Cardiovascular Risk Prediction with Ultrasound

This paper addresses primary care physicians, cardiologists, internists, angiologists and doctors desirous of improving vascular risk prediction in primary care. Many cardiovascular risk factors act aggressively on the arterial wall and result in atherosclerosis and atherothrombosis. Cardiovascular prognosis derived from ultrasound imaging is, however, excellent in subjects without formation of intimal thickening or atheromas. Since ultrasound visualises the arterial wall directly, the information derived from the arterial wall may add independent incremental information to the knowledge of risk derived from global risk assessment. This paper provides an overview on plaque imaging for vascular risk prediction in two parts: Part 1: Carotid IMT is frequently used as a surrogate marker for outcome in intervention studies addressing rather large cohorts of subjects. Carotid IMT as a risk prediction tool for the prevention of acute myocardial infarction and stroke has been extensively studied in many patients since 1987, and has yielded incremental hazard ratios for these cardiovascular events independently of established cardiovascular risk factors. However, carotid IMT measurements are not used uniformly and therefore still lack widely accepted standardisation. Hence, at an individual, practicebased level, carotid IMT is not recommended as a risk assessment tool. The total plaque area of the carotid arteries (TPA) is a measure of the global plaque burden within both carotid arteries. It was recently shown in a large Norwegian cohort involving over 6000 subjects that TPA is a very good predictor for future myocardial infarction in women with an area under the curve (AUC) using a receiver operating curves (ROC) value of 0.73 (in men: 0.63). Further, the AUC for risk prediction is high both for vascular death in a vascular prevention clinic group (AUC 0.77) and fatal or nonfatal myocardial infarction in a true primary care group (AUC 0.79). Since TPA has acceptable reproducibility, allows calculation of posttest risk and is easily obtained at low cost, this risk assessment tool may come in for more widespread use in the future and also serve as a tool for atherosclerosis tracking and guidance for intensity of preventive therapy. However, more studies with TPA are needed. Part 2: Carotid and femoral plaque formation as detected by ultrasound offers a global view of the extent of atherosclerosis. Several prospective cohort studies have shown that cardiovascular risk prediction is greater for plaques than for carotid IMT. The number of arterial beds affected by significant atheromas may simply be added numerically to derive additional information on the risk of vascular events. A new atherosclerosis burden score (ABS) simply calculates the sum of carotid and femoral plaques encountered during ultrasound scanning. ABS correlates well and independently with the presence of coronary atherosclerosis and stenosis as measured by invasive coronary angiogram. However, the prognostic power of ABS as an independent marker of risk still needs to be elucidated in prospective studies. In summary, the large number of ways to measure atherosclerosis and related changes in human arteries by ultrasound indicates that this technology is not yet sufficiently perfected and needs more standardisation and workup on clearly defined outcome studies before it can be recommended as a practice-based additional risk modifier.

Fungal infection as a risk factor for HIV disease progression among patients with a CD4 count above 200/microl in the era of cART.

The identification of clinical risk factors for AIDS in patients with preserved immune function is of significant interest. We examined whether patients with fungal infection (FI) and CD4 cell count >or=200/microl were at higher risk of disease progression in the era of cART. 11,009 EuroSIDA patients were followed from their first CD4 cell count >or=200/microl after 1 January 1997 until progression to any non-azoles/amphotericin B susceptible (AAS) AIDS disease, last visit or death. Initiation of antimycotic therapy (AMT) was used as a marker of FI and was modelled as a time-updated covariate using Poisson regression. After adjustment for current CD4 cell count, HIV-RNA, starting cART and diagnosis of AAS-AIDS, AMT was significantly associated with an increased incidence of non-AAS-AIDS (IRR=1.55, 95% CI 1.17-2.06, p=0.0024). Despite low incidence of AIDS in the cART era, FI in patients with a CD4 cell count >or=200/microl is associated with a 55% higher risk of non-AAS-AIDS (95% confidence interval 1.17-2.06, p=0.0024). These data suggest that patients with FI are more immune compromized than would be expected from their CD4 cell count alone. FI can be used as a clinical marker for disease progression and indirect indicator for initiation/changing cART in settings where laboratory facilities are limited.

Effect of hormone replacement therapy on vasomotor function of the coronary microcirculation in post-menopausal women with medically treated cardiovascular risk factors.

