K Liu

Northwestern University, Evanston, Illinois, United States

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Publications (109)816.42 Total impact

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    ABSTRACT: To examine the association between changes in procoagulants (fibrinogen factors VII and VIII and von Willebrand factor) and the risk of insulin resistance. Using data from the Coronary Artery Risk Development in Young Adults study, we followed 2398 black and white adults without diabetes, aged 25-37 years at year 7, to year 20. Levels of fibrinogen factors VII and VIII and von Willebrand factor were divided in tertiles (low/middle/high) at years 7 and 20 and four groups reflecting changes were defined: 'low' (low at years 7 and 20), 'stable' (low/middle at years 7 and 20, but not both low at years 7 and 20), 'high' (high at year 7 and low/middle at year 20; or low/middle at year 7 and high at year 20) and 'highest' (high at years 7 and 20). Linear regression models were used to evaluate 13-year changes (year 20-year 7) in fibrinogen level and factors VII, VIII and von Willebrand change groups in relation to insulin resistance measures. Homeostasis model assessment of insulin resistance (year 20) and changes in log homeostasis model assessment of insulin resistance (year 20-year 7) were significantly associated with the 13-year increase in fibrinogen (P < 0.001). Compared with participants in the low group, those in the high group had significantly higher levels of homeostasis model assessment of insulin resistance (year 20) and changes in homeostasis model assessment of insulin resistance (year 20-year 7) for fibrinogen factor VII and von Willebrand factor (P < 0.017). No significant associations were observed between fibrinogen VIII and insulin resistance measures. An increase in fibrinogen level and persistently high levels of factor VII and von Willebrand factor are significantly associated with increased risk of insulin resistance. These findings provide new insight into the mechanisms to explain the heightened risk for thrombosis in adults with insulin resistance/diabetes. This article is protected by copyright. All rights reserved.
    Diabetic Medicine 12/2013; · 3.24 Impact Factor
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    ABSTRACT: High blood pressure (BP) is more prevalent and contributes to more severe manifestations of cardiovascular disease (CVD) in African Americans than in any other United States ethnic group. Several small African-ancestry (AA) BP genome-wide association studies (GWASs) have been published, but their findings have failed to replicate to date. We report on a large AA BP GWAS meta-analysis that includes 29,378 individuals from 19 discovery cohorts and subsequent replication in additional samples of AA (n = 10,386), European ancestry (EA) (n = 69,395), and East Asian ancestry (n = 19,601). Five loci (EVX1-HOXA, ULK4, RSPO3, PLEKHG1, and SOX6) reached genome-wide significance (p < 1.0 x 10(-8)) for either systolic or diastolic BP in a transethnic meta-analysis after correction for multiple testing. Three of these BP loci (EVX1-HOXA, RSPO3, and PLEKHG1) lack previous associations with BP. We also identified one independent signal in a known BP locus (SOX6) and provide evidence for fine mapping in four additional validated BP loci. We also demonstrate that validated EA BP GWAS loci, considered jointly, show significant effects in AA samples. Consequently, these findings suggest that BP loci might have universal effects across studied populations, demonstrating that multiethnic samples are an essential component in identifying, fine mapping, and understanding their trait variability.
    The American Journal of Human Genetics 01/2013; 93(3):545-54. · 11.20 Impact Factor
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    ABSTRACT: Serum potassium has been found to be a significant predictor of diabetes risk, but the effect of dietary potassium on diabetes risk is not clear. We sought to determine if dietary potassium is associated with risk of incident type 2 diabetes in young adults. We used data from the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Potassium intake was measured by (1) an average of three 24 h urinary potassium collections at the 5-year study visit, and (2) the CARDIA dietary assessment instrument at baseline. Incident type 2 diabetes cases were ascertained on the basis of use of diabetes medication and laboratory measurements. Analyses were adjusted for relevant confounders including intake of fruit and vegetables and other dietary factors. Of 1,066 participants with urinary potassium measurements, 99 (9.3%) developed diabetes over 15 years of follow-up. In multivariate models, adults in the lowest urinary potassium quintile were more than twice as likely to develop diabetes as their counterparts in the highest quintile (HR 2.45; 95% CI 1.08, 5.59). Of 4,754 participants with dietary history measurements, 373 (7.8%) developed diabetes over 20 years of follow-up. In multivariate models, African-Americans had a significantly increased risk of diabetes with lower potassium intake, which was not found in whites. Low dietary potassium is associated with increased risk of incident diabetes in African-Americans. Randomised clinical trials are needed to determine if potassium supplementation, from either dietary or pharmacological sources, could reduce the risk of diabetes, particularly in higher-risk populations.
