Pulse Pressure Is an Independent Predictor for the Progression of Aortic Wall Calcification in Patients With Controlled Hyperlipidemia

Pathophysiology of carotid atherosclerosis: Calcification, intraplaque haemorrhage and pulse pressure as key players

PURPOSE

Intraplaque haemorrhage (IPH) is a well-known risk factor for faster plaque progression (volume increase); however, its etiology is unclear. We aimed at determining what other local plaque- and systemic factors contribute to plaque progression and to the development and progression of IPH.

METHODS

We examined 98 asymptomatic participants with carotid plaque using serial multi-contrast magnetic resonance imaging. We measured the percent of wall volume (%WV=100 x [wall volume] / [total vessel volume]) and measured IPH and calcification volumes. We used generalized estimating equations-based regression to analyze predictors of %WV change and new IPH while accounting for covariates (sex, age and statin use), and multiple non-independent observations per participant.

RESULTS

Total follow-up was 1.8 ± 0.8 years on average. The presence of IPH (β: 0.6 %/y, p = 0.033) and calcification (β: 1.2 %/y, p = 0.028) were each associated with faster plaque progression. New IPH, detected on a subsequent scan in 4 % of arteries that did not initially have IPH, was associated with larger calcification (odds ratio [OR]: 2.6 per 1-SD increase, p = 0.038) and higher pulse pressure (OR: 2.3 per 1-SD increase, p = 0.016). Larger calcification was associated with greater increases in pulse pressure (β: 1.4 mm Hg/y per 1-SD increase, p = 0.040).

CONCLUSIONS

IPH and calcification are each independently associated with faster plaque progression. The association of carotid calcification to increased pulse pressure and new IPH development suggests a possible mechanism by which calcification drives IPH development and plaque progression.

Effect of Doxycycline on Progression of Arterial Calcification in the Noninvasive Treatment of Abdominal Aortic Aneurysm Clinical Trial (N-TA(3)CT)

BACKGROUND

Doxycycline has been shown to prevent arterial calcification via attenuation of matrix metalloproteinases (MMP) in preclinical models. We assessed the effects of doxycycline on progression of arterial calcification in patients enrolled in the Non-Invasive Treatment of Abdominal Aortic Aneurysm Clinical Trial (N-TA3CT).

METHODS

Two hundred and sixty-one patients were randomized to 100 mg doxycycline twice daily or placebo. Arterial calcification was measured in abdominal vessels on noncontrast computed tomography scans. Patients with baseline computed tomography scan and 1 or more follow-up scans within the 2-year study were included for analysis. For individual arteries, mean change in iliofemoral artery calcification over time was calculated via linear regression. Serum MMP-3 and MMP-9 levels were measured at baseline and 6 months.

RESULTS

Sixty-five patients in the doxycycline and 66 in the placebo arm were included in this analysis. Baseline characteristics between the groups were similar. The unadjusted mean change in iliofemoral calcium score per year trended toward higher values in patients treated with doxycycline compared with placebo (322 ± 399 units/year vs. 217 ± 307 units/year, P = 0.09). After 6 months, changes in serum MMP-3 and MMP-9 levels were not significantly different between study arms.

CONCLUSIONS

In patients with small aortic aneurysm, treatment with doxycycline 100 mg twice daily did not decrease circulating levels of the matrix degrading enzymes MMP-3 and 9 or alter the progression of arterial calcification.

Relationship between pulse pressure and body mass index in active-duty Royal Thai Army personnel in Thailand

BACKGROUND

Elevated pulse pressure (PP) is a robust independent predictor of cardiovascular diseases. The relationship between PP and body mass index (BMI) was presented in a few studies. However, the findings were inconsistent. Therefore, the aim of the present study is to identify the association between elevated PP and BMI using a large sample of active-duty Royal Thai Army (RTA) personnel.

METHODS

A cross-sectional study was conducted through the use of the dataset obtained from the annual health examination database of RTA personnel in Thailand in 2022. BMI 25.0-29.9 kg/m² was classified as obesity I, whereas BMI ≥ 30.0 kg/m² was classified as obesity II. Elevated PP was defined as PP ≥ 50 mmHg. Multivariable linear regression and log-binomial regression models were utilized for determining the association between elevated PP and BMI.

RESULTS

A total of 62,113 active-duty RTA personnel were included in the study. The average BMI was 25.4 ± 3.8 kg/m², while the average PP was 50.1 ± 11.2 mmHg. Compared to individuals with normal weight, the [Formula: see text] coefficients of PP and BMI were 1.38 (95% CI: 1.15-1.60) and 2.57 (95% CI: 2.25-2.88) in individuals with obesity I and obesity II, respectively. Effect modification by high blood pressure (BP) on the association between elevated PP and BMI was observed. Among participants with normal BP, in comparison with BMI of 18.5-22.9 kg/m², the adjusted prevalence ratio (PR) for elevated PP was 1.23 (95% CI: 1.19-1.28) and 1.41 (95% CI: 1.35-1.48) in those with obesity I and obesity II, respectively. Meanwhile, among individuals with high BP, the adjusted PR for elevated PP was 1.05 (95% CI: 1.01-1.08) and 1.09 (95% CI: 1.06-1.13) in those with obesity I and obesity II, respectively.

CONCLUSION

PP was positively associated with BMI in active-duty RTA personnel. High BP was the modifier of the association between PP and BMI. A weaker association between elevated PP and BMI was observed among RTA personnel with high BP.

Predictors and impact of low diastolic blood pressure and widened pulse pressure following transcatheter aortic valve replacement

BACKGROUND

The association between post-operative diastolic blood pressure (DBP) and pulse pressure (PP) with outcomes following transcatheter aortic valve replacement (TAVR) remains unclear. We sought to assess the prevalence, predictors, and impact of post-operative DBP and PP on presence of post-procedural aortic insufficiency (AI) and mortality in adults undergoing TAVR.

METHODS

The study population included 194 patients who underwent TAVR from 2016 to 2017 at an academic tertiary medical center, of which 176 had invasive arterial pressures available postoperatively. Low DBP and widened PP were defined as ≤40 mmHg and ≥80 mmHg respectively on invasive arterial line on post-operative day 1. Clinical outcomes of interest included post-procedural AI and 1-year all-cause mortality.

RESULTS

Post-operative low DBP and widened PP were noted in 32.4% and 58.5% of the study population. No significant association between post-operative AI and low DBP (p = 0.82) or widened PP (p = 0.32) was noted. There was a trend toward higher rates of mortality in patients with low DBP (19.3% vs 9.2%, p = 0.06) but no difference in mortality in patients with widened PP (10.7% vs 15.1%, p = 0.39) or those with ≥1+ post-procedural AI (16.7% vs 10.7%, p = 0.32). In multivariable analysis, low DBP was associated with a trend toward higher rates of 1-year mortality [odds ratio (OR) 2.43, 95% confidence interval (CI) 0.97-6.11, p = 0.06]. When excluding patients with a post-operative invasive systolic blood pressure < 80 mmHg, low DBP was associated with significantly higher risk-adjusted mortality at 1 year [OR 2.75, 95% CI (1.07-7.07), p = 0.04].

CONCLUSIONS

In this contemporary study of adults undergoing TAVR, low DBP and widened PP were widely prevalent post TAVR. Low DBP was associated with a trend toward higher rates of 1-year mortality but not with post-procedural AI.

Calcification prevalence in different vascular zones and its association with demographics, risk factors, and morphometry

Vascular calcification is associated with a higher incidence of cardiovascular events, but its prevalence in different vascular zones and the influence of demographics, risk factors, and morphometry remain insufficiently understood. Computerized tomography angiography scans from 211 subjects 5-93 yr old (mean age 47 ± 24 yr, 127 M/84 F) were used to build 3D vascular reconstructions and measure arterial diameters, tortuosity, and calcification volumes in six vascular zones spanning from the ascending thoracic aorta to the pelvic arteries. A machine learning random forest algorithm was used to determine the associations between calcification in each zone with demographics, risk factors, and vascular morphometry. Calcification appeared during the fourth decade of life and was present in all subjects after 65 yr. The abdominal aorta and the iliofemoral segment were the first to develop calcification, whereas the ascending thoracic aorta was the last. Demographics and risk factors explained 33-59% of the variation in calcification. Age, creatinine level, body mass index, coronary artery disease, and hypertension were the strongest contributors, whereas the effects of sex, race, tobacco use, diabetes, dyslipidemia, and alcohol and substance use disorders on calcification were small. Vascular morphometry did not directly and independently affect calcium burden. Vascular zones develop calcification asynchronously, with distal segments calcifying first. Understanding the influence of demographics and risk factors on calcium prevalence can help better understand the disease pathophysiology and may help with the early identification of patients that are at higher risk of cardiovascular events.NEW & NOTEWORTHY We investigated the prevalence of vascular calcification in different zones of the aorta and pelvic arteries using computerized tomography angiography reconstructions and have applied machine learning to determine how calcification is affected by demographics, risk factors, and morphometry. The presented data can help identify patients at higher risk of developing vascular calcification that may lead to cardiovascular events.

