Doctors' perceptions of the prognostic benefit of statins in patients who have had myocardial infarction

Background: We wished to assess how General Practitioners (GPs) and cardiologists perceive and communicate the benefits of therapy with statins (hydroxymethylglutaryl-coenzyme A reductase inhibitors) in a patient following myocardial infarction.
Methods: We interviewed 20 GPs and 22 cardiologists to determine treatment policy and ways of expressing its benefits to a patient after myocardial infarction with moderate dyslipidaemia. We asked what drug and dosage they would recommend and how they would express potential benefits of therapy, given a range of options including reduced relative and absolute risk of events.
Results: Most GPs would start a low dose (10–20 mg/day) of simvastatin (the only freely prescribable funded statin in New Zealand) whereas cardiologists would commence 40 mg/day immediately ( P  = 0.001). All but one cardiologist would justify therapy to the patient by citing a reduced chance of a major adverse cardiovascular event. Nine GPs and one cardiologist estimated a gain of more than 5 years of life from statin therapy. Cardiologists were more optimistic than GPs about relative risk reduction ( P  = 0.04). Only 50% of GPs and 68% of cardiologists were able to estimate an absolute risk reduction over 5 years, such estimates varying widely with no significant difference in responses between the groups ( P  = 0.2). No doctors felt comfortable using number needed to treat or odds ratio.
Conclusion: There were substantial differences between the two groups of clinicians in perception and policy of statin therapy, frequent overestimation of treatment benefits and a reluctance to impart numerical estimates of benefit to patients.     

Comparison of treadmill scores with physician estimates of diagnosis and prognosis in patients with coronary artery disease

Objective Our purpose was to compare exercise test scores and ST measurements with a physician's estimation of the probability of the presence and severity of angiographic disease and the risk of death. The American College of Cardiology/American Heart Association exercise testing guidelines provide equations to calculate treadmill scores and recommend their use to improve the predictive accuracy of the standard exercise test. However, if physicians can estimate the probability of coronary artery disease and prognosis as well as the scores, there is no reason to add this complexity to test interpretation. Methods A clinical exercise test was performed and an angiographic database was used to print patient summaries and treadmill reports. The clinical/treadmill test reports were sent to expert cardiologists and to 2 other groups, including randomly selected cardiologists and internists. They classified the patients summarized in the reports as having a high, low, or intermediate probability for the presence of any severe angiographic disease and estimated a numerical probability from 0% to 100%. The Social Security Death Index was used to determine survival status of the patients. Results Twenty-six percent of the patients had severe angiographic disease, and the annual mortality rate for the population was 2%. Forty-five expert cardiologists returned estimates on 473 patients, 37 randomly chosen practicing cardiologists returned estimates on 202 patients, 29 randomly chosen practicing internists returned estimates on 162 patients, 13 academic cardiologists returned estimates on 145 patients, and 27 academic internists returned estimates on 272 patients. When probability estimates for presence and severity of angiographic disease were compared, in general, the treadmill scores were superior to physicians' and ST analysis at predicting severe angiographic disease. When prognosis was estimated, treadmill prognostic scores did as well as expert cardiologists and better than most other physician groups. Conclusion Estimates of the presence of clinically significant and severe angiographic coronary artery disease provided by scores were superior to physician estimates and ST analysis alone. Estimates of prognosis provided by scores were similar to the estimates made by expert cardiologists and more accurate than the estimates made by most other physician groups. (Am Heart J 2002;143:650-8.)     

Knowledge and perception of guidelines and secondary prevention of coronary heart disease among general practitioners and internists. Results from a physician survey in Germany.

