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Michael H Criqui

Publications and source records attributed to Michael H Criqui.

At least 37 records · Page 2Linked to original sources
PubMed2005

Fasting triglyceride and the triglyceride-HDL cholesterol ratio are not markers of insulin resistance in African Americans.

BACKGROUND: The "lipid criteria" consist of a triglyceride (TG) level of 130 mg/dL (1.47 mmol/L) or greater and a ratio of TG to high-density lipoprotein cholesterol (HDL-C) of 3 or greater. In Caucasians, the lipid criteria predict insulin resistance in individuals with a body mass index (BMI) of 25 kg/m(2) or greater. Our goal was to determine whether TG levels or TG-HDL-C ratio predicted insulin resistance in African Americans with a BMI of 25 kg/m(2) or more. METHODS: Of 125 African Americans, the 98 with a BMI of 25 kg/m(2) or more participated. All subjects had frequently sampled intravenous glucose tolerance tests with insulin resistance determined by the insulin sensitivity index. Subjects were divided into the following tertiles by insulin sensitivity: 12.8 to 4.3, 4.2 to 2.3, and 2.2 to 0.2 mU/L per minute. Insulin resistance was defined as being in the third tertile. Across tertiles, the distribution of variables was compared by 1-way analysis of variance. Areas under the receiver operating characteristic curve were determined to identify variables that predicted insulin resistance. RESULTS: Fasting insulin level, BMI, and waist circumference increased across tertiles (all P<.01), but TG levels and TG-HDL-C ratio did not (all P>/=.3). The mean +/- SE areas under the curves for fasting insulin, BMI, and waist circumference were 0.85 +/- 0.04, 0.72 +/- 0.05, and 0.71 +/- 0.05, respectively. For TG level and TG-HDL-C ratio, the areas under the curves were 0.55 +/- 0.06 and 0.56 +/- 0.06, respectively, meaning that the true-positive rate was nearly equal to the false-positive rate. Therefore, they could not be used as markers of insulin resistance. Furthermore, 17 subjects met the lipid criteria but only 7 were in the insulin-resistant tertile, making the sensitivity of these criteria to identify insulin resistance only 17%. CONCLUSION: In African Americans, TG levels and TG-HDL-C ratio are not reliable markers of insulin resistance.

Adult↗
PubMed2005

Relationships between symptoms and venous disease: the San Diego population study.

BACKGROUND: The associations between symptoms and venous disease of the lower extremities are poorly characterized. METHODS: We conducted a cross-sectional study to evaluate relationships between symptoms associated with venous disease and prevalent disease in 2408 men and women aged 29 to 91 years who were employees, retirees, or spouses at a large state university. Index participants were randomly selected within strata by age, sex, and ethnicity. A structured interview assessed the prevalence of aching, itching, heaviness, tired legs, cramping, swelling, and nighttime restless legs. A comprehensive standardized examination determined the prevalence of visible disease (normal, telangiectasias, varicose veins, and trophic changes) and functional disease (normal, superficial, and deep disease). We related symptoms to disease with attention to modification by sex, ethnicity, and age. RESULTS: Aching, itching, heaviness, tired legs, cramping, and swelling were related to both superficial and deep functional disease. The same symptoms were related to varicose veins and trophic changes. Swelling and heaviness were related to telangiectatic disease. Except for restless legs and trophic changes, the prevalence of symptoms across each category was greater in women than men. Aching was the most common symptom but was relatively nonspecific. Swelling was the most specific marker for prevalent visible and functional disease. Heaviness and itching also helped to distinguish prevalent disease. CONCLUSIONS: Venous symptoms were more prevalent in study participants with both visible and functional disease and in women. Swelling was the most specific predictor; heaviness, itching, and aching also helped to distinguish cases.

Adult↗
PubMed2005

Relationship of monocyte count and peripheral arterial disease: results from the National Health and Nutrition Examination Survey 1999-2002.

