Relationship between Lipid profile and Carotid artery parameters among Mgbuoba community dwellers, Port Harcourt, Nigeria: A random survey

Abstract

Background: An important variable in apparently normal individuals that may affect findings on duplex carotid scan is their lipid numbers. In developing  countries like Nigeria, routine health checks are not upheld and where available are not exhaustive. Carotid intima media thickness (cIMT) and cholesterol  have been implicated as risk factors for stroke. Studies in diseased states have shown an association between lipid numbers and carotid IMT.  Asymptomatic apparently healthy subjects are rarely targets for carotid evaluations except in limited circumstances. Some apparently healthy individuals  may already have abnormal lipid numbers; thus this study seeks to assess the association between carotid parameters and lipid profile amongst  apparently healthy subjects.

Method: This cross sectional, community-based study, assessed the extra-cranial common and internal carotid artery variables in 74 randomly selected  apparently healthy individuals, from Mgbuoba community, Port Harcourt Rivers State. Four extra cranial vessels: left common carotid (LCC) and right  common carotid (RCC) left internal carotid (LIC) and right internal carotid (RIC) were evaluated using a predefined protocol to assess parameters such as  vessel diameters, peak systolic velocities (PSV), end diastolic velocities (EDV), resistivity index (RI) and intimal media thickness (cIMT). Fasting venous  blood samples were collected and analysed using a Colour Spectrophotometer for Total Cholesterol (TC), High Density Lipoprotein (HDL), Low Density  Lipoprotein (LDL) and Triglyceride (TG). The mean values for the common carotid artery variables, Total Cholesterol (TC), Low density Lipoprotein (LDL),  High Density Lipoprotein (HDL) and Triglycerides (TG).

Result: Data was collected on Excel spread sheet and analyzed using SPSS 23 statistical software package. Seventy-four (74) subjects comprising 30 (41%)  males and 44(59%) females respectively were studied. Their mean age ± SD was 38.60 ±12.56yrs. Mean Systolic blood ±SD and diastolic blood  pressure±SD were 122.94 ± 12.64mmHg and 75.41 ± 9.20 mmHg respectively. There was negative correlation between total cholesterol and LCC PSV  (-.31,.03), negative correlation between HDL and LCC diameter (-.29,.03) and positive correlation between LDL cholesterol and IMT (.30,.04). On the RCC  there was a negative correlation between HDL and RI (-.38,.02). on the LIC there was negative correlation between TG (-0.33,.05)). Plaques were identified  in 2 with only mild stenosis.

Conclusion: The impact of cholesterol on the carotid artery parameters is not just in symptomatic or diseased states but also  in apparently normal individuals. It is an important area and more studies are encouraged. It will be pertinent to explore this in a larger study population.  An important area would be the impact of HDL on vessel distensibility.