Clustering of cardiovascular risk factors. time trends during 28 years.

OBJECTIVES: To assess the development in frequency and clustering of hypertension, hypercholesterolaemia, high body mass index (BMI), physical inactivity and tobacco smoking in the period 1964-1992, and to evaluate any sex and age differences. DESIGN: Five cross-sectional investigations on cardiovascular risk factors performed in 1964, 1978, 1982-1984, 1986-1987 and 1991-1992 comprising random samples in a suburban area of Copenhagen, Denmark. Physical activity during leisure time and smoking habits were assessed by self-administered questionnaire. Blood pressure, weight, height and serum total cholesterol were measured according to WHO standards. RESULTS: A total of 8644 persons aged 30, 40, 50 and 60 years participated with an equal number of men and women. Women had fewer risk factors than men and younger persons had fewer risk factors than older persons. In the period 1964-1992 there was a decreasing number of risk factors. The 50 year olds show a sex difference in the period 1982-1992, whereas there was no sex difference among the 60 year olds. Tobacco smoking was the most common risk factor. BMI > 27.5 has become more and more frequent throughout the period, especially in men. The BMI has conquered third place in all age groups. The association of BMI > 27.5 and sedentary leisure time physical activity has become the most frequent. CONCLUSION: Clustering among risk factors decreased over time in both sexes. The association of elevated BMI and sedentary leisure time activity may contribute to the rising frequency of chronic disease such as diabetes mellitus and cardiovascular disease.

Secular trends in acute myocardial infarction in relation to physical activity in the general Danish population.

Secular trends in AMI rates were analyzed in relation to physical activity levels. The population attributable risk of physical inactivity was calculated. Participants were randomly selected subjects from a suburb of Copenhagen, Denmark, screened during the years 1964-1991. Occupational physical activity and in leisure time were assessed 1964, 1974, 1976, 1982, 1987 and 1991 by self-administered questionnaire along with smoking habits and alcohol consumption. Blood pressure, weight, height and serum lipids were measured according to WHO-standards. Mortality data were obtained from death certificates, from hospital records or autopsies. Acute myocardial infarctions (AMI) 1964-1994 were included. 13.925 men and women aged 30, 40, 50 and 60 years, were drawn as random samples from a background population of 300.000 inhabitants. A cohort born in 1914 was examined in 1964 and 1974, a cohort born in 1936, was examined in 1976 and 1987; Monica (Monitoring trends and determinants in cardiovascular diseases) I cohort were examined in 1982 and 1987; MONICA II in 1986, and MONICA III in 1991. Mean physical activity level at leisure adjusted for age and sex increased over time (P < 0001). 25% of the men were sedentary, and more women reported a sedentary lifestyle than men. The overall trend was from 1964 to 1992 a decline in physical activity at work (P < 0001) in both gender and all age groups. The difference in AMI incidence rates between leisure time physical activity (LTPA) levels increased over time. No change was found in AMI rates comparing sedentary in different time periods. A remarkable decrease over time in the AMI incidence rate was found in physically active during leisure time. Population attributable risk (PAR) exceeded 40% in both genders in the late 1980s. In conclusion the difference in AMI rates between LTPA subgroups has increased over time. The low AMI rates observed among the most physically active reveal a substantial potential for the prevention of AMI through physical activity. A population attributable risk of more than 40% for physical inactivity suggests a potential for primary prevention through increased physical activity.

[Trends in selected biological risk factors of cardiovascular diseases in the Danish MONICA population 1982-1992]. / Udviklingen i udvalgte biologiske risikofaktorer for kardiovaskulaere sygdomme i den danske MONICA-population 1982-1992.

INTRODUCTION: The incidence rate of a first myocardial infarction declined 3-5% annually in the Danish WHO MONICA population in the period from 1982 to 1991. The aim of this study was to investigate whether levels of the most commonly considered biological traits associated with cardiovascular risk have changed in the Danish MONICA population during this period. METHOD: Data from 6,695 men and women of 30, 40, 50 and 60 years of age, examined in the Danish WHO MONICA surveys in 1982-1984, 1986-1987, and 1991-1992, were analysed to estimate temporal trends in body height and weight, blood pressure, and serum total, HDL, and LDL cholesterol, and triglyceride. RESULTS: Body height increased by 0.1% per year and the body mass index by 0.4% per year in women. The diastolic blood pressure increased 0.4% per year in women and 0.6% per year in 60-year-old men. HDL cholesterol declined 0.4% per year. Body mass indices in men, diastolic blood pressures in men < 60 years of age, systolic blood pressures, total and LDL cholesterol and triglyceride did not change. DISCUSSION: The levels of biological risk factors in the Danish WHO MONICA study population did not show trends during the 1980s that contribute to explain the declining incidence of myocardial infarction in the population.

