Distribution of the ankle-brachial index and associated cardiovascular risk factors in a population of middle-aged and elderly koreans

Comparison of carotid plaque burden among healthy middle-aged men living in the US, Japan, and South Korea

BACKGROUND

Carotid plaque has emerged as a marker of coronary heart disease (CHD) risk. Comparison of carotid plaque burden between different race/ethnic groups may provide a relative estimate of their future CHD risk.

METHODS

We conducted a population-based study among apparently healthy middle-aged men aged 40-49 years (ERA JUMP study (n = 924)) and recruited 310 Whites in Pittsburgh, US, 313 Japanese in Otsu, Japan, and 301 Koreans in Ansan, South Korea. The number of carotid plaque and CHD risk factors was assessed using a standardized protocol across all centers. The burden of carotid plaque was compared between race/ethnic groups after adjustment for age and BMI, and after multivariable adjustment for other CHD risk factors using marginalized zero-inflated Poisson regression models. Cross-sectional associations of risk factors with plaque were examined.

RESULTS

Whites (22.8%) had more than four-fold higher prevalence (p < 0.01) of carotid plaque than Japanese men (4.8%) while the prevalence among Koreans was 10.6%. These differences remained significant after adjustment for age, BMI as well as other risk factors - incidence density ratio (95% confidence interval) for plaque was 0.13 (0.07, 0.24) for Japanese and 0.32 (0.18, 0.58) for Koreans as compared to Whites. Age, hypertension and diabetes were the only risk factors significantly associated with presence of carotid plaque in the overall population.

CONCLUSION

Whites have significantly higher carotid plaque burden than men in Japan and Korea. Lower carotid plaque burden among Japanese and Koreans is independent of traditional CVD risk factors.

Effects of folic acid supplementation on serum homocysteine levels, lipid profiles, and vascular parameters in post-menopausal Korean women with type 2 diabetes mellitus

BACKGROUND/OBJECTIVES

Complications of diabetes, such as cardiovascular disease, are associated with increased mortality among type 2 diabetes mellitus patients. Homocysteine has been recently identified as a predictor of cardiovascular disease-related complications in diabetes. We investigated whether or not supplementation with folic acid tablets can lower homocysteine levels and improve parameters related with vascular complications.

SUBJECTS/METHODS

We conducted a non-randomized 8-week trial involving postmenopausal diabetic women (n = 25) supplemented with 800 µg of folic acid (400 µg twice a day) daily. Subjects' serum levels of folate, homocysteine, and vitamin B₁₂ were measured, along with vascular function and brachial-ankle pulse wave velocity.

RESULTS

Folic acid supplementation significantly increased serum folate levels (P < 0.0001), reduced homocysteine levels (P < 0.0001), and increased vitamin B₁₂ levels (P = 0.0063). There were significant decreases in low-density lipoprotein cholesterol levels as well as the ratios of low-density lipoprotein cholesterol to high-density lipoprotein cholesterol and total cholesterol to high-density lipoprotein cholesterol. Brachial-ankle pulse wave velocities were not altered by supplementation. Changes in serum vitamin B₁₂ after folic acid supplementation were negatively correlated with changes in brachial-ankle pulse wave velocity.

CONCLUSIONS

In this study on postmenopausal Korean women with type 2 diabetes mellitus, folic acid supplementation reduced serum homocysteine levels, increased serum folate and vitamin B₁₂ levels, and lowered lipid parameters.

Flow Mediated Dilatation, Carotid Intima Media Thickness, Ankle Brachial Pressure Index and Pulse Pressure in Young Male Post Myocardial Infarction Patients in India

INTRODUCTION

Due to increase in Coronary Artery Disease (CAD) at a younger age, we should try to diagnose atherosclerotic process and population at risk, at the earliest. Flow Mediated Dilatation (FMD), Carotid Intima-Media Thickness (CIMT) and Ankle-Brachial Pressure Index (ABI) are probable markers for early atherosclerosis and may be useful in coronary risk stratification.

