Multiple cardiovascular disease risk factors in Canadian adults. Canadian Heart Health Surveys Research Group.

OBJECTIVE: To estimate the prevalence and distribution of the coexistence of major cardiovascular disease (CVD) risk factors among Canadian adults. DESIGN: Population-based cross-sectional surveys. SETTING: Nine Canadian provinces, from 1986 to 1990. PARTICIPANTS: A probability sample of 26,293 men and women, aged 18 to 74 years, was selected from provincial health insurance registries. For 20,582 of these participants, at least two blood pressure (BP) measurements were taken using a standardized technique. At a subsequent visit to a clinic, two additional BP readings, anthropometric measurements and a blood specimen for plasma lipid analysis were obtained. OUTCOME MEASURES: The percentage distribution of subjects by number of major risk factors (smoking, high BP and elevated blood cholesterol level) and by concomitant factors (body mass index [BMI], ratio of waist to hip circumference [WHR], physical activity, diabetes, awareness of CVD risk factors and education). MAIN RESULTS: Sixty-four percent of men and 63% of women had one or more of the major risk factors. Prevalence increased with age to reach 80% in men and 89% in women aged 65 to 74 years. Prevalence of two or three risk factors was highest among men in the 45-54 age group (34%) and in women in the 65-74 age group (37%). The most common associations were between smoking and high blood cholesterol level (10%) and between high BP and high blood cholesterol level (8%). Prevalence of high BP and elevated blood cholesterol, alone or in combination, increased with BMI and WHR. Smoking, elevated blood cholesterol, BMI and prevalence of one or more risk factors increased with lower level of education. Less than 48% of participants mentioned any single major risk factor as a cause of heart disease. Awareness was lowest in the group with fewest years of education. CONCLUSION: The findings of this study call for an approach to reduce CVD that stresses collaboration of the different health sectors to reach both the population as a whole and the individuals at high risk.     

Obesity and its relation to cardiovascular disease risk factors in Canadian adults. Canadian Heart Health Surveys Research Group.

OBJECTIVE: To describe the distribution of weight and abdominal obesity among Canadian adults and to determine the association of obesity with other risk factors for cardiovascular disease. DESIGN: Population-based cross-sectional surveys. Survey nurses administered a standard questionnaire and recorded two blood pressure measurements during a home visit. At a subsequent visit to a survey clinic two further blood pressure readings were made, anthropometric measurements recorded and a blood specimen taken for plasma lipid determination. SETTING: Nine Canadian provinces, from 1986 to 1990. PARTICIPANTS: A probability sample of 26,293 men and women aged 18 to 74 years was selected from the health insurance registration files of each province. Anthropometry was performed on 17,858 subjects. OUTCOME MEASURES: Body mass index (BMI), ratio of waist to hip circumference (WHR), mean plasma lipid levels, prevalence of high blood pressure (diastolic greater than or equal to 90 mm Hg or patient on treatment) and self-reported diabetes mellitus. MAIN RESULTS: The prevalence of obesity (BMI greater than or equal to 27) increased with age and was greater in men (35%) than in women (27%). Abdominal obesity was likewise higher in men and increased with both age and BMI. The prevalence of high blood pressure was greater in those with higher BMI, especially in those with a high WHR. Although total plasma cholesterol levels increased only modestly with BMI, levels of low density lipoprotein (LDL) cholesterol and triglycerides and the ratio of total cholesterol to high density lipoprotein (HDL) cholesterol increased steadily, while HDL-cholesterol decreased consistently with increasing BMI. High total cholesterol levels (greater than or equal to 5.2 mmol/L) were more prevalent among people with high BMI, especially those with a high WHR. The prevalence of diabetes increased with BMI among those 35 years or older, especially those with abdominal obesity. About half of men and two-thirds of women who were obese were trying to lose weight. CONCLUSION: Obesity remains common among Canadian adults. There is a need for broad-based programs that facilitate healthy eating and activity patterns for all age groups. Health professionals should incorporate measurement of BMI and WHR into their routine examinations of patients to enhance their evaluation of health risk.     