AIMS: This study investigated knowledge and perception of guidelines in secondary prevention of coronary heart disease and the impact of guideline knowledge on treatment practices in coronary patients among primary care physicians. DESIGN AND METHODS: A representative questionnaire survey was performed in 2002-2003 among all 1023 general practitioners and office-based internists in the Region of Münster, Germany. The survey instrument contained questions on knowledge and attitudes toward guidelines, risk factors and treatment practices in secondary prevention of coronary heart disease. RESULTS: In total, 681 (66.6%) physicians participated. Seventy percent of physicians reported knowledge of at least one guideline. Participants expressed mainly positive attitudes toward guidelines but also reported important barriers to their implementation such as lack of reimbursement. Only 63 and 32%, respectively, reported to start antihypertensive and lipid-lowering treatment according to guidelines. Physicians reporting guideline knowledge were more likely to initiate lipid-lowering treatment of elevated low-density lipoprotein (LDL)-cholesterol [odds ratio (OR) 2.3; 95% confidence interval (CI) 1.5-3.5], to intensively advise overweight patients (OR 1.5; 95% CI 1.0-2.5), to make use of nicotine replacement therapy or cessation courses in smoking patients (OR 1.7; 95% CI 1.2-2.4), and to comply with an overall measure of guideline adherence (OR 1.8; 95% CI 1.1-2.8). CONCLUSIONS: In this study, guideline knowledge led to improved cardiovascular risk factor treatment among GPs and internists. Many physicians, however, do not treat coronary patients according to evidence-based guidelines. Further dissemination of guidelines and educational efforts are essential to improve secondary prevention of coronary heart disease.     

Comparison of exercise test scores and physician estimation in determining disease probability

BACKGROUND: The recent American College of Cardiology/American Heart Association exercise testing guidelines provided equations to calculate treadmill scores and recommended their use to improve the predictive accuracy of the standard exercise test. However, if physicians can estimate the probability of coronary artery disease as well as the scores can, there would be no reason to add this complexity to test interpretation. To compare the exercise test scores with physician's estimation of disease probability, we used clinical, exercise test, and coronary angiographic data to compute the recommended scores and print patient summaries and treadmill reports. OBJECTIVE: To determine whether exercise test scores can be as effective as expert cardiologists in diagnosing coronary disease. METHODS: Five hundred ninety-nine consecutive male patients without previous myocardial infarction with a mean +/- SD age of 59 +/- 11 years were considered for this analysis. With angiographic disease defined as any coronary lumen occlusion of 50% or more, 58% had disease. The clinical/treadmill test reports were sent to expert cardiologists and to 2 other groups, including randomly selected cardiologists and internists, who classified the patients as having high, low, or intermediate probability of disease and estimated a numerical probability from 0% to 100%. RESULTS: Forty-five expert cardiologists returned estimates on 336 patients, 37 randomly chosen practicing cardiologists returned estimates on 129 patients, 29 randomly chosen practicing internists returned estimates on 106 patients, 13 academic cardiologists returned estimates on 102 patients, and 27 academic internists returned estimates on 174 patients. When probability estimates were compared, the scores were superior to all physician groups (0.76 area under the receiver operating characteristic curve to 0.70 for experts [P=.046], 0.73 to 0.58 for cardiologists [P=.003], and 0.76 to 0.61 for internists [P=.006]). Using a probability cut point of greater than 70% for abnormal, predictive accuracy was 69% for scores compared with 64% for experts, 63% to 62% for cardiologists, and 70% to 57% for internists. CONCLUSION: Although most similar to the disease estimates of the presence of clinically significant angiographic coronary artery disease provided by the expert cardiologists, the scores outperformed the nonexpert physicians.     