Trends in selected biological risk factors for cardiovascular diseases in the Danish MONICA population, 1982-1992.

Data from 6695 men and women of ages 30, 40, 50, and 60 years, examined in the Danish WHO MONICA surveys in 1982-84, in 1986-87, and in 1991-92, were analyzed to estimate secular trends in body height and weight, blood pressure, and serum total, HDL-, and LDL-cholesterol, and triglyceride. Body height increased 0.1% per year, and body mass index increased 0.4% per year in women. Diastolic blood pressure increased 0.4% per year in women and 0.6% per year in 60-year-old men. HDL cholesterol declined 0.4% per year. Body mass indices in men, diastolic blood pressures in men <60 years of age, systolic blood pressures, total- and LDL cholesterol and triglyceride did not change. The levels of biological risk factors in the Danish WHO MONICA study population did not show trends during the 1980s that help explain the declining incidence of myocardial infarction in the population.

Tissue-type plasminogen activator and C-reactive protein in acute coronary heart disease. A nested case-control study.

OBJECTIVES: To study the importance of inflammation and fibrinolysis for evolution of ischaemic heart disease in a cohort of initially healthy subjects. DESIGN: Nested case-control study. Follow-up periods 7-15 years. SUBJECTS: Included in the study were 133 cases with coronary heart disease and 258 controls. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Subjects with ischaemic heart disease identified in 1991 by the Danish National Hospital Register. Protein concentration of C-reactive protein (CRP) and tissue-type plasminogen activator (t-PA) were measured with ELISA methods in stored serum samples. RESULTS: CRP and t-PA concentrations were both significantly higher in cases than in controls (P < 0.001 and P < 0. 001). This difference between cases and controls for CRP and t-PA was present in both men (CRP: P = 0.022; t-PA: P = 0.001) and women (CRP: P = 0.013; t-PA: P = 0.005) and it was present in both the 7-9 years follow-up cohort (CRP: P = 0.014; t-PA: P = 0.001) and the 15 years follow-up cohort (CRP: P = 0.027; t-PA: P = 0.012). The best predictor of CRP was t-PA, whilst the best predictor of t-PA was triglycerides. In a logistic regression analysis model, t-PA still came out as independent predictor of coronary heart disease, whilst such a significance disappeared for CRP. With the use of ROC curves we determined that AUC for t-PA was 0.62, and for CRP 0.59, indicating that none of these two analytes has a high prognostic power in predicting future coronary events in an initially healthy population. CONCLUSION: We conclude that moderate increases in serum concentrations of CRP and t-PA are present for up to 15 years before the presence of clinical overt coronary heart disease; that a low-grade inflammation is determined by other risk factors and that t-PA is an independent risk factor for evolution of coronary heart disease.

Trends in smoking prevalence in Danish adults, 1964-1994. The influence of gender, age, and education.

BACKGROUND: Studies of time trends in smoking prevalence provide a better understanding of the determinants of smoking. The present study analyses changes over time in the prevalence of smoking and heavy smoking in relation to sex, age, and education. METHODS: Data on smoking behaviour were collected by questionnaire in random samples of the general population in the area of Copenhagen. The database used included 71,842 measurements of smoking behaviour for 32,156 subjects aged 30 years or more, who had been examined at intervals between 1964 and 1994. In bi- and multivariate analyses the effects of sex, age, education, time period, and study group on the prevalence of smoking and of heavy smoking were assessed. RESULTS: Smoking was least prevalent in women, in the oldest age group (more than 70 years), and among those with 8 years or more of school education. During the study period (from 1964/74 to 1990/94), the prevalence of smoking decreased from 72% to 54% in men and from 52% to 46% in women. In both men and women this decrease was smallest in the least educated (less than 8 years of school education). Heavy smoking was also least prevalent in women, in the oldest age group, and among the well educated. During the study period, the unadjusted prevalence of heavy smoking decreased from 52% to 38% in men, while it increased from 17% to 21% in women. The multivariate analysis showed that the time trend for heavy smoking only depended on sex, while educational attainment and age had no impact on the trend. CONCLUSION: During the last 30 years the prevalence of smoking has decreased in Denmark. The decrease has been smallest in women, and among the least educated, and the increasing trend in the prevalence of heavy smoking in women is a cause for concern.