    Diabetologia 02/2012; 55(5):1295-303. · 6.49 Impact Factor
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    ABSTRACT: OBJECTIVE:Waist-to-hip ratio (WHR) is strongly associated with prevalent atherosclerosis. We analyzed the associations of baseline serum levels of testosterone (T), estradiol (E2), sex-hormone-binding globulin (SHBG) and dehydroepiandrosterone (DHEA) with WHR in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort.SUBJECTS:Baseline data was available for 3144 men and 2038 postmenopausal women, who were non-users of hormone therapy, who were 45-84 years of age, and of White, Chinese, Black or Hispanic racial/ethnic groups. Of these, 2708 men and 1678 women also had longitudinal measurements of WHR measured at the second and/or the third study visits (median follow-up 578 days and 1135 days, respectively).RESULTS:In cross-sectional analyses adjusted for age, race and cardiovascular disease risk factors, T was negatively associated with baseline WHR in men, whereas in both sexes, E2 was positively associated and SHBG was negatively associated with WHR (all P<0.001). In longitudinal analyses, further adjusted for follow-up time and baseline WHR, baseline T was negatively associated with WHR at follow-up (P=0.001) in men, whereas in both sexes, E2 was positively associated (P=0.004) and SHBG was negatively associated with WHR (P<0.001). The longitudinal association of E2, but not T, was independent of SHBG. In cross-sectional or longitudinal analyses, there were no associations between DHEA and WHR in either men or women.CONCLUSION:Sex hormones are associated with WHR at baseline and also during follow-up above and beyond their baseline association. Future research is needed to determine if manipulation of hormones is associated with changes in central obesity.International Journal of Obesity advance online publication, 24 January 2012; doi:10.1038/ijo.2012.3.
    International journal of obesity (2005) 01/2012; · 5.22 Impact Factor
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    ABSTRACT: It has been recognized that certain long-chain polyunsaturated fatty acids (LC-PUFAs) are involved in inflammation and its resolution. It has also been shown that ethnicity may be a factor in affecting systemic inflammation, and limited evidence suggests it may influence plasma LC-PUFA composition. Given the links among these three factors, we aim to determine ethnicity-based differences in plasma LC-PUFA composition among White, Black, Hispanic and Chinese participants, and whether such differences contribute to variations in markers of inflammation and endothelial activation in a sub-cohort of the Multi-Ethnic Study of Atherosclerosis (MESA). Plasma phospholipid LC-PUFAs levels (%) were determined in 2848 MESA participants using gas chromatography-flame ionization detection. Enzyme immunoassays determined inflammatory markers levels for high-sensitivity C-reactive protein (n=2848), interleukin-6 (n=2796), soluble tumor necrosis factor-α receptor type 1 (n=998), and endothelial activation markers soluble intercellular adhesion molecule-1 (n=1192) and soluble E-selectin (n=998). The modifying influence of ethnicity was tested by linear regression analysis. Chinese adults were found to have the highest mean levels of plasma eicosapentaenoic acid (EPA, 1.24%) and docosahexaenoic acid (DHA, 4.95%), and the lowest mean levels of γ-linolenic (0.10%), dihomo-γ-linolenic (DGLA, 2.96%) and arachidonic (10.72%) acids compared with the other ethnicities (all P ≤ 0.01). In contrast, Hispanics had the lowest mean levels of plasma EPA (0.70%) and DHA (3.49%), and the highest levels of DGLA (3.59%; all P ≤ 0.01). Significant differences in EPA and DHA among ethnicities were attenuated following adjustment for dietary non-fried fish and fish oil supplementation. Ethnicity did not modify the associations of LC-PUFAs with markers of inflammation or endothelial activation (all P (interaction)>0.05). The absence of a modifying effect of ethnicity indicates that the putative benefits of LC-PUFAs with respect to inflammation are pan-ethnic. Future longitudinal studies may elucidate the origin(s) of ethnicity-based differences in LC-PUFA composition and whether certain patterns, that is, high plasma levels of DGLA and low levels of EPA/DHA, contribute to inflammation-associated health outcomes.
