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Michael H Criqui

Publications and source records attributed to Michael H Criqui.

At least 19 recordsLinked to original sources
PubMed2006

Lower extremity nerve function in patients with lower extremity ischemia.

BACKGROUND: We determined whether lower extremity ischemia, as measured by the ankle brachial index (ABI), is associated with impaired lower extremity nerve function. METHODS: Participants included 478 persons with peripheral arterial disease (PAD) identified from noninvasive vascular laboratories and 292 persons without PAD identified from a general medicine practice and noninvasive vascular laboratories. Peripheral arterial disease was defined as an ABI lower than 0.90 (mild PAD: ABI, 0.70 to <0.90; moderate PAD: ABI, 0.50 to <0.70; and severe PAD: ABI, <0.50). The ABI and electrophysiologic measures of the peroneal, sural, and ulnar nerves were obtained. RESULTS: Among 546 participants without diabetes, PAD participants had significantly impaired peripheral nerve function in the upper and lower extremities compared with non-PAD participants. After adjusting for age, sex, race, smoking, height, body mass index, recruitment source, alcohol use, disk disease, spinal stenosis, cardiac disease, and cerebrovascular disease, these associations were not statistically significant. After adjusting for confounders among nondiabetic participants, those with severe PAD (ABI, <0.50) had poorer peroneal nerve conduction velocity (NCV) compared with participants without PAD (42.6 vs 44.8 m/s; P = .003) and poorer peroneal NCV compared with participants with mild PAD (42.6 vs 45.0 m/s; P = .001) or moderate PAD (42.6 vs 44.1 m/s; P = .03). Among 224 participants with diabetes, after adjusting for confounders, PAD was associated with poorer peroneal NCV (40.8 vs 43.5 m/s; P = .01), sural nerve amplitude (3.1 vs 4.8 muV; P = .045), and ulnar NCV (47.6 vs 50.2 m/s; P = .03) compared with those without PAD. CONCLUSIONS: Our findings suggest that leg ischemia impairs peroneal nerve function. This association is less strong in patients with diabetes, perhaps because of the overriding influence of diabetes on peripheral nerve function. Clinicians should consider screening for PAD in patients with idiopathic peroneal nerve dysfunction. Peripheral arterial disease-associated nerve dysfunction may contribute to PAD-associated functional impairment.

Aged↗
PubMed2006

The effect of novel cardiovascular risk factors on the ethnic-specific odds for peripheral arterial disease in the Multi-Ethnic Study of Atherosclerosis (MESA).

OBJECTIVES: The purpose of this study was to: 1) determine the significance and magnitude of associations between novel cardiovascular disease (CVD) risk factors and peripheral arterial disease (PAD) after adjustment for traditional risk factors; and 2) ascertain the extent to which novel risk factors explain the excess or lower risk for PAD in different ethnic groups. BACKGROUND: Previous reports have found a significant difference in the risk of PAD by ethnic group, with some of the risk difference attributed to different levels of traditional CVD risk factors. METHODS: A total of 6,814 individuals free of clinically apparent CVD were enrolled in the MESA (Multiethnic Study of Atherosclerosis) and underwent standardized testing for the presence of PAD by the ankle-brachial index. These subjects also had fasting blood drawn for serum cholesterol, glucose, and a number of novel biomarkers for CVD. Non-Hispanic whites were the largest ethnic group (38%), followed by African Americans (28%), Hispanics (22%), and Chinese (12%). RESULTS: In this cross-sectional analysis, 6,653 subjects with an ankle brachial index <1.40 were analyzed. The mean (SD) age was 62.2 (10.2) years, and 52.9% were women. Interleukin-6, fibrinogen, D-dimer, and homocysteine were significantly associated with PAD after adjustment for traditional CVD risk factors. Compared with non-Hispanic whites and after adjustment for traditional and "novel" risk factors, the odds for PAD were 1.47 (95% confidence interval [CI]: 1.07 to 2.02) times higher in African Americans, while being 0.45 (95% CI: 0.29 to 0.70) and 0.44 (95% CI: 0.24 to 0.78) in Hispanics and Chinese, respectively. CONCLUSIONS: Ethnic associations with PAD remained significant even after adjustment for traditional and novel risk factors. This suggests that unknown factors may account for the residual ethnic differences in PAD.

