Biological Cardiovascular Risk Factors Research Articles

Autonomic Nervous System Activity and Decline as Prognostic Indicators of Cardiovascular and Cerebrovascular Events: The ‘PROOF’ Study

Background: Transversal studies have underlined the association between the decline in autonomic nervous system (ANS) activity and all-cause mortality. However, the predictive value of ANS has never been prospectively assessed in a general population-based cohort. Method: The PROOF (PROgnostic indicator OF cardiovascular and cerebrovascular events) cohort study was designed to prospectively assess the predictive value of ANS activity level in the general population, with regard to cardiovascular and cerebrovascular events, and death. This predictive power will be compared with the usual and newly discovered risk factors for the purposes of developing a risk model. Results: A prospective cohort of elderly subjects aged 65 years upon study entry were recruited from the electoral list of the city of Saint-Etienne, France. Three initial 2-year examination programs were scheduled for 7 years (2001–2007), followed by late events monitoring. At each examination, ANS activity was assessed along with clinical and biological cardiovascular risk factors, brain MRI, neuropsychological evaluation, physical activity profile, and sleep-related breathing disorders. The main study outcomes are stroke, myocardial infarction and death from any cause. A cohort consisting of 1,011 subjects aged 65.6 (0.8) years was constituted. Conclusion: Despite other selective characteristics, the associations between ANS activity and events will be applicable to other populations.

Influence of time spent on TV viewing and vigorous intensity physical activity on cardiovascular biomarkers. The Inter 99 study

Sedentary behaviour, especially TV viewing, has been identified as a possible risk factor for cardiovascular disease, whereas physical activity seems to protect against major cardiovascular risk factors: obesity, dyslipidemia and hypertension. The aim of this study was to explore the association between both time spent on TV viewing and vigorous intensity physical activity in relation to body mass index, waist circumference, waist/hip ratio, serum lipids and blood pressure. A total of 1693 men and women, 33-64 years of age, from the 3-year follow-up of a population-based intervention study, The Inter 99 study, were included in this cross-sectional design. Information on TV viewing, physical activity and other lifestyle habits was obtained by self-report questionnaire. Associations between TV viewing/physical activity and biological cardiovascular risk factors were explored by multiple linear regression analyses. Data from 835 (51%) men and 805 (49%) women were included. Mean age was 50.8 years (33.0-64.6). Men had a higher overall physical activity score than women (P<0.0001). TV viewing was significantly, positively associated with waist/hip ratio (P=0.005), body mass index (P=0.03), triglycerides (P=0.005), low density lipoprotein cholesterol (P=0.03), total cholesterol (P=0.01), systolic (P=0.05) and diastolic blood pressure (P=0.03), but not with waist circumference and high density lipoprotein cholesterol (HDL). Engaging in vigorous intensity physical activity was associated with higher HDL (P=0.0006) and lower waist circumference (P<0.0001). TV viewing and physical activity should be regarded as separate types of behaviour that relate to different cardiovascular disease risk factors.

Commuting physical activity is favourably associated with biological risk factors for cardiovascular disease

Little is known about the effects of commuting physical activity on biological cardiovascular risk factors although such knowledge may form an important basis for interventions aimed at reducing cardiovascular disease (CVD) by increasing physical activity. We examined the associations between commuting, leisure time and total physical activity and biological risk factors for CVD. Design A cross-sectional study of men and women, who participated in a health screening programme. The study population comprised persons aged 30-60 years from a population-based random sample, response rate 53% (n = 6,906). Weight, height, waist circumference and blood pressure were measured and blood samples were collected. Physical activity was assessed by a self-administered questionnaire. Time spent on commuting, leisure time and total physical activity was positively associated with high-density lipoprotein cholesterol and negatively associated with low-density lipoprotein cholesterol, triglycerides, waist circumference and body mass index. Time spent on total physical activity was negatively associated with total cholesterol and diastolic blood pressure. Among men there was no relationship between time spent on physical activity and systolic blood pressure. Time spent on commuting physical activity and total physical activity was negatively associated with systolic blood pressure among women. Commuting physical activity, independent of leisure time physical activity, was associated with a healthier level of most of the cardiovascular risk factors. An increase in commuting physical activity in the population may therefore reduce the incidence of CVD.

