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Bruce D Johnson

Publications and source records attributed to Bruce D Johnson.

At least 37 records · Page 2Linked to original sources
PubMed2006

Influence of beta2-adrenergic receptor genotype on airway function during exercise in healthy adults.

BACKGROUND: In humans, beta(2)-adrenergic receptors (beta(2)ARs) influence airway tone. There are known functional polymorphisms of the beta(2)AR, such as substitution of glycine for arginine at codon 16. We sought to determine if this variation in genotype differentially influences airway function during exercise. METHODS: Healthy subjects without asthma who were either homozygous for Arg16 (n = 16; mean age, 29 +/- 2 years [+/- SD]; mean maximum oxygen uptake [Vo(2)], 32 +/- 2 mL/kg/min) or the Gly16 allele (n = 26; mean age, 30 +/- 1 years; mean maximum Vo(2), 33 +/- 1 mL/kg/min) participated in the study. Baseline testing included spirometry and maximal symptom-limited exercise. On a separate day, an arterial cannula was placed to measure catecholamine levels. Subjects then performed exercise at two work levels (40% and 75% of peak work) for 9 min each and performed spirometry at 3-min intervals for assessment of airway function. RESULTS: There were no statistically significant differences between groups in maximum Vo(2) or baseline spirometry (p > 0.05). With both light and heavy exercise, the groups had similar increases in the forced expiratory flow at 50% of vital capacity (FEF(50)). FEF(50) increased by 14 +/- 4% and 15 +/- 3% in arginine and glycine groups, respectively, by end exercise (p > 0.05). During recovery (5 min and 10 min after), the Gly16 homozygotes demonstrated persistent bronchodilation (10 min after FEF(50) = + 7 +/- 2% over pre-exercise) while the Arg16 subjects had a rapid return to baseline (10 min after FEF(50) = - 3 +/- 3%, p = 0.007 between groups). No differences were observed in the catecholamine responses between genotypes, although the increase in epinephrine in the arginine group tended to be higher (p = 0.07). CONCLUSIONS: These data suggest that the Arg16Gly polymorphism of the beta(2)AR does not influence airway function during short-duration low- and high-intensity exercise. However, during recovery, the Arg16 genotype is associated with a reduced bronchodilation, possibly due to increased catecholamine desensitization.

Adult↗
PubMed2006

Competition for intrathoracic space reduces lung capacity in patients with chronic heart failure: a radiographic study.

BACKGROUND: The purpose of this study was to determine the influence of changes in cardiac size on total lung volume in patients with chronic heart failure compared to control subjects. METHODS: Forty-four patients and age-, gender-, and height-matched control participants were recruited. All participants underwent posteroanterior and lateral chest radiography for volumetric estimations of the total thoracic cavity (TTC), diaphragm, heart, and lungs. To assess the relationship between chronic heart failure severity and cardiac enlargement, patients with chronic heart failure were classified into groups based on New York Heart Association class, as follows: class I and II, n = 26 (group A); class III and IV, n = 18 (group B). RESULTS: There was no difference between the groups for TTC volume (TTCV) [p = 0.56]. Cardiac volumes were significantly different between all groups for both the absolute volumes (p < 0.001) were calculated as a percentage of TTCV (p < 0.001), with the largest cardiac volumes in group B (twice the volume of healthy control subjects). When expressed as a percentage of TTCV, there also was a clear reduction in lung volumes as a function of disease severity (p < 0.001). CONCLUSIONS: The present study demonstrates a close relationship between the severity of heart failure and cardiac size. These changes in cardiac size within a closed thoracic cavity may pose significant constraints on the lungs, resulting in reductions in lung volumes that likely play a major role in the restrictive breathing patterns often reported in patients with chronic heart failure.

Cardiomegaly↗
PubMed2006

Beta2-adrenergic receptor genotype and pulmonary function in patients with heart failure.