AIM

To compare and correlate the FMD, CIMT, ABI and Pulse Pressure (PP) in young male patients of Myocardial Infarction (MI) with age and sex matched healthy controls.

MATERIALS AND METHODS

Eighty male patients of MI aged ≤45 years, who presented to the Cardiac Care Unit and Department of Medicine of Guru Teg Bahadur Hospital, Delhi, India, from November 2010 to April 2012 were recruited consecutively for this case control study and same number of age and sex matched healthy controls were also analyzed. Six weeks after MI, FMD of the brachial artery, intima media thickness of carotid artery, ABPI and PP were measured in the cases and compared with healthy controls.

RESULTS

The FMD was lower among young patients of MI than controls (p<0.001). CIMT was higher among cases than controls (p=0.001). ABI was lower among cases than controls (p<0.001). Compared to controls, PP was higher among cases (p=0.001). In all subjects, a negative correlation between FMD and CIMT (r=-0.220, p=0.005) and a positive correlation between FMD and ABPI (r=0.304, p<0.001) was found. A statistically significant negative correlation was found between endothelial dependent FMD and PP among cases and control groups (r=-0.209, p=0.007).

CONCLUSION

Biophysical parameters were deranged in young post MI patients. Majority of our young male patients fell in low risk Framingham risk score but still they manifested with CAD. Despite six weeks of treatment among young male patients of MI, various biophysical parameters were still deranged.

Significant interarm blood pressure difference predicts cardiovascular risk in hypertensive patients: CoCoNet study

There has been a rising interest in interarm blood pressure difference (IAD), due to its relationship with peripheral arterial disease and its possible relationship with cardiovascular disease. This study aimed to characterize hypertensive patients with a significant IAD in relation to cardiovascular risk. A total of 3699 patients (mean age, 61 ± 11 years) were prospectively enrolled in the study. Blood pressure (BP) was measured simultaneously in both arms 3 times using an automated cuff-oscillometric device. IAD was defined as the absolute difference in averaged BPs between the left and right arm, and an IAD ≥ 10 mm Hg was considered to be significant. The Framingham risk score was used to calculate the 10-year cardiovascular risk. The mean systolic IAD (sIAD) was 4.3 ± 4.1 mm Hg, and 285 (7.7%) patients showed significant sIAD. Patients with significant sIAD showed larger body mass index (P < 0.001), greater systolic BP (P = 0.050), more coronary artery disease (relative risk = 1.356, P = 0.034), and more cerebrovascular disease (relative risk = 1.521, P = 0.072). The mean 10-year cardiovascular risk was 9.3 ± 7.7%. By multiple regression, sIAD was significantly but weakly correlated with the 10-year cardiovascular risk (β = 0.135, P = 0.008). Patients with significant sIAD showed a higher prevalence of coronary artery disease, as well as an increase in 10-year cardiovascular risk. Therefore, accurate measurements of sIAD may serve as a simple and cost-effective tool for predicting cardiovascular risk in clinical settings.

High Ankle-Brachial Index Indicates Cardiovascular and Peripheral Arterial Disease in Patients With Type 2 Diabetes

We assessed the association between high ankle-brachial index (ABI) and cardiovascular disease (CVD) and peripheral arterial disease (PAD) in Chinese patients with type 2 diabetes mellitus (T2DM). The ABI was measured, and foot inspection was performed in 2080 outpatients with T2DM. The clinical characters in different ABI levels were analyzed, and the diagnostic value of high ABI to CVD and PAD was determined. Compared with the normal ABI group, the high ABI (>1.3) group had a higher prevalence of CVD and PAD but less than the low ABI (≤0.9) group. High ABI was an independent risk factor for the development of CVD and PAD. Receiver-operating characteristic curve analysis showed that the optimal cutoff of high ABI to predict CVD and PAD was 1.43 and 1.45, respectively. The odds ratio of high ABI for CVD and PAD was 2.25 and 6.97, respectively, after adjusting for other confounding risk factors. In conclusion, high ABI indicated the risk of CVD and PAD in Chinese populations with T2DM.

