Predictors of Mortality in Patients with Lower Extremity Peripheral Arterial Disease: 5-Year Follow-up

Prognostic Factors and Models to Predict Mortality Outcomes in Patients with Peripheral Arterial Disease: A Systematic Review

OBJECTIVE

Predicting adverse outcomes in patients with peripheral arterial disease (PAD) is a complex task owing to the heterogeneity in patient and disease characteristics. This systematic review aimed to identify prognostic factors and prognostic models to predict mortality outcomes in patients with PAD Fontaine stage I - III or Rutherford category 0 - 4.

DATA SOURCES

PubMed, Embase, and Cochrane Database of Systematic Reviews were searched to identify studies examining individual prognostic factors or studies aiming to develop or validate a prognostic model for mortality outcomes in patients with PAD.

REVIEW METHODS

Information on study design, patient population, prognostic factors, and prognostic model characteristics was extracted, and risk of bias was evaluated.

RESULTS

Sixty nine studies investigated prognostic factors for mortality outcomes in PAD. Over 80 single prognostic factors were identified, with age as a predictor of death in most of the studies. Other common factors included sex, diabetes, and smoking status. Six studies had low risk of bias in all domains, and the remainder had an unclear or high risk of bias in at least one domain. Eight studies developed or validated a prognostic model. All models included age in their primary model, but not sex. All studies had similar discrimination levels of > 70%. Five of the studies on prognostic models had an overall high risk of bias, whereas two studies had an overall unclear risk of bias.

CONCLUSION

This systematic review shows that a large number of prognostic studies have been published, with heterogeneity in patient populations, outcomes, and risk of bias. Factors such as sex, age, diabetes, hypertension, and smoking are significant in predicting mortality risk among patients with PAD Fontaine stage I - III or Rutherford category 0 - 4.

The effect of successful lower extremity revascularization on aortic stiffness in patients with peripheral arterial disease

OBJECTIVE

Peripheral arterial disease (PAD) is a global health problem and associated with poor outcomes. It causes increased arterial stiffness. The association of PAD with aortic arterial stiffness was investigated in previous studies. However, there is limited data regarding the effect of peripheral revascularization on arterial stiffness. The aim of our study is to investigate the effect of peripheral revascularization on aortic stiffness parameters in patients with symptomatic PAD.

METHODS

A total of 48 patients with PAD who underwent peripheral revascularization were included in the study. Echocardiography was performed before and after the procedure, and aortic stiffness parameters were obtained by using aortic diameters and arterial blood pressure measurements.

RESULTS

Post-procedural aortic strain (5.1 [1.3-14] vs. 6.3 [2.8-6.3], p = 0.009) and aortic distensibility (0.2 [0.0-0.9] vs. 0.3 [0.1-1.1], p = 0.001) measurements were significantly increased compared to pre-procedural values. Patients were also compared according to the lesion laterality, site and treatment methods. It was found that the change in aortic strain (p = 0.031) and distensibility (p = 0.043) were significantly higher in unilateral lesion compared to bilateral lesion. Also, the change in aortic strain (p = 0.042) and distensibility (p = 0.033) were significantly higher in iliac site lesion compared to superficial femoral artery (SFA) site lesion. Moreover, the change in aortic strain was significantly higher (p = 0.013) in patients treated with stent compared to only balloon angioplasty.

CONCLUSION

Our study showed that successful percutaneous revascularization significantly reduced aortic stiffness in PAD. The change in aortic stiffness was significantly higher in unilateral lesions, iliac site lesions and stent-treated lesions.

Role of triglyceride glucose index in long-term mortality of patients with lower extremity arterial disease

Aim: This work was designed to explore the role of the triglyceride-glucose (TyG) index in the prediction of long-term mortality in patients with lower extremity artery disease (LEAD) undergoing endovascular revascularization. Methods: The records of 723 patients with symptomatic LEAD undergoing endovascular revascularization between January 2016 and December 2021, with long-term follow-up until December 2021, were analyzed. Results: The rate of long-term mortality was significantly higher among patients with high TyG index than patients with low TyG index. Conclusion: The TyG index is an independent predictor of long-term mortality in patients with LEAD undergoing endovascular revascularization.

Prevalence and determinants of peripheral arterial disease in children with nephrotic syndrome

Peripheral arterial disease (PAD) is the least studied complication of nephrotic syndrome (NS). Risk factors which predispose children with NS to developing PAD include hyperlipidaemia, hypertension and prolonged use of steroids. The development of PAD significantly increases the morbidity and mortality associated with NS as such children are prone to sudden cardiac death. The ankle brachial index (ABI) is a tool that has been proven to have high specificity and sensitivity in detecting PAD even in asymptomatic individuals. We aimed to determine the prevalence of PAD in children with NS and to identify risk factors that can independently predict its development. A comparative cross-sectional study was conducted involving 200 subjects (100 with NS and 100 apparently healthy comparative subjects that were matched for age, sex and socioeconomic class). Systolic blood pressures were measured in all limbs using the pocket Doppler machine (Norton Doppler scan machine). ABI was calculated as a ratio of ankle to arm systolic blood pressure. PAD was defined as ABI less than 0.9. The prevalence of PAD was significantly higher in children with NS than matched comparison group (44.0% vs 6.0%, p < 0.001). Average values of waist and hip circumference were significantly higher in subjects with PAD than those without PAD (61.68± 9.1cm and 67.6± 11.2 cm vs 57.03 ± 8.3cm and 65.60± 12.5cm respectively, p< 0.005). Serum lipids (triglyceride, very low density lipoprotein, total cholesterol and low density lipoprotein) were also significantly higher in subjects with PAD than those without PAD [106.65mg/dl (67.8–136.7) vs 45.72mg/dl (37.7–61.3), 21.33mg/dl (13.6–27.3) vs 9.14mg/dl (7.5–12.3), 164.43mg/dl (136.1–259.6) vs 120.72mg/dl (111.1–142.1) and 93.29mg/dl (63.5–157.3) vs 61.84mg/dl (32.6–83.1), respectively p< 0.05]. Increasing duration since diagnosis of NS, having a steroid resistant NS and increasing cumulative steroid dose were independent predictors of PAD in children with NS; p< 0.05 respectively. With these findings, it is recommended that screening for PAD in children with NS should be done to prevent cardiovascular complications before they arise.

