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C Tzourio

Publications and source records attributed to C Tzourio.

At least 19 recordsLinked to original sources
PubMed2006

Cross-sectional association between homocysteine and motor function in the elderly.

OBJECTIVE: To determine if there is a cross-sectional association between homocysteine (tHcy) level and measures of gait and balance in elderly subjects. METHODS: We studied 3,609 noninstitutionalized subjects aged 65 to 85 years from the Dijon (France) center of the Three-City Study. tHcy concentration was measured from fasting blood samples. Motor function was assessed by measuring walking speed and by using a modified version of the Tinetti scale. RESULTS: After adjustment for confounders, mean maximum walking speed (MWS) decreased with increasing tHcy levels (p = 0.001). The odds ratio (OR) (95% CI) for having a MWS below the 40th percentile was 1.9 (1.4 to 2.5) in subjects with tHcy levels in the upper quintile compared with those in the lowest quintile. Compared with subjects in the lowest tHcy quintile, the OR for having a modified Tinetti score below 16 ranged from 1.0 (0.8 to 1.4) in the second quintile to 1.9 (1.3 to 2.6) in the upper quintile (p < 0.0001). CONCLUSIONS: Elevated homocysteine concentrations are associated with worse motor performances in the elderly. These findings support the hypothesis of a vascular contribution to motor function.

Age Factors↗
PubMed2005

APOE genotype, cholesterol level, lipid-lowering treatment, and dementia: the Three-City Study.

OBJECTIVE: To examine the association of plasma cholesterol levels, lipid-lowering agent (LLA) intake, and APOE genotype with dementia prevalence. METHODS: The Three-City Study is a population-based cohort of 9,294 subjects selected from the electoral rolls of three French cities (Bordeaux, Dijon, Montpellier). Baseline examination included extensive assessment of exposure to vascular risk factors (including cholesterol levels and LLA use [statin or fibrate]) and clinical diagnosis of dementia. RESULTS: Two percent of participants were demented at baseline. Overall 32.4% of participants had hyperlipidemia, and 15.6% were prescribed statins and 13.7% fibrates. After adjusting for age, gender, education level, and study center, the odds ratio (OR) for dementia was observed to be lower among LLA users (OR = 0.61, 95% CI = 0.41 to 0.91) compared with subjects taking no LLAs. There was no differential effect between statin and fibrate users. The odds for dementia were increased in subjects with hyperlipidemia (OR = 1.43, 95% CI = 1.03 to 1.99). Further adjustment for potential confounders did not modify these associations. In addition, the association between LLA intake and dementia was not modified by APOE genotype, whereas hyperlipidemia was significantly associated with increased dementia prevalence only in non-epsilon4 carriers and non-Alzheimer disease cases. Finally, in participants taking LLAs, the odds for dementia were decreased only in those having normal lipid levels. CONCLUSIONS: This observational study provides further evidence that lipid-lowering agents are associated with decreased risk of dementia, whereas hyperlipidemia is associated with increased odds for non-Alzheimer-disease-type dementia. These effects appear to be independent of all major potential confounders.

Aged↗
PubMed2004

Early epidural blood patch in spontaneous intracranial hypotension.

Thirty patients with a typical orthostatic headache were treated by early lumbar epidural blood patch (EBP) without previously performing lumbar puncture or identifying a CSF leak and with or without typical MRI changes. A complete cure was obtained in 77% of patients after one (57%) or two (20%) EBPs. Spontaneous intracranial hypotension with typical orthostatic headache can be diagnosed without lumbar puncture and can be cured by early EBP in a majority of patients.

Adolescent↗
PubMed2004

[Towards a prevention of dementia?].

Many studies have shown that high blood pressure and, to a lesser extent, other vascular risk factors could be the target of interventions aiming to reduce the incidence of dementia. Two large controlled trials have demonstrated that blood pressure lowering drugs have a significant effect on the risk of dementia including Alzheimer's disease. On another hand, large epidemiological studies have shown associations between different vascular factors and dementia. Overall, these data suggest that interventions aiming to reduce the level of vascular risk factors might prevent dementia. The expected benefit of these interventions could be estimated from data provided by epidemiological studies, but large population-based controlled studies are needed to demonstrate the efficacy of preventive interventions.

Age Factors↗
PubMed2004

Teaching of neuroepidemiology in Europe: time for action.

Many epidemiological and clinical studies in Europe, especially in Eastern Europe and countries in transition, are of poor methodological quality because of lack of background knowledge in clinical epidemiology methods and study designs. The only way to improve the quality of epidemiological studies is to provide adequate undergraduate and/or postgraduate education for the health professionals and allied health professions. To facilitate this process, the European Federation of Neurological Societies (EFNS) Task Force on teaching of clinical epidemiology in Europe was set up in October 2000. Based on analyses of the current teaching and research activities in neuroepidemiology in Europe, this paper describes the Task Force recommendations aimed to improve these activities.