    European journal of clinical nutrition 01/2012; 66(5):600-5. · 3.07 Impact Factor
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    ABSTRACT: Coronary artery disease (CAD) has a significant genetic contribution that is incompletely characterized. To complement genome-wide association (GWA) studies, we conducted a large and systematic candidate gene study of CAD susceptibility, including analysis of many uncommon and functional variants. We examined 49,094 genetic variants in ∼2,100 genes of cardiovascular relevance, using a customised gene array in 15,596 CAD cases and 34,992 controls (11,202 cases and 30,733 controls of European descent; 4,394 cases and 4,259 controls of South Asian origin). We attempted to replicate putative novel associations in an additional 17,121 CAD cases and 40,473 controls. Potential mechanisms through which the novel variants could affect CAD risk were explored through association tests with vascular risk factors and gene expression. We confirmed associations of several previously known CAD susceptibility loci (eg, 9p21.3:p<10(-33); LPA:p<10(-19); 1p13.3:p<10(-17)) as well as three recently discovered loci (COL4A1/COL4A2, ZC3HC1, CYP17A1:p<5×10(-7)). However, we found essentially null results for most previously suggested CAD candidate genes. In our replication study of 24 promising common variants, we identified novel associations of variants in or near LIPA, IL5, TRIB1, and ABCG5/ABCG8, with per-allele odds ratios for CAD risk with each of the novel variants ranging from 1.06-1.09. Associations with variants at LIPA, TRIB1, and ABCG5/ABCG8 were supported by gene expression data or effects on lipid levels. Apart from the previously reported variants in LPA, none of the other ∼4,500 low frequency and functional variants showed a strong effect. Associations in South Asians did not differ appreciably from those in Europeans, except for 9p21.3 (per-allele odds ratio: 1.14 versus 1.27 respectively; P for heterogeneity = 0.003). This large-scale gene-centric analysis has identified several novel genes for CAD that relate to diverse biochemical and cellular functions and clarified the literature with regard to many previously suggested genes.
    PLoS Genet. 09/2011; 7(9):e1002260..
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    ABSTRACT: The expanding overweight and obesity epidemic notwithstanding, little is known about their long-term effect on health-related quality of life (HRQoL). The main objective of this study was to investigate whether overweight (body mass index (BMI) 25 to <30 kg m(-2)) and obese (BMI ≥ 30 kg m(-2)) young adults have poorer HRQoL 20 years later. We studied 3014 participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study, a longitudinal, community-dwelling, biracial cohort from four cities. BMI was measured at baseline and 20 years later. HRQoL was assessed by the Physical Component Summary (PCS) and the Mental Component Summary (MCS) scores of the Medical Outcomes Study 12-Item Short-Form Health Survey at year 20. Higher PCS or MCS scores indicate better HRQoL. Mean year 20 PCS score was 52.2 for normal weight participants at baseline, 50.3 for overweight and 46.4 for obese (P-trend <0.001). This relation persisted after adjustment for baseline demographics, general health, and physical and behavioral risk factors and after further adjustment for 20-year changes in risk factors. No association was observed for MCS scores (P-trend 0.43). Overweight and obesity in early adulthood are adversely associated with self-reported physical HRQoL, but not mental HRQoL 20 years later.