Is clinical diagnosis of heart failure reliable?-Clinical judgement of cardiologists versus internists

BACKGROUND: Heart failure is a major cause of morbidity and mortality. Its diagnosis is mainly clinical. Most patients are seen by cardiologists and internists. However, it is not known whether clinical practices vary by specialty. We sought to evaluate the concordance in the clinical judgement of heart failure between cardiologists and internists. METHODS: Clinical judgement was investigated in 17 cardiologists and 25 internists from four district hospitals using the probability assessment of heart failure diagnosis in 30 case histories based on real patients. Use of clinical information in the diagnostic assessment was defined by the regression coefficients of multiple regression analysis, in which the diagnostic probability was the dependent variable and the clinical criteria the independent variables. The importance attributed to clinical variables, as reported by doctors in a questionnaire, and that of clinical practice, as expressed by the magnitude of the regression coefficients, were compared. RESULTS: We found no significant difference between cardiologists and internists. However, within each group of specialists, there was a wide inter-observer variation in the probability assessment of heart failure in the same case histories. The probability ranged from 25.6 to 83%. The relative importance of clinical variables actually used in diagnostic assessment was different from that reported by doctors. CONCLUSIONS: Cardiologists and internists do not differ in their clinical judgement of heart failure. However, within each group there can be wide discrepancies in the evaluation of the same case histories. This may be related to the different use of clinical information, as indicated by the wide confidence intervals of regression coefficients for clinical criteria. The way doctors use clinical information in practice differs from how they think they use it.     

Contenu des courriers échangés entre médecins généralistes et cardiologues : consensus d’après une étude Delphi

Aim of the studyTo obtain a consensus from a panel of experts (GP and cardiologists) on the elements to appear on the correspondence sent by GP at the patient's first consultation with the cardiologist and on the response of the cardiologist.MethodA list of proposals concerning the content of the exchanges between the GP and the cardiologist was established by a scientific council of three GPs and one cardiologist, based on a review of the literature and their practices. This list was submitted for evaluation to a panel of GP and cardiologists experts using the modified RAND/UCLA Delphi method.ResultsTwenty nine experts (16 MG and 13 cardiologists) participated in the two evaluation rounds. For the contents of the letter written by the GP, 11 themes have reached consensus: administrative data, reason for consultation, history of the disease, recent constants, current treatments, current or previous pathologies and cardiovascular risk factors, physical activity, psychosocial context, test results, question asked to the cardiologist, cardiologist's perimeter of action. For the contents of the letter of the cardiologist's response, 11 themes were agreed: administrative data, reason for consultation, previous information, clinical examination, ECG, ultrasound, other complementary examinations, answer to the question asked by the GP, dietary treatments, proposed treatments, proposal for follow-up and management.ConclusionThis study have reached consensus on the elements to appear on the letters exchanged between the GP and the cardiologist.     

Clinical activities and satisfaction of general internists,cardiologists, and ophthalmologists

To define factors that affect the levels of practice satisfaction of different specialities, an observer recorded the activities of 15 physicians in practice (nine general internists, three cardiologists, and three ophthalmologists) as they examined 304 clinic patients. General internists reported less satisfaction with their clinics than did the other physicians and attributed their satisfaction primarily to successful social interaction in 54% of visits, while cardiologists most often derived satisfaction from intellectual stimulation (50%) and ophthalmologists from medical success (81%). The general internists whom the authors observed are less satisfied with clinical encounters than are cardiologists and ophthalmologists and derive satisfaction mostly from social interaction, not biomedical aspects of care. Presented in part at the 14th annual meeting of the Society of General Internal Medicine, Seattle, Washington, May 1, 1991.     

Specialty-related differences in the epidemiology, clinical profile, management and outcome of patients hospitalized for heart failure; the OSCUR study. Oucome dello Scompenso Cardiaco in relazione all'Utilizzo delle Risore.

