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The chronic kidney disease (CKD) mineral bone disorder syndrome encompasses a number of metabolic, bone as well as vascular abnormalities of which vascular calcification is a prominent feature. Several noninvasive imaging techniques provide physicians with useful prognostic information beyond traditional cardiovascular and CKD-specific risk factors. We review the most recent evidence on vascular calcification screening as a tool for risk stratification in CKD patients.Cardiovascular aging is accelerated and is associated with a poor prognosis in CKD patients. Numerous traditional and nontraditional risk factors have been associated with this outcome. Imaging markers and serological risk factors do not carry the same prognostic information. In fact, whereas serum biomarkers reflect the risk to which the individual is exposed at the time of measurement, imaging markers represent the cumulative result of prolonged exposure to one or multiple risk factors. As such, they have often been demonstrated to be better outcome predictors than serological markers. In some cases, imaging markers have been suggested as desirable targets of therapy or to guide treatment individualization.Recent evidence suggests that cardiovascular imaging allows for cardiovascular risk stratification and treatment individualization in CKD patients.

Background: The high incidence of cardiovascular events in HIV infected patients creates the important challenge of performing an accurate risk assessment and initiating treatment in the most appropriate patients. The new Pooled Equations (PE) recommended by the recent ACC/AHA guidelines have not been tested in HIV infected patients and compared with the older Framingham Risk Score (FRS). Method: Cohort of 2,550 HIV infected patients (34% women) followed prospectively for a total of 10,695 patient-years. We compared the 10-year risk of events of 7.5% with PE versus a FRS level of 6%, for the dual purpose of assessing the validity of the new algorithm in HIV and verify whether lowering the threshold of the older algorithm may be equivalent to the new method. Results: Mean age was 49.7+/-7 years, and mean HIV exposure was 16.6+/-6 years. Total follow-up was 10,695 patient-years and 67 non-fatal myocardial infarctions and 2 CV deaths were recorded. PE>7.5% and FRS>6% predicted (44/69 and 49/69) and missed (25/69 and 20/69) the same number of true events. The Net Reclassification Index showed that PE>7.5% is weaker than FRS>6% to predict events (7% fewer events predicted) but better to predict non-events (14% more cases predicted to not occur). Table 1 shows the recommendation for statin therapy according to PE and FRS compared to current clinical practice within our institution: the 2 algorithms were not superior to what is currently implemented at our institution. Conclusions: In HIV infected patients the new PE>7.5% algorithm performs similarly to a FRS>6% to predict events but is better than the older algorithm to predict non-events. Neither model is superior to clinical practice as a method to select patients who should receive risk reduction therapies. (p-value for comparison of recommended vs actual statin prescription)

Summary Background and objectives Calcification of the mitral and aortic valves is common in dialysis patients (CKD-5D). However, the prognostic significance of valvular calcification (VC) in CKD is not well established. Design, setting, participants, & measurements 144 adult CKD-5D patients underwent bidimensional echocardiography for qualitative assessment of VC and cardiac computed tomography (CT) for quantification of coronary artery calcium (CAC) and VC. The patients were followed for a median of 5.6 years for mortality from all causes. Results Overall, 38.2% of patients had mitral VC and 44.4% had aortic VC on echocardiography. Patients with VC were older and less likely to be African American; all other characteristics were similar between groups. The mortality rate of patients with calcification of either valve was higher than for patients without VC. After adjustment for age, gender, race, diabetes mellitus, and history of atherosclerotic disease, only mitral VC remained independently associated with all-cause mortality (hazard ratio [HR], 1.73; 95% confidence interval [CI], 1.03 to 2.91). Patients with calcification of both valves had a two-fold increased risk of death during follow-up compared with patients without VC (HR, 2.16; 95% CI, 1.14 to 4.08). A combined CT score of VC and CAC was strongly associated with all-cause mortality during follow-up (HR for highest versus lowest tertile, 2.21; 95% CI, 1.08 to 4.54). Conclusions VC is associated with a significantly increased risk for all-cause mortality in CKD-5D patients. These findings support the use of echocardiography for risk stratification in CKD-5D as recently suggested in the Kidney Disease Improving Global Outcomes guidelines.

Algorithms and equations to calculate risk of cardiovascular events, though very useful as an in-office tool to conduct a preliminary assessment demonstrate a limited ability to predict risk in the individual patient. This has favored the development of several imaging modalities for subclinical atherosclerosis such as imaging of coronary calcium by computed tomography.Arterial wall calcification is intimately associated with atherosclerosis development and is therefore an optimal marker of the presence of disease. The paradigm underlying the use of imaging technologies to identify subclinical disease is that the quantification of plaque burden may provide a better risk stratification approach for the individual patient than the currently available tools.The most recent evidence supports this approach as will be discussed in the current review.

To assess the effect of estimated glomerular filtration rate (eGFR) on in-hospital mortality in young (2 than for an old (OR: 4.75, CI: 4.14 – 5.45) or very old patient (OR: 3.50, CI: 2.50 – 4.89) with the same degree of renal insufficiency compared to similar age patients with eGFR≥60 ml/min/1.73m 2 (Figure ). While the impact of renal impairment is substantial in all age groups, severe reduction in eGFR is a worse prognostic factor for younger than older patients.

Mineral metabolism disorders are associated with coronary atherosclerosis and poor outcomes in chronic kidney disease (CKD) and cardiovascular disease (CVD) patients. A recent study suggested that elevated levels of serum phosphorus are associated with increased risk of CVD in subjects free from CKD and CVD. However, data suggest that the distribution of serum phosphorus differs by gender and it is not known whether phosphorus carries the same prognostic significance in men and in women. We tested the association of baseline serum phosphorus levels with incidence of CHD (myocardial infarction or fatal coronary disease) in 13,998 subjects 45 to 64 years old free of CHD, stroke, or CKD from the Atherosclerosis Risk in Communities (ARIC) study with public use data. The mean follow up was 12.5 years. Serum phosphorus was classified according to quintiles. Elevated phosphorus was significantly associated with age, female gender, smoking, hypercholesterolemia, and fibrinogen levels (p < 0.0001 for each), but was inversely associated with hypertension and not associated with estimated glomerular filtration rate (eGFR). We observed a j-shaped relationship of serum phosphorus with CHD among men but not among women. Compared to men in the 2nd quintile, men in the 1st quintile experienced a 30% increased rate of CHD (multivariable adj. HR: 1.30, 95% CI: 1.01, 1.68) while HRs increased incrementally from 1.17 (95% CI: 0.89, 1.54) to 1.51 (95% CI: 1.09, 2.09) from the 3rd through 5th quintiles. This relationship in men remained significant after adjustment for classic CVD risk factors and estimated GFR (table ). Among women, serum phosphorus was not significantly associated with CHD (table ). In conclusion, this study suggests a j-shaped association of serum phosphorus with CHD risk in men but not women free of CKD and CHD at baseline. Table