Canadian heart health surveys: a profile of cardiovascular risk. Survey methods and data analysis. Canadian Heart Health Surveys Research Group.

OBJECTIVE: To describe the methods used in nine provincial surveys carried out as part of the Canadian Heart Health Initiative. DESIGN: Population-based cross-sectional surveys, following a core standardized protocol, implemented by provincial departments of health in collaboration with Health and Welfare Canada. Data were obtained through a home interview and a clinic visit. A standard manual of field operations and standardized training procedures were used in all provinces. SETTING: Nine Canadian provinces during the period 1986 to 1990. PARTICIPANTS: A probability sample of 26,293 men and women aged 18 to 74 years was selected from the health insurance registries in each province. Over 30% of the participants had post-secondary education. About 50% were 18 to 34 years old. OUTCOME MEASURES: Data on sociodemographic characteristics, hypertensive and diabetic status, knowledge and awareness of the causes and consequences of cardiovascular disease and two blood pressure measurements were obtained in a home interview. During a clinic visit, data were collected on height, weight (waist and hip circumferences in four provinces), two blood pressure measures and a blood sample. Total plasma cholesterol, triglycerides and high- and low-density lipoprotein cholesterol were measured in the Lipid Research Laboratory, University of Toronto and St. Michael''s Hospital. MAIN RESULTS: Of the subjects invited to participate in the survey, 78% were interviewed, 69% attended the clinic and 64% provided a fasting specimen (8 hours or more). The response rates were slightly lower for men aged 18 to 34, for women aged 65 to 74 and for those with fewer years of education. Data from the provincial surveys (Ontario will complete the survey in 1992) are being compiled in the Canadian Heart Health Database. CONCLUSION: The process followed in the implementation of the provincial heart health surveys is a model of how provincial departments of health may carry out epidemiologic investigations in support of their mandate. The approach illustrates how a country-wide database can be built through partnerships among different levels of government. The use of community health nurses was instrumental in the efficient implementation of the surveys and in the realization of the relatively high rates of response attained.     

Prevalence,control and awareness of high blood pressure among Canadian adults. Canadian Heart Health Surveys Research Group.

OBJECTIVE: To estimate the prevalence and distribution of elevated blood pressure (BP) among Canadian adults and to determine the level of control, treatment, awareness and prevalence of other risk factors among adults with high BP. DESIGN: Population-based cross-sectional surveys. SETTING: Nine Canadian provinces, from 1986 to 1990. PARTICIPANTS: A probability sample of 26,293 men and women aged 18 to 74 years was selected from the health insurance registers in each province. For 20,582 subjects, BP was measured at least twice. Nurses administered a standard questionnaire and recorded two BP measurements using a standardized technique. Two further BP readings, anthropometric measurements and a blood specimen for lipid analysis were obtained from those subjects who attended a clinic. OUTCOME MEASURES: Mean values of systolic and diastolic BP, prevalence of elevated BP using different criteria, and prevalence of smoking, elevated blood cholesterol, body mass index, physical activity and presence of diabetes by high BP status are reported. MAIN RESULTS: Sixteen percent of men and 13% of women had diastolic BP of 90 mm Hg or greater or were on treatment (or both). About 26% of these subjects were unaware of their hypertension, 42% were being treated and their condition controlled, 16% were treated and not controlled, and 16% were neither treated nor controlled. Use of non-pharmacologic treatment of high BP with or without medication was low (22%). Hypertensive subjects showed a higher prevalence of elevated total cholesterol, high body mass index, diabetes and sedentary lifestyle than normotensive subjects. Most people with elevated BP were in the 90 to 95 mm Hg range for diastolic pressure and 140 to 160 mm Hg range for systolic pressure. Prevalence of high isolated systolic BP sharply increased in men (40%) and women (49%) 65 to 74 years old. CONCLUSIONS: The relatively low level of control of elevated BP calls for population and individual strategies, stressing a non-pharmacologic approach and addressing isolated systolic hypertension in the elderly.     

