Carotid intima media thickness as a measure of cardiovascular disease burden in nigerian africans with hypertension and diabetes mellitus

Carotid Intima-Media Thickness and Its Correlation With Echocardiographic Left Ventricular Function and Geometry in Hypertensive Individuals: A Cross-Sectional Study

Background It is important to consider left ventricular hypertrophy (LVH) and carotid intima-media thickness (CIMT) in assessing hypertensive patients' global cardiovascular risk profile, as LVH and arterial wall changes occur concurrently. This study aimed to assess the relationship between CIMT and left ventricular geometry and function in hypertensive patients. Methodology This cross-sectional study included 200 hypertensive individuals and sought to correlate their CIMT with left ventricular geometry and function in Lagos University Teaching Hospital. Hypertension was defined as blood pressure ≥140/90 mmHg or on treatment for hypertension presenting at the outpatient clinics. Patients who satisfied the inclusion criteria were recruited. Abnormal CIMT was defined as >0.9 mm. Patients' demographic data were obtained in addition to general characteristics, physical examination, transthoracic echocardiography, and CIMT. The statistical relationship between CIMT and left ventricular geometry and function was obtained and analyzed. Results Normal geometry and LVH were observed in 50.5% and 15.5%, respectively. Left ventricular geometry was associated with abnormal CIMT (χ2 = 31.688, p < 0.001). Furthermore, the mean left ventricular mass index was statistically different between abnormal and normal CIMT (97.84 ± 30.5 vs. 80.75 ± 15.6; p < 0.001). Regarding left ventricular function, there was no significant difference in E-point septal separation, left ventricular fractional shortening, and left ventricular ejection fraction in abnormal versus normal CIMT groups. However, there was a significant association of CIMT with grades of diastolic dysfunction (χ2 = 7.069, p = 0.029). Additionally, individual parameters of diastolic dysfunction such as left atrial volume index and septal mitral were significantly different (p < 0.001). Conclusions There was an association between age, left ventricular geometry, diastolic function, and CIMT in hypertensive individuals. Therefore, it is beneficial to evaluate CIMT and for these patients to receive more targeted blood pressure control which may reduce the risk of cardiovascular diseases.

Ultra sonographic indices of the carotid artery in healthy adult population of southwest, Nigeria: a cross-sectional study

Introduction

atherosclerosis develops insidiously, offering time and opportunities for early detection. Screening for subclinical atherosclerosis via structural wall changes and flow velocities among apparently healthy adults using carotid ultrasonography may help its early detection, offer timely intervention and reduce morbidity and mortality.

Methods

a cross-sectional study of 100 participants with a mean age of 56.1 ± 6.9 years, were enrolled from a community population. Both carotid arteries were examined for plaques, carotid intima-media thickness (CIMT), and flow velocities - peak systolic velocity (PSV), end-diastolic velocity (EDV), pulsatility index (PI), and resistive index (RI) using 4-12MHz linear array transducer. Visceral obesity, serum lipids, and blood glucose were also evaluated and correlated with ultrasound findings.

Results

the mean CIMT was 0.07 ± 0.02cm and 15% of the participants had increased CIMT. Statistically significance but weak correlations were observed between CIMT and FBG (r = 0.199, p = 0.047), EDV (r =0.204, p= 0.041), PI (r = -0.287, p = 0.004) and RI (r = -0.268, p =0.007). Statistically significance with modest correlations were observed between EDV and PSV (r = 0.48, p = 0.000), PI (r = -0.635, p = 0.000) and RI (r = -0.637, p = 0.000). The PI and RI showed strong correlation with statistical significance (r= 0.972, p = 0.000).

Conclusion

statistical significance in the flow velocities, derived flow indices and increased CIMT may be an early indication of subclinical atherosclerosis. Therefore, ultrasonography may facilitate its early detection and possible prevention of complications.

Regional and demographic variations of Carotid artery Intima and Media Thickness (CIMT): A Systematic review and meta-analysis

Background and objective

Carotid artery intima media thickness (CIMT) is a strong predictor of Coronary Heart Disease (CHD) and independent phenotype of early atherosclerosis. The global variation of CIMT and its demographic association is yet unclear. We evaluated regional variations of CIMT based on WHO regions and assessed the differences by age and sex.