Secular trends in blood pressure levels in Denmark 1964-1991.

BACKGROUND: Hypertension is an essential risk factor for development of cardiovascular diseases. Prospective studies show a reduction in risk of myocardial infarction with reduction of blood pressure. In Denmark there was a decrease in ischaemic heart disease mortality during the period (1968-1992) with around 34% in 30-65 year old men and 30% in women. OBJECTIVE: To assess the changes in casual blood pressure between 1964 and 1991 in seven cross-sectional population studies. SETTING: Centre of Preventive Medicine, University of Copenhagen, DK-2600 Glostrup. POPULATION: 10359 subjects, equal numbers of men and women, age exactly 30, 40, 50 and 60 years drawn as random samples from a background population of 300000 inhabitants and surveyed in 1964-1974 and five cross-sectional studies 1976, 1978, 1982-1984, 1986-1987 and 1991. METHODS: Blood pressure was measured according to WHO criteria by one technician in each survey. Alcohol consumption and physical activity were measured by a self-administered questionnaire. The weight and height were measured by standardized methods. Data on mortality from ischaemic heart disease were obtained from death certificates recorded by the National Board of Health. RESULTS: Blood pressure increased with increasing age in both genders and was significantly higher in men than in women. Median blood pressure in 50 year old men in 1964 was 135/85 mmHg and in 1991 it was 123/79, whereas in women in 1964 it was 140/85, against 119/74 in 1991. The prevalence of hypertensives among 30 and 40 year olds declined throughout the period. The performance of blood pressure measurements, technical variation, examination programme, seasonal variation and inter-observer variation were potential bias sources and influenced blood pressure levels, but cannot be shown to be responsible for the declining trend in blood pressure and hypertension. Women became a little more physical active in leisure time and men less active. Women consumed less alcohol than men, but the amounts slightly increased by the end of the period. Body mass index >25 was seen less frequently in women than in men and this increased in men over the period. Sale of antihypertensive drugs increased in Denmark over the 1964-1991 period. There seems to be good agreement between the changes in blood pressure in the population and the decline in mortality from stroke and coronary heart disease in Denmark, which is influenced by other risk factors as well. CONCLUSION: Blood pressure distributions have shifted towards lower values in 1964-1991. Prevalence of hypertension declined up to 1983. Risk factor changes as well as treatment for hypertension contribute to this.

Apolipoprotein(a) isoforms and coronary heart disease in men: a nested case-control study.

The objective of the present study was to examine the possible associations between low molecular weight (LMW) apolipoprotein(a) (apo(a)) isoforms (F,B,S1,S2) and coronary heart disease (CHD). We conducted a nested case-control (prospective) study of five cohorts of white men: The 1936 cohort (baseline 1976, n = 548) and four cohorts from MONICA I born in 1923 (n = 463), 1933 (n = 491), 1943 (n = 504) and 1953 (n = 448) studied at baseline in 1983. At follow up in 1991, 52 subjects had developed a first myocardial infarction and 22 had been hospitalized with angina pectoris. Plasma samples obtained at baseline were stored frozen until 1993-94, when case samples (n = 74) were analyzed together with samples from matched (disease free) controls (n = 190). In a statistical model (conditional logistic regression) including all age groups, cholesterol (or apo B) level (P < 0.01), systolic blood pressure (P = 0.05) and smoking (P = 0.02) predicted CHD. In the statistical model Lp(a) interacted significantly with age (OR = 5.7; 95% CI: 1.4-23.6; P = 0.016), and high Lp(a) (over 45 mg/dl) was associated with significantly increased risk in subjects under 60 years (OR = 3.82; 95% CI: 1.47-9.96), but not in older men (OR = 0.67; 95% CI: 0.235-1.89). Therefore, we studied the impact of Lp(a)/apo(a) and other variables in subjects who had been under 60 years when they became cases. Among the younger subjects the presence of LMW apo(a) isoforms significantly predicted the development of CHD (OR = 3.83; 95% CI: 1.18-12.4). The increased risk pertained to high Lp(a) (above versus below 45 mg/dl: OR = 3.68; 95% CI: 1.03-13.10), and to Lp(a) concentrations when entered into the model as a continuous variable (P = 0.04). Cholesterol or apo B (P < 0.01), smoking (P = 0.02), systolic blood pressure (P = 0.05) and low alcohol consumption (under nine drinks/week) (P = 0.04) were also significant predictors of CHD. We conclude that LMW apo(a) isoforms are significantly associated with increased risk of CHD in men under 60 years.