Abdominal aorta calcification predicts cardiovascular but not non-cardiovascular outcome in patients receiving peritoneal dialysis: A prospective cohort study

Abdominal aorta calcification (AAC) is associated with worse clinical outcomes in dialysis patients. However, the long-term prognostic values of AAC to cardiovascular (CV) and non-CV mortality in patients starting peritoneal dialysis (PD) remain unknown. This study is aimed to the analyze the predictive power of AAC to CV and non-CV mortality in PD patients. We prospectively enrolled 123 patients undergoing PD. All patients received quantitative analysis of AAC via abdominal computer tomography at enrollment. The AAC ratio was measured by the area of the whole aorta affected by aortic calcification above the iliac bifurcation. The CV mortality and non-CV mortality during the follow-up period were investigated using the Cox proportional hazard model and time-dependent receiver operating characteristic (ROC) analysis. After median 6.8 (interquartile range, 3.6-9.2) years of follow-up, there were 18 CV mortality, 24 non-CV mortality and 42 total mortality. The age and AAC ratio were significantly higher in CV mortality group compared with others without CV mortality. In time-dependent ROC analysis, AAC had excellent predictive power of CV mortality (AUC:0.787) but not non-CV mortality (AUC:0.537). The best cutoff value of AAC ratio to predict CV mortality was 39%. In addition, AAC was not associated with non-CV mortality but remained to be a significantly predictor of CV mortality after adjusted with clinical covariates in different Cox proportional hazard models. AAC has excellent prognostic value of CV mortality but is unable to predict non-CV morality in patients undergoing PD.

Whole milk consumption is associated with lower risk of coronary artery calcification progression: evidences from the Multi-Ethnic Study of Atherosclerosis

PURPOSE

Coronary artery calcification (CAC) progression is a strong predictor of cardiovascular disease (CVD) morbidity and mortality. However, the association between whole milk and CAC progression remains unknown. Recent studies highlighted beneficial effects of short chain fatty acids (SCFA) from whole milk on CVD. In this study, we attempted to investigate the relationship between whole milk consumption and CAC progression, and the potential effect of SCFA in it.

METHODS

We analyzed a population-based cohort with 5273 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) who completed a dietary questionnaire at baseline. CAC was measured at baseline and subsequent follow-up examinations by multi-detector computed tomography (MDCT) scans with Agatston scores. CAC progression was defined as increased CAC scores in the follow-up from the baseline exam.

RESULTS

Participants consuming whole milk exhibited lower baseline CAC and CAC progression than those who never/rarely consumed whole milk (P < 0.001 and P = 0.010, respectively). Moreover, multivariable logistic regression analysis demonstrated that whole milk intake was independently associated with lower CAC progression (OR 0.765; 95% CI 0.600-0.977; P = 0.032), especially in males, participants with age ≤ 64 years and with body mass index (BMI) ≤ 25 kg/m². Mediation analysis further showed that caproic acid, one kind of SCFA, partly mediated protective effects of whole milk on CAC progression.

CONCLUSIONS

Self-reported whole milk consumption was inversely associated with CAC progression in community-dwelling participants, especially in those at relatively low cardiovascular risks. The beneficial effect was partially mediated by SCFA. Therefore, whole milk can be incorporated into part of a cardio-protective diet. Regarding this, future studies may target SCFA to provide insight into more mechanistic views.

Abdominal aortic calcification: from ancient friend to modern foe

Background

Abdominal aortic calcifications were already ubiquitous in ancient populations from all continents. Although nowadays generally considered as an innocent end stage of stabilised atherosclerotic plaques, increasing evidence suggests that arterial calcifications contribute to cardiovascular risk. In this review we address abdominal aortic calcification from an evolutionary perspective and review the literature on histology, prevalence, risk factors, clinical outcomes and pharmacological interventions of abdominal aortic calcification.

Design

The design of this study was based on a literature review.

Methods

Pubmed and Embase were systematically searched for articles on abdominal aortic calcification and its synonyms without language restrictions. Articles with data on histology, prevalence, risk factors clinical outcomes and/or pharmacological interventions were selected.

Results

Abdominal aortic calcification is highly prevalent in the general population and prevalence and extent increase with age. Prevalence and risk factors differ between males and females and different ethnicities. Risk factors include traditional cardiovascular risk factors and decreased bone mineral density. Abdominal aortic calcification is shown to contribute to arterial stiffness and is a strong predictor of cardiovascular events and mortality. Several therapies to inhibit arterial calcification have been developed and investigated in small clinical trials.

Conclusions

Abdominal aortic calcification is from all eras and increasingly acknowledged as an independent contributor to cardiovascular disease. Large studies with long follow-up must be carried out to show whether inhibition of abdominal aortic calcification will further reduce cardiovascular risk.

Association between pulse pressure and aortic calcification: Findings from the National Health and Nutrition Examination Survey 2013-2014

Dual-energy X-ray absorptiometry (DXA) is a low-cost, minimal radiation technique commonly used to assess bone density and body composition that can also provide a measure of abdominal aortic calcification (AAC). We examined the association between pulse pressure (PP) and DXA-derived AAC in a nationally representative sample of US adults. Analyses were performed in 2,478 adults from the 2013-2014 NHANES cycle. AAC scores were calculated using a validated 24-point scale from thoraco-lumbar spine images (scored 1-6 across four vertebral heights from L1-L4 for both anterior and posterior aortic walls). We examined PP as a predictor of both the presence (dichotomous) and magnitude (continuous) of AAC in age-stratified analyses (<60 years of age and ≥60 years of age) adjusting for traditional cardiovascular disease risk factors, sex, mean arterial pressure and additionally for age and antihypertensive medication. The prevalence of AAC was 25.5%. PP was a predictor of the presence of AAC in fully adjusted models in adults <60 years of age (OR 1.31, P < .05) and ≥60 years of age (OR 1.33, P < .05). PP was also associated with the magnitude of AAC in the overall sample but did not retain significance after separating by age-groups and additionally adjusting for antihypertensive medication. In conclusion, PP is associated with the presence of AAC as measured by DXA in a nationally representative sample of US adults.

The association between heart rhythm complexity and the severity of abdominal aorta calcification in peritoneal dialysis patients

Abdominal aorta calcification (AAC) has been associated with clinical outcomes in peritoneal dialysis (PD) patients. Heart rhythm complexity analysis has been shown to be a promising tool to predict outcomes in patients with cardiovascular disease. In this study, we aimed to analyze the association between heart rhythm complexity and AAC in PD patients. We prospectively analyzed 133 PD patients. Heart rhythm complexity including detrended fluctuation analysis and multiscale entropy was performed. In linear analysis, the patients in the higher AAC group (AAC ≥15%) had a significantly lower standard deviation of normal RR intervals, very low frequency, low frequency, high frequency and low/high frequency ratio. In non-linear analysis, DFAα1, slope 1–5, scale 5 and area 6–20 were significantly lower in the patients with higher AAC. Receiver operating characteristic curve analysis showed that DFAα1 had the greatest discriminatory power to differentiate these two groups. Multivariate logistic regression analysis showed that DFAα1 and HbA1c were significantly associated with higher AAC ratio. Adding DFAα1 significantly improved the discriminatory power of the linear parameters in both net reclassification improvement and integrated discrimination improvement models. In conclusion, DFAα1 is highly associated with AAC and a potential cardiovascular marker in PD patients.

Gender difference in the relationship between uric acid and pulse pressure among Korean adults

Hyperuricemia is associated with cardiovascular disease, but the relationship between uric acid (UA) and pulse pressure (PP) is unclear. Therefore, the present study assesses the relationship between UA and PP among Korean adults. Data from 6,310 subjects (2,800 men and 3,510 women) in the seventh Korean National Health and Nutrition Examination Survey (2016) were analyzed. After adjusting for related variables, the odds ratios (ORs) of hyperuricemia (UA ≥ 7.0 mg/dL in men or ≥ 6.0 mg/dL in women) in the high PP group (PP > 65.0 mmHg) in overall populations (OR, 1.563; 95% confidence interval [CI], 1.144-2.136) and women (OR, 1.631; 95% CI, 1.046-2.544) were significantly higher than those in normal PP, but not in men (OR, 1.309; 95% CI, 0.840-2.040). In conclusion, uric acid was positively associated with pulse pressure in women, but not in men.

Diabetes and Abdominal Aortic Calcification-a Systematic Review

PURPOSE OF REVIEW

A systematic literature review was performed to evaluate diabetes mellitus (DM) as a risk factor of abdominal aortic calcification (AAC), and address factors that might contribute to the development of AAC in DM patients.

