Copeptin as a non-invasive biomarker in chronic thromboembolic pulmonary hypertension

Introduction

Copeptin is the C-terminal fragment of the precursor protein of vasopressin. In acute pulmonary embolism, copeptin has been suggested to be a strong predictor of outcome and to provide additional predictive value to the established cardiac biomarkers high-sensitivity cardiac troponin and N-terminal pro-brain natriuretic peptide (NT-proBNP). Chronic thromboembolic pulmonary hypertension (CTEPH) is diagnosed in about 5% of patients who survive acute pulmonary embolism. Individualized risk stratification remains a challenge in the work-up of CTEPH patients.

Purpose

The current study investigated whether copeptin has the potential to aid the stratification of patients who have experienced pulmonary embolism and CTEPH patients. We examined the baseline (BL) levels and dynamics of copeptin during therapy in CTEPH patients who underwent balloon pulmonary angioplasty (BPA) or pulmonary endarterectomy (PEA). Moreover, the study compared copeptin levels between patients with or without therapy response.

Methods

The study included a total of 125 CTEPH patients scheduled for treatment. A total of 78 underwent staged BPA and 64 underwent PEA. In accordance with recent studies from our group, therapy success was defined as a decrease in meanPAP ≥25% and PVR ≥35% or a normalization below the thresholds defining pulmonary hypertension. Blood samples were collected at BL, prior to each BPA session in the BPA cohort, and at follow-up (FU) 6 months after BPA or 12 months after PEA. Copeptin was measured in thawed serum aliquots by an immunochemical method.

Results

The 78 patients in the BPA cohort underwent a mean of 6 BPA procedures each; there were a total of 413 interventions. The hemodynamic clinical and functional status the CTEPH patients improved after BPA and PEA therapy: meanPAP (BL: 43±9 mmHg vs. FU: 27±9 mmHg; p<0.001); PVR (BL: 7.6±3.4 WU vs. FU: 3.8±2.0 WU; p<0.001); RAP (BL: 7.9±5.8 mmHg vs. FU: 5.4±2.7 mmHg; p<0.001); WHO functional class [BL: I:0 / II:25 / III:80 / IV:20 vs. FU: I:56 / II:57 / III:10 / IV:2]; 6-minute-walk distance (BL: 405±99 m vs. FU: 456±112 m; p<0.001).

The median serum levels of copeptin [BL 7.7 (4.6–14.2) pmol/L vs. FU 6.3 (3.9–12.5); p=0.009] and NT-proBNP [BL: 811 (157–1857) ng/L vs. FU: 142 (72–335) ng/L p<0.001] decreased significantly after therapy. The copeptin levels did not correlate with hemodynamics at BL: PVR (rrs=0.02; p=0.79) and meanPAP (rrs=0.03; p=0.75). The copeptin levels at BL (AUC=0.61) and the relative change (AUC=0.53) did not predict the endpoint of therapy response.

Conclusions

Copeptin levels are elevated in CTEPH patients compared with normal values in the literature. Although copeptin is known to provide additional value in the context of risk stratification in acute pulmonary embolism, it failed to provide additional diagnostic benefit in CTEPH in the current study.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): SFB 1213 area CP01

[Comprehensive life style changes by coronary patients--an intervention study]

In an intervention trial 31 coronary patients participated in a comprehensive lifestyle change program and 43 control patients received the usual care of the conventional cardiac rehabilitation system. First preliminary findings show that the patients in the intervention group not only improved their health related lifestyle but also increased their exercise capacity and reduced depression, while there was no substantial improvement in the control group. Up to the present, the existing data indicate that German heart patients are able to make comprehensive lifestyle changes and that these changes have positive effects on biomedical and psychosocial variables.

Changes in myocardial perfusion abnormalities by positron emission tomography after long-term, intense risk factor modification

OBJECTIVE

To quantify changes in size and severity of myocardial perfusion abnormalities by positron emission tomography (PET) in patients with coronary artery disease after 5 years of risk factor modification.