Impact of weight loss on ankle-brachial index and interartery blood pressures

OBJECTIVE

To assess whether weight loss improves markers of peripheral artery disease and vascular stenosis.

METHODS

The Action for Health in Diabetes randomized clinical trial compared intensive lifestyle intervention (ILI) for weight loss to a control condition of diabetes support and education (DSE) in overweight or obese adults with type 2 diabetes. Annual ankle and brachial blood pressures over four years were used to compute ankle-brachial indices (ABIs) and to assess interartery blood pressure differences in 5018 participants.

RESULTS

ILI, compared to DSE, produced 7.8% (Year 1) to 3.6% (Year 4) greater weight losses. These did not affect prevalence of low (<0.90) ABI (3.60% in DSE versus 3.14% in ILI; P = 0.20) or elevated (>1.40) ABI (7.52% in DSE versus 7.59% in ILI: P = 0.90), but produced smaller mean (SE) maximum interartery systolic blood pressure differences among ankle sites [19.7 (0.2) mmHg for ILI versus 20.6 (0.2) mmHg for DSE (P < 0.001)] and between arms [5.8 (0.1) mmHg for ILI versus 6.1 (0.1) mmHg for DSE (P = 0.01)].

CONCLUSIONS

Four years of intensive behavioral weight loss intervention did not significantly alter prevalence of abnormal ABI, however, it did reduce differences in systolic blood pressures among arterial sites.

Comparison of global estimates of prevalence and risk factors for peripheral artery disease in 2000 and 2010: a systematic review and analysis

BACKGROUND

Lower extremity peripheral artery disease is the third leading cause of atherosclerotic cardiovascular morbidity, following coronary artery disease and stroke. This study provides the first comparison of the prevalence of peripheral artery disease between high-income countries (HIC) and low-income or middle-income countries (LMIC), establishes the primary risk factors for peripheral artery disease in these settings, and estimates the number of people living with peripheral artery disease regionally and globally.

METHODS

We did a systematic review of the literature on the prevalence of peripheral artery disease in which we searched for community-based studies since 1997 that defined peripheral artery disease as an ankle brachial index (ABI) lower than or equal to 0·90. We used epidemiological modelling to define age-specific and sex-specific prevalence rates in HIC and in LMIC and combined them with UN population numbers for 2000 and 2010 to estimate the global prevalence of peripheral artery disease. Within a subset of studies, we did meta-analyses of odds ratios (ORs) associated with 15 putative risk factors for peripheral artery disease to estimate their effect size in HIC and LMIC. We then used the risk factors to predict peripheral artery disease numbers in eight WHO regions (three HIC and five LMIC).

FINDINGS

34 studies satisfied the inclusion criteria, 22 from HIC and 12 from LMIC, including 112,027 participants, of which 9347 had peripheral artery disease. Sex-specific prevalence rates increased with age and were broadly similar in HIC and LMIC and in men and women. The prevalence in HIC at age 45-49 years was 5·28% (95% CI 3·38-8·17%) in women and 5·41% (3·41-8·49%) in men, and at age 85-89 years, it was 18·38% (11·16-28·76%) in women and 18·83% (12·03-28·25%) in men. Prevalence in men was lower in LMIC than in HIC (2·89% [2·04-4·07%] at 45-49 years and 14·94% [9·58-22·56%] at 85-89 years). In LMIC, rates were higher in women than in men, especially at younger ages (6·31% [4·86-8·15%] of women aged 45-49 years). Smoking was an important risk factor in both HIC and LMIC, with meta-OR for current smoking of 2·72 (95% CI 2·39-3·09) in HIC and 1·42 (1·25-1·62) in LMIC, followed by diabetes (1·88 [1·66-2·14] vs 1·47 [1·29-1·68]), hypertension (1·55 [1·42-1·71] vs 1·36 [1·24-1·50]), and hypercholesterolaemia (1·19 [1·07-1·33] vs 1·14 [1·03-1·25]). Globally, 202 million people were living with peripheral artery disease in 2010, 69·7% of them in LMIC, including 54·8 million in southeast Asia and 45·9 million in the western Pacific Region. During the preceding decade the number of individuals with peripheral artery disease increased by 28·7% in LMIC and 13·1% in HIC.

