Factors affecting impairment of blood rheology in obese subjects

Clinical Significance of the Cardio-Ankle Vascular Index in Postmenopausal Women With Hypercholesterolemia

Background

The cardio-ankle vascular index (CAVI) is a physiological indicator of arterial elasticity. However, limited information regarding the clinical significance of the CAVI in patients with hypercholesterolemia is available. This cross-sectional study aimed to elucidate the clinical significance of the CAVI for the primary prevention of cardiovascular disease (CVD) among postmenopausal women with hypercholesterolemia.

Methods

A total of 168 untreated postmenopausal hypercholesterolemic women (low-density lipoprotein cholesterol levels ≥ 140 mg/dL, mean age ± standard deviation, 63 ± 10 years) with no history of CVD events were enrolled. The CAVI was measured using commercial devices, after which, its relationships with various clinical parameters, such as carotid artery ultrasonography findings and CVD biomarkers, were examined.

Results

A significant positive correlation was observed between the CAVI and maximum intima-media thickness of the common carotid artery (max-C-IMT), which was evaluated using carotid artery ultrasonography (r = 0.49, P < 0.001). Regarding CVD biomarkers, the CAVI was significantly correlated with estimated glomerular filtration rate (r = -0.18, P < 0.001), high-sensitivity C-reactive protein (r = 0.36, P < 0.001), whole blood passage time as a marker of blood rheology (r = 0.41, P < 0.001), and skin autofluorescence as a marker of advanced glycation end products in tissues (r = 0.46, P < 0.001), although no significant correlation was noted between serum lipid parameters and the CAVI. Multiple regression analysis identified max-C-IMT (β = 0.35, P < 0.001), whole blood passage time (β = 0.18, P = 0.007), skin autofluorescence (β = 0.17, P = 0.011), and age (β = 0.16, P = 0.018) as variables independently associated with CAVI.

Conclusion

The present study indicated that the CAVI is an essential CVD risk factor among postmenopausal women with hypercholesterolemia. Moreover, impaired blood rheology and increase of skin autofluorescence were associated with elevated CAVI in such patients.

Clinical Significance of Low Blood Testosterone Concentration in Men as a Cardiovascular Risk Factor From the Perspective of Blood Rheology

Background

Recent clinical studies have indicated the importance of low blood testosterone concentration or whole blood passage time (WBPT) which reflects blood rheology as a cardiovascular risk factor. On the contrary, there are no reports regarding the association of blood testosterone concentrations and WBPT. This cross-sectional study aimed to elucidate the clinical significance of low blood testosterone concentration in men as a cardiovascular risk factor from the perspective of blood rheology using WBPT.

Methods

In total, 382 male patients with traditional cardiovascular risk factor and no history of cardiovascular disease (age (mean ± standard deviation (SD)), 64 ± 10 years) were enrolled. Serum total testosterone concentration (T-T) was measured as a marker of testosterone level in vivo, and WBPT was also measured using microchannel array flow analyzer as a commercial device. The relationship between T-T and WBPT was evaluated.

Results

There was a significantly negative correlation between T-T and WBPT (r = -0.45; P < 0.001). Furthermore, multiple regression analysis revealed that T-T (β = -0.25; P < 0.001) could be selected as an independent variable when WBPT was used as a subordinate factor. According to receiver operating characteristic curve analysis and the result of the previous report that determined WBPT of > 72.4 s as a risk for incidence of primary cardiovascular disease, T-T of < 551.4 ng/dL is the optimal cut-off point for discriminating high WBPT.

Conclusions

The study results showed that T-T is independently and inversely associated with WBPT in male patients with traditional cardiovascular risk factor and no history of cardiovascular disease. In addition, this study suggests that the incidence of primary cardiovascular events can be prevented by maintaining T-T at approximately ≥ 550 ng/dL from the perspective of blood rheology.

The relationship between the rheological behavior of RBCs and angiogenesis in the morbidly obese

OBJECTIVE

The aim of this study was to investigate the relationship between red blood cell (RBC) aggregation and deformability and angiogenesis parameters in obese patients.

METHODS

We studied 35 obese subjects and 20 non-obese people as a control group. Angiogenesis was detected using Bio-Plex Pro Human Angiogenesis Multiplex Assays. The RBC aggregation and deformability of the red blood cell aggregation were performed by the Laser-assisted Optical Rotational Cell Analyser - LORCA.

