Diabetes and obesity in Northern Sweden: occurrence and risk factors for stroke and myocardial infarction

Undiagnosed type 2 diabetes is common - intensified screening of established risk groups is imperative in Sweden: the SDPP cohort

BACKGROUND

Undiagnosed type 2 diabetes (T2D) is a global problem. Current strategies for diagnosis in Sweden include screening individuals within primary healthcare who are of high risk, such as those with hypertension, obesity, prediabetes, family history of diabetes, or those who smoke daily. In this study, we aimed to estimate the proportion of individuals with undiagnosed T2D in Stockholm County and factors associated with T2D being diagnosed by healthcare. This information could improve strategies for detection.

METHODS

We used data from the Stockholm Diabetes Prevention Programme (SDPP) cohort together with information from national and regional registers. Individuals without T2D aged 35-56 years at baseline were followed up after two ten-year periods. The proportion of diagnosed T2D was based on register information for 7664 individuals during period 1 and for 5148 during period 2. Undiagnosed T2D was assessed by oral glucose tolerance tests at the end of each period. With logistic regression, we analysed factors associated with being diagnosed among individuals with T2D.

RESULTS

At the end of the first period, the proportion of individuals with T2D who had been diagnosed with T2D or not was similar (54.0% undiagnosed). At the end of the second period, the proportion of individuals with T2D was generally higher, but they were less likely to be undiagnosed (43.5%). The likelihood of being diagnosed was in adjusted analyses associated with overweight (OR=1.85; 95% CI 1.22-2.80), obesity (OR=2.73; 95% CI 1.76-4.23), higher fasting blood glucose (OR=2.11; 95% CI 1.67-2.66), and self-estimated poor general health (OR=2.42; 95% CI 1.07-5.45). Socioeconomic factors were not associated with being diagnosed among individuals with T2D. Most individuals (>71%) who developed T2D belonged to risk groups defined by having at least two of the prominent risk factors obesity, hypertension, daily smoking, prediabetes, or family history of T2D, including individuals with T2D who had not been diagnosed by healthcare.

CONCLUSIONS

Nearly half of individuals who develop T2D during 10 years in Stockholm County are undiagnosed, emphasizing a need for intensified screening of T2D within primary healthcare. Screening can be targeted to individuals who have at least two prominent risk factors.

Risk of Stroke and Cardiovascular Disease According to Diabetes Mellitus Status

The purpose of this study was to investigate the importance of prevention and management of diabetes by analyzing stroke and cardiovascular disease (CVD) incidence among people with diabetes. This secondary analysis of the Korea National Health and Nutrition Examination Survey Ⅶ (2016-2018) data included 15,039 adults. Diabetes status was significantly associated with sex, age, marital status, household size, education level, employment status, household income, hypertension, dyslipidemia, stroke, CVD, osteoarthritis, osteoporosis, kidney failure, depression, level of stress, smoking, drinking, body mass index, weight control, and the number of days of walking per week; however, it was not associated with rheumatoid arthritis. Stroke and CVD risk significantly increased in the presence of diabetes (by 4.123 times and 3.223 times, respectively). The incidences of stroke and CVD were significantly higher among participants with diabetes than among those without diabetes. Thus, preventing and systematically managing diabetes is crucial to reducing related complications and mortality.

Incidence and Risk Factors for Stroke Among 14 European Countries

Background This study compared the risk factors for and incidence of stroke among 14 European countries by using the Survey of Health, Aging, and Retirement in Europe (SHARE). Methods The analysis was based on data collected during 2006 to 2007 from Wave 2 of SHARE and panel data from respondents interviewed during 2004 to 2005. Results and Conclusion The highest stroke incidence rates were found in Denmark, Poland, and Sweden; these incidence rates were more than double that of Spain. Stroke was mostly associated with elderly people (age, ≥65 years) in Sweden, France, Switzerland, the Czech Republic, and Greece. In addition, stroke incidence was high among young males (age, <65 years) in Italy and elderly males in Germany and Switzerland. A negative association was found between stroke and vigorous exercise for younger people in Sweden and elderly people in Poland, whereas moderate exercise was significantly associated with stroke only for elderly Belgians, Greeks, and Irish.

Vitamin A and systemic inflammation as protective factors in multiple sclerosis

Background:

Vitamin A is important for the immune system, and might suppress inflammatory activity in multiple sclerosis (MS).

Objectives:

We aimed to examine if vitamin A levels were associated with MS risk in samples collected prospectively and during gestation.

