Obesity is associated with coronary artery stenosis independently of metabolic risk factors: The population-based SCAPIS study.

BACKGROUND AND AIMS: Previous studies reported divergent results on whether metabolically healthy obesity is associated with increased coronary artery calcium and carotid plaques. We investigated this in a cross-sectional fashion in a large, well-defined, middle-aged population using coronary CT angiography (CCTA) and carotid ultrasound. METHODS: In the SCAPIS study (50-65 years, 51% female), CCTA and carotid artery ultrasound were performed in 23,674 individuals without clinical atherosclerotic disease. These subjects were divided into six groups according to BMI (normal weight, overweight, obese) and the presence of metabolic syndrome (MetS) according to the NCEP consensus criteria. RESULTS: The severity of coronary artery stenosis was increased in individuals with obesity without MetS compared to normal-weight individuals without MetS (OR 1.47, 95%CI 1.34-1.62; p < 0.0001), even after adjusting for non-HDL-cholesterol and several lifestyle factors. Such difference was not observed for the presence of carotid artery plaques (OR 0.94, 95%CI 0.87-1.02; p = 0.11). Obese or overweight individuals without any MetS criteria (except the waist criterion) showed significantly more pronounced stenosis in the coronary arteries as compared to the normal-weight individuals, while one criterion was needed to show increased plaque prevalence in the carotid arteries. High blood pressure was the most important single criterion for increased atherosclerosis in this respect. CONCLUSIONS: Individuals with obesity without MetS showed increased severity of coronary artery stenosis, but no increased occurrence of carotid artery plaques compared to normal-weight individuals without MetS, further emphasizing that obesity is not a benign condition even in the absence of MetS.

Does Physical Activity Modify the Association between Air Pollution and Recurrence of Cardiovascular Disease?

We aimed to assess a possible interaction effect between physical activity and particulate air pollution exposure on recurrence of ischemic heart disease (IHD) and stroke. We followed 2221 adult participants comprising first time IHD (1403) and stroke (818) cases from the Västerbotten Intervention Program between 1 January 1990 to 31 December 2013. During mean follow-up times of 5.5 years, 428 and 156 participants developed IHD and stroke recurrence, respectively. PM2.5 concentrations above the median (5.48 µg/m3) were associated with increased risk of IHD and stroke recurrence by 13% (95% CI -17-45%) and 21% (95% CI -19-80%), respectively. These risk increases were however only observed among those that exercised at most once a week at 21% (95% CI -5-50%) and 25% (95% CI -19-90%) for IHD and stroke recurrence, respectively. Higher frequency of exercise at recruitment was positively associated with IHD and stroke recurrence but only the association with IHD recurrence among participants with low residential PM2.5 was statistically significant (96% increased risk (95%-CI 22-215%)). However, no interaction effect between physical activity and PM2.5 exposure was found. Our findings suggest that physical activity may reduce the air pollution exposure associated risk for recurrent cardiovascular disease, likely by reducing the inflammatory response.

Air pollution, physical activity and ischaemic heart disease: a prospective cohort study of interaction effects.

OBJECTIVE: To assess a possible interaction effect between physical activity and air pollution on first incidence of ischaemic heart disease (IHD). DESIGN: Prospective cohort study. SETTING: Umeå, Northern Sweden. PARTICIPANTS: We studied 34 748 adult participants of Västerbotten Intervention Programme cohort from 1990 to January 2014. Annual particulate matter concentrations (PM2.5 and PM10) at the participants' residential addresses were modelled and a questionnaire on frequency of exercise and active commuting was completed at baseline. Cox proportional hazards modelling was used to estimate (1) association with physical activity at different levels of air pollution and (2) the association with particulate matter at different levels of physical activity. OUTCOME: First incidence of IHD. RESULTS: Over a mean follow-up of 12.4 years, there were 1148 IHD cases. Overall, we observed an increased risk of IHD among individuals with higher concentrations of particles at their home address. Exercise at least twice a week was associated with a lower risk of IHD among participants with high residential PM2.5 (hazard ratio (HR) 0.60; 95% CI: 0.44 to 0.82) and PM10 (HR 0.55; 95% CI: 0.4 to 0.76). The same beneficial effect was not observed with low residential PM2.5 (HR 0.94; 95% CI: 0.72 to 1.22) and PM10 (HR 0.99; 95% CI: 0.76 to 1.29). An increased risk associated with higher long-term exposure to particles was only observed among participants that exercised in training clothes at most one a week and among those not performing any active commuting. However, only the interaction effect on HRs for exercise was statistically significant. CONCLUSION: Exercise was associated with a lower risk of first incidence of IHD among individuals with higher residential particle concentrations. An air pollution-associated risk was only observed among those who exercised less. The findings support the promotion of physical activity and a mitigation of air pollution.