OBJECTIVE: Chronic heart failure (CHF) is associated with neurohumoral activation and decrements in pulmonary function (PF). The beta2-adrenergic receptor (ADRB2) modulates airway smooth muscle tone and influences lung fluid clearance. Common polymorphisms of the ADRB2 are associated with differences in ADRB2 function and therefore could differentially influence PF in patients with CHF. METHODS: We studied baseline PF according to genetic variations of the ADRB2 at amino acid 16 (ie, arginine [Arg] or glycine [Gly]) in 126 CHF patients (mean [+/- SEM] age, 56 +/- 1 years; left ventricular ejection fraction [LVEF], 29 +/- 1%; body mass index [BMI], 28 +/- 0.4 kg/m2) and in 100 healthy control subjects (mean age, 50 +/- 2 years; LVEF, 63 +/- 0.7%; BMI, 25 +/- 0.3 kg/m2). RESULTS: Venous epinephrine levels did not differ between CHF patients and control subjects or across genotype groups; however, norepinephrine levels were higher in CHF patients and was greater in ArgArg patients compared to GlyGly patients (p < 0.05). PF did not differ according to genotype in control subjects; however, CHF patients who were homozygous for Arg had reduced PF relative to heterozygotes or those subjects who were homozygous for Gly (vital capacity: ArgArg group, 82 +/- 3% predicted; ArgGly group, 92 +/- 2% predicted; GlyGly group, 93 +/- 2% predicted; FVC: ArgArg group, 77 +/- 3% predicted; ArgGly group, 89 +/- 2% predicted; GlyGly group, 90 +/- 2% predicted; FEV1: ArgArg group, 75 +/- 4% predicted; ArgGly group, 86 +/- 3% predicted; GlyGly group, 87 +/- 2% predicted; diffusing capacity of the lung for carbon monoxide: ArgArg group, 76 +/- 4% predicted; ArgGly group, 83 +/- 2% predicted; GlyGly group, 85 +/- 2% predicted; p < 0.05). In addition, there was a modest correlation between mitral valve inflow deceleration time and PF in CHF patients (r = 0.42; p < 0.01), but not in control subjects. CONCLUSIONS: These data suggest that genetic variation of the ADRB2 is associated with differences in PF in CHF patients but not in healthy subjects, which may be related to an increased susceptibility of the homozygous Arg subjects to agonist-mediated desensitization of ADRB2s in the lungs, or related to an influence of this polymorphism on cardiac diastolic properties.

Adult↗
PubMed2006

Correspondence between the adult treatment panel III criteria for metabolic syndrome and insulin resistance.

OBJECTIVE: The aim of the present study was to assess the diagnostic accuracy of the Adult Treatment Panel III (ATP-III) definition of the metabolic syndrome in identifying insulin-resistant individuals and to explore alternative approaches to improve identification of insulin-resistant individuals among asymptomatic adults from the general population. RESEARCH DESIGN AND METHODS: The sample consisted of 256 non-Hispanic white subjects without treated hypertension or diabetes, from the Rochester (Minnesota) Heart Family Study (123 men and 133 women; aged 20-60 years). Frequently sampled intravenous glucose tolerance tests were performed in all subjects. The reference standard for insulin resistance was determined by Bergman's minimal model; insulin resistance was defined as an insulin sensitivity index <2 x 10 min(-1) . microU(-1) . ml(-1). Component metabolic syndrome measures included blood pressure determined by sphygmomanometer; fasting serum triglycerides, HDL cholesterol, and glucose concentrations determined enzymatically; and waist circumference determined by tape measure. RESULTS: By ATP-III criteria, the prevalence of metabolic syndrome was 15.6% (16.3% in men and 15.1% in women; P = 0.465). The presence of metabolic syndrome had low sensitivity to identify insulin resistance (45% in men and 39% in women; sex difference, P = 0.137) but high specificity (93% in men and 95% in women; sex difference, P = 0.345). Based on the area under the receiver operating characteristic curve (AUC) constructed by counting metabolic syndrome components as recommended by ATP-III, diagnostic accuracy was fair (AUC = 0.797 in men and 0.747 in women). When component metabolic syndrome measures were considered as quantitative traits rather than dichotomized, use of waist circumference alone, rather than counting metabolic syndrome components, improved diagnostic accuracy for insulin resistance (in men, AUC = 0.906, P = 0.001; in women, AUC = 0.822, P = 0.10). CONCLUSIONS: Application of the ATP-III metabolic syndrome criteria provides good specificity but low sensitivity to screen asymptomatic white adults for insulin resistance. Measuring just waist circumference is simpler and may provide greater accuracy for identifying insulin resistance.

Adult↗
PubMed2005

Arg16Gly polymorphism of the beta2-adrenergic receptor is associated with differences in cardiovascular function at rest and during exercise in humans.