Methods:

We measured Retinol Binding Protein (RBP – a surrogate marker for vitamin A) and high-sensitivity C-reactive protein (hs-CRP) levels, in (1) prospectively collected biobank blood samples from MS cases and controls, and (2) gestational samples where the offspring had later developed MS, and gestational control samples. The risk of MS was calculated using matched multivariable logistic regression adjusted for confounders.

Results:

In prospective samples, RBP levels within the second quintile (vs. the first) were associated with a lower MS risk (OR = 0.38, 95% CI 0.19–0.74). No effect on MS risk in the offspring by gestational RBP levels was found. In young subjects hs-CRP levels ≥10 mg/l in prospective samples were associated with a lower MS risk (OR = 0.36, 95% CI 0.14–0.95).

Conclusions:

Our results suggest that sub-optimal vitamin A levels may be associated with MS risk. The association between hs-CRP levels and MS risk in young subjects may support the role of the hygiene hypothesis in MS aetiology.

Perceived stress and incidence of Type 2 diabetes: a 35-year follow-up study of middle-aged Swedish men

AIM

To explore incident cases of diagnosed diabetes over 35 years of follow-up in relation to self-perceived stress at baseline.

METHODS

This was a population-based random sample of 7251 men derived from the Primary Prevention Trial Study, aged 47-56 years at baseline and without prior history of diabetes, coronary heart disease and stroke. Incident diabetes was identified from hospital discharge and death registries as principal or secondary diagnosis. Cox proportional hazards regression was used to evaluate the potential association between stress and diabetes.

RESULTS

During a 35-year follow-up, a total of 899 men were identified with diabetes. The crude incidence was 5.2 per 1000 persons-years. At baseline, 15.5% men reported permanent stress related to conditions at work or home. After adjusting for age and competing risk of death, the estimated 35-year conditional probability of diabetes in men with permanent stress was 42.6%, compared with 31.0% for those with periodic stress and 31.2% with no stress. In age-adjusted Cox regression analysis, men with permanent stress had a higher risk of diabetes [hazard ratio 1.52 (95% CI 1.26-1.82)] compared with men with no (referent) or periodic stress [hazard ratio 1.09 (95% CI 0.94-1.27)]. The association between stress and diabetes was slightly attenuated but remained significant after adjustment for age, socio-economic status, physical inactivity, BMI, systolic blood pressure and use of anti-hypertensive medication [hazard ratio 1.45 (95% CI 1.20-1.75)]. When examining principal diagnosis of diabetes cases separately from secondary diagnoses cases, the excess risk of diabetes associated with permanent stress remained significant both in age (only) and multivariable adjusted models.

CONCLUSION

Self-perceived permanent stress is an important long-term predictor of diagnosed diabetes, independently of socio-economic status, BMI and other conventional Type 2 diabetes risk factors.

International differences in the links between obesity and physiological dysregulation: the United States, England, and Taiwan

Excess weight has generally been associated with adverse health outcomes; however, the link between overweight and health outcomes may vary with socioeconomic, cultural, and epidemiological conditions. We examine associations of weight with indicators of biological risk in three nationally representative populations: the US National Health and Nutrition Examination Survey, the English Longitudinal Study of Ageing, and the Social Environment and Biomarkers of Aging Study in Taiwan. Indicators of biological risk were compared for obese (defined using body mass index (BMI) and waist circumference) and normal weight individuals aged 54+. Generally, obesity in England was associated with elevated risk for more markers examined; obese Americans also had elevated risks except that they did not have elevated blood pressure (BP). Including waist circumference in our consideration of BMI indicated different links between obesity and waist size across countries; we found higher physiological dysregulation among those with high waist but normal BMI compared to those with normal waist and normal BMI. Americans had the highest levels of biological risk in all weight/waist groups. Cross-country variation in biological risk associated with obesity may reflect differences in health behaviors, lifestyle, medication use, and culture.

Patients with diabetes are not more likely to have atypical symptoms when seeking care of a first myocardial infarction. An analysis of 4028 patients in the Northern Sweden MONICA Study

AIM

To describe symptoms of a first myocardial infarction in men and women with and without diabetes.

METHODS

We conducted a population-based study of 4028 people aged 25-74 years, with first myocardial infarction registered in the Northern Sweden Multinational MONItoring of trends and determinants in CArdiovascular disease (MONICA) myocardial infarction registry between 2000 and 2006. Symptoms were classified as typical or atypical according to the World Health Organization MONICA manual.

