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T A Pearson

Publications and source records attributed to T A Pearson.

At least 37 records · Page 2Linked to original sources

Capacity for research in minority health: the need for infrastructure plus will.

Cardiovascular mortality has continued to decline, but racial disparities in cardiovascular diseases (CVD) continue to grow. To build the capacity to address these racial disparities, two things will be required. First, a research and policy infrastructure must be in place to provide guidance on what to do and how to do it. Second, the will to implement and activate this infrastructure must be present at the community and policy-making levels. The Jackson Heart Study is an example of a research infrastructure with the economic resources, scientific expertise, and technical manpower required to monitor, organize, assess, and follow a cohort of individuals over time to study the burden, natural history, predictive factors, and level of care for CVD in an African American community. The creation of will within the community for CVD research may require additional strategies than in the majority community, such as community organization and local policy development. These additional efforts at the community level should create a fertile environment to develop research and, ultimately, test strategies for reducing national disparities in cardiovascular health.

Attitude to Health↗

Capacity for research in minority health: the need for infrastructure plus will.

Cardiovascular mortality has continued to decline, but racial disparities in cardiovascular diseases (CVD) continue to grow. To build the capacity to address these racial disparities, two things will be required. First, a research and policy infrastructure must be in place to provide guidance on what to do and how to do it. Second, the will to implement and activate this infrastructure must be present at the community and policy-making levels. The Jackson Heart Study is an example of a research infrastructure with the economic resources, scientific expertise, and technical manpower required to monitor, organize, assess, and follow a cohort of individuals over time to study the burden, natural history, predictive factors, and level of care for CVD in an African American community. The creation of will within the community for CVD research may require additional strategies than in the majority community, such as community organization and local policy development. These additional efforts at the community level should create a fertile environment to develop research and, ultimately, test strategies for reducing national disparities in cardiovascular health.

Black People↗

Divergent approaches to the treatment of dyslipidemia with low levels of high-density lipoprotein cholesterol.

Further therapy should be considered for patients who have reached target low-density lipoprotein cholesterol (LDL-C) levels but have low plasma levels of high-density lipoprotein cholesterol (HDL-C) since rates of coronary artery disease continue to be high for a sizable proportion of this population. Lifestyle approaches include dietary changes, smoking cessation, moderate alcohol intake, concomitant drug reassessment, and specific coexistent conditions. Aggressive statin therapy still leaves a high residual rate of cardiac events. Other drug approaches include estrogen, fibrate, niacin therapy, and combinations of these agents. Recent results from an ongoing trial of combination extended-release prescription niacin plus lovastatin are very promising.

Cholesterol, HDL↗

The undertreatment of LDL-cholesterol: addressing the challenge.

Patients with dyslipidemia are at increased risk of coronary heart disease (CHD), while treatment to reduce low density lipoprotein cholesterol (LDL-C) concentrations lessens this risk. Consequently, the Lipid Treatment Assessment Project (L-TAP) was undertaken in the US to determine the extent to which primary care practitioners utilize lipid-lowering therapy and to evaluate the success of current therapeutic regimens, using the National Cholesterol Education Program (NCEP) guidelines as therapeutic targets. The L-TAP study, initiated in 1996 and completed in February 1997, recorded LDL-C levels in 4888 patients from 619 US practices. All patients had received lipid-lowering therapy for at least 3 months. The primary care practitioners involved in the study were questioned about the NCEP guidelines and the results confirmed that these physicians were representative of primary care practitioners in the USA. The 4888 patients were categorized according to risk: patients with <2 risk factors (RFs) but no CHD, those with >/=2 RFs but no CHD and patients with confirmed CHD. Overall, only 38% of the patients attained LDL-C target levels or had values lower than these goals. The greater the number of RFs, the lower the proportion of patients achieving target levels. LDL-C targets were less often attained in patients receiving dietary therapy only compared with those receiving lipid lowering drug treatment. However, there was good correlation between the success of treatment and both receipt of and compliance with dietary instruction. In conclusion, a large proportion of dyslipidemic patients who are being treated in primary care are not achieving NCEP target LDL-C levels.