Plasma lipids and lipoproteins and the prevalence of risk for coronary heart disease in Canadian adults. Canadian Heart Health Surveys Research Group.

OBJECTIVE: To report population reference values for blood lipids, to determine the prevalence of lipid risk factors and to assess their association with other risk factors. DESIGN: Population-based cross-sectional surveys. Survey participants were interviewed at home and provided a blood sample at a clinic. All blood lipid analyses were done in the Lipid Research Laboratory, University of Toronto. The laboratory is standardized in the National Heart, Lung Blood Institute-Centres for Disease Control Standardization Program. SETTING: Nine Canadian provinces, from 1986 to 1990. PARTICIPANTS: A probability sample of 26,293 men and women aged 18 to 74 was selected from the health insurance registers for each province. Blood samples were obtained from 16,924 participants who had fasted 8 hours or more. OUTCOME MEASURES: Concentration of total plasma cholesterol, triglycerides and high density lipoprotein (HDL) and low density lipoprotein (LDL) cholesterol in blood samples from fasting participants. MAIN RESULTS: Of the study population, 46% had total plasma cholesterol levels above 5.2 mmol/L, 15% had LDL-cholesterol levels above 4.1 mmol/L, 15% had triglyceride levels above 2.3 mmol/L and 8% had HDL-cholesterol levels below 0.9 mmol/L. Total plasma cholesterol, LDL-cholesterol and triglyceride levels rose with age in men to a maximum in the 45-54 age group; in women there was little change with age up to ages 45 to 54, at which time the level of each of these lipids increased appreciably. The age-standardized prevalence of obesity was positively associated with elevation of total plasma cholesterol. CONCLUSION: The results suggest the need for a multifactorial approach in health promotion efforts to lower blood cholesterol levels and reduce other risk factors in the population. A considerable number of adults were found to be at risk at all ages in both sexes. In the short term, men aged 34 and older and women aged 45 and older might benefit most from prevention programs.     

Candidemia at selected Canadian sites: results from the Fungal Disease Registry, 1992-1994

BACKGROUND: Candida species are important bloodstream pathogens that are being isolated with increasing frequency. Despite the availability of effective antifungal therapy, the mortality rate associated with Candida infection remains high. With the objective of describing the epidemiology of candidemia, the Canadian Infectious Disease Society conducted a study of candidemia in Canada. METHODS: Fourteen medical centres across Canada identified all patients with candidemia from March 1992 to February 1994 through blood culture surveillance for Candida spp. Patient-related data for invasive fungal infection were compiled retrospectively by chart review using a standardized data-recording form developed for the Fungal Disease Registry of the Canadian Infectious Disease Society. Cases of Candidemia were studied in relation to underlying medical conditions, predisposing factors, concurrent infection, antimicrobial agents, antifungal treatment and deaths. RESULTS: In total, 415 cases of candidemia were identified, 48 (11.6%) in children and 367 (88.4%) in adults. The causative pathogens were C. albicans in 286 cases (68.9%), C. parapsilosis in 43 (10.4%), C. glabrata in 34 (8.2%), C. tropicalis in 27 (6.5%) and other Candida species in 18 (4.3%); polymicrobial candidemia occurred in 7 cases (1.7%). The overall mortality rate was 46%, and the rate of deaths clinically related to candidemia was 19%. However, only 13 (27%) of the children died. A univariate analysis indicated that significant risk factors for death were age greater than 60 years, therapy for concomitant bacterial infection, stay in an intensive care unit, concurrent malignant disease, cytotoxic chemotherapy and granulocytopenia, although only age and stay in an intensive care unit emerged as significant risk factors in the multivariate analysis. After adjustment for other predictors of death, only infection with C. parapsilosis was associated with a lower mortality rate than infection with C. albicans. Treatment was given in 352 (84.8%) of cases. Amphotericin B was the preferred agent in 244 cases (69.3% of those treated); fluconazole was used in 101 cases (28.7%) and ketoconazole in 5 cases (1.4%). INTERPRETATION: Candidemia in Canada is caused predominantly by C. albicans. The mortality rate associated with candidemia is high, but it varies with the species of Candida and is lower in children than in adults. Age greater than 60 years and stay in an intensive care unit were the most significant risk factors for overall mortality.     