DESIGN

Randomized controlled trial.

SETTING

Outpatient community setting.

INTERVENTION

Randomization of patients to risk factor modification consisting of very low-fat vegetarian diet, mild to moderate exercise, stress management, and group support (experimental group, n = 20) or to usual care by their own physicians, consisting principally of antianginal therapy (control group, n = 15).

MAIN OUTCOME MEASURES

Quantitative coronary arteriography and PET at baseline and 5 years after randomization. Automated, objective measures of size and severity of perfusion abnormalities on rest-dipyridamole PET images and of stenosis severity on arteriograms were made by computer algorithms.

RESULTS

Size and severity of perfusion abnormalities on dipyridamole PET images decreased (improved) after risk factor modification in the experimental group compared with an increase (worsening) of size and severity in controls. The percentage of left ventricle perfusion abnormalities outside 2.5 SDs of those of normal persons (based on 20 disease-free individuals) on the dipyridamole PET image of normalized counts worsened in controls (mean +/- SE, + 10.3% +/- 5.6%) and improved in the experimental group (mean +/- SE, -5.1% +/- 4.8%) (P = .02); the percentage of left ventricle with activity less than 60% of the maximum activity on the dipyridamole PET image of normalized counts worsened in controls (+13.5% +/- 3.8%) and improved in the experimental group (-4.2% +/- 3.8%) (P = .002); and the myocardial quadrant on the PET image with the lowest average activity expressed as a percentage of maximum activity worsened in controls (-8.8% +/- 2.3%) and improved in the experimental group (+4.9% +/- 3.3%) (P = .001). The size and severity of perfusion abnormalities on resting PET images were also significantly improved in the experimental group as compared with controls. The relative magnitude of changes in size and severity of PET perfusion abnormalities was comparable to or greater than the magnitude of changes in percent diameter stenosis, absolute stenosis lumen area, or stenosis flow reserve documented by quantitative coronary arteriography.

CONCLUSIONS

Modest regression of coronary artery stenoses after risk factor modification is associated with decreased size and severity of perfusion abnormalities on rest-dipyridamole PET images. Progression or regression of coronary artery disease can be followed noninvasively by dipyridamole PET reflecting the integrated flow capacity of the entire coronary arterial circulation.

Improved stenosis geometry by quantitative coronary arteriography after vigorous risk factor modification

This study is a randomized, controlled, blinded, arteriographic trial to determine the effects of a low-cholesterol, low-fat, vegetarian diet, stress management and moderate aerobic exercise on geometric dimensions, shape and fluid dynamic characteristics of coronary artery stenoses in humans. Complex changes of different primary stenosis dimensions in opposite directions or to different degrees cause stenosis shape change with profound effects on fluid dynamic severity, not accounted for by simple percent narrowing. Accordingly, all stenosis dimensions were analyzed, including proximal, minimal, distal diameter, integrated length, exit angles and exit effects, determining stenosis shape and a single integrated measure of stenosis severity, stenosis flow reserve reflecting functional severity. In the control group, complex shape change and a stenosis-molding characteristic of statistically significant progressing severity occurred with worsening of stenosis flow reserve. In the treated group, complex shape change and stenosis molding characteristic of significant regressing severity was observed with improved stenosis flow reserve, thereby documenting the multidimensional characteristics of regressing coronary artery disease in humans.