AIMS: This study was designed to identify potential specialty-related differences in the epidemiology, clinical profile, management and outcome of patients hospitalized for congestive heart failure in departments of cardiology or internal medicine. METHODS AND RESULTS: From 1 July to 31 December 1998, we prospectively recorded epidemiological and clinical data from patients with congestive heart failure consecutively admitted to 11 departments of cardiology and 12 departments of internal medicine in Liguria, a northern area of Italy. The overall study population included 749 patients; 22% were treated by cardiologists and 78% by internists (P<0.0001). Patients managed by cardiologists were more likely to undergo echocardiography (92% vs 37%), Holter monitoring (25% vs 3%) and exercise stress testing (20% vs 0.5%) than those managed by internists (P=0.001). At discharge, patients treated by cardiologists were more likely to be prescribed beta-blockers (41% to 4%) and ACE inhibitors (100% to 74%) than those treated by internists (P<0.0001), and the latter medication at higher dosages by cardiologists than internists. In addition, patients followed by cardiologists were younger (70+/-9 to 79+/-1 years;P<0.0001), more likely to be male (61% to 50%;P=0.011) and to have coronary artery disease (57% to 45%;P<0.006) than those followed by internists. Conversely, patients followed by internists were more likely to have diabetes, chronic obstructive pulmonary disease, atrial fibrillation and renal failure (P<0.03). In the overall study population, 53 patients (7%) died during hospitalization. Patients treated by cardiologists had a mortality not significantly different from that of patients treated by internists (10% and 6%, respectively;P=0.067), although congestive heart failure was more severe on admission in patients treated by cardiologists. CONCLUSION: Cardiologists follow published guidelines for congestive heart failure more strictly than internists, but treat a smaller number of patients who are younger, have more severe congestive heart failure and fewer co-morbidities than those managed by internists.     

Differences between patients with heart failure treated by cardiologists, internists, family physicians, and other physicians: analysis of a large, statewide database

BACKGROUND: The management of heart failure (HF) by cardiologists may be better than that of other physicians in that cardiologists' treatment choices more frequently conform with published guidelines and the results of clinical trials. Whether cardiologists' management of HF is more or less cost-effective is up for debate. METHODS: Information on all 1995 New York state hospital discharges assigned ICD-9-CM codes indicative of HF in the principal diagnosis position was obtained. Demographic and clinical characteristics, process of care, resource utilization, and short-term HF-related outcomes were compared between patients of cardiologists and patients of other physicians. RESULTS: A total of 44,926 patients were identified, with 10,506 (23%) receiving care from cardiologists, 28,300 (63%) from internists, 4812 (11%) from family practitioners, and 1308 (3%) from other physicians. Patients of cardiologists were younger, more frequently male, and less frequently residents of nursing homes. They were more likely to have associated cardiovascular diagnoses but less likely to have comorbid general medical conditions. Patients of cardiologists were more likely to undergo cardiac catheterization (9%) than those of internists (3%) and family practice (2%) physicians but had similar adjusted hospital length of stay and charges. Mortality and hospital readmission rates for HF were similar among the groups. Patients in the "other" group (managed mostly by surgeons) were the youngest, underwent more invasive and cardiac surgical procedures, and had the longest length of stay and highest hospital charges. CONCLUSIONS: Cardiologists' management of HF is not economically disadvantageous. The relations among physician specialty, process of care, resource utilization, and clinical outcomes require further study before rational and evidence-based health care staffing recommendations can be formulated.     

A community-wide survey of physician practices and attitudes toward cholesterol management in patients with recent acute myocardial infarction