Methods

A systematic search was conducted on studies published between 1980 January up to December 2020. PubMed, Oxford Medicine Online, EBSCO, Taylor & Francis, Oxford University Press and Embase data bases were used for searching. Supplementary searches were conducted on the Web of Science and Google Scholar. Grey literature was searched in “Open Grey” website. The two major criteria used were “adults” and “carotid intima media”. The search strategy for PubMed was created first and then adapted for the Oxford Medicine Online, EBSCO, Taylor & Francis, Oxford University Press and Embase databases. Covidence software (Veritas Health Innovation, Melbourne, Australia; http://www.covidence.org) was used to manage the study selection process. Meta-analyses were done using the random-effects model. An I2 ≥ 50% or p< 0:05 were considered to indicate significant heterogeneity.

Results

Of 2847 potential articles, 46 eligible articles were included in the review contributing data for 49 381 individuals (mean age: 55.6 years, male: 55.8%). The pooled mean CIMT for the non-CHD group was 0.65mm (95%CI: 0.62–0.69). There was a significant difference in the mean CIMT between regions (p = 0.04). Countries in the African (0.72mm), American (0.71mm) and European (0.71mm) regions had a higher pooled mean CIMT compared to those in the South East Asian (0.62mm), West Pacific (0.60mm) and Eastern Mediterranean (0.60mm) regions. Males had a higher pooled mean CIMT of 0.06mm than females in the non CHD group (p = 0.001); there were also regional differences. The CHD group had a significantly higher mean CIMT than the non-CHD group (difference = 0.23mm, p = 0.001) with regional variations. Carotid artery segment-specific-CIMT variations are present in this population. Older persons and those having CHD group had significantly thicker CIMTs.

Conclusions

CIMT varies according to region, age, sex and whether a person having CHD. There are significant regional differences of mean CIMT between CHD and non-CHD groups. Segment specific CIMT variations exist among regions. There is an association between CHD and CIMT values.

An Overview of Vascular Dysfunction and Determinants: The Case of Children of African Ancestry

The balance between dilatory and constrictive factors is important as it keeps blood vessels in a homeostatic state. However, altered physiological processes as a result of obesity, hypertension, oxidative stress, and other cardiovascular risk factors may lead to vascular damage, causing an imbalance of vasoactive factors. Over time, the sustained imbalance of these vasoactive factors may lead to vascular dysfunction, which can be assessed by non-invasive methods, such as flow-mediated dilation, pulse wave velocity, flow-mediated slowing, retinal vessel analysis, peripheral vascular reactivity, and carotid intima-media thickness assessment. Although there is increasing prevalence of cardiovascular risk factors (obesity and hypertension) in children in sub-Saharan Africa, little is known about how this may affect vascular function. This review focuses on vasoactive factors implicated in vascular (dys)function, highlighting the determinants and consequences of vascular dysfunction. It further describes the non-invasive methods used for vascular (dys)function assessments and, last, describes the impact of cardiovascular risk factors on vascular dysfunction in children of African ancestry.

Intima-media thickness of femoral arteries and carotids among an adult hypertensive Nigerian population: A case-control study to assess their use as surrogate markers of atherosclerosis

Background:

Increased intima-media thickness (IMT) is an established and important surrogate marker for atherosclerosis. Intima-media thickening in the femoral arteries occur earlier and reflect the true extent of generalized atherosclerosis better than in the carotids. Aims: To study the ultrasound-detected morphological changes in the common femoral versus carotid artery wall.

Patients and Methods:

A case-control study design was used, with 61 adult hypertensive as cases and 61 age-, sex- and BMI-matched normotensive as controls. Variables were participants' characteristics, cardiovascular risk factors, and ultrasonographically evaluated IMT of the carotid and femoral arteries.

Results:

A total of 122 participants were studied. The mean femoral IMT in hypertensives and controls on the right and left was 0.63 ± 0.07mm vs. 0.52 ± 0.06mm [P < 0.0001] and 0.69 ± 0.0 mm vs. 0.55 ± 0.05mm [P < 0.0001]. Also, the mean carotid IMT among hypertensives and controls on the right =0.80 ±0.15mm vs. 0.64 ± 0.06mm [P < 0.0001], and 0.91 ± 0.22mm vs. 0.65 ± 0.06mm [P < 0.0001] on the left. Significant correlation was observed between IMT and age (B = 0.006, P < 0.001 and B = 0.003, P < 0.001), hypertension (B = 0.205, P < 0.001 and B = 0.122, p< 0.001), and duration of hypertension (B = 0.02, P < 0.001 and B = 0.006, P = 0.02) the femoral and carotid arteries respectively.

Conclusion:

The femoral and the carotid artery show similar significantly increased IMT in hypertensive adults. The femoral IMT appears to be a good surrogate marker of atherosclerosis among hypertensive Nigerians.