Written Examinations in Swedish Medical Schools: Minds Molded to Medicate?

Lifestyle medicine (LM) is part of official educational goals in Swedish medical schools. We studied questions concerning 5 noncommunicable diseases: diabetes, hypertension, coronary heart disease (CHD), chronic obstructive pulmonary disease (COPD), and stroke from 124 written examinations conducted between 2012 and 2015. LM knowledge yielded between 2% and 10%, whereas pharmacology-related knowledge yielded between 24% and 50%, of total points. The multiples at which pharmacology-related knowledge was valued higher than LM knowledge were 2.4 for COPD (P < .056), 4.3 for diabetes (P < .0001), 4.8 for hypertension (P < .0001), 5.2 for CHD (P < .0001), and 31.5 for stroke (P < .0001). Our results indicate that lifestyle-related knowledge, though covered by official teaching goals, is currently underrated in Swedish medical education.

Kunskap om levnadsvanor värderas olika på läkarutbildningarna - En genomgång av 124 skriftliga examinationer.

Substantial differences in valuation of lifestyle-related knowledge at Swedish medical schools Lifestyle factors are crucial for prevention and management of many non-communicable diseases such as hypertension, stroke, diabetes, coronary heart disease and chronic obstructive pulmonary disease. Lifestyle medicine is included in national learning outcomes for undergraduate medical education in Sweden. Since assessment drives learning, we reviewed questions from 124 written examinations from all 7 medical schools in Sweden, conducted between 2012 and 2015. There is up to a 5-fold difference between different universities in the weight attached to lifestyle-related knowledge compared to knowledge related to pharmacological treatments.

Cardiopulmonary fitness is a function of lean mass, not total body weight: The DR's EXTRA study.

BACKGROUND: Division by total body weight is the usual way to standardise peak oxygen uptake (peak VO2) for body size. However, this method systematically underestimates cardiopulmonary fitness in obese individuals. Our aim was to analyse whether lean-mass is a better base for a body mass-independent standard of cardiopulmonary fitness. METHODS: A population based sample of 578 men (body mass index (BMI) 19-47 kg/m(2)) and 592 women (BMI 16-49 kg/m(2)) 57-78 years of age. Peak VO2 was assessed by respiratory gas analysis during a maximal exercise test on a cycle ergometer. We studied the validity of the weight-ratio and the lean mass-ratio standards in a linear regression model. RESULTS: The weight-ratio standard implies an increase of peak VO2 per additional kg body weight with 20.7 ml/min (95% confidence interval (CI): 20.3-21.1) in women and 26.9 ml/min (95% CI: 26.4-27.5) in men. The observed increase per kg is only 8.5 ml/min (95% CI: 6.5-10.5) in men and 10.4 ml/min (95% CI: 7.5-13.4) in women. For the lean mass-ratio standard expected and observed increases in peak VO2 per kg lean mass were 32.3 (95% CI: 31.8-32.9) and 34.6 (95% CI: 30.0-39.1) ml/min for women and 36.2 (95% CI: 35.6-36.8) and 37.3 (95% CI: 32.1-42.4) ml/min in men. The lean mass-ratio standard is a body mass-independent measure of cardiopulmonary fitness in 100% of women and 58% of men; corresponding values for the weight-ratio standard were 11% and 16%. CONCLUSIONS: For comparisons of cardiopulmonary fitness across different categories of body mass, the lean mass-ratio standard should be used.

Diet, insulin secretion and insulin sensitivity--the Dose-Responses to Exercise Training (DR's EXTRA) Study (ISRCTN45977199).