BACKGROUND: Physicians' current attitudes and practices toward the management of high cholesterol levels in patients with recent acute myocardial infarction are not well defined. OBJECTIVE: To examine threshold levels of serum cholesterol and other factors that influence physicians' decision to prescribe lipid-lowering drugs and initiate dietary therapy in patients with recent acute myocardial infarction. METHODS: Community-wide questionnaire survey of general internists, cardiologists, and family physicians practicing in the Worcester, Mass, metropolitan area. RESULTS: Among the 257 responding physicians, lipid-lowering drug therapy was more likely to be initiated in younger patients at lower total serum and low-density lipoprotein (LDL) cholesterol levels than in older patients (P =.03). Younger physicians were more likely to initiate dietary and lipid-lowering drug therapy at lower total and LDL cholesterol levels than their older counterparts. Younger physicians also considered LDL cholesterol level the most important factor in initiating lipid-lowering drug therapy in contrast to older physicians who favored total cholesterol level (P =.001). General practice physicians were more likely to initiate dietary therapy at lower total cholesterol levels, but tended to initiate lipid-lowering drug therapy at higher total and LDL cholesterol levels compared with internists and cardiologists. Physicians reported that the most important factors that interfere with patients' use of lipid-lowering medication were concerns about medication costs, issues related to polypharmacy, and failure to recognize the importance of lipid-lowering drugs. Several physician-associated factors, including perceived importance of other cardiac drugs and provider responsibility, were associated with the nonuse of lipid-lowering medications. CONCLUSION: Educational and practice-based efforts remain necessary to remove potential barriers to the implementation of effective long-term cholesterol management in patients with recent acute myocardial infarction.     

Changes in cardiovascular risk factors by combined pharmacological and nonpharmacological strategies: the main results of the CELL Study

Objective. The objectives of the Cost Effectiveness of Lipid Lowering (CELL) study were twofold: (i) to evaluate the effect on overall cardiovascular risk of two types of health care advice (‘usual’ and ‘intensive’) given in primary care, with or without pharmacological medication, with the target being to attain a moderate decrease in cholesterol; (ii) to evaluate the ritual of daily medication on compliance with the health care advice. Design. A prospective, double-blind, randomized, controlled trial of 18 months' duration. Setting. The study was carried out in 32 health centres (out of a total of approximately 850) in Sweden. Subjects. In all, 681 subjects, aged 30–59 years, were randomized. They had at least two cardiovascular risk factors in addition to moderate primary hyperlipidaemia (total cholesterol of at least 6.50 mmol L^-1 on three occasions measured by Reflotron, triglycerides less than 4.0 mmol L^-1 and an LDL:HDL cholesterol ratio of more than 4.0). Most (87%) of the subjects were males; 626 subjects (92%) completed the 18-month follow-up. Intervention: Half the subjects were randomized to ‘intensive advice’ given in group sessions led by doctors and nurses in primary care. The other half received ‘usual advice’. In each of the two advice groups, one-third received an active lipid-lowering drug (pravastatin), one-third placebo, and one-third no drug at all. The tablets were titrated to achieve a 15% reduction in cholesterol. Main outcome measures. Changes in the overall Framingham risk score, and the development of adverse events in each group. Results. The change in Framingham risk score was significantly reduced only in subjects taking lipid-lowering medication (together with intensive advice-0.13; 95% CI -0.20,-0.06, and together with usual advice -0.16; 95% CI -0.23,-0.09). The other subjects receiving intensive advice tended to fare better than those on usual advice. Lifestyle was not influenced significantly over the study period. The ritual of daily medication did not affect the outcome. Conclusion. As expected, lipid-lowering medication reduced serum cholesterol as well as overall cardiovascular risk in subjects with several risk factors for cardiovascular disease. There was no additive effect of intensive advice to these subjects. However, there was a meagre but significant effect of intensive advice in subjects not receiving active lipid-lowering drugs. One explanation for this difference may be that those on active lipid-lowering medication who had substantial drops in cholesterol might have felt less inclined to change their lifestyle compared with those on other treatment regimens who had less successful drops in cholesterol. There was no benefit from the ritual of taking daily medication.     