[Decline in mortality from heart disease in Denmark: some methodological problems]. / Fald i dødeligheden af hjertesygdomme i Danmark: nogle metodeproblemer.

Mortality rates in Denmark from ischaemic heart diseases (IHD), other heart diseases and sudden death of unknown cause are presented for the period 1968-1992. In all age groups, mortality from IHD is higher at the beginning of the period than at the end. For other heart disease, the plot of the mortality rate is U-shaped for the age groups 65-84 and > or = 85, whereas for the age group 30-64 it first decreases and is then constant. There are an increasing number of deaths from symptomatic heart disease. For the group of unknown cause, the rates are increasing for all sex and age groups The relationship between deaths from IHD and death from unknown cause varies with period, age, sex and region. For women in Copenhagen in the age group 30-64, the mortality rate from unknown cause is higher than the rate for IHD at the end of period. Vital statistics must therefore be used cautiously in analysing trends for IHD, and even the validity of temporal changes within a country must be questioned.

[Prediction of ischemic heart disease mortality in Denmark 1982-1991 using the simulation model Prevent]. / Forudsigelse af udviklingen i dødelighed af iskaemisk hjertesygdom i Danmark 1982-1991 ved anvendelse af simulationsmodellen Prevent.

The simulation model "Prevent" estimates the effect on mortality of changes of exposures to risk factors taking the multifactorial nature of the associations between risk factors and diseases, time dimensions, and demography into account. The objective of the study is to compare the actual development of ischaemic heart disease mortality in Danmark from 1982 to 1991 with the estimated mortality based on the development of four risk factors. The sources of data used in the study are national population data and mortality rates and prevalences of risk factors from population surveys (Glostrup Population Studies). Relative risk estimates are those implemented in the Dutch version of Prevent based on international literature. The risk factors are: tobacco smoking, hypertension, cholesterol, and alcohol consumption. Results are given for ages below 65 years. The pronounced decline in mortality of ischaemic heart disease in Denmark cannot be foreseen by the model based on the development of the associated risk factors. However, the combined trend of risk factors for the last 10 to 15 years is only modest and does not indicate the dramatic decline in mortality. Prevent is too simple to make a satisfactory forecast of mortality, which however, is not the main purpose of the model. By comparing the development of a reference and an intervention population the effects of unknown factors are to some extent eliminated and the model may therefore give a good impression of the benefits of preventive interventions.

[Cognitive symptoms in persons with snoring and sleep apnea. An epidemiologic study of 1.504 women and men aged 30-60 years. The Dan-MONICA II study]. / Kognitive symptomer hos personer med snorken og søvnapnø. En epidemiologisk undersøgelse af 1.504 kvinder og moend i alderen 30-60 år. Dan-MONICA II-undersøgelsen.

The objective of the study was to evaluate the relation between every-night (habitual) snoring, sleep apnoea and cognitive complaints (concentration and memory complaints) in an adult population-based sample. In the DAN-MONICA (MONItoring trends in CArdiovascular iseases) 1504 males and females aged 30, 40, 50 and 60 years were classified according to their snoring habits. Nocturnal respiration was measured in 748 participants. The following measures were regarded as potential confounders: age, gender, unintended sleepiness, insomnia, depression, hypnotic use, alcohol consumption by questionnaire, body mass index (BMI) and blood pressure. Concentration and memory problems were both related to depression, insomnia and unintended sleepiness. Snoring and sleep apnoea (defined as a respiratory distress index-RDI > or = 5) were associated with concentration problems and unintended sleepiness. The odds ratios (95% confidence intervals) between snoring, concentration and memory problems, calculated by logistic regression analysis after adjustments for the above confounders, were 1.90 (1.23-2.91, p < 0.01) and 1.38 (0.97-1.99, NS). For those with sleep apnoea, the odds ratios were 3.53 (1.42-8.73. p < 0.001) and 1.51 (0.81-2.14, NS) for concentration and memory problems, respectively. The main conclusion drawn from this study is that cognitive complaints show a high correlation to mood, insomnia and hypersomnia. Habitual snoring and sleep apnoea show a correlation to concentration problems, but not to memory problems. This suggests that part of the association between snoring, sleep apnoea and cognitive dysfunction is related to the presence of sleep disturbances and daytime sleepiness.