Cook-Medley Hostility scale and subsets: relationship to demographic and psychosocial characteristics in young adults in the CARDIA study

This report describes the relationships between scores obtained on the Cook-Medley Hostility (Ho) scale and race, education, gender, and age in a sample of 5115 young adult participants in a prospective study of coronary heart disease (CHD) risk factors. Large differences were observed in total Ho scale scores and in six recently identified subsets according to race, education, gender, and age. Young black males with limited education had the highest Ho scale levels (mean = 26.2) while older white females with more education had the lowest levels (mean = 15.5). In all subgroups, education was inversely associated with hostility. The findings suggest a possible mechanism whereby CHD risk is higher in males than females, in the less educated than the more educated, and in blacks than whites. In all race and gender subgroups, total Ho scale scores and the six subsets were positively correlated with negative life events and negatively correlated with social support, supporting a pattern of psychosocial vulnerability found in other studies.

Selection, training, and quality control of Type A interviewers in a prospective study of young adults

This paper describes Type A/B interviewer selection, training, and quality control results in a prospective study of coronary artery risk development in young adults (CARDIA). Interviewer behaviors from 152 CARDIA structured interviews were audited and compared with 747 Western Collaborative Group Study (WCGS) interviews and 577 Multiple Risk Factor Intervention Trial (MRFIT) interviews. The results show success in modeling the CARDIA interviewer behaviors on those of the WCGS. CARDIA interviews were very similar to WCGS interviews for interview length, number of questions asked, and speed of speaking; they were similar to MRFIT interviews in latency of asking questions. CARDIA interviewer behaviors remained fairly consistent over the four time periods. Comparing the clinics, there were regional differences in latency of asking and speed of speaking, with the Southern clinic having a longer asking latency and speaking more slowly. There were differences between individual interviewers in most characteristics, particularly those that were more free to vary. The study provides procedures and guidelines designed to maintain quality control of the structured interview process.

Speech characteristics and coronary heart disease incidence in the multiple risk factor intervention trial

To assess whether speech characteristics descriptive of Type A behavior were related to coronary heart disease (CHD) incidence in the Multiple Risk Factor Intervention Trial, we scored voice emphasis, speed of speaking, latency of answering, and answer content from 577 audiotaped structured interviews in a case-control design which included all 193 individuals who incurred CHD during the 7-year follow-up. These were matched with 384 CHD-free controls. Multivariate analyses showed that subjects' voice emphasis [relative risk ratio (RR) = 1.25, p = .02] and latency of answering (RR = .78, p = .02) were significantly associated with CHD incidence when controlled for baseline levels of diastolic blood pressure, serum cholesterol, and cigarette smoking.

Self-reference and coronary heart disease incidence in the Western Collaborative Group Study

Previous research has indicated that the spoken frequency of the self-references "I," "me," and "my" in a structured interview was prospectively related to coronary heart disease (CHD). To assess whether the findings would replicate in another population, we conducted a case-control analysis of 750 structured interviews from the Western Collaborative Group Study. To measure self-references, auditors counted all first person pronouns (I, me, my) and clauses spoken in the audiotaped baseline structured interviews. Matched multiple logistic regression analyses, with or without adjustment for major CHD risk variables, indicated that those who incurred CHD did not self-reference more frequently or densely than the CHD-free control subjects. Type As spoke more clauses and more total self-references but did not have a higher density of self-references than Type Bs. The results question both the method for measuring self-references and the hypothesis that self-referencing are associated with CHD.

Speech characteristics and behavior-type assessment in the Multiple Risk Factor Intervention Trial (MRFIT) structured interviews

Four speech characteristics (SCs) were scored from 626 audiotaped Structured Interviews (SIs) designed to assess behavior type in the Multiple Risk Factor Intervention Trial (MRFIT). Analyses suggested that interviewers relied upon respondents' voice emphasis, speed of speaking, speed of answering, and answer content (in that order) for behavior typing. Across the clinics, there were large differences in the degree that each interviewer and auditor used these SCs for behavior-type judgments, and these differences appear to be related to differences in interauditor reliability. Correlations between the various SCs were very low, suggesting that key operationally defined characteristics of Type A behavior occurred independently in the SI. Analysis of interviewers' SCs indicated that they spoke and asked questions more quickly of Type A than Type B subjects--suggesting that interviewers' behaviors were biased by respondents' behavior type. Overall, the findings indicate the complexity of the behavior-type judgment process and how the criteria for assessment may change depending upon interviewer or population differences.