    International journal of obesity (2005) 01/2011; 35(1):134-41. · 5.22 Impact Factor
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    Hum Mol Genet. 01/2011; 20:2273-84.
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    ABSTRACT: Long-chain omega-3 polyunsaturated fatty acids (LCω3PUFAs), selenium (Se) and mercury (Hg) are three important components in fish. The cardioprotective effect of LCω3PUFA intake has been recognized; however, the hypothesis that this benefit may be greatest with high Se and low Hg levels has not been investigated. A cohort of 4508 American adults aged 18-30, without hypertension at baseline in 1985, were enrolled. Six follow-ups were conducted at examinations in 1987, 1990, 1992, 1995, 2000 and 2005. Diet was assessed by a validated interviewer-administered quantitative food frequency questionnaire at exams in 1985, 1992 and 2005. Incident hypertension was defined as first occurrence at any follow-up examination of systolic blood pressure (BP) ≥ 140 mmHg, diastolic BP ≥ 90 mmHg or taking antihypertensive medication. Toenail clippings were collected in 1987, and Se and Hg levels were quantified by instrumental neutron-activation analysis. Participants in the highest LCω3PUFA intake quartile had a significantly lower incidence of hypertension (hazard ratio: 0.65; 95% CI: 0.53-0.79; P(trend) < 0.01) compared to those in the lowest quartile after adjustment for potential confounders. Docosahexaenoic acid showed a greater inverse association than eicosapentaenoic acid. The inverse association of LCω3PUFA intake with hypertension appeared more pronounced at higher Se and lower Hg levels, although interaction tests were statistically nonsignificant. Our findings indicated that LCω3PUFA intake was inversely associated with incidence of hypertension. The prior hypothesis that the potential antihypertensive effect of LCω3PUFA intake varies depending on joint levels of Se and Hg received modest support and cannot be ruled out.
    Journal of Internal Medicine 12/2010; 270(2):175-86. · 6.46 Impact Factor
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    ABSTRACT: To examine the strength of the associations of fibrinogen with subclinical atherosclerosis in healthy persons. A population-based, prospective, observational study of black and white men and women (Coronary Artery Risk Development in Young Adults [CARDIA]). Fibrinogen levels were measured at year 7 (ages 25-37, n = 2969), and again at year 20 (ages 38-50, n = 2832). Measures of subclinical atherosclerosis (coronary artery calcification [CAC] and carotid intimal-medial thickness [CIMT]) were recorded at year 20. Over the 13-year study interval (1992-1993 to 2005-2006), fibrinogen rose from a mean of 3.32 to 4.05 g L(-1). After adjusting for age, gender and race, fibrinogen was positively associated with greater incidence of CAC and increased CIMT cross-sectionally as well as after 13 years of follow-up (all P-trend < 0.001). After further adjustment for field center, BMI, smoking, education, systolic blood pressure, diabetes, antihypertensive medication use, total and HDL cholesterol, and CRP, significant positive relationships between fibrinogen and incidence of CAC remained for the total cohort longitudinally (P-trend = 0.037), but not cross-sectionally (P-trend = 0.147). This 13-year study demonstrates that higher levels of fibrinogen during young adulthood are positively associated with incidence of CAC and increased CIMT in middle-age, but the strength of the association declines with increasing age.