INTERPRETATION

In the 21st century, peripheral artery disease has become a global problem. Governments, non-governmental organisations, and the private sector in LMIC need to address the social and economic consequences, and assess the best strategies for optimum treatment and prevention of this disease.

FUNDING

Peripheral Arterial Disease Research Coalition (Europe).

Prevalence of Asymptomatic Peripheral Arterial Disease and Related Risk Factors in Younger and Elderly Patients in Taiwan

We determined the prevalence of asymptomatic peripheral arterial disease (PAD) and cardiovascular risk factors in Taiwan. Ambulatory participants (n = 1915) without symptoms of PAD were enrolled (mean age of 61.2 years). The ankle-brachial index (ABI) was used to detect the PAD (ABI < 0.90). The overall prevalence of asymptomatic PAD was 5.4% (2.8% in the younger participants [<65 years of age, n = 1021] and 8.4% in the elderly participants [≥65 years of age, n = 894]). Younger participants with asymptomatic PAD had a significantly higher rate of hypertension (55.2% vs 30%) and obesity (31% vs 13.3%) than those without asymptomatic PAD ( P < .05). Elderly participants with asymptomatic PAD had a significantly higher rate of diabetes mellitus (36% vs 21.2%) and hypertension (69.3% vs 55.4%) than those without asymptomatic PAD ( P < .05). Asymptomatic PAD is prevalent among elderly Taiwanese individuals. Overall, age was the strongest risk factor for the development of asymptomatic PAD.

Cohort Profile: The Namwon Study and the Dong-gu Study

These two cohorts were designed to examine the increasing burden of chronic diseases among Korean populations. The studies investigated determinants for stroke, osteoporosis, dementia and cancer among middle-aged and elderly Korean populations. The Namwon Study baseline survey was performed between 2004 and 2007 (n = 10 667), and followed up 4 years later (n = 8157, follow-up rate = 76.5%). The baseline survey of the Dong-gu Study was administered over 2007-2010 (n = 9260), and will be followed up between 2014 and 2015. Questionnaires included assessment of cognitive function, psychiatric health and lifestyle factors. Clinical examinations, biochemical tests and genotyping focused on evaluating the determinants of target diseases and their intermediate phenotypes. Potential collaborators will be invited to contact the chief investigators.

Cilostazol for primary prevention of stroke in peripheral artery disease: a population-based longitudinal study in Taiwan

BACKGROUND

Clopidogrel, cilostazol, and aspirin were compared in terms of efficacy and safety for primary prevention of stroke in peripheral artery disease (PAD) patients.

METHODS

This retrospective cohort study analyzed data contained in the Taiwan National Health Insurance Bureau database for patients treated for PAD but not for stroke during 2002-2008. Patients were stratified according to treatment with aspirin, clopidogrel, cilostazol, or combined therapy. The primary efficacy and safety endpoints were stroke and hemorrhage.

RESULTS

Of the 931 patients enrolled in this study, 479 had received aspirin, 39 had received clopidogrel, 294 had received cilostazol alone, and 33 had received a cilostazol-based combined therapy. Compared to patients treated with aspirin, the patients treated with cilostazol had significantly lower all-stroke risk not only in the overall group (HR=0.66, 95% CI=0.48-0.90, p=0.0086), but also in the subgroup of patients with diabetes (HR=0.64, 95% CI=0.42-0.98, p=0.0394) and in the subgroup of patients with high cardiovascular risk (HR=0.66, 95% CI=0.46-0.95, p=0.0254). Additionally, compared to patients treated with aspirin, those treated with cilostazol did not have significantly more hemorrhagic events in the overall group, in the diabetes subgroup, or in the high cardiovascular risk subgroup. Clopidogrel, cilostazol-based combined therapy and aspirin did not significantly differ in terms of efficacy and hemorrhagic events.