Changes in cardiovascular disease risk factors from age 9 to 19 and the influence of television viewing

Objective:

The purpose of this study was to determine if time spent watching television is associated with changes in cardiovascular disease (CVD) risk factors from age 9 to 19.

Design and Methods:

Participants were girls enrolled in the NHLBI Growth and Health Study (n = 1,702), and CVD risk factors were measured at ages 10, 12, 14, 16, and 19. Longitudinal quantile regression was used to determine if television viewing was associated with changes in CVD risk factors over time at the 10th, 25th, 50th, 75th, and 90th percentiles of the CVD risk factors.

Results:

In black girls, television viewing (h/wk) was positively associated with sum of skinfolds (mm) at the 75th (0.22, 99% CI, 0.06‐0.38) and 90th percentiles (0.21, 99% CI, 0.05‐0.36), but not at the 10th, 25th, or 50th percentiles. In white girls, television viewing (h/wk) was positively associated with sum of skinfolds (mm) with the strength of the associations progressively stronger toward the upper tail of the skinfold distribution, adjusting for physical activity and other covariates (10th percentile: 0.08, 99% CI, 0.03‐0.13; 90th percentile: 0.42, 99% CI, 0.24‐0.59). All associations were adjusted for physical activity, dietary factors, sleep, and maturation. No associations were observed between television viewing and changes in systolic blood pressure, triglycerides, or cholesterol levels in black or white girls.

Conclusion:

Girls who spent more time watching television had greater increases in sum of skinfolds from age 9 to 19, independent of physical activity levels and other covariates. The associations observed were stronger at the upper tail of the skinfold distribution.     

Prevalence, risk factors and rheological profile of arterial vascular disease; first results of the Aachen study

During a prospective cohort-study of several year's duration the results of a survey regarding prevalence of arterial occlusive disease, as well as classical risk factors and rheological profile of patients suffering from vascular disease were examined. 364 patients out of a total of 2,498 individuals suffered from vascular disease. 168 (6.7%) had cardiovascular, 151 (6.0%) cerebrovascular and 109 (4.4%) peripheral vascular disease. Compared to to healthy individuals, the patients showed a significant accumulation of classical risk factors (elevated cholesterol and triglyceride values, decreased HDL-cholesterol concentration, obesity, smoking, high blood pressure, gout or diabetes mellitus). Only 30.2% of the healthy controls presented two or more risk factors, whereas the angiological patients showed two or more risk factors in 71.9%. Rheological parameters measured in the survey were: Plasma viscosity, erythrocyte and platelet aggregation, erythrocyte rigidity and hematocrit. Only 14.2% of the healthy individuals had two or more rheological parameters exceeding the 1-s range, whereas 56.6% of the patients showed two or more elevated rheological parameters.     

Prevalence of cardiovascular disease risk factors by habitat: a study on adult Asian Indians in West Bengal, India

The present community based cross-sectional study was aimed to investigate whether or not increasing prevalence of cardiovascular disease (CVD) risk factors in adult Asian Indian population are associated with increasing urbanization. The 'urban group' was comprised of 224 individuals including 122 males and 102 females being inhabitants of Kolkata (erstwhile Calcutta) under the Kolkata Metropolitan Development Authority (KMDA) area. The 'rural group' comprised 224 individuals including 135 males and 89 females and was living in a village council located about 80 kilometers from Kolkata. Therefore, a total of 448 adult (> or = 30 years) individuals (257 males and 191 females) participated in the study. Anthropometric measures, lipids profiles, fasting blood glucose and blood pressure measures were taken from participants. Obesity and body composition measures were subsequently calculated from the anthropometric measures. Accepted cut-offs were used to define metabolic syndrome (MS), lipids abnormalities, increased adiposity and high blood pressure in the study. It was found that 58.7% participants were engaged in sedentary work which includes 60.7% males and 56% females. It was further observed that the prevalence of high blood pressure was as high as 70.6% in urban females compared to 55.1% in rural females. However, the prevalence of low HDLc was remarkably high in females ofboth rural and urban areas. The prevalence ofMS was significantly higher in urban females (57.8%) than in their rural counterparts (34.8%). It seems reasonable to argue that people with changing lifestyles due to growing urbanization are associated with adverse CVD risk factors irrespective of their habitat (rural vs. urban). This in turn warranted a comprehensive risk stratification protocol at the national level for the effective management of CVD risk factors in this part of the world.     