Education, Medical↗
PubMed2004

Association of polymorphisms in the Tau and Saitohin genes with Parkinson's disease.

BACKGROUND: The Saitohin gene has recently been identified in intron 9 of the Tau gene. Because an association between Parkinson's disease and Tau has been described, Saitohin represents a candidate gene for Parkinson's disease. OBJECTIVE: To test these two genes for their association with Parkinson's disease in a large community based case-control study. RESULTS: Cases (n = 208) were more often homozygotes for the Tau H1 haplotype than controls (n = 483; odds ratio (OR) = 1.71 (95% confidence interval, 1.20 to 2.43); p = 0.003), and the saitohin Q allele was in complete linkage disequilibrium with the H1 haplotype. This association was stronger among cases with Parkinson's disease onset below 65 years (< or =65 years: OR = 2.52 (1.49 to 4.25); p<0.001) than among those with older onset (>65 years: OR = 1.20 (0.73 to 1.98); p<0.47). CONCLUSIONS: The data suggest that there is a functional polymorphism at this locus involved in Parkinson's disease.

Aged↗
PubMed2003

Effects of a perindopril-based blood pressure-lowering regimen on disability and dependency in 6105 patients with cerebrovascular disease: a randomized controlled trial.

BACKGROUND AND PURPOSE: We sought to quantify the effects of blood pressure lowering on long-term disability and dependency among patients with cerebrovascular disease. METHODS: We performed a randomized, double-blind, placebo-controlled trial. A total of 6105 participants with a history of stroke or transient ischemic attack in the past 5 years were recruited from 172 hospital outpatient clinics in 10 countries. Subjects were randomly assigned to the following groups: active treatment (angiotensin-converting enzyme inhibitor perindopril [4 mg/d] for all patients, with the diuretic indapamide added at the discretion of treating physicians) or matching placebo(s). Measurements were disability (defined as a Barthel Index score < or =99/100) and dependency (a positive response to the following question: "In the last 2 weeks has the patient required regular help with everyday activities?"). RESULTS: The median duration of follow-up was 4 years. At the last available assessment, 19% of the active treatment group and 22% of the placebo group were disabled (adjusted odds ratio, 0.76; 95% CI, 0.65 to 0.89; P<0.001). Twelve percent of the active treatment group and 14% of the placebo group were dependent (adjusted odds ratio, 0.84; 95% CI, 0.71 to 0.99; P=0.04). The effects of treatment appeared to be mediated primarily through the prevention of disability and dependency associated with recurrent stroke. Four-year treatment with the study drug regimen would be expected to result in the avoidance of 1 case of long-term disability for every 30 (95% CI, 19 to 79) patients. CONCLUSIONS: Among individuals with cerebrovascular disease, a perindopril-based blood pressure-lowering regimen not only reduced the risk of stroke and major vascular events but also substantially reduced the risks of associated long-term disability and dependency.

Activities of Daily Living↗
PubMed2003

Influence of education on the relationship between white matter lesions and cognition.

OBJECTIVE: To test the hypothesis that education level modulates the effects of cerebral white matter hyperintensities (WMH) on cognition in a large population-based study. METHODS: A total of 845 elderly subjects aged 64 to 76 years who enrolled in a longitudinal study on cognitive decline and vascular aging had an MRI examination. Cognitive functions were assessed by Mini-Mental State Examination, Trail Making Test Part B, Digit Symbol Substitution Test of the Wechsler Adult Intelligence Scale-Revised, Finger Tapping Test, Word Fluency Test, and Raven Progressive Matrix. MRI scans were interpreted visually using a standardized scale for rating WMH. RESULTS: Severe WMH were present in 17% of the participants who had lower performances on tests involving attention tasks. In participants with a lower level of education, presence of severe WMH was significantly associated with lower cognitive performances. This was found for all cognitive tests. Conversely, in participants with a high level of education, there was no significant association between severity of WMH and level of cognitive functions. CONCLUSION: Education modulates the consequences of WMH on cognition. Participants with a high level of education were protected against the cognitive deterioration related to vascular insults of the brain.

Aged↗
PubMed2003

Relationship between migraine, blood pressure and carotid thickness. A population-based study in the elderly.