Aims The aim of this study was to evaluate the effect of hormone replacement therapy (HRT) on coronary vasomotor function in post-menopausal women (PM) with medically treated cardiovascular risk factors (RFs) in a cross-sectional and a longitudinal follow-up (FU) study. Methods and results Myocardial blood flow (MBF) response to cold pressor testing (CPT) and during pharmacologically induced hyperaemia was measured with positron emission tomography in pre-menopausal women (CON), in PM with HRT and without HRT, and repeated in PM after a mean FU of 24 +/- 14 months. When compared with CON at baseline, the endothelium-related change in MBF (DeltaMBF) to CPT progressively declined in PM with HRT and without HRT (0.35 +/- 0.23 vs. 0.24 +/- 0.20 and 0.16 +/- 0.12 mL/g/min; P = 0.171 and P = 0.021). In PM without HRT and in those with HRT at baseline but with discontinuation of HRT during FU, the endothelium-related DeltaMBF to CPT was significantly less at FU than at baseline (0.05 +/- 0.19 vs. 0.16 +/- 0.12 and -0.03 +/- 0.14 vs. 0.25 +/- 0.18 mL/g/min; P = 0.023 and P = 0.001), whereas no significant change was observed in PM with HRT (0.19 +/- 0.22 vs. 0.23 +/- 0.22 mL/g/min; P = 0.453). Impaired hyperaemic MBFs when compared with CON were not significantly altered from those at baseline exam. Conclusion Long-term administration of oestrogen may contribute to maintain endothelium-dependent coronary function in PM with medically treated cardiovascular RFs.

Current cardiovascular risk management patterns with special focus on lipid lowering in daily practice in Switzerland.

Background: There may be a considerable gap between LDL cholesterol (LDL-C) and blood pressure (BP) goal values recommended by the guidelines and results achieved in daily practice. Design Prospective cross-sectional survey of cardiovascular disease risk profiles and management with focus on lipid lowering and BP lowering in clinical practice. Methods: In phase 1, the cardiovascular risk of patients with known lipid profile visiting their general practitioner was anonymously assessed in accordance to the PROCAM-score. In phase 2, high-risk patients who did not achieve LDL-C goal less than 2.6 mmol/l in phase 1 could be further documented. Results: Six hundred thirty-five general practitioners collected the data of 23 892 patients with known lipid profile. Forty percent were high-risk patients (diabetes mellitus or coronary heart disease or PROCAM-score >20%), compared with 27% estimated by the physicians. Goal attainment rate was almost double for BP than for LDL-C in high-risk patients (62 vs. 37%). Both goals were attained by 25%. LDL-C values in phase 1 and 2 were available for 3097 high-risk patients not at LDL-C goal in phase 1; 32% of patients achieved LDL-C goal of less than 2.6 mmol/l after a mean of 17 weeks. The most successful strategies for LDL-C reduction were implemented in only 22% of the high-risk patients. Conclusion: Although patients at high cardiovascular risk were treated more intensively than low or medium risk patients, the majority remained insufficiently controlled, which is an incentive for intensified medical education. Adequate implementation of Swiss and International guidelines would expectedly contribute to improved achievement of LDL-C and BP goal values in daily practice.

Approche éducationnelle des patients à risque cardiovasculaire [Educational approach to patients with cardiovascular risk factors]

In the outpatient setting, the long-term management of cardiovascular risk factors is essential to prevent recurrent cardiovascular disease. Recent studies have shown an additional benefit of beginning cardiovascular secondary prevention during the hospital stay. Early, in-hospital initiation of proven beneficial medications, such as aspirin or blood lipid lowering drugs and therapeutic lifestyle change counseling, improves patients' long-term outcome, as long as there is continuity of care in the outpatient setting. A recent hospitalization may be a teachable moment, when patients are more likely to modify their health behaviors. The continuity of care between in-hospital medicine and the outpatient setting helps patients in the long-term management of their cardiovascular disease.

Association entre consommation d'alcool et facteurs de risque cardiovasculaire: une étude sur la population lausannoise. [Association between alcohol consumption and cardiovascular risk factors: a narrative review]

Alors que la consommation modérée d'alcool est liée à un risque plus faible de développer une maladie coronarienne, l'impact d'une consommation plus importante d'alcool sur les facteurs de risque cardiovasculaire (FRCV) et la maladie coronarienne est moins clair. Nous avons étudié l'association entre la consommation d'alcool, les FRCV et l'estimation du risque à dix ans de faire un événement cardiovasculaire dans l'étude populationnelle lausannoise CoLaus. Dans cette étude, 73% des participants consomment de l'alcool, 16% consomment de 14 à 34 unités d'alcool par semaine et 2% consomment 35 unités ou plus par semaine. Cet article montre notamment l'impact d'une consommation importante d'alcool sur les FRCVet passe en revue les liens entre la consommation d'alcool, le type de boissons et les FRCV. [Abstract] Moderate alcohol consumption has been associated with lower coronary heart disease (CHD) risk. However, the impact of higher alcohol consumption on cardiovascular risk factors (CVRFs) is conflicting. We examined the association between alcohol consumption, CVRFs and the estimated 10-year CHD risk in the population-based CoLaus study in Lausanne, Switzerland. Among 5'769 participants without cardiovascular disease, 73% of the participants were alcohol drinkers; 16% consumed 14-34 drinks/week and 2% consumed >= 35 drinks/week. This article shows the impact of high alcohol consumption on CVRFs and reviews the literature on the associations between alcohol consumption and CVRFs.