Black or African American↗
PubMed2006

Physical activity during daily life and mortality in patients with peripheral arterial disease.

BACKGROUND: We determined whether patients with lower-extremity peripheral arterial disease (PAD) who are more physically active during daily life have lower mortality rates than PAD patients who are less active. METHODS AND RESULTS: Participants were 460 men and women with PAD (mean age 71.9+/-8.4 years) followed up for 57 months (interquartile range 36.6 to 61.9 months). At baseline, participants were interviewed about their physical activity. Vertical accelerometers measured physical activity continuously over 7 days in 225 participants. Analyses were adjusted for age, sex, race, body mass index, hypertension, smoking, comorbidities, total cholesterol, HDL cholesterol, leg symptoms, and ankle-brachial index. At 57-month follow-up, 134 participants (29%) had died, including 75 participants (33%) who wore accelerometers. Higher baseline physical activity levels measured by vertical accelerometer were associated with lower all-cause mortality (P(trend)=0.003). Relative to PAD participants in the highest quartile of accelerometer-measured physical activity, those in the lowest quartile had higher total mortality (hazard ratio 3.48, 95% confidence interval 1.23 to 9.87, P=0.019). Similar results were observed for the combined outcome of cardiovascular events or cardiovascular mortality (P(trend)=0.005). Higher numbers of stair flights climbed during 1 week were associated with lower total mortality (P(trend)=0.035). CONCLUSIONS: PAD patients with higher physical activity during daily life have reduced mortality and cardiovascular events compared with PAD patients with the lowest physical activity, independent of confounders. Further study is needed to determine whether interventions that increase physical activity during daily life are associated with improved survival in patients with PAD.

Activities of Daily Living↗
PubMed2006

Risk factors for progression of peripheral arterial disease in large and small vessels.

BACKGROUND: Data on the natural history of peripheral arterial disease (PAD) are scarce and are focused primarily on clinical symptoms. Using noninvasive tests, we assessed the role of traditional and novel risk factors on PAD progression. We hypothesized that the risk factors for large-vessel PAD (LV-PAD) progression might differ from small-vessel PAD (SV-PAD). METHODS AND RESULTS: Between 1990 and 1994, patients seen during the prior 10 years in our vascular laboratories were invited for a new vascular examination. The first assessment provided baseline data, with follow-up data obtained at this study. The highest decile of decline was considered major progression, which was a -0.30 ankle brachial index decrease for LV-PAD and a -0.27 toe brachial index decrease for SV-PAD progression. In addition to traditional risk factors, the roles of high-sensitivity C-reactive protein, serum amyloid-A, lipoprotein(a), and homocysteine were assessed. Over the average follow-up interval of 4.6+/-2.5 years, the 403 patients showed a significant ankle brachial index and toe brachial index deterioration. In multivariable analysis, current smoking, ratio of total to HDL cholesterol, lipoprotein(a), and high-sensitivity C-reactive protein were related to LV-PAD progression, whereas only diabetes was associated with SV-PAD progression. CONCLUSIONS: Risk factors contribute differentially to the progression of LV-PAD and SV-PAD. Cigarette smoking, lipids, and inflammation contribute to LV-PAD progression, whereas diabetes was the only significant predictor of SV-PAD progression.

Aged↗
PubMed2006

Effects of conjugated equine estrogen on stroke in the Women's Health Initiative.

BACKGROUND: The Women's Health Initiative (WHI) Estrogen Alone trial assessed the balance of benefits and risks of hormone use in healthy postmenopausal women. The trial was stopped prematurely because there was no benefit for coronary heart disease and an increased risk of stroke. This report provides a thorough analysis of the stroke finding using the final results from the completed trial database. METHODS AND RESULTS: The WHI Estrogen Alone hormone trial is a multicenter, double-blind, placebo-controlled, randomized clinical trial in 10,739 women aged 50 to 79 years who were given daily conjugated equine estrogen (CEE; 0.625 mg; n=5310) or placebo (n=5429). During an average follow-up of 7.1 years, there were 168 strokes in the CEE group and 127 in the placebo group; 80.3% of strokes were ischemic. For all stroke the intention-to-treat hazard ratio [HR] (95% CI) for CEE versus placebo was 1.37 (1.09 to 1.73). The HR (95% CI) was 1.55 (1.19 to 2.01) for ischemic stroke and 0.64 (0.35, 1.18) for hemorrhagic stroke. The HRs indicate excess risk of ischemic stroke was apparent in all categories of baseline stroke risk, including younger and more recently menopausal women and in women with prior or current use of statins or aspirin. CONCLUSIONS: CEE increases the risk of ischemic stroke in generally healthy postmenopausal women. The excess risk appeared to be present in all subgroups of women examined, including younger and more recently menopausal women. There was no convincing evidence to suggest that CEE had an effect on the risk of hemorrhagic stroke.