Physician Judgement vs Model-Predicted Prognosis in Patients With Heart Failure

BackgroundPrevious evidence suggests that cardiologists and family doctors have limited accuracy in predicting patient prognosis. Predictive models with satisfactory accuracy for estimating mortality in patients with heart failure (HF) exist; physicians, however, seldom use these models. We evaluated the relative accuracy of physician vs model prediction to estimate 1-year survival in ambulatory patients with HF.MethodsWe conducted a single-centre cross-sectional study involving 150 consecutive ambulatory patients with HF >18 years of age with a left ventricular ejection fraction ≤40%. Each patient’s cardiologist and family doctor provided their predicted 1-year survival, and predicted survival scores were calculated using 3 models: HF Meta-Score, Seattle Heart Failure Model (SHFM), and Meta-Analysis Global Group in Chronic HF (MAGGIC) score. We compared accuracy between physician and model predictions using intraclass correlation (ICC).ResultsMedian predicted survival by HF cardiologists was lower (median 80%, interquartile range [IQR]: 61%-90%) than that predicted by family physicians (median 90%, IQR 70%-99%, P = 0.08). One-year median survival calculated by the HF Meta-Score (94.6%), SHFM (95.4%), and MAGGIC (88.9%,) proved as high or higher than physician estimates. Agreement among HF cardiologists (ICC 0.28-0.41) and family physicians (ICC 0.43-0.47) when compared with 1-year model-predicted survival scores proved limited, whereas the 3 models agreed well (ICC > 0.65).ConclusionsHF cardiologists underestimated survival in comparison with family physicians, whereas both physician estimates were lower than calculated model estimates. Our results provide additional evidence of potential inaccuracy of physician survival predictions in ambulatory patients with HF. These results should be validated in longitudinal studies collecting actual survival.     

社区医师与心内科医师心电图诊断及治疗的差异

目的:比较社区医师与心内科医师对心电图诊断及治疗的差异,了解远程心电图诊断系统安装的必要性。方法:心内科医师对503份心电图重新阅读并书写报告,作出相应的治疗,与社区医师作出的诊断及治疗方案对比,总结其差异性。结果:社区医师心电图诊断完全准确450份(89.5%),误诊53份(10.5%),心内科医师诊断完全准确498份(99.0%),误诊5份(1.0%),两者间比较有统计学差异(P0.01),社区医师诊断需要治疗例数475例(94.4%),不需要治疗28例(0.6%),心内科医师诊断需要治疗病例322例(64.0%),不需要治疗病例181例(36.0%),两者间比较有统计学差异(P0.01)。结论:社区医师对心电图的诊断的正确率显著低于心内科专业医师,而判断治疗需求的患者比例显著高于心内科医师。     

Cardiovascular risk profile and risk stratification of the hypertensive population attended by general practitioners and specialists in Spain. The CONTROLRISK study

The CONTROLRISK study was designed to determine the cardiovascular risk profile of the hypertensive population attended at primary care and specialist setting in Spain and to investigate whether physicians stratify the risk correctly, according to the 2003 European guidelines. A total of 8920 patients were recruited from primary care (n=4485) and specialist outpatient clinic (n=4435). The age criteria was 62.6+/-11.1 years; 51.6% were women. No differences were observed in the severity of hypertension. More than 85% presented other cardiovascular risk factors, similarly in both groups. Target organ damage (TOD) and associated clinical conditions (ACC) were more frequent in specialist setting (57.6 vs 34.3% and 39 vs 28.7%, both P<0.0001). The most common risk factor was age. The most frequently reported TOD was left ventricular hypertrophy (42.3 and 22.1%; P<0.0001). Ischemic heart disease was the most common ACC (21.5 vs 13.1%; P<0.0001). The risk profile was significantly higher in specialist population (75.1 vs 60.3% of patients belonged to high- or very high-risk groups). Specialists and primary care physicians stratified only 54.6 and 48% of their patients correctly, respectively (P<0.05). Both, specialists and general practitioners (GPs) strongly underestimated the risk. Very high-risk patients were adequately assessed only in 44.9% of cases by specialists and in 25.3% by GPs (P<0.001). More than half of the hypertensive patients attended by GPs in Spain belong to the high- or very high-risk groups. GPs and specialists tend to underestimate the cardiovascular risk in daily clinical practice, mainly in very high-risk patients.     