In humans, subjects homozygous for arginine (ArgArg) at codon 16 of the beta2-adrenergic receptor (beta2AR) have been shown to have greater agonist-mediated desensitization than subjects homozygous for glycine (GlyGly). We sought to determine if this substitution differentially influenced cardiovascular function during short duration (9 min) low and high intensity exercise (40 and 75% of peak work). Healthy Caucasian ArgArg (n = 16), GlyGly (n = 31) and ArgGly (n = 17) subjects matched for age, sex and peak oxygen uptake were studied. There were no differences in adrenaline (ADR) at rest or with heavy exercise, but the ArgArg group had lower ADR with light exercise (P = 0.04). Resting heart rate (HR) was higher in ArgArg (P < 0.01), while cardiac output (Q), stroke volume (SV), and mean arterial pressure (MAP) were lower than the other groups (HR = 86+/-2, 78+/-2, 80+/-1 beats min(-1); Q = 5.7+/-0.81, 6.1+/-0.18, 6.7+/-0.22 l min(-1); SV = 68+/-3, 82+/-3, 89+/-4 ml beat(-1); MAP = 92+/-1, 103+/-2, 98+/-1 mmHg-- for ArgArg, ArgGly and GlyGly, respectively, means +/-s.e.m., P < 0.01), however, no differences were observed in systemic vascular resistance (SVR). With low intensity exercise and high intensity exercise the ArgArg group continued to have a lower , SV and MAP compared to the other groups (P < 0.05), with no differences observed in SVR. During recovery, the ArgArg subjects continued to have a lower MAP but there were no differences in HR, , or SVR. These data suggest that subjects homozygous for Arg at codon 16 of the beta2AR have reduced and MAP at rest that persist during exercise with no evidence for differential changes over the course of exercise despite large changes in catecholamines. This may suggest possible genotype-related differences in baseline receptor function or density which causes phenotypic differences at rest that are sustained during short-term exercise.

Adult↗
PubMed2005

Evaluation of cardiac output from a tidally ventilated homogeneous lung model.

We used the direct Fick measurements to validate a method for estimating cardiac output by iteratively fitting VCO(2) at the mouth to lung model values. This model was run using a series of 50, 30 and 10 breaths to test sensitivity to number of breaths used for fitting. The lung was treated as a catenary two-compartment lung model consisting of a dead space compartment connected with a single alveolar space compartment, perfused with constant pulmonary blood flow. The implemented mathematical modeling described variations in O(2) and CO(2) compartmental fractions and alveolar volume. This model also included pulmonary capillary gas exchange. Experimental data were collected from measurements performed on six healthy subjects at rest and during 20, 40, 60 and 85-90% of peak V(O)(2). The correlation between the two methods was highest and the average agreement between the methods was best using 50 breaths R = 095; P < 0.0001; Q(model) = 1.1Q(Fick) - 2.3). The mean difference and lower to upper limits of agreement between measured and estimated data were 0.7 l/min (-2.7 to 4.1 l/min) for cardiac output; -0.9 ml/100 ml (-1.3 to -0.5 ml/100 ml) for arterial O(2) content; -0.8 ml/100 ml (-3.8 to 2.2 ml/100 ml) for mixed venous O(2) content and -0.1 ml/100 ml (-2.9 to 2.7 ml/100 ml) for arteriovenous difference O(2) content. The cardiac output estimated by the lung model was in good agreement with the direct Fick measurements in young healthy subjects.

Adult↗
PubMed2005

An open-circuit method for determining lung diffusing capacity during exercise: comparison to rebreathe.

To avoid limitations associated with the use of single-breath and rebreathe methods for assessing the lung diffusing capacity for carbon monoxide (D(L)CO) during exercise, we developed an open-circuit technique. This method does not require rebreathing or alterations in breathing pattern and can be performed with little cognition on the part of the patient. To determine how this technique compared with the traditional rebreathe (D(L)CO,RB) method, we performed both the open-circuit (D(L)CO,OC) and the D(L)CO,RB methods at rest and during exercise (25, 50, and 75% of peak work) in 11 healthy subjects [mean age = 34 yr (SD 11)]. Both D(L)CO,OC and D(L)CO,RB increased linearly with cardiac output and external work. There was a good correlation between D(L)CO,OC and D(L)CO,RB for rest and exercise (mean of individual r2 = 0.88, overall r2 = 0.69, slope = 0.97). D(L)CO,OC and D(L)CO,RB were similar at rest and during exercise [e.g., rest = 27.2 (SD 5.8) vs. 29.3 (SD 5.2), and 75% peak work = 44.0 (SD 7.0) vs. 41.2 ml.min(-1).mmHg(-1) (SD 6.7) for D(L)CO,OC vs. D(L)CO,RB]. The coefficient of variation for repeat measurements of D(L)CO,OC was 7.9% at rest and averaged 3.9% during exercise. These data suggest that the D(L)CO,OC method is a reproducible, well-tolerated alternative for determining D(L)CO, particularly during exercise. The method is linearly associated with cardiac output, suggesting increased alveolar-capillary recruitment, and values were similar to the traditional rebreathe method.