RESULTS

Among patients with diabetes, 90.1% reported typical symptoms of myocardial infarction; the corresponding proportion among patients without diabetes was 91.5%. In the diabetes group, 88.8% of women and 90.8% of men had typical symptoms of myocardial infarction. No differences were found in symptoms of myocardial infarction between women with and without diabetes or between men with and without diabetes. Atypical symptoms were more prevalent in the older age groups (> 65 years) than in the younger age groups (< 65 years). The increases were approximately equal among men and women, with and without diabetes. Diabetes was not an independent predictor for having atypical symptoms of myocardial infarction.

CONCLUSIONS

Typical symptoms of myocardial infarction were equally prevalent in patients with and without diabetes and there were no sex differences in symptoms among persons with diabetes. Diabetes was not a predictor of atypical symptoms.

The obesity epidemic slows among the middle-aged population in Sweden while the socioeconomic gap widens

Background

Obesity prevalence has continuously increased in Northern Sweden as elsewhere. A cohort effect has been shown and an increasing proportion of the middle-aged population is maintaining body weight.

Objective

To test the hypothesis that the obesity epidemic continues but at different speeds that are dependent on socioeconomic status.

Design

Cross-sectional (103,940 adults) and longitudinal (26,872 adults) data from the Västerbotten Intervention Program 1990–2007 were included. All adults in Västerbotten County are invited to a health examination at the ages of 40, 50, and 60 years. Body mass index (BMI) and socioeconomic status, assessed by residence location, marital status, and education were evaluated.

Results

BMI increased in all groups but was greater among men. During 1990–1995 and 2002–2007, mean BMIs were 25.9 and 26.8 among men and 25.2 and 25.9 among women. The trend of increasing BMI slowed around the year 2000 (p<0.001), but this was only observed among the highly educated adults in the most urbanized area. The difference between educational groups increased throughout the study period (men p=0.014, women p=0.002). Longitudinal data for both sexes showed a twofold higher baseline prevalence of obesity among individuals with basic compared to high education and it nearly doubled in all groups during the 10-year follow-up. Low education, living in a rural environment, and living alone were independent predictors of obesity development. The overall cumulative 10-year incidence was 9.4% in men, 9.1% in women, and twofold higher among those with basic and mid-level education who live in rural areas compared to those with high education who live in cities.

Conclusion

The trend of increasing obesity has slowed in this middle-aged Northern Sweden population, but this trend shift occurred primarily among those with high education who live in an urban environment. Greater efforts to combat obesogenic environments are needed and should take socioeconomic and sociocultural aspects into account.

The effect of early life factors on 28 day case fatality after acute myocardial infarction

Aims: To study the association of size at birth and social circumstances at birth with 28 day case fatality of acute myocardial infarction (AMI). Methods: Based on 1,776 first cases of AMI occurring in Uppsala Birth Cohort (men and women born 1915—1929) between 1964 and 2002. Data on circumstances at birth retrieved from archived obstetric records; data on social characteristics in adulthood, hospitalizations, and date of death obtained through linkage to Censuses, Hospital Discharge Register, and Cause of Death Register. Results: We found a U-shaped association between standardized birth weight and case fatality of AMI in men (p = 0.045 for age and period adjusted quadratic trend over quintiles of standardized birth weight) that was driven by cases of AMI occurring during the early years of follow-up. We found no association between standardized birth weight and case fatality of AMI in women. There was a statistically non-significant inverse association of AMI case fatality with social class at birth as well as with social class and household income in adulthood in the cohort. Marital status was a strong determinant of case fatality in men. Conclusions: Standardized birth weight for gestational age was associated with case fatality of AMI in men. Social class at birth was weakly inversely associated with case fatality of AMI in the cohort.

Population-wide changes in reported lifestyle are associated with redistribution of adipose tissue

AIMS

The Northern Sweden MONICA project 1986-2004 demonstrated a marked increase in average body mass, an unchanged prevalence of diabetes, and a decrease in myocardial infarctions and lately also in stroke. This study estimates the relative importance of time-trends in lifestyle on average waist and hip circumference on a population level.

METHODS

From a series of independent cross-sectional surveys, a study population of 2,831 men and 2,976 women was formed. Associations between lifestyle factors and waist and hip circumference were estimated. Partial regression coefficients for every level of the lifestyle factors were multiplied by the differences in the proportion of the population reporting the corresponding levels of the respective lifestyle factors in 1986 and 2004. The sum of the product terms for each item represents the respective estimated impact of change in waist and hip circumference.