Decline in mortality from heart disease in Denmark: some methodological problems.

Mortality rates in Denmark from ischemic heart diseases (IHD), other heart diseases and unknown causes are presented for the period 1968-92. In all age groups, mortality from IHD is higher at the beginning of the period than at the end. For other heart disease, the plot of the mortality rate is U-shaped for the age groups 65-84 and > or = 85, but first decreases and is then constant for the age group 30-64. There are an increasing number of deaths from symptomatic heart disease. For the group of unknown causes, the rates are increasing for all sex and age groups. The relationship between deaths from IHD and deaths from unknown causes varies with period, age, sex and region. For women in Copenhagen in the age group 30-64, the mortality rate from unknown cause is higher than the rate for IHD at the end of period. Vital statistics must therefore be used cautiously in analysing trends for IHD, and even the validity of temporal changes within a country must be questioned.

Casual blood pressure in a general Danish population. Relation to age, sex, weight, height, diabetes, serum lipids and consumption of coffee, tobacco and alcohol.

A population survey was conducted on 3608 randomly selected Danes aged 30, 40, 50 and 60 years respectively. Of these, 3400 were not in medical treatment for arterial hypertension. The following parameters were investigated: sex, age, serum lipid levels (total cholesterol, HDL cholesterol, triglycerides), presence of diabetes mellitus, height, body mass index (BMI), and average daily consumption of coffee, tobacco and alcohol. Analysis with multiple linear regression showed that all variables with the exception of triglycerides, HDL cholesterol and height were significantly associated with systolic blood pressure. Likewise all factors except diabetes, triglycerides and height were significantly associated with diastolic blood pressure. Further analysis in which the effect of each parameter was corrected for by the effects of the remaining variables, demonstrated that apart from age and sex only BMI and high alcohol consumption were positively associated with differences in blood pressure greater than a few mmHg. However, the variation in both systolic and diastolic blood pressures was only partly accounted for by the parameters studied--in the covariates analysis R2 for systolic blood pressure was 0.28 and R2 for diastolic blood pressure was 0.30. In conclusion, this investigation demonstrated that blood pressure is relatively independent of other factors important in the development of cardiovascular disease. Of the above-mentioned factors with some influence on blood pressure only age, BMI and high alcohol consumption have potential clinical importance.

Self-assessed cognitive function in snorers and sleep apneics. An epidemiological study of 1,504 females and males aged 30-60 years: the Dan-MONICA II Study.

The objective of the study was to evaluate the relation between every-night (habitual) snoring, sleep apnea and cognitive complaints (concentration and memory problems) in an adult population-based sample. In the Dan-MONICA (MONItoring trends in CArdiovascular diseases) 1,504 males and females aged 30, 40, 50 and 60 years were classified according to their snoring habits. Nocturnal respiration was measured in 748 participants. The following measures were regarded as potential confounders: age, gender, unintended sleepiness, insomnia, depression, hypnotic use, alcohol and tobacco consumption by questionnaire, body mass index (BMI) and blood pressure. Concentration and memory problems were both related to depression, insomnia and unintended sleepiness. Snoring and sleep apnea (defined as a respiratory distress index - RDI > or = 5), were associated with concentration problems and unintended sleepiness. The odds ratios (95% confidence intervals) between snoring, concentration and memory problems, calculated by logistic regression analysis after adjustments of the above confounders, were 1.90 (1.23-2.91, p < 0.01) and 1.38 (0.97-1.99, NS). For those with sleep apnea, the odds ratios were 3.53 (1.42-8.73, p < 0.001) and 1.51 (0.81-2.14, NS) for concentration and memory problems, respectively. The main conclusion drawn from this study is that cognitive complaints show a high correlation to mood, insomnia, and hypersomnia. Habitual snoring and sleep apnea show a correlation to concentration problems, but not to memory complaints. This suggests that part of the association between snoring, sleep apnea and cognitive dysfunction is related to the presence of sleep disturbances and daytime sleepiness.