Gait variability is affected more by peripheral artery disease than by vascular occlusion

Background

Patients with peripheral artery disease with intermittent claudication (PAD-IC) have altered gait variability from the first step they take, well before the onset of claudication pain. The mechanisms underlying these gait alterations are poorly understood.

Aims

To determine the effect of reduced blood flow on gait variability by comparing healthy older controls and patients with PAD-IC. We also determined the diagnostic value of gait variability parameters to identify the presence of PAD.

Methods

A cross-sectional cohort design was used. Thirty healthy older controls and thirty patients with PAD-IC walked on a treadmill at their self-selected speed in pain free walking (normal walking for healthy older controls; prior to claudication onset for PAD) and reduced blood flow (post vascular occlusion with thigh tourniquet for healthy older controls; pain for PAD) conditions. Gait variability was assessed using the largest Lyapunov exponent, approximate entropy, standard deviation, and coefficient of variation of ankle, knee, and hip joints range of motion. Receiver operating characteristics curve analyses of the pain free walking condition were performed to determine the optimal cut-off values for separating individuals with PAD-IC from those without PAD-IC.

Results and discussion

Patients with PAD-IC have increased amount of variability for knee and hip ranges of motion compared with the healthy older control group. Regarding the main effect of condition, reduced blood flow demonstrated increased amount of variability compared with pain free walking. Significant interactions between group and condition at the ankle show increased values for temporal structure of variability, but a similar amount of variability in the reduced blood flow condition. This demonstrates subtle interactions in the movement patterns remain distinct between PAD-IC versus healthy older controls during the reduced blood flow condition. A combination of gait variability parameters correctly identifies PAD-IC disease 70% of the time or more.

Conclusions

Gait variability is affected both by PAD and by the mechanical induction of reduced blood flow. Gait variability parameters have potential diagnostic ability, as some measures had 90.0% probability of correctly identifying patients with PAD-IC.

Association of chronic kidney disease categories defined with different formulae with major adverse events in patients with peripheral vascular disease

OBJECTIVE

The aim of this study was to compare the ability of eGFR calculated by modification of diet in renal disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Lund-Malmö formulae in predicting major adverse events in peripheral vascular disease (PVD) patients.

METHODS

We prospectively recruited 2137 patients, measured serum creatinine to calculate eGFR using three different formulae and grouped patients into eGFR categories ≥90, 60-89, 45-59, 30-44, 15-29 and <15 ml/min/1.73 m(2). Patients were followed up for a median of 1.3 (inter-quartile range 0.3-3.6) years. The primary outcome was the combined incidence of myocardial infarction, stroke or death. The ability of eGFR categories defined with the different formulae to predict outcome was assessed using the net reclassification index.

RESULTS

1450 (67.9%), 1515 (70.9%) and 1813 (84.8%) patients had eGFR <90 ml/min/1.73 m(2) according to the CKD-EPI, MDRD and Lund-Malmö formulae, respectively. Using the CKD-EPI formula 276 (12.9%) patients were reclassified to a different eGFR category in comparison to the MDRD formula and the prediction of outcome was improved (net reclassification index 0.106, p < 0.001). Using the Lund-Malmö formula 563 (26.3%) patients were reclassified to a different eGFR category in comparison to the MDRD formula and the prediction of outcome was improved (net reclassification index 0.108, p < 0.001). Classification using the CKD-EPI and Lund-Malmö formulae was equally effective at predicting outcome (net reclassification index - 0.002, p = 0.397).

CONCLUSIONS

eGFR categories determined with the CKD-EPI and Lund-Malmö formulae are equally effective at predicting major adverse events in patients with PVD.

The impact of endovascular lower-limb revascularisation on the aortic augmentation index in patients with peripheral arterial disease

OBJECTIVES

The aortic augmentation index (AIx), a marker of arterial stiffness, and peripheral arterial disease (PAD) are associated with an increased cardiovascular risk. In claudicants, the effect of balloon angioplasty (percutaneous transluminal angioplasty, PTA) on AIx has not been determined so far.

METHODS

Measurements of the ankle-brachial pressure index (ABI) and AIx were performed before and 3 months after PTA and compared to age- and sex-matched PAD patients under best medical treatment.

RESULTS

The data of 61 patients (44% female, mean age 68 years) who underwent lower-limb PTA was compared to 48 conservatively treated patients (38% female, mean age 68 years). ABI significantly improved after PTA from 0.73 ± 0.02 to 0.85 ± 0.03 (p = 0.001), but remained unchanged in the control group (0.85 ± 0.23 and 0.80 ± 0.21; p = 0.16). Revascularisation was associated with a significant reduction of AIx from 31.5 ± 1.1% to 28.8 ± 1.1% after 3 months (p = 0.01). In the conservatively treated group, AIx did not change during follow-up (29.9 ± 1.1% to 29.9 ± 1.1%; p = 0.83).

CONCLUSION

Lower-limb revascularisation in PAD Rutherford stage II-III is associated with an improvement of markers for arterial stiffness.