Patient exposition and provider explanation in routine interviews and hypertensive patients' blood pressure control

Hypertensive patients' expressing themselves in their own words (Exposition) and providers' giving information (Explanation) during medical interviews were hypothesized to be associated with subsequent blood pressure control. Transcripts of routine return visits to clinics in low-income areas of Houston, TX, were coded using the Verbal Response Modes (VRM) system. VRM indexes of Patient Exposition and Provider Explanation were tested in relation to systolic and diastolic blood pressure obtained during home interviews 2 weeks after the clinic visits. Patient Exposition was significantly correlated with reductions in systolic and diastolic blood pressure from clinic visit to home interview, and Provider Explanation was significantly correlated with lower diastolic blood pressure at home interview. The results suggest that patients' and providers' verbal behavior in medical interviews should be included in predictive models of blood pressure control.

Self-involvement and coronary heart disease incidence in the multiple risk factor intervention trial

At intake into a multiple coronary heart disease (CHD) risk factor intervention trial, 3110 individuals were interviewed to assess Type A behavior. After an average of 7 years followup, the 193 individuals who manifested their first CHD event were matched with 384 CHD-free individuals. To assess self-involvement, auditors counted all verbal self-references (I, me, my) and clauses spoken in the audiotaped baseline interviews. Self-references were entered into multiple logistic regression analyses that controlled for age, diastolic blood pressure, cholesterol, cigarette smoking, and Type A behavior. Relative to matched controls, those who incurred CHD spoke more self-references at baseline [p = 0.017; relative risk (RR) = 1.20], but did not self-reference more densely. Relative to matched controls, those who died from CHD spoke more self-references (p = 0.008; RR = 1.62) and self-referenced more densely (p = 0.027; RR = 1.54). Neither total self-references nor self-reference density was predictive of angina pectoris or nonfatal myocardial infarction (MI). However, among those who incurred MI, self-reference frequency was the strongest predictor of mortality among all the measured risk factors (p = 0.01, RR = 2.0). The results suggest that self-involvement is related to CHD incidence.

Advances in controlling hypertension in low-income patients

Since hypertension is the foremost problem in minority and low-income populations treated in our community health centers, in 1976 we introduced a protocol that standardized diagnostic criteria and a step-care approach to the treatment of hypertension. In 1980, we modified the original protocol with guidelines for dietary management and an outline for improving physician-patient communication and health education. We hypothesized that implementing the protocol (and later modifications) would be associated with improved identification and control of hypertension. We conducted a cross-sectional study of hypertensive patients' charts in three community health centers in 1973, 1978, and 1982, and determined the status of blood pressure (BP) control of those patients by the end of the year. In 1973 (before protocol), 4 percent of hypertensives were undiagnosed and untreated, and 20 percent were lost to follow-up. Among those who remained under care, only 33 percent were under control (BP less than 160/95 mm Hg). In 1978, two years after the protocol was introduced, there were fewer undiagnosed and untreated patients (2 percent), but the number lost to follow-up increased to 31 percent. The proportion of hypertensives under control increased to 70 percent. In 1982, two years after the modifications to the protocol were introduced, the proportion of patients lost to follow-up decreased to 28 percent, and the proportion of patients with controlled blood pressure increased to 79 percent. The improved level of control was statistically significant at p less than .0001 (chi-square test).(ABSTRACT TRUNCATED AT 250 WORDS)

Physician communication to patients regarding medications

An analysis of 11 physicians' speech content regarding medications was conducted on 267 encounters with hypertensive patients. Scored were categories for questions, instructions, directions to take and justifications for taking medications. The median inter-auditor agreement was 83%. The results indicate that the physicians asked few questions and gave few instructions for patients on stable drug regimens; however, for newly prescribed drugs and changed regimens the provided information doubled: there were instructions for 77%, medication-taking commands for 31% and justification for taking medications for 21% of all medications. Other results indicate that that physicians did not discriminate by age, sex or race in quantity of speech about medication, but they did ask more questions of patients who saw a different physician on the previous visit. The results suggest that the system of scoring speech was reliable and captured the physicians adjustments to their patients' and their own needs for information.