Intakes of saturated fat (SF) and dietary fibre, body mass and physical activity are all associated with the incidence of type 2 diabetes mellitus. Their relative importance for the maintenance of normal glucose metabolism is not fully known. In a population-based sample of 1114 individuals, aged 58-78 years, dietary intakes were assessed by 4 d food records and cardiorespiratory fitness as maximal oxygen uptake. Insulin secretion, insulin sensitivity, the early-phase disposition index (DI30) and the total disposition index (DI120) were assessed based on an oral glucose tolerance test. Linear associations were modelled using linear regression. Combined effects were studied by introducing SF and fibre intakes, as well as cardiorespiratory fitness and waist circumference (WC) as dichotomised variables in general linear models. Intakes of dietary fibre and whole-grain bread were positively associated with insulin sensitivity, independent of physical fitness and WC. In women, dietary fibre intake was also positively associated with DI30. The negative association of high WC with DI30 was attenuated by a combination of low SF intake and high cardiorespiratory fitness. In conclusion, dietary fibre and a combination of low SF intake and high cardiorespiratory fitness may contribute to the maintenance of normal glucose metabolism, independent of WC.

BMI and an anthropometry-based estimate of fat mass percentage are both valid discriminators of cardiometabolic risk: a comparison with DXA and bioimpedance.

OBJECTIVE: To determine whether categories of obesity based on BMI and an anthropometry-based estimate of fat mass percentage (FM% equation) have similar discriminative ability for markers of cardiometabolic risk as measurements of FM% by dual-energy X-ray absorptiometry (DXA) or bioimpedance analysis (BIA). DESIGN AND METHODS: A study of 40-79-year-old male (n = 205) and female (n = 388) Finns. Weight, height, blood pressure, triacylglycerols, HDL cholesterol, and fasting blood glucose were measured. Body composition was assessed by DXA and BIA and a FM%-equation. RESULTS: For grade 1 hypertension, dyslipidaemia, and impaired fasting glucose >6.1 mmol/L, the categories of obesity as defined by BMI and the FM% equation had 1.9% to 3.7% (P < 0.01) higher discriminative power compared to DXA. For grade 2 hypertension the FM% equation discriminated 1.2% (P = 0.05) lower than DXA and 2.8% (P < 0.01) lower than BIA. Receiver operation characteristics confirmed BIA as best predictor of grade 2 hypertension and the FM% equation as best predictor of grade 1 hypertension. All other differences in area under curve were small (≤0.04) and 95% confidence intervals included 0. CONCLUSIONS: Both BMI and FM% equations may predict cardiometabolic risk with similar discriminative ability as FM% measured by DXA or BIA.

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.

Fatty acid profile of the erythrocyte membrane preceding development of Type 2 diabetes mellitus.

BACKGROUND AND AIMS: The respective roles of dietary fatty acids in the pathogenesis of diabetes are as yet unclear. Erythrocyte membrane fatty acid (EMFA) composition may provide an estimate of dietary fatty acid intake. This study investigates the relation between EMFA composition and development of Type 2 diabetes mellitus. METHODS AND RESULTS: In a nested case-referent design we studied 159 individuals tested as non-diabetic at baseline who after a mean observation time of 5.4+/-2.6years were diagnosed with Type 2 diabetes mellitus and 291 sex- and age-matched referents. Higher proportions of pentadecanoic acid (15:0) and heptadecanoic acid (17:0) were associated with a lower risk of diabetes. In accordance with earlier findings, higher proportions of palmitoleic (16:1 n-7), dihomo-gamma-linolenic (20:3 n-6) and adrenic (22:4 n-6) acids were associated with increased risk, whereas linoleic (18:2 n-6) and clupanodonic (22:5 n-3) acids were inversely associated with diabetes. After adjustment for BMI, HbA1c, alcohol intake, smoking and physical activity the only significant predictors were 15:0 and 17:0 as protective factors and 22:4 n6 as risk factor. CONCLUSION: In accordance with previous studies, our results indicate that EMFA-patterns predict development of Type 2 diabetes mellitus. The inverse association with two saturated fatty acids, previously shown to reflect consumption of dairy products, is a new finding.

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 250,000. 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.