The relationship between migraine and blood pressure is controversial. We studied the association between migraine and blood pressure in a population-based sample of elderly patients. Participants were 1373 subjects 59-71 years of age. Lifetime migraine was diagnosed according to the International Headache Society criteria by a headache specialist. Blood pressure was measured as well as the carotid intima-media thickness (IMT) which is a good marker of the long-term exposure to high blood pressure. Migraine during life was diagnosed in 140 participants. Mean systolic blood pressure was lower in subjects with migraine than in those without headache (128 mmHg vs. 137 mmHg). There was a significant trend of decreasing frequency of migraine with increasing blood pressure and also with increasing IMT. In this study, migraine was associated with lower levels of blood pressure and with smaller values of carotid wall thickness.

Aged↗
PubMed2003

Lay versus expert interviewers for the diagnosis of migraine in a large sample of elderly people.

OBJECTIVE: To determine the agreement between lay interviewers and experts in the diagnosis of migraine by questionnaire. SUBJECTS: A population based sample of 1188 individuals aged 64 to 73 years. METHODS: Participants who declared that they had recurrent headaches (n = 238) answered a structured questionnaire by lay interviewers with special training in migraine. A migraine expert subsequently interviewed all the headache sufferers using the same questionnaire. Migraine was defined according to the International Headache Society criteria. RESULTS: In comparison with the expert, the diagnosis derived by the lay interviewers had high values for specificity (97%) and positive predictive value (86%), and a low sensitivity (50%) and negative predictive value (57%). Agreement between the expert and the lay interviewers was low, with a kappa value of 0.36 (95% confidence interval 0.26 to 0.47). The most serious discrepancies concerned the duration of attacks, the worsening of headaches by physical activity, the presence of nausea or vomiting, and the unilaterality of headaches. As a result, the lifetime prevalence of migraine headaches was greatly underestimated by lay interviewers (6.5%) in comparison with the expert (11.1%). CONCLUSIONS: A low level of agreement between lay interviewers and a headache expert in the diagnosis of migraine headaches by structured questionnaire may result in a substantial underestimation of migraine prevalence.

Aged↗
PubMed2002

Migraine and the risk of cervical artery dissection: a case-control study.

The association between migraine and cervical artery dissection (CAD) was explored in a hospital-based case-control study. Migraine was present in 49.1% (23/47) of patients with CAD and in 21% (11/52) of patients hospitalized for a cerebral ischemic event not related to a CAD (adjusted odds ratio = 3.6; 1.5 to 8.6, p = 0.005). This result supports the hypothesis that an underlying arterial wall disease could be a predisposing condition for migraine.

Adult↗
PubMed2001

Association between migraine and endothelin type A receptor (ETA -231 A/G) gene polymorphism.

BACKGROUND: Previous studies have described an association between migraine and endothelin, a potent vasoconstrictor. OBJECTIVE: To test the association between migraine and gene polymorphisms of the endothelin system. METHODS: A population-based study of elderly individuals (n = 1,188) in Nantes (western France) was conducted. Lifetime migraine was defined according to the International Headache Society criteria, after an interview with a headache specialist. Five polymorphisms in genes encoding endothelin 1, endothelin type A (ET(A)), and type B receptors were determined in more than 90% of the sample. RESULTS Migraine was diagnosed in 140 participants (11.9%). The ETA (-231 A/G) polymorphism was the only polymorphism significantly associated with migraine. There was a trend of decreasing prevalence of migraine with number of copies of the G allele (AA genotype: 15.7% of participants with migraine, AG: 9.7%, GG: 2.9%; p < 0.001). Carrying the G allele was associated with a sex- and age-adjusted odds ratio of 0.50 (95% CI, 0.34 to 0.74). The association was observed in both sexes and was stronger in participants with a family history of severe headaches than in those without. CONCLUSIONS: A variant of the ET(A) receptor gene modulates the risk for migraine. These results offer new insights into the pathophysiology of the vascular component of migraine.

Age Factors↗
PubMed2001

Longitudinal study of blood pressure and white matter hyperintensities: the EVA MRI Cohort.

OBJECTIVE: To investigate the relationship between baseline hypertension and severity of white matter hyperintensities (WMH) at 4-year follow-up in a sample of subjects aged 59 to 71 years old at entry. METHODS: Subjects were participants in the Epidemiology of Vascular Ageing study, a longitudinal study on vascular aging and cognitive decline. At 4-year follow-up, 845 subjects had a cerebral MRI. MRI examinations were read by a single rater to determine the severity of WMH, ranging from absent to severe. Hypertension at each wave of the study was defined as systolic blood pressure > or =160 mm Hg, diastolic blood pressure > or =95 mm Hg, or use of antihypertensive medication. RESULTS: Hypertension at baseline was significantly associated with an increased risk of having severe WMH at 4-year follow-up. When taking into account both blood pressure levels and antihypertensive drug intake, analysis showed that the risk of having severe WMH was significantly reduced in subjects with normal blood pressure taking antihypertensive medication compared with those with high blood pressure taking antihypertensive agents. Cross-sectional relationships between hypertension and WMH at 4-year follow-up showed that the frequency of severe WMH was significantly higher in people who were hypertensive at both baseline and 4-year follow-up than those who were hypertensive only at 4-year follow-up. CONCLUSIONS: Hypertension is a major risk factor for severe WMH. Subjects taking antihypertensive drugs and who have controlled blood pressure had a reduced risk of severe WMH. Longitudinal studies are needed to investigate whether reduction of the development of WMH, by treatment and prevention of hypertension, might reduce the subsequent risk of cognitive deterioration or stroke.