BACKGROUND: Although white blood cell (WBC) count has been consistently associated with cardiovascular end points, little information is available on the independent contribution of specific white blood cell types. The objective of this study is to assess the independent association of WBC types and other inflammatory markers with the presence of reduced ankle-brachial blood pressure index (ABI), a marker of subclinical peripheral arterial disease (PAD). METHODS & RESULTS: Cross-sectional study in 3949 individuals > or =40 years of age without known cardiovascular disease who participated in the 1999 to 2002 National Health and Nutrition Examination Survey (NHANES). PAD was defined as an ABI <0.9 in at least 1 leg. After adjustment for traditional cardiovascular risk factors, the odds ratios of PAD comparing the highest to the lowest quartiles were 2.24 (95% confidence interval 1.24 to 4.04) for monocytes, 1.74 (0.87 to 3.45) for neutrophils, 2.53 (1.62 to 3.96) for C-reactive protein, and 2.68 (1.03 to 6.94) for fibrinogen. When WBC types and inflammatory markers were simultaneously included in the full model, the corresponding odds ratios were 1.91 (95% confidence interval 1.06 to 3.42) for monocytes, 1.15 (0.49 to 2.69) for neutrophils, 1.37 (0.75 to 2.49) for C-reactive protein, and 2.21 (0.88 to 5.57) for fibrinogen. CONCLUSIONS: Monocytes were the only WBC type significantly and independently associated with PAD in a representative sample of the U.S. population after adjustment for other inflammatory markers. These findings reflect the potential role of circulating monocyte counts as markers of atherosclerosis.

Aged↗
PubMed2005

Functional decline in lower-extremity peripheral arterial disease: associations with comorbidity, gender, and race.

PURPOSE: To identify comorbidities associated with increased rates of functional decline in persons with lower-extremity peripheral arterial disease (PAD). We also determined whether female sex and black race were associated with greater functional decline than male sex and white race, respectively, in PAD. METHODS: Three-hundred ninety-seven men and women with PAD were followed prospectively for a median of 36 months. The presence of comorbid illnesses was determined with medical record review, patient report, medications, laboratory values, and a primary care physician questionnaire. Functional outcomes, measured annually, included the 6-minute walk, usual-paced and fast-paced 4-meter walking speed, and summary performance score. The summary performance score is a composite measure of lower-extremity functioning (score range, 0 to 12; 12 = best). RESULTS: Adjusting for known and potential confounders, PAD patients with pulmonary disease had a significantly greater average annual decline in 6-minute walk performance of -34.02 ft/y (95% confidence interval [CI], -60.42 to -7.63; P = .012), rapid-paced 4-meter walk speed of -0.028 m/s/y (95% CI, -0.054 to -0.001; P = .042), and summary performance score of -0.460/y (95% CI, -0.762 to -0.157; P = .003) compared with those without pulmonary disease. PAD patients with spinal stenosis had a greater average annual decline in 6-minute walk performance of -77.4 ft/y (95% CI, -18.9 to -35.8; P < .001) and usual-paced 4-meter walking velocity of -0.045 m/s/y (95% CI, -0.081 to -0.009; P = .014) compared with participants without spinal stenosis. CONCLUSION: At 3-year follow-up, pulmonary disease and spinal stenosis were each associated with a significant decline in functioning among persons with PAD. In contrast, female sex and black race were not associated with functional decline among persons with PAD.

Aged↗
PubMed2005

D-dimer and inflammatory markers as predictors of functional decline in men and women with and without peripheral arterial disease.