Sex differences in risk factors for cardiovascular disease: the PERU MIGRANT study

Introduction

Although men and women have similar risk factors for cardiovascular disease, many social behaviors in developing countries differ by sex. Rural-to-urban migrants have different cardiovascular risk profiles than rural or urban dwellers. The objective of this study was to evaluate the sex differences with specific cardiovascular risk factors in rural-to-urban migrants.

Methods and Results

We used the rural-to-urban migrant group of the PERU MIGRANT cross-sectional study to investigate the sex differences in specific cardiovascular risk factors: obesity, hypertension, metabolic syndrome, as well as exposures of socioeconomic status, acculturation surrogates and behavioral characteristics. Logistic regression analysis was used to characterize strength of association between sex and our outcomes adjusting for potential confounders. The sample of migrants was 589 (mean age 46.5 years) and 52.4% were female. In the adjusted models, women were more likely to be obese (OR=5.97; 95%CI: 3.21–11) and have metabolic syndrome (OR=2.22; 95%CI: 1.39–3.55) than men, explaining the greatest variability for obesity and metabolic syndrome but not for hypertension.

Conclusions

Our results suggest that interventions for CVD in Peru should be sex-specific and address the unique health needs of migrant populations living in urban shantytowns since the risk factors for obesity and metabolic syndrome differ between males and females.     

Relation of serum calcium concentration to metabolic risk factors for cardiovascular disease.

Data from a health screening survey with over 18,000 adult participants were used to determine the relations between serum calcium concentration and the cardiovascular risk factors hypertension, hyperglycaemia, and hyperlipidaemia. Blood pressure and serum glucose and cholesterol concentrations were all positively related to each other independent of age, sex, kidney function, and obesity. Similar relations between the risk factors were found in subjects with hypertension or hyperglycaemia independent of the degree of overweight. These results suggested that there might be a metabolic syndrome of cardiovascular risk factors. Serum calcium concentration was positively related to systolic and diastolic blood pressures and serum glucose and cholesterol concentrations. Thus a common feature in the syndrome is an increased serum calcium concentration. The relations between serum calcium concentrations and the cardiovascular risk factors were not limited to the upper parts of the distribution, being seen over a wide range. Changes in calcium metabolism seem to be related to a metabolic syndrome of hypertension, impaired glucose tolerance, and hyperlipidaemia.     

Genetic determinants of risk factors for cardiovascular disease in a population from rural Brazil

We investigate the heritability of and pleiotropic relationships among triglycerides and cholesterol lipoproteins that have long been considered traditional risk factors for cardiovascular disease. Quantitative lipid and lipoprotein phenotypes were determined for a cross-sectional sample of a community in Jequitinhonha valley in northern Minas Gerais state, Brazil. The sample consisted primarily of subsistence farmers. Two hundred sixty-nine individuals (128 males and 141 females), ages 18-88 years, were sampled. Eighty-eight percent (n = 252) of the individuals belonged to a single pedigree, which was highly informative for genetic analysis. Data on anthropometrics, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol, and triglycerides were available for each study participant. Extended pedigrees were constructed using the pedigree-based data management software PedSys. Univariate and bivariate variance-components analyses, adjusted by sex and age, were performed using the SOLAR software package. Heritability estimates of lipids and lipoproteins ranged from 29% to 45% (p < 0.008). The highest heritability estimated was for HDL-C (h2 = 44.8%, p < 0.0001), and this was the only trait that exhibited a significant household effect (c2 = 25%). Strong positive genetic correlations were found between triglycerides and very low density lipoprotein (VLDL) (rhog = 0.998) and between total cholesterol and LDL-C (rhog = 0.948). Significant genetic correlations were also found between triglycerides and LDL-C, between total cholesterol and VLDL, and between total cholesterol and LDL-C and VLDL, and finally between LDL and VLDL. There was a significant negative environmental correlation between triglycerides and HDL-C (rhoe = -0.406).     