Aged↗
PubMed2006

Can we improve cardiovascular risk prediction beyond risk equations in the physician's office?

BACKGROUND AND OBJECTIVES: Beyond a global estimation of the cardiovascular risk through the assessment of major risk factors and their integration in dedicated risk scales or equations, the use of specific markers provides additive prognostic information at an individual level, including predisposing factors, which are not included in the risk equations as well as the individual susceptibility to their long-term exposure. However, the majority of these markers require specific devices and skills, which are not widely available in primary care. METHODS: Some clinical and/or "low-cost" parameters are shown to be valuable risk markers, and their use could refine the risk estimation in a physician's office. Several epidemiologic studies suggest the heart rate, the pulse pressure and the ankle-brachial index are effective cardiovascular risk markers. The arms systolic pressure asymmetry could also be a useful marker of risk. RESULTS AND CONCLUSIONS: Through a general review, the authors evaluate the potential of these clinical markers, including their use in combination for more accurate risk determination.

Ankle↗
PubMed2006

Statin use and functional decline in patients with and without peripheral arterial disease.

OBJECTIVES: We determined whether statin use (vs. non-use) is associated with less annual decline in lower-extremity functioning in patients with and without lower-extremity peripheral arterial disease (PAD) over three-year follow-up. BACKGROUND: It is unclear whether statin use is associated with less functional decline in patients with PAD. METHODS: Participants included 332 men and women with an ankle brachial index (ABI) <0.90 and 212 with ABI 0.90 to 1.50. Functional outcomes included 6-min walk distance and usual and rapid-pace 4-m walking velocity. A summary performance score combined performance in walking speed, standing balance, and time for five repeated chair rises into an ordinal score ranging from 0 to 12 (12 = best). RESULTS: Adjusting for age, race, gender, comorbidities, education, health insurance, total cholesterol/high-density lipoprotein level, body mass index, pack-years of smoking, leg symptoms, immediately previous year functioning, statin use/non-use, ABI, and change in ABI, the PAD participants using statins had less annual decline in usual-pace walking velocity (0.002 vs. -0.024 m/s/year, p = 0.013), rapid-pace walking velocity (-0.006 vs. -0.042 m/s/year, p = 0.006), 6-min walk performance (-34.5 vs. -57.9 feet/year, p = 0.088), and the summary performance score (-0.152 vs. -0.376, p = 0.067) compared with non-users. These associations were attenuated slightly by additional adjustment for high-sensitivity C-reactive protein levels. Among non-PAD participants, there were no significant associations between statin use and functional decline. CONCLUSIONS: The PAD patients on statins have less annual decline in lower-extremity performance than PAD patients who are not taking statins.

Aged↗
PubMed2006

Mitral and aortic annular calcification are highly associated with systemic calcified atherosclerosis.