RECENT FINDINGS

DM is an independent risk factor of AAC development. Bone metabolism along with lifestyle factors among DM patients makes them more prone to AAC. Hip and vertebral fractures, high phosphate, smoking, hypertension, and low osteocalcin could make DM patients prone to AAC. Low levels of high-density lipoprotein (HDL), high low-density lipoprotein (LDL), high total cholesterol/HDL ratio, low bone mineral density (BMD) may be risk factors, but the literature is more ambiguous. Body mass index (BMI) does not appear to increase risk of AAC. High phosphate levels and low osteocalcin levels seem to be biomarkers of AAC in patients with diabetes. However, the association between DM and AAC is complicated.

Prevalence and clinical characteristics of pseudohypertension in elderly patients prepared for coronary artery angiography

BACKGROUND

Pseudohypertension (PHT) can cause adverse effects in the elderly owing to administration of antihypertension therapy. The present study aimed to determine the prevalence of PHT in the elderly and associated risk factors to investigate a noninvasive method of detection of PHT.

METHODS

We recruited 151 patients (age ≥60 years) who underwent coronary angiography. Demographic and clinical data were collected from the patients. During coronary angiography, intrabrachial arterial pressure and indirect blood pressure were measured. Brachial-ankle pulse wave velocity (ba-PWV) was measured within 2 weeks after coronary angiography.

RESULTS

Based on the differences between the direct and indirect pressure measurements, the patients were divided into a PHT group (n = 87) and a non-PHT group (n = 64). The prevalence of PHT was 57.6%, and the development of PHT was significantly associated with older age. Serum creatinine level and creatinine clearance rate were significantly higher in the non-PHT group than in the PHT group (P < .05). In addition, the PHT group had significantly higher ba-PWV and pulse pressure (PP) than the non-PHT group (P < .05). Receiver-operating characteristic curve analysis revealed that ba-PWV (AUC = 0.783) and PP (AUC = 0.791) showed a relatively good diagnostic performance for PHT.

CONCLUSIONS

PHT was present in most of the elderly who had indications for coronary angiography and associated with age and renal function. The data from the present study also suggested that both PP and ba-PWV could be used to positively predict PHT.

Abdominal aortic calcification on dual-energy X-ray absorptiometry: Methods of assessment and clinical significance

Abdominal aortic calcification (AAC) can be accurately recognized on lateral spine images intended for vertebral fracture assessment, that are obtained with dual-energy X-ray absorptiometry (DXA). Greater amounts of AAC are common in the older population for whom DXA is routinely done, and have been consistently associated with incident atherosclerotic cardiovascular disease (ASCVD) events. AAC has also been associated with incident fractures in some prospective studies, but not in others. However, further research is needed to quantify the extent to which measurement of AAC improves prediction of ASCVD events and its impact on physician and patient ASCVD risk management. Additionally, research to develop better, more precise, automated, quantitative methods of AAC assessment on lateral spine densitometric images will hopefully lead to better prediction of clinical outcomes. In conclusion, although the prime indication for densitometric lateral spine imaging remains vertebral fracture assessment, AAC that is found incidentally on lateral spine images should be reported, so that patients and their health care providers are aware of its presence.

The Relationship Between Pulse Pressure, the Estimated Glomerular Filtration Rate, and Urine Microalbumin/Creatinine Ratio in Korean Adults

BACKGROUND/AIMS

Pulse pressure (PP) is a predictor of adverse outcomes in patients on haemodialysis. Thus, the present study was conducted to assess the relationship between PP, estimated glomerular filtration rate (eGFR), and urine microalbumin/creatinine ratio (uACR) in Korean adults.

METHODS

Data of 9,409 adults (4,206 men and 5,203 women) aged ≥ 20 years from the Sixth Korean National Health and Nutrition Examination Survey (2013-2014) were analyzed.

RESULTS

A multivariate analysis revealed that systolic blood pressure (SBP) (β = -0.170, 95% confidence interval [CI], -0.216 to -0.159), diastolic blood pressure (DBP) (β = 0.088, 95% CI 0.108-0.200; p < 0.001), and PP (β = -0.134, 95% CI -0.215 to -0.157) were significant factors determining eGFR. In contrast, SBP (β = 0.152, 95% CI, 0.985-1.456; p < 0.001), DBP (β = -0.062, 95% CI -1.141 to -0.442; p < 0.001), and PP (β = 0.118, 95% CI 0.965-1.436; p < 0.001) were the significant factors determining uACR. The odds ratios (ORs) of a high PP (PP ≥ 60 mmHg) with a normal group [eGFR ≥ 60 ml/min/1.73 m2 and uACR < 30 mg/g] as a reference were significant for decreased eGFR [eGFR < 60 ml/min/1.73 m2, 1.484 (95% CI, 1.003-2.196)], elevated uACR [uACR ≥ 30 mg/g, 2.592 (95% CI, 2.085-3.223)], and decreased eGFR plus elevated uACR [eGFR < 60 ml/min/1.73 m2 and uACR ≥ 30 mg/g, 3.889 (95% CI, 2.519-6.004)].

CONCLUSION

Enhanced PP was associated with a decreased eGFR and an increase in uACR in Korean adults. In addition, the PP increased greatly when a decrease in eGFR and an increase in uACR appeared simultaneously.

Influence of Differential Calcification in the Descending Thoracic Aorta on Aortic Pulse Pressure

Purpose

Multiple studies have shown pulse pressure (PP) to be a strong predictor of aortic calcification. However, no studies are available that correlate PP with aortic calcification at the segmental level.

Methods

We identified 37 patients with aortic PP measured during cardiac catheterization. Their noncontrast chest computed tomography scans were evaluated for the presence of calcium in different segments (ascending aorta, arch of aorta [arch], descending aorta) and quantified. Patients with calcification (Calcified Group A) were compared against patients without calcification (Noncalcified Group B) in terms of PP, calcification and compliance.

Results

The mean of the total calcium score was higher in the descending aorta than the arch or ascending aorta (691 vs 571 vs 131, respectively, P<0.0001). PP had the strongest correlation with calcification in the descending aorta (r=0.47, P=0.004). Calcified Group A had a much higher PP than Noncalcified Group B, with the greatest difference in the descending aorta (20 mmHg, P<0.0001), lesser in the ascending aorta (10 mmHg, P=0.12) and the least in the arch (5 mmHg, P=0.38). Calcified Group A patients also had much lower compliance than Noncalcified Group B patients, with the greatest difference among groups seen in the descending aorta (0.7 mL/mmHg, P=0.002), followed by the ascending aorta, then arch.

Conclusions

These are the first data to evaluate the relative impact of aortic segments in PP. Finding the greatest amount of calcification along with greatest change in PP and compliance in the descending aorta makes a case that the descending aorta plays a major role in PP as compared to other segments of the thoracic aorta.

Upper Extremity Pulse Pressure Predicts Amputation-Free Survival after Lower Extremity Bypass

Increased pulse pressure reflects pathologic arterial stiffening and predicts cardiovascular events and mortality. The effect of pulse pressure on outcomes in lower extremity bypass patients remains unknown. We thus investigated whether preoperative pulse pressure could predict amputation-free survival in patients undergoing lower extremity bypass for atherosclerotic occlusive disease. An institutional database identified 240 included patients undergoing lower extremity bypass from 2005 to 2014. Preoperative demographics, cardiovascular risk factors, operative factors, and systolic and diastolic blood pressures were recorded, and compared between patients with pulse pressures above and below 80 mm Hg. Factors were analyzed in bi- and multivariable models to assess independent predictors of amputation-free survival. Kaplan-Meier analysis was performed to evaluate the temporal effect of pulse pressure ≥80 mm Hg on amputation-free survival. Patients with a pulse pressure ≥80 mm Hg were older, male, and had higher systolic and lower diastolic pressures. Patients with pulse pressure <80 mm Hg demonstrated a survival advantage on Kaplan-Meier analysis at six months (log-rank P = 0.003) and one year (P = 0.005) postoperatively. In multivariable analysis, independent risk factors for decreased amputation-free survival at six months included nonwhite race, tissue loss, infrapopliteal target, and preoperative pulse pressure ≥80 mm Hg (hazard ratio 2.60; P = 0.02), while only tissue loss and pulse pressure ≥80 mm Hg (hazard ratio 2.30, P = 0.02) remained predictive at one year. Increased pulse pressure is independently associated with decreased amputation-free survival in patients undergoing lower extremity bypass. Further efforts to understand the relationship between increased arterial stiffness and poor outcomes in these patients are needed.

Are frailty markers associated with serious thoracic and spinal injuries among motor vehicle crash occupants?

BACKGROUND

While age is a known risk factor in trauma, markers of frailty are growing in their use in the critically ill. Frailty markers may reflect underlying strength and function more than chronologic age, as many modern elderly patients are quite active. However, the optimal markers of frailty are unknown.

METHODS

A retrospective review of The Crash Injury Research and Engineering Network (CIREN) database was performed over an 11-year period. Computed tomographic images were analyzed for multiple frailty markers, including sarcopenia determined by psoas muscle area, osteopenia determined by Hounsfield units (HU) of lumbar vertebrae, and vascular disease determined by aortic calcification.

