COPART Risk Score Predicts Long-term Mortality in Peripheral Arterial Occlusive Disease

Targeted multiplex proteomics for prediction of all-cause mortality during long-term follow-up in outpatients with peripheral arterial disease

BACKGROUND AND AIMS

Patients with peripheral arterial disease (PAD) are at high risk for fatal events. We aimed to investigate the ability among several serum proteins to predict all-cause mortality in outpatients with PAD.

METHODS

Consecutive outpatients with carotid and/or lower extremity PAD were included in the discovery cohort (n = 436), and subjects with PAD from a population-based sample in the validation cohort (n = 129). Blood samples were analyzed for 81 proteins by a proximity extension assay. The proteins best predicting incident all-cause mortality were identified using L₁-regularized Cox regression. The added value of the identified proteins to clinical risk markers was evaluated by Cox regression models and presented by the area under the receiver operator characteristics curves (AUC).

RESULTS

In the discovery cohort (mean age 70 years; 59% men), 195 died (4.8 events per 100 person-years) during a 10.3 years median follow-up. The clinical risk markers generated an AUC of 0.70 (95% confidence interval [95%CI] 0.65-0.76). The two serum protein biomarkers with best prediction of all-cause mortality were growth differentiation factor 15 and tumor necrosis factor-related apoptosis-inducing ligand receptor 2. Adding these proteins to the clinical risk markers significantly improved prediction (p < 0.001) and yielded an AUC of 0.76 (95%CI 0.71-0.80). A higher discriminatory performance was observed in the validation cohort (AUC 0.84; 95% CI 0.76-0.92).

CONCLUSIONS

In a large-sample targeted proteomics assay, we identified two proteins that improved risk prediction beyond the COPART risk score. The use of high-throughput proteomics assays may identify potential biomarkers for improved risk prediction in patients with PAD.

Development of a 3-Dimensional Prognostic Score for Patients With Symptomatic Peripheral Artery Disease: PAD3D Score

Peripheral artery disease (PAD) is a high-risk condition for cardiovascular (CV) events, but no specific prognosis assessment tool exists. We developed an individual risk score (PAD^3D) based on the combined predictive value for mortality, including (1) age, (2) severity of PAD, and (3) extent of atherosclerosis. Patients (n = 1310) with symptomatic PAD were followed up for a mean of 50 ± 26 months. The cohort was randomly subdivided into a test and validation cohort. All-cause and CV mortality were prospectively analyzed for PAD^3D score and in combination with classical risk factors. For the test and validation cohort (n = 655 each), all-cause and CV mortality were predicted (P < .001) by the PAD^3D score. Additional inclusion of classical risk factors did not increase discrimination compared with PAD^3D as "area under receiver-operating characteristic" curves were similar for both scores at any time point. Thus, the addition of the classical risk factors to PAD^3D did not further improve the prognostic value. The PAD^3D score provides a risk gradient of a 4.5-fold increase in all-cause and CV mortality. We developed a score for precise prediction of all-cause and CV mortality. The PAD^3D score promises to allow for personalized goals in risk intervention.

A nationwide cohort study of the role of CHADS2 score in predicting lower extremity amputation and death among patients with peripheral arterial occlusive disease

OBJECTIVES

The current study aimed to explore whether the CHADS₂ score was predictive of lower extremity amputation (LEA) and death in people with peripheral arterial occlusive disease (PAOD).

METHODS

This nationwide cohort came from Taiwan, with 16,888 PAOD patients, from 2000 through 2011, extracted from the Longitudinal Health Insurance Database 2000. Cox proportional hazard regression models were employed to identify the LEA and mortality risk according to CHADS₂ score. The discriminatory properties of the score in predicting the outcomes were quantified by the area under the receiver operating characteristic curve (AUROC) and the Cox C-index.

RESULTS

The AUROC of the CHADS₂ score in predicting LEA and death were 0.75 (95% CI = 0.73-0.77) and 0.70 (95% CI = 0.69-0.71), respectively. The CHADS₂ score had an acceptable stratification capacity for LEA (C-index = 0.79) and death (C-index = 0.76) based on Cox-regression analysis.

CONCLUSIONS

This study correlates the CHADS₂ score with risk of developing LEA and death in patients with PAOD. The acceptable discriminative power of the score diversifies its predictive role in this population.

Determination of Risk Factors and Establishment of a Prediction Model for Immediate Technical Failure during Endovascular Treatment of Femoropopliteal Occlusive Disease

BACKGROUND

For long femoropopliteal occlusive lesions, the immediate technical failure (ITF) of endovascular treatment (EVT) is relatively high. Therefore, this study aims to reveal risk factors and establish a prediction model of ITF of EVT in femoropopliteal occlusive disease (FPOD) patients based on preoperative clinical date that may be helpful to the clinical procedures.

METHODS

A retrospective analysis of 1,563 FPOD patients who underwent above-the-knee EVT was undertaken. Univariate analysis with chi-squared test was used to screen risk factors from preoperative clinical data. Multivariable analysis with logistic regression was used to generate a model for predicting the ITF rate of EVT, which was evaluated through the receiver operating characteristic curve and another independent cohort of 242 FPOD patients.