RESULTS

The aggregation index and the syllectogram's amplitude were significantly higher in the obese patients, whereas the aggregation half-time (t1/2) was lower compared with the control group. The deformability of RBC expressed as EI was significantly lower in the obese group than it was in the control group. All angiogenesis parameters were higher in obese individuals than they were in the control group. Significant differences were observed in angiopoietin 2 (p = 0.048), folistin (p = 0.0017), G-CSF (p = 0.042), HGF (p = 0.016), and PECAM-1 (p = 0.014). The VEGF tended to be higher in the obese patients than in the control group (p = 0.09); nevertheless, the concentration of PDGF-BB was similar in both groups. EI at shear stresses of 18.49 Pa and 30.2 Pa was strongly correlated with all angiogenesis parameters. No correlations were found between the studied RBC aggregation indices and angiogenesis parameters. Multivariate analyses indicated that only HGF was an independent predictor of RBC deformability at 18.49 Pa (β-0.83, P < 0.000005) and at 30.2 Pa (β-0.83, P < 0.00005).

CONCLUSIONS

The study found that there are relationships between enhanced RBC rigidity and angiogenesis status in obese subjects. Because this correlation between angiogenesis and RBC deformability is presented for the first time, the physiological importance of the relationship requires further research.

Clinical Impact of Hemorheology on Subclinical Myocardial Injury in Patients with Hypertension

Background

The blood concentration of high-sensitivity cardiac troponin T (hs-cTnT) is a useful biomarker for myocardial injury or the pathogenesis of hypertension. Little is known about the relationship between hemorheology and myocardial injury in patients with hypertension. This cross-sectional study aimed to clarify the clinical impact of hemorheology on subclinical myocardial injury assessed with a microchannel array flow analyzer (MC-FAN) and its impact on hs-cTnT in patients with hypertension.

Methods

A total of 447 outpatients (men: 181; women: 266; mean age: 65 ± 13 years), with no history of cardiovascular disease, including admission for heart failure, who were undergoing treatment for hypertension, were enrolled. Whole blood passage time (WBPT) as a marker of hemorheology was measured with a MC-FAN, and the relationship between hs-cTnT levels and various clinical parameters, including WBPT, was examined.

Results

hs-cTnT levels were detected in 400 patients (89.5%). WBPT was significantly higher in patients with detectable hs-cTnT levels than in those with undetectable hs-cTnT levels (60.5 ± 16.8 s versus 50.2 ± 14.2 s, P < 0.001). In patients with detectable hs-cTnT levels, there was a significant positive correlation between WBPT and hs-cTnT level (r = 0.33; P < 0.001). Multiple regression analysis revealed that WBPT was an independent variable when hs-cTnT was a subordinate factor (β = 0.15; P < 0.01). Receiver-operating characteristic curve analysis indicated that a cutoff value for WBPT of 55.6 s yielded the largest area under the curve (0.744; P < 0.001) for discriminating high hs-cTnT levels as ≥ 0.014 ng/mL.

Conclusion

The results indicate that WBPT is independently associated with hs-cTnT in hypertensive patients with no history of cardiovascular events, suggesting that impairment of hemorheology in small cardiac vessels causes subclinical myocardial injury. In addition, the study suggests that progression of myocardial injury can be prevented by maintaining WBPT at approximately ≤ 55 s.

Usefulness of the Whole Blood Passage Time as a Predictor of Primary Cardiovascular Events in Patients With Traditional Cardiovascular Risk Factors

BACKGROUND

Recent clinical studies have reported that impaired hemorheology is a significant cardiovascular risk factor, but there has been no prospective study of its relationship with cardiovascular events. The aim of this prospective study was to assess the efficacy of whole blood passage time (WBPT), measured by a microchannel array flow analyzer (MC-FAN), as a predictor of primary cardiovascular events in patients with traditional cardiovascular risk factors.

METHODS

The study enrolled 1,134 outpatients with traditional cardiovascular risk factors but no history of cardiovascular events (438 men and 696 women; mean ± standard deviation age, 67 ± 11 years). Based on the value of WBPT, the patients were assigned to one of three groups: L (low, WBPT < 50 s; n = 499), M (medium, WBPT 50 - 70 s; n = 295), or H (high, WBPT > 70 s; n = 340). The utility of the WBPT as a predictor of primary cardiovascular events was evaluated.