RESULTS

Overall, 202 patients were included in the review, with a mean age of 58.5 years. Median Injury Severity Score was 17. Sarcopenia was associated with severe thoracic injury (62.9% vs. 42.5%; p = 0.03). In multivariable analysis controlling for crash severity, sarcopenia remained associated with severe thoracic injury (p = 0.007) and osteopenia was associated with severe spine injury (p = 0.05). While age was not significant in either multivariable analysis, the association of sarcopenia and osteopenia with development of serious injury was more common with older age.

CONCLUSIONS

Multiple markers of frailty were associated with severe injury. Frailty may more reflect underlying physiology and injury severity than age, although age is associated with frailty.

LEVEL OF EVIDENCE

Prognostic and epidemiologic study, level IV.

Impact of Renal Functional/Morphological Dynamics on the Calcification of Coronary and Abdominal Arteries in Patients with Chronic Kidney Disease

Aim: Fast-progressing vascular calcification (VC) is accompanied by renal atrophy and functional deterioration along with atherosclerosis in patients with chronic kidney disease (CKD). However, the relationship between VC progression and renal functional and/or morphological changes remains unclear.

Methods: We included 70 asymptomatic patients with CKD without hemodialysis in our study. To identify temporal variations, the coronary artery calcification score (CACS), abdominal aortic calcification index (ACI), and renal parenchymal volume index (RPVI) were determined via spiral computed tomography scans taken during the study. We investigated significant factors related to annualized variations of CACS (ΔCACS/y) and ACI (ΔACI/y).

Results: During the follow-up period (4.6 years), median values of CACS [in Agatston units (AU)] and ACI increased from 40.2 to 113.3 AU (p = 0.053) and from 13.2 to 21.7% (p = 0.036), respectively. Multivariate analysis revealed that CACS at baseline (p < 0.001) and diabetes mellitus (DM) status (p = 0.037) for ΔCACS/y and ACI at baseline (p = 0.017) and hypertension (HT) status (p = 0.046) for ΔACI/y were significant independent predictors. Furthermore, annualized RPVI variation was significantly related to both ΔCACS/y and ΔACI/y (R = −0.565, p < 0.001, and R = −0.289, p = 0.015, respectively). On the other hand, independent contributions of the estimated glomerular filtration rate (eGFR) and annualized eGFR variation to VC progression were not confirmed.

Conclusion: The degree of VC at baseline, DM, HT, and changes in renal volume, but not eGFR, had a strong impact on VC progression in patients with CKD.

Predictors of abdominal aortic calcification progression in patients with chronic kidney disease without hemodialysis

BACKGROUND AND AIMS

Abdominal aortic calcification (AAC) is an important predictor of cardiovascular mortality in patients with chronic kidney disease (CKD). However, little is known regarding AAC progression in these patients. This study aimed to identify risk factors associated with AAC progression in patients with CKD without hemodialysis.

METHODS

We recruited 141 asymptomatic patients with CKD without hemodialysis [median estimated glomerular filtration rate (eGFR), 40.3 mL/min/1.73 m²] and evaluated the progression of the abdominal aortic calcification index (ACI) over 3 years. To identify risk factors contributing to the rate of ACI progression, the associations between baseline clinical characteristics and annual change in ACI for each CKD category were analyzed. The annual change of ACI (ΔACI/year) was calculated as follows: (second ACI - first ACI)/duration between the two evaluations.

RESULTS

Median ΔACI/year values significantly increased in advanced CKD stages (0.73%, 0.87%, and 2.24%/year for CKD stages G1-2, G3, and G4-5, respectively; p for trend = 0.041). The only independent risk factor for AAC progression in mild to moderate CKD (G1-3, eGFR ≥ 30 mL/min/1.73 m²) was pulse pressure level (β = 0.258, p = 0.012). In contrast, parathyroid hormone (PTH) level was significantly correlated with ΔACI/year (β = 0.426, p = 0.007) among patients with advanced CKD (G4-5, eGFR < 30 mL/min/1.73 m²).

CONCLUSIONS

This study suggests that the AAC progression rate was significantly accelerated in patients with advanced CKD. In addition, measuring PTH is useful to evaluate both bone turnover and AAC progression in patients with advanced CKD.

Colorectal anastomotic leakage can be predicted by abdominal aortic calcification on preoperative CT scans: A pilot study

BACKGROUND

There have been no solid data regarding whether patients with aortic calcification (AC) who have undergone colorectal surgery are at increased risk for anastomotic leakage. Our study aim to investigate the impact of AC on anastomotic leakage (AL) and postoperative morbidity after colorectal resection.

METHODS

This was a cohort study of 60 patients who were prospectively registered in a database. We evaluated the relationship between an aortic calcification score (ACS), measured on preoperative computed tomography (CT) imaging, and surgical complications in patients undergoing colorectal surgery.

RESULTS

ACS was strongly correlated with mortality rate. All three of the deceased patients were in the ACS-2 group (5%; P=0.021). The rate of AL was positively correlated with ACS; no leakage was found cases of ACS-0, with a rate of 18% in cases of ACS-1 and 44% in cases of ACS-2 (P=0.022). The consequences of AL were more serious according to the grade of ACS.

DISCUSSION

This study suggested that aortic calcification score is correlated with surgical outcomes, particularly anastomosis leakage, after colorectal surgery. These findings could provide useful tools for adapting surgical strategies by delaying colorectal anastomosis in high-risk patients.

Protective Effect of Myo-Inositol Hexaphosphate (Phytate) on Abdominal Aortic Calcification in Patients With Chronic Kidney Disease

OBJECTIVE

The aim of this study was to evaluate the relationship between physiological levels of myo-inositol hexaphosphate (phytate) and cardiovascular (CV) calcification in patients with chronic kidney disease (CKD).

DESIGN AND METHODS

This was a prospective cross-sectional study conducted from December 2012 to June 2013.

SUBJECTS

Sixty-nine consecutive patients with CKD who were not undergoing renal replacement therapy.

INTERVENTION

All subjects were given lateral lumbar X-rays to quantify abdominal aortic calcification (AAC). Clinical laboratory analyses and phytate food frequency questionnaires were also performed.

MAIN OUTCOME MEASURE

Phytate urinary excretion, estimated phytate consumption (based on food frequency questionnaire) and AAC score. Patients were divided into two groups based on median abdominal aortic calcification (AAC) score: no/mild AAC (AAC ≤ 6, n = 35) and moderate/severe AAC (AAC > 6, n = 34).

RESULTS

Patients with no/mild AAC were younger, had lower pulse pressure, greater dietary intake of phytate, greater urinary phytate and the prevalence of prior CV disease was significantly lower compared to patients with moderate/severe AAC. Among the top 10 phytate-rich foods, lentil consumption was significantly greater in patients with no/mild AAC than in those with moderate/severe AAC. Multivariate logistic regression analysis indicated that age, prior CV disease, urinary phytate (or lentil consumption) were independently associated to AAC.

CONCLUSION

Our results suggest that adequate consumption of phytate can prevent AAC in patients with CKD. Further prospective studies must be performed to elucidate the benefits of a phytate-rich diet and the associated risk of phosphorus bioavailability in these patients.

Abdominal aortic calcification: A reappraisal of epidemiological and pathophysiological data

In men and women, there is a significant association between the risk of cardiovascular event (myocardial infarction, stroke) and risk of major fragility fracture (hip, vertebra). Abdominal aortic calcification (AAC) can be assessed using semiquantitative scores on spine radiographs and spine scans obtained by DXA. Severe AAC is associated with higher risk of major cardiovascular event. Not only does severe AAC reflect poor cardiovascular health status, but also directly disturbs blood flow in the vascular system. Severe (but not mild or moderate) AAC is associated with lower bone mineral density (BMD), faster bone loss and higher risk of major fragility fracture. The fracture risk remains increased after adjustment for BMD and other potential risk factors. The association between severe AAC and fracture risk was found in both sexes, mainly in the follow-ups of less than 10years. Many factors contribute to initiation and progression of AAC: lifestyle, co-morbidities, inorganic ions, dyslipidemia, hormones, cytokines (e.g. inflammatory cytokines, RANKL), matrix vesicles, microRNAs, structural proteins (e.g. elastin), vitamin K-dependent proteins, and medications (e.g. vitamin K antagonists). Osteogenic transdifferentiation of vascular smooth muscle cells (VSMC) and circulating osteoprogenitors penetrating into vascular wall plays a major role in the AAC initiation and progression. Vitamin K-dependent proteins protect vascular tunica media against formation of calcified deposits (matrix GLA protein, GLA-rich protein) and against VSMC apoptosis (Gas6). Further studies are needed to investigate clinical utility of AAC for the assessment of fracture and cardiovascular risk at the individual level and develop new medications permitting to prevent AAC progression.

Osteoprotegerin, inflammation and dyslipidemia are associated with abdominal aortic calcification in non-diabetic patients on peritoneal dialysis

BACKGROUND AND AIMS

Abdominal aortic calcification (AC) has been reported to be associated with cardiovascular disease (CVD) in hemodialysis patients but is rarely discussed in peritoneal dialysis (PD) patients. We examined the independent predictors and predictive power for survival of AC in prevalent PD patients.