Adult↗

Population benefits of cholesterol reduction: epidemiology, economics, and ethics.

Cardiovascular disease mortality-rate reductions have slowed in the United States in the last decade, suggesting that additional strategies are needed to reduce rates further. Population-wide cholesterol reduction is a promising approach. Selection of a particular strategy is less an issue of efficacy, which has been proven through numerous studies, than it is an issue of epidemiology, economics, and ethics. These 3 imperatives constitute the foundation of renewed efforts to reduce the US population's cholesterol levels. Epidemiologic imperatives include risk reduction in low-to-moderate risk individuals, who comprise approximately 30% of the population and one third of incident cases of coronary disease. Any cholesterol-lowering strategy must address the challenge of reducing the incidence of coronary disease; to do otherwise will result in an increasing prevalence of disease, with the attendant cost and disability burdens. Economic imperatives include the extension of preventive coverage to the low-to-moderate risk segment of the population, which currently is not included in any risk-reduction programs. Although cholesterol reduction with pharmacologic agents may not meet current standards for cost-effectiveness, over-the-counter (OTC) agents are under the rubric of individual, not societal, costs. Finally, current and proposed options for nonprescription cholesterol-lowering drugs raise a number of ethical issues such as beneficence, nonmaleficence, justice, and autonomy. Population-wide cholesterol reduction must be a mainstay for any strategy to reduce the burden of cardiovascular disease.

Adult↗

Raising low levels of high-density lipoprotein cholesterol is an important target of therapy.

Recent clinical trials in patients with coronary heart disease indicate, for the very first time, that increasing low levels of high-density lipoprotein (HDL) cholesterol significantly reduces the cumulative occurrence of cardiovascular and cerebrovascular events in patients whose only lipid abnormality was low HDL with normal levels of low-density lipoprotein (LDL) cholesterol and triglycerides. These data provide a compelling scientific basis for a more targeted and segmental approach to managing patients with dyslipidemia, where decreasing elevated levels of LDL cholesterol and increasing low levels of HDL cholesterol should comprise dual targets of pharmacotherapy.

Anticholesteremic Agents↗

The lipid treatment assessment project (L-TAP): a multicenter survey to evaluate the percentages of dyslipidemic patients receiving lipid-lowering therapy and achieving low-density lipoprotein cholesterol goals.

OBJECTIVE: To determine the percentage of patients in the multicenter Lipid Treatment Assessment Project receiving lipid-lowering therapy who are achieving low-density lipoprotein cholesterol (LDL-C) goals as defined by National Cholesterol Education Program (NCEP) guidelines. METHODS: Adult patients with dyslipidemia, who had been receiving the same lipid-lowering therapy for at least 3 months, were assessed at investigation sites. Lipid levels were determined once in each patient at the time of enrollment. The primary end point was the success rate, defined as the proportion of patients who achieved their LDL-C target level as specified by NCEP guidelines. RESULTS: A total of 4888 patients from 5 regions of the United States were studied. Of these, 23% had fewer than 2 risk factors for coronary heart disease (CHD) and no evidence of CHD (low-risk group), 47% had 2 or more risk factors and no evidence of CHD (high-risk group), and 30% had established CHD. Overall, only 38% of patients achieved NCEP-specified LDL-C target levels; success rates were 68% among low-risk patients, 37% among high-risk patents, and 18% among patients with CHD. Drug therapy was significantly (P< or =.001) more effective than nondrug therapy in all patient risk groups. However, many patients treated with lipid-lowering drugs did not achieve LDL-C target levels. CONCLUSIONS: Large proportions of dyslipidemic patients receiving lipid-lowering therapy are not achieving NCEP LDL-C target levels. These findings indicate that more aggressive treatment of dyslipidemia is needed to attain goals established by NCEP guidelines.