Obesity markers and estimated 10 year fatal cardiovascular risk in Switzerland

Objective: To assess the effectiveness of obesity markers to detect high (>5%) 10- year risk of fatal cardiovascular disease (CVD) as estimated using the SCORE function. Methods: Cross-sectional study including 3,047 women and 2,689 men aged 35-75 years (CoLaus study). Body fat percentage was assessed by tetrapolar bioimpedance. CVD risk was assessed using the SCORE risk function and gender and age-specific cut points for body fat were derived. The diagnostic accuracy of each obesity marker was evaluated through receiver operating characteristics (ROC) analysis. Results: Body fat presented a higher correlation with 10-year CVD risk than waist/hip ratio (WHR), waist or BMI: in men, r=0.31, 0.22, 0.19 and 0.12 and for body fat, WHR, waist and BMI, respectively; the corresponding values in women were 0.18, 0.15, 0.11 and 0.05, respectively (all p<0.05). In both genders, body fat showed the highest area under the ROC curve (AUC): in men, the AUC (and 95% confidence interval) were 76.0 (73.8 - 78.2), 67.3 (64.6 - 69.9), 65.8 (63.1 - 68.5) and 60.6 (57.9 - 63.5) for body fat, WHR, waist and BMI, respectively. In women, the corresponding values were 72.3 (69.2 - 75.3), 66.6 (63.1 - 70.2), 64.1 (60.6 - 67.6) and 58.8 (55.2 - 62.4). The use of body fat percentage criterion enabled to capture three times more subjects with high CVD risk than BMI criterion, and almost twice as much as WHR criterion.. Conclusions: Obesity defined by body fat percentage is more accurate to detect high 10-year risk of fatal CVD than obesity markers based on WHR, waist or BMI.

Seasonality of cardiovascular risk factors: an analysis including over 230 000 participants in 15 countries.

OBJECTIVE: To assess the seasonality of cardiovascular risk factors (CVRF) in a large set of population-based studies. METHODS: Cross-sectional data from 24 population-based studies from 15 countries, with a total sample size of 237 979 subjects. CVRFs included Body Mass Index (BMI) and waist circumference; systolic (SBP) and diastolic (DBP) blood pressure; total, high (HDL) and low (LDL) density lipoprotein cholesterol; triglycerides and glucose levels. Within each study, all data were adjusted for age, gender and current smoking. For blood pressure, lipids and glucose levels, further adjustments on BMI and drug treatment were performed. RESULTS: In the Northern and Southern Hemispheres, CVRFs levels tended to be higher in winter and lower in summer months. These patterns were observed for most studies. In the Northern Hemisphere, the estimated seasonal variations were 0.26 kg/m(2) for BMI, 0.6 cm for waist circumference, 2.9 mm Hg for SBP, 1.4 mm Hg for DBP, 0.02 mmol/L for triglycerides, 0.10 mmol/L for total cholesterol, 0.01 mmol/L for HDL cholesterol, 0.11 mmol/L for LDL cholesterol, and 0.07 mmol/L for glycaemia. Similar results were obtained when the analysis was restricted to studies collecting fasting blood samples. Similar seasonal variations were found for most CVRFs in the Southern Hemisphere, with the exception of waist circumference, HDL, and LDL cholesterol. CONCLUSIONS: CVRFs show a seasonal pattern characterised by higher levels in winter, and lower levels in summer. This pattern could contribute to the seasonality of CV mortality.

The PsyCoLaus study: methodology and characteristics of the sample of a population-based survey on psychiatric disorders and their association with genetic and cardiovascular risk factors.