RESULTS

Lifestyle trends associated with changes in hip circumference were (women/men): higher education level (+4.0 mm/+2.4 mm), fewer smokers (+0.4 mm/+0.9 mm), a slight increase in alcohol consumption (+0.4 mm/+0.3 mm), and more saturated fat from meat in women (-0.9 mm) and more fibre from grains in men (+0.6 mm). Average waist circumference was influenced by increased levels of physical activity (-2.2 mm/-4.6 mm), fewer female smokers (-0.3 mm), and a higher intake of saturated fatty acids from meat among men (+1.8 mm).

CONCLUSIONS

We identified physical activity and the intake of meat and whole-grain products as prime candidates for lifestyle interventions in northern Sweden.

Validity and utilization of epidemiological data: a study of ischaemic heart disease and coronary risk factors in a local population

OBJECTIVES

To calculate the burden of ischaemic heart disease (IHD) and coronary risk factors in a defined population using data from all public providers of health care, i.e. inpatient and outpatient care in all settings.

STUDY DESIGN

Cross-sectional, 1-year retrospective study.

METHODS

The main outcome measures were the number of individuals by diagnosis and by care setting, and gender- and age-specific event rates by diagnosis.

RESULTS

Less than half of the individuals who visited any care provider for IHD or coronary risk factors were identified in the hospital discharge register. Calculation of the actual burden of disease in the population showed that when hospital discharge data were combined with outpatient data, there were no or slight differences in the age-specific rates of acute myocardial infarction (AMI), while the rates of angina were between two-fold and four-fold higher, and unspecified IHD was between three-fold and ten-fold higher in individuals aged > or =50 years compared with using hospital discharge data alone. The rates of hypertension, diabetes and lipid disorders increased in all age groups when outpatient data were added to hospital discharge data. The differences in the rates were more pronounced in women aged 50-79 years. However, the age-specific rates were higher in men except for hypertension which was higher in older women.

CONCLUSION

Data for epidemiological analyses of diseases are often based on hospital discharge data. This study found that hospital discharge data provide limited information on patients treated for IHD and coronary risk factors, except for AMI. These findings suggest that hospital discharge data should be combined with outpatient care data to provide a more comprehensive estimate of the burden of IHD and its risk factors.

Prevalence and incidence of Type 2 diabetes and its complications 1996-2003--estimates from a Swedish population-based study

AIMS

To determine the prevalence and incidence of Type 2 diabetes and its complications in Uppsala county, Sweden between 1996 and 2003.

METHODS

Retrospective population-based study of patients with Type 2 diabetes identified in computerized medical records at 26 county primary care centres. Prevalence and incidence of Type 2 diabetes were estimated in the population aged 30-39, 40-49, 50-59, 60-69, 70-79 and > or = 80 years. Mortality, prevalence and incidence of complications in patients with Type 2 diabetes were determined through linkage to national inpatient, uraemia and cause-of-death registers.

RESULTS

Crude prevalence of Type 2 diabetes increased from 2.2 to 3.5% between 1996 and 2003. In the population aged > or = 30 years, the age- and sex-adjusted period increase was 53%[odds ratio (OR) 1.53, 95% confidence interval (CI) 1.47-1.58]. Crude population incidence was approximately stable after 1997 (3.7 cases/1000 residents in 1997 compared with 3.8/1000 in 2003). Age- and sex-adjusted mortality rates in Type 2 diabetic patients decreased by 4% per year (OR 0.96, 95% CI 0.94-0.97). Prevalence rates of cardiovascular disease in Type 2 diabetic patients were essentially stable, affecting 13.8% of females and 18.0% of males in 2003. No trend was detected for prevalence of renal failure or incidence of acute myocardial infarction, stroke and amputation.

CONCLUSIONS

Prevalence of Type 2 diabetes increased in Uppsala county between 1996 and 2003 as a consequence of approximately stable incidence since 1997 and declining mortality. Rates of diabetes-related complications, notably cardiovascular disease, continued to impose a substantial burden.

Psychological distress and risk of pre-diabetes and Type 2 diabetes in a prospective study of Swedish middle-aged men and women

AIMS

To determine the role of psychological distress as a predictor of pre-diabetes and Type 2 diabetes.