CONCLUSION

Although this database study indicated that cilostazol therapy is an effective alternative treatment for primary prevention of stroke in PAD, further confirmation is needed in large, prospective, and randomized trials.

Cardiovascular Risk Factors and Distributions of the Ankle-Brachial Index among Type 2 Diabetes Mellitus Patients

Background. The aim of present study is to observe the association between the levels of ankle-brachial index (ABI) and cardiovascular risk factors among people with type 2 diabetes mellitus in north India. A cross-sectional study was carried out at a centre for heart and diabetic clinic in the state of Punjab on 1121 subjects (671 males and 450 females) with type 2 diabetes mellitus. History of symptoms related to cardiovascular diseases was noted, and blood pressure and anthropometric measurements were recorded. Ankle-brachial index (ABI) was measured using ultrasonic Doppler flow detector. Subjects with ABI ≤0.9 and ≥1.30 were classified as having low and high ABI, respectively. Females had a higher BMI and brachial-ankle pulse wave velocity (P < 0.001). Whereas, males had higher diastolic blood pressure and duration of type 2 diabetes mellitus. The differences of systolic blood pressure and ankle-brachial index were not found significant between the sexes. The prevalence of low ABI (<0.9) was 4.47% in men and 4.67% in women and high ABI (≥1.30) was prevalent in 14% of men and 10.45% of women. Age, BMI, baPWV, and blood pressures were significantly associated with ABI value in both sexes. The results suggested that the ABI might be used as a strong indicator for cardiovascular risk factors in type 2 diabetic subjects.

High prevalence of peripheral arterial disease in Korean patients with coronary or cerebrovascular disease

This prospective study surveyed the prevalence of peripheral arterial disease (PAD) in Korean patients with coronary arterial disease (CAD) or cerebrovascular disorder (CVD). From March 2010, 576 hospitalized patients in cardiovascular or stroke center were enrolled as the study group. Ankle-brachial index (ABI) was measured and the cut-off point for diagnosing PAD was ≤ 0.9 at rest. A total of 424 hospitalized patients in the Department of Surgery and aged ≥ 50 yr was enrolled as the control group. The prevalence of PAD was significantly higher in the study group than the control group (7.6% vs 1.7%; P < 0.001). To analyze the relationship of other vascular diseases and PAD, the patients were regrouped; group A (no CAD or CVD), group B (CAD only), group C (CVD only), and group D (CAD and CVD). Compared with group A, those with other vascular diseases (group B, C, D) had significantly higher prevalence of PAD, diabetes, dyslipidemia, renal insufficiency and claudication. The trend that patients with CAD or CVD are at risk of PAD is observed in this cross-sectional study in Koreans. Routine ABI measurement is recommended in these high-risk groups for early detection and proper management of PAD.

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.

[Obliterating arterial disease of the legs in women]

The widespread use of the ankle-brachial index (ABI) enabled to reveal the high prevalence of lower extremities peripheral arterial disease (PAD) in women, even higher than in men in several series. Nonetheless, the use of a same ABI threshold for men and women may overestimate the prevalence of subclinical PAD in women. Conversely, the clinical manifestations of PAD are more often atypical in women, with as a result, a delayed diagnosis and management. The level of association between cardiovascular disease risk factors and PAD is similar in both genders. To date, there is no evidence for any association between PAD and different hormonal events in women. Despite an inverse association between hormonal replacement therapy (HRT) after menopause and PAD in epidemiological studies, the trials failed to evidence any protective effect of HRT to prevent PAD. Women with PAD are advised to discontinue HRT in case of limb revascularization. The long-term local and functional prognosis of PAD seems more severe in women, but this is partly explained by a delayed onset of the disease, occurring at a later age. Similarly, the general cardiovascular prognosis PAD is also poorer in women than in men.