Snoring, sleep apnoea and cardiovascular risk factors: the MONICA II Study.

The objective of this study was to evaluate the cardiovascular risk profile in self-reported snorers and sleep apnoeics in an adult representatively-selected population. A total of 1504 males and females, aged 30, 40, 50 and 60 years were included. The following were measured: snoring, alcohol and tobacco consumption by questionnaire, blood pressure, serum high density lipoprotein (HDL) and total cholesterol. Nocturnal respiration was determined in 748 participants. Respiratory distress index (RDI) was defined as the number of apnoea and hypopnoea lasting longer than 10 seconds per hour sleep. Habitual snoring was reported by 19.1% (9.2-24.2%, aged 30-60 years) of males and 7.9% (3.8-11.7%, age 30-60 years) of females. An RDI > or = 5 was found in 10.9% (7.1-18.3%, age 30-60 years) of males and in 6.3% (5.3-7.6%, age 30-60 years) of females. The following factors were associated with snoring: age (P < 0.02), sex (P < 0.001), body mass index (BMI) (P < 0.0001), alcohol (P < 0.05) and tobacco (P < 0.01) consumption. An RDI > or = 5 was associated with sex (P < 0.001), age (P < 0.05), BMI (P < 0.0001), tobacco (P < 0.02) and alcohol (P < 0.05) consumption. Self-reported snores showed higher systolic (P < 0.001) and diastolic (P < 0.001) blood pressure and total cholesterol (P < 0.001) and a lower HDL (P < 0.001). The participants with RDI > or = 5 showed higher systolic and diastolic blood pressure (P < 0.001) and total cholesterol (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

[Work load and cardiovascular risk factors. A cross-sectional study of employed Danish men and women]. / Arbejdsbelastning og kardiovaskulaere risikofaktorer. En tvaersnitsundersøgelse af beskaeftigede danske maend og kvinder.

As part of World Health Organisation initiated MONICA project, 2000 men and women aged 30, 40, 50 and 60 from the general population were invited to undergo a medical examination with special emphasis on cardiovascular disease. A total of 1504 (75%) participated, 1209 of whom were employed. The participants answered a questionnaire on working, social, and health conditions and underwent clinical examinations that included the measurement of blood pressure and serum cholesterol triglycerides, high density lipoprotein, fibrinogen and glycosylated haemoglobin (HbA1C) concentrations. Using the demand control model for measuring job strain suggested by Karasek, the employed people were classified according to those who had suffered job strain and those who had not in two different ways. The subjective classification was based on the participants' statements regarding demand and control in their jobs, whereas the objective classification was based on job title and mode of payment. More women than men were classified as having high strain jobs. After adjusting for age and sex no significant association was found between coronary risk factors and subjective job strain. A tendency for an association between fibrinogen and job strain was found. Body mass index and HbA1C concentration were significantly associated with objective job strain independent of confounders.

Epidemiology of snoring and obstructive sleep apnoea in a Danish population, age 30-60.