Aged↗
PubMed2001

Aldosterone synthase (CYP11B2) gene polymorphism and cerebral white matter hyperintensities.

The association between aldosterone synthase (CYP11B2) gene polymorphism and white matter hyperintensities seen on cerebral MRI was studied in a population-based sample of 829 individuals aged 63 to 75 years. The T allele was associated with the risk of severe white matter hyperintensities. Compared with the CC genotype, the adjusted OR for severe white matter hyperintensities was 4.61 (95% CI, 1.46 to 14.55) for the TT genotype and 2.45 (95% CI, 0.81 to 7.46) for the TC genotype in men. This association was independent of hypertension.

Aged↗
PubMed2001

Low cerebral blood flow velocity and risk of white matter hyperintensities.

Cerebral blood flow velocity (CBF-V) measured by transcranial doppler was assessed in 628 elderly individuals who had cerebral magnetic resonance imaging performed as part of a population-based study on vascular aging. Cerebral white matter hyperintensities (WMHs) were associated with low CBF-V, such as the adjusted odds ratios of severe WMHs from highest (referent) to lowest quartile of mean CBF-V were 1.0, 1.7, 3.7, and 4.3 (p = 0.001). Further, CBF-V was found to be a stronger risk factor for WMHs than high blood pressure. These findings suggest that the assessment of CBF-V might be a powerful tool in future studies on WMHs.

Aged↗
PubMed2000

Arterial wall properties in carotid artery dissection: an ultrasound study.

BACKGROUND: Cervical artery dissection is often attributed to an underlying arteriopathy related to a generalized extracellular matrix defect. OBJECTIVE: The authors compared the hemodynamic and morphologic properties of the carotid artery, as assessed noninvasively by ultrasonography, in patients with spontaneous internal carotid artery dissection (ICAD) and control subjects. METHOD: Twenty-six patients who experienced ICAD more than 6 months before evaluation were compared with 26 controls matched for age, sex, and height. Cases and controls had ultrasound measurement of common carotid artery diameter and diameter change during the cardiac cycle, bulbar and suprabulbar internal carotid artery diameters, and common carotid artery intima-media thickness. The unaffected carotid artery in cases was compared with the carotid artery of the same side in controls. RESULTS: Common carotid artery relative diameter change was significantly higher in cases than controls, whereas other measurements were not significantly different between the groups. In multivariate analyses, the highest tertile of common carotid artery relative diameter change was associated with the risk of ICAD (OR, 10.0; 95% CI, 1.8 to 54.2; p = 0.002) CONCLUSION: An underlying arteriopathy, presumably related to an extracellular matrix defect, may be present in patients with spontaneous ICAD.

Adult↗
PubMed2000

Parkinson's disease, smoking, and family history. EUROPARKINSON Study Group.

There is growing evidence that both genetic and environmental factors play a role in the etiology of Parkinson's disease (PD). The hypothesis of an interaction between genetic and environmental risk factors has been little explored, and never using a population-based case-control study design. Our objective was to investigate the possible interaction between smoking and family history in the etiology of PD, as part of a collaborative population-based case-control study. We included 149 nondemented PD patients ascertained in three European prevalence surveys using a two-phase design. Each patient was matched by age (+/-2 years), gender, and center to three controls drawn from the same populations (n=375). Presence of PD among first-degree relatives and smoking history were assessed through an interview for 127 cases and 306 controls. In the overall sample we found suggestive evidence that family history and ever-smoking interact in determining the risk of PD (P=0.09), with individuals exposed to both risk factors having the highest risk (OR=10.0; 95% CI=2.0-49.6). Analyses were repeated after stratification into two age-groups (cutoff: 75 years). In older patients, the joint exposure to both risk factors was associated with a significant increase in the risk of PD (OR=17.6; 95% CI=1.9-160.5). Among younger subjects, the OR for joint exposure was not significant. In conclusion, our findings suggest that smoking and family history interact synergistically on a multiplicative scale in determining the risk of PD in individuals older than 75 years.

Age of Onset↗