BACKGROUND: Atherosclerosis has been implicated as a cause of valvular calcification. The aim of this study was to determine whether atherosclerotic calcification in multiple vascular areas is significantly associated with aortic or mitral annular calcification independent of traditional risk factors. METHODS AND RESULTS: A total of 1242 consecutive asymptomatic patients free of clinical coronary heart disease were studied by electron-beam computed tomography for the extent of calcium due to atherosclerosis in 5 distinct vascular beds and calcium in the aortic and mitral annuli. Nearly 24% had calcium in the aortic annulus, whereas 8% were found to have mitral annular calcification. Age and a history of hypertension were the only traditional cardiovascular risk factors that were independently associated with prevalent calcification in the aortic and mitral annuli. After adjustment for age, gender, and cardiovascular disease risk factors, subjects with calcium in the thoracic aorta had the highest odds for the presence of aortic annular calcium (OR=3.9, P<0.01), whereas those with calcium in the abdominal aorta had the highest odds for mitral annular calcification (OR=5.1, P=0.01). Standardized increases in calcium in the abdominal aorta (OR=2.0, P<0.01) and iliacs (OR=1.8, P=0.01) were significantly associated with calcium in the aortic annulus after adjustment for the extent of calcium in the other vascular beds, whereas the thoracic aorta was significantly associated (OR=1.4, P=0.02) with calcium in the mitral annulus. CONCLUSIONS: This study supports the hypothesis that calcification of the mitral and aortic annuli is related to atherosclerosis in other vascular beds.

Adult↗
PubMed2006

Physical performance in peripheral arterial disease: a slower rate of decline in patients who walk more.

BACKGROUND: Exercise rehabilitation programs increase treadmill walking performance in patients with peripheral arterial disease (PAD) and intermittent claudication. However, it is unknown whether patients with PAD who walk for exercise regularly have less functional decline than those with less walking activity. OBJECTIVE: To determine whether patients with PAD who report that they walk for exercise 3 or more times per week have less annual functional decline than those who walk for exercise less frequently. DESIGN: Prospective cohort study with a median follow-up of 36 months (interquartile range, 24 to 36 months). SETTING: Academic medical center. PARTICIPANTS: 417 men and women with PAD. MEASUREMENTS: Participants were classified at baseline and annually according to the number of times they reportedly walked for exercise each week. Functional assessments (6-minute walk distance, 4-meter walking speed, summary performance score) were measured at baseline and annually. Results were adjusted for age, sex, ethnicity, comorbid conditions, body mass index, ankle-brachial index, education, leg symptoms, cigarette use, geriatric depression score, previous year's level of functioning, and patterns of missing data. RESULTS: Compared with those who exercised less frequently, patients who walked for exercise 3 or more times per week had a significantly smaller average annual decline in 6-minute walking distance (-48.0 feet per year compared with -56.6 feet per year for those who walked 1 to 2 times per week and -79.4 feet per year for nonexercisers; P for trend = 0.037). Patients who walked for exercise at least 3 times per week experienced a smaller average annual decline in the usual-paced 4-meter walking velocity (-0.014 m/s per year compared with -0.022 m/s per year for those who walked 1 to 2 times per week and -0.045 m/s per year for nonexercisers; P = 0.005). Similar findings were observed for the fast-paced 4-meter walk. The subset of asymptomatic patients who walked for exercise 3 or more times per week had annual declines in 6-minute walking performance (P = 0.107), normal-paced walking velocity (P = 0.065), and the summary performance score (P = 0.115); however, these declines were smaller than those observed in asymptomatic participants who walked fewer than 3 times per week. LIMITATIONS: Because this was an observational study, associations reported here cannot be construed as causal relationships. Sample sizes for subgroup analyses were small, which limited statistical power. CONCLUSION: Among patients with PAD, self-directed walking exercise performed at least 3 times weekly is associated with significantly less functional decline during the subsequent year. Similar trends were observed in the subset of asymptomatic patients with PAD. These findings may be particularly important for the numerous patients with PAD who do not have access to supervised walking exercise programs.

Disability Evaluation↗
PubMed2006

Conjugated equine estrogens and peripheral arterial disease risk: the Women's Health Initiative.

BACKGROUND: Estradiol reduced progression of ultrasonographic carotid disease in a randomized trial. No trials of unopposed estrogen for prevention of lower extremity arterial disease or aortic aneurysm have been conducted. METHODS: The Estrogen Alone trial randomized 10739 postmenopausal women with prior hysterectomy, mean age 63.6 +/- 7.3 years, to conjugated equine estrogens (CEE 0.625 mg/d) or placebo and documented health outcomes over an average of 7.1 +/- 1.6 years. RESULTS: A trend toward increased risk of peripheral arterial events with CEE was observed (hazard ratio [HR] 1.32, 95% CI 0.99-1.77). Carotid arterial events (HR 1.19, 95% CI 0.82-1.74), lower extremity arterial events (HR 1.41, 95% CI 0.86-2.32), and abdominal aortic aneurysm (HR 2.40, 95% CI 0.92-6.23) were more frequent, but not individually significant, in the CEE group. However, the composite of lower extremity arterial disease/abdominal aortic aneurysm was significantly more frequent among women assigned to CEE (HR 1.63, 95 % CI 1.05-2.51). In subgroup analyses, no clear pattern of risk with CEE was apparent by age or by time since menopause. CONCLUSIONS: Unopposed CEE conferred no protection against peripheral arterial disease among generally healthy postmenopausal women; in fact, there was a suggestion of increased risk.