Adult↗
PubMed2005

Gender differences in the distribution of cocaine and heroin in Central Harlem.

OBJECTIVE: This article investigates the extent to which users of crack, powder cocaine and heroin in Central Harlem participate in various roles involved in distributing these drugs, examining gender differences among distribution roles. METHODS: Several strategies were combined to acquire a sample of 655 hard drug users and sellers who self-reported demographics, drug use and other factors in a face-to-face interview. Chi-square analyses were used to examine factors associated with having drug distribution roles. RESULTS: More than two-fifths (N = 269) of all respondents self-reported participation in at least one current distribution role. The most common roles were acting as a middleman, steering buyers, holding drugs or money, and transporting drugs. Distributors were more likely to have HIV, previous drug treatments, and less education, employment or housing, but had higher incomes than users. A higher proportion of women reported drug distribution roles, but among distributors, men were twice as likely women to be direct sellers and transporters of drugs, and to perform more distribution roles. CONCLUSIONS: Gender contrasts support previous research indicating male dominance of drug distribution roles. Previous studies may underestimate women's participation in distribution roles. Drug treatment programs are encouraged to augment existing relapse prevention activities with distribution prevention efforts.

Adult↗
PubMed2005

Effects of beta-blocker therapy on ventilatory responses to exercise in patients with heart failure.

BACKGROUND: Ventilatory efficiency is the increase in ventilation relative to carbon dioxide production during exercise. Congestive heart failure (CHF) is associated with decreased ventilatory efficiency. beta-blockers improve hemodynamics, prolong survival, and improve functional class in patients with CHF, though peak exercise performance may not improve. We hypothesized beta-blockers increase ventilatory efficiency in patients with CHF. METHODS AND RESULTS: The study group comprised 614 subjects with left ventricular ejection fraction < or = 40% referred for cardiopulmonary exercise testing. Clinical and exercise data were reviewed and recorded. For comparison, subjects were divided into those treated with beta-blockers (n = 195) and those not treated (n = 419). Subjects on beta-blockers had lower minute ventilation (12 +/- 4 versus 14 +/- 4 L/min, P < .001) at rest, which remained lower during submaximal and maximal exercise, by 4 and 6 L/min, respectively (P = .001). Ventilatory efficiency was increased in subjects treated with beta-blockers at submaximal (32 +/- 6 versus 34 +/- 7, P = .002) and maximal (34 +/- 7 versus 37 +/- 10, P = .005) exercise. Differences between treatment subgroups remained significant by covariate analysis; beta-blockers were also independently associated with decreased minute ventilation by multiple regression. CONCLUSION: Beta-blockers may be associated with increased ventilatory efficiency in CHF patients, which may contribute to improved functional class and quality of life.

Adrenergic beta-Antagonists↗
PubMed2005

Left atrial index is a predictor of exercise capacity in patients with hypertrophic cardiomyopathy.

BACKGROUND: Left atrial (LA) enlargement is related to diastolic dysfunction and mitral regurgitation (MR), both of which are common in patients with hypertrophic cardiomyopathy (HCM). This study investigates the association between LA size and exercise capacity in patients with HCM. METHODS: All HCM patients who underwent a treadmill test with direct measurement of oxygen consumption (VO2) and a standard transthoracic echocardiography within 30 days in the years 2001-2003 were identified. Patients with significant comorbidities were excluded. Exercise capacity was defined as percentage of predicted peak VO2. Clinical and echocardiographic parameters were compared with those of a group of normal subjects. RESULTS: Compared with normal subjects, HCM patients had increased left atrial (LA) volume index (36 vs 21 mL/m2; P < .0001) and mitral E/e' ratio (14 vs 9; P < .0001); 27% of the patients had at least moderate MR. LA volume index demonstrated borderline correlation with exercise capacity (r = -.20; P = .06) but was an independent predictor of exercise capacity in a multivariate linear analysis, together with body mass index, heart rate at rest, and left ventricular end-systolic diameter. Including the parameters E/e' ratio or moderate or severe MR did not add incremental value to the model. CONCLUSION: LA volume index, reflecting the combined influences of MR and diastolic dysfunction, was independently associated with objective measures of exercise capacity in patients with isolated HCM.