Association between CYP3A4 gene rs4646437 polymorphism and the risk of hypertension in Chinese population: a case-control study

Using a case–control design, we assessed the association between single nucleotide polymorphisms of CYP3A4 gene rs4646437 polymorphism and the risk of hypertension in Chinese population. We recruited 450 hypertension patients from The First Clinical College, Henan University of Chinese Medicine between June 2017 and May 2018. There was a significant difference in genotype distribution between case group and control group (χ²=18.169, P=0.000). The minor A allele was significantly higher in the case group than that in the control group (31.0 vs 24.8%, P=0.000, odds ratio [OR]=1.36, 95% confidence interval [95% CI]: 1.12–1.66). Significant differences were also observed in other gene models: the GA/AA genotype did not increase the risk of hypertension compared with GG genotype (OR=1.16, 95% CI: 0.90–1.49, P=0.259). Compared with GG/GA genotype, the AA genotype also increased the risk of hypertension (OR=2.34, 95% CI: 1.56–3.50, P=0.000). For additive model, the AA genotype was significantly associated with GG genotype (OR=2.25, 95% CI: 1.49–3.42, P=0.000). The same results were found for AA vs GA (OR=2.50, 95% CI: 1.60–3.89, P=0.000). For the allele genotype, the A allele frequency was significantly higher in the case group than that in the control group (31.0 vs 24.8%, P=0.002). The A allele of CYP3A4 rs4646437 was associated with an increased risk for hypertension (OR=1.36, 95% CI: 1.12–1.66, P=0.002). Our results revealed a possible genetic association between CYP3A4 gene rs4646437 and hypertension, and the AA genotype of rs4646437 increased the risk of hypertension in Chinese Han population, and this effect could be confirmed by multivariable analyses.

Association of traditional cardiovascular risk factors with carotid atherosclerosis among adults at a teaching hospital in south-western Nigeria

Background

Traditional cardiovascular risk factors (CVRFs), which include age, gender, hypertension, diabetes mellitus, dyslipidaemia, smoking, alcohol consumption, chronic kidney disease and obesity, have been shown to be associated with atherosclerosis. We aimed to evaluate the impact of traditional CVRFs on carotid atherosclerosis (CA) in a sample of Nigerian adults.

Methods

We examined 162 subjects with traditional CVRFs in a cross-sectional study. Demographic and clinical data, including history of hypertension, diabetes mellitus, smoking, alcohol intake and chronic kidney disease, as well as systolic and diastolic blood pressure, weight and height were collected. Serum creatinine, fasting blood glucose and lipid profiles were also determined. Carotid intima–media thickness (CIMT) and presence of carotid plaque (CP) were evaluated by high-frequency B-mode ultrasound. Chi-squared and regression analyses were carried out to determine associations between variables of CIMT and CVRF.

Results

Increased CIMT was associated with all CVRFs (p < 0.05) except gender (p > 0.05), while CP was associated with older age, obesity, hypertension and dyslipidaemia (p < 0.05). We found prevalence of increased CIMT was 53.7%, while that of CP was 16.1%. The prevalence of CA (increased CIMT and CP) also increased with increasing number of CVRFs in the subjects. Age ≥ 50 years, hypertension, dyslipidaemia, obesity and alcohol intake explained 78.7% of variance in CIMT, while age ≥ 50 years and hypertension explained 38.0% of variance in CP.

Conclusions

CA was associated with presence and increasing number of traditional CVRFs. A significant percentage of variance in CA was, however, unexplained by traditional CVRFs.

Carotid IMT is more associated with stroke than risk calculators

BACKGROUND

It is unclear whether a natural marker of atherosclerosis (carotid intima-media thickness: CIMT) or calculated risk score is more associated with stroke. We therefore comparatively examined the relationship between CIMT as well as two cardiovascular risk calculators (Omnibus Risk Score -ORS and Framingham Risk Score- FRS) and the occurrence of stroke among hypertensive African patients.

METHODS

CIMT was measured in 555 consecutive consenting hypertensive adults (377 stroke patients and 178 stroke-free subjects). The 10-year cardiovascular risk was calculated for each participant with the FRS and ORS. The strengths of association between FRS, ORS, CIMT, and stroke occurrence were examined using logistic regression. The discriminative capacity of FRS, ORS, and CIMT for stroke occurrence was assessed with c-statistics.

