Abnormally low and high ankle-brachial indices are independently associated with increased left ventricular mass index in chronic kidney disease

Upstroke Time as a Novel Predictor of Mortality in Patients with Chronic Kidney Disease

Upstroke time (UT), measured from the foot-to-peak peripheral pulse wave, is a merged parameter used to assess arterial stiffness and target vascular injuries. In this study, we aimed to investigate UT for the prediction of cardiovascular and all-cause mortality in patients with chronic kidney disease (CKD). This longitudinal study enrolled 472 patients with CKD. Blood pressure, brachial pulse wave velocity (baPWV), and UT were automatically measured by a Colin VP-1000 instrument. During a median follow-up of 91 months, 73 cardiovascular and 183 all-cause mortality instances were recorded. Multivariable Cox analyses indicated that UT was significantly associated with cardiovascular mortality (hazard ratio (HR) = 1.010, p = 0.007) and all-cause mortality (HR = 1.009, p < 0.001). The addition of UT into the clinical models including traditional risk factors and baPWV further increased the value in predicting cardiovascular and all-cause mortality (both p < 0.001). In the Kaplan–Meier analyses, UT ≥ 180 ms could predict cardiovascular and all-cause mortality (both log-rank p < 0.001). Our study found that UT was a useful parameter in predicting cardiovascular and all-cause mortality in CKD patients. Additional consideration of the UT might provide an extra benefit in predicting cardiovascular and all-cause mortality beyond the traditional risk factors and baPWV.

Association of 4-limb systolic blood pressure heterogeneity with peripheral artery disease and left ventricular mass index

A large interarm and interleg systolic blood pressure (SBP) difference and ankle-brachial index (ABI) <0.9 were associated with peripheral artery disease and left ventricular hypertrophy. These 3 parameters were derived from 4-limb SBP data. However, there is no study to assess clinical significance of SBP heterogeneity in 4 limbs. The aim of this study was to evaluate the association of 4-limb SBP standard deviation (SD) with peripheral vascular parameters and echocardiographic data in patients with or without clinical findings of peripheral artery disease.A total of 1240 patients were included, of whom 1020 had no clinical evidence of overt peripheral artery disease. The 4-limb blood pressures, brachial-ankle pulse wave velocity, and ABI were measured simultaneously by an ABI-form device.In the multivariable linear regression analysis, increased left ventricular mass index (LVMI), ABI < 0.9, interarm SBP difference >10 mm Hg, and interleg SBP difference >15 mm Hg (P ≤ .030) were associated with increased 4-limb SBP SD. Additionally, a subgroup multivariable linear regression analysis in 1020 patients without ABI < 0.9, interarm SBP difference >10 mm Hg, and interleg SBP difference >15 mm Hg found 4-limb SBP SD still had a positive correlation with LVMI (P < .001).In addition to significant association with ABI < 0.9, interarm SBP difference >10 mm Hg, and interleg SBP difference >15 mm Hg, 4-limb SBP SD was positively correlated with LVMI in the multivariable linear regression analysis in all study patients. Furthermore, in the subgroup of patients without clinical evidence of peripheral artery disease, 4-limb SBP SD still had a positive correlation with LVMI. Hence, assessment of 4-limb SBP heterogeneity is useful in identification of high-risk group of peripheral artery disease and/or increased LVMI, irrespective of the presence of overt peripheral artery disease.

Ankle-Brachial Index is a Predictor of Future Incident Chronic Kidney Disease in a General Japanese Population

AIMS

The ankle-brachial index (ABI) can be a prognostic marker for chronic kidney disease (CKD) in Western populations. Since there is little relevant evidence for Asian populations, we investigated the relationship between ABI and the risk of incident CKD in a general Japanese population.

METHODS

The cohort included 5,072 participants aged 30-79 without a history of renal disease or cerebro-cardiovascular disease. Incident CKD, defined as an estimated glomerular filtration rate ＜60 (mL/min/1.73 m2) and/or proteinuria (≥ 1＋ on urine dipstick), was compared among participants grouped according to baseline ABI: 0.90-0.99, 1.00-1.09, 1.10-1.19, 1.20-1.29, and 1.30-1.39. Hazard ratios for incident CKD were estimated using a Cox proportional hazards model, with the ABI 1.10-1.19 group serving as the reference.

RESULTS

The CKD incidence rate (/100 person-years) was 1.80 during the mean follow-up period of 5.1 years. The CKD incidence rate was 3.04 in the ABI category 0.90-0.99, 1.58 in ABI 1.00-1.09, 1.72 in ABI 1.10-1.19, 2.01 in ABI 1.20-1.29, and 3.33 in ABI 1.30-1.39. The hazard ratios for developing CKD were 2.14 (95% confidence interval 1.16-3.92) in ABI 0.90-0.99, 1.08 (0.83-1.41) in ABI 1.00-1.09, 1.03 (0.83-1.29) in ABI 1.20-1.29, and 1.37 (0.77-2.47) in ABI 1.30-1.39, after adjusting for age, sex, systolic blood pressure, diabetes, and other confounding factors.

CONCLUSIONS

In a general Japanese population, an ABI of 0.90-0.99 was associated with an increased risk of incident CKD, independent of traditional cardiovascular risk factors.