OBJECTIVES: To determine whether higher circulating levels of inflammatory and thrombotic markers are associated with greater decline in lower extremity performance. DESIGN: Prospective cohort. SETTING: Academic medical center. PARTICIPANTS: Three hundred thirty-seven men and women with lower extremity peripheral arterial disease (PAD) and 215 without PAD. MEASUREMENTS: Objective measures of leg function, including the 6-minute walk and Short Physical Performance Battery (SPPB), were obtained at baseline and annually for 3 years. D-dimer, high-sensitivity C-reactive protein, serum amyloid A, and fibrinogen levels were measured at baseline. Participants were categorized into one of three groups, ranging from low to high levels of inflammation, depending on the number of individual blood factors in the lowest and highest tertiles for each corresponding blood factor. RESULTS: Adjusting for age, sex, race, ankle brachial index, comorbidities, and other confounders, greater inflammation was associated with greater decline in the SPPB (P=.008). Results were similar when repeated in participants with and without PAD separately (P for trend=.04 for participants with PAD and .07 for participants without PAD). In fully adjusted analyses, there were no significant associations between inflammation group and decline in 6-minute walk performance. CONCLUSION: Higher baseline levels of inflammatory markers and D-dimer were associated with greater decline in the SPPB at 3-year follow-up in persons with and without PAD.

Activities of Daily Living↗
PubMed2004

CDC/AHA Workshop on Markers of Inflammation and Cardiovascular Disease: Application to Clinical and Public Health Practice: report from the population science discussion group.

This article summarizes epidemiological studies of inflammation markers, particularly C-reactive protein, and cardiovascular disease as of early 2002. Gaps in the research and the public health practice implications are also discussed. Although considerable work has been published since this review was completed, the perspectives and issues presented are still useful in evaluating the use of inflammation markers for risk stratisfication and prevention.

Biomarkers↗
PubMed2004

Subclavian artery stenosis: prevalence, risk factors, and association with cardiovascular diseases.

OBJECTIVES: The objective was to assess the prevalence of subclavian artery stenosis (SS) in four cohorts (two free-living and two clinical populations) and determine both risk factors for this condition and the association with other cardiovascular conditions. BACKGROUND: The prevalence of SS in the general population is unknown, and its association with risk factors and other cardiovascular diseases is not well-established. METHODS: A total of 4,223 subjects (2,975 from two free-living cohorts and 1,248 from two clinical cohorts) were included in this cross-sectional analysis. Subclavian artery stenosis was defined as > or =15 mm Hg interarm pressure difference. RESULTS: The prevalence of SS was 1.9% in the free-living cohorts and 7.1% in the clinical cohorts; SS was significantly (p < 0.05) associated with past smoking (odds ratio [OR] = 1.80), current smoking (OR = 2.61), and higher levels of systolic blood pressure (OR = 1.90 per 20 mm Hg). Higher levels of high-density lipoprotein (HDL) cholesterol were inversely and significantly associated with SS (OR = 0.87 per 10 mg/dl). In regression analyses relating SS to other cardiovascular diseases, the only significant finding was with peripheral arterial disease (PAD) (OR = 5.11, p < 0.001). CONCLUSIONS: Significant SS is present in approximately 2% of the free-living population and 7% of the clinical population. Additionally, SS is correlated with current and past smoking histories, systolic blood pressure, HDL levels (inversely), and the presence of PAD. These findings suggest that bilateral brachial blood pressure measurements should routinely be performed in patients with an elevated risk profile, both to screen for SS, and to avoid missing a hypertension or PAD diagnosis because of unilateral pressure measurement in an obstructed arm.

Aged↗
PubMed2004

Functional decline in peripheral arterial disease: associations with the ankle brachial index and leg symptoms.