Job strain, job insecurity, and incident cardiovascular disease in the Women's Health Study: results from a 10-year prospective study

Objectives

Research about work-related stressors and cardiovascular disease (CVD) has produced mixed findings. Moreover, a paucity of data exists regarding the long-term associations between job strain and job insecurity and CVD among women.

Methods

We used Cox proportional hazard models to examine the relationship between job strain, job insecurity, and incident CVD over 10 years of follow-up among 22,086 participants in the Women’s Health Study (mean age 57±5 years).

Results

During 10 years of follow-up there were 170 myocardial infarctions (MI), 163 ischemic strokes, 440 coronary revascularizations, and 52 CVD deaths. In models adjusted for age, race, education, and income, women with high job strain (high demand, low control) were 38% more likely to experience a CVD event than their counterparts who reported low job strain (low demand, high control; Rate Ratio (RR) = 1.38, 95% Confidence Interval (CI) = 1.08–1.77), and women with active jobs (high demand, high control) were 38% more likely to experience a CVD event relative to women who reported low job strain (95% CI = 1.07–1.77). Outcome-specific analyses revealed that high job strain predicted non-fatal myocardial infarction (RR = 1.67, CI = 1.04–2.70), and coronary revascularization (RR = 1.41, CI = 1.05–1.90). No evidence of an association between job insecurity and long-term CVD risk was observed.

Conclusion

High strain and active jobs, but not job insecurity, were related to increased CVD risk among women. Both job strain and job insecurity were significantly related to CVD risk factors. With the increase of women in the workforce, these data emphasize the importance of addressing job strain in CVD prevention efforts among working women.     

An IGF-I promoter polymorphism modifies the relationships between birth weight and risk factors for cardiovascular disease and diabetes at age 36

BACKGROUND: Biochemical testing for pheochromocytoma by measurement of fractionated plasma metanephrines is limited by false positive rates of up to 18% in people without known genetic predisposition to the disease. The plasma normetanephrine fraction is responsible for most false positives and plasma normetanephrine increases with age. The objective of this study was to determine if we could improve the specificity of fractionated plasma measurements, by statistically adjusting for age. METHODS: An age-adjusted metanephrine score was derived using logistic regression from 343 subjects (including 33 people with pheochromocytoma) who underwent fractionated plasma metanephrine measurements as part of investigations for suspected pheochromocytoma at Mayo Clinic Rochester (derivation set). The performance of the age-adjusted score was validated in a dataset of 158 subjects (including patients 23 with pheochromocytoma) that underwent measurements of fractionated plasma metanephrines at Mayo Clinic the following year (validation dataset). None of the participants in the validation dataset had known genetic predisposition to pheochromocytoma. RESULTS: The sensitivity of the age-adjusted metanephrine score was the same as that of traditional interpretation of fractionated plasma metanephrine measurements, yielding a sensitivity of 100% (23/23, 95% confidence interval [CI] 85.7%, 100%). However, the false positive rate with traditional interpretation of fractionated plasma metanephrine measurements was 16.3% (22/135, 95% CI, 11.0%, 23.4%) and that of the age-adjusted score was significantly lower at 3.0% (4/135, 95% CI, 1.2%, 7.4%) (p < 0.001 using McNemar's test). CONCLUSION: An adjustment for age in the interpretation of results of fractionated plasma metanephrines may significantly decrease false positives when using this test to exclude sporadic pheochromocytoma. Such improvements in false positive rate may result in savings of expenditures related to confirmatory imaging.