METHODS AND RESULTS

AC was detected by computed tomography (CT) and represented as the percentage of the total aortic cross-section area affected by AC (%AC). The predictors of %AC ≥ 15 were examined by multiple logistic regression analysis. Cox proportional hazard analysis was used to determine the hazard ratios associated with high %AC. A total of 183 PD patients were recruited to receive CT scans and divided into group 1 (%AC < 15, n = 97), group 2 (%AC ≥ 15, n = 41), and group 3 (diabetic patients, n = 45). Group 1 patients had lower osteoprotegerin (OPG) levels than group 2 patients (798 ± 378 vs. 1308 ± 1350 pg/mL, p < 0.05). The independent predictors for %AC ≥ 15 included the atherogenic index, OPG, and C-reactive protein (CRP). The age-adjusted hazard ratios associated with %AC ≥ 15 were 3.46 (p = 0.043) for mortality and 1.90 (p = 0.007) for hospitalization.

CONCLUSIONS

%AC can predict mortality and morbidity in non-diabetic PD patients, and 15% is a good cut-off value for such predictions. There are complex associations among mineral metabolism, inflammation, and dyslipidemia in the pathogenesis of AC.

Glycosaminoglycan overproduction in the aorta increases aortic calcification in murine chronic kidney disease

Background

Vascular calcification accompanying chronic kidney disease increases the mortality and morbidity associated with cardiovascular disorders, but no effective therapy is available. We hypothesized that glycosaminoglycans may contribute to osteoblastic differentiation of vascular smooth muscle cells during vascular calcification.

Methods and Results

We used exostosin‐like glycosyltranferase 2–deficient (EXTL2 knockout) mice expressing high levels of glycosaminoglycans in several organs including the aorta. We performed 5/6 subtotal nephrectomy and fed the mice a high‐phosphate diet to induce chronic kidney disease. Overexpression of glycosaminoglycans in the aorta enhanced aortic calcification in chronic kidney disease in EXTL2 knockout mice. Ex vivo and in vitro, matrix mineralization in aortic rings and vascular smooth muscle cells of EXTL2 knockout mice was augmented. Furthermore, removal of glycosaminoglycans in EXTL2 knockout and wild‐type mice‐derived vascular smooth muscle cells effectively suppressed calcium deposition in a high‐phosphate environment.

Conclusions

These results illustrate an important role for glycosaminoglycans in the development of vascular calcification. Manipulation of glycosaminoglycan expression may have beneficial effects on the progression of vascular calcification in chronic kidney disease patients.

Cardiovascular disease in an adenine-induced model of chronic kidney disease: the temporal link between vascular calcification and haemodynamic consequences

OBJECTIVES

Medial vascular calcification is highly prevalent in chronic kidney disease (CKD), and it is a risk factor for mortality. This study characterizes the time course and the link between calcification of major arteries, changes in blood pressure (BP) and cardiac growth in experimental CKD.

METHODS

CKD (elevated serum creatinine and urea) was induced with a 0.25% adenine diet (5, 8 and 11 weeks). BP was measured by radiotelemetry in conscious rats or indwelling catheter under anaesthesia. At each time point, serum biochemistry and tissue calcification was quantified.

RESULTS

CKD was present in all animals by 5 weeks and the ensuing 6 weeks (11 weeks total). CKD animals developed elevated serum phosphate (5-8 weeks) and fibroblast growth factor-23 (FGF-23; 5-11 weeks) levels. There was a 100% incidence of calcification at 11 weeks, 71% at 8 weeks and 33% at 5 weeks, and distal arteries appeared more susceptible than proximal arteries. Calcification was associated with widening of pulse pressure (PP), and a higher pulse wave. Continuous radiotelemetry revealed a significant increase in SBP variability and an accelerated (<24 h) elevation in PP of at least 10 mmHg following 8 weeks of CKD. This precipitous change was driven by a drop in mean DBP rather than elevated mean SBP. PP, duration of CKD and FGF-23 levels correlated with left ventricular hypertrophy.

CONCLUSION

The unique haemodynamic consequences of medial calcification, combined with the hormonal consequences of hyperphosphatemia (i.e. FGF-23), seem to have an exacerbated risk for left ventricular hypertrophy.

An assessment of the relationship between excess fluoride intake from drinking water and essential hypertension in adults residing in fluoride endemic areas

In this study, the relationships between high water fluoride exposure and essential hypertension as well as plasma ET-1 levels were investigated. A total of 487 residents aged 40 to 75 were randomly recruited from eight villages in Zhaozhou County from Heilongjiang Province in China and were divided into 4 groups according to the concentrations of fluoride in their water. Consumption levels of drinking water fluoride for normal, mild, moderate, and high exposure groups were 0.84±0.26 mg/L, 1.55±0.22 mg/L, 2.49±0.30 mg/L, and 4.06±1.15 mg/L, respectively. The prevalence of hypertension in each group was 20.16%, 24.54%, 32.30%, and 49.23%, respectively. There were significant differences between all the groups; namely, with the increase in water fluoride concentrations, the risk of essential hypertension in adults grows in a concentration-dependent manner. Significant differences were observed in the plasma ET-1 levels between the different groups (P<0.0001). In the multivariable logistic regression model, high water fluoride concentrations (F(-)≥3.01 mg/L, OR(4/1)=2.84), age (OR(3/1)=2.63), and BMI (OR(2/1)=2.40, OR(3/1)=6.03) were closely associated with essential hypertension. In other words, the study not only confirmed the relationship between excess fluoride intake and essential hypertension in adults, but it also demonstrated that high levels of fluoride exposure in drinking water could increase plasma ET-1 levels in subjects living in fluoride endemic areas.

Calcium scoring in unenhanced and enhanced CT data of the aorta-iliacal arteries: impact of image acquisition, reconstruction, and analysis parameter settings

BACKGROUND

Several studies have been published on the matter of abdominal aortic and iliac calcifications and the association to clinical entities such as diabetes mellitus and renal failure. However, comparing of these studies is questionable since quantification methods for atherosclerosis differ.

PURPOSE

To evaluate the effect of image acquisition settings, reconstruction parameters, and analysis methods on calcium quantification in the abdominal aorta.

MATERIAL AND METHODS

Calcium scores were retrospectively determined on standardized abdominal CT scans of 15 patients. Two researchers obtained calcium scores with 10 different lower thresholds (LT) (130, 145, 160, 175, 200, 300, 400, 500, 600, 1000) in CT scans with and without contrast enhancement, with slice thicknesses (ST) varying between 2.0-5.0 mm for the non-contrast-enhanced series and between 1.0-5.0 mm for the contrast-enhanced series. In addition calcium scores obtained with two convolution kernels (B10f, B20f) were compared. Inter-observer variability was calculated.

RESULTS

Calcium scoring at higher STs is overestimated compared to smaller STs and this effect was more pronounced with increasing calcium loads. Concerning the convolution kernel, scores obtained with kernel B10f were overestimated compared to kernel B20f. Increase of LT resulted in a decrease of the calcium score and scoring in contrast-enhanced series resulted in higher scores compared to non-contrast-enhanced series. These effects are more apparent in patients with higher calcium loads. Calcium scoring reproducibility with the reference standard is limited for the aorta-iliac trajectory, whereas scoring with the remaining settings is reproducible.

CONCLUSION

Scores obtained with different settings cannot be compared. The inter-observer reproducibility was limited using the reference standard and practical difficulties were substantial. Scoring with higher LT, ST, and contrast enhancement is faster and has less practical difficulties.

Hypervolemia rather than arterial calcification and extracoronary atherosclerosis is the main determinant of pulse pressure in hemodialysis patients

INTRODUCTION

Pulse pressure (PP) has been reported as an independent predictor of cardiovascular mortality in hemodialysis patients. In this study, we aimed to investigate association of PP with echocardiographic and vascular structural changes such as atherosclerosis and arterial calcifications in HD patients.

PATIENTS AND METHODS

In this cross-sectional study, 108 chronic hemodialysis patients (49 male, 59 female, mean age: 46 ± 13 years) were included. Biochemical analyses, echocardiographic and high-resolution carotid Doppler examinations were done. Aortic wall and coronary artery calcifications were measured with electron beam computed tomography. The degree of carotid artery stenosis was measured at four different sites (communis, bulbus, interna and externa) in both carotid arteries.

RESULTS

PP was strongly correlated with systolic (r: 0.82) and diastolic (r: 0.33) blood pressure, left ventricular mass index (r: 0.58), left ventricle end diastolic diameter (r: 0.38) and weakly correlated with aortic wall calcification score (r: 0.26) and carotid plaque score (r: 0.27), but not with coronary artery calcification score. Patients with carotid plaque had higher PP than patients without plaque (50 ± 16 mmHg versus 44 ± 14 mmHg, P = 0.05). Patients were divided into three groups according to aortic wall calcification score. PP was significantly higher in patients with higher aortic wall calcification (54 ± 16 mmHg) than patients with lower aortic wall calcification (44 ± 15 mmHg, P = 0.04). However, on multivariate linear regression analysis for predicting PP, the only significant factor retained was left ventricle end diastolic diameter.