CONTEXT: Among individuals with lower-extremity peripheral arterial disease (PAD), specific leg symptoms and the ankle brachial index (ABI) are cross-sectionally related to the degree of functional impairment. However, relations between these clinical characteristics and objectively measured functional decline are unknown. OBJECTIVE: To define whether PAD, ABI, and specific leg symptoms predict functional decline at 2-year follow-up. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study among 676 consecutively identified individuals (aged > or =55 years) with and without PAD (n = 417 and n = 259, respectively), with baseline functional assessments occurring between October 1, 1998, and January 31, 2000, and follow-up assessments scheduled 1 and 2 years thereafter. PAD was defined as ABI less than 0.90, and participants with PAD were categorized at baseline into 1 of 5 mutually exclusive symptom groups. MAIN OUTCOME MEASURES: Mean annual changes in 6-minute walk performance and in usual-paced and fast-paced 4-m walking velocity, adjusted for age, sex, race, prior-year functioning, comorbid diseases, body mass index, pack-years of cigarette smoking, and patterns of missing data. RESULTS: Lower baseline ABI values were associated with greater mean (95% confidence interval) annual decline in 6-minute walk performance (-73.0 [-142 to -4.2] ft for ABI <0.50 vs -58.8 [-83.5 to -34.0] ft for ABI 0.50 to <0.90 vs -12.6 [-40.3 to 15.1] ft for ABI 0.90-1.50, P =.02). Compared with participants without PAD, PAD participants with leg pain on exertion and rest at baseline had greater mean annual decline in 6-minute walk performance (-111 [-173 to -50.0] ft vs -8.67 [-36.9 to 19.5] ft, P =.004), usual-pace 4-meter walking velocity (-0.06 [-0.09 to -0.02] m/sec vs -0.01 (-0.03 to 0.003] m/sec, P =.02), and fastest-pace 4-meter walking velocity (-0.07 [-0.11 to -0.03] m/sec vs -0.02 [-0.04 to -0.006] m/sec, P =.046). Compared with participants without PAD, asymptomatic PAD was associated with greater mean annual decline in 6-minute walk performance (-76.8 (-135 to -18.6] ft vs -8.67 (-36.9 to 19.5] ft, P =.04) and an increased odds ratio for becoming unable to walk for 6 minutes continuously (3.63; 95% confidence interval, 1.58-8.36; P =.002). CONCLUSIONS: Baseline ABI and the nature of leg symptoms predict the degree of functional decline at 2-year follow-up. Previously reported lack of worsening in claudication symptoms over time in patients with PAD may be more related to declining functional performance to than lack of disease progression.

Activities of Daily Living↗
PubMed2004

Estrogen plus progestin and the risk of peripheral arterial disease: the Women's Health Initiative.

BACKGROUND: Observational studies have reported less frequent carotid atherosclerosis in healthy women taking postmenopausal hormone therapy. Estrogen with progestin did not reduce peripheral arterial events among women with preexisting coronary heart disease. This analysis evaluates clinical peripheral arterial disease among generally healthy women in the Women's Health Initiative randomized trial of estrogen plus progestin. METHODS AND RESULTS: The Estrogen Plus Progestin trial assigned 16 608 postmenopausal women, mean age 63.3+/-7.1 years, to daily conjugated estrogens (0.625 mg) with medroxyprogesterone acetate (2.5 mg) or placebo and documented health outcomes over an average of 5.6 years of follow-up. Hospitalization for peripheral arterial disease was infrequent, with annualized rates of 0.08%, 0.06%, and 0.02% for carotid disease, lower extremity arterial disease, and abdominal aortic aneurysm, respectively. The incidence of peripheral arterial events did not differ between treatment groups (hazard ratio [HR] 0.89, 95% confidence interval 0.63, 1.25). The risk was slightly greater among women assigned to active estrogen with progestin in years 1 (HR 1.33) and 2 (HR 1.27), and was slightly lower in later years (HR 0.85 and 0.87 in years 5 and > or =6). Among adherent participants, the hazard ratio for peripheral arterial events was 1.23 (95% confidence interval 0.79, 1.91) over the 5.6 years of follow up. Subgroup analysis identified no significant interactions between estrogen with progestin and baseline characteristics with regard to peripheral arterial disease risk. CONCLUSIONS: Among generally healthy postmenopausal women, conjugated estrogens with progestin did not confer protection against peripheral arterial disease.

Aged↗
PubMed2004

Conceptual foundations of the UCSD Statin Study: a randomized controlled trial assessing the impact of statins on cognition, behavior, and biochemistry.

