Prevalence and Correlates of Intracranial Atherosclerotic Disease Among Community-Dwelling Older Adults of Amerindian Ancestry. The Three Villages Study.

BACKGROUND: Knowledge on the prevalence and correlates of intracranial atherosclerotic disease (ICAD) is limited. We aimed to assess prevalence, clinical and neuroimaging correlates of ICAD in a cohort of older adults of Amerindian ancestry. METHODS: The study included 581 community-dwellers aged ≥60 years (mean age 71 ± 8.4 years; 57% women) living in rural Ecuadorian villages. ICAD was identified by means of CT determinations of carotid siphon calcifications (CSC) or MRA findings of significant stenosis of intracranial arteries. Fully-adjusted logistic regression models were fitted with biomarkers of ICAD as the dependent variables. RESULTS: A total of 205 (35%) of 581 participants had ICAD, including 185 with high calcium content in the carotid siphons and 40 with significant stenosis of at least one intracranial artery (20 subjects had both biomarkers). Increasing age, high fasting blood glucose, >10 enlarged basal ganglia-perivascular spaces and non-lacunar strokes were associated with high calcium content in the carotid siphons. In contrast, male gender, moderate-to-severe white matter hyperintensities, lacunar and non-lacunar strokes were associated with significant stenosis of intracranial arteries. Stroke was more common among subjects with any biomarker of ICAD than in those with no biomarkers (29% versus 9%, p < 0.001). Significant stenosis of intracranial arteries was more often associated with stroke than high calcium content in the carotid siphons, suggesting that CSC are more likely an ICAD biomarker than causally related to stroke. CONCLUSIONS: ICAD prevalence in Amerindians is high, and is significantly associated with stroke. CSC and significant stenosis of intracranial arteries may represent different phenotypes of ICAD.

Intracranial Atherosclerosis And The Earlobe Crease (Frank's Sign). A Population Study / Aterosclerosis Intracraneal Y Pliegue Auricular (Signo De Frank). Estudio Poblacional

ABSTRACT Background: The earlobe crease (ELC) has been linked to coronary artery disease and other vascular conditions, but there is no information on its association with intracranial atherosclerosis. Objective: This study aimed to assess the association between high calcium content in the carotid siphons (as a surrogate of intracranial atherosclerosis) and ELC in community-dwelling adults living in rural Ecuador. Methods: Atahualpa residents aged ≥40 years underwent head CT to estimate calcium content in the carotid siphons, and visual inspection of both earlobes to evaluate the presence of ELC. The association between both variables was assessed by logistic regression models, after adjusting for demographics and cardiovascular risk factors. Results: Of 651 enrolled individuals (mean age: 59.7±12.8 years; 54% women), 225 (35%) had ELC, and 143 (22%) had high calcium content in the carotid siphons. Univariate logistic regression showed a borderline (non-significant) association between high calcium content in the carotid siphons and ELC presence (OR: 1.44; 95% C.I.: 0.99 - 2.12; p=0.057), which disappeared when age (OR: 0.98; 95% C.I.: 0.65 - 1.48; p=0.923) and other covariables (OR: 0.97; 95% C.I.: 0.63 - 1.49; p=0.890) were added to the model. Conclusion: This population study shows no association between high calcium content in the carotid siphons and ELC presence.

RESUMEN Antecedentes: El pliegue auricular se ha relacionado con enfermedad coronaria y otras patologías vasculares, pero no hay información sobre su asociación con aterosclerosis intracraneal. Objetivo: Este estudio tuvo como objetivo evaluar la asociación entre el contenido de calcio en los sifones carotideos (como un sustituto de aterosclerosis intracraneal) y el pliegue auricular en adultos viven en zonas rurales de Ecuador. Métodos: Los residentes de Atahualpa de 40 años o más fueron sometidos a TC de cerebro para estimar el contenido de calcio en los sifones carotideos. Además, ambas orejas fueron examinadas para detectar la presencia de pliegues auriculares. La asociación entre ambas variables se evaluó mediante modelos de regresión logística, ajustados por factores demográficos y de riesgo cardiovascular. Resultados: De 651 individuos enrolados (edad media: 59,7±12,8 años, 54% mujeres), 225 (35%) tuvieron pliegues auriculares y 143 (22%) tuvieron alto contenido de calcio en los sifones carotideos. La regresión logística univariada mostró una asociación limítrofe (no significativa) entre el contenido de calcio en los sifones carotideos y la presencia de pliegue auricular (OR: 1.44, 95%IC: 0.99 - 2.12, p=0.057), que desapareció cuando la edad (OR: 0.98; 95% I.C.: 0,65 - 1,48; p=0,923) y otras covariables (OR: 0,97; 95% I.C.: 0,63 - 1,49; p=0,890) fueron agregadas al modelo estadístico. Conclusión: El presente estudio no mostró asociación entre el contenido de calcio en los sifones carotídeos y la presencia de pliegue auricular.

Distribution of Cervicocephalic Atherosclerotic Lesions and Their Correlation with Cardiovascular Risk Factors in a Population of Amerindians. The Atahualpa Project.

