing levels of tooth loss, and by 5%, 15%, and 25% across increasing levels of long-term periodontitis. CONCLUSIONS: Our data suggest that tooth loss and long-term periodontitis are related to subclinical atherosclerosis in men but not women. Gender variations in cardiovascular morbidity or mortality may be explained partly by the differential contributions of novel risk factors across genders.

Aged↗

Sex and the risk of restless legs syndrome in the general population.

BACKGROUND: Restless legs syndrome (RLS) is characterized by the desire to move the limbs associated with paresthesias of the legs, a motor restlessness, an intensification of symptoms at rest with relief by activity, and a worsening of symptoms in the evening or at night. Population-based studies are rare, and risk factors in the general population are not known. METHODS: Cross-sectional survey with face-to-face interviews and physical examination among 4310 participants in the Study of Health in Pomerania in northeastern Germany. Participants were aged 20 to 79 years and were randomly selected from population registers. Restless legs syndrome was assessed with standardized, validated questions addressing the 4 minimal criteria for RLS as defined by the International Restless Legs Syndrome Study Group. RESULTS: The overall prevalence of RLS was 10.6%, increasing with age, and women were twice as often affected as men. While nulliparous women had prevalences similar to those among men up to age 64 years, the risk of RLS increased gradually for women with 1 child (odds ratio, 1.98; 95% confidence interval, 1.25-3.13), 2 children (odds ratio, 3.04; 95% confidence interval, 2.11-4.40), and 3 or more children (odds ratio, 3.57; 95% confidence interval, 2.30-5.55). Subjects with RLS had significantly lower quality-of-life scores than those without the syndrome. CONCLUSIONS: Restless legs syndrome is a common disease in the general population, affecting women more often than men. It is associated with reduced quality of life in cross-sectional analysis. Parity is a major factor in explaining the sex difference and may guide further clarification of the etiology of the disease.

Adult↗

Association between high serum ferritin levels and carotid atherosclerosis in the study of health in Pomerania (SHIP).

BACKGROUND AND PURPOSE: Several studies have provided evidence for a relationship between body iron load and cardiovascular disease. We analyzed the association of serum ferritin levels with carotid atherosclerosis. METHODS: We assessed intima-media thickness and plaque prevalence in the carotid arteries by high-resolution ultrasound among 2443 participants (1200 women; age, 45 to 79 years) in the Study of Health in Pomerania (SHIP), a population-based study in northeast Germany. RESULTS: In multivariate analysis, serum ferritin levels were not independently associated with carotid intima-media thickness among women or men. In contrast, the relationship between serum ferritin levels and carotid plaque prevalence was significant among men (odds ratio per 1-SD increase of serum ferritin levels, 1.33; 95% confidence interval, 1.08 to 1.44) yet not among women (odds ratio, 1.29; 95% confidence interval, 0.98 to 1.75). However, both men and women showed a dose-response relation between serum ferritin levels and carotid atherosclerosis in which higher serum ferritin levels were associated with greater odds ratios for carotid plaque prevalence. Additionally, there was an interaction of serum ferritin levels with low-density lipoprotein (LDL) cholesterol (P=0.039) among men in which the association of serum ferritin levels with carotid plaque prevalence became stronger with increasing LDL cholesterol levels. CONCLUSIONS: Our study identified a relationship between serum ferritin levels and carotid atherosclerosis that was potentiated by LDL cholesterol. This relationship adds support to the hypothesis of a link between iron and cardiovascular disease.

Aged↗

Echo-enhanced duplex sonography of extracranial vertebral arteries.

We sought to investigate the potential benefit in examining extracranial vertebral arteries (ExVA) with an echo contrast agent. A total of 26 patients with insufficiently assessable ExVA underwent extracranial duplex sonography without and with an echo contrast medium. All examinations were recorded and analysed independently by two experienced sonographers. Interrater agreement was fair in assessment of B-mode quality, colour-coding, blooming artefacts, change of vmax, good to very good in all other rated categories. Using an echo contrast medium reduced overall inassessable ExVA by 48% and 36% according to the two raters, respectively. After contrast enhancement, diagnosis was clarified in ExVA formerly inassessable for hypoplasia in 60% vs. 56%, extracranial occlusion in 67% vs. 56% and resistance signal in 63% vs. 45%, respectively. Application of an echo contrast agent leads to clarification of ExVA sonographic diagnosis in approximately one third of poorly examinable patients (35% and 30%, respectively), and contributes in ruling out extracranial occlusion, hypoplasia and resistance signal.