Associations between overall physical activity level and cardiovascular risk factors in an adult population

It is well established that physical activity level is inversely associated with cardiovascular morbidity and mortality, and with all-cause mortality. However, the dose-response relationship between physical activity and other cardiovascular disease risk factors is not fully understood. The aim of the present study was to explore the dose-response relationship between daily physical activity, as measured by a metabolic equivalent score, and BMI, waist circumference, waist hip ratio, total cholesterol, HDL, LDL, triglycerides, systolic and diastolic blood pressure. A total of 1693 men and women, 33-64 years of age, from the 3 year follow-up of a population-based intervention study, were included in this cross-sectional study. Information on physical activity and other lifestyle factors was obtained by self-report questionnaire. Associations between activity level and biological variables were explored by general linear regression. Data from 835 (51%) men and 805 (49%) women were included. Mean age was 50.8 years (33-64). A significant inverse association between average 24-hour physical activity level < or =45 METs and waist circumference (men p = 0.012, women p = 0.011), BMI (p = 0.0004), waist-hip-ratio (p = 0.002) and triglycerides (p = 0.0001) was found as well as a positive association with HDL (p = <0.0001). In those with an activity level above 45 METs there were no associations. No association was found with total cholesterol, LDL, systolic or diastolic blood pressure. This study suggests a linear dose-response relationship between activity level and certain biological cardiovascular risk factors up to a threshold of a daily 24 h MET-score of 45, which corresponds to a moderate physical activity level.

Effects of hormone replacement therapy on plasma viscosity and Doppler variations in postmenopausal non-smokers and heavy smokers

Objectives. To evaluate the effects of transdermal hormone replacement therapy (HRT) on some biological cardiovascular risk factors, specifically thromboxane B2 level and plasma viscosity. Furthermore, we investigated Doppler flow modifications at the level of the uterine, internal carotid, ophthalmic and bladder wall arteries, and evaluated whether there were significant differences, in the examined parameters, between postmenopausal women who were non-smokers and heavy smokers.Methods. Forty-three postmenopausal women (age 53.6 ± 3.3 years, mean ± standard deviation) participated in the study and were divided into two groups (Group I: n = 21, normal controls; and Group II: n = 22, heavy smokers). Patients were treated with continuous estradiol transdermal supplementation and 12-day courses of medroxyprogesterone acetate every 2 months. They were studied at baseline and after 6 months (in the estrogen-only phase of the cycle).Results. Results showed a beneficial effect of hormone substitution after 6 months of therapy. Plasma viscosity decreased significantly after 6 months of therapy both in non-smokers and heavy smokers (–18% and – 14%, respectively). Plasma levels of thromboxane B2, which were similar at baseline, underwent a dramatic reduction in both Group I and Group II (–93% and – 88%, respectively). Doppler assessment of pulsatility index at the level of the uterine, internal carotid, ophthalmic and bladder wall arteries showed a significant reduction in vascular impedance at the end of treatment in both groups. However, the treatment was significantly less beneficial, in terms of the analyzed factors, in heavy smokers.Conclusions. Cigarette smoking represents a cardiovascular risk factor that can only partially be modified by the administration of transdermal HRT.

Physical activity and biological risk factors clustering in pediatric population

Background. From a preventive point of view, it is especially important to investigate the life style risk factors connected to cardiovascular disease (CVD) biological risk factors clustering. The purposes of this study were (I) to determine in pediatric population the coexistence of biological cardiovascular disease risk factors (high blood pressure (HBP), percentage of high fat mass (%HFM), and high total cholesterol (HTC)) and (II) to study the relationship between low physical activity, a lifestyle risk factor, with those biological risk factors. Methods. This study comprised 1461 children (699 males and 762 females) aged between 8 and 15 years old. The following measurements were carried out: blood pressure, percentage of fat mass, total cholesterol (TC), and physical activity. The quartiles, adjusted for age and gender, were the criterion used to classify the subjects at risk. Odds ratios and confidence intervals at 95% were used to study HBP, HTC, and %HFM clustering in both genders. Multinomial logistic regression was used to investigate the relationship between clustering and physical activity index (PAI). Results. The findings of this study indicated that there is clustering for the biological risk factors, specially between HBP and %HFM for females. It can be observed that about half of the subjects had at least one biological risk factor. Conclusions. The results of the present study suggest that children and adolescents with higher PAI have a lower number of biological risk factors for CVD.