BACKGROUND: Statin cholesterol-lowering drugs are among the most prescribed drugs in the United States. Their cardiac benefits are substantial and well supported. However, there has been persistent controversy regarding possible favorable or adverse effects of statins or of cholesterol reduction on cognition, mood, and behavior (including aggressive or violent behavior). METHODS: The literature pertaining to the relationship of cholesterol or statins to several noncardiac domains was reviewed, including the link between statins (or cholesterol) and cognition, aggression, and serotonin. RESULTS: There are reasons to think both favorable and adverse effects of statins and low cholesterol on cognition may pertain; the balance of these factors requires further elucidation. A substantial body of literature links low cholesterol level to aggressive behavior; statin randomized trials have not supported a connection, but they have not been designed to address this issue. A limited number of reports suggest a connection between reduced cholesterol level and reduced serotonin level, but more information is needed with serotonin measures that are practical for clinical use. Whether lipophilic and hydrophilic statins differ in their impact should be assessed. CONCLUSION: There is a strong need for randomized controlled trial data to more clearly establish the impact of hydrophilic and lipophilic statins on cognition, aggression, and serotonin, as well as on other measures relevant to risks and quality-of-life impact in noncardiac domains.

Aggression↗
PubMed2004

The UCSD Statin Study: a randomized controlled trial assessing the impact of statins on selected noncardiac outcomes.

There has been persistent controversy regarding possible favorable or adverse effects of statins or of cholesterol reduction on cognition, mood and behavior (including aggressive or violent behavior), muscle function, and quality of life. The UCSD Statin Study seeks to ascertain the beneficial or adverse effects of statin cholesterol-lowering drugs on a set of noncardiac endpoints, including cognition, behavior, and serotonin biochemistry. The study will enroll 1000 subjects (minimum 20% female) of mixed ethnicity from San Diego. Subjects must be age 20 and older, postmenopausal if female, without known cardiovascular disease or diabetes, and with LDL-cholesterol between 115 and 190 mg/dl. Subjects will be randomized to a double-blind, placebo-controlled trial with assignment 1/3, 1/3, 1/3 to placebo, simvastatin 20 mg, or pravastatin 40 mg (equipotent LDL-cholesterol-lowering doses for drug arms with simvastatin and pravastatin chosen to represent the extremes of the lipophilicity spectrum) for 6 months of treatment followed by 2 months postcessation follow-up. Primary outcomes are cognition (cognitive battery), irritability/aggression (behavior measure), and serotonin (gauged by whole blood serotonin), assessed as the difference between baseline and 6 months, judging combined statin groups vs. placebo. Secondary outcomes include mood (CES-D and Wakefield depression inventory), quality of life (SF-12V), sleep (Leeds sleep scale, modified), and secondary aggression measures (Conflict Tactics Scale; Overt Aggression Scale, Modified). Cardiovascular reactivity will be examined in a 10% subset. As additional secondary endpoints, primary and selected secondary outcomes will be assessed by statin assignment (lipophilic simvastatin vs. hydrophilic pravastatin). "Reversibility" of changes, if any, at 2 months postcessation will be determined. If effects (favorable or unfavorable) are identified, we will seek to ascertain whether there are baseline variables that predict who will be most susceptible to these favorable or adverse noncardiac effects (i.e., effect modification).

Adult↗
PubMed2004

Leg strength in peripheral arterial disease: associations with disease severity and lower-extremity performance.

OBJECTIVE: The purpose of this study was to determine relationships between lower-extremity arterial obstruction, leg strength, and lower-extremity functioning. DESIGN: The study design was cross-sectional. A total of 514 outpatients (269 with ankle-brachial index [ABI] <0.90), aged 55 and older, were identified from three Chicago-area hospitals. Individuals with history of lower-extremity revascularization were excluded. Main outcome measures Strength in each leg, 6-minute walk, 4-meter walking velocity, accelerometer-measured physical activity, and a summary performance score were measured. The summary performance score is a composite measure of lower-extremity functioning, ranging from 0 to 12 (12 = best). The leg with the lower ABI was defined as the "index" leg, and the leg with higher ABI was defined as the "contralateral" leg. RESULTS: Index leg ABI levels were associated linearly and significantly with strength for hip extension (P <.001), hip flexion (P <.001), knee extension (P =.066), and knee flexion (P =.003), adjusting for known and potential confounders. In adjusted analyses, the index ABI was also associated linearly and significantly with strength in the contralateral leg. Adjusting for confounders, including ABI, knee extension strength, was associated independently with functional measures. CONCLUSION: Among patients without prior leg revascularization, strength in each leg is highly correlated with the lower-leg ABI. Leg strength is associated independently with functional performance. Further study is needed to determine whether lower-extremity resistance training improves functioning in patients with peripheral arterial disease.