Aged↗
PubMed2006

Obesity, weight change, and functional decline in peripheral arterial disease.

BACKGROUND: Our objectives were to determine whether obesity is associated with a greater functional decline compared with the ideal body mass index (BMI) among persons with peripheral arterial disease (PAD) and to determine the associations between weight gain and loss and functional declines in PAD. We hypothesized that baseline obesity and weight gain during follow-up would each be associated with functional declines in persons with PAD. METHODS: The design was a prospective cohort study. The subjects were 389 men and women with PAD (mean ankle-brachial index, 0.65 +/- 0.14) who were followed up prospectively for a median of 48 months. The main outcome measures were functional assessments (6-minute walk, usual- and rapid-paced 4-m walking speed, and summary performance score). Weight and height were measured at baseline and annually. Results were adjusted for age, sex, race, comorbidities, ankle-brachial index, education, leg symptoms, exercise status, depressive symptoms, pack-years of cigarette smoking, prior-year functioning, and patterns of missing data. RESULTS: Compared with those with a baseline BMI between 20 and 25 kg/m2, PAD participants with baseline BMI greater than 30 kg/m2 had a significantly greater average annual decline in 6-minute walk performance (-13.1 vs -26.5 m/y; P = .004), usual-paced 4-m walking velocity (-0.028 vs -0.055 m/s per year; P = .024), and fast-paced 4-m walking velocity (-0.053 vs -0.086 m/s per year; P = .012). Persons with weight gain between 5 and 10 pounds after baseline who walked for exercise regularly had significantly less decline in the 6-minute walk than persons without significant weight change who did not walk for exercise (P = .04). CONCLUSIONS: Obesity is associated with functional decline in persons with PAD. Walking exercise may protect against functional decline in PAD persons with modest weight gain.

Aged↗
PubMed2006

Functional decline in patients with and without peripheral arterial disease: predictive value of annual changes in levels of C-reactive protein and D-dimer.

BACKGROUND: Inflammation may be a potential mechanism of aging-related functional decline. We determined whether greater annual increases in levels of high sensitivity C-reactive protein (hsCRP) and D-dimer predicted greater decline in functioning among persons with and without lower extremity peripheral arterial disease (PAD). METHODS: We prospectively studied 296 men and women with PAD and 191 without PAD. Objective measures of functioning, hsCRP, and D-dimer were obtained at baseline and annually for 3 years (mean follow-up = 36.3 +/- 6.4 months). RESULTS: Among PAD participants, greater annual increases in hsCRP were associated with greater annual declines in 6-minute walk performance (-2.63 ft/mg/L, p =.039) but not in other functional outcomes. Higher prior year absolute hsCRP levels were associated with greater declines in 6-minute walk (-2.93 ft/mg/L, p =.022), summary performance score (-0.038/mg/L, p =.017), and rapid paced 4-meter walk (-0.29 cm/s/mg/L, p =.026) during the subsequent year. Among participants without PAD, greater annual increases in hsCRP were associated with greater annual declines in 6-minute walk (-7.47 ft/mg/L, p =.002), usual-pace 4-meter walk (-0.33 cm/s/mg/L, p <.001), fast paced 4-meter walk (-0.56 cm/s/mg/L, p =.003), and the summary performance score (-0.029 mg/L, p <.001). There were no consistent associations between D-dimer levels and functional decline. CONCLUSION: These findings suggest that inflammation may play a role in functional decline in persons with and without PAD.

Aged↗
PubMed2005

Exertional leg pain in patients with and without peripheral arterial disease.