Transdermal hormone replacement therapy and Doppler findings in normal and overweight postmenopausal patients

The aim of this study was to evaluate the effects of transdermal hormone replacement therapy on some biological cardiovascular risk factors, specifically the thromboxane B2 levels, plasma viscosity and the lipid profile. Furthermore, we investigated the Doppler flow modifications at the level of the uterine artery, the internal carotid, the ophthalmic and the bladder wall arteries, and we finally evaluated whether there were significant differences in the examined parameters between normal and overweight postmenopausal women. Forty-five postmenopausal women (mean age ± standard deviation, 53.5 ± 3.8 years) participated in the study and were divided into two groups (27 with a body mass index of < 25 kg/m2 and 18 with a body mass index of > 25 kg/m2). Patients were treated with a continous estradiol transdermal supplement and a 12-day course of medroxyprogesterone acetate every 2 months, and were studied at baseline and after 6 months (in the estrogen-only phase of the second cycle). Our results showed a beneficial effect of hormone substitution on plasma viscosity, thromboxane B2 levels and lipid profile after 6 months of therapy and significant improvements of Doppler flow parameters in the examined vessels. Furthermore, we observed a lower impact of the treatment in overweight women. In conclusion, obesity represents an additional cardiovascular risk condition and it can only partially be modified by the administration of hormone replacement therapy.

Biological cardiovascular risk factors cluster in Danish children and adolescents: the European Youth Heart Study

Background The aim of this study was to determine whether the number of participants with multiple coronary heart disease (CHD) risk factors exceeded the number expected from a random distribution. Methods A cross-sectional study of 1020 randomly selected boys and girls, 9 and 15 years old, was conducted. Risk factors were total cholesterol, HDL-cholesterol, triglyceride, serum insulin, and blood pressure. Physical fitness was assessed from a maximal cycle test and body fat from the sum of four skinfolds. Risk factors selected in the analysis were those related to the metabolic syndrome. Results More participants than expected had four or five CHD risk factors. Four risk factors were found in 3.03 (95% confidence interval (CI): 2.24–4.10) times as many participants as expected from a random distribution and five risk factors were found in 8.70 (95% CI: 4.35–17.4) times as many participants as expected. Fifty (5.4%) had four or five risk factors and in these individuals physical fitness was 1.2 standard deviation (SD) lower and body mass index (BMI) 1.6 SD higher than mean values for the population. Conclusion Clustering of risk factors for the metabolic syndrome was found in children and adolescents. Low levels of physical fitness and raised BMI in these individuals indicate that lifestyle factors such as physical activity and diet may influence the development of these unhealthy risk profiles.

Some biological cardiovascular risk factors and diet in samples of the male population of Tallinn, Estonia in 1984/1985 and 1992/1993.

The role of diet in the development of atherosclerosis and coronary heart disease is well known from animal, clinical and epidemiological studies; the influence of dietary factors is realized through their impact on body mass, lipids and blood pressure. The aim of this investigation was to study the levels of some biological risk factors: blood pressure, total cholesterol, triglycerides and body mass, as well as nutrition, in the male population of Tallinn, the capital of Estonia, in 1984/1985 and 1992/1993 (the transition period). Two independent random samples of the male population of Tallinn, aged 30 to 54, were examined in 1984/1985 (1,890 men) and in 1992/1993 (752 men). Standard epidemiological investigation methods were used; the diet was studied by the 24 h recall method. By the time of the second survey the age-adjusted mean values of systolic and diastolic blood pressure, body mass index and triglycerides, as well as the prevalence of arterial hypertension, hypercholesterolaemia and hypertriglyceridaemia were lower than at the first survey. These data were in accordance with the dietary pattern: lower energy, animal protein, fat, saturated fatty acids, cholesterol intake and higher consumption of vegetable protein and P/S ratio at the second survey. Taking into account close relationships between many nutrients and biological risk factors found previously, changes in the diet of the population, which occurred in postsocialist Estonia in the early 1990s, could be regarded as one of the reasons for the differences in the levels of these risk factors.