Adult↗

Nutritional interventions in cardiovascular disease: new challenges and opportunities.

New opportunities for control of cardiovascular disease (CVD) through nutritional interventions can be divided into three areas: nutritional intervention on newly identified causes of CVD; nutritional strategies to more efficiently or equitably employ current, proven interventions; and nutritional approaches to reduce costs and improve effectiveness so that benefits can be expanded to more of the population. Examples of newly identified causes of CVD amenable to nutritional intervention include fetal/early childhood malnutrition and gene-environment interactions. Examples of more efficient or equitable nutritional strategies include better nutrition education for healthcare providers, patient education resources on the Internet, and widely available functional foods or nutriceuticals. Nutritional approaches to improve cost-effectiveness include better availability of foods associated with reduced CVD risk (eg, fruits, vegetables, fish) and supplementation of the American diet. The advances in nutritional strategies described in this monograph have the potential for population-wide CVD risk reduction.

Cardiovascular Diseases↗

Does hypertension and its pharmacotherapy affect the quality of sexual function in women?

Considerable research has been conducted into the effects of antihypertensive drugs on male sexual functioning. This remains underexplored in women, even though almost half of treated hypertensives are women. An ambulatory medical record-based, case-control study was designed to study sexual function in treated and untreated hypertensive women and healthy controls. We conducted this study at a teaching hospital with satellite clinics in upstate New York. Of 3312 medical records reviewed, 640 premenopausal white women with or without mild hypertension (defined as blood pressure [BP] > or = 140/90 and < 160/110 mmHg), in heterosexual relationships, with no other significant medical history, were eligible. Of these, 241 women agreed to participate, and 224 (35%) completed both a self-administered questionnaire and a telephone interview. Analysis was conducted on 211 women (107 healthy controls, and 104 mild hypertensives, of whom 37 were unmedicated and 67 medicated). Questions on sexuality were classified into seven composite variables and later further divided. There were no demographic differences between participants and nonparticipants. Cases and controls differed only by age (P < .01); therefore, subsequent analysis was age-adjusted. Current smokers reported a significantly lower mean score for orgasm than did nonsmokers (P = .04). Women with unmedicated and medicated hypertension did not differ significantly on sexuality scores and were subsequently combined. Using age-adjusted ANOVA, women with hypertension reported significantly decreased lubrication and orgasm and increased pain compared to nonhypertensive women. There were no significant differences by ANOVA in the quality of sexual functioning between six treatment groups. In conclusion, the quality of female sexual functioning was quantified in an ambulatory outpatient setting. Hypertensive women, regardless of type of treatment, reported age-adjusted decrease in vaginal lubrication, less frequent orgasm, and more frequent pain when compared to nonhypertensive women. Emotional aspects of sexual functioning in hypertensive women do not appear to be impaired. These areas require further investigation. An incidental finding indicated diminished orgasm reported in current smokers, compared to nonsmokers, which was not associated with age or hypertension.

Adult↗

Variation of lipids and lipoproteins in premenopausal women compared with men and postmenopausal women. DELTA (Dietary Effects on Lipoproteins and Thrombogenic Activity) Investigators.

Numerous studies have reported cyclic fluctuations in lipids and lipoproteins as a function of the phase of the menstrual cycle. However, the reported patterns are quite variable and have led to an unclear picture of the influence of the menstrual cycle on the variability of lipids, and hence of the role of the menstrual cycle phase in the interpretation of serum lipids for premenopausal women. As part of the DELTA Study (Dietary Effects on Lipoproteins and Thrombogenic Activity), we evaluated the cyclic variation of circulating lipids and lipoproteins in 39 premenopausal women and compared intraindividual variances in these women, 18 postmenopausal women, and 46 men under conditions of tight dietary control. Cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride, apolipoproteins A-1 (apo A-1) and B-100 (apo B-100), and lipoprotein (a) [Lp(a)] all demonstrated cycling in the premenopausal women. However, the observed cycling accounts for only a small fraction of the total biologic variability of lipids in premenopausal women. The magnitude of total intraindividual variability based on coefficient of variation (CV) for these lipids in premenopausal women (CV, 4% to 8.1%) was similar to that found for men (CV, 4.3% to 9.1%) and for postmenopausal women (CV, 3.7% to 6.7%). These results suggest that protocols for screening and monitoring of serum lipids in premenopausal women need not differ from those used for men or postmenopausal women.