Cardiomyopathy, Hypertrophic↗
PubMed2005

Blood pressure variation in healthy humans: a possible interaction with beta-2 adrenergic receptor genotype and renal epithelial sodium channels.

Renal control of Na(+) regulation is a critical component to blood pressure regulation. It has recently been suggested that the beta-2 adrenergic receptor plays a role in blood pressure regulation possibly via renal epithelial sodium channels (ENaC). In the kidneys, gain of function mutations of the ENaC leads to increased salt-sensitivity and hypertension (Liddle's syndrome). In contrast, loss of function mutations of the ENaC leads to pseudohypoaldosteronism and is characterized by hypotension. Polymorphic variation of the beta-2 adrenergic receptor (beta2AR, the Arg16Gly polymorphism) leads to differences in physiologic function, in vivo. Specifically, subjects homozygous for Glycine at amino acid 16 have been shown to have enhanced forearm blood flow in response to isoproterenol and better airway function at baseline and during exercise when compared to subjects homozygous for Arginine at amino acid 16. We hypothesize, therefore, that subjects that are homozygous for Gly at amino acid 16 of the beta2AR have higher baseline blood pressure than Arg16 homozygotes due to beta2AR-mediated increases in ENaC activity in the kidney, caused, at least in part, by greater beta2AR density or enhanced beta2AR function of the Gly16 group.

Adult↗
PubMed2005

The new heroin users among Manhattan arrestees: variations by race/ethnicity and mode of consumption.

The incidence of heroin use among Manhattan arrestees interviewed by the Arrestee Drug Abuse Monitoring (ADAM) program remained around 20% from 1987 through 2001. However, the authors had expected a decline because the heroin injection epidemic peaked back in the 1960s and early 1970s. A detailed analysis found differences across race/ethnicity. Black arrestees born since 1955 (who came of age since the heroin injection epidemic) were much less likely to use heroin than those born between 1945 and 1954 (who came of age during the epidemic). Hispanic arrestees born since 1970 (but not those born between 1955 and 1969) were also less likely to use heroin, suggesting that the decline in heroin use started among Blacks before Hispanics. During the 1990s, sniffing replaced injecting as the predominant mode of heroin consumption for Black and Hispanic arrestees, even among older arrestees. In strong contrast, the prevalence of heroin use among White arrestees did not decline in the 1990s and injection was still their most popular method of consumption. The discussion highlights implications for further research and drug treatment.

Adult↗
PubMed2005

The growth in marijuana use among American youths during the 1990s and the extent of blunt smoking.

Marijuana use among American youths and young adults increased substantially during the 1990s. This paper reviews that trend using data collected 1979-2003 by the National Survey on Drug Use and Health (NSDUH). The data suggest that the increase in marijuana use started first among persons age 12-20. Among 18-20 year-olds, the increase started earlier among whites and blacks than Hispanics, among males before females, and surprisingly in areas that are not part of an MSA as opposed to those with a population in excess of a million. Much of the increase in marijuana use could have been attributable to the growing popularity of blunts. Starting in 2000, the NSDUH explicitly asked youths age 12-17 (but not older respondents) about smoking blunts. Of the 9% of youths who reported past-30-day use of marijuana 2000-03, more than half reported smoking blunts. On the other hand, the data also indicate that blunts have not fully supplanted other ways that youths consume marijuana. Blunts were more common among youths that were black, older, male, and from metropolitan areas. Many blunt smokers reported they had not used marijuana, which suggests that they did not define smoking blunts as marijuana use. Even fewer reported that they had used cigars, suggesting they did not define smoking blunts as cigar use.

Adolescent↗
PubMed2005

Cigars-for-blunts: choice of tobacco products by blunt smokers.