BACKGROUND: No information is available on the distribution of cervicocephalic atherosclerosis in Amerindians. We aimed to assess the distribution of these lesions and their correlation with cardiovascular risk factors in Amerindians living in rural Ecuador. METHODS: Atahualpa residents aged ≥40years underwent head CT for assessment of carotid siphon calcifications (CSC) and sonographic examination for measurement of the carotid intima media thickness (cIMT). CSC were used as a surrogate of intracranial atherosclerosis and the cIMT as a surrogate of extracranial atherosclerosis. Linear regression and multinomial logistic regression models were fitted to assess the association between cIMT and CSC, and to evaluate differences in risk factors across individuals with atherosclerosis involving both arterial beds when compared with those with extra- or intracranial atherosclerosis alone, or no atherosclerosis. RESULTS: Of 590 participants, 145 had high calcium content in the carotid siphons and 87 had a cIMT >1mm (25% versus 15%, P < .001). Thirty-eight (7%) individuals had atherosclerosis at both vascular beds, 107 (18%) had intracranial atherosclerosis, and 49 (8%) had extracranial atherosclerosis alone. The cIMT and CSC were independently associated (P = .008). When compared with participants without atherosclerosis, those with atherosclerosis at both vascular beds were older, more often male, hypertensive and diabetic. Subjects with intracranial atherosclerosis alone were older, and those with extracranial atherosclerosis alone reported less physical activity than those without atherosclerosis. CONCLUSION: Intracranial atherosclerosis is more common than extracranial atherosclerosis in Amerindians. Traditional risk factors only explain a minority of cases of cervicocephalic atherosclerosis in this population.

Enlarged perivascular spaces in the basal ganglia are independently associated with intracranial atherosclerosis in the elderly.

BACKGROUND AND AIMS: Enlarged basal ganglia perivascular spaces (BG-PVS) are a marker of cerebral small vessel disease (SVD). The association between enlarged BG-PVS and atherosclerosis has been explored, but knowledge is limited to extracranial vessels. We aimed to assess whether enlarged BG-PVS correlate with carotid siphon calcifications (CSC), used as a surrogate of intracranial atherosclerosis. METHODS: Atahualpa residents aged ≥60 years underwent head computed tomography (CT) for assessment of CSC, and brain magnetic resonance imaging (MRI) for evaluation of BG-PVS and other imaging markers of SVD. We evaluated the association between BG-PVS and CSC severity (dependent variable) using regression models adjusted for demographics and cardiovascular risk factors. RESULTS: Of 437 candidates, 354 (81%) were included. Grade 1 CSC were observed in 131 (37%), Grade 2 in 99 (28%), Grade 3 in 92 (26%), and Grade 4 in 32 (9%) subjects. MRI showed >10 enlarged BG-PVS in 97 (27%) participants, moderate-to-severe white matter hyperintensities in 81 (23%), lacunar infarcts in 39 (11%), and deep microbleeds in 28 (8%). Fully-adjusted models showed a significant association between enlarged BG-PVS and CSC severity. Individuals with Grade 4 CSC have 3 times de odds of having enlarged BG-PVS than those with Grade 1 CSC. Enlarged BG-PVS were observed in 20% versus 41% of individuals with Grade 1 and Grade 4 CSC, respectively. CONCLUSIONS: Enlarged BG-PVS often coexist with CSC, suggesting that a common pathogenetic mechanism may explain the occurrence of both conditions.

The Role of Brachial Pulse Pressure as an Indicator of Intracranial Atherosclerosis: The Atahualpa Project.

INTRODUCTION: Carotid siphon calcifications (CSC) are an important imaging marker of systemic atherosclerosis. Routine assessment of asymptomatic CSC may allow the implementation of intervention strategies before catastrophic cerebrovascular events occur. AIM: To assess whether brachial PP determinations might independently predicts the presence and severity of CSC in community-dwelling adults. METHODS: All Atahualpa residents aged ≥40 years were invited for the practice of a non-enhanced CT scan of the head, and those who signed the informed consent and had no contraindications for this exam were enrolled. The brachial PP was calculated by subtracting the mean diastolic pressure from the mean systolic pressure obtained from three different readings with individuals in the sitting position. RESULTS: Of 830 eligible candidates, 663 (80%) were included. The mean brachial PP was 56.4 ± 19.9 mmHg; 182 persons (27.4%) had PP levels >65 mmHg. CT revealed Grade 1 CSC in 356 (54%), Grade 2 in 141 (21%), Grade 3 in 128 (19%), and Grade 4 in 38 (6%) subjects. Predictive margins of PP (delta method) were significantly lower in individuals with Grade 1 CSC than in the other groups. In the best adjusted linear model, PP levels increased up to 11.7 mmHg as the severity of CSC increased (ß 11.71; 95% C.I. 5.36-18.08: p < 0.001). CONCLUSION: This study provides evidence on the relationship between brachial PP levels and intracranial atherosclerosis. Calculation of the PP may be used for detecting candidates for CT screening, reducing costs during population-based surveys, particularly in remote areas.

Inverse relationship between the body mass index and severity of carotid siphon calcifications (another obesity paradox): Results from the Atahualpa Project.

BACKGROUND AND AIMS: The importance of the obesity paradox in the intracranial vasculature has not been explored. We assessed whether the body mass index (BMI) correlates with severity of carotid siphon calcifications (CSC) in community-dwelling adults. METHODS: Using a population-based study design, Atahualpa residents aged ≥40 years underwent head computed tomography (CT) for assessment of CSC. We evaluated the association between BMI and severity of CSC (dependent variable) using regression models adjusted for demographics and cardiovascular risk factors. RESULTS: Of 830 people enrolled in the Atahualpa Project, 651 (78%) were included. Mean BMI was 27.3 ± 5 kg/m2, with 39% being overweight and 27% obese. CT revealed high calcium content in the carotid siphon in 25% participants. In an adjusted model, individuals with normal weight had a trend for presenting with more severe CSC than those overweight (p = 0.06), and those ones had significantly more severe CSC than obese participants (p = 0.04). Predictive margins of BMI were higher in individuals with low calcium content in the carotid siphon. A contour plot with Shepard interpolation showed that the paradox disappeared in older individuals and in those with severe obesity, irrespective of age. CONCLUSIONS: BMI inversely associates with severity of CSC. This paradox is relevant in younger individuals and in those without severe obesity, irrespective of age.