CONCLUSION

PP was weakly associated with large vessel calcification and atherosclerosis in hemodialysis patients. The bulk of the effect on PP seems to be due to hypervolemia.

Distribution of ankle—brachial index and the risk factors of peripheral artery disease in a multi-ethnic Asian population

Peripheral artery disease (PAD) is a manifestation of systemic atherosclerosis and is associated with increased cardiovascular morbidity and mortality. We describe the prevalence and risk factors of PAD in a multi-ethnic Asian population (Chinese, Malays and Indians) in Singapore. The Singapore Prospective Study Program recruited 4132 individuals between 2004 and 2006 in which the ankle—brachial index (ABI) was measured using the Smartdop™ 20EX bi-directional blood flow detector. PAD was defined as ≤ 0.9 and a high ABI > 1.4, with ABI 1.11—1.20 as reference. The mean age (SD) of individuals in the study was 49.9 (11.8) years, with 51.8% females. PAD was present in 4.3% of the population and a high ABI (> 1.4) was rare. Malays and Indians had a higher risk (especially in females). Compared to those with an ABI between 1.11 and 1.20, those with PAD were more likely to be of Malay and Indian ethnicity, female sex, with higher systolic blood pressure and pulse pressure, with increased prevalence of diabetes mellitus, hypertension, albuminuria and renal impairment, and with a past history of stroke. In conclusion, in this large multi-ethnic Asian population, we document the distribution and risk factor associations for PAD. PAD shows an ethnic distribution similar to that of coronary artery disease in Singapore, with differences in sex distribution. Apart from traditional vascular risk factors, pulse pressure, renal impairment and a past history of stroke are important determinants of PAD.

Blood pressure and vascular calcification

The aim of this study was to determine the associations between the presence and extent of calcified atherosclerosis in multiple vascular beds and systolic blood pressure, diastolic blood pressure, pulse pressure, mean arterial pressure, isolated systolic hypertension, and hypertension. A total of 9510 patients (42.5% women) underwent electron beam computed tomography scanning as part of a routine health maintenance screening. At the same visit, blood pressure was measured with the participant in the seated position using a mercury sphygmomanometer. Mean age was 58+/-11.4 years, and body mass index was 27.1+/-4.5. The prevalences of any calcification in the carotids, coronaries, subclavians, thoracic aorta, abdominal aorta, and iliacs were 31.9%, 57.2%, 31.7%, 37.0%, 54.3%, and 48.8%, respectively. In separate multivariable logistic models containing traditional cardiovascular disease risk factors, pulse pressure and systolic blood pressure were significantly associated with the presence of calcification in all of the vascular beds except the iliacs and subclavians, respectively, with pulse pressure having stronger magnitudes of the associations for most of the vascular beds. Age-stratified analyses indicated that these associations were stronger in those >60 years of age compared with subjects <60 years of age, and sex-stratified analyses demonstrated that men had a greater association compared with women. Also, the magnitudes of the associations for isolated systolic hypertension were, in general, larger than those for hypertension. Pulse pressure and isolated systolic hypertension are robust and important correlates for calcified atherosclerosis in different vascular beds. Isolated systolic hypertension may be clinically relevant in diagnosing or preventing calcified atherosclerosis.

Validity and usefulness of aortic arch calcification in chest X-ray

BACKGROUND

Arterial calcification is associated with cardiovascular (CV) disease, to be leading to vessel wall stiffness and causing the management of hemodynamics in the elderly more difficult. Here, we compared the extent of calcification in the aortic arch by reviewing chest X-rays to that in the abdominal aorta as assessed by more detailed examinations. In addition, the validity of the grading and the relationship of this useful grading to clinical risk factors were evaluated.

METHODS AND RESULTS

The extent of aortic arch calcification (AAC) on a postero-anterior plain chest X-ray was divided into four grades (0 to 3). First, AAC grade was assessed in patients who underwent two quantitative examinations for abdominal aortic calcification; lateral radiograph of lumbar spine and/or computer tomography, and was positively correlated with the abdominal aortic calcification level. Subsequently, AAC grade in 239 out-patients (115 men; mean age, 61.9 years) was also evaluated, and was 0, 1, 2, and 3 in 46%, 22%, 29%, and 4% of the population, respectively, was significantly associated with pulse pressure and intima-media thickness. AAC grade in patients with diabetes or renal dysfunction was significantly higher than in those without each risk, but there was no association with other risk factors. In addition, AAC grade was positively correlated with risk factor clustering.

CONCLUSION

Assessment of AAC detectable on a chest X-ray is very useful and its grade reflects the magnitude of calcified change in the whole aorta. In addition, AAC evaluation may provide supportive information for atherosclerotic risk stratification.

Association between different measures of blood pressure and coronary artery calcium in postmenopausal women

The aim of this study was to determine the magnitude and significance of the associations among coronary artery calcium (CAC) and systolic blood pressure, diastolic blood pressure, pulse pressure, and mean arterial pressure. Women 50 to 59 years of age at baseline in the Women's Health Initiative clinical trial of conjugated equine estrogen underwent computed tomography scanning of the chest after the end of the trial. Blood pressures were measured twice with the participant in the seated position using a conventional mercury sphygmomanometer. The study included 1064 women with a mean age of 55.1 (2.8) years. The prevalence of a CAC score >0, >or=10, and >100 was 47%, 39%, and 19%, respectively. There was a linear association between the log-odds of any CAC and systolic blood pressure, whereas there was a curvilinear and inverse association with diastolic blood pressure. For any value of diastolic blood pressure, the probability of CAC increased with higher levels of systolic blood pressure, whereas for any given value of systolic blood pressure, the probability of any CAC decreased with higher levels of diastolic blood pressure. Also, a pulse pressure >or=55 mm Hg was associated with a higher odds (1.95; 95% CI, 1.24 to 3.06) for having any CAC, whereas individuals with isolated systolic hypertension had a 73% higher odds for CAC >0 (95% CI, 1.03 to 2.90; P=0.04). In postmenopausal women, higher levels of pulse pressure and systolic blood pressure were strong determinants of CAC, whereas diastolic blood pressure was inversely related.

Association between arterial stiffness and cerebral white matter lesions in community-dwelling elderly subjects

The presence of cerebral white matter lesions (WMLs) on MRI is suggested to be a predictive factor for vascular dementia and stroke. To investigate the relationship between arterial stiffness and WMLs, we performed brain MRI to evaluate the presence of two subtypes of WML-periventricular hyperintensities (PVH) and deep white matter lesions (DWML)-and furthermore, determined the brachial-ankle pulse wave velocity (ba-PWV) as a marker of arterial stiffness in 132 elderly asymptomatic subjects (49 men and 83 women, 70.3+/-9.0 years). PVH and DWML were observed in 41 (31.0%) and 53 (40.2%) subjects, respectively. The ba-PWV values were significantly greater in subjects with PVH than in those without. DWML also tended to be associated with ba-PWV, but the correlation was not statistically significant. In multiple logistic regression analysis, age and decreased DBP were independently associated with PVH. ba-PWV was also detected as an independent factor for the appearance of PVH (adjusted odds ratio: 2.84, p=0.015) but not DWML. These results indicate that the increase in arterial stiffness contributes to the pathogenesis of PVH rather than DWML. Although further study is needed to clarify the difference between WML subtypes, our study suggests that the measurement of ba-PWV is a simple and useful tool for detecting cerebral arterial dysfunction.

Calcification of the thoracic aorta by spiral computed tomography among hypertensive patients: Associations and risk of ischemic cerebrovascular events

BACKGROUND

Calcium is often deposited in the aorta, but the associations and clinical implications of calcification of the aorta have not yet been elucidated.

METHODS

In a prospective cohort of 455 hypertensive patients with at least 1 additional risk factor for atherosclerosis that underwent dual slice spiral computed tomography of the chest for assessment of arterial calcification (mean age 65.7+/-5.8, range 52-80 years, 48% female), we assessed for calcifications of the ascending and descending aorta and their association with the risk of subsequent ischemic cerebrovascular events during 3-year follow-up.

RESULTS

Calcification of the ascending or descending aorta was present in 342 (75%) patients (60% calcification of the ascending aorta and 56% of the descending aorta). The main associations of calcification of the thoracic aorta were increasing age and the presence of coronary calcification, mitral annulus calcification, and aortic valve calcification. In a logistic regression model the main predictors of ischemic cerebrovascular events (n=27) during follow-up were the presence of severe calcification (thickness of > or = 5 mm) of the descending aorta (OR 4.9, 95%CI 1.8 to 13.5) and cigarette smoking (OR 2.8, 95%CI 1.1 to 6.7).