Comparison of ankle-brachial index and upstroke time in association with target organ damage: the Northern Shanghai Study

A recent study indicated that upstroke time per cardiac cycle (UTCC) in lower extremities is equivalent to ankle-brachial index (ABI) in diagnosing peripheral arterial disease and in predicting cardiovascular mortality. In this study, we aimed to compare ABI and UTCC in relation to target organ damage. A cohort of 1841 elderly participants from the Northern Shanghai Study was studied. ABI and UTCC were measured using VP-1000 device. Target organ damage including left ventricular hypertrophy and diastolic dysfunction, carotid intima-media thickness and plaque, carotid-femoral pulse wave velocity (CF-PWV), and renal damage, were evaluated by standardized methods. In correlation analysis, ABI and UTCC both significantly correlated with CF-PWV, carotid plaque, and estimated glomerular filtration rate, but not with cardiac damage. Compared with ABI, UTCC showed stronger correlation with CF-PWV. When ABI and UTCC separately put into fully adjusted multivariate logistic regression models, both ABI (OR: 2.27; 95% CI: 1.63-3.17) and UTCC (OR: 1.63; 95% CI: 1.18-2.24) significantly associated with carotid plaque, but only UTCC significantly associated with increased CF-PWV (OR: 1.66; 95% CI: 1.15-2.42) and renal damage (OR: 1.63; 95% CI: 1.07-2.47). When ABI and UTCC both put into multivariate stepwise logistic regression models together with covariates, consistent results were observed. In ROC curve analysis, after adjusted for cofounding factors, UTCC showed slightly greater area under curve than ABI in detecting increased CF-PWV (area under curve: 0.79 vs. 0.78; P = .008); however, no difference was observed between UTCC and ABI in discriminating renal damage and carotid plaque. In conclusion, compared with ABI, UTCC showed significantly stronger association with vascular and renal damage in this elderly Chinese cohort.

Association of Ankle-Brachial Index and Aortic Arch Calcification with Overall and Cardiovascular Mortality in Hemodialysis

Peripheral artery occlusive disease and vascular calcification are highly prevalent in hemodialysis (HD) patients, however the association of the combination of ankle-brachial index (ABI) and aortic arch calcification (AoAC) with clinical outcomes in patients undergoing HD is unknown. In this study, we investigated whether the combination of ABI and AoAC is independently associated with overall and cardiovascular mortality in HD patients. The median follow-up period was 5.7 years. Calcification of the aortic arch was assessed by chest X-ray. Forty-seven patients died including 24 due to cardiovascular causes during the follow-up period. The study patients were stratified into four groups according to an ABI < 0.95 or ≥0.95 and an AoAC score of >4 or ≤4 according to receiver operating characteristic curve. Those with an ABI < 0.95 and AoAC > 4 (vs. ABI ≥ 0.95 and AoAC score ≤ 4) were associated with overall (hazard ratio [HR], 4.913; 95% confidence interval [CI], 1.932 to 12.497; p = 0.001) and cardiovascular (HR, 3.531; 95% CI, 1.070 to 11.652; p = 0.038) mortality in multivariable analysis. The combination of a low ABI and increased AoAC was associated with increased overall and cardiovascular mortality in patients undergoing HD.

Association of interankle systolic blood pressure difference with peripheral vascular disease and left ventricular mass index

BACKGROUND

An interankle systolic blood pressure (SBP) difference has been associated with overall and cardiovascular mortality. We investigated whether an association existed between this difference and ankle-brachial index (ABI), brachial-ankle pulse wave velocity (baPWV), and echocardiographic parameters.

METHODS

A total of 1,059 patients referred for echocardiographic examination were included in the study. The 4 limb blood pressures were measured simultaneously using an ABI-form device.

RESULTS

We performed multivariate forward analysis to determine the factors associated with an interankle SBP difference ≥ 15mm Hg. An ABI < 0.9 (P < 0.001), high baPWV (P < 0.001), and increased left ventricular mass index (LVMI; P = 0.004) were associated with an interankle SBP difference ≥ 15mm Hg. Also, the addition of an interankle SBP difference ≥ 15mm Hg to a model of clinical features could significantly improve the value in predicting ABI < 0.9 (P < 0.001) and increased LVMI (P = 0.036).

CONCLUSIONS

Our study demonstrated that ABI < 0.9, high baPWV, and increased LVMI were independently associated with an interankle SBP difference ≥ 15mm Hg. Also, an interankle SBP difference ≥ 15mm Hg could offer an extra benefit in identifying patients with ABI < 0.9 and increased LVMI beyond conventional clinical features. Hence, calculation of interankle SBP difference may provide additional information for identifying patients with peripheral vascular disease and increased LVMI.

Association of chronic kidney disease and peripheral artery disease with inappropriate left ventricular mass

Inappropriate left ventricular mass index (LVM) may develop as a response to particular hemodynamic and metabolic alterations. Inappropriate LVM and peripheral artery disease (PAD) characterized by abnormally low or high ankle-brachial index (ABI) are common in chronic kidney disease (CKD) patients, in whom there may be a close and cause-effect relationship. The aim of this study is to assess whether CKD and abnormal ABI has an independent and additive association with inappropriate LVM. A total of 1110 patients were included in the study. Inappropriate LVM was defined as observed LVM more than 28% of the predicted value. The ABI was measured using an ABI-form device. PAD was defined as ABI <0.9 or >1.3 in either leg. Multivariate analysis showed that patients with estimated glomerular filtration rate (eGFR) <45 ml/min/1.73 m² (odds ratio [OR], 1.644; P = 0.011) and PAD (OR, 2.082; P = 0.002) were independently associated with inappropriate LVM. The interaction between eGFR <45 ml/min/1.73 m² and PAD on inappropriate LVM was statistically significant (P = 0.044). Besides, eGFR<45 ml/min/1.73 m² (change in observed/predicted LVM, 19.949; P<0.001) and PAD (change in observed/predicted LVM, 11.818; P = 0.003) were also significantly associated with observed/predicted LVM. Our findings show that eGFR <45 ml/min/1.73 m² and PAD are independently and additively associated with inappropriate LVM and observed/predicted LVM. Assessments of eGFR and ABI may be useful in identifying patients with inappropriate LVM.