A three-dimensional model for teaching about hypertension

We present a model of the cardiovascular system used to teach patients about the nature, risks, and treatment of hypertension. We designed the model to help providers explain abstract principles of cardiovascular function through graphic representations that patients can see, feel and hear. This article describes the model, discusses the concepts that providers can illustrate to patients, and includes an outline followed by providers of our community health centers in educating hypertensive patients.

Type A behavior, self-involvement, and coronary atherosclerosis

Prior to coronary angiography, 150 men were assessed for Type A behavior using the structured interview and two questionnaire measures. The results show no relationship between Type A behavior and extent of coronary artery disease (CAD). A second finding is that the number of self-references (I, me, my) derived from speech in the structured interview correlated positively with the number of previous myocardial infarctions and the extent of CAD; self-references correlated negatively with time on the treadmill and catheterization ejection fraction. Multiple regression analyses show self-references to remain a significant correlate of extent of disease when controlled for age, blood pressure, cholesterol, and Type A behavior.

Type A behavior, self-involvement, and cardiovascular response

Coronary-prone Type A and noncoronary-prone Type B students were challenged by a battery of tasks including cold pressor, mental arithmetic, behavior type interview, and the generation and expression of emotions. Measures of blood pressure, heart rate, and digital vasoconstriction were intercorrelated with reported distress, performance, speech characteristics, emotional intensity, and self-references. The major difference between the two behavior types concerned self-references, measured as the frequency of personal pronouns employed in speech. The Type A's who referred to themselves frequently had a markedly higher systolic blood pressure, a slightly higher diastolic blood pressure, a lower heart rate, higher distress ratings to cold water, and more extreme voice emphasis and emotional intensity than Type A's who referred to themselves less frequently. The Type B's have little relationship of self-references to any of the measures taken. The possible role of self-involvement in generating Type A behavior and cardiovascular response is discussed.

Type A assessment and interaction in the behavior pattern interview

Speech characteristics of both an interviewer and respondents were scored from recorded interviews that were conducted to assess Type A behavior. A stepwise regression analysis indicated that the expressive speech characteristics were the best discriminators of behavior typing by the interview. A similar analysis employing the Jenkins Activity Survey as the criterion for typing showed that only the content of the respondents' answers predicted typing. The Activity Survey and the interview assessment appeared to classify individuals on independent aspects of Type A behavior. Correlations of the interviewer's speech characteristics with the respondents' feeling reports and speech characteristics show stronger associations among these variables for Type A than for Type B subjects. The analysis of speech characteristics id discussed as a method of refining the assessment of behavior type and of identifying the psychological predictors of coronary heart disease.

Patient exposition and provider explanation in routine interviews and hypertensive patients' blood pressure control

Hypertensive patients' expressing themselves in their own words (Exposition) and providers' giving information (Explanation) during medical interviews were hypothesized to be associated with subsequent blood pressure control. Transcripts of routine return visits to clinics in low-income areas of Houston, TX, were coded using the Verbal Response Modes (VRM) system. VRM indexes of Patient Exposition and Provider Explanation were tested in relation to systolic and diastolic blood pressure obtained during home interviews 2 weeks after the clinic visits. Patient Exposition was significantly correlated with reductions in systolic and diastolic blood pressure from clinic visit to home interview, and Provider Explanation was significantly correlated with lower diastolic blood pressure at home interview. The results suggest that patients' and providers' verbal behavior in medical interviews should be included in predictive models of blood pressure control.