CONCLUSIONS

Calcification of the thoracic aorta is highly prevalent among women and men with hypertension, is age-related, and correlates with calcification of the coronary arteries and heart valves. Only severe calcification of the descending aorta is associated with subsequent ischemic cerebrovascular events, suggesting that calcification of the thoracic aorta is a marker of the burden of vascular disease.

Quantitative analysis of aortic atherosclerosis in Korean female: a necropsy study

To assess the regional difference and influence of the biological variables on atherosclerosis in female, we analyzed 7 segments of aorta (2 ascending, 3 thoracic, and 2 abdominal) from 90 superficially healthy Korean women (39+/-14 yr of age) who died from external causes. Tissue specimens were macroscopically examined and histopathologically divided into 7 grades for scoring (ATHERO, from 0=intact, to 6=thrombi formation). Lumen diameter (LD), wall thickness (WT), intima thickness (INT), and media thickness (MED) were obtained by computed morphometry. Atherosclerosis was common in the distal infrarenal (C2), proximal thoracic (B1), and proximal ascending (A1) segments. Total 95.6% of all subjects had atherosclerosis of variable degree in one or more segments, but an aneurysmal change was not found. The number of atherosclerotic segments and atherosclerosis score in the 7 segments increased with aging. However, the body size did not affect the aortic size and ATHERO. With aging, LD and INT of the A1, B1 and C2 increased (p<.00001); WT of the B1 and C2 increased (p<.01); and MED of C2 decreased (p<.01). LD and WT of the B1 and C2 (p<.05), INT of the A1, B1 and C2 (p<.00001) increased, and MED of C2 decreased (p<.01) with ATHERO. These data suggest that age is simple but a reliable parameter for estimating the progression of atherosclerosis.

Role of fibroblast growth factor-23 in peripheral vascular calcification in non-diabetic and diabetic hemodialysis patients

INTRODUCTION

Fibroblast growth factor (FGF) 23 is a recently identified circulating factor that regulates phosphate (Pi) metabolism. Since the derangement of Pi control is an important risk factor for vascular calcification, we investigated the importance of plasma FGF-23 in the development of vascular calcification in the aorta and peripheral artery in hemodialysis patients with and without diabetes mellitus (DM).

METHODS

Male hemodialysis patients with DM (n=32) and without DM (n=56) were examined. Plasma samples were obtained before the start of dialysis sessions, and the FGF-23 levels were determined by enzyme-linked immunosorbent assay. Roentgenography of the aorta and hand artery was performed, and visible vascular calcification was evaluated by one examiner, who was blinded to the patient characteristics.

RESULTS

In the 56 non-DM hemodialysis patients, vascular calcification was found in the hand artery in 5 patients (8.9%) and in the aorta in 23 patients (41.1%). These levels were significantly lower (p<0.05) than in the 32 DM patients, of whom, 19 (59.4%) and 21 (65.6%) had vascular calcification of the hand artery and aorta, respectively. Multiple regression analyses performed separately in the non-DM and DM patients showed that the plasma FGF-23 level, CaxPi product, and body weight are independent factors significantly associated with hand-artery calcification and that diastolic blood pressure is associated with aorta calcification in non-DM patients. In DM patients, the plasma FGF-23 level and hemodialysis duration emerged as independent factors associated with hand-artery calcification and diastolic blood pressure was associated with aorta calcification. The independent association of the plasma FGF-23 level with hand-artery calcification was retained in both non-DM and DM patients when adjusted for the CaxPi product.

CONCLUSION

Our findings show that the plasma FGF-23 level is an independent factor negatively associated with peripheral vascular calcification in the hand artery, but not in the aorta, in both male non-DM and DM hemodialysis patients, even when adjusted for the CaxPi product. This study raises the possibility that the plasma FGF-23 level may provide a reliable marker for Moenckeberg's medial calcification in male hemodialysis patients, independent of its regulatory effect on Pi metabolism.

Vascular calcification and renal osteodystrophy relationship in chronic kidney disease

Cardiovascular disease and stroke account for 60-70% of all deaths in patients with end-stage renal disease (ESRD), at a risk that is 10-20-fold the age- and sex-matched general population. There is also increased coronary artery calcification and increased cardiovascular mortality in chronic kidney disease (CKD) and dialysis patients compared with the general population. Bone is similarly abnormal in CKD. There is an increased incidence of low bone mass and fractures in dialysis patients compared with the general population. Furthermore, a hip fracture in a dialysis patient is associated with a doubling of the mortality observed in nondialysis patients with a hip fracture. These two problems may be linked, as cross-sectional studies have demonstrated an inverse relationship between osteoporosis and coronary artery calcification in the general population and in ESRD patients. In vitro and ex vivo, there is clear evidence that vascular calcification is an active cell-mediated process, made worse by disorders of mineral metabolism. Many factors known to be associated with cardiovascular disease in CKD patients can directly increase calcification in vitro. In addition, in CKD, there are many mechanisms by which bone may adversely affect vascular calcification including disorders of bone remodelling, altered secretion of parathyroid hormone (PTH), hyperphosphatemia, hypercalcaemia, use of calcium based binders, and excessive vitamin D therapy. The coexistence of vascular risk factors and abnormal bone represent a double threat to the well being of patients with CKD.

Differential pulse pressure response to various antihypertensive drug families

Pulse pressure (PP) is emerging as a major pressure predictor of cardiac disease. The study comprised 10 185 untreated patients with essential hypertension. A total of 5395 men and 4790 women 56+/-13 years old, with uncomplicated essential hypertension, after a 15-day washout period and after 6 months of antihypertensive monotherapy were included. All patients included in the final cohort were responders and had normalized their blood pressure. PP was decreased least with diuretics (-5 mm Hg) and most with angiotensin II receptor blockers (ARBs) and calcium antagonists (-15 mm Hg), followed by angiotensin-converting enzyme inhibitors (ACEI) (-12 mm Hg) alpha- and beta-blockers (-10 and -9 mm Hg), differentiating among antihypertensive classes (P<0.001). The magnitude of PP fall was related to the degree of left ventricular (LV) mass reduction (P<0.001), seen best with ARBs (r=0.42) and least with ACEIs (r=0.18). Of the antihypertensive medications used in everyday practice, PP decrease may be achieved best with ARBs and calcium antagonists, whereas diuretics confer poor response. PP was decreased least with diuretics (-5 mm Hg) and most with ARBs and calcium channel blockers (-15 mm Hg), followed by ACEI (-12 mm Hg) alpha- and beta-blockers (-10 and -9 mm Hg), differentiating among antihypertensive classes (P<0.001). Of the antihypertensive medications used in everyday practice, PP decrease may be achieved best with ARBs and calcium antagonists.

Can we improve cardiovascular risk prediction beyond risk equations in the physician's office?

BACKGROUND AND OBJECTIVES

Beyond a global estimation of the cardiovascular risk through the assessment of major risk factors and their integration in dedicated risk scales or equations, the use of specific markers provides additive prognostic information at an individual level, including predisposing factors, which are not included in the risk equations as well as the individual susceptibility to their long-term exposure. However, the majority of these markers require specific devices and skills, which are not widely available in primary care.

METHODS

Some clinical and/or "low-cost" parameters are shown to be valuable risk markers, and their use could refine the risk estimation in a physician's office. Several epidemiologic studies suggest the heart rate, the pulse pressure and the ankle-brachial index are effective cardiovascular risk markers. The arms systolic pressure asymmetry could also be a useful marker of risk.

RESULTS AND CONCLUSIONS

Through a general review, the authors evaluate the potential of these clinical markers, including their use in combination for more accurate risk determination.

Effect of diet and exercise on pulse pressure and cardiac function in morbid obesity: analysis of 24-hour ambulatory blood pressure

Blood pressure is a major risk factor for cardiovascular events, although the role of pulse pressure, an independent predictor of arterial stiffness, has recently been emphasized. This study examines the baseline relationship between body mass index (BMI) and blood pressure indexes in 215 obese African Americans enrolled in a diet-exercise program. The subject population was 77% female, with a mean +/- SD age of 46.7+/-10.7 years and a mean BMI of 42.5+/-7.5 kg/m2. In addition, the authors prospectively examined the effect of weight loss on cardiovascular parameters in a subset of 25 participants. The results show a closer significant correlation between pulse pressure and BMI (b=1.97 kgm-1; p=0.001) than between systolic blood pressure and BMI (b=1.58 kgm-1; p=0.020). After 3 months of diet and exercise, average reductions were as follows: BMI, 4.2 kg/m2 (p<0.01); systolic blood pressure, 7.2 mm Hg (p<0.01); pulse pressure, 4.8 mm Hg (p<0.01); and cardiac output, 975 mL/min (p<0.01). Compliance index increased by 0.1 mL/mm Hg/m2 (p=0.03). The results highlight the potential value to cardiovascular health of a modest reduction in body weight in obese individuals.

Importance of arterial pulse pressure as a predictor of coronary heart disease risk in PROCAM

AIMS

To investigate pulse pressure (PP) as an independent predictor of coronary heart disease (CHD) risk.