Arterial Occlusive Diseases↗

Thyroid function and carotid wall thickness.

Decreased serum TSH levels predict vascular mortality in older people. There is a need to investigate mechanisms that could explain this association. This study was designed to investigate the relationship between thyroid function and the carotid intima-media thickness (IMT). The Study of Health in Pomerania is a population-based survey in Germany. Data from 2086 individuals at least 45 yr old with carotid ultrasound and without known thyroid disorders were analyzed. Twenty-nine participants (1.4%) had elevated serum TSH levels, 300 (14.4%) had decreased serum TSH levels, and 12 (0.6%) participants were hyperthyroid. A linear relationship between thyroid function and IMT was found. The highest IMT values were observed in participants with hyperthyroidism, the lowest in subjects with elevated serum TSH levels (P < 0.01). A multivariable regression analysis identified thyroid function as an independent risk factor for increased IMT. Other risk factors for increased IMT included male gender, advanced age, diabetes mellitus, current smoking, and the use of antihypertensive medication; increased pulse pressure, serum low-density cholesterol, and total cholesterol/high-density lipoprotein ratio; as well as a decreased heart rate and a positive history of myocardial infarction. We conclude that there is an independent association between thyroid function and the IMT of the carotid artery.

Carotid Arteries↗

Affective blindsight: intact fear conditioning to a visual cue in a cortically blind patient.

Blindsight refers to remarkable residual visual abilities of patients with damage to the primary visual cortex (V1). Recent studies revealed that such residual abilities do not apply only to relatively simple object discriminations, but that these patients can also differentially categorize and respond to emotionally salient stimuli. The current study reports on a case of intact fear conditioning to a visual cue in a male patient with complete bilateral cortical blindness. The patient was admitted to the stroke unit of the neurological department because of complete loss of vision. Both CT and structural MRI scans confirmed lesions in both territories of the posterior cerebral artery. No visual evoked potentials could be detected confirming complete cortical blindness. During fear conditioning, a visual cue predicted the occurrence of an aversive electric shock. Acoustic startle probes were presented during and between the conditioned stimuli. Relative to the control condition, startle reflexes were substantially potentiated when elicited in the presence of the conditioned stimuli. No such potentiation was observed prior to conditioning. These data suggest that fear learning to visual cues does not require a cortical representation of the conditioned stimulus in the primary sensory cortex and that subcortical pathways are sufficient to activate the fear module in humans.

Aged↗

Association between behavior-dependent cardiovascular risk factors and asymptomatic carotid atherosclerosis in a general population.

BACKGROUND AND PURPOSE: Physical inactivity and unfavorable dietary and lifestyle patterns are related to cardiovascular disease and premature death. Their relationship to atherosclerosis of the carotid arteries and subsequent stroke is unclear. The objective of this study was to investigate the association between those behavioral cardiovascular risk factors and asymptomatic atherosclerosis of the carotid arteries in a population of former East Germany. METHODS: The Study of Health in Pomerania (SHIP) is a cross-sectional survey in northeast Germany. In 1632 individuals aged 45 to 70 years, high-resolution B-mode ultrasound was used to assess the mean intima-media thickness of the right and left common carotid arteries. Carotid plaques and stenosis were recorded. Physical activity, dietary patterns, and cardiovascular risk factors were assessed in interviews with the use of standardized scales. Physically active participants with optimal dietary patterns were classified in the optimal lifestyle group, and those inactive with unfavorable diet were classified in the unfavorable group. RESULTS: After adjustment for sex and age, significant decreasing trends were found for both intima-media thickness and severe asymptomatic atherosclerosis from unfavorable to optimal lifestyle patterns in never smokers but not in smokers. Regression analysis revealed an increased risk of severe asymptomatic atherosclerosis in subjects with an unfavorable lifestyle pattern compared with those with an optimal pattern (odds ratio 2.68; 95% CI, 1.13 to 6.37), following a significant linear trend. CONCLUSIONS: Physical activity and optimal diet are associated with reduced risk of early atherosclerosis in subjects who never smoked, while no benefit of an otherwise optimal lifestyle is observed in smokers.

Aged↗