RESULTS

During the follow-up period (median 81.9 months), major adverse cardiovascular events (MACE) occurred in 95 cases (L, 21 cases (4.2%); M, 24 cases (8.1%); H, 50 cases (14.7%); P < 0.001, log-rank test). In multivariate Cox regression analyses, the risk for MACE was significantly higher in group H than in group L (hazard ratio, 2.32; 95% confidence interval, 1.31 - 3.20; P < 0.01). A WBPT cut-off of 72.4 s yielded the largest area under the curve of 0.705 (95% confidence interval: 0.678 - 0.732), with a sensitivity of 51.7% and specificity of 85.4% for discriminating between those who did and did not experience MACE during the follow-up period.

CONCLUSION

This study showed that WBPT evaluated by a MC-FAN was a predictor of primary cardiovascular events in patients with traditional cardiovascular risk factors.

Effect of diet on blood viscosity in healthy humans: a systematic review

Background

Increased whole blood viscosity is associated with increased risk of morbidity and mortality of several life-threatening diseases, including cardiovascular and cerebrovascular disease. The effect of diet on human health has been indicated in many studies, and a health dietary pattern can reduce the incidence of several chronic diseases.

Objective

The aim of this systematic review was to assess the effect of diet on blood viscosity and related parameters such as haematocrit (HCT).

Methods

This systematic review was carried out in 2017. MEDLINE, Embase, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials were searched from inception to 2 May 2017. We selected and included randomized clinical trials (RCTs) in the study. The inclusion criteria were articles that describe the effect of any types of local and traditional diet on blood viscosity in apparently healthy individuals.

Results

Three randomized controlled trials were included in this systematic review. Different diets were used in the included trials. In one study, ingested dried–bonito broth (DBB) for four weeks, significantly reduced the blood passage time in the intervention group from 55.4±3.4 to 47.6±2.0 sec (mean ± SEM, p<0.05) compared with no significant change in the placebo group. Another study has shown significantly increased blood fluidity score in a vegetarian group in contrast to the control group after six weeks. In the last study, plasma viscosity was significantly decreased in a group which used onion–olive-oil capsules compared to the placebo group, with a highly significant difference between the two groups (p=0.0015).

Conclusions

Our components of food diets may decrease blood viscosity in health status. Better and expanded methodology may improve our results.

Association of Hemorheology With High-Sensitivity Cardiac Troponin T Levels in Patients With Type 2 Diabetes Mellitus Assessed by Microchannel Array Flow Analyzer

Background

Recent studies on high-sensitivity cardiac troponin T (hs-cTnT) and whole blood passage time (WBPT), estimated by hemorheology assessed with the microchannel array flow analyzer (MC-FAN), have revealed the significance of cardiovascular risk factors. However, there are no known reports on the relationship between these two clinical parameters. This cross-sectional study aimed to clarify the associations between WBPT and hs-cTnT levels in patients with type 2 diabetes mellitus from the perspective of subclinical myocardial injury or the primary prevention of cardiovascular events.

Methods

A total of 301 outpatients (men, 116; women, 185; mean age, 65 ± 11 years), with no history of cardiovascular diseases, undergoing treatment for diabetes mellitus were enrolled. Hs-cTnT levels and WBPT were measured using a commercial device, and the relationship between hs-cTnT levels and various clinical parameters, including WBPT, was examined.

Results

Hs-cTnT levels were detected in 261 (86.7%) patients. WBPT was significantly higher in patients with detectable hs-cTnT levels than in those with undetectable hs-cTnT levels (64 ± 18 s vs. 51 ± 13 s, P < 0.001). In patients with detectable hs-cTnT levels, there was a significantly positive correlation between WBPT and hs-cTnT levels (r = 0.40; P < 0.001). Furthermore, multiple regression analysis revealed that WBPT (β = 0.24; P < 0.001) was an independent variable when hs-cTnT was a subordinate factor. Conversely, patients with high (≥ 70 s; odds ratio, 5.3 (95% CI, 1.6 - 16.1); P < 0.01) and median (50.2 - 69.8 s; odds ratio, 3.8 (95% CI, 1.2 - 12.4); P < 0.05) WBPT had a significantly higher risk for high hs-cTnT levels (≥ 0.014 ng/mL) than those with low WBPT (≤ 50.0 s).

Conclusions

The results of this study indicated independent associations of hemorheology with hs-cTnT in patients with type 2 diabetes mellitus assessed by MC-FAN. We suggest that an increase in hs-cTnT levels can be prevented by maintaining WBPT at ≤ 50.0 s.