Adult↗

Race-related differences among patients with left ventricular dysfunction: observations from a biracial angiographic cohort. Harlem-Bassett LP(A) Investigators.

BACKGROUND: This study was designed to describe race-related differences in left ventricular function among a consecutive series of patients undergoing cardiac catheterization and to identify racial differences in coexistent medical and social conditions that are associated with the development of heart failure (HF). METHODS AND RESULTS: This was a prospective cohort study conducted at 2 university-affiliated teaching hospitals. We used the database of the Harlem-Bassett Lp(a) Study. We included all black (N = 143) or white (N = 313) patients from the main study database for whom complete survey, laboratory, coronary angiographic, and ventriculographic data were available. "Left ventricular dysfunction" was arbitrarily defined as an ejection fraction < or =0.40 or prior pharmacologic treatment for HF. We found that blacks were younger, had a higher proportion of women, and had fewer years of formal education than their white counterparts. Coronary artery disease was less common among blacks, although this group had a higher prevalence of hypertension, diabetes, cigarette smoking, illicit drug use, and alcohol consumption. Black patients had a higher prevalence of previous treatment for HF, larger left ventricular volumes, and lower ejection fractions than white patients. Blacks with left ventricular dysfunction were more likely to have had a previous myocardial infarction or a history of hypertension compared with those without left ventricular dysfunction. CONCLUSIONS: Regarding left ventricular dysfunction and HF, we conclude that blacks seem to have a much higher burden of disease than whites. Our observations support prior evidence that hypertension is linked to race-related differences in the epidemiology of HF. The interaction between race and access to quality care for HF remains an important area for future investigation.

Adult↗

Lowering dietary saturated fat and total fat reduces the oxidative susceptibility of LDL in healthy men and women.

The present study examined the effects of reducing dietary total fat and saturated fat (SFA) on LDL oxidative susceptibility in 27 healthy men and women (age 24-65 y). Each subject consumed each of three diets for 8 wk: an average American diet (AAD, 34% energy from fat, 15% from SFA), a Step-1 diet (29% fat, 9% SFA) and a very low SFA diet (Low-Sat, 25% fat, 6% SFA). In vitro LDL oxidation was assessed by copper-mediated oxidation, as measured by the kinetics of conjugated diene formation and lipid peroxide formation. Compared with the AAD, plasma LDL-cholesterol (LDL-C) and HDL cholesterol levels were 8% lower (P: = 0.16 and P: = 0.11, respectively), in subjects when they consumed the Step-1 diet and 11% (P: < 0.03) and 14% (P: < 0.057) lower, respectively, when they consumed the Low-Sat diet. Conjugated diene production and oxidation rate were 7% (P: < 0. 05) and 9% (P: < 0.05) lower, respectively. The reduction of lipid peroxide formation was 9% (P: < 0.05) in subjects when they consumed the Low-Sat diet vs. the AAD. In addition, lipid peroxide and conjugated diene formation were positively correlated with plasma total and LDL-C and apolipoprotein B (apo B) levels (r = 0.5-0.6, P: < 0.001), suggesting that quantity of LDL is an important determinant of oxidative modification. Furthermore, at the same level of apo B or LDL-C, LDL from subjects when they consumed either Step-1 or Low-Sat diets was less susceptible (P: < 0.05) to oxidation than those when they consumed the AAD, suggesting that qualitative changes also affect LDL oxidative susceptibility. Therefore, the benefits of lowering dietary SFA may extend beyond decreasing LDL-C levels and include favorable qualitative changes in LDL that further decrease risk of coronary heart disease.