METHODS AND RESULTS

On the basis of a 10-year follow-up of 5389 men aged 35-65 at recruitment into PROCAM, we used a proportional hazards model to calculate the effect of systolic blood pressure (SBP), diastolic blood pressure (DBP), and PP on CHD risk after correcting for age, high-density lipoprotein cholesterol, LDL cholesterol, triglycerides, smoking, diabetes, and family history of premature CHD. Increases of 10 mmHg in DBP, SBP, and PP were associated with an increased CHD hazard ratio (HR) of approximately 10%. When the group was divided into the age groups <50, 50-59, and >59 years, this relationship was seen in the age group 50-59 years for DBP, SBP, and PP and in men aged > or =60 for PP only (25% increase in HR). Overall, CHD risk in men with PP > or =70 mmHg was more three times that of men with PP <50 mmHg. This increased risk was not apparent at age <50 years, was greatest at age >60 years, and was also present in men who were normotensive at recruitment (SBP < or =160 mmHg, DBP < or =95 mmHg).

CONCLUSION

In older European men, increased PP is an important independent determinant of coronary risk, even among those initially considered normotensive.

VITAMIN D IN HEALTH AND DISEASE: The Role of Vitamin D in Vascular Calcification in Chronic Kidney Disease

Vascular calcification is a significant cause of morbidity and mortality in patients with chronic kidney disease (CKD). Disorders of mineral metabolism are likely involved in the pathogenesis of vascular calcification. Calcitriol and its analogs are effective in suppressing parathyroid hormone levels in patients with secondary hyperparathyroidism and CKD, but experimental studies demonstrate that these drugs can act directly on vascular smooth muscle cells. In some in vitro studies and in animal models of CKD, calcitriol has induced vascular calcification. Newer analogs of vitamin D appear to be less likely to induce vascular calcification, although published data are scarce. However, there is really no clear evidence in dialysis patients that calcitriol or analog administration is directly responsible for the induction of vascular calcification. However, indirectly, by oversuppression of parathyroid hormone (PTH) and induction of a low-turnover bone disease state, or by increased calcium-phosphorus product, the administration of calcitriol or its analogs may contribute to vascular calcification in patients with CKD. However, prospective randomized trials in CKD patients are necessary to fully understand the impact of calcitriol and analog therapy on vascular calcification.

Pulse pressure is independently associated with sensorimotor peripheral neuropathy in patients with type 2 diabetes

OBJECTIVES

The mechanisms responsible for the onset and progression of sensorimotor peripheral neuropathy (SMPN) in type 2 diabetes remain largely unknown. Although a link between hypertension and SMPN has been observed, it is not clear which blood pressure (BP) component (i.e. systolic, SBP; diastolic, DBP; or pulse pressure, PP) is primarily involved. We sought to determine the relationship between BP components and parameters of nerve function in type 2 diabetes.

DESIGN

Cross-sectional study.

SETTING

Academic medical centre.

SUBJECTS

A total of 55 consecutive ambulatory patients with type 2 diabetes (age 62.6 +/-8.0 years, mean +/- SD).

INTERVENTIONS

Measurement of clinic BP and 10 neurophysiological parameters: motor nerve conduction velocity (NCV; median, ulnar, posterior tibial and peroneal nerve), sensory amplitude (AMP) and latency (LAT; median, ulnar and sural nerve).

RESULTS

Univariate analysis showed that age, diabetes duration, SBP and PP were negatively correlated with nerve function. Regression analysis showed that, after correcting for age, duration of diabetes, glycated haemoglobin, body mass index, microalbuminuria and SBP, PP was independently and negatively associated with NCV (median, P =0.011; ulnar, P = 0.001; peroneal, P = 0.006 and posterior tibial, P = 0.005) and signal AMP (ulnar, P = 0.027; sural, P = 0.055), and positively associated with signal LAT (median, P = 0.083; sural, P = 0.021). SBP was negatively associated with signal AMP (median, P = 0.012) and positively associated with LAT (ulnar, P = 0.018). By contrast, DBP failed to show any significant correlation with nerve function.

CONCLUSIONS

The PP is strongly associated with neurophysiological parameters of nerve function in patients with type 2 diabetes. This relationship is independent of traditional risk factors and other BP components.

Aortic calcification

OBJECTIVES

Vascular calcification is a complicating factor observed in advanced atherosclerosis. This review summarises the present knowledge regarding abdominal aortic calcification.

DESIGN

Literature review.

METHODS

A literature review was carried using MEDLINE and PUBMED with the search terms 'abdominal', 'aortic' and 'calcification'. Articles were assessed for data regarding mechanisms, measurement, risk factors and outcomes of aortic calcification.

RESULTS

Thirty relevant studies were identified. These demonstrated a positive correlation between abdominal aortic calcification and the following factors: older age, hypertension, and smoking. Further studies are required to critically assess other risk factors such as gender, diabetes mellitus and renal failure. Calcification of the abdominal aorta is associated with an increased risk of mortality, coronary heart disease and stroke.

CONCLUSION

Aortic calcification predicts an increased incidence of cardiovascular events, however, the reasons for this association requires further investigation. Accurate measurement of aortic calcification is likely to be increasingly used to determine the risk of cardiovascular events.

Inflammation and vascular calcification

Both vascular calcification and inflammation are common in patients with chronic kidney disease (CKD). In patients on dialysis, there is increased coronary artery and peripheral artery calcification compared to the general population. Both intimal (atherosclerotic) and medial calcification in CKD patients are associated with increased morbidity and mortality. Vascular calcification is an active cell-mediated process, and likely reflects a transformation of vascular smooth muscle cells to osteoblast-like cells. Pooled uremic serum can induce this transformation, but the mechanism by which it does so is not yet clear. Several mediators of inflammation such as oxidation, carbonyl stress, C-reactive protein, and cytokines may directly stimulate vascular calcification. In addition, inflammation itself reduces fetuin-A, a naturally occurring inhibitor of vascular calcification which binds excess mineral in serum. The combination of the acceleration of vascular calcification together with impaired defense mechanisms creates a uremic milieu primed for extra-osseous calcification.

Relation of the metabolic syndrome to calcified atherosclerotic plaque in the coronary arteries and aorta

The metabolic syndrome is a clustering of low levels of high-density lipoprotein cholesterol, hyperglycemia, high waist circumference, hypertension, and elevated triglycerides, and is associated with cardiovascular disease. Calcified atherosclerotic plaque in the coronary arteries (CAC), measured by cardiac tomographic scans, is a marker for atherosclerosis and relates to mortality. The investigators examined the relation of the metabolic syndrome, and each of its components, to the prevalence of CAC, measured from 2002 to 2004 in 3,166 white and African-American subjects in the National Heart, Lung, & Blood Institute Family Heart Study. Adjusting for age, race, center, smoking, and alcohol consumption, odds ratios and 95% confidence intervals (CI) for a CAC score >100 for subjects with metabolic syndrome were 1.7 (95% CI 1.3 to 2.3) for men and 1.6 (95% CI 1.2 to 2.1) for women. Associations were found for most of the components of the metabolic syndrome with CAC. Associations with the metabolic syndrome were similar for calcified atherosclerotic plaque in the abdominal aorta among 3,173 subjects, with adjusted odds ratios for a score >1,000 of 2.1 (95% CI 1.5 to 3.1) for men and 1.8 (95% CI 1.4 to 2.4) for women. We conclude that the metabolic syndrome and most of its components are associated with a higher prevalence of calcified atherosclerotic plaque in the coronary arteries and abdominal aorta in white and African-American men and women.

Vascular calcification: a stiff challenge for the nephrologist: does preventing bone disease cause arterial disease?

There has been an explosion of interest in vascular calcification in the last 5 years. Four key "germinal" findings have fallen onto very fertile soil. First, on the background of an increasing cardiovascular disease burden it has been found that at least cross-sectionally, and in a limited fashion prospectively, achieved dialysis plasma phosphate levels are linked to all-cause and cardiovascular mortality. Second, there are increasing reports of calcific uremic arteriolopathy in Australia and the United States. Third, we know know that the mechanical properties of the carotid artery, and the aorta, have a profound influence on survival for dialysis patients. Vascular calcification itself (as assessed by x-ray films and ultrasound) has been linked to aortic stiffness. Fourth, increasing numbers of studies are showing extremely extensive coronary artery calcification (CAC) in dialysis patients, even at a young age. From these apparently unlinked observations the following assertion has been posited-that in the widespread (over) use of calcium-containing oral phosphate binders (OPB) to prevent uremic osteodystrophy in our dialysis population we have unwittingly accelerated widespread uremic vasculopathy and thereby contributed to premature cardiovascular mortality. It is the purpose of this article to discuss vascular calcification (and particularly CAC) in dialysis patients as we understand it today. We will review the published series, with special reference to the Sevelamer Treat to Goal trial and also discuss the new Kidney Disease Outcome Quality Initiative (K-DOQI) guidelines on the use of phosphate binders in chronic kidney disease.