Relationship Between Hemorheology Assessed Using Microchannel Array Flow Analyzer and Kidney Function in Hypertensive Patients

Background

Kidney function is known to be closely associated with the pathogenesis of hypertension. In contrast, hemorheology assessed using microchannel array flow analyzer (MC-FAN) has demonstrated the significance of cardiovascular risk factors in recent clinical studies. The present cross-sectional study aimed to clarify the relationship between hemorheology assessed by MC-FAN and kidney function in hypertensive patients from the perspective of primary prevention of cardiovascular events.

Methods

In total, 453 outpatients undergoing treatment for hypertension (176 men and 277 women; mean age ± standard deviation: 65 ± 13 years) with no history of cardiovascular disease were enrolled. Whole blood passage time (WBPT) was measured using MC-FAN as a marker of hemorheology, and the relationships with various clinical parameters including kidney function were examined.

Results

A significant correlation was observed between WBPT and the parameters of kidney function such as estimated glomerular filtration rate (r = -0.14, P < 0.01), urinary albumin excretion (r = 0.40, P < 0.001), and renal resistive index (r = 0.44, P < 0.001). Furthermore, multivariate analysis demonstrated urinary albumin excretion, renal resistive index, skin autofluorescence, derivatives of reactive oxygen metabolites, and hematocrit as independent variables for WBPT as a subordinate factor.

Conclusions

The results of the present study indicate that hemorheology assessed by the MC-FAN is significantly associated with markers of kidney function, such as albuminuria and increased renovascular resistance, in hypertensive patients.

Impact of Hemorheology Assessed by the Microchannel Method on Pulsatility Index of the Common Carotid Artery in Patients With Type 2 Diabetes Mellitus

Background

Type 2 diabetes mellitus is known to be closely associated with the risk of ischemic stroke. Recent clinical studies have reported that a high pulsatility index (PI) of the cerebral or carotid artery, which is estimated by ultrasonography, also reflects a risk of ischemic stroke. This cross-sectional study aimed to clarify the impact of hemorheology assessed by the microchannel method on the PI of the common carotid artery (CCA) in patients with type 2 diabetes mellitus in terms of the primary prevention of ischemic stroke.

Methods

In total, 349 outpatients on treatment for type 2 diabetes mellitus (131 men and 218 women; mean age ± standard deviation: 65 ± 11 years) with no history of cardiovascular events, including ischemic stroke, were enrolled. The whole blood passage time (WBPT) as a marker of hemorheology and the PI of CCA were measured using commercial devices, and their relationships to various clinical parameters were examined.

Results

A significant positive correlation was observed between WBPT and the PI of CCA (r = 0.49, P < 0.001). Furthermore, multivariate analysis revealed that patients with high WBPT (≥70 s) had significantly higher risk (odds ratio: 5.2; 95% confidence interval: 2.4 - 9.2; P < 0.001) of being detected with a high PI of CCA (≥ 2) than those with low WBPT (≤ 52.0 s).

Conclusion

The results of this study indicated that WBPT was an important determination factor for the PI of CCA, suggesting that an increase in WBPT can potentially predict the incidence of ischemic stroke in patients with type 2 diabetes mellitus.

Relationship between cardiovascular risk factors and hemorheology assessed by microchannel method in patients with type 2 diabetes mellitus

Aim

In addition to atherosclerosis, impairment of blood rheology is an important factor in cardiovascular events. The present study attempted to clarify the relationship between hemorheology and cardiovascular risk factors in patients with type 2 diabetes mellitus assessed by a microchannel method.

Methods

We enrolled 294 patients with type 2 diabetes mellitus (109 males and 185 females; mean age, 69 ± 11 years) with no history of cardiovascular events. Hemorheology was evaluated with a microchannel array flow analyzer, and the relationship between whole-blood passage time (WBPT) and various clinical parameters was examined.

Results

WBPT was significantly correlated with advanced glycation end-product (AGE) levels at the skin (r = 0.49, p < 0.001), serum reactive oxygen metabolite concentrations (oxidative stress markers) (r = 0.25, p < 0.001), the cardio-ankle vascular index (CAVI, arterial function marker) (r = 0.32, p < 0.001), and a number of classical cardiovascular risk factors in an individual (r = 0.45, p < 0.001). Multiple regression analysis revealed that these factors were selected as independent variables for WBPT as a subordinate factor.