RESULTS

Risk factors for ITF during EVT in FPOD included age (>80 years, X₁), the absence of diabetes mellitus (X₂), low-density lipoprotein (>160 mg/dL, X₃), lesion calcification (X₄), lesion length (>20 cm, X₅), ostial occlusion of superficial femoral artery (SFA) (X₆), and SFA lesion involving the popliteal artery (X₇). A logistic regression model was established based on the equation: -6.504 + 1.236X₁ + 0.945X₂ + 1.406X₃ + 1.136X₄ + 1.059X₅ + 2.307X₆ + 2.194X₇. Scores were given to risk factors as follows: X₁ (yes = 12, no = 0), X₂ (yes = 9, no = 0), X₃ (yes = 14, no = 0), X₄ (yes = 11, no = 0), X₅ (yes = 11, no = 0), X₆ (yes = 23, no = 0), and X₇ (yes = 22, no = 0). We determined that the optimal comprehensive score for predicting EVT failure was 39, with a sensitivity of 0.847 and a specificity of 0.8. Among these 242 peripheral arterial disease patients, 12 of 14 patients who had failed EVT had a comprehensive score of >39.

CONCLUSIONS

We identified a number of risk factors of ITF during the above-the-knee EVT and established a prediction model that may be used for guidance in clinical practice.

COPART Risk Score, Endothelial Dysfunction, and Arterial Hypertension are Independent Risk Factors for Mortality in Claudicants

OBJECTIVE

The COPART risk score consists of six variables to assess the prognosis of PAOD patients. The flow mediated dilation (FMD) quantifies endothelial function. The aim of this study was to evaluate the mortality prediction of these two variables in a long-term observation of claudicants.

METHODS

184 consecutive claudicants were included in a prospective observational study over a median observation period of 7.9 (IQR 7.2-8.7) years. The endothelial function was assessed on the day of study inclusion using brachial FMD.

RESULTS

Three groups were assigned according to the COPART risk score: low risk (LR), n = 72 (39%); medium risk (MR), n = 59 (32%); and high risk (HR), n = 53 (29%). Overall survival rates differed among COPART risk score groups (p < .001, 5 year survival: LR group 83% [95% CI 74-92%]; MR group 73% [95% CI 62-84%]; HR group 57% [95% CI 43-70%]). Survivors had a significantly better median FMD than non-survivors (4.1% [IQR 1.2-6.4] vs. 1.3% [IQR 0.0-4.2]; p < .001). Also the FMD differed significantly among the three COPART risk groups (LR 4.0% [IQR 1.2-6.3], MR 2.3% [IQR 0.0-6.3], HR 1.7% [IQR 0.0-3.6]; p = .033). Finally, independent predictors for disease specific survival were COPART risk score (p = .033; MR group [HR 1.6], 95% CI 0.7-3.6; HR group [HR 2.7], 95% CI 1.2-5.8), FMD (p = .004; FMD ≤2.5 vs. >2.5, HR 2.6, 95% CI 1.4-4.9), and arterial hypertension (p = .039; HR 3.5, 95% CI 1.1-11.3).

CONCLUSIONS

COPART risk score, FMD, and arterial hypertension are independent long-term mortality predictors in this group of claudicants. The best mortality assessment is provided by including all three predictors.

The extent of atherosclerotic lesions in crural arteries predicts survival of patients with lower limb peripheral artery disease: A new classification of crural atherosclerosis

BACKGROUND AND AIMS

Several studies report correlation of ankle brachial index (ABI) values and mortality. However, no studies exist on the predictive value of anatomical distribution of atherosclerotic lesions and the extent of atherosclerosis at defined arterial segments on life expectancy. The aim of the present study was to evaluate the significance of both extent and localisation of atherosclerotic lesions to mid-term patient survival.

METHODS

Digital subtraction angiography (DSA) images of 887 consecutive patients admitted to the Department of Vascular Surgery at Turku University Hospital (Turku, Finland) were retrospectively analysed. Each angiography was classified according to the TASC II classification for aorto-iliac and femoro-popliteal segments, and a similar four-grade index was created for crural arteries. Patients were followed until 36-months post DSA.

RESULTS

During 36-month follow-up 295 (33%) deaths occurred. Death during follow-up was strongly associated with extensive crural disease, but not with extensive proximal disease (Crural Index III-IV, p = 0.044 and < 0.001, respectively). In a Cox regression analysis incorporating baseline variables, Crural Index IV and most severe atherosclerosis on crural vessels were the strongest predictors of poor prognosis (HR 2.20 95% CI 1.3-3.7, p = 0.003 and HR 2.45 95% CI 1.5-4.0, p < 0.001 respectively).

CONCLUSIONS

The extent of crural atherosclerosis is independently associated with poor mid term life expectancy. Therefore, a classification of the extent of crural atherosclerosis could serve as an indicator of mortality among PAD patients and aid in clinical decision making.