METHODS

This cohort study comprised 2127 Swedish middle-aged men and 3100 women with baseline normal glucose tolerance measured by oral glucose tolerance test. At follow-up 8-10 years later, 245 men and 177 women had pre-diabetes [impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and IFG + IGT] and Type 2 diabetes was detected in 103 men and 57 women. Baseline psychological distress was measured by an index of five questions concerning anxiety, apathy, depression, fatigue and insomnia. Odds ratios (ORs) were estimated for pre-diabetes and Type 2 diabetes in association with total psychological distress. In addition, ORs of the single-item questions were calculated.

RESULTS

In men, adjusted ORs (95% confidence interval) in the highest index group of psychological distress compared with the lowest group were 1.9 (1.2-2.8) and 2.2 (1.2-4.1) for pre-diabetes and Type 2 diabetes, respectively. Corresponding estimates in women were 1.2 (0.7-2.1) and 0.5 (0.2-1.2). In the middle symptoms groups, adjusted ORs in men were 1.1 (0.8-1.4) for pre-diabetes and 1.2 (0.7-2.0) for Type 2 diabetes and in women 1.8 (1.1-3.0) and 0.7 (0.3-1.4). When analysed separately, the associations with each of the five single factors were similar.

CONCLUSIONS

The results indicate that psychological distress, including symptoms of anxiety, apathy, depression, fatigue and insomnia, increases the risk of pre-diabetes and Type 2 diabetes in Swedish middle-aged men. Increased risks were not present in women, except for pre-diabetes in the middle index group.

Obesity prevalence from a European perspective: a systematic review

Background

Obesity has been recognised as an important contributing factor in the development of various diseases, but comparative data on this condition are limited. We therefore aimed to identify and discuss current epidemiological data on the prevalence of obesity in European countries.

Methods

We identified relevant published studies by means of a MEDLINE search (1990–2008) supplemented by information obtained from regulatory agencies. We only included surveys that used direct measures of weight and height and were representative of each country's overall population.

Results

In Europe, the prevalence of obesity (body mass index ≥ 30 kg/m²) in men ranged from 4.0% to 28.3% and in women from 6.2% to 36.5%. We observed considerable geographic variation, with prevalence rates in Central, Eastern, and Southern Europe being higher than those in Western and Northern Europe.

Conclusion

In Europe, obesity has reached epidemic proportions. The data presented in our review emphasise the need for effective therapeutic and preventive strategies.

[Coronary disease risk attributable to cardiovascular risk factors in the Spanish population]

INTRODUCTION AND OBJECTIVES

The proportion of the ischemic heart disease (IHD) burden attributable to cardiovascular risk factors in Spain has traditionally been extrapolated from populations in other countries. The aim of this study was to estimate the IHD risk attributable to smoking, hypercholesterolemia, hypertension, diabetes and excess weight using data from studies carried out in the Spanish population.

METHODS

Data on the prevalence of cardiovascular risk factors in the general population were obtained from a meta-analysis of 48 cross-sectional studies carried out in Spain, and data on corresponding prevalences among IHD patients were derived from the PRIAMHO II and PREVESE II multicenter hospital registries. Crude and adjusted relative risks of IHD were obtained from follow-up data collected over 5 years in a primary-care cohort of 6124 adults without cardiovascular disease. The crude and adjusted population attributable fractions for various risk factors were calculated for both sexes combined and for men and women separately.

RESULTS

Among men, 42.5% (95% confidence interval [CI] 6.8%-59.6%) of the adjusted incidence of IHD was attributable to overweight, 33.9% (95% CI 22.6%-41.0%) to smoking, 19.4% (95% CI 8.2%-26.5%) to hypercholesterolemia, and 15.5% (95% CI 1.6%-24.6%) to hypertension. Among women, 36.5% (95% CI -8.0%-56.3%) of IHD cases were attributable to overweight, 24.8% (95% CI 12.0%-31.9%) to diabetes, and 20.1% (95% CI 6.1%-28.6%) to hypercholesterolemia.

CONCLUSIONS

The cardiovascular risk factors found to contribute most to IHD in the Spanish population were excess weight in both sexes, followed by smoking in men.

Age and gender differences in the impact of diabetes on the prevalence of ischemic heart disease: a population-based register study

OBJECTIVE

To explore age and gender differences in the impact of diabetes on the prevalence of ischemic heart disease (IHD) in a defined population.

METHODS

Data were obtained from an administrative health care register covering a population of about 415,000. The study included all patients aged 45-74 years diagnosed between 1999 and 2003 with IHD (n=11,311) and diabetes (n=10,364) by physicians at all primary health care centres (PHCs) and out- and inpatient clinics at all hospitals in the county of Ostergötland, Sweden.