Conclusion

Hemorheology is significantly associated with novel cardiovascular risk factors, such as AGEs, in vivo oxidative stress, and CAVI, and clustering of classical cardiovascular risk factors in patients with type 2 diabetes mellitus.

The effects of obesity on CD47 expression in erythrocytes

BACKGROUND

To investigate the effects of obesity on CD47, phosphatidylserine (PS) exposure, and Caspase-8 and Caspase-3 activities in erythrocytes.

METHODS

The study included 25 morbidly obese patients and 20 healthy people as the control group. We evaluated CD47 expression on the red blood cell (RBC) membrane surface and eryptosis markers such as PS externalization and caspase activity using flow cytometric analyses.

RESULTS

CD47 expression on the RBC surface was significantly lower in obese patients than in the control group (P = 0.000001). We did not find significant differences in the Caspase-3 and Caspase-8 activities between the obese and nonobese control groups. Additionally, we did not find differences in PS exposure on erythrocyte membranes. The fibrinogen levels were higher in the obese group than they were in the control group (P = 0.00002). Correlations between CD47 expression and body mass index (r = -0.65; P = 0.0004), waist circumference (r = -0.54; P = 0.0052), and fibrinogen (r = 0.57; P = 0.0024) were found. Univariate analyses revealed that body mass index, waist circumference, hip circumference, and fibrinogen levels were potential predictors of CD47 expression. Multivariate analyses found that fibrinogen levels (β = 0.4708; P = 0.045) independently predicted CD47 expression.

CONCLUSIONS

The study demonstrated that CD47 expression is decreased on the surface of RBCs in obese subjects. These changes in CD47 expression on the RBC surface may be an adaptive response to hyperfibrinogenemia associated with obesity. © 2015 International Clinical Cytometry Society.

Blood viscosity as a sensitive indicator for paclitaxel induced oxidative stress in human whole blood

In this study, the in vitro effects of paclitaxel (PTX) and Cremophor-EL (CrEL) on blood viscosity and oxidative stress markers were investigated. Whole-blood samples were collected from healthy volunteers and co-incubated with PTX, CrEL or their combination then compared with control blood samples. After a 24 h incubation time, the whole-blood viscosity (WBV), erythrocyte sedimentation rate (ESR), levels of whole-blood malondialdehyde (MDA), protein carbonyl content (PCC) and reduced glutathione (GSH) were determined. Moreover, plasma nitrite and plasma sialic acid (SA) values were measured. The present results revealed that the incubation of blood samples with PTX, CrEL or PTX plus CrEL significantly increased the values of WBV, ESR, MDA and PCC compared to control samples. In contrast, a significant decrease in levels of GSH, SA and nitrite was observed after incubation of blood samples with tested agents compared to control. The effects of tested agents on the measured parameters were more pronounced in the case of blood samples treated with PTX plus CrEL. The present study demonstrates that PTX-induced oxidative stress is associated with an increase of WBV.

Long-term prognosis and clinical characteristics of young adults (≤40 years old) who underwent percutaneous coronary intervention

BACKGROUND

Limited data exist regarding the long-term prognosis of percutaneous coronary intervention (PCI) in young adults. The aim of this study was to retrospectively assess the long-term clinical outcomes in young patients who underwent PCI.

METHODS AND RESULTS

Between 1985 and 2011, 7649 consecutive patients underwent PCI, and data from 69 young adults (age ≤40 years) and 4255 old adults (age ≧65 years) were analyzed. A Cox proportional hazards regression analysis was used to determine the independent predictors of a composite endpoint that included all-cause death and acute coronary syndrome (ACS) during the follow-up period. The mean age of the 69 young patients was 36.1±4.9 years, and 96% of them were men. Approximately 30% were current smokers, and their body mass index (BMI) was 26.7±5.0kg/m(2). The prevalence of diabetes and hypertension was 33% and 48%, respectively. All patients had ≥1 conventional cardiovascular risk factor. At a median follow-up of 9.8 years, the overall death rate was 5.8%, and new-onset ACS occurred in 8.7%. Current smoking was an independent predictor of the composite endpoint (hazard ratio 4.46, confidence interval 1.08-19.1, p=0.04) for young adults.

CONCLUSION

Current smoking and obesity (high BMI) are the important clinical characteristics in young Japanese coronary heart disease patients who undergo PCI. The long-term prognosis in young patients is acceptable, but current smoking is a significant independent predictor of death and the recurrence of ACS in young Japanese coronary heart disease patients who are obese.