BACKGROUND: Although exertional leg pain is a hallmark of peripheral arterial disease (PAD) and can occur in persons without PAD, symptom variation has received inadequate attention. METHODS AND RESULTS: Three cohort studies were combined for cross-sectional analysis. The San Diego Claudication Questionnaire assessed exertional leg pain. PAD was defined as ankle brachial index (ABI) < or =0.90 or history of lower-extremity revascularization. Of 3658 subjects, 3629 were analyzed after exclusions. Of these, 24.1% had PAD in 1 or both legs. There was a stepwise decrease in average ABI, from no pain to pain on exertion and rest, noncalf pain, atypical calf pain, and classic claudication (P=0.002). When stratified by PAD, this trend was no longer significant. Legs with ABIs >0.90 and revascularization had pain distributions intermediate between that of normal legs (ABI, 1.00 to 1.39) and legs with ABIs < or =0.90. Compared with normal legs, legs with low-normal (0.91 to 0.99) and high-normal (> or =1.40) ABIs had higher pain rates, suggesting borderline disease and vascular stiffness, respectively. Multivariable logistic regression models showed that ABI was a strong correlate of pain category throughout the ABI range. Independently of ABI, age, male sex, diabetes, smoking history, high body mass index, myocardial infarction, and previous revascularization were all significant correlates of exertional leg pain. CONCLUSIONS: No category of exertional leg pain was sufficiently sensitive or specific for routine PAD diagnosis. Legs with low-normal and high-normal ABIs appeared to have ischemic leg pain; thus, a "normal ABI" is likely to range from 1.00 to 1.39. In addition to ABI, several risk variables were independent correlates of exertional leg pain.

Aged↗
PubMed2005

Ethnicity and peripheral arterial disease: the San Diego Population Study.

BACKGROUND: Previous studies have indicated higher rates of peripheral arterial disease (PAD) in blacks than in non-Hispanic whites (NHWs), with limited information available for Hispanics and Asians. The reason for the PAD excess in blacks is unclear. METHODS AND RESULTS: Ethnic-specific PAD prevalence rates were determined in a randomly selected defined population that included 4 ethnic groups; NHWs, blacks, Hispanics, and Asians. A total of 2343 participants aged 29 to 91 years were evaluated. There were 104 cases of PAD (4.4%). In weighted logistic models with NHWs as the reference group and containing demographic factors only, blacks had a higher PAD prevalence than NHWs (OR=2.30, P<0.024), whereas PAD rates in Hispanics and Asians, although somewhat lower, were not significantly different from NHWs. Blacks had significantly more diabetes and hypertension than NHWs and a significantly higher body mass index. Inclusion of these variables and other PAD risk factors in the model did not change the effect size for black ethnicity (OR=2.34, P=0.048). A model containing interaction terms for black ethnicity and each of the other risk factors revealed no significant interaction terms, which indicates no evidence that blacks were more "susceptible" than NHWs to cardiovascular disease risk factors. CONCLUSIONS: Black ethnicity was a strong and independent risk factor for PAD, which was not explained by higher levels of diabetes, hypertension, and body mass index. There was no evidence of a greater susceptibility of blacks to cardiovascular disease risk factors as a reason for their higher PAD prevalence. Thus, the excess risk of PAD in blacks remains unexplained and requires further study.

Aged↗
PubMed2005

Risk factors for declining ankle-brachial index in men and women 65 years or older: the Cardiovascular Health Study.