Adult↗

Plasma sphingomyelin level as a risk factor for coronary artery disease.

Only a fraction of the clinical complications of atherosclerosis are explained by known risk factors. Animal studies have shown that plasma sphingomyelin (SM) levels are closely related to the development of atherosclerosis. SM carried into the arterial wall on atherogenic lipoproteins may be locally hydrolyzed by sphingomyelinase, promoting lipoprotein aggregation and macrophage foam cell formation. A novel, high-throughput, enzymatic method to measure plasma SM levels has been developed. Plasma SM levels were related to the presence of coronary artery disease (CAD) in a biethnic angiographic case-control study (279 cases and 277 controls). Plasma SM levels were higher in CAD patients than in control subjects (60+/-29 versus 49+/-21 mg/dL, respectively; P:<0. 0001). Moreover, the ratio of SM to SM+phosphatidylcholine (PC) was also significantly higher in cases than in controls (0.33+/-0.13 versus 0.29+/-0.10, respectively; P:<0.0001). Similar relationships were observed in African Americans and whites. Plasma SM levels showed a significant correlation with remnant cholesterol levels (r=0.51, P:<0.0001). By use of multivariate logistic regression analysis, plasma SM levels and the SM/(SM+PC) ratio were found to have independent predictive value for CAD after adjusting for other risk factors, including remnants. The odds ratio (OR) for CAD was significantly higher for the third and fourth quartiles of plasma SM levels (OR 2.81 [95% CI 1.66 to 4.80] and OR 2.33 [95% CI 1.38 to 3. 92], respectively) as well as the SM/(SM+PC) ratio (OR 1.95 [95% CI 1.10 to 3.45] and OR 2.33 [95% CI 1.34 to 4.05], respectively). The findings indicate that human plasma SM levels are positively and independently related to CAD. Plasma SM levels could be a marker for atherogenic remnant lipoprotein accumulation and may predict lipoprotein susceptibility to arterial wall sphingomyelinase.

Case-Control Studies↗

High levels of Lp(a) with a small apo(a) isoform are associated with coronary artery disease in African American and white men.

Elevated levels of lipoprotein(a) [Lp(a)] and the presence of small isoforms of apolipoprotein(a) [apo(a)] have been associated with coronary artery disease (CAD) in whites but not in African Americans. Because of marked race/ethnicity differences in the distribution of Lp(a) levels across apo(a) sizes, we tested the hypothesis that apo(a) isoform size determines the association between Lp(a) and CAD. We related Lp(a) levels, apo(a) isoforms, and the levels of Lp(a) associated with different apo(a) isoforms to the presence of CAD (>/=50% stenosis) in 576 white and African American men and women. Only in white men were Lp(a) levels significantly higher among patients with CAD than in those without CAD (28.4 versus 16.5 mg/dL, respectively; P:=0.004), and only in this group was the presence of small apo(a) isoforms (<22 kringle 4 repeats) associated with CAD (P:=0.043). Elevated Lp(a) levels (>/=30 mg/dL) were found in 26% of whites and 68% of African Americans, and of those, 80% of whites but only 26% of African Americans had a small apo(a) isoform. Elevated Lp(a) levels with small apo(a) isoforms were significantly associated with CAD (P:<0.01) in African American and white men but not in women. This association remained significant after adjusting for age, diabetes mellitus, smoking, hypertension, HDL cholesterol, LDL cholesterol, and triglycerides. We conclude that elevated levels of Lp(a) with small apo(a) isoforms independently predict risk for CAD in African American and white men. Our study, by determining the predictive power of Lp(a) levels combined with apo(a) isoform size, provides an explanation for the apparent lack of association of either measure alone with CAD in African Americans. Furthermore, our results suggest that small apo(a) size confers atherogenicity to Lp(a).

Black or African American↗