    Journal of Thrombosis and Haemostasis 12/2009; 8(3):489-95. · 6.08 Impact Factor
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    ABSTRACT: To compare age-associated 8-year changes in total testosterone, calculated bioavailable testosterone and sex hormone binding globulin (SHBG) across five groups of men stratified according to change in body mass index (BMI) (i.e., BMI stable (+/-0.69 kg/m(2)), decreased (-0.7 kg/m(2)), increased minimally (0.7-1.74 kg/m(2)), increased moderately (1.75-3.19 kg/m(2)) and increased most (> or =3.20 kg/m(2))). Eight-year longitudinal cohort study. Four hundred and seventy-four black and 695 white men, aged 24-31 years at the time of the first hormone measurement. Aging-related changes in serum SHBG, total testosterone and bioavailable testosterone. SHBG significantly increased with age for men whose BMI decreased, and there were progressively smaller increases for men whose BMI was stable, or whose BMI increased minimally or moderately (range 1.1-0.3 nM per year, P< or =0.03, respectively). There was no age relationship with SHBG among men whose BMI increased most. Total testosterone did not change with age for men whose BMI decreased, was stable or increased minimally, but for men whose BMI increased moderately and most there was a graded decrease in total testosterone with age (beta=-0.2 and -0.4 nM per year, respectively, P< or =0.005). However, bioavailable testosterone decreased with age to a similar extent across all groups. These results suggest that changes in BMI during young adulthood modulate age-related changes in SHBG and total testosterone, but not bioavailable testosterone.
    International Journal of Obesity 04/2007; 31(4):685-91. · 5.22 Impact Factor
  • ACC Current Journal Review 10/2004; 13(10):16–17.
  • ACC Current Journal Review 02/2004; 13(2):20–21.
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    ABSTRACT: Extensive evidence exists that an inverse relation between education and blood pressure prevails in many adult populations, but little research has been carried out on reasons for this finding. A prior goal of the INTERMAP Study was to investigate this phenomenon further, and to assess the role of dietary factors in accounting for it. Of the 4680 men and women aged 40-59 years, from 17 diverse population samples in Japan, People's Republic of China, UK, and USA, a strong significant inverse education-BP relation was manifest particularly for the 2195 USA participants, independent of ethnicity. With participants stratified by years of education, and assessment of 100+ dietary variables from four 24-h dietary recalls and two 24-h urine collections/person, graded relationships were found between education and intake of many macro- and micronutrients, electrolytes, fibre, and body mass index (BMI). In multiple linear regression analyses with systolic BP (SBP) and diastolic BP (DBP) of individuals the dependent variables (controlled for ethnicity, other possible nondietary confounders), BMI markedly reduced size of education-BP relations, more so for women than for men. Several nutrients considered singly further decreased size of this association by > or =10%: urinary 24-h Na and K excretion, Keys dietary lipid score, vegetable protein, fibre, vitamins C and B6, thiamin, riboflavin, folate, calcium, magnesium, and iron. Combinations of these dietary variables and BMI attenuated the education-SBP inverse coefficient by 54-58%, and the education-DBP inverse coefficient by 59-67%, with over half these effects attributable to specific nutrients (independent of BMI). As a result, the inverse education-BP coefficients ceased to be statistically significant. Multiple specific dietary factors together with body mass largely account for the more adverse BP levels of less educated than more educated Americans. Special efforts to improve eating patterns of less educated strata can contribute importantly to overcoming this and related health disparities in the population.
