High-sensitivity C-reactive protein and ankle brachial index in a finnish cardiovascular risk population

Inflammatory markers and extent and progression of early atherosclerosis: Meta-analysis of individual-participant-data from 20 prospective studies of the PROG-IMT collaboration

BACKGROUND

Large-scale epidemiological evidence on the role of inflammation in early atherosclerosis, assessed by carotid ultrasound, is lacking. We aimed to quantify cross-sectional and longitudinal associations of inflammatory markers with common-carotid-artery intima-media thickness (CCA-IMT) in the general population.

METHODS

Information on high-sensitivity C-reactive protein, fibrinogen, leucocyte count and CCA-IMT was available in 20 prospective cohort studies of the PROG-IMT collaboration involving 49,097 participants free of pre-existing cardiovascular disease. Estimates of associations were calculated within each study and then combined using random-effects meta-analyses.

RESULTS

Mean baseline CCA-IMT amounted to 0.74 mm (SD = 0.18) and mean CCA-IMT progression over a mean of 3.9 years to 0.011 mm/year (SD = 0.039). Cross-sectional analyses showed positive linear associations between inflammatory markers and baseline CCA-IMT. After adjustment for traditional cardiovascular risk factors, mean differences in baseline CCA-IMT per one-SD higher inflammatory marker were: 0.0082 mm for high-sensitivity C-reactive protein (p < 0.001); 0.0072 mm for fibrinogen (p < 0.001); and 0.0025 mm for leucocyte count (p = 0.033). 'Inflammatory load', defined as the number of elevated inflammatory markers (i.e. in upper two quintiles), showed a positive linear association with baseline CCA-IMT (p < 0.001). Longitudinal associations of baseline inflammatory markers and changes therein with CCA-IMT progression were null or at most weak. Participants with the highest 'inflammatory load' had a greater CCA-IMT progression (p = 0.015).

CONCLUSION

Inflammation was independently associated with CCA-IMT cross-sectionally. The lack of clear associations with CCA-IMT progression may be explained by imprecision in its assessment within a limited time period. Our findings for 'inflammatory load' suggest important combined effects of the three inflammatory markers on early atherosclerosis.

Association of Inflammatory Cytokines with Traditional and Nontraditional Cardiovascular Risk Factors in Indians with known Coronary Artery Disease

BACKGROUND

Inflammatory processes are implicated in the etiology of cardiovascular disease (CVD). Data on the association of inflammatory markers with cardiovascular risk factors in Indian patients with CVD are limited.

AIM

This study was conducted with the aim to evaluate the association of inflammatory markers with traditional and nontraditional cardiovascular risk factors in angiographically proven coronary artery disease (CAD) patients.

SUBJECTS AND METHODS

We studied the association of serum highly sensitive C-reactive protein (hsCRP) (0.1-37.9 mg/l), interleukin-6 (IL-6) (2-253.2 pg/ml) and tumor necrosis factor-alpha (TNF-α) (8-525.8 pg/ml) with cardiovascular risk factors in 300 (M: 216, F: 84; mean age: 60.9 (12.4) years) CAD patients. All patients were evaluated for anthropometry and cardiovascular risk factors, and blood samples were collected for biochemical and inflammatory markers. Statistical analysis was carried out using SPSS Version 20.

RESULTS

Mean hsCRP, IL-6 and TNF-α in study population were 11.7 (9.7) mg/l, 64.5 (75.2) pg/ml, and 25.3 (40.9) pg/ml respectively. A total of 73.6% (221/300) patients had hsCRP levels >3.0 mg/l. All inflammatory markers were significantly higher and showed a positive correlation with dyslipidemia, diabetes mellitus, and/or hypertension (HTN). TNF-α had a negative correlation with age and positive correlation with smoking. Only IL-6 and hsCRP had a positive correlation with insulin resistance and negative correlation with insulin secretion. Among lipid parameters, triglyceride had a positive correlation, and high density lipoprotein had a negative correlation with all inflammatory markers. There was a progressive increase in the percentage of subjects with diabetes, HTN, and dyslipidemia with increasing levels of inflammatory markers.

CONCLUSIONS

Indian patients with CAD had significantly high levels of inflammatory markers, which were related to cardiovascular risk factors.

Surface-enhanced Raman spectral biomarkers correlate with Ankle Brachial Index and characterize leg muscle biochemical composition of patients with peripheral arterial disease

Peripheral arterial disease (PAD) is characterized by atherosclerotic blockages of the arteries supplying the lower extremities, which cause a progressive accumulation of ischemic injury to the skeletal muscles of the lower limbs. This injury includes altered metabolic processes, damaged organelles, and compromised bioenergetics in the affected muscles. The objective of this study was to explore the association of Raman spectral signatures of muscle biochemistry with the severity of atherosclerosis in the legs as determined by the Ankle Brachial Index (ABI) and clinical presentation. We collected muscle biopsies from the gastrocnemius (calf muscle) of five patients with clinically diagnosed claudication, five patients with clinically diagnosed critical limb ischemia (CLI), and five control patients who did not have PAD. A partial least squares regression (PLSR) model was able to predict patient ABI with a correlation coefficient of 0.99 during training and a correlation coefficient of 0.85 using a full cross‐validation. When using the first three PLS factor scores in combination with linear discriminant analysis, the discriminant model was able to correctly classify the control, claudicating, and CLI patients with 100% accuracy, using a full cross‐validation procedure. Raman spectroscopy is capable of detecting and measuring unique biochemical signatures of skeletal muscle. These signatures can discriminate control muscles from PAD muscles and correlate with the ABI and clinical presentation of the PAD patient. Raman spectroscopy provides novel spectral biomarkers that may complement existing methods for diagnosis and monitoring treatment of PAD patients.

Raman spectroscopy is capable of detecting and measuring unique biochemical signatures of skeletal muscle. These signatures can discriminate control muscles from peripheral arterial disease (PAD) muscles and correlate with the ABI and clinical presentation of the PAD patient. Raman spectroscopy provides novel spectral biomarkers that may complement existing methods for diagnosis and monitoring treatment of PAD patients.