Smoking cessation practices of Dutch general practitioners, cardiologists, and lung physicians

STUDY OBJECTIVES: To assess and compare the smoking cessation practices and smoking behavior of Dutch general practitioners (GPs), cardiologists, and lung physicians. METHODS: We conducted questionnaire surveys among a random sample of 2000 Dutch GPs, all Dutch cardiologists (N=594), and all Dutch lung physicians (N=375). RESULTS: In total, 834 GPs (41.7%), 300 cardiologists (50.5%), and 258 lung physicians (68.8%) filled out and returned the questionnaire. The prevalence of current smokers was 8.2% among GPs, 4.3% among cardiologists, and 3.5% among lung physicians. Of the pharmacological aids for smoking cessation, physicians recommended bupropion most frequently, followed by nicotine patches and nicotine gum. More lung physicians recommended the use of these three aids (67.0%, 36.3% and 18.2%, respectively) than GPs (65.7%, 18.7% and 9.8%, respectively), and than cardiologists (31.6%, 19.7% and 13.2%, respectively). A higher proportion of lung physicians (69.3%) had referred at least one smoker to a nurse for smoking cessation treatment than cardiologists (25%), and than GPs (11.3%). CONCLUSIONS: Based on this national survey, one may conclude that the prevalence of current smoking among Dutch physicians is relatively low and has further decreased since 1988. Dutch GPs, cardiologists, and lung physicians mainly use interventions for smoking cessation that are easy to administer and are not very time consuming. Furthermore, more lung physicians than GPs and cardiologists recommend the use of bupropion, nicotine patch, and nicotine gum. When designing interventions for smoking cessation, one should take into account that physicians are often reluctant to provide interventions which demand much time. Therefore, intensive counseling of smokers who want to quit smoking may be more feasible for trained non-physicians, such as nurses.     

Race, medical researcher distrust, perceived harm, and willingness to participate in cardiovascular prevention trials

Minority underrepresentation exists in medical research including cardiovascular clinical trials, but the hypothesis that this relates to distrust in medical researchers is unproven. Therefore, we examined whether African American persons differ from white persons in perceptions of the risks/benefits of trial participation and distrust toward medical researchers, and whether these factors influence willingness to participate (WTP) in a clinical drug trial. Participants were self-administered a survey regarding WTP in a cardiovascular drug trial given to 1440 randomly selected patients from 13 Maryland outpatient cardiology and general medicine clinics. Patients reported their WTP, rated their perceived chances of experiencing health benefit and harm, and rated their distrust toward researchers. Of eligible participants, 70% responded, and 717 individuals were included: 36% African American and 64% white.African American participants possessed lower WTP than white participants (27% vs. 39%, p = 0.001) and had higher mean distrust scores than whites (p < 0.0001). African American participants more frequently reported that doctors would less fully explain research participation to them (24% vs. 13%, p < 0.001), use them as guinea pigs without their consent (72% vs. 49%, p < 0.001), prescribe medication as a way of experimenting on people without their knowledge (35% vs. 16%, p < 0.001), and ask them to participate in research even if it could harm them (24% vs. 15%, p = 0.002). African American participants also more often believed they could less freely ask their doctor questions (8% vs. 2%, p < 0.001) and that doctors had previously experimented on them without their consent (58% vs. 25%, p < 0.001). African American participants expressed lesser WTP than white participants after controlling for racial differences in age, sex, socioeconomic status and cardiovascular disease risk profiles (multivariable odds ratio [OR], 0.57; 95% confidence interval [CI], 0.39-0.85). The impact of race was attenuated and nonsignificant after adjustment for potential mediating factors of racial differences in medical researcher distrust and perceived risk of harm (explanatory model OR, 0.84; 95% CI 0.54-1.30). In summary, African American participants expressed markedly greater concerns about experiencing harm from participation in clinical trials and distrust toward medical researchers than white participants. These factors, in turn, appear to explain much of the resistance among African American persons to participate in clinical trials compared to white persons.