RESULTS

In the 45-54-year-old age group, diabetes was associated with an increase in IHD prevalence equivalent to ageing about 20 years in women and 10 years in men. The diabetes/nondiabetes IHD prevalence rate ratio (IPR) decreased with age in both men and women (trend p-values <0.001). The IPR was higher among women than men in each age group, though the female relative excess decreased from 75% higher in the 45-54-year-old age group to 33% higher in the 65-74-year-old age group (trend p-value=0.018).

CONCLUSIONS

The relative gender difference in the impact of diabetes on IHD in younger middle-aged patients remained up to the age of 65 years, decreasing considerably thereafter.

The importance of free fatty acids in the development of Type 2 diabetes

The recent increase in the prevalence of obesity has been associated with a coincident rise in the prevalence of Type 2 diabetes, whereas weight loss has been shown to decrease the risk of Type 2 diabetes. The pathophysiological mechanisms that have been proposed to explain this link are fundamentally concerned with insulin resistance and the decline in pancreatic B-cell function that accompanies an increase in visceral obesity. They involve the rise in the plasma concentrations of free fatty acids (FFAs) that are associated with an increase in fat mass. Elevated levels of FFAs can lead to insulin resistance, and evidence is growing that B-cell function is impaired through lipotoxicity. Factors such as tumour necrosis factor-alpha (TNF-alpha) and adiponectin, released from adipose tissue, can also modulate insulin resistance. Many interventions that are helpful in treating or preventing Type 2 diabetes, such as weight loss and certain pharmacological interventions, reduce circulating FFA concentrations to a greater or lesser extent. Recent study results suggest that peroxisome proliferator-activated receptor (PPAR)gamma agonists have an effect on the development of Type 2 diabetes. However, in light of concerns over the apparent increase in congestive heart failure with PPARgamma agonists, their place in the prevention of Type 2 diabetes remains to be determined.

Stroke prevention in the high-risk patient

Strokes are increasing in number due to an ageing population and are largely preventable. In the highest risk patients, a 90% relative risk reduction for stroke is attainable by appropriately using all the measures proven to reduce stroke: smoking cessation, a Mediterranean diet, control of hypertension, anticoagulants or antiplatelet agents, lipid lowering drugs and appropriate carotid endarterectomy. Vitamin therapy to lower homocysteine and carotid stenting are additional measures that may yet prove beneficial. Diet, smoking cessation and appropriate carotid endarterectomy reduce stroke by more than do pharmacotherapies. Blood pressure control depends more on selecting appropriate therapy individualised for the patient, than on using any particular drug class. This review, therefore, places pharmacotherapy in perspective as part of, but not all of, stroke prevention.

Trends in food intakes in Swedish adults 1986–1999: findings from the Northern Sweden MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) Study

Objective

To determine changes in reported food frequency in adults between 1986 and 1999.

Design

Four consecutive cross-sectional surveys.

Setting

Counties of Norrbotten and Västerbotten, Northern Sweden.

Subjects

The Northern Sweden MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) population, four independent cross-sectional surveys in 1986, 1990, 1994 and 1999. Randomly selected age-stratified samples of the population aged 25–64 years. Analysis is based on 2982 males and 3087 females who completed an 84-item food-frequency questionnaire.

Results

Between 1986 and 1999, average reported consumption of 3%-fat milk decreased from 42 to 7 intakes month-1 in men and from 28 to 4 intakes month-1 in women. Reported use of 1.5%-fat milk increased from 6 to 27 intakes month-1 in men and from 6 to 24 in women. Monthly intakes of potatoes and root vegetables decreased from 38 to 27 in men and from 39 to 32 in women. Consumption of pasta increased from 4 to 7 intakes month-1 in both sexes. Intakes of solid fats with 80% fat content dropped from 92 to 62 per month in men and from 78 to 52 per month in women, whereas use of 40%-fat spread increased from 12 to 22 intakes month-1 in men and from 5 to 26 in women. Monthly intakes of vegetable oil increased from 3 to 12 in men and from 3 to 15 in women. The percentage of overweight or obese individuals (body mass index >25 kg m-2) increased from 52 to 65% in men and from 41 to 52% in women (P for linear trend in all these changes, <0.001).

Conclusions

Our data indicate reduced consumption of foods with a high content of saturated fats. In spite of that, there is an unbroken trend towards increased obesity.