BACKGROUND: An ankle-brachial index (ABI) of less than 0.9 is a noninvasive measure of lower extremity arterial disease and a predictor of cardiovascular events. Little information is available on longitudinal change in ABI or on risk factors for declining ABI in a community-based population. METHODS: To assess risk factors for ABI decline, we studied 5888 participants in the Cardiovascular Health Study cohort (men and women 65 years or older). We measured ABI in 1992-1993 and again in 1998-1999. At baseline, we excluded individuals with an ABI less than 0.9, ABI greater than 1.4, or confirmed symptomatic lower extremity arterial disease (n = 823). The group with ABI decline included 218 participants with decline greater than 0.15 and to 0.9 or less. The comparison group comprised the remaining 2071 participants with follow-up ABI. RESULTS: The percentage of participants with ABI decline was 9.5% over 6 years of follow-up. The mean +/- SD decline was 0.33 +/- 0.12 in cases of ABI decline and 0.02 +/- 0.13 in non-cases. Independent predictors of ABI decline, reported as odds ratios, were age, 1.96 (95% confidence interval [CI], 1.42-2.71) for 75 to 84 years and 3.79 (95% CI, 1.36-10.5) for those older than 85 years compared with those younger than 75 years; current cigarette use, 1.74 (95% CI, 1.02-2.96); hypertension, 1.64 (95% CI, 1.18-2.28); diabetes, 1.77 (95% CI, 1.14-2.76); higher low-density lipoprotein cholesterol level, 1.60 (95% CI, 1.03-2.51), and lipid-lowering drug use 1.74 (95% CI, 1.05-2.89). CONCLUSION: Worsening lower extremity arterial disease, assessed as ABI decline, occurred in 9.5% of this elderly cohort over 6 years and was associated with modifiable vascular disease risk factors.

Aged↗
PubMed2005

Smoking, diabetes, and blood cholesterol differ in their associations with subclinical atherosclerosis: the Multiethnic Study of Atherosclerosis (MESA).

Previous reports suggest that low-density lipoprotein cholesterol (LDLc) is associated with atherosclerosis plaque initiation while cigarette smoking is more associated with plaque progression. The role of diabetes in plaque initiation and progression is not clear. The aim of this study was to confirm and extend these findings. Among 6384 men and women aged 45-84 free of clinical cardiovascular disease, subclinical atherosclerosis severity was classified on the basis of ultrasound measures of carotid stenosis and thickness and the ankle-brachial blood pressure index of lower extremity arterial disease. Carotid plaques were classified as echolucent or echogenic. Distensibility was calculated from the change in carotid diameter over the cardiac cycle. The smoking association with minimal, moderate, and more severe disease was progressive, estimated as equivalent to LDLc effects of 40, 85 and 238 mg/dl respectively. LDLc was relatively more associated with echolucent plaques; smoking with echogenic plaques. Diabetes was associated with carotid stiffness, whereas smoking was associated with greater distensibility. The results, together with pathological literature, suggest that LDLc may be of key importance both in plaque initiation and vulnerability to rupture, whereas smoking may relate to plaque progression to thicker, more fibrous lesions. Diabetes contributes uniquely to arterial stiffness.

Aged↗
PubMed2005

Ankle-brachial index and subclinical cardiac and carotid disease: the multi-ethnic study of atherosclerosis.

The authors studied associations between ankle-brachial index (ABI) and subclinical atherosclerosis in the Multi-Ethnic Study of Atherosclerosis. Participants included 3,458 women (average age = 62.6 years) and 3,112 men (average age = 62.8 years) who were free of clinically evident cardiovascular disease. Measurements included ABI, carotid artery intima-media thickness, and coronary artery calcium assessed with computed tomography. Five ABI categories were defined: <0.90 (definite peripheral arterial disease (PAD)), 0.90-0.99 (borderline ABI), 1.00-1.09 (low-normal ABI), 1.10-1.29 (normal ABI), and > or =1.30 (high ABI). Compared with that in men with normal ABI, significantly higher internal carotid artery intima-media thickness was observed in men with definite PAD (1.58 vs. 1.09; p < 0.001), borderline ABI (1.33 vs. 1.09; p < 0.001), and low-normal ABI (1.18 vs. 1.09; p < 0.001) after adjustment for confounders. Fully adjusted odds ratios for a coronary artery calcium score greater than 20 decreased across progressively higher ABI categories in both women (2.85 (definite PAD), 1.27 (borderline ABI), 1.11 (low-normal ABI), 1.00 (normal ABI; referent), and 0.78 (high ABI); p for trend = 0.0002) and men (3.26 (definite PAD), 1.72 (borderline ABI), 1.14 (low-normal ABI), 1.00 (normal ABI; referent), and 1.43 (high ABI); p for trend = 0.0002). These findings indicate excess coronary and carotid atherosclerosis at ABI values below 1.10 (men) and 1.00 (women) and may imply increased risk of cardiovascular events in persons with borderline and low-normal ABI.

Aged↗