Prevalence of Carotid Artery Disease and Risk Factors in Asymptomatic Thai Population using Carotid Duplex Ultrasonography at the Check-up Clinic, Health Promotion Center at Bangkok Hospital

Abstract

OBJECTIVE:To examine the prevalence of carotid artery disease and to determine risk factors for carotid duplex abnormalities among asymptomatic Thai subjects.MATERIALS AND METHODS:The cross-sectional observation study was conducted in a sample of patients (Thai population) who took an annual health check-up at the Bangkok Medical Center (BMC) over a 10 month period from June 1, 2011 to March 31, 2012. A total of 2,105 subjects were enrolled and underwent a carotid duplex examination using the standard procedure. The results from the carotid duplex ultrasonography and risk factors that contribute to carotid artery abnormalities were recorded and analyzed using a multiple logistic regression method and a prevalence rate ratio.RESULTS:The study enrolled 2,105 Thai participants aged 25-79 years old with a mean of age of 54 ± 10.4 years. The population was equally divided by gender, and 44% of subjects were current smokers and 25% of the patients were overweight. Approximately 30.5% of participants had hypertension (HT) and 9.3% had diabetes mellitus (DM). Abnormal carotid duplex examinations were found in 912 cases accounting for 45.7% of the participants.Atheromatous plaque and thickening of the intimal media thickness was observed in 784 cases (37.2%) and 314 cases (14.9%) respectively. Internal carotid stenosis results were detected including 11 mild, 9 moderate and 2 severe stenotic cases; however, no carotid occlusion reported. Underlying HT and DM were related to abnormal duplex results. Factors including increasing age (p < 0.001), male gender (odds ratio (OR) 1.5, 95% confidence interval (CI) 1.2-2.0), and HT associated (OR 2.4, 95% CI 1.8-3.1) were associated with carotid atherosclerotic disease observed by the duplex examination.CONCLUSION:The prevalence of atherosclerotic carotid arteries detected by duplex ultrasonography was approximately 45% among asymptomatic Thai population who took an annual health check at the BMC. Atheromatous plaque is the most common finding and significant (moderate to severe) internal carotid artery (ICA) stenosis was observed in 0.5% of participants. Factors including age, male gender, DM, and HT were associated with atherosclerotic carotid disease. High fasting plasma glucose (FPG) and low-density lipoprotein (LDL) were also related to abnormal carotid duplex results. The carotid duplex examination provided health information to the participants to help control risk factors and to raise awareness of cerebrovascular disease.