    Journal of Human Hypertension 10/2003; 17(9):655-775. · 2.82 Impact Factor
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    ABSTRACT: Blood pressure (BP) above optimal (< or =120/< or =80 mmHg) is established as a major cardiovascular disease (CVD) risk factor. Prevalence of adverse BP is high in most adult populations; until recently research has been sparse on reasons for this. Since the 1980s, epidemiologic studies confirmed that salt, alcohol intake, and body mass relate directly to BP; dietary potassium, inversely. Several other nutrients also probably influence BP. The DASH feeding trials demonstrated that with the multiple modifications in the DASH combination diet, SBP/DBP (SBP: systolic blood pressure, DBP: diastolic blood pressure) was sizably reduced, independent of calorie balance, alcohol intake, and BP reduction with decreased dietary salt. A key challenge for research is to elucidate specific nutrients accounting for this effect. The general aim of the study was to clarify influences of multiple nutrients on SBP/DBP of individuals over and above effects of Na, K, alcohol, and body mass. Specific aims were, in a cross-sectional epidemiologic study of 4680 men and women aged 40-59 years from 17 diverse population samples in China, Japan, UK, and USA, test 10 prior hypotheses on relations of macronutrients to SBP/DBP and on role of dietary factors in inverse associations of education with BP; test four related subgroup hypotheses; explore associations with SBP/DBP of multiple other nutrients, urinary metabolites, and foods. For these purposes, for all 4680 participants, with standardized high-quality methods, assess individual intake of 76 nutrients from four 24-h dietary recalls/person; measure in two timed 24-h urine collections/person 24-h excretion of Na, K, Ca, Mg, creatinine, amino acids; microalbuminuria; multiple nutrients and metabolites by nuclear magnetic resonance and high-pressure liquid chromatography. Based on eight SBP/DBP measurements/person, and data on multiple possible confounders, utilize mainly multiple linear regression and quantile analyses to test prior hypotheses and explore relations of multiple dietary and urinary variables to SBP/DBP of individuals. The 4680 INTERMAP participants are equally divided across four age/gender strata: diverse in ethnicity, education, occupation, physical activity; use of cigarettes, alcohol; diagnosed high BP, CVD, diabetes; CVD family history; women vary in parity, use of contraceptive medication and hormone replacement therapy.
    Journal of Human Hypertension 10/2003; 17(9):591-608. · 2.82 Impact Factor
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    ABSTRACT: To examine associations of changes in dietary intake with education in young black and white men and women. The Coronary Artery Risk Development in Young Adults (CARDIA) study, a multi-centre population-based prospective study. Dietary intake data at baseline and year 7 were obtained from an extensive nutritionist-administered diet history questionnaire with 700 items developed for CARDIA. Participants were recruited in 1985-1986 from four sites: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California. Participants were from a general community sample of 703 black men (BM), 1006 black women (BW), 963 white men (WM) and 1054 white women (WW) who were aged 18-30 years at baseline. Analyses here include data for baseline (1985-1986) and year 7 (1992-1993). Most changes in dietary intake were observed among those with high education (>or=12 years) at both examinations. There was a significant decrease in intake of energy from saturated fat and cholesterol and a significant increase in energy from starch for each race-gender group (P<0.001). Regardless of education, taste was considered an important influence on food choice. The inverse relationship of education with changes in saturated fat and cholesterol intakes suggests that national public health campaigns may have a greater impact among those with more education.
    Public Health Nutrition 10/2003; 6(7):689-95. · 2.25 Impact Factor
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    ABSTRACT: To study possible synergistic effects of oats and soy on reducing total and low-density lipoprotein cholesterol (LDL-C) concentrations in human beings and the efficacy and feasibility of including these adjustments to a National Cholesterol Education Program Step I diet. SUBJECT/SETTING: One hundred twenty-seven postmenopausal women with moderate hypercholesterolemia were recruited from a large Midwestern workforce and senior centers in the surrounding community. Intervention and clinical visits were conducted in these same facilities. After a 3-week lead-in period on the Step I diet, participants were randomly assigned to 1 of 4 dietary treatments for an additional 6 weeks: an oats/milk group, a wheat/soy group, an oats/soy group, and a wheat/milk group. Clinical measurements included blood draws, body weight and height, blood pressure, and medical history data. Three-day food records were collected at baseline and Weeks 3 and 9 of the intervention. Randomization was stratified based on the status of hormone replacement therapy and was blocked with sizes 4 or 8 for group assignment. After 3 weeks on the Step I diet, total cholesterol, LDL-C, and triglyceride levels; total fat and saturated fat intake, dietary cholesterol intake, Keys score, and body mass index were all reduced. Following an additional 6 weeks on the Step I diet plus intervention, total cholesterol and LDL-C were further reduced for both the oats/soy group and oats/milk group. There were no significant further changes in total cholesterol, LDL-C, or high-density lipoprotein cholesterol levels in the wheat/soy and wheat/milk groups. Body mass index remained stable in all groups from Week 3 to Week 9. Nonpharmacologic dietary interventions like the Step I diet are feasible in a community setting and can produce rapid and significant lipid-lowering benefits. Daily consumption of 2 servings of oats can contribute to further lipid alterations in this population although soy intake at this dose may not. Palatability and convenience are important considerations in achieving dietary adherence.