Several epidemiological studies have estimated the prevalence of obstructive sleep apnoea syndrome (OSAS). As many of those suffering from sleep apnoea may be asymptomatic, the occurrence of sleep apnoea may be underestimated. The epidemiology of self-reported snoring, sleep apnoea and OSAS, and their relationships with various symptoms, were evaluated in 1504 randomly selected males and females, aged 30, 40, 50 and 60 years. Nocturnal respiration was determined in 748 participants using inductive plethysmography. Habitual snoring was reported by 19.1% (9.2-24.2%, age 30-60 years) of the males and 7.9% (3.8-11.7%, age 30-60 years) of the females. Respiratory Distress Index (RDI) was calculated as the number of apnoeas and hypopnoeas per hour lasting longer than 10 s. RDI >/= 5 per hour was found in 10.9% (7.1-18.3%, age 30-60 years) of the males and in 6.3% (5.3-7.6%, age 30-60 years) of the females. Hypersomnia increased with the severity of sleep apnoea (P < 0.005) and was reported by 15.9% of those with RDI >/= 5. The prevalence of OSAS (hypersomnia and RDI >/= 5) was 0.9% in the females, 1.9% in the males, and in total 1.4% of all aged 30-60 years. The sensitivity was 70.8% and the specificity was 47.7% for self-reported snoring predicting RDI >/= 5. The following factors were associated with RDI >/= 5: age (P < 0.05), gender (P < 0.0001), BMI (P < 0.0001), tobacco (P < 0.02) and alcohol (P < 0.05) consumption. Snoring correlated with age (P < 0.02), gender (P < 0.001), BMI (P < 0.0001) and alcohol consumption (P < 0.05). We conclude that sleep apnoea is common and many of those with sleep apnoea are asymptomatic. Self-reported hypersomnia and snoring are not sensitive enough alone to identify those with sleep apnoea. Sufficient control of the questionnaire is thus essential in studies on snoring and the risk of cardiovascular diseases.

Job strain and cardiovascular risk factors: a cross sectional study of employed Danish men and women.

As part of the World Health Organisation initiated MONICA project, 2000 men and women aged 30, 40, 50, and 60 from the general population were invited to undergo a medical examination with special emphasis on cardiovascular disease. A total of 1504 (75%) participated, 1209 of whom were employed. The participants answered a questionnaire on working, social, and health conditions and underwent clinical examinations that included the measurement of blood pressure and serum cholesterol, triglyceride, high density lipoprotein, fibrinogen, and glycated haemoglobin (HbA1C) concentrations. Using the demand-control model for measuring job strain suggested by Karasek, the employed people were classified according to those who had suffered job strain and those who had not in two different ways. The subjective classification was based on the participants' statements regarding demand and control in their jobs whereas the objective classification was based on job title and mode of payment. More women than men were classified as having high strain jobs. After adjusting for age and sex no significant association was found between coronary risk factors and subjective job strain. A tendency for an association between fibrinogen and job strain was found. Body mass index and HbA1C concentration were significantly associated with objective job strain independent of confounders.

[Danish exercise habits in the 1980's. Attitude and behavior in relation to prevention of cardiovascular disease]. / Danske motionsvaner i 1980'erne. Holdning og adfaerd i relation til forebyggelse af hjerte-kar-sygdomme.

The results concerning exercise habits from four Danish health investigations among school pupils in the sixth and eight forms in the Municipality of Frederiksberg, adults aged 20-65 years in the County of Vejle and in Glostrup and the surrounding district and persons aged 70-75 years in the County of Roskilde, respectively, are compared. 70-80% of the Danish population take part in sports in their leisure time. Men of all ages take part in more strenuous exercise than women. The physically most active are those who have the best education and who live in their own houses. In the course of the nineteen eighties, the population has become more aware of the significance of exercise for cardiovascular disease. Similarly, during the same period, the proportion who take part in exercise has apparently increased by approximately 15%. The attitude that exercise is of significance for cardiovascular disease was connected with personal participation in sport. The knowledge that too little exercise constituted a risk factor for cardiovascular disease was increasingly realised although the connection was not definite. The social differences in exercise habits may be an explanation of the corresponding differences which have been observed in several western countries during the past decades in the mortality from cardiovascular disease.

Secular trends in serum cholesterol, high density lipoproteins and triglycerides 1964-1987.

Total mortality from cardiovascular disease in Denmark has decreased over the last 20 years for women and the last ten years for men. The possible role of simultaneous changes in serum total cholesterol has been investigated. Secular trends in serum cholesterol, high density lipoprotein cholesterol, and triglycerides, 1964-1987, are presented on the basis of four studies of 30-, 40-, 50- and 60-year-old men and women, some 8737 subjects in all. A significant decrease of 1% per year in total serum cholesterol (p less than 0.05) in both sexes and in all age groups up to 1982 was detected followed by a subsequent stabilization, 1982-1987. The decrease is not a result of methodological bias. The impact of storage at -20 degrees C for 13-24 months compared to immediate analysis of sera was studied as well as differences in analysis methods over time. The fall in population cholesterol levels might be associated with changes in polyunsaturated/saturated fat (P/S) ratio rather than total fat content of the diet, but other lifestyle changes have taken place as well.