ABSTRACT: BACKGROUND: The Psychiatric arm of the population-based CoLaus study (PsyCoLaus) is designed to: 1) establish the prevalence of threshold and subthreshold psychiatric syndromes in the 35 to 66 year-old population of the city of Lausanne (Switzerland); 2) test the validity of postulated definitions for subthreshold mood and anxiety syndromes; 3) determine the associations between psychiatric disorders, personality traits and cardiovascular diseases (CVD), 4) identify genetic variants that can modify the risk for psychiatric disorders and determine whether genetic risk factors are shared between psychiatric disorders and CVD. This paper presents the method as well as somatic and sociodemographic characteristics of the sample. METHODS: All 35 to 66 year-old persons previously selected for the population-based CoLaus survey on risk factors for CVD were asked to participate in a substudy assessing psychiatric conditions. This investigation included the Diagnostic Interview for Genetic Studies to elicit diagnostic criteria for threshold disorders according to DSM-IV and algorithmically defined subthreshold syndromes. Complementary information was gathered on potential risk and protective factors for psychiatric disorders, migraine and on the morbidity of first-degree family members, whereas the collection of DNA and plasma samples was part of the original somatic study (CoLaus). RESULTS: A total of 3,691 individuals completed the psychiatric evaluation (67% participation). The gender distribution of the sample did not differ significantly from that of the general population in the same age range. Although the youngest 5-year band of the cohort was underrepresented and the oldest 5-year band overrepresented, participants of PsyCoLaus and individuals who refused to participate revealed comparable scores on the General Health Questionnaire, a self-rating instrument completed at the somatic exam. CONCLUSIONS: Despite limitations resulting from the relatively low participation in the context of a comprehensive and time-consuming investigation, the PsyCoLaus study should significantly contribute to the current understanding of psychiatric disorders and comorbid somatic conditions by: 1) establishing the clinical relevance of specific psychiatric syndromes below the DSM-IV threshold; 2) determining comorbidity between risk factors for CVD and psychiatric disorders; 3) assessing genetic variants associated with common psychiatric disorders and 4) identifying DNA markers shared between CVD and psychiatric disorders.

Population specific and up to date cardiovascular risk charts can be efficiently obtained with record linkage of routine and observational data.

BACKGROUND: Only few countries have cohorts enabling specific and up-to-date cardiovascular disease (CVD) risk estimation. Individual risk assessment based on study samples that differ too much from the target population could jeopardize the benefit of risk charts in general practice. Our aim was to provide up-to-date and valid CVD risk estimation for a Swiss population using a novel record linkage approach. METHODS: Anonymous record linkage was used to follow-up (for mortality, until 2008) 9,853 men and women aged 25-74 years who participated in the Swiss MONICA (MONItoring of trends and determinants in CVD) study of 1983-92. The linkage success was 97.8%, loss to follow-up 1990-2000 was 4.7%. Based on the ESC SCORE methodology (Weibull regression), we used age, sex, blood pressure, smoking, and cholesterol to generate three models. We compared the 1) original SCORE model with a 2) recalibrated and a 3) new model using the Brier score (BS) and cross-validation. RESULTS: Based on the cross-validated BS, the new model (BS = 14107×10(-6)) was somewhat more appropriate for risk estimation than the original (BS = 14190×10(-6)) and the recalibrated (BS = 14172×10(-6)) model. Particularly at younger age, derived absolute risks were consistently lower than those from the original and the recalibrated model which was mainly due to a smaller impact of total cholesterol. CONCLUSION: Using record linkage of observational and routine data is an efficient procedure to obtain valid and up-to-date CVD risk estimates for a specific population.

Perception of cardiovascular risk and comparison with actual cardiovascular risk.

BACKGROUND: Current guidelines recommend treating patients according to their absolute cardiovascular disease (CVD) risk. We examined perception of CVD risk among adults and how it can be compared with actual CVD risk. METHODS: The perception of CVD risk was assessed by two questions asking about participants' 'risk to get a heart attack or a stroke over the next 10 years' using semiquantitative and quantitative answers in a population-based survey of 816 individuals aged 40-64 years in the Seychelles (African region). Actual CVD risk was calculated using a standard risk prediction score and 24% of adults aged 40-64 years had elevated risk. RESULTS: Only 59% of individuals could give an estimate of perceived CVD risk based on the semiquantitative question and 31% based on the quantitative question. Reporting a perceived CVD risk was strongly associated with high socio-economic status (SES; odds ratio = 9). Among individuals who reported a perceived CVD risk, 48% overestimated their perceived risk versus their actual risk. Reporting a high perceived CVD risk was associated with treatment for CVD risk factors, older age, low SES, and overweight. Reporting a low perceived CVD risk was associated with male sex, younger age, education, normal BMI, and leisure time exercise. CONCLUSION: Only half of the individuals could provide an estimate of their perceived CVD risk, and this perception was strongly associated with SES. Individuals under treatment perceived higher CVD risk than nontreated individuals. Further studies should determine how risk-related information can be better conveyed to individuals as a means to improve adherence to healthy lifestyles and/or treatment.