Reported food intake and distribution of body fat: a repeated cross-sectional study

Background

Body mass, as well as distribution of body fat, are predictors of both diabetes and cardiovascular disease. In Northern Sweden, despite a marked increase in average body mass, prevalence of diabetes was stagnant and myocardial infarctions decreased. A more favourable distribution of body fat is a possible contributing factor.

This study investigates the relative importance of individual food items for time trends in waist circumference (WC) and hip circumference (HC) on a population level.

Methods

Independent cross-sectional surveys conducted in 1986, 1990, 1994 and 1999 in the two northernmost counties of Sweden with a common population of 250000. Randomly selected age stratified samples, altogether 2982 men and 3087 women aged 25–64 years. Questionnaires were completed and anthropometric measurements taken. For each food item, associations between frequency of consumption and waist and hip circumferences were estimated. Partial regression coefficients for every level of reported intake were multiplied with differences in proportion of the population reporting the corresponding levels of intake in 1986 and 1999. The sum of these product terms for every food item was the respective estimated impact on mean circumference.

Results

Time trends in reported food consumption associated with the more favourable gynoid distribution of adipose tissue were increased use of vegetable oil, pasta and 1.5% fat milk. Trends associated with abdominal obesity were increased consumption of beer in men and higher intake of hamburgers and French fried potatoes in women.

Conclusion

Food trends as markers of time trends in body fat distribution have been identified. The method is a complement to conventional approaches to establish associations between food intake and disease risk on a population level.

Impact of follow-up time and re-measurement of the electrocardiogram and conventional cardiovascular risk factors on their predictive value for myocardial infarction

OBJECTIVE

To explore if the predictive power of mid-life electrocardiogram (ECG) abnormalities and conventional cardiovascular risk factors for future myocardial infarction, change over a 30-year follow-up period and if repeated examination improves their predictive power.

DESIGN AND SETTING

Longitudinal population-based study.

PARTICIPANTS

A total of 2322 men aged 50 years, with a total follow-up period of 30 years and 1221 subjects were re-examined at age of 70 years.

MAIN OUTCOME MEASURE

Risk for fatal and nonfatal myocardial infarction (n = 470) analysed at age 50 and 70 years, and separately for 1-10, 11-20 and 21-30 years after first examination. Investigations included a 12-lead ECG, blood pressure, body mass index, smoking habits, and glucose and lipid variables.

RESULTS

Whilst high blood pressure and dyslipidaemia variables, such as apolipoprotein B/apolipoprotein A1 ratio, measured at age 50 showed an almost unchanged predictive power during the three decades of follow up, ECG abnormalities, insulin and BMI were only significant predictors during the two first decades of follow up. Despite increased prevalences of ECG abnormalities and obesity with age, they predicted for future myocardial infarction in midlife only whilst fasting insulin and smoking regained their predictive power when re-measured at age 70.

CONCLUSION

Whilst hypertension and dyslipidaemia were consistent as risk factors, length of follow-up period and age at baseline investigations affected the predictive power of ECG abnormalities, fasting insulin, BMI and smoking. In the elderly, ECG abnormalities did not contribute to the prediction of myocardial infarction but smoking and fasting insulin may be important in the pathophysiology leading to MI especially in this age group.

Favourable trends in the incidence and outcome of myocardial infarction in nondiabetic, but not in diabetic, subjects: findings from the MONICA myocardial infarction registry in northern Sweden in 1989-2000

BACKGROUND

The aim of this study was to compare time trends in incidence, case fatality and mortality due to myocardial infarction (MI) in patients with or without diabetes.

METHODS

This study was based on the Northern Sweden MONICA Project MI registry with a target population of about 200,000 inhabitants in the age group 35--64 years in the two northernmost counties of Sweden. During 1989--2000, 6254 patients who had had an MI according to MONICA criteria were included in this study: 4569 patients had a first MI and 1685 had a recurrent MI. Sixteen per cent of the men and 20% of the women had had diabetes mellitus diagnosed prior the MI.

RESULTS

Over the 12-year period, there was a declining trend in incidence and case fatality in first MI. Also, the event rates (first ever and recurrent MI) declined in men without diabetes. In women without diabetes favourable time trends were seen in first ever MI, recurrent MI and in case fatality. There were no favourable time trends for any of these outcomes in patients with diabetes.

CONCLUSION

In nondiabetic subjects below the age of 65, the incidence of, and case-fatality in, MI declined. This led to a decreased mortality over the 12-year period. These favourable trends over time were not observed in diabetic subjects.