Exercise and youth: Physical activity,sport involvement, and development

This article summarizes Plenary Session I, “Exercise and Youth,” at the 6th Annual Congress of the European College of Sport Science (Cologne, 24–28 July 2001). The session provided a broad overview of current knowledge and progress in the field. Using the results of cross-sectional studies, Dietrich Kurz of Germany demonstrated associations between sport activity and personal attributes of psychosocial and physical health. Using the results of a longitudinal study, Wolf-Dietrich Brettschneider found that German sport clubs in and of themselves do not have significant effects on the development of psychosocial health in young people. In a Dutch longitudinal study, Willem van Mechelen found moderate tracking of biological cardiovascular risk factors and of physical fitness from adolescence into adulthood, as well as relationships between adolescent physical activity and both adult bone health and maximal aerobic power. Reporting on findings from U.S.-American school intervention program, Tom McKenzie demonstrated the importance of social contexts, physical opportunities for sport, mental motivation for healthy lifestyles, trainer and teacher development with continuous education, and innovative, cooperative arrangements between schools and community-based agencies.

Distribution and determinants of ischaemic heart disease in an urban population. A study from the myocardial infarction register in Malmö, Sweden.

Age adjusted incidence of myocardial infarction has been found to vary substantially between the residential areas of the city of Malmö. The objective of this study was to assess the extent to which major biological risk factors and socio-economic circumstances account for the differences in incidence of and mortality from myocardial infarction. Ecological study of risk factor prevalence and incidence and mortality from myocardial infarction. Seventeen administrative areas in Malmö, Sweden. Assessment of risk factor prevalence was based on 28 466 men and women, ranging from 45 to 73 years old, who were recruited as participants in the Malmö Diet and Cancer study. Information on serum lipids was available in a random subsample of 5362 subjects. Information about socio-economic level of the residential area was based on statistics from the Malmö City Council and Statistics Sweden. Weighted least square regressions between prevalence of risk factors (i.e. smoking, hypertension, obesity, diabetes, hypercholesterolemia and hypertriglyceridemia), a myocardial infarction risk score, a socio-economic score and incidence and mortality from myocardial infarction. The risk factor prevalence and myocardial infarction incidence was highest in areas with low socio-economic level. Prevalence of smoking, obesity and hypertension was significantly associated with myocardial infarction incidence and mortality rates amongst men (all r > 0.60). Prevalence of smoking was significantly associated with incidence and mortality from myocardial infarction amongst women (r = 0.66 and r = 0.61, respectively). A myocardial infarction risk score based on four biological risk factors explained 40-60% of the intra-urban geographical variation in myocardial infarction incidence and mortality. The socio-economic score added a further 2-16% to the explained variance. In an urban population with similar access to medical care, well-known biological cardiovascular risk factors account for a substantial proportion of the intra-urban geographical variation of incidence of and mortality from myocardial infarction. The socio-economic circumstances further contribute to the intra-urban variation in disease.

Abstracts of literature

Abstracts of literature

Physical activity and 10-year mortality from cardiovascular diseases and all causes: The Zutphen Elderly Study.

Little is known about physical activity and mortality risk in the elderly. Therefore, we describe the associations between the physical activity pattern of elderly men and the mortality from cardiovascular diseases (CVDs), particularly coronary heart disease (CHD) and stroke, and all causes. Self-reported physical activity was assessed with a validated questionnaire for retired men in a population-based sample of 802 Dutch men, aged 64 to 84 years at baseline. Relative risks were estimated for 10-year mortality from CVD (199 deaths), CHD (90), stroke (47), and all causes (373) for tertiles of time spent on physical activity (reference, lowest tertile). Adjustments were made for baseline age, relevant major chronic diseases, cigarette smoking, and alcohol consumption. Mortality risks from CVD and all causes decreased with increasing physical activity (P for trend = .04) with adjusted relative risks of 0.70 (95% confidence interval, 0.48-1.01) and 0.77 (95% confidence interval, 0.59-1.00) in the highest tertile of total physical activity, respectively. Except for CHD, time spent in more intense activities (> or = 4 kcal/kg per hour) was more strongly associated with all mortality outcomes than less intense activities, but no single type of activity was particularly protective. Walking or cycling at least 3 times per week for 20 minutes (our definition of activity based on general health recommendations) was associated with reduced mortality from CVD (adjusted relative risk, 0.69; 95% confidence interval, 0.50-0.88) and all causes (relative risk, 0.71; 95% confidence interval, 0.58-0.88). Additional adjustment for biological cardiovascular risk factors did not affect the strength of any association. In a general population of elderly men, physical activity may protect against mortality from CVDs and all causes.

Anticipation of job loss or job change and cardiovascular risk factors: a study of retiring self-defense officials in Japan.