An important part of blunt (marijuana in a cigar shell) smoking is the ritual of the preparation process and the selection of tobacco product for the blunt. This article explores reasons for selection from the different tobacco products available in the legal commercial market. Based upon three years of ethnographic research with 92 focal subjects, the analysis focuses upon the practical, subcultural, and symbolic reasons that blunt smokers give for choosing tobacco products (cigars for blunts-CFBs) employed in the blunt preparation process. The blunt ritual also functions within the marijuana subculture to differentiate blunt smokers from joints/pipes smokers. This analysis explores the reasons users give for selecting among the most popular inexpensive cigar brands (Dutch Masters, Phillies Blunts, and Backwoods) all owned and marketed by a single cigar conglomerate. Blunt chasing--the smoking of a cigarillo or cigar following a blunt--is an emergent phenomenon that further expands the market for tobacco products among blunt smokers. Recently, many different flavors have been added to these tobacco products in order to attract young and minority blunt consumers.

Adolescent↗
PubMed2005

Sessions, cyphers, and parties: settings for informal social controls of blunt smoking.

The importance of settings for marijuana use has been widely noted, but the way that informal social controls are organized to moderate the amounts consumed have not been well documented. A major ethnographic study of blunts/marijuana use in New York City observed several hundred marijuana users in group locations and conducted intensive interviews with 92 focal subjects. The vast majority of blunt smokers preferred to consume in a group setting. Participants identified three group settings in which blunt smoking often occurred-sessions, cyphers, and parties. The analysis identifies various conduct norms, rituals, and behavior patterns associated with each of these settings. Regardless of the setting, group processes encouraged equal sharing of blunts, moderation in consumption, intermission and breaks between smoking episodes, and involvement in non-smoking activities. Blunt smoking groups rarely encouraged high consumption and intoxication from marijuana.

Adolescent↗
PubMed2004

How much do Manhattan-arrestees spend on drugs?

INTRODUCTION: Information about individuals' drug expenses can indicate much about the size of drug markets, the financial burden of use, drug-related crime, and potential challenges for treatment. Most often, expenses have been estimated holistically by asking respondents to report how much they spent. In 2000, the Arrestee Drug Abuse Monitoring (ADAM) program introduced an advanced questionnaire using a series of highly specific questions like, "how much cash did you pay for crack that last time you bought it?" METHODS: This paper describes a procedure for estimating arrestees' drug expenses with the new ADAM questionnaire, discusses pitfalls in interpretation, presents findings for 2979 ADAM-Manhattan respondents interviewed 2000-2002, examines covariates of drug expense, and compares the 2000-2002 findings with those obtained from 2256 respondents interviewed 1998-1999 with the previous questionnaire. RESULTS: Among 2000-2002 arrestees, median drug expense in the past 30 days varied widely with frequency of use and drug-user type. Infrequent marijuana-only users spent as little as $5, daily marijuana-only users spent about $600. Arrestees that used both heroin and cocaine spent over $1000. Estimates with the 1998-1999 data were about half as large. DISCUSSION: ADAM's new drug market questions may greatly advance the quality of estimates of drug expenses. However, further research is needed to better establish the estimator's accuracy.

Adult↗
PubMed2004

Plasma leptin and prognosis in patients with established coronary atherosclerosis.

OBJECTIVES: This study was designed to evaluate the relationship between plasma leptin and prognosis in patients with angiographically confirmed coronary atherosclerosis. BACKGROUND: Experimental studies suggest that leptin, an adipose tissue-derived hormone, exerts important cardiovascular effects. METHODS: Study subjects were recruited prospectively from a cohort of patients undergoing clinically indicated coronary angiography (n = 382). The median duration of follow-up was four years. Follow-up information was available for 361 patients. RESULTS: The combined end point of cardiac death, myocardial infarction (MI), cerebrovascular accident, or re-vascularization occurred in 44 subjects. In the simple Cox model, leptin had a significant (p < 0.001) non-linear/cubic univariate relationship with the combined end point. Other variables associated with prognosis in the univariate analysis were body mass index (BMI), prior MI, insulin resistance, C-reactive protein (CRP), fibrinogen, and number of coronary vessels with >50% stenosis. A positive relationship between leptin and prognosis was also seen when leptin levels were split by quintiles, with a hazard ratio of 6.46 for the highest quintile. The only two variables significantly associated with the combined end point in the multivariate Cox model were leptin (p = 0.004) and number of coronary vessels with >50% stenosis (p < 0.001). A similar relationship between leptin and prognosis was observed when leptin was adjusted for BMI. CONCLUSIONS: In patients with angiographically confirmed coronary atherosclerosis, leptin is a novel predictor of future cardiovascular events independent of other risk factors, including lipid status and CRP.

Aged↗