High levels of tissue plasminogen activator (tPA) antigen precede the development of type 2 diabetes in a longitudinal population study. The Northern Sweden MONICA study

Background

Impaired fibrinolysis is found in impaired glucose tolerance and type 2 diabetes, associated with components of the metabolic syndrome. There are no data concerning fibrinolysis in subjects with normal glucose tolerance that convert to diabetes.

Methods

We studied the activities of tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1) and the levels of tPA antigen (a marker of endothelial dysfunction) in 551 subjects with normal glucose tolerance in 1990 in relation to incident diabetes during nine years of follow-up.

Results

Subjects with diabetes at follow-up (n = 15) had significantly lower baseline tPA activity and higher PAI-1 activity and tPA antigen than non-converters. The risk of diabetes increased linearly across quartiles of PAI-activity (p = 0.007) and tPA antigen (p < 0.001) and decreased across quartiles of tPA activity (p = 0.026). The risk of diabetes with low tPA activity or high PAI-1 activity persisted after adjustment for age and sex but diminished to a non-significant level after further adjustments. The odds ratio of diabetes for high tPA antigen was 10.4 (95% confidence interval 2.7–40) adjusted for age and sex. After further adjustment for diastolic blood pressure, waist circumference, insulin, triglycerides, fasting and post load glucose the odds ratio was 6.5 (1.3–33, p = 0.024).

Conclusions

Impaired fibrinolysis and endothelial dysfunction are evident in subjects with normal glucose tolerance who later develop diabetes. High tPA antigen is predictive of future diabetes independent from the metabolic syndrome.

Silent myocardial infarction in women with impaired glucose tolerance: the Northern Sweden MONICA study

Background

Patients with impaired glucose tolerance (IGT) have an increased risk of cardiovascular disease (CVD) that is independent of traditional risk factors. Hence, slightly elevated glucose levels, even in the non-diabetic range, might be associated with increased macrovascular disease.

Methods

Within the Northern Sweden MONICA project a population survey was performed in 1986. Electrocardiograms (ECG's) were recorded for half of the survey (n = 790) and oral glucose test was carried out in 78 % of those. The association between subjects with ECG's indicating previously unknown myocardial infarction (ukMI), IGT and conventional risk factors were analyzed by logistic regression for men and women separately, adjusting for age, smoking, hypercholesterolemia and hypertension.

Results

Impaired glucose tolerance was significantly more common among women with ukMI, but not in men, compared to the group with normal ECG. In men, no variable was significantly associated with ukMI although the odds ratio (OR) for hypercholesterolemia was of borderline significance, 3.2 (95% confidence interval (CI) 0.9 to 11). The OR of having ukMI was 4.1 (CI 1.1 to 15) in women with IGT compared to women with normal glucose tolerance after multiple adjustment. The OR for hypertension was of borderline significance; 3.3 (CI 0.97 to 11).

Conclusion

We found that IGT was associated with ECG findings indicating silent myocardial infarction in women in a middle-aged general population in northern Sweden. The results persisted even after adjusting for known risk factors.

No increase in the prevalence of known diabetes between 1986 and 1999 in subjects 25-64 years of age in northern Sweden

AIMS

A global increase in diabetes is predicted due to higher body weight and less physical activity. Over the period 1986-1999, the body mass index (BMI) of the adult population of northern Sweden increased from 25.3 to 26.2 and the prevalence of obesity (BMI > or = 30) from 11% to 15%, although this was more distal than central adiposity. Our hypothesis was that this would lead to a higher prevalence of diabetes.

METHODS

Four population surveys with new and independent cohorts of 2000 invited subjects, 25-64 years old, in 1986, 1990, 1994 and 1999. In the first three surveys an oral glucose tolerance test was carried out in 47%.

RESULTS

Over the time period 1986-1999 there was no increase in the prevalence of known diabetes. No trends were noted in the finding of previously undiagnosed diabetes or impaired glucose tolerance over the period 1986-1994, although the confidence intervals are wide. Fasting, but not post-load, glucose levels increased with 0.040 mmol/year (95% CI 0.026; 0.055) in men and 0.033 mmol/year (0.023; 0.044) in women.

CONCLUSION

In spite of a marked increase in BMI, we found no increased prevalence of known diabetes over a 13-year observation period, although our data cannot exclude minor increases in undiagnosed diabetes. The development of more distal than abdominal obesity, a diet with less saturated fat and lower glycaemic index and fewer regular smokers in the population may contribute to this. The effects of obesity may thus be attenuated by other secular trends in society and highlight potential ways of curbing the worldwide increase in diabetes.