Self-defense officials in Japan are to retire at the age of early 50s. This unique situation prompted the authors to investigate whether preexisting morbid conditions cause any difficulty in finding a post-retirement job and whether anticipation of job loss or job change, as measured by the status of post-retirement job and months remaining until retirement, was related to biological cardiovascular risk factors. The subjects were 2,228 male self-defense officials who received a preretirement health examination at three Self-Defense Forces Hospitals from 1991 to 1992; the period in time remaining until retirement ranged from 1-40 months (median 12 months), and 62% had one year or less until the retirement. The defined preexisting illnesses included a wide range of chronic, non-communicable diseases. Overall, the preexisting illness was unrelated to the determination of a post-retirement job. In men having 6 months or less until retirement, however, the security of post-retirement job was less frequent when they had the preexisting illness, especially cardiovascular diseases. In 1,839 men excluding those with the preexisting illness, the period until retirement was not adversely related to obesity, blood pressure, serum lipids, serum uric acid, or glucose intolerance whether the post-retirement job had been secured or not. The findings suggest that the preexisting illness decreases the chance of obtaining a post-retirement job, but do not provide any evidence that anticipation of job loss or job change due to early retirement exerts an adverse effect on biological cardiovascular risk factors.

Are Life Stress and Social Support Related to Parity in Women?

Although an increased risk of coronary heart disease has been demonstrated among women with high gravidity/parity, the mechanism by which this association may be mediated is unclear: One possible pathway that has been suggested is that pregnancy and child rearing may result in changes in factors such as stress or lifestyle. This hypothesis was tested in a sample of 541 middle-aged women who participated in a prospective study of the effects of menopause on behavioral and biological cardiovascular risk factors. Married women generally reported less chronic stress, less perceived stress, and more structural support than did unmarried women. However, the findings in this study indicated no consistent relationship between parity and stress or parity and social support in this group of middle-aged women. Only unmarried women with more children reported a higher number of life events than did women with fewer children.

Habitual physical activity and cardiovascular risk factors

The relationships between different levels of participation in physical activity and biological indices of cardiovascular risk were examined in a sample of 6814 male and female adults who took part in a national risk factor prevalence survey. Participation in physical activity was classified as aerobic (14.6% of total), moderate (53.6%) or inactive (31.8%). Bivariate analyses found significant associations between level of exercise participation and diastolic blood pressures in men, but not in women; significant associations were found between reported physical activity and systolic blood pressure, total serum cholesterol, high-density lipoprotein (HDL) cholesterol, HDL/total cholesterol ratio and triglycerides for both men and women. Further analyses were controlled for age, education, and the survey site, which were potential confounders of the association between physical activity and other coronary heart disease risk factors. After adjustment, significant associations remained between levels of exercise participation and HDL cholesterol level, HDL/total cholesterol ratio and serum triglyceride levels for both sexes. In women, there was also a significant relationship between activity level and body mass index. In addition, for men only, there was a significant inverse relationship between physical activity and total cholesterol, and, for older men, between physical activity and systolic blood pressure. It is well recognised that physical activity has an independent effect on reducing the risk of coronary heart disease. The results of this study suggest that there may be small supplementary effects mediated through the relationship between exercise and other biological cardiovascular risk factors.

Habitual physical activity and cardiovascular risk factors

The relationships between different levels of participation in physical activity and biological indices of cardiovascular risk were examined in a sample of 6814 male and female adults who took part in a national risk factor prevalence survey. Participation in physical activity was classified as "aerobic" (14.6% of total), "moderate" (53.6%) or "inactive" (31.8%). Bivariate analyses found significant associations between level of exercise participation and diastolic blood pressures in men, but not in women; significant associations were found between reported physical activity and systolic blood pressure, total serum cholesterol, high-density lipoprotein (HDL) cholesterol, HDL/total cholesterol ratio and triglycerides for both men and women. Further analyses were controlled for age, education, and the survey site, which were potential confounders of the association between physical activity and other coronary heart disease risk factors. After adjustment, significant associations remained between levels of exercise participation and HDL cholesterol level, HDL/total cholesterol ratio and serum triglyceride levels for both sexes. In women, there was also a significant relationship between activity level and body mass index. In addition, for men only, there was a significant inverse relationship between physical activity and total cholesterol, and, for older men, between physical activity and systolic blood pressure. It is well recognised that physical activity has an independent effect on reducing the risk of coronary heart disease. The results of this study suggest that there may be small supplementary effects mediated through the relationship between exercise and other biological cardiovascular risk factors.