    Journal of the American Dietetic Association 12/2001; 101(11):1319-25. · 3.80 Impact Factor
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    ABSTRACT: The objective of this study was to determine whether lower extremity peripheral arterial disease (PAD) is associated with depressive symptoms and whether PAD-related disability mediates the association between PAD and depressive symptoms. The study used a cross-sectional design set in an academic medical center. A cohort of men and women aged 55 years and older with (n = 93) or without (n = 74) PAD was recruited. PAD subjects were identified from a blood flow laboratory and a general medicine practice. Non-PAD subjects were identified from the same general medicine practice. PAD was diagnosed and quantified using the ankle-brachial index (ABI). Depressive symptoms were assessed by the 15-item short version of the Geriatric Depression Scale (GDS-S; score range 0-15, 0 = no depressive symptoms). The six-minute walk test and the Walking Impairment Questionnaire (WIQ) distance score (score range 0-100, 100 = better walking ability) were measures of walking impairment. PAD subjects had depressive mood (DM) (defined by GDS-S score >5) twice as often as controls (24% vs 12%, p = 0.06). After adjustment for age, education, and number of comorbidities, the prevalence of depressive mood among PAD subjects was increased, but this association was not significant (OR = 1.8, 95% CI 0.7-4.4). The WIQ distance score weakened the association between PAD and DM, and higher distance scores were associated with a lower likelihood of DM (OR = 0.98 per one unit of the WIQ, 95% CI 0.96-0.99). Among PAD subjects, severe PAD (ABI <0.5) was not significantly associated with DM (OR = 1.4, 95% CI 0.5-4.1), but a greater 6-min walk distance was associated with a lower likelihood of DM (OR = 0.8 per 100 feet, 95% CI 0.70-0.97). Substituting the WIQ scores for six-min walk distance in the model showed that higher WIQ scores were associated with lower likelihood of DM among PAD subjects (OR= 0.98 per one unit of the WIQ, 95% CI 0.95-1.0), though the association did not achieve statistical significance. In conclusion, these data suggest that PAD may be associated with an increased risk of DM and that this relationship may be related to PAD-associated disability. An evaluation for depression may be appropriate in men and women with PAD. Findings should be evaluated in a larger study cohort.
    Vascular Medicine 11/2001; 6(4):229-34. · 1.62 Impact Factor
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    ABSTRACT: Persons with lower-extremity peripheral arterial disease (PAD) are often asymptomatic or have leg symptoms other than intermittent claudication (IC). To identify clinical characteristics and functional limitations associated with a broad range of leg symptoms identified among patients with PAD. Cross-sectional study of 460 men and women with PAD and 130 without PAD, who were identified consecutively, conducted between October 1998 and January 2000 at 3 Chicago-area medical centers. Ankle-brachial index score of less than 0.90; scores from 6-minute walk, accelerometer-measured physical activity over 7 days, repeated chair raises, standing balance (full tandem stand), 4-m walking velocity, San Diego claudication questionnaire, Geriatric Depression Score Short-Form, and the Walking Impairment Questionnaire. All groups with PAD had poorer functioning than participants without PAD. The following values are for patients without IC vs those with IC. Participants in the group with leg pain on exertion and rest (n = 88) had a higher (poorer) score for neuropathy (5.6 vs 3.5; P<.001), prevalence of diabetes mellitus (48.9% vs 26.7%; P<.001), and spinal stenosis (20.8% vs 7.2%; P =.002). The atypical exertional leg pain/carry on group (exertional leg pain other than IC associated with walking through leg pain [n = 41]) and the atypical exertional leg pain/stop group (exertional leg pain other than IC that causes one to stop walking [n = 90]) had better functioning than the IC group. The group without exertional leg pain/inactive (no exertional leg pain in individual who walks </=6 blocks per week [n = 28]) and the leg pain on exertion and rest group had poorer functioning than those with IC. Adjusting for age, sex, race, and comorbidities and compared with IC, participants with atypical exertional leg pain/carry on achieved a greater distance on the 6-minute walk (404.3 vs 328.5 m; P<.001) and were less likely to stop during the 6-minute walk (6.8% vs 36%; P =.002). The group with pain on exertion and rest had a slower time for completing 5 chair raises (13.5 vs 11.9 seconds; P =.009), completed the tandem stand less frequently (37.5% vs 60.0%; P =.004), and had a slower 4-m walking velocity (0.80 vs 0.90 m/s; P<.001). There is a wide range of leg symptoms in persons with PAD beyond that of classic IC. Comorbid disease may contribute to these symptoms in PAD. Functional impairments are found in every PAD symptom group, and the degree of functional limitation varies depending on the type of leg symptom.
    JAMA The Journal of the American Medical Association 10/2001; 286(13):1599-606. · 29.98 Impact Factor
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    ABSTRACT: Data are limited on blood pressure (BP) in young adults and long-term mortality. Moreover, screening and hypertension treatment guidelines have been based mainly on findings for middle-aged and older populations. This study assesses relationships of BP measured in young adult men to long-term mortality due to coronary heart disease (CHD), cardiovascular diseases (CVD), and all causes. This cohort from the Chicago Heart Association Detection Project in Industry included 10 874 men aged 18 to 39 years at baseline (1967-1973), not receiving antihypertensive drugs, and without CHD or diabetes. Relationship of baseline BP to 25-year CHD, CVD, and all-cause mortality was assessed. Age-adjusted association of systolic BP to CHD mortality was continuous and graded. Multivariate-adjusted CHD hazard ratios (HRs) for 1 SD higher systolic BP (15 mm Hg) and diastolic BP (10 mm Hg) were 1.26 (95% confidence interval [CI], 1.11-1.44) and 1.17 (95% CI, 1.01-1.35), respectively. Compared with the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure stratum with normal BP (and lowest mortality rates), the large strata with high-normal BP and stage 1 hypertension had 25-year absolute risks for death of 63 and 72 per 1000, respectively, and absolute excess risks of 10 and 20 per 1000, respectively; accounted for 59.8% of all excess CHD, CVD, and all-cause mortality; and were estimated to have life expectancy shortened by 2.2 and 4.1 years, respectively. In young adult men, BP above normal was significantly related to increased long-term mortality due to CHD, CVD, and all causes. Population-wide primary prevention, early detection, and control of higher BP are indicated from young adulthood on.
    Archives of Internal Medicine 07/2001; 161(12):1501-8. · 11.46 Impact Factor

Publication Stats

5k Citations
816.42 Total Impact Points


  • 1983–2012
    • Northwestern University
      • • Department of Preventive Medicine
      • • Department of Medicine
      • • Center for Community Health
      Evanston, Illinois, United States
  • 2011
    • Oakland University
      • Department of Psychology
      Rochester, MI, United States
  • 2001
    • Columbia University
      • JP Sulzberger Columbia Genome Center
      New York City, NY, United States
  • 2000
    • National Human Genome Research Institute
      Maryland, United States
  • 1999
    • Wayne State University
      Detroit, Michigan, United States
  • 1995–1996
    • University of Minnesota Twin Cities
      • School of Public Health
      Minneapolis, MN, United States
  • 1994
    • University of Illinois at Chicago
      Chicago, Illinois, United States
  • 1992
    • University of Utah
      • Department of Family and Preventive Medicine
      Salt Lake City, UT, United States