Peripheral arterial disease and clinical risks in Taiwanese hemodialysis patients

Peripheral arterial disease (PAD) is associated with significant morbidity and mortality and is an important marker of systemic atherosclerosis. However, little is known about the associated risk factors for PAD in patients on maintenance hemodialysis (HD). We collected the basic data and possible risk factors associated with PAD for 277 patients on maintenance HD. Furthermore, we measured ankle-brachial blood pressure index (ABI) in these patients. PAD was defined as an ABI value less than 0.90. The prevalence of PAD in our HD center was 22.8% (61/268). Advanced age (P = 0.006), longer history of HD (P < 0.001), diabetes (P = 0.002) and presence of PAD symptoms (P < 0.001) were independent predictors of PAD. PAD patients with diabetes had shorter history of HD (P = 0.001). 2-vessel PAD had higher serum cholesterol in HD patients (>or= 200 vs < 200 mg/dL; Odds ratio, 12.12, 95% confidence interval, 2.199-67.79; P < 0.004).

Measurement characteristics of the ankle-brachial index: results from the Action for Health in Diabetes study

Many protocols have been used in clinical and research settings for collecting systolic blood pressure (SBP) measurements to calculate the ankle-brachial index (ABI); however, it is not known how useful it is to replicate measurements and which measures best reflect cardiovascular risk. Standardized measurements of ankle and arm SBP from 5140 overweight or obese individuals with type 2 diabetes were used to estimate sources of variation. Measurement characteristics of leg-specific ABI, as calculated using a standard algorithm based on the highest SBP of the dorsalis pedis or posterior tibial arteries, were projected using simulations. Coefficients of variability ranged from 2% to 3% when single SBP measurements were used and ABI was overestimated by 2-3%. Taking two SBP measurements at each site reduced standard errors and bias each by 30-40%. The sensitivity of detecting low ABI ranges exceeded 90% for ABI within 0.05 of the 0.90 clinical cut-point. The average and the minimum of the two (i.e. right and left) leg-specific ABI values had similar U-shaped relationships with Framingham risk scores; however, the average leg ABI had slightly greater precision. Replicating SBP measurements reduces the error and bias of ABI. Averaging leg-specific values may increase power for characterizing cardiovascular disease risk.

Peripheral Arterial Disease study (PERART): prevalence and predictive values of asymptomatic peripheral arterial occlusive disease related to cardiovascular morbidity and mortality

BACKGROUND

The early diagnosis of atherosclerotic disease is essential for developing preventive strategies in populations at high risk and acting when the disease is still asymptomatic. A low ankle-arm index (AAI) is a good marker of vascular events and may be diminished without presenting symptomatology (silent peripheral arterial disease). The aim of the PERART study (PERipheral ARTerial disease) is to determine the prevalence of peripheral arterial disease (both silent and symptomatic) in a general population of both sexes and determine its predictive value related to morbimortality (cohort study).

METHODS/DESIGN

This cross-over, cohort study consists of 2 phases: firstly a descriptive, transversal cross-over study to determine the prevalence of peripheral arterial disease, and secondly, a cohort study to evaluate the predictive value of AAI in relation to cardiovascular morbimortality. From September 2006 to June 2007, a total of 3,010 patients over the age of 50 years will be randomly selected from a population adscribed to 24 healthcare centres in the province of Barcelona (Spain). The diagnostic criteria of peripheral arterial disease will be considered as an AAI < 0.90, determined by portable Doppler (8 Mhz probe) measured twice by trained personnel. Cardiovascular risk will be calculated with the Framingham-Wilson tables, with Framingham calibrated by the REGICOR and SCORE groups. The subjects included will be evaluted every 6 months by telephone interview and the clnical history and death registries will be reviewed. The appearance of the following cardiovascular events will be considered as variables of response: transitory ischaemic accident, ictus, angina, myocardial infartction, symptomatic abdominal aneurysm and vascular mortality.

DISCUSSION

In this study we hope to determine the prevalence of peripheral arterial disease, especially the silent forms, in the general population and establish its relationship with cardiovascular morbimortality. A low AAI may be a better marker of arterial disease than the classical cardiovascular risk factors and may, therefore, contribute to improving the predictive value of the equations of cardiovascular risk and thereby allowing optimisation of multifactorial treatment of atherosclerotic disease.