Aged↗
PubMed2004

Peripheral arterial disease in African Americans: clinical characteristics, leg symptoms, and lower extremity functioning.

OBJECTIVES: The describe peripheral arterial disease (PAD) in African Americans, and compare findings in African Americans and whites with PAD. DESIGN: Cross-sectional. SETTING: Three academic medical centers. PARTICIPANTS: Three hundred sixty-six whites and 76 African Americans with PAD (as defined by an ankle brachial index (ABI) <0.90) aged 55 and older identified from lower extremity arterial studies performed between 1996 and the fall of 1999. MEASUREMENTS: Comprehensive medical interview, body mass index, and neuropathy score. Functional measurements included the 6-minute walk distance, 4-m walking velocity, and the summary performance score. RESULTS: Age- and sex-adjusted results showed that African Americans had a lower mean ABI than whites (0.60 vs 0.66, P=.001), were less likely to be college graduates (13.7% vs 44.4%, P<.001), and had nearly twice the prevalence of diabetes mellitus (46.8% vs 28.0%, P=.001). After adjusting for age, sex, education level, and ABI, African Americans had a higher prevalence of no exertional leg pain (28.0% vs 18.2%, P=.044) and leg pain with exertion and rest (30.0% vs 17.3%, P=.023). African Americans had a shorter 6-minute walk distance (989 vs 1,156 ft, P<.001), a slower normal-pace 4-m walking velocity (0.79 vs 0.89 m/s, P<.001), a slower fast-pace 4-m walking velocity (1.12 vs 1.20 m/s, P=.012), and a lower summary performance score (8.8 vs 9.6, P=.018) than whites. These differences in functioning were attenuated after adjusting for age, sex, ABI, education, and leg symptoms. CONCLUSION: Poorer lower extremity functioning in African Americans was largely explained by differences in leg symptoms and, to a somewhat lesser degree, lower ABI levels and poorer education in African Americans than in whites. Further study is needed to determine whether these findings affect racial treatment disparities and poorer outcomes previously reported in African Americans than in whites with PAD.

Black or African American↗
PubMed2004

Inflammatory and thrombotic blood markers and walking-related disability in men and women with and without peripheral arterial disease.

OBJECTIVES: To determine whether higher circulating levels of thrombotic and inflammatory markers are associated with greater disability. DESIGN: Cross-sectional. SETTING: Academic medical center. PARTICIPANTS: A total of 346 men and women with peripheral arterial disease (PAD) and 203 without PAD. MEASUREMENTS: Disability measures were the Walking Impairment Questionnaire (WIQ) distance, speed, and stair-climbing scores and the 36-item Short-Form (SF-36) physical functioning score. The SF-36 and WIQ are scored on a 0 to 100 scale (100=best). RESULTS: In persons with PAD, higher D-dimer levels were associated with lower WIQ speed scores (P<.001), lower stair-climbing scores (P<.04), and poorer SF-36 physical functioning scores (P<.01), adjusting for known and potential confounders. In participants without PAD, higher D-dimer levels were associated with lower WIQ distance scores (P<.03), lower speed scores (P<.05), and poorer SF-36 physical functioning scores (P<.02). Higher high-sensitivity C-reactive protein (hsCRP) levels were associated with lower WIQ distance (P<.02) and speed scores (P<.001) in persons without PAD. Most of these associations were attenuated after additional adjustment for objectively measured functional limitations. CONCLUSION: Higher circulating D-dimer and hsCRP levels are associated with greater disability in walking and physical functioning in individuals with and without PAD. Physiological changes that result in walking disability may mediate these associations.

Aged↗