RESULTS

Higher average CIMT (OR 11.71; 95% CI 1.65-83.07; P = 0.01) was strongly associated with stroke after adjusting for age, sex, blood pressure, serum cholesterol, and blood sugar. Neither the FRS (OR: 1.03; CI: 0.89-1.19, P = 0.68) nor the ORS (OR: 1.08; CI: 0.90-1.30; P = 0.41) was significantly associated with stroke. CIMT had a higher c-statistic for differentiating stroke patients from hypertensive controls (right: c = 0.63, P < 0.001; left: c = 0.67, P < 0.001; average: c = 0.66, P < 0.001) than some conventional risk factors. Neither FRS (P = 0.39) nor ORS (P = 0.55) was able to independently differentiate between stroke and hypertensive patients.

CONCLUSION

CIMT, but neither FRS nor ORS, is independently associated with stroke among Nigerian African hypertensive patients. CIMT may be a better tool for estimating the overall risk of stroke than FRS or ORS in this population.

[Contribution of vascular ultrasonography in patients with ischemic strokes in Brazzaville (Congo)]

OBJECTIVE

To determine the prevalence of the carotid lesions during ischemic strokes.

METHODS

This was a descriptive cross-sectional study, conducted in Brazzaville from January 2011 to June 2012 in a consecutive series of 73 patients, victims of a transient ischemic attack or ischemic stroke, documented by a brain computed tomography. All patients underwent vascular ultrasonography of the supra-aortic trunks, carried out within the framework of etiological assessment. The examination searched for plaques, parietal infiltration (measurement of intima-media thickness), and carotid stenosis or occlusion.

RESULTS

There were 49 men (67%) and 24 women (33%), mean age 58.7 ± 11.8 years. Eleven patients (15%) had a transient ischemic attack and 62 (85%) an ischemic stroke. The identified independent vascular risk factors were known and treated hypertension (n=66, 90.4%), dyslipidemia (n=16, 22%), diabetes mellitus (n=9, 12.3%), and smoking (n=5, 6.8%), with on average 2.5 factors per individual. Vascular ultrasonography of the supra-aortic trunks, normal in 44 patients (60.3%) was pathological in the other 29 (39.7%). The main anomalies were atheromatous plaque (n=10, 13.7%), parietal infiltration (n=19, 26%). On average intima-media thickness was 0.86 ± 0.11 mm on the left and 0.83 ± 0.11 mm on the right. Two cases of moderate stenosis were noted on the right and left internal carotids, respectively.

CONCLUSION

This preliminary study confirms the existence of carotid atherosclerosis anomalies during ischemic strokes. These lesions, though non-significant, must nevertheless be taken into consideration when searching for the cause of stroke in high-risk vascular patients.

Stroke risk factors, subtypes, and 30-day case fatality in Abuja, Nigeria

Background:

Stroke is the second leading cause of death and the leading cause of adult disability worldwide. A better understanding of stroke risk factors and outcome may help guide efforts at reducing the community burden of stroke. This study aimed to understand stroke risk factors, imaging subtypes, and 30-day outcomes among adult Nigerians.

Materials and Methods:

We prospectively recruited all patients presenting with acute stroke at the National Hospital Abuja between January 2010 and June 2012. We assessed clinical and laboratory variables, as well as brain computerized tomography, magnetic resonance imaging, and carotid Doppler ultrasound scans. We also assessed case fatality and functional outcome at 30 days after stroke.

Results:

Of 272 patients studied, 168 (61.8%) were males. Age at presentation (mean ± standard deviation) was 56.4 ± 12.7 years in males and 52.9 ± 14.8 years in females (P = 0.039). Neuroimaging was obtained in 96.7% patients, revealing cerebral infarction (61.8%), intracerebral hemorrhage (ICH) (34.8%), and subarachnoid hemorrhage (SAH) (3.4%). Carotid plaques or stenosis ≥50% were detected in 53.2% patients with cerebral infarction. Stroke risk factors included hypertension (82.7%), obesity (32.6%), diabetes (23.5%), hyperlipidemia (18.4%), atrial fibrillation (9.2%), and cigarette smoking (7.7%). At 30 days after stroke, case-fatality rate was 18.8%, whereas modified Rankin Scale (mRS) scores for cerebral infarction, ICH, and SAH were 3.71, 4.21, and 4.56, respectively. Atrial fibrillation, a previous stroke, and age older than 50 years were all associated with worse mRS scores at 30 days.

Conclusion:

Although hypertension, obesity, diabetes mellitus, and atrial fibrillation were important stroke risk factors, in many patients, these were detected only after a stroke. While the commonest stroke subtype was cerebral infarction, observed in almost two-third of patients, SAH was associated with the highest case-fatality rate at 30 days of 44.4%. Larger population-based studies may provide additional data on stroke incidence and outcome among Nigerians.