Distinct factors are related to lower limb atherosclerosis in smokers and nonsmokers

Relationship of blood pressure measured in the calf with arm blood pressure and arterial stiffness: a general population study

AIM

Leg blood pressure (BP) measurement is needed when arm BP evaluation is not feasible, and calf BP, especially when measured in standing position, may have greater association with cardiovascular remodeling than arm BP. This study evaluated the relationship between calf and arm BP, and investigated whether calf BP would be superior to arm BP in predicting increased arterial stiffness [pulse wave velocity (PWV) > 10 m/s].

METHODS

We evaluated clinical and laboratory characteristics, BP measurements, and PWV in 1397 individuals resident in Baependi, Brazil, between 2017 and 2019. Arm BP was measured in the seated and supine positions while calf BP was measured in supine and standing positions using digital oscillometric devices. Carotid-femoral PWV was measured using a noninvasive mechanotransducer.

RESULTS

The sample had 62.7% females, age = 48.1 ± 15.4 years and 8.4% with PWV >10 m/s. Results of linear regression analysis showed that BP values of 140/90 mmHg measured in the arm in supine and seated position were equivalent to calf supine BP values of 164/81 mmHg and 166/78 mmHg and calf standing BP values of 217/137 mmHg and 221/137 mmHg, respectively. Calf-arm BP differences were associated with age, glomerular filtration rate, body mass index, smoking, low-density lipoprotein-cholesterol, diabetes and height. Furthermore, stepwise logistic regression analysis revealed that arm supine systolic BP, but not calf BP measurements, was independently associated with increased arterial stiffness.

CONCLUSION

Thresholds of ≈165/80 mmHg and ≈220/135 mmHg could be used for diagnosing hypertension when only calf measurements in supine and standing positions, respectively, are available. Conversely, calf BP was not superior to arm BP in predicting increased arterial stiffness.

Association of carotid wall layers with atherosclerotic plaques and cardiac hypertrophy in hypertensive subjects

Carotid intima-media thickness (cIMT) is considered a marker of subclinical atherosclerosis and is related to target-organ damage in hypertensive patients. However, increased cIMT may be due to increases in the thickness of intima (cIT) and media (cMT) layers. This study evaluated whether cIMT layers (cIT and cMT) had a greater association with carotid atherosclerotic plaques and left ventricular hypertrophy (LVH) than cIMT in hypertensive subjects. We cross-sectionally evaluated clinical, carotid, and echocardiography characteristics of 186 hypertensive patients followed at an outpatient clinic. High-resolution images of common carotid arteries were obtained by ultrasonography equipped with 10-MHz transducers, and cIT, cMT, and cIMT were manually measured using an image-processing software. Among all participants (n = 186; age = 60.8 ± 10.9 years, 43% males), there were 58% with carotid plaques and 58% with LVH. Mean cIT, cMT, and cIMT values were 0.267 ± 0.060, 0.475 ± 0.107, and 0.742 ± 0.142 mm, respectively. In logistic regression analysis adjusted for relevant covariates, carotid plaques showed stronger association with cIT than with cMT and cIMT. Furthermore, cIT showed greater area under the ROC curve (0.92; 95% CI 0.87-0.96) than cIMT (0.79; 95% CI 0.72-0.85) and cMT (0.64; 95% CI 0.56-0.72) to identify plaques. Conversely, cIT, cMT, and cIMT had modest association and accuracy to identify LVH (area under the ROC curve = 0.61, 0.57, and 0.60, respectively). In conclusion, cIT is a more accurate marker of atherosclerosis than cMT or cIMT, while cIT and cMT provide no incremental value in identifying LVH when compared with cIMT among hypertensive subjects.

Pro B-type Natriuretic Peptide and Midregional Proadrenomedullin are Associated with Incident Carotid Stenosis During Long Term Follow-up

BACKGROUND

Plasma biomarkers may be useful to detect healthy individuals at increased risk for atherosclerotic manifestations, such as carotid artery stenosis. The aim of this longitudinal cohort study was to evaluate new biomarkers in relation to C-reactive protein and conventional risk factors for carotid artery stenosis during long term follow-up METHODS: The following markers were measured in 5550 middle-aged subjects: C-reactive protein, lipoprotein-associated phospholipase A2, proneurotensin, midregional pro-adrenomedullin, midregional pro-atrial natriuretic peptide, N-terminal pro B-type natriuretic peptide, copeptin, and cystatin C. Subjects with prevalent carotid artery stenosis were excluded. Subjects were followed in national patient registers for 23.4 (interquartile range 19.5-24.3) years regarding incident carotid artery stenosis, both operated and non-operated.

RESULTS

When including conventional risk markers in Cox regression, N-terminal pro B-type natriuretic peptide (Hazard ratio 1.36; 95% confidence interval 1.12-1.65; p = 0.002) was independently associated with incident carotid artery stenosis, whereas there were trends for C-reactive protein (HR 1.20; 95% confidence interval 0.98-1.48; p = 0.071), and midregional pro-adrenomedullin (Hazard ratio 1.21; 95% confidence interval 0.99-1.47; p = 0.061). Midregional pro-adrenomedullin (Hazard ratio 1.30; 95% confidence interval 1.03-1.65; p = 0.029) was independently associated with incident surgery for carotid artery stenosis, whereas there was a trend for N-terminal pro B-type natriuretic peptide (Hazard ratio 1.31; 95% confidence interval 1.00-1.72; p = 0.052).

CONCLUSIONS

N-terminal pro B-type natriuretic peptide and midregional pro-adrenomedullin can be used as predictors for clinically detected carotid artery stenosis during long-term follow-up of healthy subjects.