Prevalence of and risk factors for peripheral arterial disease in the patients with hypertension among Han Chinese

OBJECTIVES

Peripheral arterial disease (PAD) is associated with morbidity and mortality of coronary heart disease and stroke. Hypertension is an independent risk factor for peripheral arterial disease. However, the prevalence and risk factors of PAD in hypertensive patients have not been studied in China.

METHODS

In order to investigate the prevalence of PAD and its risk factors in China, a cross-sectional study was carried out. A total of 4716 patients with hypertension and 833 age-gender matched people without hypertension were recruited; age 40 to 75 years, from seven rural communities. PAD was defined as an ankle-brachial index (ABI) <or= 0.9 in either leg; hypertension was defined as systolic blood pressure >or=140 mm Hg, diastolic blood pressure >or=90 mm Hg, or history of antihypertensive drug use.

RESULTS

The prevalence of PAD is 8.7% (n = 408) in patients with hypertension (n = 4716), higher than in people without hypertension (5.0%, n = 833, P = .004). Hypertensive patients with PAD were older, (61 +/- 8.6 vs 58 +/- 8.6, P < .01), had more conventional cardiovascular risk factors including systolic blood pressure (170 +/- 22.6 vs 167 +/- 22.7, P < .01), pulse pressure (72 +/- 19.7 vs 68 +/- 18.9, P < .01), blood glucose (5.8 +/- 2.2 vs 5.6 +/- 1.7, P < .05), total cholesterol (5.7 +/- 1.3 vs 5.5 +/- 1.1, P < .05), and serum uric acid (355 +/- 98.0 vs 293 +/- 86.2, P < .05) than the hypertensive patients without PAD. After adjusting for gender, age, and other cardiovascular risk factors by using multiple logistical regression analysis, PAD was still associated with current smoking (odds ratio [OR] = 1.65, 95% confidence interval [CI] 1.18-2.29), history of stroke (OR = 1.50, 95% CI 1.12-2.00), serum uric acid (OR = 1.21, 95% CI 1.10-1.59), and total cholesterol (OR = 1.12, 95% CI 1.10-1.59).

CONCLUSION

This study reports, for the first time, the prevalence of PAD in Chinese patients with hypertension, which is quite different from that in westerners, and that PAD is independently associated with conventional cardiovascular risk factors.

The Association between Ankle-Brachial Index and Cardiovascular or All-Cause Mortality in Metabolic Syndrome of Elderly Chinese

The ankle-brachial index (ABI) is a non-invasive, reliable measurement of lower-extremity ischemia. A low ABI is associated with increased risk of coronary heart disease, stroke and death. However, the relationship between ABI and all-cause mortality or cardiovascular disease (CVD) mortality in patients with metabolic syndrome (MetS) has not been well studied. Accordingly, we here investigated the association between ABI and all-cause and CVD mortality in an elderly Chinese population with MetS. A total of 2,274 MetS patients diagnosed under the criteria proposed by the International Diabetes Federation were divided into two groups based on repeated ABI measurement over a period of 13.6 months: ABI<or=0.9 (n=525) and ABI 0.91-1.4 (n=1,749). Each of the baseline characteristics of age, systolic blood pressure, diabetes mellitus morbidity, and smoking history were significantly different between the two groups (p<0.05 or p<0.01). All-cause mortality and CVD mortality decreased gradually as the ABI increased from 0.4 to 1.4. In Cox regression analysis, the relative ratio of all-cause mortality to CVD mortality also showed a tendency to decrease with increasing ABI. In elderly patients with MetS, ABI is one of the most important indexes for determining the possible prognosis and predicting all-cause and CVD mortality. People with relatively older age, higher systolic blood pressure, diabetes mellitus morbidity and smoking history may be at risk of lower ABI (<or=0.9) and higher all-cause and CVD mortality. Our results suggest the urgent need for repeated ABI measurement in clinical practice, both during individual visits and also over time, before diagnosing peripheral artery disease and making a therapeutic decision, especially in certain high-risk populations such as patients with MetS.